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Sample records for barrier wall construction

  1. Meeting the challenge of constructing a uniquely difficult barrier wall

    International Nuclear Information System (INIS)

    Stamnes, R.L.; Orlean, H.M.; Thompson, N.E.

    1997-01-01

    A soil-bentonite vertical barrier wall with intersecting and round corners was constructed in complex geology and steep terrain to enclose and dewater a 1.4 hectare (3.5 acre) area once used for hazardous waste lagoons and landfills at the Queen City Farms (QCF) Superfund site in Maple Valley, Washington. The barrier system, including cap and barrier wall, was designed to contain light non-aqueous phase liquid (LNAPL), in addition to subsurface soil and ground water contaminated with chromium, polychlorinated biphenyls, polyaromatic hydrocarbons, trichloroethylene, dichloroethylene and vinyl chloride in the dissolved-phase. These contaminants threaten a drinking water aquifer beneath the site. Constructing the vertical barrier was a challenge due to steep slopes of 20 percent along the alignment (19.2 meter elevation change in the top of the wall), a 22.5 meter (75 foot) design wall depth, heavily consolidated clays and silts, open works gravels (gravel without finer soils), and geologic discontinuity. The barrier wall is keyed into either a glacial till or thin clayey-silt aquitard. Extensive earth moving, stepped walls and many construction techniques were used to enable construction of this barrier wall. Commonly accepted constructability criteria would have discouraged the construction of this wall

  2. A new alternative in vertical barrier wall construction

    International Nuclear Information System (INIS)

    Rawl, G.F.

    1997-01-01

    A new proprietary vertical barrier wall system has been developed to revolutionize the construction process by eliminating many of the concerns of conventional installation method's with respect to performance, installation constraints and costs. Vertical barrier walls have been used in the environmental and construction industries for a variety of purposes, usually for cut-off or containment. The typical scenario involves a groundwater contamination problem, in which a vertical barrier wall is utilized to contain or confine the spread of contaminants below the ground surface. Conventional construction techniques have been adequate in many applications, but often fall short of their intended purposes due to physical constraints. In many instances, the economics of these conventional methods have limited the utilization of physical barrier walls. Polywall, the trade name for this new barrier wall technology, was subsequently developed to meet these needs and offer a number of distinct advantages in a variety of scenarios by maximizing confinement and minimizing installation costs. Polywall is constructed from chemically resistant high density polyethylene (HDPE) plastic. It has proven in a half-dozen projects to date to be the most cost-effective and technically sound approach to many containment situations. This paper will cover the development of the technology and will provide a brief synopsis of several installations

  3. Hempcrete Noise Barrier Wall for Highway Noise Insulation : Research & Construction

    OpenAIRE

    KC, Prabesh

    2016-01-01

    The purpose of this thesis was to study the possibility of Hempcrete or hemp-lime composite noise barrier walls in the highways and to construct the walls for the acoustic test according to the European Union Standards EN ISO 717-1 and ISO 10140-2 for air-borne sound insulation. The thesis was commissioned by the company Hemprefine Oy, and all the standard tests were performed in the HAMK-Ruukki Sheet Metal Centre in Hämeenlinna and the VTT Technical Research Centre of Finland Ltd in Espoo. ...

  4. Air barrier systems: Construction applications

    Energy Technology Data Exchange (ETDEWEB)

    Perrault, J.C

    1989-01-01

    An examination is presented of how ordinary building materials can be used in an innovative manner to design, detail, and construct effective air barrier systems for common types of walls. For residential construction, the air drywall approach uses the interior gypsum board as the main component of the wall air barrier system. Joints between the gypsum board and adjacent materials or assemblies are sealed by gaskets. In commercial construction, two different techniques are employed for using gypsum board as air barrier material: the accessible drywall and non-accessible drywall approaches. The former is similar to the air drywall approach except that high performance sealants are used instead of gaskets. In the latter approach, exterior drywall sheathing is the main component of the air barrier system; joints between boards are taped and joints between boards and other components are sealed using elastomeric membrane strips. For various types of commercial and institutional buildings, metal air barrier systems are widely used and include pre-engineered curtain walls or sheet metal walls. Masonry wall systems are regarded as still the most durable, fireproof, and soundproof wall type available but an effective air barrier system has typically been difficult to implement. Factory-made elastomeric membranes offer the potential to provide airtightness to masonry walls. These membranes are applied on the entire masonry wall surface and are used to make airtight connections with other building components. Two types of product are available: thermofusible and peel-and-stick membranes. 5 figs.

  5. Case history: Vertical barrier wall system for Superfund Site

    International Nuclear Information System (INIS)

    Koelling, M.A.; Kovac, C.P.; Norris, J.E.

    1997-01-01

    Design considerations and construction aspects are presented for the installation of a vertical barrier wall system for the Boeing Company at a Superfund Site near Seattle, WA. The construction was performed during 1996. The vertical barrier wall system included: (1) a soil-bentonite (SB) slurry wall, approximately 670 meters (2200 feet) in length, ranging from 12 to 21 meters (40 to 70 feet) in depth; (2) expansion of a cover system over the area enclosed by the SB wall; and (3) surface drainage improvements. Design and construction of the system addressed requirements of a Consent Decree for the site issued in 1993. The paper discusses the development of the design to meet remedial performance goals of preventing migration of contaminants in the soil/groundwater system and aiding aquifer restoration. Secondly, the paper details installation of the SB wall, highlighting the more significant construction issues, which included excavation of the wall through glacially deposited cobbles/boulders/till as well as addressing the severe elevation changes along the wall alignment. Thirdly, the paper presents Quality Assurance (QA) monitoring and testing performed during the construction phase

  6. Application of flexi-wall in noise barriers renewal

    Directory of Open Access Journals (Sweden)

    B. Daee

    2015-12-01

    Full Text Available This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF and polyurea. This wall system (flexi-wall is intended to be employed as a vertical extension to existing noise barriers (sound walls in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The results of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound wall application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound wall applications was also developed.

  7. Green noise wall construction and evaluation.

    Science.gov (United States)

    2011-09-01

    This report details the research performed under Phase I of a research study titled Green Noise Wall Construction and Evaluation that looks into the feasibility of using green noise barriers as a noise mitigation option in Ohio. This phase incl...

  8. CMHC research project: Testing of air barriers construction details: Report

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This project was conducted to quantify the air leakage characteristics of the header joist, the electric outlets, and the window openings in wood-frame walls. The study evaluated the sealed internal membrane method, where polyethylene sheet and sealant provide the air barrier; the external air barrier method, which uses a continuous vapour permeable membrane (spun-bonded olefin film), sandwiched between two layers of external wall sheathing; and the airtight drywall method, where the interior gypsum board finish, together with framing materials and gaskets, are used as the air barrier. In addition, the traditional approach to wood-frame wall construction, where no special attention is given to achieving a continuous air barrier, was evaluated for comparison.

  9. Slurry walls and slurry trenches - construction quality control

    International Nuclear Information System (INIS)

    Poletto, R.J.; Good, D.R.

    1997-01-01

    Slurry (panel) walls and slurry trenches have become conventional methods for construction of deep underground structures, interceptor trenches and hydraulic (cutoff) barriers. More recently polymers mixed with water are used to stabilize the excavation instead of bentonite slurry. Slurry walls are typically excavated in short panel segments, 2 to 7 m (7 to 23 ft) long, and backfilled with structural materials; whereas slurry trenches are fairly continuous excavations with concurrent backfilling of blended soils, or cement-bentonite mixtures. Slurry trench techniques have also been used to construct interceptor trenches. Currently no national standards exist for the design and/or construction of slurry walls/trenches. Government agencies, private consultants, contractors and trade groups have published specifications for construction of slurry walls/trenches. These specifications vary in complexity and quality of standards. Some place excessive emphasis on the preparation and control of bentonite or polymer slurry used for excavation, with insufficient emphasis placed on quality control of bottom cleaning, tremie concrete, backfill placement or requirements for the finished product. This has led to numerous quality problems, particularly with regard to identification of key depths, bottom sediments and proper backfill placement. This paper will discuss the inspection of slurry wall/trench construction process, identifying those areas which require special scrutiny. New approaches to inspection of slurry stabilized excavations are discussed

  10. CMHC research project: Testing of air barrier construction details, II: Report

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    Air leakage control through the building envelope of wood framed houses is more important than ever. The leakage of air is controlled by the air barrier system. There are several new technologies to construct an air barrier system for the building envelope. These are the Poly Approach, the Air Drywall Approach and the EASE system. The development of these systems was undertaken primarily by the building community without significant research and development. The purpose of this study was to determine the actual performance of several different types of construction details for each of the different approaches. Each of these details was designed and constructed using one of the air barrier methods and tested in the laboratory. The test details included the sill plate, the partition wall, the stair stringer, the electrical outlets, the bathtub detail, the plumbing stack detail, the metal chimney detail, the bathroom fan detail and the EASE wall system.

  11. Use of deep soil mixing as an alternate verticle barrier to slurry walls

    International Nuclear Information System (INIS)

    Miller, A.D.

    1997-01-01

    Slurry walls have become an accepted subsurface remediation technique to contain contaminated zones. However, situations develop where conventional slurry wall excavation techniques are not suitable. The use of conventional containment wall construction methods may involve removal and disposal of contaminated soils, stability concerns and the risk of open excavations. For these reasons, other installation techniques have received further consideration. Deep Soil Mixing (DSM) has emerged as a viable alternative to conventional slurry wall techniques. In situations dictating limited soil removal for contamination or stability concerns, or where space is a limitation, DSM can be used for installation of the barrier. Proper installation of a DSM wall requires sufficient monitoring and sampling to evaluate the continuity, mixing effectiveness, permeability and key into the confining layer. This paper describes a case study where DSM was used to cross major highways to avoid open excavation, and along slopes to reduce stability concerns. The DSM barrier was tied to an existing conventional slurry wall that had been installed in more stable areas without highway traffic

  12. Wall Construction; Carpentry: 901892.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    The curriculum guide outlines a course designed to provide instruction in floor and wall layout, and in the diverse methods and construction of walls. Upon completion of this course the students should have acquired a knowledge of construction plans and structural foundations in addition to a basic knowledge of mathematics. The course consists of…

  13. PRIORITISING LEAN CONSTRUCTION BARRIERS IN UGANDA'S CONSTRUCTION INDUSTRY

    Directory of Open Access Journals (Sweden)

    Henry Mwanaki Alinaitwe

    2009-06-01

    Full Text Available Engaging in lean construction efforts could prove to be highly rewarding for building firms in Uganda. However, lean construction is risky and can be disastrous if not properly managed. Lean production efforts in some other countries have not been successful due to the many barriers to its successful implementation. To enable sound lean construction efforts and to increase the chances of success in eliminating waste, a thorough investigation of the barriers is essential. This study presents 31 barriers and investigates their influence (strength on the success of lean construction initiatives. Structured interviews were carried out with technical managers of building firms to assess their perception of the barriers to lean production based on their experience at their firms. The strongest barrier is the provision of inputs exactly when required. Additionally, the barriers were ranked according to the ease of overcoming each. The easiest barrier to overcome is keeping the required items in the right place. Finally, a graphical aid is provided to enable decision makers to concentrate their efforts on the influential (strong, yet easy to overcome barriers. A lack of buildable designs and a participative management style for the workforce are the most important barriers to successful waste reduction in terms of strength and ease of overcoming. On the other hand, a lack of an organisational culture that supports teamwork, a lack of prefabrication and a lack of knowledgeable and skilled workers are regarded as low in strength, and at the same time difficult to overcome.

  14. Barriers of lean construction implementation in the Moroccan construction industry

    Science.gov (United States)

    Bajjou, Mohamed Saad; Chafi, Anas

    2018-04-01

    Improving the production system performance has become a fundamental pillar that must be taken into consideration in the construction industry. Recent developments in the construction sector have led to renewed interest in new techniques of management. Lean Construction is a very effective approach that has gained a high popularity by its ability to eliminate waste and maximize the value for the customer. Although both developed and developing countries have gained large benefits by implementing Lean Construction approach, several experiences showed many barriers that are hindering its implementation especially in developing countries. This paper aims to assess the critical barriers to the successful implementation in the Moroccan construction industry. Based on a literature review, followed by an analysis of data collected from a questionnaire survey which targeted 330 practitioners in the Moroccan construction field, several barriers were identified as key barriers. The findings of this investigation revealed that there are significant barriers such as Lack of knowledge about Lean Construction concepts, Unskilled Human Resources, and insufficient financial resources.

  15. Model Tests on the Retaining Walls Constructed from Geobags Filled with Construction Waste

    Directory of Open Access Journals (Sweden)

    Hua Wen

    2016-01-01

    Full Text Available Geobag retaining wall using construction waste is a new flexible supporting structure, and the usage of construction waste to fill geobags can facilitate the construction recycling. In this paper, model tests were performed on geobag retaining wall using construction waste. The investigation was concentrated on the slope top settlement, the distribution characteristics of the earth pressures on retaining walls and horizontal wall displacements, and slope failure modes. The results indicated that the ultimate loads that the slope tops with retaining walls could bear were 87.5%~125% higher than that of the slope top without retaining walls. The ultimate loading of strengthened slopes with different slope ratios from 1 : 0.75 to 1 : 0.25 could be reduced by 11.8% to 29.4%. The horizontal displacements of the retaining walls constructed from geobags were distributed in a drum shape, with the greatest horizontal displacements occurring about 1/3~1/2 of the wall height away from the bottom of the wall. As the slope ratio increased, the failure of the slope soil supported by geobag retaining wall using construction waste changed from sliding to sliding-toppling (dominated by sliding and then to toppling-sliding (dominated by toppling. The range of 1/3~1/2 of wall height is the weak part of the retaining walls, which should be strengthened with certain measures during the process of design and construction.

  16. Model Tests on the Retaining Walls Constructed from Geobags Filled with Construction Waste

    OpenAIRE

    Wen, Hua; Wu, Jiu-jiang; Zou, Jiao-li; Luo, Xin; Zhang, Min; Gu, Chengzhuang

    2016-01-01

    Geobag retaining wall using construction waste is a new flexible supporting structure, and the usage of construction waste to fill geobags can facilitate the construction recycling. In this paper, model tests were performed on geobag retaining wall using construction waste. The investigation was concentrated on the slope top settlement, the distribution characteristics of the earth pressures on retaining walls and horizontal wall displacements, and slope failure modes. The results indicated t...

  17. CMHC [Canada Mortgage and Housing Corporation] research project: Testing of air barrier construction details 2

    Energy Technology Data Exchange (ETDEWEB)

    1993-03-31

    Air leakage control through the building envelope of wood framed houses is more important than ever. This is because owners expect better temperature control, higher indoor humidity in winter, low energy consumption and building durability. The leakage of air is controlled by the air barrier system. There are several new technologies to construct an air barrier system for the building envelope. These are the Poly Approach, the Air Drywall Approach (ADA) and the EASE system. The development of these systems was undertaken primarily by the building community without significant research and development. While it is believed that these methods improve airtightness it is not known if the improvement is marginal or significant. A study was conducted to determine actual performace of several different types of construction details for each of the different approaches. Each of these details was designed and constructed using one of the air barrier methods and tested in the laboratory. The test details included sill plate, the partition wall, the stair stringer, the electrical outlets, the bathtub detail, the plumbing stack detail, the metal chimney detail, the bathroom fan detail and the EASE wall system. The test results revealed that the Poly, ADA and EASE approaches reduce air leakage by a factor of six, if applied with a modest degree of workmanship. Further, certain Poly details are to be reconsidered because they lack adequate support against design wind load pressures. 37 figs., 12 tabs.

  18. Wave trapping by dual porous barriers near a wall in the presence of bottom undulation

    Science.gov (United States)

    Kaligatla, R. B.; Manisha; Sahoo, T.

    2017-09-01

    Trapping of oblique surface gravity waves by dual porous barriers near a wall is studied in the presence of step type varying bottom bed that is connected on both sides by water of uniform depths. The porous barriers are assumed to be fixed at a certain distance in front of a vertical rigid wall. Using linear water wave theory and Darcy's law for flow past porous structure, the physical problem is converted into a boundary value problem. Using eigenfunction expansion in the uniform bottom bed region and modified mild-slope equation in the varying bottom bed region, the mathematical problem is handled for solution. Moreover, certain jump conditions are used to account for mass conservation at slope discontinuities in the bottom bed profile. To understand the effect of dual porous barriers in creating tranquility zone and minimum load on the sea wall, reflection coefficient, wave forces acting on the barrier and the wall, and surface wave elevation are computed and analyzed for different values of depth ratio, porous-effect parameter, incident wave angle, gap between the barriers and wall and slope length of undulated bottom. The study reveals that with moderate porosity and suitable gap between barriers and sea wall, using dual barriers an effective wave trapping system can be developed which will exert less wave force on the barriers and the rigid wall. The proposed wave trapping system is likely to be of immense help for protecting various facilities/ infrastructures in coastal environment.

  19. Wave Trapping by Dual Porous Barriers Near a Wall in the Presence of Bottom Undulation

    Institute of Scientific and Technical Information of China (English)

    R.B. Kaligatla; Manisha; T. Sahoo

    2017-01-01

    Trapping of oblique surface gravity waves by dual porous barriers near a wall is studied in the presence of step type varying bottom bed that is connected on both sides by water of uniform depths. The porous barriers are assumed to be fixed at a certain distance in front of a vertical rigid wall. Using linear water wave theory and Darcy's law for flow past porous structure, the physical problem is converted into a boundary value problem. Using eigenfunction expansion in the uniform bottom bed region and modified mild-slope equation in the varying bottom bed region, the mathematical problem is handled for solution. Moreover, certain jump conditions are used to account for mass conservation at slope discontinuities in the bottom bed profile. To understand the effect of dual porous barriers in creating tranquility zone and minimum load on the sea wall, reflection coefficient, wave forces acting on the barrier and the wall, and surface wave elevation are computed and analyzed for different values of depth ratio, porous-effect parameter, incident wave angle, gap between the barriers and wall and slope length of undulated bottom. The study reveals that with moderate porosity and suitable gap between barriers and sea wall, using dual barriers an effective wave trapping system can be developed which will exert less wave force on the barriers and the rigid wall. The proposed wave trapping system is likely to be of immense help for protecting various facilities/ infrastructures in coastal environment.

  20. INVESTIGATION OF RECYCLED TIRE CHIPS FOR USE IN GDOT CONCRETE USED TO CONSTRUCT BARRIER WALLS AND OTHER APPLIATIONS–PHASE I

    Science.gov (United States)

    2017-09-01

    In 2013, GDOT constructed more than 42,000 LF of concrete barrier utilizing a Class A concrete mixture design (3000 psi). There may be potential for the beneficial utilization of recycled tire chips in concrete barrier applications which can possibly...

  1. Design and construction of a deep slurry trench barrier

    International Nuclear Information System (INIS)

    Deming, P.W.

    1997-01-01

    A 24 m (80 ft) deep slurry trench surrounding a former chromium manufacturing facility on the Patapsco River in Baltimore, Maryland was constructed in 1995 to contain groundwater and site Soils, and to reduce the volume of groundwater extracted to maintain an inward gradient. In 1992, an embankment made of crushed stone was constructed in the Patapsco River to make land for barrier construction outboard of the bulkheads, and to protect the barrier. Stability of the slurry-supported trench excavation in the embankment required construction from an elevated work platform. An extended reach backhoe was used to excavate the deep slurry trench and to clean the trench bottom. Soil-Bentonite backfill was prepared at a central mixing area and transported by truck to the perimeter barrier. A synthetic membrane was inserted partially into the backfill for connection to a multimedia cap, and for redundancy and erosion control in the tidal zone. Hydraulic testing of the aquitard contained by the barrier demonstrated excellent performance of the barrier and bottom closure. Detailed definition of subsurface conditions and the closure stratum was necessary for the design and successful construction of the barrier, and is recommended for comparable slurry trench construction projects

  2. A Structurally Specialized Uniform Wall Layer is Essential for Constructing Wall Ingrowth Papillae in Transfer Cells

    Science.gov (United States)

    Xia, Xue; Zhang, Hui-Ming; Offler, Christina E.; Patrick, John W.

    2017-01-01

    Transfer cells are characterized by wall labyrinths with either a flange or reticulate architecture. A literature survey established that reticulate wall ingrowth papillae ubiquitously arise from a modified component of their wall labyrinth, termed the uniform wall layer; a structure absent from flange transfer cells. This finding sparked an investigation of the deposition characteristics and role of the uniform wall layer using a Vicia faba cotyledon culture system. On transfer of cotyledons to culture, their adaxial epidermal cells spontaneously trans-differentiate to a reticulate architecture comparable to their abaxial epidermal transfer cell counterparts formed in planta. Uniform wall layer construction commenced once adaxial epidermal cell expansion had ceased to overlay the original outer periclinal wall on its inner surface. In contrast to the dense ring-like lattice of cellulose microfibrils in the original primary wall, the uniform wall layer was characterized by a sparsely dispersed array of linear cellulose microfibrils. A re-modeled cortical microtubule array exerted no influence on uniform wall layer formation or on its cellulose microfibril organization. Surprisingly, formation of the uniform wall layer was not dependent upon depositing a cellulose scaffold. In contrast, uniform wall cellulose microfibrils were essential precursors for constructing wall ingrowth papillae. On converging to form wall ingrowth papillae, the cellulose microfibril diameters increased 3-fold. This event correlated with up-regulated differential, and transfer-cell specific, expression of VfCesA3B while transcript levels of other cellulose biosynthetic-related genes linked with primary wall construction were substantially down-regulated. PMID:29259611

  3. Fire barrier evaluation of the wall between spent nuclear fuel storage basins and reactor areas, 105KE and 105KW

    International Nuclear Information System (INIS)

    Johnson, B.H.

    1994-01-01

    This evaluation is intended to provide a comprehensive assessment of the risks from fire and fire related perils for the fire barriers between spent nuclear fuel storage basins and reactor areas, 105KE and 105KW. As a result of this fire barrier evaluation the present walls and the components thereof are not a true listed fire rated assembly. However, due to the construction of these barriers and the components thereof, these barriers will provide an equivalent level of protection provided the recommendations in Section 8.0 of this report are completed. These recommended upgrades are based upon sound engineering practice by a Registered Fire Protection Engineer. The construction of the barrier are substantial enough to provide the required 2-hr fire resistance rating. The primary concern is the numerous penetrations in the barrier. There are many penetrations that are adequate and no additional work is required. These penetrations are the ones that were poured-in-place at the time of construction. The penetrations that are of concern are some of the doors, the HVAC ducts, and the unsealed piping and conduit penetrations. There are several metal doors that should be replaced because the existing doors have either a non-approved window or louver that will not limit the spread of fire to one side of the barrier. All unsealed piping and conduit penetrations should be firestopped with an approved firestopping material. The existing non-active ducts that pass through the barrier should be disconnected at the barrier and the opening sealed with an approved firestopping method

  4. Using Frozen Barriers for Containment of Contaminants

    Science.gov (United States)

    2017-09-21

    barriers are constructed of grout slurry and plastic or steel sheet pilings. Circumferential barriers can be used to completely enclose a source of...2.1.1 Slurry walls A soil-bentonite slurry trench cutoff wall (slurry wall) is excavated and backfilled with grout, cement , or soil-bentonite...installation requires a mixing area, and there is a substantial amount of excavation and the need to dispose of spoil. The advantages of cement -based

  5. Air barrier details: How effective are they

    Energy Technology Data Exchange (ETDEWEB)

    A project was initiated to measure the air leakage through three typical details in wood frame walls: the header joist, electric outlets, and window openings. Three construction methods were tested: the poly approach, where a sealed internal polyethylene sheet and caulking provide the air barrier; an external air barrier approach using a continuous vapor permeable membrane sandwiched between two layers of external wall sheathing; and the airtight drywall approach (ADA), where the interior gypsum board finish along with framing and gaskets are the air barrier. Twelve sample panels using each of the three details were built using each of the construction approaches. A traditional wood-frame wall construction detail, with no effort made to create a continuous air barrier, was also built and tested for comparison. The samples were put in a test chamber so that air pressures could create infiltration or exfiltration through the panel under loads similar to those due to wind action. Measurements were made at several stages during construction of each sample to see the effect of different components on the air leakage. Overall, all but the traditional samples and the ADA electrical outlet panel exceeded the current tightness standards for glass and aluminum curtain walls. All three approaches could meet the airtightness standards of the R-2000 program. The total air leakage calculated for each approach is under 20% of that in traditional construction. Of the details tested, window detailing offers the greatest potential for increasing overall airtightness compared to traditional methods. 1 ref., 2 figs., 1 tab.

  6. The Significance of Barriers to Entry in the Construction Industry

    Directory of Open Access Journals (Sweden)

    Gerard de Valence

    2012-11-01

    Full Text Available This research looks at the significance of barriers that firms considering entry into the construction industry might face. Drawing on the microeconomic characteristics of imperfectly competitive and oligopolistic markets the analysis finds that there are a dozen barriers to entry that affect the industry, but their significance depends on the product type. The discussion covers the question of product homogeneity in construction and evidence for the existence of barriers to entry in concentration levels. Barriers to entry specific to construction are then identified, which leads to an analysis of how they operate and their significance (high, medium or low in different market types, thus increasing our understanding of construction industry dynamics.

  7. Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 2: 2x4 Walls

    Energy Technology Data Exchange (ETDEWEB)

    Kochkin, V. [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, J. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2017-06-01

    Part 2 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides straightforward and cost-effective strategies to construct durable, energy-efficient walls. It addresses walls constructed with 2x4 wood frame studs, wood structural panel (WSP) sheathing as wall bracing and added backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1.5 inches thick over the WSP, and a cladding system installed over the foam sheathing in low-rise residential buildings up to three stories high. Walls with 2x6 framing are addressed in Part 1 of the Guide.

  8. Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 2: 2x4 Walls

    Energy Technology Data Exchange (ETDEWEB)

    Kochkin, V. [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, J. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2017-08-31

    Part 2 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides straightforward and cost-effective strategies to construct durable, energy-efficient walls. It addresses walls constructed with 2x4 wood frame studs, wood structural panel (WSP) sheathing as wall bracing and added backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1.5 inches thick over the WSP, and a cladding system installed over the foam sheathing in low-rise residential buildings up to three stories high. Walls with 2x6 framing are addressed in Part 1 of the Guide.

  9. CMHC [Canadian Mortgage and Housing Corporation] research project: Testing of air barriers construction details

    Energy Technology Data Exchange (ETDEWEB)

    1991-08-26

    The airtightness of building envelopes is important in controlling comfort and energy usage in houses. Leakage generally occurs through construction details, where there are joints or connections between materials, or where there are penetrations for services or other components. A study was conducted to quantify the air leakage characteristics of three such details in wood-frame walls: the header joist, the electric outlets, and the window opening detail. Three construction methods employed to achieve airtightness were evaluated: the sealed internal membrane approach (POLY); the external air barrier approach using a continuous vapour permeable membrane sandwiched between two layers of wall sheathing(EASE); and the airtight drywall approach (ADA). Test panels containing the details were subjected to air leakage testing at pressure differentials from 50 to 1,000 pascals. Measurements of air flow were made and evidence of failure of the barrier due to pressure loading was noted. Leakage rates for the header detail with the POLY, EASE and ADA panels were 24%, 18% and 10% respectively of that for the reference panel. For the electrical outlet joint, leakage rates for POLY and EASE panels were 24% and 36%, while the ADA panel had higher leakage rates than the traditional panel. For the window detail, leakage rates were lowest for the ADA panel and similar for the POLY and EASE panels; all were less than 15% that of traditional panels. 48 figs., 2 tabs.

  10. Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 1: 2x6 Walls

    Energy Technology Data Exchange (ETDEWEB)

    Kochkin, V. [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, J. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2017-08-31

    Part 1 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides time-proven, practical, and cost-effective strategies for constructing durable, energy-efficient walls. It addresses walls constructed with 2x6 wood frame studs, wood structural panel (WSP) exterior sheathing, and a cladding system installed over WSP sheathing in low-rise residential buildings up to three stories high.

  11. Opportunities and barriers to straw construction

    DEFF Research Database (Denmark)

    White, Caroline Meyer; Howard, Thomas J.; Lenau, Torben Anker

    2012-01-01

    produced to support communication between clients and the consultants and facilitate the straw build design and decision making process. The intended audiences for the design guide are clients of small scale construction projects, architects, engineers, builders of straw construction, homeowner...... construction, and a series of qualitative interviews with a variety of stakeholders from previous straw build housing projects, results were gathered to find the most influential motives, barriers and considerations for straw build housing construction. Based on this empirical data, a design guide has been...

  12. Design for tsunami barrier wall based on numerical analyses of tsunami inundation at Shimane Nuclear Power Plant

    International Nuclear Information System (INIS)

    Kiyoshige, Naoya; Yoshitsugu, Shinich; Kawahara, Kazufumi; Ookubo, Yoshimi; Nishihata, Takeshi; Ino, Hitoshi; Kotoura, Tsuyoshi

    2014-01-01

    The conventional tsunami assessment of the active fault beneath the Japan sea in front of the Shimane nuclear power plant and the earthquake feared to happen at the eastern margin of the Japan sea does not expect a huge tsunami as to be assumed on the Pacific sea coast. Hence, the huge tsunami observed at the power plant located near the source of the Tohoku Pacific sea earthquake tsunami whose run-up height reached TP+15m is regarded as the level 2 tsunami for the Shimane nuclear power plant and planned to construct the tsunami barrier walls to endure the supposed level 2 tsunami. In this study, the setting of the Level 2 tsunami by using the numerical analysis based on the non-linear shallow water theory and evaluation for the design tsunami wave pressure exerted on the counter measures by using CADMAS-SURF/3D are discussed. The designed tsunami barrier walls which are suitable to the power plant feasibility and decided from the design tsunami wave pressure distribution based on Tanimoto's formulae and standard earthquake ground motion Ss are also addressed. (author)

  13. Soil-bentonite design mix for slurry cutoff walls used as containment barriers

    International Nuclear Information System (INIS)

    Rad, N.S.; Bachus, R.C.; Jacobson, B.D.

    1995-01-01

    In recent years, soil-bentonite slurry cutoff walls have been increasingly used as containment barriers around contaminated soils to impede or, in some cases, nearly eliminate the off-site migration of contaminated ground water or other potentially hazardous liquids. The paper presents the procedures used and the results obtained during an extensive laboratory testing program performed to select varying soil-bentonite slurry mix components for a soil-bentonite slurry cutoff wall constructed around an old landfill at a former oil refinery. The landfill is underlain to varying depths by a coarse granular soils that has been exposed to oil-products. Compatibility of three commercially available bentonite products with the free oil-products and the oil-contaminated ground water found at some locations in the landfill was initially investigated. Based on the test results, one of the bentonite products was selected for use in the soil-bentonite slurry testing program. A clayey soil from a borrow source, potable water from the site, and subsurface soils from the proposed soil-bentonite slurry wall alignment were used to form different soil-bentonite slurry mixes. Slump tests were performed to evaluate the workability of the mixes. Based on the test results, a single mix was selected for further study, including permeability/compatibility testing. The results of the compatibility testing program are presented and discussed in the paper. A specific design mix methodology for evaluating the chemical compatibility of soil-bentonite slurry mixes with permeants is proposed

  14. Moisture Conditions in Passive House Wall Constructions

    OpenAIRE

    Gullbrekken, Lars; Geving, Stig; Time, Berit; Andresen, Inger

    2015-01-01

    Buildings for the future, i.e zero emission buildings and passive houses, will need well insulated building envelopes, which includes increased insulation thicknesses for roof, wall and floor constructions. Increased insulation thicknesses may cause an increase in moisture levels and thereby increased risk of mold growth. There is need for increased knowledge about moisture levels in wood constructions of well insulated houses, to ensure robust and moisture safe solutions. Monitoring of w...

  15. Sustainable wall construction and exterior insulation retrofit technology process and structure

    Science.gov (United States)

    Vohra, Arun

    2000-01-01

    A low-cost process for exterior wall insulation retrofit, or new wall construction by stacking layers of fabric tube filled with insulating material against a wall and covering them with mesh and stucco provides a durable structure with good insulating value.

  16. Characterizing material properties of cement-stabilized rammed earth to construct sustainable insulated walls

    Directory of Open Access Journals (Sweden)

    Rishi Gupta

    2014-01-01

    Full Text Available Use of local materials can reduce the hauling of construction materials over long distances, thus reducing the greenhouse gas emissions associated with transporting such materials. Use of locally available soils (earth for construction of walls has been used in many parts of the world. Owing to the thermal mass of these walls and the potential to have insulation embedded in the wall section has brought this construction material/technology at the forefront in recent years. However, the mechanical properties of the rammed earth and the parameters required for design of steel reinforced walls are not fully understood. In this paper, the author presents a case study where full-scale walls were constructed using rammed earth to understand the effect of two different types of shear detailing on the structural performance of the walls. The mechanical properties of the material essential for design such as compressive strength of the material including effect of coring on the strength, pull out strength of different rebar diameters, flexural performance and out-of-plane bending on walls was studied. These results are presented in this case study.

  17. Engineered surface barriers for waste disposal sites: lysimeter facility design and construction

    International Nuclear Information System (INIS)

    Phillips, S.J.; Ruben, M.S.; Kirkham, R.R.

    1988-01-01

    A facility to evaluate performance of engineered surface carriers for confinement of buried wastes has been designed, constructed, and operations initiated. The Field Lysimeter Test Facility is located at the US Department of Energy's Hanford Site in Richland, Washington. The facility consists of 18 one-dimensional drainage and weighing lysimeters used to evaluate 7 replicated barrier treatments. Distinct layers of natural earth materials were used to construct layered soil and rock barriers in each lysimeter. These barrier designs are capable in principal of significantly reducing or precluding infiltration of meteoric water through barriers into underlying contaminated zones. This paper summarizes salient facility design and construction features used in testing of the Hanford Site's engineered surface barriers

  18. Experimental study on joint construction method for aseismatic walls of reactor buildings, (1)

    International Nuclear Information System (INIS)

    Sugita, Kazunao; Mogami, Tatsuo; Ezaki, Tetsuro

    1987-01-01

    On the aseismatic walls of a reactor auxiliary building, many temporary openings are provided at the time of the construction for carrying equipment in later, due to the demand of shortening the construction period. Thus on the aseismatic walls, in most cases there are the joints due to the concrete placed later. As equipment tends to be unitized and become large, the quipment is placed close to the wall having an opening, consequently, the workability is poor, and the standardization of construction method is urgently demanded. The conventional method of closing temporary openings has the problems of safety and connecting reinforcing bars, therefore, the new construction method was proposed. In reactor buildings, the joints of walls are unavoidable, and since those are large scale structures, the joints are numerous. Therefore, at the joint parts, it abandoned and buried frames are used, it is advantageous in the time and cost of joint construction. In both cases, the mechanical properties were confirmed by the fundamental performance test partially modeling the joints and the verifying test modeling the whole walls. In this paper, the test of applying only shearing force to joint models is reported. (Kako, I.)

  19. State of offsite construction in India-Drivers and barriers

    Science.gov (United States)

    Arif, M.; Bendi, D.; Sawhney, A.; Iyer, K. C.

    2012-05-01

    The rapid growth of the construction industry in India has influenced key players in the industry to adopt alternative technologies addressing time, cost and quality. The rising demand in housing, infrastructure and other facilities have further highlighted the need for the construction industry to look at adopting alternate building technologies. Offsite construction has evolved as a panacea to dealing with the under-supply and poor quality in the current age construction industry. Several offsite techniques have been adopted by the construction sector. Although, different forms of offsite techniques have been around for a while but their uptake has been low in the Indian context. This paper presents the perceptions about offsite construction in India and highlights some of the barriers and drivers facing the Indian construction industry. The data was gathered through a survey of 17 high level managers from some of the largest stakeholder organizations of the construction sector in India. The influence of time and cost has been highlighted as a major factor fuelling the adoption of offsite construction. However, the influence of current planning systems and the need for a paradigm shift are some of the prominent barriers towards the adoption of offsite techniques.

  20. Development of a high-quality cut-off wall using electrophoresis

    International Nuclear Information System (INIS)

    Kawachi, T.; Murahashi, H.

    1991-01-01

    Techniques to build a high-quality cut-off wall have been developed for storage facilities of low-level radioactive waste (LLW) as an emergency measures to prevent leakages. The cut-off wall is highly impermeable, nucleid-adsorptive and have long-term durability. Electrophoresis is used to form impermeable membrane of bentonite as main features of the cut-off wall. First of all, laboratory tests have been conducted to study ways of building barriers on site and to collect data on the barriers properties. Afterwards, on-site construction tests of a high-quality cut-off wall have been carried out. In this paper, we describe the process and results on the studies of the high-quality cut-off wall using electrophoresis

  1. Cellulose insulation as an air barrier

    Energy Technology Data Exchange (ETDEWEB)

    Manning, K.

    1989-10-01

    The objective of this study was to determine if a wet sprayed cellulose wall insulation system would function satisfactorily without use of a polyethylene air/vapour barrier. The research was designed to demonstrate that this particular insulation system would form enough of a barrier to air leakage, that moisture accumulation from condensation and vapour diffusion would be insignificant. Field work conducted in Alberta, involved construction of a conventional duplex housing unit which was insulated with wet sprayed cellulose in the exterior walls and dry loose-fill cellulose in the attic areas. One half of the unit did not have a polyethylene air/vapor barrier installed. Air leakage and exterior wall moisture levels were monitored for a year following construction. Data collected during this time indicated that the moisture added to the walls during the insulating process was dissipated over the study period. The presence of polyethylene sheeting had no significant effect on the moisture levels in either the wall or attic areas of the test structure. On the other hand, testing indicated that the use of polyethylene sheeting in the wall system did serve to improve blower door air test results. In conclusion, although the air leakage resistance apparently provided by the polyethylene sheeting is significant, the amount is probably not more than could otherwise be obtained by more careful attention to sealing procedures such as those used in the airtight drywall technique. A more important finding is that the use of polyethylene sheeting is not essential in a structure which has the degree of air leakage resistance provided by the insulation system used in this project. 6 figs., 2 tabs.

  2. Demonstration of in situ-constructed horizontal soil containment barrier at Fernald

    International Nuclear Information System (INIS)

    Pettit, P.J.; Ridenour, D.; Walker, J.; Saugier, K.

    1994-01-01

    A new design of jet grouting tool that can be guided by horizontal well casings and that operates in the horizontal plane has been used for the in situ placement of grout and construction of a prototype horizontal barrier that is free of windows. Jet grouting techniques have been advanced to permit construction of horizontal barriers underneath contaminated soil without having to excavate or disturb the waste. The paper describes progress on the Fernald Environmental Restoration Management Corporation (FERMCO) In Situ Land Containment Project which is sponsored by the US Department of Energy's (DOE) Office of Technology Development (OTD) for DOE's Fernald Environmental Management Project (FEMP). The Fernald project is to demonstrate a novel, enabling technology for the controlled underground placement of horizontal panels of grout, and the joining of adjacent panels to construct practical, extensive barriers. Construction strategy, equipment mechanics and operating details of this new method are described

  3. SIP Shear Walls: Cyclic Performance of High-Aspect-Ratio Segments and Perforated Walls

    Science.gov (United States)

    Vladimir Kochkin; Douglas R. Rammer; Kevin Kauffman; Thomas Wiliamson; Robert J. Ross

    2015-01-01

    Increasing stringency of energy codes and the growing market demand for more energy efficient buildings gives structural insulated panel (SIP) construction an opportunity to increase its use in commercial and residential buildings. However, shear wall aspect ratio limitations and lack of knowledge on how to design SIPs with window and door openings are barriers to the...

  4. Controlling effective aspect ratio and packing of clay with pH for improved gas barrier in nanobrick wall thin films.

    Science.gov (United States)

    Hagen, David A; Saucier, Lauren; Grunlan, Jaime C

    2014-12-24

    Polymer-clay thin films constructed via layer-by-layer (LbL) assembly, with a nanobrick wall structure (i.e., clay nanoplatelets as bricks surrounded by a polyelectrolyte mortar), are known to exhibit a high oxygen barrier. Further barrier improvement can be achieved by lowering the pH of the clay suspension in the polyethylenimine (PEI) and montmorillonite (MMT) system. In this case, the charge of the deposited PEI layer is increased in the clay suspension environment, which causes more clay to be deposited. At pH 4, MMT platelets deposit with near perfect ordering, observed with transmission electron microscopy, enabling a 5× improvement in the gas barrier for a 10 PEI/MMT bilayer thin film (85 nm) relative to the same film made with pH 10 MMT. This improved gas barrier approaches that achieved with much higher aspect ratio vermiculite clay. In essence, lower pH is generating a higher effective aspect ratio for MMT due to greater induced surface charge in the PEI layers, which causes heavier clay deposition. These flexible, transparent nanocoatings have a wide range of possible applications, from food and electronics packaging to pressurized bladders.

  5. Permeable reactive barriers for pollutant removal from groundwater

    International Nuclear Information System (INIS)

    Simon, F.G.; Meggyes, T.

    2001-01-01

    The removal of pollutants from the groundwater using permeable reactive barriers is a novel in-situ groundwater remediation technology. The most relevant decontamination processes used are chemical reduction, oxidation, precipitation and sorption, for which examples are given. Some common organic pollutants are halogenated hydrocarbons, aromatic and nitroaromatic compounds which can be treated in reactive barriers successfully. Lead, chromium and, in particular, uranium are dealt with in great detail among inorganic pollutants because of their occurrence in many European countries. Construction methods for cut-off walls and reactive barriers exhibit similar features. Apart from conventional methods, drilling, deep soil mixing, jet technology, arrays of wells, injected systems and biobarriers are applied to construct permeable reactive barriers. Permeable reactive barriers bear great potential for the future in remediation engineering. (orig.)

  6. Three integrated photovoltaic/sound barrier power plants. Construction and operational experience

    International Nuclear Information System (INIS)

    Nordmann, T.; Froelich, A.; Clavadetscher, L.

    2002-01-01

    After an international ideas competition by TNC Switzerland and Germany in 1996, six companies where given the opportunity to construct a prototype of their newly developed integrated PV-sound barrier concepts. The main goal was to develop highly integrated concepts, allowing the reduction of PV sound barrier systems costs, as well as the demonstration of specific concepts for different noise situations. This project is strongly correlated with a German project. Three of the concepts of the competition are demonstrated along a highway near Munich, constructed in 1997. The three Swiss installations had to be constructed at different locations, reflecting three typical situations for sound barriers. The first Swiss installation was the world first Bi-facial PV-sound barrier. It was built on a highway bridge at Wallisellen-Aubrugg in 1997. The operational experience of the installation is positive. But due to the different efficiencies of the two cell sides, its specific yield lies somewhat behind a conventional PV installation. The second Swiss plant was finished in autumn 1998. The 'zig-zag' construction is situated along the railway line at Wallisellen in a densely inhabited area with some local shadowing. Its performance and its specific yield is comparatively low due to a combination of several reasons (geometry of the concept, inverter, high module temperature, local shadows). The third installation was constructed along the motor way A1 at Bruettisellen in 1999. Its vertical panels are equipped with amorphous modules. The report show, that the performance of the system is reasonable, but the mechanical construction has to be improved. A small trial field with cells directly laminated onto the steel panel, also installed at Bruettisellen, could be the key development for this concept. This final report includes the evaluation and comparison of the monitored data in the past 24 months of operation. (author)

  7. Airborne sound insulation of new composite wall structures

    Directory of Open Access Journals (Sweden)

    Ivanova Yonka

    2018-01-01

    Full Text Available Protection against noise is one of the essential requirements of the European Construction Product directive. In buildings, airborne sound insulation is used to define the acoustical quality between rooms. In order to develop wall structures with optimal sound insulation, an understanding of the physical origins of sound transmission is necessary. To develop a kind of knowledge that is applicable to the improvement of real walls and room barriers is the motive behind this study. The purpose of the work is to study the sound insulation of new composite wall structure.

  8. Facilitators & Barriers to the Adoption of Ergonomic Solutions in Construction

    Science.gov (United States)

    Dale, Ann Marie; Jaegers, Lisa; Welch, Laura; Barnidge, Ellen; Weaver, Nancy; Evanoff, Bradley A.

    2017-01-01

    Background Rates of musculoskeletal disorders in construction remain high. Few studies have described barriers and facilitators to the use of available ergonomic solutions. This paper describes these barriers and facilitators and their relationship to the level of adoption. Methods Three analysts rated 16 proposed ergonomic solutions from a participatory ergonomics study and assessed the level of adoption, six adoption characteristics, and identified the category of adoption from a theoretical model. Results Twelve solutions were always or intermittently used and were rated positively for characteristics of relative advantage, compatibility with existing work processes, and trialability. Locus of control (worker vs. contractor) was not related to adoption. Simple solutions faced fewer barriers to adoption than those rated as complex. Conclusions Specific adoption characteristics can help predict the use of new ergonomic solutions in construction. Adoption of complex solutions must involve multiple stakeholders, more time, and shifts in culture or work systems. PMID:28195660

  9. Construction works of large scale impervious wall in construction of No.2 plant in Onagawa Nuclear Power Station, Tohoku Electric Power Co., Inc

    International Nuclear Information System (INIS)

    Ueda, Kozaburo; Sugeno, Yoshisada; Takahashi, Hitoshi

    1991-01-01

    The main buildings for No. 2 plant in Onagawa Nuclear Power Station are constructed on the bedrocks about 14 m below the sea surface. Therefore, for the purpose of executing the works by shutting seawater off and dry work, the large scale impervious wall of about 500 m extension was installed underground. The feature of this impervious wall is the depth of embedment of about 3 m into the hard bedrocks having the uniaxial compressive strength of 2000 kg/cm 2 at maximum, carried out with the newly developed hard rock excavator. The outline of these construction works is reported. No. 2 plant in Onagawa Nuclear Power Station is the BWR plant of 825 MWe output. The construction works of the power station were began in August, 1989, and the rate of progress in civil engineering works as of the end of September, 1990 was 21.3%. The planning of the impervious wall, the geological features at the site, the method of shutting seawater off, the selection of wall materials, the design of the wall body, the investigation of the quantity of spring water, the execution of the construction and execution management, and the confirmation of the effect of the wall are reported. (K.I.)

  10. Barriers and Motivations for Construction Waste Reduction Practices in Costa Rica

    Directory of Open Access Journals (Sweden)

    Lilliana Abarca-Guerrero

    2017-12-01

    Full Text Available Low- and middle-income countries lag behind in research that is related to the construction industry and the waste problems that the sector is facing. Literature shows that waste reduction and recycling have received a continuous interest from researchers, but mainly from developed countries. Few reports from low- and middle-income countries are concerned about the reuse of masonry, concrete, and mortar in clay based building ceramics or recycling construction waste, but mostly in relation to concrete aggregates. Furthermore, few authors have described the major barriers and motivations for construction waste reduction. The objective of this paper is to report the findings on a research performed in Costa Rica with the objective to determine the barriers and motivations that the construction sector is facing to improve the management of the construction materials. The study is based on data collected in two phases. During the first phase, a survey was sent via e-mail to 419 main contractors registered at the School Federation of Engineers and Architects (CFIA. The second phase consisted of a focus group discussion with 49 professionals from the construction industry to analyse and validate the findings from the survey. Descriptive statistic methods helped to draw the conclusions. The result of the research is a comprehensive list of observed barriers and motivations for waste reduction practices in the construction sector. These are not only applicable to Costa Rica, but can be used as a guide for similar studies in other low- and middle-income countries.

  11. The role of the cell wall in plant immunity

    DEFF Research Database (Denmark)

    Malinovsky, Frederikke Gro; Fangel, Jonatan Ulrik; Willats, William George Tycho

    2014-01-01

    The battle between plants and microbes is evolutionarily ancient, highly complex, and often co-dependent. A primary challenge for microbes is to breach the physical barrier of host cell walls whilst avoiding detection by the plant's immune receptors. While some receptors sense conserved microbial...... features, others monitor physical changes caused by an infection attempt. Detection of microbes leads to activation of appropriate defense responses that then challenge the attack. Plant cell walls are formidable and dynamic barriers. They are constructed primarily of complex carbohydrates joined...... by numerous distinct connection types, and are subject to extensive post-synthetic modification to suit prevailing local requirements. Multiple changes can be triggered in cell walls in response to microbial attack. Some of these are well described, but many remain obscure. The study of the myriad of subtle...

  12. Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality

    Science.gov (United States)

    The EPA report, Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality, summarizes the research findings on the best practices for building roadside vegetative barriers to improve air quality. This fact sheet describ

  13. Analysis of administrative barriers in the industry of the high-rise construction in Russian Federation

    Science.gov (United States)

    Zaychenko, Irina; Borremans, Alexandra; Gutman, Svetlana

    2018-03-01

    The article describes the concept and types of administrative barriers encountered in various areas of the enterprise. The particularities of the Russian high-rise construction industry are described and a comparative analysis of administrative barriers in this sector is performed. The main stages and administrative procedures when the developers implement investment and construction projects in the field of high-rise construction are determined. The regulatory and legal framework for the implementation of investment and project activities in the high-rise construction industry has been studied and conclusions have been drawn on its low level of precision in the issue of the formation of competitive and efficient high-rise construction markets. The average number of administrative procedures for the implementation of the investment and construction project in the field of high-rise construction is determined. The factors preventing the reduction of administrative barriers in the high-rise construction industry are revealed.

  14. Sustainable Construction Industry in Cambodia: Awareness, Drivers and Barriers

    Directory of Open Access Journals (Sweden)

    Serdar Durdyev

    2018-02-01

    Full Text Available Although sustainability is of utmost importance, anecdotal evidence suggests that the concept is not adequately implemented in many developing countries. This paper investigates industry stakeholders’ awareness of the current state of, factors driving, and barriers hindering the adoption of sustainable construction (SC in Cambodia. Using an empirical questionnaire survey targeting local construction professionals, respondents were invited to rate their level of awareness, knowledge and understanding of SC, as well as to rate the level of importance of 31 drivers and 10 barriers identified from the seminal literature. The data set was subjected to the relative importance index method. The results suggest that the industry-wide adoption of SC practices is poor, which is believed to be due to a lack of awareness and knowledge, and reluctance to adopt new sustainable technologies. Furthermore, more efforts must be put into the selection of more durable materials for the extension of buildings’ lives and to minimize material consumption, as well as to develop energy-efficient buildings with minimal environmental impact and a healthy indoor environment, so that the ability of future generations to meet their own needs will not be compromised. The outcomes of this study have enriched knowledge about the current state of, drivers of, and barriers to sustainable construction in a typical developing economy. Although the outcomes of this study were a short scoping exercise, it has formed a significant base for future SC work within Cambodia.

  15. Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation

    Energy Technology Data Exchange (ETDEWEB)

    Arena, Lois B. [Steven Winter Associates, Inc., Norwalk, CT (United States). Consortium for Advanced Residential Buildings (CARB)

    2016-07-13

    High R-value wall assemblies (R-40 and above) are gaining popularity in the market due to programs such as the U.S. Department of Energy Zero Energy Ready Home program, Passive House, Net Zero Energy Home challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used double-wall systems to achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double-wall systems is that there are very few new exterior details. Exterior sheathings, structural bracings, house wraps or building paper, window and door flashings, and siding attachments are usually identical to good details in conventional framed-wall systems. However, although the details in double-wall systems are very similar to those in conventional stick framing, there is sometimes less room for error. Several studies have confirmed colder temperatures of exterior sheathing in high R-value wall assemblies that do not have exterior rigid foam insulation. These colder temperatures can lead to increased chances for condensation from air exfiltration, and they have the potential to result in moisture-related problems (Straube and Smegal 2009, Arena 2014, Ueno 2015). The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and reduce material brought to landfills due to failures and resulting decay. Although this document focuses on double-wall framing techniques, the majority of the information about how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture-related damage and are intended for builders, framing contractors, architects, and

  16. Barriers to Construction Health and Safety Self-regulation: A Scoping Case of Nigeria

    Directory of Open Access Journals (Sweden)

    Umeokafor Nnedinma

    2017-03-01

    Full Text Available This scoping study builds on the recent uncovering that in terms of health and safety (H&S, the Nigerian construction industry is self-regulated in various forms, not unregulated and that the size of company can further explain H&S self-regulation. Consequently, the barriers identified through literature review were assessed using questionnaires. Analysis of the data collected from construction practitioners in Nigeria shows that ‘economic factors’ mostly explains the barriers to construction H&S self-regulation. This is followed by the ‘ability to self-regulate’ and ‘lack of awareness’. Furthermore, the results show significant differences among small, medium and large construction contractors on seven factors of which include ‘normative case’ factors, ‘H&S is a duty’, ‘H&S is the right thing’ and ‘unfair H&S standards or legislation’. Although a scoping study, the study draws attention to the barriers to construction H&S self-regulation in Nigeria and demonstrates an alternative to state regulation of H&S.

  17. Partition wall structure in spent fuel storage pool and construction method for the partition wall

    International Nuclear Information System (INIS)

    Izawa, Masaaki

    1998-01-01

    A partitioning wall for forming cask pits as radiation shielding regions by partitioning inside of a spent fuel storage pool is prepared by covering both surface of a concrete body by shielding metal plates. The metal plate comprises opposed plate units integrated by welding while sandwiching a metal frame as a reinforcing material for the concrete body, the lower end of the units is connected to a floor of a pool by fastening members, and concrete is set while using the metal plate of the units as a frame to form the concrete body. The shielding metal plate has a double walled structure formed by welding a lining plate disposed on the outer surface of the partition wall and a shield plate disposed to the inner side. Then the term for construction can be shortened, and the capacity for storing spent fuels can be increased. (N.H.)

  18. Mental constructs and the cognitive reconstruction of the Berlin wall.

    Science.gov (United States)

    Tijus, C A; Santolini, A

    1996-07-01

    In this study of how to change people's conceptions of certain facts (i.e., the position of the Berlin Wall), a surprising psychological phenomenon was discovered. In the trial test, instead of designing a wall to enclose West Berlin, most people described and drew a short and straight wall that divided the city from north to south. Two methods were created, based on two general information-processing components involved in problem solving, to study how people might repair their misconceptions by themselves. The do-it-yourself method consisted of providing people with the task of thinking about how to build the wall and then drawing it, instead of just asking them to draw it. The distance-to-goal evaluation method consisted of asking the participants how the wall they had drawn would actually prevent passage from East Germany to West Berlin. The results showed that both methods had important effects in repairing misconceptions, but improvement in performance with the distance-to-goal method was less significant for those participants who were first provided the task of thinking about how to build the wall. These findings are consistent with the hypothesis that awareness of functional properties plays an important role in structuring and restructuring mental constructs.

  19. Opportunities and barriers to straw construction

    DEFF Research Database (Denmark)

    White, Caroline Meyer; Howard, Thomas J.; Lenau, Torben Anker

    2012-01-01

    During the past decades the building industry has had a great focus on energy consumption during the use phase of a building, but currently a more holistic view of the entire lifecycle of a building is starting to emerge. With this follows a greater interest in which building materials and techni......During the past decades the building industry has had a great focus on energy consumption during the use phase of a building, but currently a more holistic view of the entire lifecycle of a building is starting to emerge. With this follows a greater interest in which building materials...... and techniques of construction are considered. At the same time the request for a living environment free from toxins and allergenic substances, providing the basis for stress-free living and working conditions is increasingly demanded by clients for newly built homes. Since straw built houses supply a possible...... construction, and a series of qualitative interviews with a variety of stakeholders from previous straw build housing projects, results were gathered to find the most influential motives, barriers and considerations for straw build housing construction. Based on this empirical data, a design guide has been...

  20. Performance of engineered barriers

    International Nuclear Information System (INIS)

    Rajaram, V.; Dean, P.V.; McLellan, S.A.

    1997-01-01

    Engineered barriers, both vertical and horizontal, have been used to isolate hazardous wastes from contact, precipitation, surface water and groundwater. The primary objective of this study was to determine the performance of subsurface barriers installed throughout the U.S. over the past 20 years to contain hazardous wastes. Evaluation of Resource Conservation and Recovery Act (RCRA) Subtitle C or equivalent caps was a secondary objective. A nationwide search was launched to select hazardous waste sites at which vertical barrier walls and/or caps had been used as the containment method. None of the sites selected had an engineered floor. From an initial list of 130 sites, 34 sites were selected on the basis of availability of monitoring data for detailed analysis of actual field performance. This paper will briefly discuss preliminary findings regarding the design, construction quality assurance/construction quality control (CQA/CQC), and monitoring at the 34 sites. In addition, the short-term performance of these sites (less than 5 years) is presented since very little long-term performance data was available

  1. Study on construction technology of metro tunnel under a glass curtain wall

    Science.gov (United States)

    Zhang, Jian; Yu, Deqiang

    2018-03-01

    To ensure the safety of the glass curtain wall building above loess tunnel and get an optimal scheme, an elastic-plastic FEM model is established to simulate three reinforcement schemes based on a tunnel section in Xi’an Metro Line 3. The results show that the settlement value of the optimal scheme is reduced by 69.89% compared with the drainage measures, and the uneven settlement value is reduced by 57.5%. The construction points, technical processes and technical indexes of the optimal scheme are introduced. According to the actual project, the cumulative settlement of the building under construction is 16mm, which meets the control standards. According to the actual project, the cumulative settlement of the glass curtain wall building is 16mm, which meets the control standards. The reinforcement scheme can provide some reference for the design and construction of the metro in loess area.

  2. Thin-walled beam tubes for the SIS. Construction and manufacturing

    International Nuclear Information System (INIS)

    Malwitz, E.

    1985-06-01

    The vacuum system of the SIS consists essentially of torus-shaped vacuum chamber with an annulus-circumference of 216 m which is composed by several beam-tube and chamber elements. In order to reach the desired final pressure of -11 mbar (5 . 10 -9 Pa) a heating of the whole vacuum system to 300 0 C is required. The beam tubes within magnets have regularly an elliptic tube cross section. Within bending magnets the beam tubes are curved in a plane through the large ellipse axis with a bending radius of 10 m. During the development work for the beam tubes within magnets to construction variants were studied until construction maturity. Generally thin-walled beam tubes with elliptic tube cross section are fabricated similarly to spring bellows as corrugated tubes. In this report however beam tubes with elliptic tube cross section are discussed the tube walls of which are smooth and stabilized against the atmospheric pressure by hard-soldered ribs. The report reproduces mainly the most important know how respectively serves as instruction for new constructions. Such beam tubes are planned for the dipole magnets and the quadrupole group consisting of two long quadrupoles, a short quadrupole, and a sextupole. (orig./HSI) [de

  3. Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation

    Energy Technology Data Exchange (ETDEWEB)

    Arena, Lois B. [Steven Winter Associates, Inc., Norwalk, CT (United States). Consortium for Advanced Residential Buildings

    2016-07-13

    High-R wall assemblies (R-40 and above) are gaining popularity in the market due to programs like the DOE's Zero Energy Ready Home program, Passive House (PH), Net Zero Energy Home (NZEH) challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used 'double wall' systems to more practically achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double wall systems is that there are very few new exterior details. Exterior sheathing, structural bracing, house wrap or building paper, window and door flashing, and siding attachment are usually identical to good details in conventional framed wall systems. The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and result in a reduction of material brought to landfills due to failures and resulting decay. While this document focuses on double wall framing techniques, the majority of the information on how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture related damage and are intended for builders, framing contractors, architects, and consultants involved in designing and building super insulated homes.

  4. AN INVESTIGATION INTO THE BARRIERS FACING BLACK AND MINORITY ETHNICS WITHIN THE UK CONSTRUCTION INDUSTRY

    Directory of Open Access Journals (Sweden)

    Vian Ahmed

    2008-12-01

    Full Text Available The UK construction industry is one of the largest employers, positioned as the country’s top employer with over two million employees and projected to continue growth as far as 2011. However, it is facing ongoing skills shortages in a number of professional areas and tends to lack an ethnic diversity of workers compared to the White community of workers across the whole economy. The government’s Ethnic Minority Employment Task Force shows that for any given level of qualification, a Black or ethnic minority person is less likely to be employed, than a similarly qualified White person. Current research into issues surrounding ethnicity, from academia to employment is scarce, particularly in entry and process development within the construction industry. The aim of this paper is to outline the findings from perceptional and experiential barriers of Black and Minority Ethnics (BMEs students and employees, in order to identify perceptional and actual barriers that lead to the under-representation of BMEs within the construction industry; and also to suggest how better knowledge flow mechanisms could lead to a more balanced development, particularly in terms of ethnic diversification in the UK construction industry. The aim was achieved by adopting qualitative and quantitative methods including questionnaire surveys of undergraduate students in a construction related program, employees working within the construction industry and interviews with company directors and human resource managers. The image of the construction industry is found to be one of the major barriers for entry into the industry. Language and cultures form additional barriers for a range of ethnic groupings. Support, in the form of recruitment events, training, mentoring, professional networking, as well as work placement and experience schemes, can smooth entry, retention and progression within the construction industry.

  5. Seismic Performance of Composite Shear Walls Constructed Using Recycled Aggregate Concrete and Different Expandable Polystyrene Configurations

    Directory of Open Access Journals (Sweden)

    Wenchao Liu

    2016-03-01

    Full Text Available The seismic performance of recycled aggregate concrete (RAC composite shear walls with different expandable polystyrene (EPS configurations was investigated. Six concrete shear walls were designed and tested under cyclic loading to evaluate the effect of fine RAC in designing earthquake-resistant structures. Three of the six specimens were used to construct mid-rise walls with a shear-span ratio of 1.5, and the other three specimens were used to construct low-rise walls with a shear-span ratio of 0.8. The mid-rise and low-rise shear walls consisted of an ordinary recycled concrete shear wall, a composite wall with fine aggregate concrete (FAC protective layer (EPS modules as the external insulation layer, and a composite wall with sandwiched EPS modules as the insulation layer. Several parameters obtained from the experimental results were compared and analyzed, including the load-bearing capacity, stiffness, ductility, energy dissipation, and failure characteristics of the specimens. The calculation formula of load-bearing capacity was obtained by considering the effect of FAC on composite shear walls as the protective layer. The damage process of the specimen was simulated using the ABAQUS Software, and the results agreed quite well with those obtained from the experiments. The results show that the seismic resistance behavior of the EPS module composite for shear walls performed better than ordinary recycled concrete for shear walls. Shear walls with sandwiched EPS modules had a better seismic performance than those with EPS modules lying outside. Although the FAC protective layer slightly improved the seismic performance of the structure, it undoubtedly slowed down the speed of crack formation and the stiffness degradation of the walls.

  6. Construction Time of Three Wall Types Made of Locally Sourced Materials: A Comparative Study

    OpenAIRE

    Wojciech Drozd; Agnieszka Leśniak; Sebastian Zaworski

    2018-01-01

    Similarly to any other industry, the construction sector puts emphasis on innovativeness, unconventional thinking, and alternative ideas. At present, when sustainable development, ecology, and awareness of people’s impact on the environment grow in importance, low impact buildings can become an innovative alternative construction technology for the highly industrialized construction sector. The paper presents a comparative study of three walls made of available materials used locally, which c...

  7. Nonlinear analysis techniques of block masonry walls in nuclear power plants

    International Nuclear Information System (INIS)

    Hamid, A.A.; Harris, H.G.

    1986-01-01

    Concrete masonry walls have been used extensively in nuclear power plants as non-load bearing partitions serving as pipe supports, fire walls, radiation shielding barriers, and similar heavy construction separations. When subjected to earthquake loads, these walls should maintain their structural integrity. However, some of the walls do not meet design requirements based on working stress allowables. Consequently, utilities have used non-linear analysis techniques, such as the arching theory and the energy balance technique, to qualify such walls. This paper presents a critical review of the applicability of non-linear analysis techniques for both unreinforced and reinforced block masonry walls under seismic loading. These techniques are critically assessed in light of the performance of walls from limited available test data. It is concluded that additional test data are needed to justify the use of nonlinear analysis techniques to qualify block walls in nuclear power plants. (orig.)

  8. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik

    2010-01-01

    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding....... It was found that the specific damages made to the vapour barrier as part of the test did not have any provable effect on the moisture content. In general elements with an intact vapour barrier did not show a critical moisture content at the wind barrier after four years of exposure....

  9. In situ construction of horizontal soil containment barrier at Fernald

    International Nuclear Information System (INIS)

    Ridenour, D.; Pettit, P.J.; Walker, J.

    1995-01-01

    An innovative method of placing soil barriers to contain vertical flow is being prepared for demonstration by the Fernald Environmental Restoration Management Corporation (FERMCO), working in conjunction with the Department of Energy Office of Technology Development (DOE/OTD) and two principle subcontractors. The method employs proven directional drilling techniques, jet grouting technology and unique placement tooling to form horizontal soil barriers in situ. This is done without disturbance to existing land disposed wastes. This paper is a summary report on the current state of that demonstration, including: a discussion of the construction methods, the results of the initial tool tests, an overview of the Fernald site conditions and, the resulting path of tooling development for the second phase of tool testing

  10. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1996-05-01

    A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration was installed at a benign site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington. The composite barrier was emplaced beneath a 7,500 liter tank. The tank was chosen to simulate a typical DOE Complex waste form. The stresses induced on the waste form were evaluated during barrier construction. The barrier was constructed using conventional jet grouting techniques. Drilling was completed at a 45 degree angle to the ground, forming a conical shaped barrier with the waste form inside the cone. Two overlapping rows of cylindrical cement columns were grouted in a honeycomb fashion to form the secondary backdrop barrier layer. The primary barrier, a high molecular weight polymer manufactured by 3M Company, was then installed providing a relatively thin inner liner for the secondary barrier. The primary barrier was emplaced by panel jet grouting with a dual wall drill stem, two phase jet grouting system

  11. Construction of Barrier in a Fishing Game With Point Capture.

    Science.gov (United States)

    Zha, Wenzhong; Chen, Jie; Peng, Zhihong; Gu, Dongbing

    2017-06-01

    This paper addresses a particular pursuit-evasion game, called as "fishing game" where a faster evader attempts to pass the gap between two pursuers. We are concerned with the conditions under which the evader or pursuers can win the game. This is a game of kind in which an essential aspect, barrier, separates the state space into disjoint parts associated with each player's winning region. We present a method of explicit policy to construct the barrier. This method divides the fishing game into two subgames related to the included angle and the relative distances between the evader and the pursuers, respectively, and then analyzes the possibility of capture or escape for each subgame to ascertain the analytical forms of the barrier. Furthermore, we fuse the games of kind and degree by solving the optimal control strategies in the minimum time for each player when the initial state lies in their winning regions. Along with the optimal strategies, the trajectories of the players are delineated and the upper bounds of their winning times are also derived.

  12. Regulatory issues and assumptions associated with barriers in the vadose zone surrounding buried waste

    International Nuclear Information System (INIS)

    Siskind, B.; Heiser, J.

    1993-02-01

    One of the options for control of contaminant migration from buried waste sites is the construction of a subsurface barrier that consists of a wall of low permeability material. The barrier material should be compatible with soil and waste conditions specific to the site and have as low an effective diffusivity as is reasonably achievable to minimize or inhibit transport of moisture and contaminants. This report addresses the regulatory issues associated with the use of non-traditional organic polymer barriers as well as the use of soil-bentonite or cement-bentonite mixtures for such barriers, considering barriers constructed from these latter materials to be a regulatory baseline. The regulatory issues fall into two categories. The first category consists of issues associated with the acceptability of such barriers to the EPA as a method for achieving site or performanceimprovement. The second category encompasses those regulatory issues concerning health, safety and the environment which must be addressed regarding barrier installation and performance, especially if non-traditional materials are to be used

  13. Overcoming ICT Barriers in IBS Management Process in Malaysia Construction Industry

    Directory of Open Access Journals (Sweden)

    Soon Ern Peniel Ang

    2017-01-01

    Full Text Available As the result of government’s initiative and future outlook in uprising the awareness towards the implementation of sustainable elements in construction industries, the Industrialized Building System (IBS is one of the approaches that had been introduced as an alternative to conventional building method and produce the new strategy of reducing the waste of materials in construction. The IBS approach is actively promoted through several strategies and incentives as an alternative to conventional building methods. Extensive uptakes of modern Information Communication Technology (ICT applications are able to support the different IBS processes for effective production. However, it is argued that ICT uptake at the organizational level needs to be regularly improved. Thus, this paper fulfills the need to identify the critical barriers to ICT employment and highlighting the ICT drivers in enhancing the IBS management process. Critical barriers and drivers to ICT uptake were identified through questionnaire survey with industry stakeholders and were analyzed using mean index and critical t-value with the use of SPSS software. The critical drivers are top management support and commitment and improving the availability of the technologies. The critical drivers which were identified are significant in ensuring the enhancement of ICT implementation. Hence, any system in place should avoid the highest ranked barriers or seek to alleviate their impact by focusing on the identified drivers in order to enhance implementation of ICT in IBS process management.

  14. Containment barrier at Pride Park, Derby, England

    International Nuclear Information System (INIS)

    Barker, P.; Esnault, A.; Braithwaite, P.

    1997-01-01

    The Pride Park site at Derby occupies 96ha of derelict land close to the city centre. Approximately one third of the site was a closed landfill with a further third being an old gas works site. The remainder comprised former heavy engineering works and gravel pit workings. The River Derwent bounds the site on two sides. The objectives of the remediation strategy for the site included minimising off-site disposal of contaminated soils and ensuring that contaminants do not migrate into the adjacent river. The eastern part of the site, including the landfill and gasworks sites, was therefore contained by a 600mm wide bentonite cement vertical cut-off wall, with HDPE membrane, sealed by 1m into the underlying mudstone. The cut-off wall is some 3km long and a maximum 10m deep. The works were complicated by the need to construct the wall around 36 existing underground services. The paper briefly covers the background to the remediation of the site, describes the construction process and discusses design considerations in relation to the durability requirements of the containment barrier in the potentially aggressive environment

  15. State of the art and further development of reinforced concrete wall cells for nuclear power plant construction

    International Nuclear Information System (INIS)

    Uhlemann, E.; Wartenberg, J.

    1985-01-01

    Reinforced concrete wall cells have been developed for nuclear power plant construction by the USSR and GDR. In this article, a new type of these cells, which will be used for constructing auxiliary equipment of the Stendal nuclear power plant, is described

  16. Proteomic profiling of tissue-engineered blood vessel walls constructed by adipose-derived stem cells.

    Science.gov (United States)

    Wang, Chen; Guo, Fangfang; Zhou, Heng; Zhang, Yun; Xiao, Zhigang; Cui, Lei

    2013-02-01

    Adipose-derived stem cells (ASCs) can differentiate into smooth muscle cells and have been engineered into elastic small diameter blood vessel walls in vitro. However, the mechanisms involved in the development of three-dimensional (3D) vascular tissue remain poorly understood. The present study analyzed protein expression profiles of engineered blood vessel walls constructed by human ASCs using methods of two-dimensional gel electrophoresis (2DE) and mass spectrometry (MS). These results were compared to normal arterial walls. A total of 1701±15 and 1265±26 protein spots from normal and engineered blood vessel wall extractions were detected by 2DE, respectively. A total of 20 spots with at least 2.0-fold changes in expression were identified, and 38 differently expressed proteins were identified by 2D electrophoresis and ion trap MS. These proteins were classified into seven functional categories: cellular organization, energy, signaling pathway, enzyme, anchored protein, cell apoptosis/defense, and others. These results demonstrated that 2DE, followed by ion trap MS, could be successfully utilized to characterize the proteome of vascular tissue, including tissue-engineered vessels. The method could also be employed to achieve a better understanding of differentiated smooth muscle protein expression in vitro. These results provide a basis for comparative studies of protein expression in vascular smooth muscles of different origin and could provide a better understanding of the mechanisms of action needed for constructing blood vessels that exhibit properties consistent with normal blood vessels.

  17. Thermal performance of air-conditioned office buildings constructed with inclined walls in different climates in China

    International Nuclear Information System (INIS)

    Chan, A.L.S.; Chow, T.T.

    2014-01-01

    Highlights: • A generic fully air-conditioned office building with inclined walls was modeled. • Simulations were run under climatic conditions in three modern cities in China. • Reduction in cooling load can outweigh the increase in heating load for Hong Kong. • Inclined angle of 30° is appropriate for inverted pyramidal building in Hong Kong. • Building constructed with inclined walls is not encouraged in Shanghai and Beijing. - Abstract: An inverted pyramidal building is built with inclined walls instead of the traditional vertical façades. In terms of thermal performance, an inverted pyramidal building can provide a self-shading effect against the beam solar radiation, leading to a reduction in solar heat gain as well as building cooling load. On the other hand, the heating requirement of an inverted pyramidal building will be increased in winter. There is a strong dependency of building performance on the climatic condition. In this study, a generic air-conditioned office building with inclined walls set at different inclination angles was modeled using a building energy simulation program. Computer simulations were run to assess the thermal performance of the building constructed with inclined walls under different climatic conditions in three modern cities in China–Hong Kong, Shanghai and Beijing. The results reveal that for the building cases with inclined walls set at different inclination angles in subtropical Hong Kong, the saving in annual cooling load ranges from 0.6% to 10.9% and can outweigh the increase in heating load. Moreover, an inclination angle of 30° was found as a better design option for an inverted pyramidal building with symmetrical layout design under the climatic condition in Hong Kong. For the other two cities: Shanghai and Beijing, the saving in cooling load due to self-shading effect cannot offset the increased heating requirement. Design and construction of an inverted pyramidal building is not encouraged in these two

  18. Method of constructing shielding wall

    International Nuclear Information System (INIS)

    Nagao, Tetsuya.

    1990-01-01

    For instance, surfaces of lead particles each formed into a sphere of about 0.5 to 0.3 mm grain size are coated with a coating material of a synthetic resin comprising a polymeric material such as teflon. Subsequently, the floated lead particle are kneaded with concrete materials and then poured into a molding die by way of a hose. After coagulation, the molding die is removed to complete shielding walls in which lead particles are scattered substantially at an equal distance. In this way, since the lead particles are mixed into the shielding walls, shielding effects can be improved by so much as the lead particles are mixed, thereby enabling to reduce the thickness of the shielding walls. Further, since the lead particles are coated with the coating material, the lead particles are insulated from the concrete materials, thereby enabling to prevent the corrosion of the lead particles. Furthermore, since the lead particles and the concrete materials can be transported with ease, operation labors can be reduced. (T.M.)

  19. A new local thickening reverse spiral origami thin-wall construction for improving of energy absorption

    Science.gov (United States)

    Kong, C. H.; Zhao, X. L.; Hagiwara, I. R.

    2018-02-01

    As an effective and representative origami structure, reverse spiral origami structure can be capable to effectively take up energy in a crash test. The origami structure has origami creases thus this can guide the deformation of structure and avoid of Euler buckling. Even so the origami creases also weaken the support force and this may cut the absorption of crash energy. In order to increase the supporting capacity of the reverse spiral origami structure, we projected a new local thickening reverse spiral origami thin-wall construction. The reverse spiral origami thin-wall structure with thickening areas distributed along the longitudinal origami crease has a higher energy absorption capacity than the ordinary reverse spiral origami thin-wall structure.

  20. Sustainable Hydraulic Barrier Design Technologies for Effective Infrastructure Engineering

    Directory of Open Access Journals (Sweden)

    Chitral Wijeyesekera Devapriya

    2017-01-01

    Full Text Available Migration of liquids lead to embarrassing post construction scenarios such as that of leaks from roofs, potable water leaking from water tanks/ reservoirs, rising damp in walls with groundwater seeping into basement structures, leakage of water from ornamental lakes and ponds or leachate leakage into the environment from MSW landfill sites. Such failures demand immediate and expensive maintenance. A stringent control on structural and waterproof stability is deemed necessary for long term service life of structures and in particular underground and near surface structures. On a micro scale and over a longer time scale, the phenomenon of rising dampness occurs in older buildings with the groundwater rising up through walls, floors and masonry via capillary action. Even slower rates of contaminant fluid migration occur through landfill base liners. In this paper a variety of hydraulic barrier technologies is critically discussed against a backdrop of relevant case studies. The choice of an appropriate hydraulic barrier technology for a given scenario will depend also on the sustainability, financial affordability and subjective aesthetics.

  1. Integral Facade Construction. Towards a new product architecture for curtain walls

    Directory of Open Access Journals (Sweden)

    Tillmann Klein

    2013-06-01

    Full Text Available Curtain wall constructions are one of the most applied facade constructions today. Independently attached to the primary load bearing structure of the building they protect the building’s interior from external climate conditions and allow great design freedom. With continuously rising requirements in terms of energy savings the constructional principle has reached its limits and strategies for improvement are needed. Incrementally evolved over time it is closely related to the architectural design and building processes. Based on literature research and stakeholder interviews the dissertation maps out the traditional and craftsmanship related facade design and construction process currently employed. In a next step, future challenges for facade constructions to cope with a changing market environment are identified. A facade function tree is developed and the theory of product architecture is applied to create a comparative basis for analysing different historical and contemporary facade products and systems. The function tree as well as the analysis clearly show how the fragmented market structures has influenced contemporary facade construction and leads to extremely modular product architectures. Numerous case studies for a new approach are conducted and summarised in several matrices. The case studies show how different modular and integral constructional strategies can respond to the future challenges. The pros and cons of different facade solutions, their potential for innovation and robustness in terms of market conditions are investigated. The dissertation concludes that a greater diversity of fa.ade types with a more integral construction is needed to meet the sometimes conflicting future challenges. If this can be realised, a greater diversity of more integral design and construction processes will evolve simultaneously. The role of the different stakeholders will change and a new way of educating architects or facade specialists

  2. Croatian Experience in Road Traffic Noise Management - Concrete Noise Barriers

    Directory of Open Access Journals (Sweden)

    Ahac Saša

    2014-07-01

    Full Text Available The paper gives an overview of concrete noise barrier application in several EU countries and in Croatia. It describes a process of introducing different noise protection solutions on Croatian market in the phase of intensive motorway construction in recent years. Namely, an extensive motorway network has been constructed in Croatia in the last 10 years. Following the process of motorway construction, noise protection walls have also been erected. Usage of different building materials and installation processes as well as variations in building expenditures has led to a comparative analysis of several types of noise protection solutions (expanded clay, wood fibre including a new eco-innovative product RUCONBAR, which incorporates rubber granules from recycled waste tyres to form a porous noise absorptive layer.

  3. Three integrated photovoltaic/sound barrier power plants. Construction and operational experience; Drei integrierte PV-Schallschutz Versuchsfelder. Bau und Erprobung

    Energy Technology Data Exchange (ETDEWEB)

    Nordmann, T.; Froelich, A.; Clavadetscher, L.

    2002-07-01

    After an international ideas competition by TNC Switzerland and Germany in 1996, six companies where given the opportunity to construct a prototype of their newly developed integrated PV-sound barrier concepts. The main goal was to develop highly integrated concepts, allowing the reduction of PV sound barrier systems costs, as well as the demonstration of specific concepts for different noise situations. This project is strongly correlated with a German project. Three of the concepts of the competition are demonstrated along a highway near Munich, constructed in 1997. The three Swiss installations had to be constructed at different locations, reflecting three typical situations for sound barriers. The first Swiss installation was the world first Bi-facial PV-sound barrier. It was built on a highway bridge at Wallisellen-Aubrugg in 1997. The operational experience of the installation is positive. But due to the different efficiencies of the two cell sides, its specific yield lies somewhat behind a conventional PV installation. The second Swiss plant was finished in autumn 1998. The 'zig-zag' construction is situated along the railway line at Wallisellen in a densely inhabited area with some local shadowing. Its performance and its specific yield is comparatively low due to a combination of several reasons (geometry of the concept, inverter, high module temperature, local shadows). The third installation was constructed along the motor way A1 at Bruettisellen in 1999. Its vertical panels are equipped with amorphous modules. The report show, that the performance of the system is reasonable, but the mechanical construction has to be improved. A small trial field with cells directly laminated onto the steel panel, also installed at Bruettisellen, could be the key development for this concept. This final report includes the evaluation and comparison of the monitored data in the past 24 months of operation. (author)

  4. EVALUATION OF THERMAL INSULATION FOR THREE DIFFERENT MATERIALS USED IN CONSTRUCTION AND COMPLETION OF EXTERNAL WALLS

    Directory of Open Access Journals (Sweden)

    Marcio Carlos Navroski

    2010-05-01

    Full Text Available Summers increasingly hot are bringing large thermal problems within homes and businesses, leading to increased demand for installation of air conditioners and the consequent high energy consumption. Constructions with thermal insulation on its external walls thatcould reduce energy use or even supply the use of such equipment. Due to these factors the present study was to evaluate the insulation in three boxes built with different materials, one made of wooden boards with plain walls, and two built with plywood, wall insulation andinterior walls filled with rice husk and Styrofoam®. The boxes were built after placed in drying oven at 40 °C, then noted the temperature inside the same interval every five minutes using a digital thermometer. The box with inner Styrofoam® showed the lowest variation among the three evaluated, followed by the box of rice husk. These two materials also showed good thermal initial, unlike the box built only with wood, which showed a large interiorheating, lay in a drying oven.

  5. Barriers to the Uptake of Concurrent Engineering in the Nigerian Construction Industry

    Directory of Open Access Journals (Sweden)

    Nathaniel Anny Aniekwu

    2012-12-01

    engineering and also to compute the Kendall’s coefficient of concordance, which assess the levels of agreement among the judges on the consistency of the rankings. A Kendall’s coefficient of concordance of W=0.57365 was recorded. A lack of awareness emerged as the most important barrier against the integration of this concept into the Nigerian construction industry. The top five variables are all human factors that can be ameliorated by proper education.

  6. High-R Walls for Remodeling: Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J.; Kochkin, V.

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  7. High-R Walls for Remodeling. Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kochkin, V. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  8. Constructing bottom barriers with met grouting

    International Nuclear Information System (INIS)

    Shibazaki, M.; Yoshida, H.

    1997-01-01

    Installing a bottom barrier using conventional high pressure jetting technology and ensuring barrier continuity is challenging. This paper describes technology that has been developed and demonstrated for the emplacement of bottom barriers using pressures and flow rates above the conventional high pressure jetting parameters. The innovation capable of creating an improved body exceeding 5 meters in diameter has resulted in the satisfying connection and adherence between the treated columns. Besides, the interfaces among the improved bodies obtain the same strength and permeability lower than 1 x 10 -7 cm/sec as body itself. A wide variety of the thickness and the diameter of the improved mass optimizes the application, and the method is nearing completion. The paper explains an aspect and briefs case histories

  9. Barriers to the Development of SME's in the Australian Construction Industry

    Directory of Open Access Journals (Sweden)

    Anthony Mills

    2012-11-01

    Full Text Available Small and medium sized companies (SMEs operating in the construction industry in regionalareas of Australia often struggle to compete against city-based companies for constructionwork. This paper identifies the barriers that confront SMEs in areas outsidemajor cities, specifically in regional areas of Victoria (Australia where local firms oftencompete unsuccessfully against large Melbourne-based organisations. The authors alsolook at the possibility of using e-commerce solutions to give regional SMEs greater competitivenessas well as considering possible policy initiatives that may assist these companiesto be more successful in tendering against city-based competition.

  10. Coupling analysis on the soft ground settlement laws in Qinshan nuclear power phase I sea wall project

    International Nuclear Information System (INIS)

    Sun Feng; Pan Rong; Zhu Xiuyun; Zhang Dingli

    2011-01-01

    Qinshan Nuclear Power Phase I sea wall project is a barrier engineering in defending the design basis flooding, which is of importance to the safety of NPP. The geological condition has the feature of high compressibility and low penetration, such as the soft ground of 1 + 450 section of Qinshan Nuclear Power Phase I sea wall. Based on parameters acquired from the site experiment, 3-D finite difference analysis is put forward to study the feature of consolidation settlement laws, which can embody the fluid-solid coupling interaction. The conclusions of numerical analysis agree well with the in-site measured data, and it, can contribute to the design and construction of raising sea wall project. (authors)

  11. Dynamic wall demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Nakatsui, L.; Mayhew, W.

    1990-12-01

    The dynamic wall concept is a ventilation strategy that can be applied to a single family dwelling. With suitable construction, outside air can be admitted through the exterior walls of the house to the interior space to function as ventilation air. The construction and performance monitoring of a demonstration house built to test the dynamic wall concept in Sherwood Park, Alberta, is described. The project had the objectives of demonstrating and assessing the construction methods; determining the cost-effectiveness of the concept in Alberta; analyzing the operation of the dynamic wall system; and determining how other components and systems in the house interact with the dynamic wall. The exterior wall construction consisted of vinyl siding, spun-bonded polyolefin-backed (SBPO) rigid fiberglass sheathing, 38 mm by 89 mm framing, fiberglass batt insulation and 12.7 mm drywall. The mechanical system was designed to operate in the dynamic (negative pressure) mode, however flexibility was provided to allow operation in the static (balanced pressure) mode to permit monitoring of the walls as if they were in a conventional house. The house was monitored by an extensive computerized monitoring system. Dynamic wall operation was dependent on pressure and temperature differentials between indoor and outdoor as well as wind speed and direction. The degree of heat gain was found to be ca 74% of the indoor-outdoor temperature differential. Temperature of incoming dynamic air was significantly affected by solar radiation and measurement of indoor air pollutants found no significant levels. 4 refs., 34 figs., 11 tabs.

  12. Construction Technology and Management of Stone Curtain Wall%石材幕墙的施工工艺及施工管理

    Institute of Scientific and Technical Information of China (English)

    黄博杰

    2015-01-01

    由于石材幕墙整体效果美观,颜色均匀一致,具有较好的耐久性且不会造成玻璃幕墙所导致的光污染,目前越来越多的住宅、酒店、写字楼的外墙用石材来进行装饰。随着其广泛地运用,对石材幕墙的施工进行管理显得日益重要。该文将从石材幕墙的施工工艺及施工管理的质量、安全、进度三方面来进行分析。%Due to stone curtain wall’s merits of the overall satisfactory effect,consistent color,good durability and no light pollution generally caused by glass curtain wall,stone is increasingly widely used for the exterior wall decora-tion of residential houses,hotels and office buildings.With the wide application of stone curtain wall,the importance of the construction management of stone curtain wall is increasingly obvious.This paper briefly studies the stone cur-tain wall from aspects of the quality,safety and process of construction technology and construction management.

  13. Development of construction methods for high-density bentonite barriers using premixed spraying. Part 1. Laboratory tests on methods of spraying roughly crushed bentonite and investigation of mixing methods

    International Nuclear Information System (INIS)

    Kobayashi, Ichizo; Tanaka, Toshiyuki; Nakajima, Makoto; Toida, Masaru

    2006-01-01

    According to the present concept of geological disposal of radioactive waste, a disposal facility should consist of a bentonite-engineered barrier, a cementitious-engineered barrier, and natural barriers. To guarantee the validity of the geological disposal concept, the bentonite-engineered barrier must have high impermeability. However, an effective construction method for high-density bentonite-engineered barriers in narrow spaces such as those in radioactive waste geological disposal sites has not been developed. Therefore, the authors have developed a spraying method that has high workability in narrow spaces as a method of constructing bentonite-engineered barriers in narrow spaces. This paper describes the production method for a spraying material and an examination through spraying tests of the spraying distance, the shapes of the spray nozzles, and the ratio of spraying material to air. The test results confirmed that a bentonite-engineered barrier of dry density 1.6 Mg/m 3 could be constructed using the spraying method developed and that the appropriate spraying conditions for the construction of high-density bentonite barriers were obtained. Moreover, the authors developed a construction quality management method using the silicon oil specific-gravity method that can clearly and promptly indicate the dry density of the sprayed bentonite. (author)

  14. Composite steel panels for tornado missile barrier walls. Topical report

    International Nuclear Information System (INIS)

    1975-10-01

    A composite steel panel wall system is defined as a wall system with concrete fill sandwiched between two steel layers such that no concrete surface is exposed on the interior or the exterior wall surface. Three full scale missile tests were conducted on two specific composite wall systems. The results of the full scale tests were in good agreement with the finalized theory. The theory is presented, and the acceptance of the theory for design calculations is discussed

  15. The impact of thermal bridges on the energy demand of buildings with double brick wall constructions

    Energy Technology Data Exchange (ETDEWEB)

    Theodosiou, T.G. [Department of Engineering and Management of Energy Resources, University of Western Macedonia, GR-50100 Kozani (Greece); Papadopoulos, A.M. [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University Thessaloniki, GR-54124 Thessaloniki (Greece)

    2008-07-01

    The implementation of the European Directive on the Energy Performance of Buildings (EPBD) is a milestone towards the improvement of energy efficiency in the building sector. However, even in cases where impressive measures can be implemented in the densely built urban environment, the less glamorous measure of building's envelope thermal insulation remains a prerequisite towards the improvement of the building's energy efficiency. Despite the insulation requirements specified by national regulations, thermal bridges in the building's envelope remain a weak spot in the constructions. Moreover, in many countries construction practices tend to implement only partially the insulation measures foreseen by regulations. As a result, thermal losses are in practice greater than those predicted during the design stage. This paper presents a study on representative wall thermal insulation configurations used in Greek buildings, in order to investigate the impact of the thermal bridges on the energy consumption. The double wall construction, used widely in Greece and not only there, is rather susceptible to the occurrence of thermal bridges, in contrast to a typical thermal insulating facade, like the one applied in Central Europe. The analysis of the thermal bridges' impact will in that sense also highlight the potential for energy renovation measures in older buildings. (author)

  16. User's Guide: Computer Program for Simulation of Construction Sequence for Stiff Wall Systems With Multiple Levels of Anchors (CMULTIANC)

    National Research Council Canada - National Science Library

    Dawkins, William

    2003-01-01

    .... Top-down construction is assumed in this analysis procedure. The retaining wall system is modeled using beam on inelastic foundation methods with elastoplastic soil- pressure deformation curves (R-y curves...

  17. Target or barrier? The cell wall of early- and later- diverging plants vs cadmium toxicity: differences in the response mechanisms

    Directory of Open Access Journals (Sweden)

    Luigi eParrotta

    2015-03-01

    Full Text Available Increasing industrialization and urbanization result in emission of pollutants in the environment including toxic heavy metals, as cadmium and lead. Among the different heavy metals contaminating the environment, cadmium raises great concern, as it is ecotoxic and as such can heavily impact ecosystems. The cell wall is the first structure of plant cells to come in contact with heavy metals. Its composition, characterized by proteins, polysaccharides and in some instances lignin and other phenolic compounds, confers the ability to bind non-covalently and/or covalently heavy metals via functional groups. A strong body of evidence in the literature has shown the role of the cell wall in heavy metal response: it sequesters heavy metals, but at the same time its synthesis and composition can be severely affected. The present review analyzes the dual property of plant cell walls, i.e. barrier and target of heavy metals, by taking Cd toxicity as example. Following a summary of the known physiological and biochemical responses of plants to Cd, the review compares the wall-related mechanisms in early- and later-diverging land plants, by considering the diversity in cell wall composition. By doing so, common as well as unique response mechanisms to metal/cadmium toxicity are identified among plant phyla and discussed. After discussing the role of hyperaccumulators’ cell walls as a particular case, the review concludes by considering important aspects for plant engineering.

  18. Metals attenuation in minerally-enhanced slurry walls

    International Nuclear Information System (INIS)

    Evans, J.C.; Prince, M.J.; Adams, T.L.

    1997-01-01

    In current practice, a soil-bentonite slurry trench cutoff wall is a mixture of water, soil, and bentonite that is designed to serve as a passive barrier to ground water and contaminant transport. This study evaluated the transformation of a passive slurry trench cutoff wall barrier to an active barrier system. Conventional soil-bentonite vertical barriers presently serve as passive barriers to contaminated ground water. An active barrier will not only fulfill the functions of the present passive barrier system, but also retard contaminant transport by adsorptive processes. Attapulgite, Na-chabazite, and Ca-chabazite were added to open-quotes activateclose quotes the conventional soil-bentonite backfill. Batch extraction tests were performed to determine the partitioning coefficients of cadmium and zinc between the liquid and solid phase when in contact with the backfill mixes. Batch extraction and mathematical modeling results demonstrate the ability of an active barrier to retard the transport of cadmium and zinc. The reactivity of the soil-bentonite vertical barrier depends heavily on the inorganic being adsorbed. The reactivity of the barrier also depends on the adsorptive capabilities of the clay minerals added to the conventional soil-bentonite vertical barrier. The results of laboratory studies suggest that passive barrier systems can be transformed to active systems. Further, the data suggests that although conventional soil-bentonite vertical barriers are presently designed as passive barriers, they already have adsorptive capacity associated with active barriers

  19. NOVEL TSUNAMI BARRIERS AND THEIR APPLICATIONS FOR HYDROELECTRIC ENERGY STORAGE, FISH FARMING, AND FOR LAND RECLAMATION

    Directory of Open Access Journals (Sweden)

    Hans J. Scheel

    2014-10-01

    Full Text Available The tsunami hazard can be mitigated if the destructive waves generated from earthquakes and landslides can be reflected by a stable submerged vertical barrier before striking coastal communities or important structures. Building such deep walls by conventional submarine technology is difficult. The present study describes the principle and the erection of such submarine defensive walls by a relatively simple efficient and economic technology. This technology is based on lowering high- strength steel fences with horizontal anchors, or two parallel steel fences with distance holders, into the sea and fixing them with rocks deposited from top. Dredged material like gravel or sand can be used for additional filling. This Tsunami-Flooding Barrier (TFB extends a few meters above sea level and carries on top a concrete supply and service road protected on both sides against storm waves by concrete walls. Replaceable surge stoppers (parapets, wave return walls prevent overtopping and erosion of the seaward barrier face. The TFBs protect the coastline against tsunami and the highest storm waves from hurricanes, but also can provide protection from oil spills or other contaminations from the ocean and thus protect flora, fauna, coral reefs and beaches. Channels and gates allow navigation and can be closed quickly upon a tsunami or storm warning. The construction costs can be eventually compensated by using the reservoirs between coast and barriers for hydroelectric energy storage (using pump-turbines in the barriers or for fish-farming, or alternatively the reservoir can be filled with rocks, rubble, gravel, sand and covered with soil in order to reclaim new land. Tidal energy can be generated by installing turbines within these barriers. Also, this submarine architecture may be applied to protect pillars of bridges and offshore platforms, and for erecting “roads” into the sea to connect near-shore platforms and wind-parks with the coast and

  20. Effect of joint mechanism on vehicle redirectional capability of water-filled road safety barrier systems.

    Science.gov (United States)

    Thiyahuddin, M I; Thambiratnam, D P; Gu, Y T

    2014-10-01

    Portable water-filled barriers (PWFBs) are roadside appurtenances that prevent vehicles from penetrating into temporary construction zones on roadways. PWFBs are required to satisfy the strict regulations for vehicle re-direction in tests. However, many of the current PWFBs fail to re-direct the vehicle at high speeds due to the inability of the joints to provide appropriate stiffness. The joint mechanism hence plays a crucial role in the performance of a PWFB system at high speed impacts. This paper investigates the desired features of the joint mechanism in a PWFB system that can re-direct vehicles at high speeds, while limiting the lateral displacement to acceptable limits. A rectangular "wall" representative of a 30m long barrier system was modeled and a novel method of joining adjacent road barriers was introduced through appropriate pin-joint connections. The impact response of the barrier "wall" and the vehicle was obtained and the results show that a rotational stiffness of 3000kNm/rad at the joints seems to provide the desired features of the PWFB system to re-direct impacting vehicles and restrict the lateral deflection. These research findings will be useful to safety engineers and road barrier designers in developing a new generation of PWFBs for increased road safety. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Air Leakage Rates in Typical Air Barrier Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Hun, Diana E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Atchley, Jerald Allen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Childs, Phillip W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-11-01

    Estimates for 2010 indicate that infiltration in residential buildings was responsible for 2.85 quads of energy (DOE 2014), which is about 3% of the total energy consumed in the US. One of the mechanisms being implemented to reduce this energy penalty is the use of air barriers as part of the building envelope. These technologies decrease airflow through major leakage sites such as oriented strand board (OSB) joints, and gaps around penetrations (e.g., windows, doors, pipes, electrical outlets) as indicated by Hun et al. (2014). However, most air barrier materials do not properly address leakage spots such as wall-to-roof joints and wall-to-foundation joints because these are difficult to seal, and because air barrier manufacturers usually do not provide adequate instructions for these locations. The present study focuses on characterizing typical air leakage sites in wall assemblies with air barrier materials.

  2. DISCOURSE, REFERENCIATION AND CONSTRUCTION OF POLITICAL IDENTITY: THE CASE OF OCCUPY WALL STREET

    Directory of Open Access Journals (Sweden)

    Thaysa Maria Braide de Moraes Cavalcante

    2016-12-01

    Full Text Available This article aims to undertake an analysis of identity construction of the Occupy Wall Street (OWS, North American movement that opposed the financial policy of capitalism and, consequently, the strong influence of the capital of the State. Thus, we aim to answer the question of how does the discursive construction of identity of this object of discourse, from the referential strategies mobilized in the text of the Statement of Autonomy, document approved by the General Assembly of movement. Our theoretical and methodological support consists of a link between the theory of discourse, the political scientist Ernesto Laclau (1990, 2011; LACLAU; MOUFFE, 2001 – especially his remarks about the relationship between discourse, antagonism and construction of political identities through an equivalence of logic –, and studies of referentiation from the perspective of authors such as Apothéloz e Reichler-Béguelin (1995, Koch (2005, 2015, Marcuschi (2007 e Ciulla e Silva (2008. Using as textual analysis category anaphoric expressions – without neglecting other elements, like some deictics, that interfere in the construction process of the discourse object in question – we attention to the fact that this construction sets the OWS as what Laclau calls empty significant whose identity is carved through the formation and expansion of a chain of equivalence, which is established from an antagonistic relationship. Finally, we discuss some issues concerning this identity construction mode in order to face the language not only as a way of materialization of social tensions but as the privileged place of social struggles brought about by these tensions.

  3. Mitigation of Traffic-Induced Ground Vibration by Inclined Wave Barriers

    DEFF Research Database (Denmark)

    Andersen, Lars; Augustesen, Anders Hust

    2009-01-01

    Double sheet pile walls can be used as wave barriers in order to mitigate ground vibrations from railways. The present analysis concerns the efficiency of such barriers, especially with regard to the influence of the barrier inclination and the backfill between the walls. Thus, the screening capa...... of reference following the load. This allows a computation of the steady state response to a harmonically varying point source moving at different speeds typical for a train....

  4. Regulatory issues and assumptions associated with polymers for subsurface barriers surrounding buried waste

    International Nuclear Information System (INIS)

    Heiser, J.; Siskind, B.

    1993-01-01

    One of the options for control of contaminant migration from buried waste sites is the construction of a subsurface barrier that consists of a wall of low permeability material. Subsurface barriers will improve remediation performance by removing pathways for contaminant transport due to groundwater movement, meteorological water infiltration, vapor- and gas-phase transport, transpiration, etc. Subsurface barriers may be used to open-quotes directclose quotes contaminant movement to collection sumps/lysimeters in cases of unexpected remediation failures or transport mechanisms, to contain leakage from underground storage tanks, and to restrict in-situ soil cleanup operation and chemicals. Brookhaven National Laboratory is currently investigating advanced polymer materials for subsurface barriers. This report addresses the regulatory aspects of using of non-traditional polymer materials as well as soil-bentonite or cement-bentonite mixtures for such barriers. The regulatory issues fall into two categories. The first category consists of issues associated with the acceptability of subsurface barriers to the Environmental Protection Agency (EPA) as a method for achieving waste site performance improvement. The second category encompasses those regulatory issues concerning health, safety and the environment which must be addressed regarding barrier installation and performance, especially if non-traditional materials are to be used. Since many of EPA's concerns regarding subsurface barriers focus on the chemicals used during installation of these barriers the authors discuss the results of a search of the Federal Register and the Code of Federal Regulations for references in Titles 29 and 40 pertaining to key chemicals likely to be utilized in installing non-traditional barrier materials. The use of polymeric materials in the construction industry has been accomplished with full compliance with the applicable health, safety, and environmental regulations

  5. Evolution of building envelope construction techniques in coastal British Columbia

    Energy Technology Data Exchange (ETDEWEB)

    Mattock, C.; Ito, K.; Oshikawa, T. [International Eco-House Inc., (Canada)

    1999-11-01

    Changes in the significant evolutionary development over the past 3 years in building envelope construction for multi storey wood frame housing in British Columbia are described. The urban areas of this region are characterized by a maritime climate which features a high frequency of wind driven rain and little accumulation of snow. Buildings are exposed to high wetting with little drying potential, and moderate temperatures allow for fungal growth even in the winter. While as in the rest of Canada wetting is often due to condensation of moisture contained in indoor air as it leaks out of the building, in British Columbia wind driven rain is a much larger source of moisture. Given this, the following principles of moisture control have been promoted to the B.C. building industry in order of priority: 1) deflection - using parts and elements of the building such as overhangs and flashings that reduce the exposure of the exterior walls to rain, 2) drainage - using envelope assemblies that will then redirect liquid water to the outside, 3) employing drying elements that promote drying through diffusion such as highly permeable wall sheathings, and 4) use of durable materials - using materials that resist rot such as treated lumber, stainless steel fastenings, etc. A variety of air barrier systems other than the conventional sealed polyethylene approach have been employed because of the introduction of recent building code requirements for enhanced airtightness and air barrier durability combined with the use of rain screen construction. This variety of air barrier systems includes: an airtight drywall, an exterior permeable membrane, and an exterior impermeable membrane.

  6. Emotional Benefits and Barriers of Psychological Services Scale: Initial construction and validation among African American women.

    Science.gov (United States)

    Watson-Singleton, Natalie N; Okunoren, Oladoyin; LoParo, Devon; Hunter, Carla D

    2017-11-01

    The current study used the Health Belief Model to develop a measure that assessed the emotional benefits and barriers of professional psychological services in an African American women sample. Data from 251 African American women recruited from online organizations from across the United States (n = 164) and a Midwestern university psychology subject pool (n = 87) were used for exploratory factor analysis. Results revealed a 2-factor structure of the Emotional Benefits and Barriers of Psychological Services (EBBPS) Scale: Life Enhancement and Concerns about Distress, respectively. Confirmatory factor analysis was performed with data from 208 African American women who were recruited from a Midwestern university psychology subject pool (n = 81), Mturk (n = 104), and online organizations across the United States (n = 23). Results confirmed the EFA 2-factor model and demonstrated superior fit compared with a unidimensional model as well as a 3 factor model. Both factors exhibited excellent internal consistency. Construct validity was supported given that EBBPS factors were correlated with theoretically related constructs, like psychological help-seeking attitudes, intentions to seek counseling, and cultural identity, as well as uncorrelated with theoretically unrelated constructs, like psychological distress. These findings support the utility and cultural relevance of the EBBPS with African American women. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Detecting defects in diaphragm walls prior to excavation

    NARCIS (Netherlands)

    Spruit, R.; Hopman, V.; Van Tol, A.F.; Broere, W.

    2011-01-01

    Recent incidents with leaking diaphragm walls during construction of subway lines in Amsterdam and Rotterdam (Netherlands) have led to reconsideration of the diaphragm wall as a retaining wall construction for deep excavations. In our opinion the joints between the panels are the weak spot. During

  8. Diaphragm walling for Sizewell B sets records

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The first phase of construction of the Sizewell-B nuclear reactor has been completed. This was the building of a diaphragm wall around the site. It is one of the largest and deepest diaphragm walls to be installed in Europe. The site can be pumped dry of groundwater and the foundations constructed in the dry. The specifications of the wall and its construction, using two Hydrofraise excavation rigs, are described. The excavated material is brought up as a slurry and the (bentonite) slurry is cleaned and desanded. Most of the wall has been formed using a plastic concrete but reinforced concrete has been used for some stretches. The diaphragm wall, which is 1258m long and 55m deep on average, was built in 19 weeks. (U.K.)

  9. Feasibility of permeation grouting for constructing subsurface barriers

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1994-03-01

    The technical feasibility of emplacing a barrier beneath a waste site using directionally drilled boreholes and permeation grouting was investigated. The benefits of this emplacement system are: (1) Directionally drilled boreholes provide access beneath a waste site without disturbing the waste; (2) interim containment of contaminants allows time for the development of remediation options; (3) in the interim, the volume of waste remains fixed; (4) barriers may enhance the effectiveness of in situ remediation actions; and (5) barrier systems may provide permanent waste containment

  10. Transport barriers in plasmas

    International Nuclear Information System (INIS)

    Caldas, I L; Szezech, J D Jr; Kroetz, T; Marcus, F A; Roberto, M; Viana, R L; Lopes, S R

    2012-01-01

    We discuss the creation of transport barriers in magnetically confined plasmas with non monotonic equilibrium radial profiles. These barriers reduce the transport in the shearless region (i.e., where the twist condition does not hold). For the chaotic motion of particles in an equilibrium electric field with a nonmonotonic radial profile, perturbed by electrostatic waves, we show that a nontwist transport barrier can be created in the plasma by modifying the electric field radial profile. We also show non twist barriers in chaotic magnetic field line transport in the plasma near to the tokamak wall with resonant modes due to electric currents in external coils.

  11. Building America Case Study: Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation, Cold Climate Region

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    High-R wall assemblies (R-40 and above) are gaining popularity in the market due to programs like the DOE's Zero Energy Ready Home program, Passive House (PH), Net Zero Energy Home (NZEH) challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used 'double wall' systems to more practically achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double wall systems is that there are very few new exterior details. Exterior sheathing, structural bracing, house wrap or building paper, window and door flashing, and siding attachment are usually identical to good details in conventional framed wall systems. The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and result in a reduction of material brought to landfills due to failures and resulting decay. While this document focuses on double wall framing techniques, the majority of the information on how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture related damage and are intended for builders, framing contractors, architects, and consultants involved in designing and building super insulated homes.

  12. Large-scale field testing on flexible shallow landslide barriers

    Science.gov (United States)

    Bugnion, Louis; Volkwein, Axel; Wendeler, Corinna; Roth, Andrea

    2010-05-01

    Open shallow landslides occur regularly in a wide range of natural terrains. Generally, they are difficult to predict and result in damages to properties and disruption of transportation systems. In order to improve the knowledge about the physical process itself and to develop new protection measures, large-scale field experiments were conducted in Veltheim, Switzerland. Material was released down a 30° inclined test slope into a flexible barrier. The flow as well as the impact into the barrier was monitored using various measurement techniques. Laser devices recording flow heights, a special force plate measuring normal and shear basal forces as well as load cells for impact pressures were installed along the test slope. In addition, load cells were built in the support and retaining cables of the barrier to provide data for detailed back-calculation of load distribution during impact. For the last test series an additional guiding wall in flow direction on both sides of the barrier was installed to achieve higher impact pressures in the middle of the barrier. With these guiding walls the flow is not able to spread out before hitting the barrier. A special constructed release mechanism simulating the sudden failure of the slope was designed such that about 50 m3 of mixed earth and gravel saturated with water can be released in an instant. Analysis of cable forces combined with impact pressures and velocity measurements during a test series allow us now to develop a load model for the barrier design. First numerical simulations with the software tool FARO, originally developed for rockfall barriers and afterwards calibrated for debris flow impacts, lead already to structural improvements on barrier design. Decisive for the barrier design is the first dynamic impact pressure depending on the flow velocity and afterwards the hydrostatic pressure of the complete retained material behind the barrier. Therefore volume estimation of open shallow landslides by assessing

  13. Masonry calendar 1989. A handbook on masonry, wall construction materials, sound, thermal and moisture insulation. Mauerwerk-Kalender 1989. Taschenbuch fuer Mauerwerk, Wandbaustoffe, Schall-, Waerme- und Feuchtigkeitsschutz

    Energy Technology Data Exchange (ETDEWEB)

    Funk, P [ed.

    1989-01-01

    The 1989 Masonry Calendar comprises the following sections and contibutions: Harmonisation of technical rules for brickwork construction on a European scale; fundamentals for brickwork dimensioning according to DIN 1053, part 2; exemplary calculations for the dimensioning of brick walls under compressive and shearing loads according to DIN 1053, part 2; calculation aids for brickwork dimensioning according to DIN 1053, part 2; dimensioning tables for reinforced brickwork of rectangular cross section; characteristic data of brickwork, bricks, and mortar; thermal insulation of brickwork; moisture protection problems in brickwork construction; noise abatement in brickwork construction; novel materials and designs in brickwork construction; characteristic data for calculating the thermal conductivity of building materials; regulations on construction, bricks, binders; further construction materials, testing standards, constructional physics, further standards and technical regulations for brickwork construction, with supplements; DGfM codes; work scaffolding; dwelling on brickwork construction; experiments on the seismic response of brickwork; supporting strength of brick walls under simultaneous horizontal and vertical stress; masonry cost calculation in the framework of overall construction cost calculation; bibliography and important addresses. (BR).

  14. Research Status of the Skeletalre Construction of Chest Wall

    Directory of Open Access Journals (Sweden)

    Daixing ZHONG

    2018-04-01

    Full Text Available Chest wall defect may be caused by many factors such as the resection of tumor and trauma, and the reconstruction of bone-defection is still the key point of thoracic surgery. With the development of material science, more and more new materials have been used in medical practice, which makes huge progress in the surgery of chest wall. However, none of these materials satisfy all the practical needs of the reconstruction. Recently, with the development of the capacity of computer, 3D-printing technology has been gradually used in clinical work, and the idea of individual treatment has been accepted by more and more people. The weakness of these materials may be solved by the new material and the application of individual treatment, which could also make great advance in chest wall surgery. This article will make a summary of the research on the reconstruction of chest wall.

  15. The southern gate of the walled city of León, Spain (I-XII centuries. Stratigraphic and interpretive analysis of a new constructive evidence

    Directory of Open Access Journals (Sweden)

    Ángel Morillo

    2017-09-01

    Full Text Available In 2000 took place the discovery of a large wall ashlar, actually integrated into the basement of a shop in the historic town of León (Spain. The typology of his constructive system and its topographic position into the plan of the town, allow us to identify it as the front of one of the flanking towers of the southern gate (porta praetoria of the roman legionary fortress of legio VII gemina. This camp was built at the end of the first century-early second century AD. The wall has many architectural reforms and adjustments. Their analysis testifies its evolution between Early Roman Empire and the twelfth and thirteenth centuries AD. The analysis of the mural stratigraphy presented here show the relative chronologies of different masonry and constructive activities determining the diachronic development of the construction. We can also clarify historical aspects about the south wall of León. The data obtained have been compared with three-dimensional topographic space in which are found, illustrating on the evolution of the urban landscape.

  16. A design and construction of wire drive mechanical barrier system on the medium dose brachytherapy for cervical cancer

    International Nuclear Information System (INIS)

    Nur Khasan; Tri Harjanto; Ari Satmoko

    2012-01-01

    A design and construction of wire drive mechanical barrier system on the medium dose brachytherapy for cervical cancer has been done as a complete system for security of both mechanically and electrically during the operation of the device as a whole. The design and construction were carried out by paying attention to the length of wire dimensions, the diameter of the roller drum for wire, the process of wire rolling and delivery path length of the radioactive source or also the checker. The length dimension of wire or delivery path length with a diameter of drum rollers which is converted into 2 pieces of limiting the size of the circular line on the gear system is integrated with the limit switch/divider electrically. By using this barrier the security and certainty of the wire rolling and delivery process are assured, either wire of radioactive sources or also wire of checker. The materials or components used are aluminum for gear system and limit switches for electrical systems. The result of the construction is a set of equipment that is used to complete a safety facility operating on the wire drive module of medium dose brachytherapy for cervical cancer. (author)

  17. Ambiguous walls

    DEFF Research Database (Denmark)

    Mody, Astrid

    2012-01-01

    The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how walls...... have encouraged architectural thinking of enclosure, materiality, construction and inhabitation in architectural history, the paper’s aim is to define new directions for the integration of LEDs in walls, challenging the thinking of inhabitation and program. This paper introduces the notion...... of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...

  18. [Construction and validation of a short scale of perception of barriers for the physical activity in adolescents].

    Science.gov (United States)

    Cabanas-Sánchez, Verónica; Tejero-González, Carlos M; Veiga, Oscar L

    2012-01-01

    One of the main problems of health in the first world is the increase of physical inactivity. In this respect, adolescence has been identified as a critic period with high decline of physical activity. Therefore, a relevant line of research is the understanding of this social phenomenon. The aim of this study was to design a scale to assess perceived barriers to physical activity on adolescents. A convenience sample of 160 Spanish adolescents (84 girls), between 12 and 18 years old, was recruited for this study. Firstly, there were designed 40 items whose pertinence was evaluated through content validation by experts. Later, the participants were divided in two randomized groups, and Exploratory Factor Analysis and Confirmatory Factor Analysis were performed to define a short scale of 12 items. Cronbach Alfa Coefficent was used to evaluate internal consistence of the instrument. The scale reports four dimensions: incompatibility barriers (2 items), self-concept barriers (4 items), amotivation barriers (4 items) and social barriers (2 items). The scale showed enough construct validity (χ2=60.78; d.f.=48; p=0.100; GFI=0.88; CFI=0.94; RMSEA=0.58) and high internal reliability (α=0.80). Moreover, the scale was able to explain 67% of the data variance. The Short Scale of Perceived Barriers to Physical Activity in Adolescents is a valid and reliable instrument.

  19. Resonant tunneling across a ferroelectric domain wall

    Science.gov (United States)

    Li, M.; Tao, L. L.; Velev, J. P.; Tsymbal, E. Y.

    2018-04-01

    Motivated by recent experimental observations, we explore electron transport properties of a ferroelectric tunnel junction (FTJ) with an embedded head-to-head ferroelectric domain wall, using first-principles density-functional theory calculations. We consider a FTJ with L a0.5S r0.5Mn O3 electrodes separated by a BaTi O3 barrier layer and show that an in-plane charged domain wall in the ferroelectric BaTi O3 can be induced by polar interfaces. The resulting V -shaped electrostatic potential profile across the BaTi O3 layer creates a quantum well and leads to the formation of a two-dimensional electron gas, which stabilizes the domain wall. The confined electronic states in the barrier are responsible for resonant tunneling as is evident from our quantum-transport calculations. We find that the resonant tunneling is an orbital selective process, which leads to sharp spikes in the momentum- and energy-resolved transmission spectra. Our results indicate that domain walls embedded in FTJs can be used to control the electron transport.

  20. Moisture Performance of Energy-Efficient and Conventional Wood-Frame Wall Assemblies in a Mixed-Humid Climate

    Directory of Open Access Journals (Sweden)

    Samuel V. Glass

    2015-07-01

    Full Text Available Long-term moisture performance is a critical consideration for design and construction of building envelopes in energy-efficient buildings, yet field measurements of moisture characteristics for highly insulated wood-frame walls in mixed-humid climates are lacking. Temperature, relative humidity, and moisture content of wood framing and oriented strand board (OSB structural panel sheathing were measured over a period from mid-November 2011 through March 2013 in both north- and south-facing orientations in test structures near Washington, DC, USA. Wall configurations varied in exterior cladding, water-resistive barrier, level of cavity insulation, presence of exterior continuous insulation, and interior vapor retarder. The combination of high interior humidity and high vapor permeance of painted gypsum board led to significant moisture accumulation in OSB sheathing during winter in walls without a vapor retarder. In contrast, wintertime moisture accumulation was not significant with an interior kraft vapor retarder. Extruded polystyrene exterior insulation had a predictable effect on wall cavity temperature but a marginal impact on OSB moisture content in walls with vinyl siding and interior kraft vapor retarder. Hygrothermal simulations approximately captured the timing of seasonal changes in OSB moisture content, differences between north- and south-facing walls, and differences between walls with and without an interior kraft vapor retarder.

  1. Summary report on close-coupled subsurface barrier technology: Initial field trials to full-scale demonstration

    International Nuclear Information System (INIS)

    Heiser, J.H.

    1997-09-01

    The primary objective of this project was to develop and demonstrate the installation and measure the performance of a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional, low-cost, cement-grout containment barrier followed by a thin lining of a polymer grout. The resultant barrier is a cement-polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. The technology has matured from a regulatory investigation of the issues concerning the use of polymers to laboratory compatibility and performance measurements of various polymer systems to a pilot-scale, single column injection at Sandia to full-scale demonstration. The feasibility of the close-coupled barrier concept was proven in a full-scale cold demonstration at Hanford, Washington and then moved to the final stage with a full-scale demonstration at an actual remediation site at Brookhaven National Laboratory (BNL). At the Hanford demonstration the composite barrier was emplaced around and beneath a 20,000 liter tank. The secondary cement layer was constructed using conventional jet grouting techniques. Drilling was completed at a 45 degree angle to the ground, forming a cone-shaped barrier. The primary barrier was placed by panel jet-grouting with a dual-wall drill stem using a two part polymer grout. The polymer chosen was a high molecular weight acrylic. At the BNL demonstration a V-trough barrier was installed using a conventional cement grout for the secondary layer and an acrylic-gel polymer for the primary layer. Construction techniques were identical to the Hanford installation. This report summarizes the technology development from pilot- to full-scale demonstrations and presents some of the performance and quality achievements attained

  2. Safety- barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2008-01-01

    Safety-barrier diagrams and the related so-called 'bow-tie' diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation of safety-barrier diagrams to other methods such as fault...... trees and Bayesian networks is discussed. A simple method for quantification of safety-barrier diagrams is proposed. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management....

  3. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

    Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk...... analysis with operational safety management....

  4. To detect anomalies in diaphragm walls

    NARCIS (Netherlands)

    Spruit, R.

    2015-01-01

    Diaphragm walls are potentially ideal retaining walls for deep excavations in densely built-up areas, as they cause no vibrations during their construction and provide structural elements with high strength and stiffness. In the recent past, however, several projects using diaphragm walls as soil

  5. CONSTRUCTIVE ASPECTS INFLUENCE ON STIFFNESS OF DIAPHRAGM WALLS IN FRAME CONSTRUCTIONS WITH (LIGHT STEEL THIN –WALLED STRUCTURES

    Directory of Open Access Journals (Sweden)

    M. V. Savytskyi

    2010-10-01

    Full Text Available The dependences of influence of structural features of diaphragms of lightweight steel framing braced wall structures on their stiffness are determined. On the basis of dependences the procedure for estimation of stiffness of a diaphragm of any configuration that allows making decisions for maintenance of building stiffness is developed.

  6. Use of flexible facing for soil nail walls.

    Science.gov (United States)

    2011-11-01

    Soil nail walls are a widely used technology for retaining vertical and nearly vertical cuts in soil. A : significant portion of the cost of soil nail wall construction is related to the construction of a reinforced : concrete face. The potential for...

  7. Dismountable wall for radiation shielding and screen realized from this wall

    International Nuclear Information System (INIS)

    Blomart, P.

    1988-01-01

    The wall for protection against neutrons and gamma radiations is made of bricks with a shoulder on the upper and side faces and the complementary shape on the lower face to provide a barrier to radiations. Bricks are made of a heavy material for gamma absorption and of epoxy resin, boric acid and hydrated alumina [fr

  8. Analysis on the construction technology of stone curtain wall in building engineering%谈钢结构技术在土木工程施工中的应用

    Institute of Scientific and Technical Information of China (English)

    齐鑫

    2016-01-01

    This paper introduced the construction characteristics of stone curtain wall,from the positioning,lightning protection connection,stone panel installation,pendant installation and other aspects,elaborated the construction technology of stone curtain wall,and discussed the methods to improve the construction quality,conducive to promote the popularization and application of stone curtain wall.%结合实践经验,分析了土木工程中钢结构施工技术存在的问题,并从吊装施工、焊接技术、现场勘测、材料选择四方面,提出了改进钢结构施工技术的建议,从而提高钢结构的施工水平。

  9. Wall Finishes; Carpentry: 901895.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    The course outline is designed to provide instruction in selecting, preparing, and installing wall finishing materials. Prerequisites for the course include mastery of building construction plans, foundations and walls, and basic mathematics. Intended for use in grades 11 and 12, the course contains five blocks of study totaling 135 hours of…

  10. Energy conservation and recycling of wall and concrete may give large environmental profits in the construction industry. Environment taken seriously

    International Nuclear Information System (INIS)

    Nestvold, Veslemoey

    2000-01-01

    The article reviews some results from the 5 year project ''Oekobygg'', started in 1998, which studies energy conservation and recycling of wall and concrete in the construction industry. Reduction of the waste amounts, industrial recycling and ''smart housing'' are discussed. Recycling will result in the largest environmental benefits

  11. Research on Reasons for Repeated Falling of Tiles in Internal Walls of Construction

    Science.gov (United States)

    Xu, LiBin; Chen, Shangwei; He, Xinzhou; Zhu, Guoliang

    2018-03-01

    In view of the quality problem of repeated falling of facing tiles in some construction, the essay had a comparative trial in laboratory on cement mortar which is often used to paste tiles, special tile mortar and dry-hang glue, and measured durability of tile adhesive mortar through freezing and thawing tests. The test results indicated that ordinary cement mortar cannot meet standards due to reasons like big shrinkage and low adhesive. In addition, the ten times of freezing and thawing tests indicated that ordinary cement mortar would directly shell and do not have an adhesive force, and moreover, adhesive force of special tile mortar would reduce. Thus, for tiles of large size which are used for walls, dry-hang techniques are recommended to be used.

  12. Contributing to Net Zero Building: High Energy Efficient EIFS Wall Systems

    Energy Technology Data Exchange (ETDEWEB)

    Carbary, Lawrence D. [Dow Corning Corporation; Perkins, Laura L. [Dow Corning Corporation; Serino, Roland [Dryvit Systems, Inc; Preston, Bill [Dryvit Systems, Inc; Kosny, Jan [Fraunhofer USA, Inc. CSE

    2014-01-29

    The team led by Dow Corning collaborated to increase the thermal performance of exterior insulation and finishing systems (EIFS) to reach R-40 performance meeting the needs for high efficiency insulated walls. Additionally, the project helped remove barriers to using EIFS on retrofit commercial buildings desiring high insulated walls. The three wall systems developed within the scope of this project provide the thermal performance of R-24 to R-40 by incorporating vacuum insulation panels (VIPs) into an expanded polystyrene (EPS) encapsulated vacuum insulated sandwich element (VISE). The VISE was incorporated into an EIFS as pre-engineered insulation boards. The VISE is installed using typical EIFS details and network of trained installers. These three wall systems were tested and engineered to be fully code compliant as an EIFS and meet all of the International Building Code structural, durability and fire test requirements for a code compliant exterior wall cladding system. This system is being commercialized under the trade name Dryvit® Outsulation® HE system. Full details, specifications, and application guidelines have been developed for the system. The system has been modeled both thermally and hygrothermally to predict condensation potential. Based on weather models for Baltimore, MD; Boston, MA; Miami, FL; Minneapolis, MN; Phoenix, AZ; and Seattle, WA; condensation and water build up in the wall system is not a concern. Finally, the team conducted a field trial of the system on a building at the former Brunswick Naval Air Station which is being redeveloped by the Midcoast Regional Redevelopment Authority (Brunswick, Maine). The field trial provided a retrofit R-30 wall onto a wood frame construction, slab on grade, 1800 ft2 building, that was monitored over the course of a year. Simultaneous with the façade retrofit, the building’s windows were upgraded at no charge to this program. The retrofit building used 49% less natural gas during the winter of

  13. External walls made of solar Lego bricks. Sulfurcell head office building: External wall construction according to the dimensions of Sulfurcell solar modules; Solare Legosteinfassade. Die Masse der hauseigenen Module bildeten den Ausgangspunkt fuer die Planung des Sulfurcell-Hauptquartiers

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Neelke

    2009-11-15

    The Sulfurcell Solartechnik GmbH constructed a new office building at Berlin-Adlershof. The building's external walls were designed on the basis of the frameless Sulfurcell standard module. The building intends to prove that solar modules are not a luxury item but an efficient and easy-to-handle constructional material. (orig.)

  14. Thermal insulation properties of walls

    Directory of Open Access Journals (Sweden)

    Zhukov Aleksey Dmitrievich

    2014-05-01

    Full Text Available Heat-protective qualities of building structures are determined by the qualities of the used materials, adequate design solutions and construction and installation work of high quality. This rule refers both to the structures made of materials similar in their structure and nature and mixed, combined by a construction system. The necessity to ecaluate thermal conductivity is important for a product and for a construction. Methods for evaluating the thermal protection of walls are based on the methods of calculation, on full-scale tests in a laboratory or on objects. At the same time there is a reason to believe that even deep and detailed calculation may cause deviation of the values from real data. Using finite difference method can improve accuracy of the results, but it doesn’t solve all problems. The article discusses new approaches to evaluating thermal insulation properties of walls. The authors propose technique of accurate measurement of thermal insulation properties in single blocks and fragments of walls and structures.

  15. Design and construction of a system for determination of Radon-222 by a surface-barrier detector

    International Nuclear Information System (INIS)

    Bonifacio M, J.; Iturbe, J.L.

    1993-01-01

    In the present work the design and construction of a system for the determination of 222 Rn is described, which utilizes silicon surface-barrier detectors. The 222 Rn gas was obtained a source of 226 Ra electrodeposited on stainless-steel discs. The well separated energies with this system makes possible the measurement and identification of alpha particles of 222 Rn, and its daughters 210 Po, 218 Po and 214 Po. (Author) 3 figs, 19 refs

  16. Organic Insulation Materials, the Effect on Indoor Humidity, and the Necessity of a Vapor Barrier

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Examples of organic insulation products are cellulose fiber, other plant fiber, and animal wool. These materials, which are all very hygroscopic, are associated with certain assertions about their building physical behavior that need to be verified.Examples of such assertions are: "A vapor barrier...... is not needed when using organic insulation materials" and "Organic insulation materials have a stabilizing effect on the indoor humidity".The paper presents some numerical analyses of the hygrothermal behavior of wall constructions and the occupied spaces they surround when an organic insulation material...

  17. Lining bunker walls with oxygen barrier film reduces nutrient losses in corn silages.

    Science.gov (United States)

    Lima, L M; Dos Santos, J P; Casagrande, D R; Ávila, C L S; Lara, M S; Bernardes, T F

    2017-06-01

    The objective of this study was to evaluate 2 systems for covering corn silage in bunker silos. The first system consisted of a sheet of 45-μm-thick oxygen barrier film (OB, polyethylene + ethylene-vinyl alcohol) placed along the length of the sidewall before filling. After filling, the excess film was pulled over the wall on top of the silage, and a sheet of polyethylene was placed on top. The second system involved using a standard sheet (ST) of 180-μm-thick polyethylene film. Eight commercial bunker silos were divided into 2 parts lengthwise so that one-half of the silo was covered with OB and the other half with a ST system. During the filling, 3 net bags with chopped corn were buried in the central part (halfway between the top and bottom of the silo) of the bunkers (CCOR) in 3 sections 10 m apart. After filling, 18 net bags (9 per covering system) were buried 40 cm below the top surface of the 3 sections. These bags were placed at 3 distances from the bunker walls (0 to 50 cm, 51 to 100 cm, and 101 to 150 cm). During unloading, the bags were removed from the silos to determine the dry matter (DM) losses, fermentation end products, and nutritive value. The Milk2006 spreadsheet was used to estimate milk per tonne of DM. The model included the fixed effect of treatment (7 different locations in the bunker) and the random effect of the silo. Two contrasts were tested to compare silages in the top laterals (shoulders) with that in the CCOR (CCOR vs. OB and CCOR vs. ST). Three contrasts compared the corresponding distances of the silage covered by the 2 systems (OB50 vs. ST50, OB100 vs. ST100 and OB150 vs. ST150). Variables were analyzed with the PROC MIXED procedure of the SAS at the 5% level. The OB method produced well-fermented silages, which were similar to CCOR, whereas the OB system showed less lactic acid and greater pH and mold counts compared with CCOR. The ST method had 116.2 kg of milk/t less than the CCOR, as the OB system and the CCOR were similar

  18. Moisture Management for High R-Value Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R. [Building Science Corporation, Somerville, MA (United States); Schumacher, C. [Building Science Corporation, Somerville, MA (United States); Lukachko, A. [Building Science Corporation, Somerville, MA (United States)

    2013-11-01

    This report explains the moisture-related concerns for high R-value wall assemblies and discusses past Building America research work that informs this study. In this project, hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones. The modeling program assessed the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage; the report presents results of the study.

  19. Barrier penetration database

    International Nuclear Information System (INIS)

    Fainberg, A.; Bieber, A.M. Jr.

    1978-11-01

    This document is intended to supply the NRC and nuclear power plant licensees with basic data on the times required to penetrate forcibly the types of barriers commonly found in nuclear plants. These times are necessary for design and evaluation of the physical protection system required under 10CFR73.55. Each barrier listed is described in detail. Minor variations in basic barrier construction that result in the same penetration time, are also described

  20. Waterproofing with polymeric geo synthetic barriers (GBR-P) in the manual for the design, construction, management and maintenance of reservoirs

    International Nuclear Information System (INIS)

    Blanco, M.; Cea, J. C.; Garcia, F.; Sanchez, F. J.; Castillo, F.; Mora, J.; Crespo, M. A.

    2010-01-01

    This article presents a part of Manual for the Design, Construction, Management and Maintenance of Reservoirs relative to waterproofing with Polymeric Geo synthetic Barriers (GBR-P). the nature materials of geo membranes is studied also theirs characteristics and specifications. (Author) 26 refs.

  1. Permeable treatment wall design and cost analysis

    International Nuclear Information System (INIS)

    Manz, C.; Quinn, K.

    1997-01-01

    A permeable treatment wall utilizing the funnel and gate technology has been chosen as the final remedial solution for one industrial site, and is being considered at other contaminated sites, such as a closed municipal landfill. Reactive iron gates will be utilized for treatment of chlorinated VOCs identified in the groundwater. Alternatives for the final remedial solution at each site were evaluated to achieve site closure in the most cost effective manner. This paper presents the remedial alternatives and cost analyses for each site. Several options are available at most sites for the design of a permeable treatment wall. Our analysis demonstrates that the major cost factor's for this technology are the design concept, length, thickness, location and construction methods for the reactive wall. Minimizing the amount of iron by placement in the most effective area and construction by the lowest cost method is critical to achieving a low cost alternative. These costs dictate the design of a permeable treatment wall, including selection of a variety of alternatives (e.g., a continuous wall versus a funnel and gate system, fully penetrating gates versus partially penetrating gates, etc.). Selection of the appropriate construction methods and materials for the site can reduce the overall cost of the wall

  2. Ketamine alleviates bradykinin-induced disruption of the mouse cerebrovascular endothelial cell-constructed tight junction barrier via a calcium-mediated redistribution of occludin polymerization

    International Nuclear Information System (INIS)

    Chen, Jui-Tai; Lin, Yi-Ling; Chen, Ta-Liang; Tai, Yu-Ting; Chen, Cheng-Yu; Chen, Ruei-Ming

    2016-01-01

    Highlights: • Ketamine could suppress bradykinin-induced intracellular calcium mobilization. • Ketamine induced B1R protein and mRNA expressions but did not change B2R protein levels. • Ketamine attenuated bradykinin-induced redistribution of occludin tight junctions. • Ketamine prevented bradykinin-induced breakage of the MCEC-constructed tight junction barrier. - Abstract: Following brain injury, a sequence of mechanisms leads to disruption of the blood-brain barrier (BBB) and subsequent cerebral edema, which is thought to begin with activation of bradykinin. Our previous studies showed that ketamine, a widely used intravenous anesthetic agent, can suppress bradykinin-induced cell dysfunction. This study further aimed to evaluate the protective effects of ketamine against bradykinin-induced disruption of the mouse cerebrovascular endothelial cell (MCEC)-constructed tight junction barrier and the possible mechanisms. Exposure of MCECs to bradykinin increased intracellular calcium (Ca 2+ ) concentrations in a time-dependent manner. However, pretreatment of MCECs with ketamine time- and concentration-dependently lowered the bradykinin-induced calcium influx. As to the mechanisms, although exposure of MCECs to ketamine induced bradykinin R1 receptor protein and mRNA expression, this anesthetic did not change levels of the bradykinin R2 receptor, a major receptor that responds to bradykinin stimulation. Bradykinin increased amounts of soluble occludin in MCECs, but pretreatment with ketamine alleviated this disturbance in occludin polymerization. Consequently, exposure to bradykinin decreased the transendothelial electronic resistance in the MCEC-constructed tight junction barrier. However, pretreatment with ketamine attenuated the bradykinin-induced disruption of the tight junction barrier. Taken together, this study shows that ketamine at a therapeutic concentration can protect against bradykinin-induced breakage of the BBB via suppressing calcium

  3. Chemical barriers for controlling groundwater contamination

    International Nuclear Information System (INIS)

    Morrison, S.J.; Spangler, R.R.

    1993-01-01

    Chemical barriers are being explored as a low-cost means of controlling groundwater contamination. The barrier can intercept a contaminant plume and prevent migration by transferring contaminants from the groundwater to immobile solids. A chemical barrier can be emplaced in a landfill liner or in an aquifer cutoff wall or can be injected into a contaminant plume. Chemical barriers can be classified as either precipitation barriers or sorption barriers depending upon the dominant mode of contaminant extraction. In a precipitation barrier, contaminants are bound in the structures of newly formed phases; whereas, in a sorption barrier, contaminants attach to the surfaces of preexisting solids by adsorption or some other surface mechanism. Sorption of contaminants is pH dependent. A precipitation barrier can control the pH of the system, but alkaline groundwater may dominate the pH in a sorption barrier. A comparison is made of the characteristics of precipitation and sorption barriers. Experimental data on the extraction of uranium and molybdenum from simulated groundwater are used to demonstrate these concepts. 10 refs., 9 figs., 1 tab

  4. A review on the current issues and barriers of Industrialised Building System (IBS) adoption in Malaysia’s construction industry

    Science.gov (United States)

    Amin, M. A. Mohd; Abas, N. H.; Shahidan, S.; Rahmat, M. H.; Suhaini, N. A.; Nagapan, S.; Rahim, R. Abdul

    2017-11-01

    Malaysia considers the construction industry as one of the main contributors to its Gross Domestic Product (GDP). However, there are some unresolved issues arising from the ongoing and widespread adoption of the conventional method of construction such as the resultant fragmentation of the industry itself; delays in production and delivery time of unnecessary wastages and lack of sustainability practice. Malaysian Government has been continuously encouraging the industry to use, partly or if not wholly, the Industrialized Building System (IBS), which is considered to be an important part of sustainable construction initiative. IBS was introduced to Malaysia as the solution to issues related to dependencies of foreign workers, raising demand for affordable accommodations and improving image, quality and productivity of construction industry. However, the IBS adoption in Malaysia remains low. This paper presents the review of the current issues and barriers of IBS adoption in Malaysian construction industry.

  5. Isotope migration and barrier in a VLLW site

    International Nuclear Information System (INIS)

    Kang Houjun; Zhang Dong; Yang Yong; Shi Zhengkun; Li Kuanliang; Zhang Peicong

    2010-01-01

    In this work, adsorption and migration of 238 U and 90 Sr in unsaturated soil at a VLLW (very low level waste) site was investigated, in an attempt to find geochemical features of the site. Migration of the isotopes in heterosphere was studied under instantaneous and sequential conditions of the sources. The migration barrier experiment was carried out in two steps on wall rock absorption of the isotopes and addictives to improve the barrier of the wall rock to 90 Sr. The results show that the migration speed of 238 U and 90 Sr in the soil is 0.365 and 0.385 mm/a, respectively. The heterosphere effects on the isotope migration not only alleviated the mainstream contamination, but also prolonged the time of contaminated affection. And false zeolite should be used as barrier additive material for 90 Sr migration. (authors)

  6. Airtightness of the window-wall interface in masonry brick walls

    OpenAIRE

    Van Den Bossche, Nathan; Huyghe, Willem; Moens, Jan; Janssens, Arnold

    2013-01-01

    In recent decades there has been an increased focus on enhanced thermal resistance of building components and as a consequence, the relative importance of airtightness on the overall energy losses of buildings has increased significantly. The construction industry requires practical information on the airtightness of individual construction elements and building envelope interfaces. A literature review on the airtightness of window-wall interfaces has shown that no experimental data are avai...

  7. First wall thermal hydraulic models for fusion blankets

    International Nuclear Information System (INIS)

    Fillo, J.A.

    1980-01-01

    Subject to normal and off-normal reactor conditions, thermal hydraulic models of first walls, e.g., a thermal mass barrier, a tubular shield, and a radiating liner are reviewed. Under normal operation the plasma behaves as expected in a predicted way for transient and steady-state conditions. The most severe thermal loading on the first wall occurs when the plasma becomes unstable and dumps its energy on the wall in a very short period of time (milliseconds). Depending on the plasma dump time and area over which the energy is deposited may result in melting of the first wall surface, and if the temperature is high enough, vaporization

  8. Reciprocal Interactions between Cadmium-Induced Cell Wall Responses and Oxidative Stress in Plants

    Directory of Open Access Journals (Sweden)

    Christophe Loix

    2017-10-01

    Full Text Available Cadmium (Cd pollution renders many soils across the world unsuited or unsafe for food- or feed-orientated agriculture. The main mechanism of Cd phytotoxicity is the induction of oxidative stress, amongst others through the depletion of glutathione. Oxidative stress can damage lipids, proteins, and nucleic acids, leading to growth inhibition or even cell death. The plant cell has a variety of tools to defend itself against Cd stress. First and foremost, cell walls might prevent Cd from entering and damaging the protoplast. Both the primary and secondary cell wall have an array of defensive mechanisms that can be adapted to cope with Cd. Pectin, which contains most of the negative charges within the primary cell wall, can sequester Cd very effectively. In the secondary cell wall, lignification can serve to immobilize Cd and create a tougher barrier for entry. Changes in cell wall composition are, however, dependent on nutrients and conversely might affect their uptake. Additionally, the role of ascorbate (AsA as most important apoplastic antioxidant is of considerable interest, due to the fact that oxidative stress is a major mechanism underlying Cd toxicity, and that AsA biosynthesis shares several links with cell wall construction. In this review, modifications of the plant cell wall in response to Cd exposure are discussed. Focus lies on pectin in the primary cell wall, lignification in the secondary cell wall and the importance of AsA in the apoplast. Regarding lignification, we attempt to answer the question whether increased lignification is merely a consequence of Cd toxicity, or rather an elicited defense response. We propose a model for lignification as defense response, with a central role for hydrogen peroxide as substrate and signaling molecule.

  9. Barriers and post-closure monitoring (AL121125)

    International Nuclear Information System (INIS)

    Bostick, K.V.; Janecky, D.

    1995-01-01

    This project focuses on the rapid implementation of near-surface barriers, biotreatment, and post-closure monitoring technology. It uses water-permeable and biologic barriers that chemically capture and/or degrade contaminants without significantly altering the natural water flow regime. Barrier approaches are being tested for two different applications. The first is the use of barriers for confinement of chemical contaminants for in-trench treatments with leach systems or an in-place bioreactor. The second is an enhancement of the current practice of emplacing grout or clay slurry walls into direct horizontal surface and subsurface water flows around a contaminated area by integrating permeable reactive barriers and petroleum reservoir gel/foam/polymer technology

  10. Drywall plates evaluation as protection barriers in dental X-rays and mammography facilities

    International Nuclear Information System (INIS)

    Guevara R, V. Y.; Romero C, N.; Berrocal T, M.

    2014-08-01

    In the dental X-rays and mammography facilities, usually lead shielded walls as protective barriers are used. Lead is a good attenuator for X-rays, but has toxic properties and its cost is high. Mammography equipment s emit low-energy photons in the range of 25 keV to 35 keV, on current computers; the primary radiation beam is intercepted by the image receptor. Peri apical dental equipment s emit photons in the range of 50 to 90 keV, their filtration is fixed. These devices emit a collimated beam whose diameter is slightly larger than the diagonal dimension of a standard film of dental X-rays. When a dental x-ray is performed, the radiation beam is partially attenuated by the patient. Drywall is a material consisting of plasterboard between two cardboard layers, being its components gypsum and cellulose generally. It is used in construction for execution of interior walls, ceilings and wall coverings, could also serve as a replacement for lead as well as other materials. In this paper three drywall prototypes (Giplac), formed with 02, 04 and 06 drywall layers (13, 16 and 20 cm of thickness respectively) were tested as barriers against primary and secondary X-ray radiation that come from dental and mammography equipment s. The results show that the drywall prototype, 02 layers, efficiently attenuates the secondary radiation beam produced by conventional mammography equipment. And the prototype 04 and 06 layers, efficiently attenuates the primary radiation beam produced by peri apical dental equipment. (author)

  11. State-of-the-Art Review on Sustainable Design and Construction of Quieter Pavements—Part 1: Traffic Noise Measurement and Abatement Techniques

    Directory of Open Access Journals (Sweden)

    MD Ohiduzzaman

    2016-08-01

    Full Text Available Noise pollution due to highway traffic has drawn the attention of transportation agencies worldwide. Noise pollution is an irritant to residents, especially in urban areas near roads with high traffic volume. In addition to its adverse effects on the quality of life, traffic noise can induce stress that could lead to sleep disturbance and anxiety. Traditionally, noise barrier walls have been used for highways to mitigate traffic noise. However, using barrier walls as a noise abatement measure has proven to be very expensive. In addition to the cost, noise barrier walls are not always effective because they must break the line of sight to work properly, which is not always possible in case of intersections or driveways. Therefore, researchers especially from Europe and USA have been very proactive to reduce the noise at source. A number of research studies show traffic noise can be reduced by using an alternative surface type or changing texture of the pavement while complying with other requirements of sustainability, i.e., safety, structural durability, construction and maintenance costs. This paper presents a comprehensive review of the research conducted on this subject. A review of the tire-pavement noise generation and amplification mechanism, various traffic noise measurement methods and correlation among these methods, in addition to the abatement techniques used by various agencies to reduce pavement noise, is also presented.

  12. Solar Walls for concrete renovation

    DEFF Research Database (Denmark)

    Gramkow, Lotte; Vejen, Niels Kristian; Olsen, Lars

    1996-01-01

    This repport gives a short presentation of three full-scale testing solar walls, the construction including the architectural design, materials and components, transportation and storage of solar enegy, the effect on the construction behind, statics and practical experience.The results of the mea...

  13. Analysis on the construction technology of stone curtain wall in building engineering%关于建筑工程中石材幕墙施工工艺技术的探析

    Institute of Scientific and Technical Information of China (English)

    李苏慧

    2016-01-01

    This paper introduced the construction characteristics of stone curtain wall,from the positioning,lightning protection connection,stone panel installation,pendant installation and other aspects,elaborated the construction technology of stone curtain wall,and discussed the methods to improve the construction quality,conducive to promote the popularization and application of stone curtain wall.%介绍了石材幕墙的施工特点,从定位放线、防雷连接、石材面板安装、挂件安装等方面,阐述了石材幕墙的施工技术,以及提高其施工质量的方法,有利于促进石材幕墙的推广应用。

  14. Prototype Hanford Surface Barrier: Design basis document

    International Nuclear Information System (INIS)

    Myers, D.R.; Duranceau, D.A.

    1994-11-01

    The Hanford Site Surface Barrier Development Program (BDP) was organized in 1985 to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site and other arid sites. This document provides the basis of the prototype barrier. Engineers and scientists have momentarily frozen evolving barrier designs and incorporated the latest findings from BDP tasks. The design and construction of the prototype barrier has required that all of the various components of the barrier be brought together into an integrated system. This integration is particularly important because some of the components of the protective barreir have been developed independently of other barreir components. This document serves as the baseline by which future modifications or other barrier designs can be compared. Also, this document contains the minutes of meeting convened during the definitive design process in which critical decisions affecting the prototype barrier's design were made and the construction drawings

  15. Confirmation tests of construction method and initial performance quality for low permeable engineered barrier in side part of radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Yamada, Atsuo; Chijimatsu, Masakazu; Akiyama, Yoshihiro; Komine, Hideo; Iizuka, Atsushi

    2016-01-01

    As for the low permeable layer, important functions are expected as an engineered barrier of radioactive waste disposal for low-level waste with comparatively high radiation levels. On examining the construction methods of this low permeable layer, it is important to confirm the possibility of the construction in the conditions similar to the actual constructed conditions with a true scale size. Therefore, the construction examination for the side part of the low permeable layer by bentonite and the performance check test of the low permeable layer were carried out. The result of the construction examination showed that the possibility of the construction were confirmed, and the result of performance check test showed that it was possible to ensure the required performance of the low permeable layer, such as hydraulic conductivity. (author)

  16. SU-E-T-267: Construction and Evaluation of a Neutron Wall to Shield a 15 MV Linac in a Low-Energy Vault.

    Science.gov (United States)

    Speiser, M; Hager, F; Foster, R; Solberg, T

    2012-06-01

    To design and quantify the shielding efficacy of an inner Borated Polyethylene (BPE)wall for a 15 MV linac in a low energy vault. A Varian TrueBeam linac with a maximum photon energy of 15 MV was installed in asmaller, preexisting vault. This vault originally housed a low-energy machine and did not havesufficient maze length recommended for neutron attenuation. Effective dose rate calculationswere performed using the Modified Kersey's Method as detailed in NCRP Report No. 151 andfound to be unacceptably high. An initial survey following the machine installation confirmedthese calculations. Rather than restrict the linac beam energy to 10 MV, BPE was investigatedas a neutron moderating addition. An inner wall and door were planned and constructed using4'×8'×1″ thick 5% BPE sheets. The resulting door and wall had 2″ of BPE; conduits and ductwork were also redesigned and shielded. A survey was conducted following construction of thewall. The vault modification reduced the expected effective dose at the vault door from 36.23to 0.010 mSv/week. As specific guidelines for vault modification are lacking, this project quantitativelydemonstrates the potential use of BPE for vault modification. Such modifications may provide alow-cost shielding solution to allow for the use of high energy modes in smaller treatment vaults. © 2012 American Association of Physicists in Medicine.

  17. Designing a Sound Reducing Wall

    Science.gov (United States)

    Erk, Kendra; Lumkes, John; Shambach, Jill; Braile, Larry; Brickler, Anne; Matthys, Anna

    2015-01-01

    Acoustical engineers use their knowledge of sound to design quiet environments (e.g., classrooms and libraries) as well as to design environments that are supposed to be loud (e.g., concert halls and football stadiums). They also design sound barriers, such as the walls along busy roadways that decrease the traffic noise heard by people in…

  18. Delays in nuclear power plant construction. Volume II. Final report

    International Nuclear Information System (INIS)

    Mason, G.E.; Larew, R.E.; Borcherding, J.D.; Okes, S.R. Jr.; Rad, P.F.

    1977-01-01

    The report identifies barriers to shortening nuclear power plant construction schedules and recommends research efforts which should minimize or eliminate the identified barriers. The identified barriers include (1) Design and Construction Interfacing Problems; (2) Problems Relating to the Selection and Use of Permanent Materials and Construction Methods; (3) Construction Coordination and Communication Problems; and (4) Problems Associated with Manpower Availability and Productivity

  19. Delays in nuclear power plant construction. Volume I. Final report

    International Nuclear Information System (INIS)

    1977-01-01

    The report identifies barriers to shortening nuclear power plant construction schedules and recommends research efforts which should minimize or eliminate the identified barriers. The identified barriers include: (1) Design and Construction Interfacing Problems; (2) Problems Relating to the Selection and Use of Permanent Materials and Construction Methods; (3) Construction Coordination and Communication Problems; and (4) Problems Associated with Manpower Availability and Productivity

  20. Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs.

    Science.gov (United States)

    Hahner, J; Hoyer, M; Hillig, S; Schulze-Tanzil, G; Meyer, M; Schröpfer, M; Lohan, A; Garbe, L-A; Heinrich, G; Breier, A

    2015-01-01

    A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

  1. Construction of a self-supporting tissue-equivalent dividing wall and operational characteristics of a coaxial double-cylindrical tissue-equivalent proportional counter

    International Nuclear Information System (INIS)

    Saion, E.B.; Watt, D.E.

    1994-01-01

    An additional feature incorporated in a coaxial double-cylindrical tissue-equivalent proportional counter, is the presence of a common tissue-equivalent dividing wall between the inner and outer counters of thickness equivalent to the corresponding maximum range of protons at the energy of interest. By appropriate use of an anti-coincidence arrangement with the outer counter, the inner counter could be used to discriminate microdosimetric spectra of neutrons at the desired low energy range from those of the faster neutrons. The construction of an A-150 self-supporting tissue-equivalent dividing wall and an anti-coincidence unit are described. Some operational characteristic tests have been performed to determine the operation of the new microdosimeter. (author)

  2. Shielding walls against ionizing radiation. Lead bricks

    International Nuclear Information System (INIS)

    1993-04-01

    The standard contains specifications for the shape and requirements set for lead bricks such that they can be used to construct radiation-shielding walls according to the building kit system. The dimensions of the bricks are selected in such a way as to permit any modification of the length, height and thickness of said shielding walls in units of 50 mm. The narrow side of the lead bricks juxtaposed to one another in a wall construction to shield against radiation have to form prismatic grooves and tongues: in this way, direct penetration by radiation is prevented. Only cuboid bricks (serial nos. 55-60 according to Table 10) do not have prismatic tongues and grooves. (orig.) [de

  3. Bridging the divide: Middle Eastern walls and fences and the spatial governance of problem populations

    NARCIS (Netherlands)

    Pallister-Wilkins, P.

    2015-01-01

    Building on a long history of spatial control through walling in the region, walls and fences have been built in the Middle East in recent years to undertake a range of practices. Gated communities, residential and security compounds, anti-migrant walls, separation barriers and counter-insurgency

  4. Formation of three-dimensional cell/polymer constructs for bone tissue engineering in a spinner flask and a rotating wall vessel bioreactor

    Science.gov (United States)

    Sikavitsas, Vassilios I.; Bancroft, Gregory N.; Mikos, Antonios G.; McIntire, L. V. (Principal Investigator)

    2002-01-01

    The aim of this study is to investigate the effect of the cell culture conditions of three-dimensional polymer scaffolds seeded with rat marrow stromal cells (MSCs) cultured in different bioreactors concerning the ability of these cells to proliferate, differentiate towards the osteoblastic lineage, and generate mineralized extracellular matrix. MSCs harvested from male Sprague-Dawley rats were culture expanded, seeded on three-dimensional porous 75:25 poly(D,L-lactic-co-glycolic acid) biodegradable scaffolds, and cultured for 21 days under static conditions or in two model bioreactors (a spinner flask and a rotating wall vessel) that enhance mixing of the media and provide better nutrient transport to the seeded cells. The spinner flask culture demonstrated a 60% enhanced proliferation at the end of the first week when compared to static culture. On day 14, all cell/polymer constructs exhibited their maximum alkaline phosphatase activity (AP). Cell/polymer constructs cultured in the spinner flask had 2.4 times higher AP activity than constructs cultured under static conditions on day 14. The total osteocalcin (OC) secretion in the spinner flask culture was 3.5 times higher than the static culture, with a peak OC secretion occurring on day 18. No considerable AP activity and OC secretion were detected in the rotating wall vessel culture throughout the 21-day culture period. The spinner flask culture had the highest calcium content at day 14. On day 21, the calcium deposition in the spinner flask culture was 6.6 times higher than the static cultured constructs and over 30 times higher than the rotating wall vessel culture. Histological sections showed concentration of cells and mineralization at the exterior of the foams at day 21. This phenomenon may arise from the potential existence of nutrient concentration gradients at the interior of the scaffolds. The better mixing provided in the spinner flask, external to the outer surface of the scaffolds, may explain the

  5. The Cell Wall of Bacillus subtilis

    NARCIS (Netherlands)

    Scheffers, Dirk-Jan; Graumann, Peter

    2012-01-01

    The cell wall of Bacillus subtilis is a rigid structure on the outside of the cell that forms the first barrier between the bacterium and the environment, and at the same time maintains cell shape and withstands the pressure generated by the cell’s turgor. In this chapter, the chemical composition

  6. In situ stabilization wall for containment and hot spot retrieval

    International Nuclear Information System (INIS)

    Loomis, G.G.

    1996-01-01

    This paper presents the results of a full scale field demonstration of a in situ stabilization technology applicable to buried transuranic waste. The technology involves creating a jet grouted wall around selected regions or hot spots within a buried waste site. The resulting wall provides a barrier against further horizontal migration of the contaminants and allows vertical digging of material inside the wall, thus minimizing waste during a hot spot removal action. The demonstration involved creating a open-quotes Uclose quotes shaped wall in the interior of a full sized, simulated waste pit. The wall simulated the main features of a four sided wall. The demonstration also involved a destructive examination and a stability test for a hot spot retrieval scenario

  7. Design of barrier coatings on kink-resistant peripheral nerve conduits

    Directory of Open Access Journals (Sweden)

    Basak Acan Clements

    2016-02-01

    Full Text Available Here, we report on the design of braided peripheral nerve conduits with barrier coatings. Braiding of extruded polymer fibers generates nerve conduits with excellent mechanical properties, high flexibility, and significant kink-resistance. However, braiding also results in variable levels of porosity in the conduit wall, which can lead to the infiltration of fibrous tissue into the interior of the conduit. This problem can be controlled by the application of secondary barrier coatings. Using a critical size defect in a rat sciatic nerve model, the importance of controlling the porosity of the nerve conduit walls was explored. Braided conduits without barrier coatings allowed cellular infiltration that limited nerve recovery. Several types of secondary barrier coatings were tested in animal studies, including (1 electrospinning a layer of polymer fibers onto the surface of the conduit and (2 coating the conduit with a cross-linked hyaluronic acid-based hydrogel. Sixteen weeks after implantation, hyaluronic acid-coated conduits had higher axonal density, displayed higher muscle weight, and better electrophysiological signal recovery than uncoated conduits or conduits having an electrospun layer of polymer fibers. This study indicates that braiding is a promising method of fabrication to improve the mechanical properties of peripheral nerve conduits and demonstrates the need to control the porosity of the conduit wall to optimize functional nerve recovery.

  8. Evolution of the Stability Work from Classic Retaining Walls to Mechanically Stabilized Earth Walls

    Directory of Open Access Journals (Sweden)

    Anghel Stanciu

    2008-01-01

    Full Text Available For the consolidation of soil mass and the construction of the stability works for roads infrastructure it was studied the evolution of these kinds of works from classical retaining walls - common concrete retaining walls, to the utilization in our days of the modern and competitive methods - mechanically stabilized earth walls. Like type of execution the variety of the reinforced soil is given by the utilization of different types of reinforcing inclusions (steel strips, geosynthetics, geogrids or facing (precast concrete panels, dry cast modular blocks, metal sheets and plates, gabions, and wrapped sheets of geosynthetics.

  9. Between the street and the wall: the construction of an interface in gated communities

    Directory of Open Access Journals (Sweden)

    Karin Schwabe Meneguetti

    2016-07-01

    Full Text Available Streets are fundamental open spaces to urban life and their landscape is conditioned by the occupation form and use of lots along it. However, recent urbanization processes have shown changes in the relationship between public and private spaces. Among these changes are the large gated communities within the urban fabric. They result in high and continuous walls, which reject the interface with the neighboring streets, thus negatively affecting urban environment quality. This paper aims to present a possibility to construct the interface between gated communities and outside streets. An experience of gated communities surrounded by multi-purpose lots built in the city of Maringá, Brazil, will be reported. The application of this typomorphology in several of these real estate enterprise has demonstrated significant improvement in the quality of the street landscape.

  10. Considering the use of polyethylene vapour barriers in temperate climates

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, M.D. [Morrison Hershfield Ltd., Vancouver, BC (Canada); Brown, W.C. [Morrison Hershfield Ltd., Ottawa, ON (Canada)

    2003-07-01

    Most building envelope assemblies in Canada must include a vapour barrier in order to comply with Canadian building codes. The installation of sheet polyethylene between the studs and the interior sheathing has been the most common method because it provides more diffusion resistance than necessary to control condensation within a building envelope assembly. It has been suggested that the presence of a polyethylene vapour barrier on the warm-in-winter side of the insulation may actually cause moisture problems because a very low permeance material increases average moisture levels. This paper examined the theory that a vapour barrier at this location restricts drying of moisture that enters the building from outside. Pacific coastal regions of Canada and the United States were presented as examples. Other ways that a polyethylene vapour barrier affects wall performance were also presented. The advanced hygrothermal model HygIRC, developed by Canada's National Research Council, was used to simulate the performance of a wall assembly. Results indicate that eliminating the low permeance polyethylene vapour barrier does not necessarily reduce the risk of moisture problems. Removal of the vapour barrier may have some negative effects, such as increased risk of periodic moisture accumulation and mold growth on paper-faced gypsum board. 7 refs., 2 tabs., 7 figs.

  11. 49 CFR 587.17 - Construction.

    Science.gov (United States)

    2010-10-01

    ... Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.17 Construction... in), 700 mm (27.5 in), 900 mm (35.4 in) horizontally, from either edge of the barrier. All holes are...

  12. Institutional Motivations and Barriers to the Construction of Green Buildings on Campus: A Case Study of the University of Waterloo, Ontario

    Science.gov (United States)

    Richardson, Gregory R. A.; Lynes, Jennifer K.

    2007-01-01

    Purpose: To explore the barriers and motivations to the construction of green buildings at the University of Waterloo (UW) by documenting and analysing the UW building process. Design/methodology/approach: The authors conducted 13 semi-structured in-depth interviews with key UW individuals as well as analyzing numerous internal reports in order to…

  13. Revision of Sustainable Criteria of Concrete Walls for Earthquake-Resistant Housing

    Directory of Open Access Journals (Sweden)

    Alcocer S.M.

    2012-10-01

    Full Text Available The seismic performance of low-rise housing has been noticeably inadequate during the most recent earthquakes occurred in Latin American countries. Moreover, the literature review revealed that some traditional techniques do not contribute to building sustainable housing. In the last decade, construction of concrete walls housing has become a preferred choice because of the speed of construction and availability of materials in most of these countries. Aimed at improving seismic design methods for this type of construction, an extensive analytical and experimental program was carried out. The experimental program included quasi-static and shaking-table tests of 47 walls with different height-to-length ratios and walls with openings. Variables studied were type of concrete, web steel ratio and type of web reinforcement. The paper presents and discusses the main results of the research program and evaluates the technical and environmental feasibility for using concrete walls for sustainable and earthquake-resistant housing. Performance of concrete walls housing is assessed in terms of key environmental and earthquake-resistant requirements. It was found that concrete wall housing is not only safe under earthquakes and easily adaptable to climate, but also it stimulates environmental conservation and promotes reducing the costs of construction, operation and maintenance.

  14. Structure of steel reactor building and construction method therefor

    International Nuclear Information System (INIS)

    Yamakawa, Toshikimi.

    1997-01-01

    The building of the present invention contains a reactor pressure vessel, and has double steel plate walls endurable to elevation of inner pressure and keeping airtightness, and shielding concretes are filled between the double steel plate walls. It also has empty double steel plate walls not filled with concretes and has pipelines, vent ducts, wirings and a support structures for attaching them between the double steel plate walls. It is endurable to a great inner pressure satisfactory and keeps airtightness by the two spaced steel plates. It can be greatly reduced in the weight, and can be manufactured efficiently with high quality in a plant by so called module construction, and the dimension of the entire of the reactor building can be reduced. It is constructed in a dock, transported on the sea while having the space between the two steel plate walls as a ballast tanks, placed in the site, and shielding concretes are filled between the double steel plate walls. The term for the construction can be reduced, and the cost for the construction can be saved. (N.H.)

  15. Flooding Effect on Earth Walls

    Directory of Open Access Journals (Sweden)

    Meysam Banimahd

    2010-12-01

    Full Text Available Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.

  16. General Corrosion and Localized Corrosion of Waste Package Outer Barrier

    Energy Technology Data Exchange (ETDEWEB)

    K.G. Mon

    2004-10-01

    The waste package design for the License Application is a double-wall waste package underneath a protective drip shield (BSC 2004 [DIRS 168489]; BSC 2004 [DIRS 169480]). The purpose and scope of this model report is to document models for general and localized corrosion of the waste package outer barrier (WPOB) to be used in evaluating waste package performance. The WPOB is constructed of Alloy 22 (UNS N06022), a highly corrosion-resistant nickel-based alloy. The inner vessel of the waste package is constructed of Stainless Steel Type 316 (UNS S31600). Before it fails, the Alloy 22 WPOB protects the Stainless Steel Type 316 inner vessel from exposure to the external environment and any significant degradation. The Stainless Steel Type 316 inner vessel provides structural stability to the thinner Alloy 22 WPOB. Although the waste package inner vessel would also provide some performance for waste containment and potentially decrease the rate of radionuclide transport after WPOB breach before it fails, the potential performance of the inner vessel is far less than that of the more corrosion-resistant Alloy 22 WPOB. For this reason, the corrosion performance of the waste package inner vessel is conservatively ignored in this report and the total system performance assessment for the license application (TSPA-LA). Treatment of seismic and igneous events and their consequences on waste package outer barrier performance are not specifically discussed in this report, although the general and localized corrosion models developed in this report are suitable for use in these scenarios. The localized corrosion processes considered in this report are pitting corrosion and crevice corrosion. Stress corrosion cracking is discussed in ''Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material'' (BSC 2004 [DIRS 169985]).

  17. BARRIER MARKET RESTRICTIONS, THEIR ECONOMIC NATURE AND CONSEQUENCES

    Directory of Open Access Journals (Sweden)

    Maksimova Ekaterina Yurievna

    2018-02-01

    Full Text Available Subject: indicators of modern economic growth in construction, published by the government agencies, reflect individual directions of growth. At the same time, the analysis of the reasons for the unachieved results is conducted by various researchers primarily from the standpoint of the inadequacy of economic and other resources. This article deals with the problem of ensuring the growth of construction enterprises from the viewpoint of systemic barriers, and in this regard, these barriers are defined as the subject of the present research. Research objectives: studying the concept of barrier market restrictions, their impact on the activities of construction companies. Materials and methods: statistical data in the field of housing construction, provided by the Ministry of Construction of the Russian Federation and Rosstat, is examined to solve the given tasks set. The content of state programs and activities of state institutions in the field of support and development of construction activities is considered. Based on investigations of sustainable economic development, an understanding of the constraints and incentives for development is revealed. Results: we have identified the content of barrier market restrictions, which are not possible to overcome only by involving additional economic resources in the turnover. The ways of confronting these restrictions are shown. Conclusions: it was shown that implementation of promising activities is impossible without overcoming various systemic constraints. Their structure is described in sufficient detail. Principles of economic sustainable development are proposed. It was proved that the reserve system can serve as an effective way to overcome market barriers.

  18. Laboratory studies and model simulations of sorbent material behavior for an in-situ passive treatment barrier

    International Nuclear Information System (INIS)

    Aloysius, D.; Fuhrmann, M.

    1995-01-01

    This paper presents a study combining laboratory experiments and model simulations in support of the design and construction of a passive treatment barrier (or filter wall) for retarding the migration of Sr-90 within a water-bearing surficial sand and gravel layer. Preliminary evaluation was used to select materials for column testing. A one-dimensional finite-difference model was used to simulate the laboratory column results and extrapolation of the calibrated model was then used to assess barrier performance over extended time frames with respect to Sr-90 breakthrough and loading on the filter media. The final results of the study showed that 20 by 50 mesh clinoptilolite will attenuate Sr-90 with a maximum life expentancy of approximately 10 years. This time period is based on allowable limits of Sr-90 activity on the filter media and is also a function of site-specific conditions

  19. Hanford Site Long-term Surface Barrier Development Program: Fiscal year 1994 highlights

    International Nuclear Information System (INIS)

    Petersen, K.L.; Link, S.O.; Gee, G.W.

    1995-08-01

    The Hanford Site Surface Barrier Development Program was organized in 1985 to test the effectiveness of various barrier designs in minimizing the effects of water infiltration; plant, animal and human intrusion; and wind and water erosion on buried wastes, plus preventing or minimizing the emanation of noxious gases. A team of scientists from the Pacific Northwest Laboratory (PNL) and engineers from Westinghouse Hanford Company (WHC) direct the barrier development effort. ICF Kaiser Hanford Company, in conjunction with WHC and PNL, developed design drawings and construction specifications for a 5-acre prototype barrier. The highlight of efforts in FY 1994 was the construction of the prototype barrier. The prototype barrier was constructed on the Hanford Site at the 200 BP-1 Operable Unit of the 200 East Area. Construction was completed in August 1994 and monitoring instruments are being installed so experiments on the prototype barrier can begin in FY 1995. The purpose of the prototype barrier is to provide insights and experience with issues regarding barrier design, construction, and performance that have not been possible with individual tests and experiments conducted to date. Additional knowledge and experience was gained in FY 1994 on erosion control, physical stability, water infiltration control, model testing, Resource Conservation and Recovery Act (RCRA) comparisons, biointrusion control, long-term performance, and technology transfer

  20. Developing Key Parameters for Green Performance of Partition Wall Blocks

    Directory of Open Access Journals (Sweden)

    Goh Cheng Siew

    2016-01-01

    Full Text Available To promote sustainable construction, it is important to consider green performance of construction materials throughout the life cycle. Selecting inappropriate materials could not only affect the functional performance but also preclude the achievement of green building performance as a whole. Green performance of construction materials has therefore been one of the primary considerations of green building assessment systems. Using partition wall blocks as an example, this paper examines green performance of building materials primarily from the cradle to gate boundaries. Nine key parameters are proposed for the green performance of partition wall blocks. Apart from environmental features, technical performance of partition wall blocks is also taken into consideration since it is the determinant of the lifecycle performance. This paper offers a roadmap to decision makers to make environmentally responsible choices for their materials of internal walls and partitions, and hence provides a potential sustainable solution for green buildings.

  1. Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers

    International Nuclear Information System (INIS)

    Pinson, Paul Arthur

    1998-01-01

    Safety and reliability in glovebox operations can be significantly improved and waste packaging efficiencies can be increased by inserting flexible, lightweight, high capacity HEPA filters into the walls of plastic sheet barriers. This HEPA filter/barrier technology can be adapted to a wide variety of applications: disposable waste bags, protective environmental barriers for electronic equipment, single or multiple use glovebag assemblies, flexible glovebox wall elements, and room partitions. These reliable and inexpensive filtered barriers have many uses in fields such as radioactive waste processing, HVAC filter changeout, vapor or grit blasting, asbestos cleanup, pharmaceutical, medical, biological, and electronic equipment containment. The applications can result in significant cost savings, improved operational reliability and safety, and total waste volume reduction. This technology was developed at the Argonne National Laboratory-West (ANL-W) in 1993 and has been used at ANL-W since then at the TRU Waste Characterization Chamber Gloveboxes. Another 1998 AGS Conference paper titled ''TRU Waste Characterization Gloveboxes'', presented by Mr. David Duncan of ANL-W, describes these boxes

  2. Moisture Management for High R-Value Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R.; Schumacher, C.; Lukachko, A.

    2013-11-01

    The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.

  3. Hygrothermal behavior for a clay brick wall

    Science.gov (United States)

    Allam, R.; Issaadi, N.; Belarbi, R.; El-Meligy, M.; Altahrany, A.

    2018-06-01

    In Egypt, the clay brick is the common building materials which are used. By studying clay brick walls behavior for the heat and moisture transfer, the efficient use of the clay brick can be reached. So, this research studies the hygrothermal transfer in this material by measuring the hygrothermal properties and performing experimental tests for a constructed clay brick wall. We present the model for the hygrothermal transfer in the clay brick which takes the temperature and the vapor pressure as driving potentials. In addition, this research compares the presented model with previous models. By constructing the clay brick wall between two climates chambers with different boundary conditions, we can validate the numerical model and analyze the hygrothermal transfer in the wall. The temperature and relative humidity profiles within the material are measured experimentally and determined numerically. The numerical and experimental results have a good convergence with 3.5% difference. The surface boundary conditions, the ground effect, the infiltration from the closed chambers and the material heterogeneity affects the results. Thermal transfer of the clay brick walls reaches the steady state very rapidly than the moisture transfer. That means the effect of using only the external brick wall in the building in hot climate without increase the thermal resistance for the wall, will add more energy losses in the clay brick walls buildings. Also, the behavior of the wall at the heat and mass transfer calls the three-dimensional analysis for the whole building to reach the real behavior.

  4. Hygrothermal behavior for a clay brick wall

    Science.gov (United States)

    Allam, R.; Issaadi, N.; Belarbi, R.; El-Meligy, M.; Altahrany, A.

    2018-01-01

    In Egypt, the clay brick is the common building materials which are used. By studying clay brick walls behavior for the heat and moisture transfer, the efficient use of the clay brick can be reached. So, this research studies the hygrothermal transfer in this material by measuring the hygrothermal properties and performing experimental tests for a constructed clay brick wall. We present the model for the hygrothermal transfer in the clay brick which takes the temperature and the vapor pressure as driving potentials. In addition, this research compares the presented model with previous models. By constructing the clay brick wall between two climates chambers with different boundary conditions, we can validate the numerical model and analyze the hygrothermal transfer in the wall. The temperature and relative humidity profiles within the material are measured experimentally and determined numerically. The numerical and experimental results have a good convergence with 3.5% difference. The surface boundary conditions, the ground effect, the infiltration from the closed chambers and the material heterogeneity affects the results. Thermal transfer of the clay brick walls reaches the steady state very rapidly than the moisture transfer. That means the effect of using only the external brick wall in the building in hot climate without increase the thermal resistance for the wall, will add more energy losses in the clay brick walls buildings. Also, the behavior of the wall at the heat and mass transfer calls the three-dimensional analysis for the whole building to reach the real behavior.

  5. Jet grouting for a groundwater cutoff wall in difficult glacial soil deposits

    International Nuclear Information System (INIS)

    Flanagan, R.F.; Pepe, F. Jr.

    1997-01-01

    Jet grouting is being used as part of a groundwater cutoff wall system in a major New York City subway construction project to limit drawdowns in an adjacent PCB contamination plume. A circular test shaft of jet grout columns was conducted during the design phase to obtain wall installation parameters. The test program also included shaft wall mapping, and measurements of; inflows, piezometric levels, ground heave and temperature, and jet grout hydraulic conductivity. An axisymmetric finite element method groundwater model was established to back calculate the in-situ hydraulic conductivities of both the surrounding glacial soils and the jet grout walls by matching observed inflows and piezometric levels. The model also verified the use of packer permeability test as a tool in the field to evaluate the hydraulic conductivities of jet grout columns. Both the test program and analytic studies indicated that adjustments to the construction procedures would be required to obtain lower hydraulic conductivities of the jet grout walls for construction. A comparison is made with the conductivities estimated from the test program/analytic studies with those from the present construction

  6. Decorating multi-walled carbon nanotubes with quantum dots for construction of multi-color fluorescent nanoprobes

    International Nuclear Information System (INIS)

    Jia Nengqin; Lian Qiong; Tian Zhong; Yin Min; Che, Shouhui; Shen Hebai; Duan Xin; Jing Lihong; Gao Mingyuan

    2010-01-01

    Novel multi-color fluorescent nanoprobes were prepared by electrostatically assembling differently sized CdTe quantum dots on polyethylenimine (PEI) functionalized multi-walled carbon nanotubes (MWNTs). The structural and optical properties of the nano-assemblies (MWNTs-PEI-CdTe) were characterized by transmission electron microscopy (TEM), electron diffraction spectra (EDS), Raman spectroscopy, confocal microscopy and photoluminescence spectroscopy (PL), respectively. Electrochemical impedance spectroscopy (EIS) was also applied to investigate the electrostatic assembling among oxidized MWNTs, PEI and CdTe. Furthermore, confocal fluorescence microscopy was used to monitor the nano-assemblies' delivery into tumor cells. It was found that the nano-assemblies exhibit efficient intracellular transporting and strong intracellular tracking. These properties would make this luminescent nano-assembly an excellent building block for the construction of intracellular nanoprobes, which could hold great promise for biomedical applications.

  7. Containment technology at the 'Griftpark' former MGP site in the Netherlands

    International Nuclear Information System (INIS)

    Vries, P.W. de; Viveen, B.

    1997-01-01

    'Griftpark' is a former highly contaminated gasworks site of approximately 8 hectares situated in Utrecht (The Netherlands). The MGP site is contained by a vertical barrier wall made of a specific mixture of bentonite-concrete and underlying clay layers at depths of 50 to 60 m which are slowly permeable. The barrier wall is 80 cm thick, has an average depth of 64 m, a length of 1260 m and has a total surface area of approximately 70,000 m 2 . The construction of the barrier wall took nearly three years, from 1993 to 1995, to complete and building costs approximated 35 million US$ whereas the total project costs amounted to more than 150 million US$ including water detoxification. Migration of contaminants in the soil strata is successfully arrested by the construction of the barrier wall which was built conform NEN-ISO 9000/9001 standards. Wall permeability which was tested during a ten months period after construction demonstrates fully warranted reliability. This year a top layer will be installed consisting of an open insolation without foil. After placement of the top the site will be developed into a recreation park. Contaminant migration will permanently be monitored

  8. Statistical analysis of silo wall pressures

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Berntsen, Kasper Nikolaj

    1998-01-01

    Previously published silo wall pressure measurements during plug flow of barley in alarge concrete silo are re-analysed under the hypothesis that the wall pressures are gamma-distributed.The fits of the gamma distribution type to the local pressure data from each measuring cell are satisfactory.......However, the estimated parameters of the gamma distributions turn out to be significantly inhomogeneous overthe silo wall surface. This inhomogeneity is attributed to the geometrical imperfections of the silo wall.Motivated by the engineering importance of the problem a mathematical model for constructing astochastic...... gamma-type continuous pressure field is given. The model obeys the necessary equilibrium conditionsof the wall pressure field and reflects the spatial correlation properties as estimated from simultaneouslymeasured pressures at different locations along a horizontal perimeter....

  9. Feasibility of permeation grouting for constructing subsurface barriers

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1994-04-01

    Efforts are being made to devise technologies that provide interim containment of waste sites while final remediation alternatives are developed. Permeation grouting, a technique used extensively in the civil and mining engineering industry has been investigated as a method for emplacing a subsurface containment barrier beneath existing waste sites. Conceptually an underlying barrier is placed by injecting grout into the formation at less than fracturing pressure from a series of directionally drilled boreholes beneath the waste site. This study evaluated the penetration and performance characteristics in varying soil conditions of four different grout materials (two microfine cements, mineral wax, and sodium silicate) at a field scale. Field testing consisted of grout injection via sleeve (tube-a'-manchette) pipe into both vertical and horizontal borehole configurations at the Mixed Waste Landfill Integrated Demonstration site at Sandia National Laboratories. Prior to, during, and after grout injection non-intrusive geophysical techniques were used to map grout flow. Following the tests, the site was excavated to reveal details of the grout permeation, and grouted soil samples were cored for laboratory characterization. The non-intrusive and intrusive grout mapping showed preferential flow patterns, i.e., the grout tended to follow the path of least resistance. Preliminary testing indicates that permeation grouting is a feasible method for emplacing a low permeability subsurface barrier in the semi-arid unconsolidated alluvial soils common to the Southwest. Despite the success of this project, difficulties in predicting grout flow in heterogeneous soils and non-intrusive methods for imaging grout location and continuity are issues that need more attention

  10. Project and construction of a spectrometer for alpha particles using surface barrier detectors

    International Nuclear Information System (INIS)

    Terini, R.A.

    1986-01-01

    The project, construction, tests and some applications of a system for alpha and beta spectrometry, using surface barrier detector are described. The device includes a solid state detector ORTEC-Series F coupled to a system for amplifying the charges produced by passage of an ionizing particle through the detector. The amplifying system is composed by a charge sensitive pre-amplifier, which employs an operational amplifier CA 3140, and a low noise linear amplifier, which is based on the operational amplifiers CA 3140 and LM 301. The pre-amplifier stage input impedance is on the order of TΩ and produces output pulses which heights are proportional to total charge produced by passage of particle through the detector sensitive volume. The main advantage to use charge sensitive system lies in obtention of independent pulse heights of the distributed capacity of connecting cable between the detector and the pre-amplifier. The total system amplification ca reach a maximum of 50.000 in the linear region. Pulses are analysed in a multichannel system ORTEC, model 6240. The amplifier system is easily constructed and low cost using components available in the national market, and it can be employed with ionization chambers, proportional counters, scitillation counters and semiconductor detectors. The results of spectrometer application for alpha spectrometry of AM 241 source were compared to systems made with imported stages. (Author) [pt

  11. Advanced Extended Plate and Beam Wall System in a Cold-Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, Dave [Partnership for Home Innovation, Upper Marlboro, MD (United States); Wiehagen, Joseph [Partnership for Home Innovation, Upper Marlboro, MD (United States); Kochkin, Vladimir [Partnership for Home Innovation, Upper Marlboro, MD (United States)

    2016-01-01

    This report presents the design and evaluation of an innovative wall system. This highly insulated (high-R) light-frame wall system for use above grade in residential buildings is referred to as Extended Plate & Beam (EP&B). The EP&B design is the first of its kind to be featured in a new construction test house (NCTH) for the DOE Building America program. The EP&B wall design integrates standard building methods and common building products to construct a high-R wall that minimizes transition risks and costs to builders.

  12. Ancient engineering geology projects in China; A canal system in Ganzu province and trenches along the Great Wall in Ningxia Hui Autonomous Region

    Science.gov (United States)

    Wallace, R.E.; Bucknam, R.C.; Hanks, T.C.

    1994-01-01

    Two major construction projects of ancient times in China involved what today would be considered engineering geology. We describe an ancient canal system in Gaotai County, Gansu province that was possibly begun in the Han dynasty (206 BC-220 AD). The canal system heads at the Dasha River and extends northwestward for about 55 km to the City of Camels and Xusanwan village. Four parallel canals are present at the local site we examined. The canals were likely built primarily to transport water but may also have served as defensive military barriers. A second project involves trenches and berms along the north side of the Great Wall, clearly part of the Great Wall defensive system. This site is in Ningxia Autonomous Region near the town of Shizuishan. ?? 1994.

  13. Enzymatic cell wall degradation of high-pressure-homogenized tomato puree and its effect on lycopene bioaccessibility.

    Science.gov (United States)

    Palmero, Paola; Colle, Ines; Lemmens, Lien; Panozzo, Agnese; Nguyen, Tuyen Thi My; Hendrickx, Marc; Van Loey, Ann

    2016-01-15

    High-pressure homogenization disrupts cell structures, assisting carotenoid release from the matrix and subsequent micellarization. However, lycopene bioaccessibility of tomato puree upon high-pressure homogenization is limited by the formation of a process-induced barrier. In this context, cell wall-degrading enzymes were applied to hydrolyze the formed barrier and enhance lycopene bioaccessibility. The effectiveness of the enzymes in degrading their corresponding substrates was evaluated (consistency, amount of reducing sugars, molar mass distribution and immunolabeling). An in vitro digestion procedure was applied to evaluate the effect of the enzymatic treatments on lycopene bioaccessibility. Enzymatic treatments with pectinases and cellulase were proved to effectively degrade their corresponding cell wall polymers; however, no further significant increase in lycopene bioaccessibility was obtained. A process-induced barrier consisting of cell wall material is not the only factor governing lycopene bioaccessibility upon high-pressure homogenization. © 2015 Society of Chemical Industry.

  14. 多向可调节柔性连接式石材幕墙施工技术%Multi Direction Adjustable Connection Stone Curtain Wall Construction Technology

    Institute of Scientific and Technical Information of China (English)

    杨军

    2016-01-01

    This paper introduces a new type of surface stone curtain wall construction technology, the technology used to adjust the flexible back bolt of the multi direction can be adjusted, improved the construction efficiency of special⁃shaped curved surface stone, irregular curved surface stone curtain wall facade effect can be better.%介绍了一种新的异形曲面石材幕墙施工技术,该技术运用多向可调节柔性背栓的多向可调节性,提高了异形曲面石材的施工效率,异形曲面石材幕墙的外立面效果得以更好呈现。

  15. The Role of Pectin Acetylation in the Organization of Plant Cell Walls

    DEFF Research Database (Denmark)

    Fimognari, Lorenzo

    adopt defined 3D organization to allow their composition/interactions to be tweaked upon developmental need. Failure to build functional cell wall architecture will affect plant growth and resistance to stresses. In this PhD dissertation I explored the role of pectin acetylation in controlling...... wall organization, namely polysaccharides-to-polysaccharides interactions. These results suggest that cell wall acetylation is a mechanism that plants evolved to control cell wall organization. In Manuscript III, we report the characterization of Arabidopsis mutants trichome birefringence like (tbl) 10......All plant cells are surrounded by one or more cell wall layers. The cell wall serves as a stiff mechanical support while it allows cells to expand and provide a protective barrier to invading pathogens. Cell walls are dynamic structures composed of entangled cell wall polysaccharides that must...

  16. The Backscattering of Gamma Radiation from Plane Concrete Walls

    Energy Technology Data Exchange (ETDEWEB)

    Leimdoerfer, M

    1962-12-15

    Monte Carlo calculations have been performed for source energies from 1 to 10 MeV, and normally incident radiation, showing that 90 % of the infinite-barrier energy flux albedo is reached with a 40 cm concrete wall. The spectrum of backscattered energy flux is presented for the above sources and wall thicknesses ranging from 5 to 50 cm, An analytical expression, based on a single-scattering approximation, is shown to produce good fits to the Monte Carlo results.

  17. Converse Theorems for Safety and Barrier Certificates

    OpenAIRE

    Ratschan, Stefan

    2017-01-01

    An important tool for proving safety of dynamical systems is the notion of a barrier certificate. In this paper we prove that every robustly safe ordinary differential equation has a barrier certificate. Moreover, we show a construction of such a barrier certificate based on a set of states that is reachable in finite time.

  18. The Unfolded Protein Response Is Induced by the Cell Wall Integrity Mitogen-activated Protein Kinase Signaling Cascade and Is Required for Cell Wall Integrity in Saccharomyces cerevisiae

    OpenAIRE

    Scrimale, Thomas; Didone, Louis; de Mesy Bentley, Karen L.; Krysan, Damian J.

    2009-01-01

    The yeast cell wall is an extracellular structure that is dependent on secretory and membrane proteins for its construction. We investigated the role of protein quality control mechanisms in cell wall integrity and found that the unfolded protein response (UPR) and, to a lesser extent, endoplasmic reticulum (ER)-associated degradation (ERAD) pathways are required for proper cell wall construction. Null mutation of IRE1, double mutation of ERAD components (hrd1Δ and ubc7Δ) and ire1Δ, or expres...

  19. Electrical resisitivity of mechancially stablized earth wall backfill

    Science.gov (United States)

    Snapp, Michael; Tucker-Kulesza, Stacey; Koehn, Weston

    2017-06-01

    Mechanically stabilized earth (MSE) retaining walls utilized in transportation projects are typically backfilled with coarse aggregate. One of the current testing procedures to select backfill material for construction of MSE walls is the American Association of State Highway and Transportation Officials standard T 288: ;Standard Method of Test for Determining Minimum Laboratory Soil Resistivity.; T 288 is designed to test a soil sample's electrical resistivity which correlates to its corrosive potential. The test is run on soil material passing the No. 10 sieve and believed to be inappropriate for coarse aggregate. Therefore, researchers have proposed new methods to measure the electrical resistivity of coarse aggregate samples in the laboratory. There is a need to verify that the proposed methods yield results representative of the in situ conditions; however, no in situ measurement of the electrical resistivity of MSE wall backfill is established. Electrical resistivity tomography (ERT) provides a two-dimensional (2D) profile of the bulk resistivity of backfill material in situ. The objective of this study was to characterize bulk resistivity of in-place MSE wall backfill aggregate using ERT. Five MSE walls were tested via ERT to determine the bulk resistivity of the backfill. Three of the walls were reinforced with polymeric geogrid, one wall was reinforced with metallic strips, and one wall was a gravity retaining wall with no reinforcement. Variability of the measured resistivity distribution within the backfill may be a result of non-uniform particle sizes, thoroughness of compaction, and the presence of water. A quantitative post processing algorithm was developed to calculate mean bulk resistivity of in-situ backfill. Recommendations of the study were that the ERT data be used to verify proposed testing methods for coarse aggregate that are designed to yield data representative of in situ conditions. A preliminary analysis suggests that ERT may be utilized

  20. Use of reinforced soil wall to support steam generator transfer

    International Nuclear Information System (INIS)

    Davie, J.R.; Wang, J.T.; Gladstone, R.A.

    1991-01-01

    Consumers Power Company had the two steam generators at its Palisades Nuclear Plant in Michigan replaced in November 1990. This replacement was accomplished through a 26-foot wide by 28-foot high opening cut into the wall of the containment building, about 45 feet above the original ground surface. Because this ground surface was at an approximately 3-H:1-V slope, leveling was required before replacement in order to provide access for the steam generators and adequate support for the heavy-duty gantry crane system used to transfer the generators. A 25-foot high reinforced soil wall was constructed to achieve the level surface. This paper describes the design and construction of the heavily loaded reinforced soil wall, including ground improvement measures required to obtain adequate wall stability. The performance of the wall under test loading will also be presented and discussed

  1. Preliminary engineering specifications for a test demonstration multilayer protective barrier cover system

    International Nuclear Information System (INIS)

    Phillips, S.J.; Gilbert, T.W.; Adams, M.R.

    1985-03-01

    This report presents preliminary engineering specifications for a test protective barrier cover system and support radiohydrology facility to be constructed at the Hanford Protective Barrier Test Facility (PBTF). Construction of this test barrier and related radiohydrology facility is part of a continuing effort to provide construction experience and performance evaluation of alternative barrier designs used for long-term isolation of disposed radioactive waste materials. Design specifications given in this report are tentative, based on interim engineering and computer simulation design efforts. Final definitive design specifications and engineering prints will be produced in FY 1986. 6 refs., 10 figs., 1 tab

  2. High Performance Walls in Hot-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Springer, David [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Dakin, Bill [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); German, Alea [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2015-01-01

    High performance walls represent a high priority measure for moving the next generation of new homes to the Zero Net Energy performance level. The primary goal in improving wall thermal performance revolves around increasing the wall framing from 2x4 to 2x6, adding more cavity and exterior rigid insulation, achieving insulation installation criteria meeting ENERGY STAR's thermal bypass checklist. To support this activity, in 2013 the Pacific Gas & Electric Company initiated a project with Davis Energy Group (lead for the Building America team, Alliance for Residential Building Innovation) to solicit builder involvement in California to participate in field demonstrations of high performance wall systems. Builders were given incentives and design support in exchange for providing site access for construction observation, cost information, and builder survey feedback. Information from the project was designed to feed into the 2016 Title 24 process, but also to serve as an initial mechanism to engage builders in more high performance construction strategies. This Building America project utilized information collected in the California project.

  3. Arabidopsis Regenerating Protoplast: A Powerful Model System for Combining the Proteomics of Cell Wall Proteins and the Visualization of Cell Wall Dynamics

    Science.gov (United States)

    Yokoyama, Ryusuke; Kuki, Hiroaki; Kuroha, Takeshi; Nishitani, Kazuhiko

    2016-01-01

    The development of a range of sub-proteomic approaches to the plant cell wall has identified many of the cell wall proteins. However, it remains difficult to elucidate the precise biological role of each protein and the cell wall dynamics driven by their actions. The plant protoplast provides an excellent means not only for characterizing cell wall proteins, but also for visualizing the dynamics of cell wall regeneration, during which cell wall proteins are secreted. It therefore offers a unique opportunity to investigate the de novo construction process of the cell wall. This review deals with sub-proteomic approaches to the plant cell wall through the use of protoplasts, a methodology that will provide the basis for further exploration of cell wall proteins and cell wall dynamics. PMID:28248244

  4. Interaction of tide and salinity barrier: Limitation of numerical model

    Directory of Open Access Journals (Sweden)

    Suphat Vongvisessomjai1

    2008-07-01

    Full Text Available Nowadays, the study of interaction of the tide and the salinity barrier in an estuarine area is usually accomplished vianumerical modeling, due to the speed and convenience of modern computers. However, numerical models provide littleinsight with respect to the fundamental physical mechanisms involved. In this study, it is found that all existing numericalmodels work satisfactorily when the barrier is located at some distance far from upstream and downstream boundary conditions.Results are considerably underestimate reality when the barrier is located near the downstream boundary, usually theriver mouth. Meanwhile, this analytical model provides satisfactory output for all scenarios. The main problem of thenumerical model is that the effects of barrier construction in creation of reflected tide are neglected when specifying thedownstream boundary conditions; the use of the boundary condition before construction of the barrier which are significantlydifferent from those after the barrier construction would result in an error outputs. Future numerical models shouldattempt to account for this deficiency; otherwise, using this analytical model is another choice.

  5. The in-situ vitrification of subsurface containment barriers: An overview

    International Nuclear Information System (INIS)

    Murphy, M.; Stottlemyre, J.A.

    1990-11-01

    In situ vitrification (ISV) is an environmental engineering process in which soil or soil/waste mixtures are melted through the direct application of electrical current and subsequently cooled to a glassy solid. The technology was developed by Pacific Northwest Laboratory (PNL) in the 1980s and has been tested on transuranic, mixed-hazardous, and PCB/organic waste similar to that found at US Department of Energy (DOE) and other facilities nationwide. PNL is conducting a wide range of field tests, expanding the scientific basis of ISV, and assessing its extension into new applications. One such project is ISV--Selective Barriers, an investigation into the construction and performance of ISV--generated, vertical and/or horizontal subsurface barriers to ground-water flow and biogenic intrusion. In some situations, it may be impractical or unnecessary to either excavate or vitrify an entire waste site. Vitrified barriers could minimize the diffusive or fluid transport of hazardous components with either a ground-water diversion wall or an in situ, ''box-like'' structure. During the first year of this project, engineering-scale tests are being conducted between graphite electrodes within a 1.8-m-diameter, 2.4-m-high test cell. Several methods are being tested, including passive metal electrodes, electrode feeding systems, fluxed soil, and fluxed boreholes. In addition, basic data have been collected on the thermal and material properties of ISV melt and solidified glass. 7 refs., 6 figs

  6. Stress dependence of the domain wall potential in amorphous CoFeSiB glass-coated microwires

    International Nuclear Information System (INIS)

    Varga, R.; Zhukov, A.; Blanco, J.M.; Gonzalez, J.; Zhukova, V.; Vojtanik, P.

    2006-01-01

    We present a method to study the domain wall potential through the thermal activation of the domain wall across the energy barrier. Two contributions to the domain wall potential in amorphous microwires are recognized: magnetoelastic and relaxation. The role of each contribution is studied by measuring the switching field distribution at different frequencies and under applied stress

  7. Investigation of interior post-insulated masonry walls with wooden beam ends

    DEFF Research Database (Denmark)

    Morelli, Martin; Svendsen, Svend

    2013-01-01

    The preponderant number of multistorey buildings constructed in Denmark in the period between 1850 and 1930 were built with masonry walls incorporating wooden floor beams. Given the nature of this construction, it is supposed that significant energy savings could be achieved by simply insulating...... the facades of such buildings. To maintain the exterior appearance of the facade, the only possible means of installing the required insulation is placing it on the interior of the wall. However, the installation of insulation on the interior of the wall assembly reduces the overall drying potential...

  8. Activity measurements of radon from construction materials.

    Science.gov (United States)

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Investigation on Wall Panel Sandwiched With Lightweight Concrete

    Science.gov (United States)

    Lakshmikandhan, K. N.; Harshavardhan, B. S.; Prabakar, J.; Saibabu, S.

    2017-08-01

    The rapid population growth and urbanization have made a massive demand for the shelter and construction materials. Masonry walls are the major component in the housing sector and it has brittle characteristics and exhibit poor performance against the uncertain loads. Further, the structure requires heavier sections for carrying the dead weight of masonry walls. The present investigations are carried out to develop a simple, lightweight and cost effective technology for replacing the existing wall systems. The lightweight concrete is developed for the construction of sandwich wall panel. The EPS (Expanded Polystyrene) beads of 3 mm diameter size are mixed with concrete and developed a lightweight concrete with a density 9 kN/m3. The lightweight sandwich panel is cast with a lightweight concrete inner core and ferrocement outer skins. This lightweight wall panel is tested for in-plane compression loading. A nonlinear finite element analysis with damaged plasticity model is carried out with both material and geometrical nonlinearities. The experimental and analytical results were compared. The finite element study predicted the ultimate load carrying capacity of the sandwich panel with reasonable accuracy. The present study showed that the lightweight concrete is well suitable for the lightweight sandwich wall panels.

  10. Construction materials and Radon

    International Nuclear Information System (INIS)

    Paschuk, Sergei A.; Correa, Janine Nicolosi; Loriane, Fior; Schelin, Hugo R.; Pottker, Fabiana; Paula Melo, Vicente de

    2008-01-01

    Full text: Current studies have been performed with the aim to find the correlation of radon concentration in the air and used construction materials. At the first stage of the measurements different samples of materials used in civil construction were studied as a source of radon in the air and at the second step it was studied the radon infiltration insulation using different samples of finishing materials. For 222 Rn concentration measurements related to different construction materials as well as for the studies of radon emanation and its reduction, the sealed cell chambers, of approximately 60 x 60cm 2 , have been built using the ceramic and concrete blocks. This construction has been performed within protected and isolated laboratory environment to maintain the air humidity and temperature stable. These long term measurements have been performed using polycarbonate alpha track passive detectors. The exposure time was set about 15 days considering previous calibration performed at the Institute of Radiation Protection and Dosimetry (IRD/CNEN), where the efficiency of 70% was obtained for the density of alpha particle tracks about 13.8 cm -2 per exposure day and per kBq/m 3 of radon activity concentration. The chemical development of alpha tracks has been achieved by electrochemical etching. The track identification and counting have been done using a code based on the MATLAB Image Processing Toolbox. The cell chambers have been built following four principle steps: 1) Assembling the walls using the blocks and mortar; 2) Plaster installation; 3) Wall surface finishing using the lime; 4) Wall surface insulation by paint. Making the comparison between three layers installed at the masonry walls from concrete and ceramic blocks, it could be concluded that only wall painting with acrylic varnish attended the expectation and reduced the radon emanation flow by the factor of 2.5 approximately. Studied construction materials have been submitted the instant

  11. A Method of Assembling Wall or Floor Elements

    DEFF Research Database (Denmark)

    2002-01-01

    The invention relates to a method of constructing, at the site of use, a building wall (1) or a building floor (1) using a plurality of prefabricated concrete or lightweight concrete plate-shaped wall of floor elements (10), in particular cast elements, which have a front side and a rear side...

  12. Design and construction of earth retaining walls with anchors employed in excavation works at Oi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Saino, Susumu; Aoshima, Ken-ichiro; Kamide, Atsushi.

    1990-01-01

    In Oi Nuclear Power Station, Kansai Electric Power Co., Inc., No.3 and No.4 plants of each 1180 MWe output are additionally installed, neighboring existing No.1 and No.2 plants of each 1175 MWe output in operation. The start of operation is expected in December, 1991 in No.3 plant, and in February, 1993 in No.4 plant. The total quantity of earth excavated for this additional installation works is about 3.3 million m 3 . The main works are, subsequently to the preparation of the site, the excavation for the foundations of reactor buildings and others, and the construction of the foundations for the seawater system facilities for cooling condensers and reactor auxiliary machines, and the works were begun in May, 1987. The excavation by using anchors was carried out in seven places. The vertical excavation on large scale was carried out by using the earth retaining walls of concrete-sprayed anchor structure in drain pits. In this report, the outline of the geological features, the outline of the excavation works, the design of the earth retaining walls, the execution of concrete spraying, the planning and result of measurement are described. (K.I.)

  13. New-construction techniques and HVAC overpressurization for radon reduction in schools

    International Nuclear Information System (INIS)

    Saum, D.; Witter, K.A.; Craig, A.B.

    1988-01-01

    Construction of a school in Fairfax County, Virginia, is being carefully monitored since elevated indoor radon levels have been identified in many existing houses near the site. Soil gas radon concentrations measured prior to pouring of the slabs were also indicative of a potential radon problem should the soil gas enter the school; however, subslab radon measurements collected thus far are lower than anticipated. Radon-resistant features have been incorporated into construction of the school and include the placing of at least 100 mm of clean coarse aggregate under the slab and a plastic film barrier between the aggregate and the slab, the sealing of all expansion joints, the sealing or plugging of all utility penetrations where possible, and the painting of interior block walls. In addition, the school's heating, ventilating, and air-conditioning (HVAC) system has been designed to operate continuously in overpressurization to help reduce pressure-driven entry of radon-containing soil gas into the building. Following completion, indoor radon levels in the school will be monitored to determine the effectiveness of these radon-resistant new-construction techniques and HVAC overpressurization in limiting radon entry into the school

  14. Contaminant fluxes through site containment barriers: Performance assessment and illustrative results

    International Nuclear Information System (INIS)

    Vita, C.L.

    1994-01-01

    Contaminant mass flux by advective and diffusive transport is predicted for five containment barriers that use one or more clay liners, flexible membrane liners (FMLs), or liquid collection and removal systems (LCRS)s. Barriers are engineered systems intended to contain and isolate site contaminants from the environment. Barriers include liners, caps, and cutoff walls. Barriers may be used in contaminated-site cleanups (including CERCLA and RCRA), RCRA landfills, or other RCRA TSDFs. Concepts are provided for barrier performance assessment, including analysis and optimization, for meeting performance requirements and controlling risk at minimum cost. Concepts and results can help in planning, designing, or evaluating and communicating, the use or effectiveness of proposed or existing barriers for site cleanups or waste containment. 15 refs., 6 figs., 5 tabs

  15. Novel targeted approach to better understand how natural structural barriers govern carotenoid in vitro bioaccessibility in vegetable-based systems.

    Science.gov (United States)

    Palmero, Paola; Lemmens, Lien; Ribas-Agustí, Albert; Sosa, Carola; Met, Kristof; de Dieu Umutoni, Jean; Hendrickx, Marc; Van Loey, Ann

    2013-12-01

    An experimental approach, allowing us to understand the effect of natural structural barriers (cell walls, chromoplast substructures) on carotenoid bioaccessibility, was developed. Different fractions with different levels of carotenoid bio-encapsulation (carotenoid-enriched oil, chromoplasts, small cell clusters, and large cell clusters) were isolated from different types of carrots and tomatoes. An in vitro method was used to determine carotenoid bioaccessibility. In the present work, a significant decrease in carotenoid in vitro bioaccessibility could be observed with an increasing level of bio-encapsulation. Differences in cell wall material and chromoplast substructure between matrices influenced carotenoid release and inclusion in micelles. For carrots, cell walls and chromoplast substructure were important barriers for carotenoid bioaccessibility while, in tomatoes, the chromoplast substructure represented the most important barrier governing bioaccessibility. The highest increase in carotenoid bioaccessibility, for all matrices, was obtained after transferring carotenoids into the oil phase, a system lacking cell walls and chromoplast substructures that could hamper carotenoid release. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Israel's Security Barrier: Effects On Operational Factors

    National Research Council Canada - National Science Library

    2004-01-01

    .... The route of the barrier is tinder intense discussion at this time and if implemented as planned by the Sharon government will negatively affect the factors of space and force. The barrier must be constructed along the correct route in order to maximize operational factors.

  17. Interaction between drilled shaft and mechanically stabilized earth (MSE) wall : project summary.

    Science.gov (United States)

    2015-08-31

    Drilled shafts are being constructed within the reinforced zone of mechanically stabilized earth (MSE) walls (Figure 1). The drilled shafts may be subjected to horizontal loads and push against the front of the wall. Distress of MSE wall panels has b...

  18. A seismic analysis for masonry constructions: The different schematization methods of masonry walls

    Science.gov (United States)

    Olivito, Renato. S.; Codispoti, Rosamaria; Scuro, Carmelo

    2017-11-01

    Seismic analysis of masonry structures is usually analyzed through the use of structural calculation software based on equivalent frames method or to macro-elements method. In these approaches, the masonry walls are divided into vertical elements, masonry walls, and horizontal elements, so-called spandrel elements, interconnected by rigid nodes. The aim of this work is to make a critical comparison between different schematization methods of masonry wall underlining the structural importance of the spandrel elements. In order to implement the methods, two different structural calculation software were used and an existing masonry building has been examined.

  19. Environmental life cycle assessment of permeable reactive barriers: effects of construction methods, reactive materials and groundwater constituents.

    Science.gov (United States)

    Mak, Mark S H; Lo, Irene M C

    2011-12-01

    The effects of the construction methods, materials of reactive media and groundwater constituents on the environmental impacts of a permeable reactive barrier (PRB) were evaluated using life cycle assessment (LCA). The PRB is assumed to be installed at a simulated site contaminated by either Cr(VI) alone or Cr(VI) and As(V). Results show that the trench-based construction method can reduce the environmental impacts of the remediation remarkably compared to the caisson-based method due to less construction material consumption by the funnel. Compared to using the zerovalent iron (Fe(0)) and quartz sand mixture, the use of the Fe(0) and iron oxide-coated sand (IOCS) mixture can reduce the environmental impacts. In the presence of natural organic matter (NOM) in groundwater, the environmental impacts generated by the reactive media were significantly increased because of the higher usage of Fe(0). The environmental impacts are lower by using the Fe(0) and IOCS mixture in the groundwater with NOM, compared with using the Fe(0) and quartz sand mixture. Since IOCS can enhance the removal efficiency of Cr(VI) and As(V), the usage of the Fe(0) can be reduced, which in turn reduces the impacts induced by the reactive media.

  20. New home construction: Eric Allen

    Energy Technology Data Exchange (ETDEWEB)

    1987-02-01

    This report describes some special energy efficient measures incorporated in the construction of a modestly-priced two and a half storey frame house with a floor area of 108 m{sup 2}. The house was built facing south, on a south-sloping lot with a thick stand of Jack Pine on the north side. The major energy efficient measures are: continuous air-vapour barrier and high insulation level to make the house as air-tight as possible; the use of passive solar heat which is expected to supply 37% of the annual heating requirements; a crawlspace plenum which draws hot air from the top of the house and recirculates it under the first floor; and use of horizontal strapping on which all wall partitions, electrical and plumbing work was done in order not to break the continuous air-vapour barrier and which itself provides extra insulation. The cost of making the house energy efficient was $2,500. The price of the house on completion was projected to be $65,000. The cost for the energy efficiency measures is 4% of the total. The Allen house is a good example of how an investment of a small percentage of the total cost, and about 67 hours of work, can result in an energy efficient house. The resulting savings on energy bills can be quite significant and can mean a return on the investment within 5 years. 3 figs., 1 tab.

  1. Delays in nuclear power plant construction. Progress report, September 15, 1976--September 14, 1977

    International Nuclear Information System (INIS)

    Mason, G.E.; Larew, R.E.

    1977-01-01

    This report identifies barriers to shortening nuclear power plant construction schedules and recommends research efforts that should minimize or eliminate the identified barriers. The identified barriers include: (1) design and construction interfacing problems; (2) problems relating to the selection and use of permanent materials and construction methods; (3) construction coordination and communication problems; and (4) problems associated with manpower availability and productivity;

  2. Determination of attenuation properties of massive ceramic bricks cladded with mortars containing barite used as protective barrier for radiodiagnostic rooms

    International Nuclear Information System (INIS)

    Barros, Frieda S.; Schelin, Hugo R.; Tilly Junior, Joao G.; Costa, Paulo R.; Nersissian, Denise Y.; Pereira, Marco A.G.

    2001-01-01

    The purpose of this work is to determine the properties of attenuation of the walls built with massive ceramic bricks to be used as protection barriers in environments of Medicine and Dentistry, when submitted to X-ray diagnosis. Massive ceramic bricks are used thoroughly in constructions as a calking element. The properties of attenuation of these materials were obtained starting from the application of the model of Archer to a group of attenuation curves with wide beams generated in the tensions of 70, 80, 100, 120, 140 and 150 kVp. A radiological equipment of constant potential was used in the Laboratory of IEE/USP, two cameras of ionization of 6cm 3 , coupled to two radiation monitors. The results show that for a tension of 100kVp, the thickness of 10cm of wall made with massive ceramic bricks corresponds to 1mm of lead. (author)

  3. Strengthening of Unreinforced Masonry Walls with Composite Materials

    Directory of Open Access Journals (Sweden)

    Ioana-Sorina Enţuc

    2004-01-01

    Full Text Available Unreinforced masonry (URM is considered one of the oldest construction materials being until the end of XIXth century, the basic material for: foundations, walls, columns, volts, staircases, floor joints, roofs, retaining walls, drainage channels, barrages, etc. Construction with URM elements posses a series of advantages such as: fire resistance, thermal an acoustic insulations between interior and outside spaces, humidity resistance. However the URM elements have some significant inconveniences such as: large self weight (heaviness causes cracks in the other elements of structures, reduced mechanical strengths in comparison with other traditional materials (steel and concrete, low tenacity, great manual labor consumptions, and vulnerability to earthquakes. Various factors cause deteriorations which must be overcome by strengthening solutions. Some strengthening solutions based on fiber reinforced polymers (FRP products applied directly on URM brick walls are presented in the paper.

  4. Hanford protoype surface barrier status report: FY 1994

    International Nuclear Information System (INIS)

    Gee, G.W.; Freeman, H.D.; Walters, W.H. Jr.; Ligotke, M.W.; Campbell, M.D.; Ward, A.L.; Link, S.O.; Smith, S.K.; Gilmore, B.G.; Romine, R.A.

    1994-12-01

    A full-scale prototype surface barrier has been constructed at the 200 BP-1 Operable Unit in the 200 East Area of the Hanford Site. The prototype barrier has been built to evaluate design, construction, and performance features of a surface barrier that may be used for in-place disposal of wastes at the Hanford Site. The design basis and construction of the prototype have been documented. A testing and monitoring plan has been published outlining specific tests planned for the prototype. The current report describes initial testing activities conducted in FY 1994 and outlines activities for testing and monitoring at the prototype barrier in the future. Asphalt permeability was tested during construction of the prototype in April and May 1994. Cores taken from the asphalt concrete layer were tested in the laboratory and found to have hydraulic conductivities below 1E-09 cm/s. Field measurements of hydraulic conductivity taken on the asphalt concrete using a specially-designed falling head permeameter were more than ten times higher than those from core tests. The higher values are attributed to transient flow through the permeameter seal. In spite of this difficulty, the more rapid field measurements (1-day tests in the field compared to 3 months in the laboratory) gave values as low as IE-09 cm/s and averaged about IE-08 cm/s. Samples of fluid-applied asphalt material, used as a sealant on the asphalt concrete layer, were. tested in the laboratory and found to have hydraulic conductivities below IE-10 cm/s. Measurements of hydraulic conductivity taken on an adjacent asphalt test pad using a sealed double-ring infiltrometer (SDRI) were initiated in September 1994 and are expected to be completed in November 1994. Construction of the prototype surface barrier was completed in August 1994

  5. Study on vibration behaviors of engineered barrier system

    International Nuclear Information System (INIS)

    Mikoshiba, Tadashi; Ogawa, Nobuyuki; Minowa, Chikahiro

    1998-01-01

    High-level radioactive wastes have been buried underground by packing into a strong sealed container made from carbon steel (over-pack) with buffer material (bentonite). The engineered barrier system constructed with an overpack and buffer materials must be resistant to earthquakes as well as invasion of groundwater for a long period. Therefore, seismic evaluation of barrier system for earthquakes is indispensable especially in Japan to keep its structural safety. Here, the effects of earthquake vibration on the engineered barrier systems were investigated experimentally. Random-wave vibration and practical seismic wave one were loaded for the systems and fundamental data were obtained. For the former vibration the response characteristics of both engineered barrier models constructed with overpack and bentonite were non-linear. For the latter one, the stress in bentonite was increased in proportion to the vibration level. (M.N.)

  6. [Study on Hollow Brick Wall's Surface Temperature with Infrared Thermal Imaging Method].

    Science.gov (United States)

    Tang, Ming-fang; Yin, Yi-hua

    2015-05-01

    To address the characteristic of uneven surface temperature of hollow brick wall, the present research adopts soft wares of both ThermaCAM P20 and ThermaCAM Reporter to test the application of infrared thermal image technique in measuring surface temperature of hollow brick wall, and further analyzes the thermal characteristics of hollow brick wall, and building material's impact on surface temperature distribution including hollow brick, masonry mortar, and so on. The research selects the construction site of a three-story-high residential, carries out the heat transfer experiment, and further examines the exterior wall constructed by 3 different hollow bricks including sintering shale hollow brick, masonry mortar and brick masonry. Infrared thermal image maps are collected, including 3 kinds of sintering shale hollow brick walls under indoor heating in winter; and temperature data of wall surface, and uniformity and frequency distribution are also collected for comparative analysis between 2 hollow bricks and 2 kinds of mortar masonry. The results show that improving heat preservation of hollow brick aid masonry mortar can effectively improve inner wall surface temperature and indoor thermal environment; non-uniformity of surface temperature decreases from 0. 6 to 0. 4 °C , and surface temperature frequency distribution changes from the asymmetric distribution into a normal distribution under the condition that energy-saving sintering shale hollow brick wall is constructed by thermal mortar replacing cement mortar masonry; frequency of average temperature increases as uniformity of surface temperature increases. This research provides a certain basis for promotion and optimization of hollow brick wall's thermal function.

  7. The dorsal shell wall structure of Mesozoic ammonoids

    Directory of Open Access Journals (Sweden)

    Gregor Radtke

    2017-03-01

    Full Text Available The study of pristine preserved shells of Mesozoic Ammonoidea shows different types of construction and formation of the dorsal shell wall. We observe three major types: (i The vast majority of Ammonoidea, usually planispirally coiled, has a prismatic reduced dorsal shell wall which consists of an outer organic component (e.g., wrinkle layer, which is the first layer to be formed, and the subsequently formed dorsal inner prismatic layer. The dorsal mantle tissue suppresses the formation of the outer prismatic layer and nacreous layer. With the exception of the outer organic component, secretion of a shell wall is omitted at the aperture. A prismatic reduced dorsal shell wall is always secreted immediately after the hatching during early teleoconch formation. Due to its broad distribution in (planispiral Ammonoidea, the prismatic reduced dorsal shell wall is probably the general state. (ii Some planispirally coiled Ammonoidea have a nacreous reduced dorsal shell wall which consists of three mineralized layers: two prismatic layers (primary and secondary dorsal inner prismatic layer and an enclosed nacreous layer (secondary dorsal nacreous layer. The dorsal shell wall is omitted at the aperture and was secreted in the rear living chamber. Its layers are a continuation of an umbilical shell doubling (reinforcement by additional shell layers that extends towards the ventral crest of the preceding whorl. The nacreous reduced dorsal shell wall is formed in the process of ontogeny following a prismatic reduced dorsal shell wall. (iii Heteromorph and some planispirally coiled taxa secrete a complete dorsal shell wall which forms a continuation of the ventral and lateral shell layers. It is formed during ontogeny following a prismatic reduced dorsal shell wall or a priori. The construction is identical with the ventral and lateral shell wall, including a dorsal nacreous layer. The wide distribution of the ability to form dorsal nacre indicates that it is

  8. Hanford prototype-barrier status report: FY 1995

    International Nuclear Information System (INIS)

    Gee, G.W.; Ward, A.L.; Gilmore, B.G.; Ligotke, M.W.; Link, S.O.

    1995-11-01

    Surface barriers (or covers) have been proposed for use at the Hanford Site as a means to isolate certain waste sites that, for reasons of cost or worker safety or both, may not be exhumed. Surface barriers are intende to isolated the wastes from the accessible environment and to provide long-term protection to future populations that might use the Hanford Site. Currently, no ''proven'' long-term barrier system is available. For this reason, the Hanford Site Permanent Isolation Surface-Barrier Development Program (BDP) was organized to develop the technology needed to provide long-term surface barrier capability for the Hanford Site for the US Department of Energy (DOE). Designs have been proposed to meet the most stringent needs for long-term waste disposal. The objective of the current barrier design is to use natural materials to develop a protective barrier system that isolates wastes for at least 1000 years by limiting water, plant, animal, and human intrusion; and minimizing erosion. The design criteria for water drainage has been set at 0.5 mm/yr. While other design criteria are more qualitative, it is clear that waste isolation for an extended time is the prime objective of the design. Constructibility and performance. are issues that can be tested and dealt with by evaluating prototype designs prior to extensive construction and deployment of covers for waste sites at Hanford

  9. The Berlin Wall: A Simulation for the Social Studies Classroom

    Science.gov (United States)

    Russell, William B., III

    2010-01-01

    November 9, 2009, marked the twentieth anniversary of the opening of the Berlin Wall. The Wall, a symbol of the Cold War, separated the German people for 28 years (1961-1989), keeping those on the East side isolated. Although the construction and dismantling of the Berlin Wall is a significant part of history, the topic is little covered in the…

  10. Geophysical characterization of subsurface barriers

    International Nuclear Information System (INIS)

    Borns, D.J.

    1995-08-01

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier

  11. Investigation of microclimate between wall and furniture with CFD

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Woloszyn, Monika; Rode, Carsten

    2005-01-01

    velocities and diffusion transport in constructions is presented. It is a CFD model where the air is modelled as a mixture of dry air and water vapour and walls fluids modelled with ordinary wall characteristics as material properties. This enables easy modelling of moisture transfer within the walls....... This investigation has special focus on the coupling of the moisture transfers in the wall and the moisture content of the air. The microclimate in a room is studied for different geometrical configurations, meaning that the moisture and temperature conditions are analysed and discussed using different distances...

  12. Sustainable development and construction industry in Malaysia

    Directory of Open Access Journals (Sweden)

    Suliman L. Kh. M.

    2009-12-01

    Full Text Available Sustainable construction is a way for the building and infrastructure industry to move towards achieving sustainable development, taking into account environmental, socioeconomic and cultural issues. Differing approaches and differing economic markets lead to different priorities. This paper presents the construction scenario of Malaysia and the developments in sustainable construction taking place in this country. Barriers to the implementation of sustainable construction are discussed. A list of recommendation was proposed to drive sustainable construction in this country. In conclusion, the status of sustainable construction in Malaysia is still in its infancy. The lack of awareness, training and education, ineffective procurement systems, existing public policies and regulatory frameworks are among the major barriers for sustainable construction in Malaysia. Besides the needs for capacities, technologies and tools, total and ardent commitment by all players in the construction sectors including the governments and the public atlarge are required in order to achieve sustainable construction in Malaysia.

  13. Regeneration of near-wall turbulence structures

    Science.gov (United States)

    Hamilton, James M.; Kim, John J.; Waleffe, Fabian A.

    1993-01-01

    An examination of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the critical Reynolds number conjecture of Waleffe & Kim is presented. The basis is an extension of the 'minimal channel' approach of Jimenez and Moin which emphasizes the near-wall region and further reduces the complexity of the turbulent flow. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. In addition, since each wall may have an active near-wall region, half of the channel is always somewhat redundant. If a plane Couette flow is instead chosen as the base flow, this redundancy is eliminated: the mean shear of a plane Couette flow has a single sign, and at low Reynolds numbers, the two wall regions share a single set of structures. A minimal flow with these modifications possesses, by construction, the strongest constraints which allow sustained turbulence, producing a greatly simplified flow in which the regeneration process can be examined.

  14. Enhanced spin transfer torque effect for transverse domain walls in cylindrical nanowires

    Science.gov (United States)

    Franchin, Matteo; Knittel, Andreas; Albert, Maximilian; Chernyshenko, Dmitri S.; Fischbacher, Thomas; Prabhakar, Anil; Fangohr, Hans

    2011-09-01

    Recent studies have predicted extraordinary properties for transverse domain walls in cylindrical nanowires: zero depinning current, the absence of the Walker breakdown, and applications as domain wall oscillators. In order to reliably control the domain wall motion, it is important to understand how they interact with pinning centers, which may be engineered, for example, through modulations in the nanowire geometry (such as notches or extrusions) or in the magnetic properties of the material. In this paper we study the motion and depinning of transverse domain walls through pinning centers in ferromagnetic cylindrical nanowires. We use (i) magnetic fields and (ii) spin-polarized currents to drive the domain walls along the wire. The pinning centers are modelled as a section of the nanowire which exhibits a uniaxial crystal anisotropy where the anisotropy easy axis and the wire axis enclose a variable angle θP. Using (i) magnetic fields, we find that the minimum and the maximum fields required to push the domain wall through the pinning center differ by 30%. On the contrary, using (ii) spin-polarized currents, we find variations of a factor 130 between the minimum value of the depinning current density (observed for θP=0∘, i.e., anisotropy axis pointing parallel to the wire axis) and the maximum value (for θP=90∘, i.e., anisotropy axis perpendicular to the wire axis). We study the depinning current density as a function of the height of the energy barrier of the pinning center using numerical and analytical methods. We find that for an industry standard energy barrier of 40kBT, a depinning current of about 5μA (corresponding to a current density of 6×1010A/m2 in a nanowire of 10nm diameter) is sufficient to depin the domain wall. We reveal and explain the mechanism that leads to these unusually low depinning currents. One requirement for this depinning mechanism is for the domain wall to be able to rotate around its own axis. With the right barrier design

  15. Determination of the Airborne Sound Insulation of a Straw Bale Partition Wall

    Science.gov (United States)

    Teslík, Jiří; Fabian, Radek; Hrubá, Barbora

    2017-06-01

    This paper describes the results of a scientific project focused on determining of the Airborne Sound Insulation of a peripheral non-load bearing wall made of straw bales expressed by Weighted Sound Reduction Index. Weighted Sound Reduction Index was determined by measuring in the certified acoustic laboratory at the Faculty of Mechanical Engineering at Brno University of Technology. The measured structure of the straw wall was modified in combinations with various materials, so the results include a wide range of possible compositions of the wall. The key modification was application of plaster on both sides of the straw bale wall. This construction as is frequently done in actual straw houses. The additional measurements were performed on the straw wall with several variants of additional wall of slab materials. The airborne sound insulation value has been also measured in separate stages of the construction. Thus it is possible to compare and determinate the effect of the single layers on the airborne sound insulation.

  16. Determination of the Airborne Sound Insulation of a Straw Bale Partition Wall

    Directory of Open Access Journals (Sweden)

    Teslík Jiří

    2017-06-01

    Full Text Available This paper describes the results of a scientific project focused on determining of the Airborne Sound Insulation of a peripheral non-load bearing wall made of straw bales expressed by Weighted Sound Reduction Index. Weighted Sound Reduction Index was determined by measuring in the certified acoustic laboratory at the Faculty of Mechanical Engineering at Brno University of Technology. The measured structure of the straw wall was modified in combinations with various materials, so the results include a wide range of possible compositions of the wall. The key modification was application of plaster on both sides of the straw bale wall. This construction as is frequently done in actual straw houses. The additional measurements were performed on the straw wall with several variants of additional wall of slab materials. The airborne sound insulation value has been also measured in separate stages of the construction. Thus it is possible to compare and determinate the effect of the single layers on the airborne sound insulation.

  17. Developing Innovative Wall Systems that Improve Hygrothermal Performance of Residential Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Robert Tichy; Chuck Murray

    2006-05-31

    This document serves as the Topical Report documenting work completed by Washington State University (WSU) under U.S. Department of Energy Grant, Developing Innovative Wall Systems that Improve Hygrothermal Performance of Residential Buildings. This project was conducted in collaboration with Oak Ridge National Laboratory (ORNL), and includes the participation of several industry partners including Weyerhaeuser, APA - The Engineered Wood Association, CertainTeed Corporation and Fortifiber. This document summarizes work completed by Washington State University August 2002 through June 2006. WSU's primary experimental role is the design and implementation of a field testing protocol that monitored long term changes in the hygrothermal response of wall systems. During the project period WSU constructed a test facility, developed a matrix of test wall designs, constructed and installed test walls in the test facility, installed instrumentation in the test walls and recorded data from the test wall specimens. Each year reports were published documenting the hygrothermal response of the test wall systems. Public presentation of the results was, and will continue to be, made available to the building industry at large by industry partners and the University.

  18. Considerations on the design of through-wall anchors

    International Nuclear Information System (INIS)

    Ricklefs, Ulf

    2012-01-01

    Connections to existing buildings are often the most difficult planning challenge for the realization of construction measures in case of piping system replacements in nuclear power plants. This is due to restricted space or limited load reserves of the building structure. Usually the realization of support connections to the existing buildings is achieved by anchor bolts. But in critical cases the preferred alternative solution uses through-wall anchors. Up to now uniform assessment thresholds are not available, no technical guidelines or regulations for construction variants exist. Through-wall anchors allow significantly higher load capacities for tensile and shear loads but require enhanced planning and realization efforts.

  19. Preliminary Analysis of Reinforced Concrete Waffle Walls

    National Research Council Canada - National Science Library

    Shugar, Theodore

    1997-01-01

    A preliminary analytical method based upon modified plate bending theory is offered for structural analysis of a promising new construction method for walls of small buildings and residential housing...

  20. Design and construction of a time-of-flight wall detector at External Target Facility of HIRFL-CSR

    Science.gov (United States)

    Sun, Y.; Sun, Z. Y.; Yu, Y. H.; Yan, D.; Tang, S. W.; Sun, Y. Z.; Wang, S. T.; Zhang, X. H.; Yue, K.; Fang, F.; Chen, J. L.; Zhang, Y. J.; Hu, B. T.

    2018-06-01

    A Time-Of-Flight Wall (TOFW) detector has been designed and constructed at the External Target Facility (ETF) of HIRFL-CSR. The detector covers a sensitive area of 1.2 × 1.2 m2 and consists of 30 modules. Each module is composed of a long plastic scintillator bar with two photo-multiplier tubes coupled at both ends for readout. The design and manufacture details are described and the test results are reported. The performance of the TOFW detector has been tested and measured with cosmic rays and a 310 MeV/u 40Ar beam. The results show that the time resolutions of all the TOFW modules are better than 128 ps, satisfying the requirements of the experiments which will be carried out at the ETF.

  1. Implementing Green Walls in Schools.

    Science.gov (United States)

    McCullough, Michael B; Martin, Michael D; Sajady, Mollika A

    2018-01-01

    Numerous studies in applied pedagogical design have shown that, at all educational levels, direct exposure to the natural environment can enhance learning by improving student attention and behaviors. Implementing green walls-a "vertical garden," or "living wall" interior wall that typically includes greenery, a growing medium (soil or substrate) and a water delivery system-provides environmental health benefits, but also provides a practical application within classrooms for minimizing directed attention fatigue in students by connecting them to "outdoor nature" within the indoor environment. Hands-on "project-based" learning is another pedagogical strategy that has proved to be effective across the spectrum of educational levels and across subject areas. Green walls have the potential to inspire critical thinking through a combination of project-based learning strategies and environmental education. The authors have outlined a curriculum involving the implementation of an indoor living wall system within a classroom-learning environment, incorporating project-based learning modules that interact with the wall. In conjunction with the passive health benefits of a green wall, project-based curriculum models can connect students interactively with indoor nature and have the potential to inspire real-world thinking related to science, technology, engineering, art, and mathematics fields within the indoor learning environment. Through a combination of these passive and interactive modes, students are connected to nature in the indoor environment regardless of weather conditions outdoors. Future research direction could include post-construction studies of the effectiveness of project-based curricula related to living walls, and the long-term impacts of implementing green walls in classrooms on school achievement and student behaviors.

  2. Seismic fragility analysis of the block masonry wall in nuclear power plants

    International Nuclear Information System (INIS)

    Wang, Z-L.; Pandey, M.D.; Xie, X-C.

    2014-01-01

    The evaluation of seismic fragility of a structure is an integral part in the Seismic Probabilistic Risk Analysis (SPRA). The block masonry wall, a commonly used barrier in nuclear power plants, is fairly vulnerable to failure under an earthquake. In practice, the seismic fragility of block walls is commonly evaluated using a simple deterministic approach called Conservative Deterministic Failure Margin (CDFM) method. This paper presents a more formal fragility analysis of a block wall based on rigorous probabilistic methods and the accuracy of the CDFM method is evaluated by comparison to the more rigorous FA method. (author)

  3. Webs of domain walls in supersymmetric gauge theories

    International Nuclear Information System (INIS)

    Eto, Minoru; Isozumi, Youichi; Nitta, Muneto; Ohashi, Keisuke; Sakai, Norisuke

    2005-01-01

    Webs of domain walls are constructed as 1/4 Bogomol'nyi-Prasad-Sommerfield (BPS) states in d=4, N=2 supersymmetric U(N C ) gauge theories with N F hypermultiplets in the fundamental representation. Webs of walls can contain any numbers of external legs and loops like (p,q) string/5-brane webs. We find the moduli space M of a 1/4 BPS equation for wall webs to be the complex Grassmann manifold. When moduli spaces of 1/2 BPS states (parallel walls) and the vacua are removed from M, the noncompact moduli space of genuine 1/4 BPS wall webs is obtained. All the solutions are obtained explicitly and exactly in the strong gauge coupling limit. In the case of Abelian gauge theory, we work out the correspondence between configurations of wall web and the moduli space CP N F -1

  4. Advanced Extended Plate and Beam Wall System in a Cold-Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, Dave [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, Joseph [Home Innovation Research Labs, Upper Marlboro, MD (United States); Kochkin, Vladimir [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-29

    This report presents the design and evaluation of an innovative wall system. This highly insulated (high-R) light-frame wall system for use above grade in residential buildings is referred to as Extended Plate & Beam (EP&B). The EP&B design is the first of its kind to be featured in a new construction test house (NCTH) for the DOE Building America program. The EP&B wall design integrates standard building methods and common building products to construct a high-R wall that minimizes transition risks and costs to builders. The EP&B design combines optimized framing with integrated rigid foam sheathing to increase the wall system's R-value and reduce thermal bridging. The foam sheathing is installed between the wall studs and structural wood sheathing. The exterior wood sheathing is attached directly to a framing extension formed by extended top and bottom plates. The exterior wood sheathing can dry to the exterior and provides bracing, a clear drainage plane and flashing surface for window and door openings, and a nailing surface for siding attachment. With support of the DOE Building America program, Home Innovation Research Labs partnered with Lancaster County Career and Technology Center (LCCTC) to build a NCTH in Lancaster, PA to demonstrate the EP&B wall design in a cold climate (IECC climate zone 5A). The results of the study confirmed the benefits of the systems and the viability of its integration into the house construction process.

  5. Safety-barrier diagrams as a safety management tool

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2009-01-01

    Safety-barrier diagrams and “bow-tie” diagrams have become popular methods in risk analysis and safety management. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The latter's relation to other methods such as fault trees and Bayesian...

  6. Development of Building Envelope Constructions

    DEFF Research Database (Denmark)

    Tommerup, Henrik Monefeldt; Munch-Andersen, Jørgen; Esbensen, Peter Kjær

    2000-01-01

    It is expected that the heat insulation demands in the Danish Building Regulations will be further increased around 2005, in order to reduce the heating demand and the CO2-emission. A simple increase of the insulation thickness of common wall types seems not to be attractive due to the increased...... effect of the 2-dimensional heat loss, the large wall thickness, and the costs of the wide foundation. Therefore, new types of walls have been developed. It is sought to minimise the total heat loss as well as the material consumption. The target was to come up with new walls for which the construction...

  7. Cell Wall Remodeling Enzymes Modulate Fungal Cell Wall Elasticity and Osmotic Stress Resistance.

    Science.gov (United States)

    Ene, Iuliana V; Walker, Louise A; Schiavone, Marion; Lee, Keunsook K; Martin-Yken, Hélène; Dague, Etienne; Gow, Neil A R; Munro, Carol A; Brown, Alistair J P

    2015-07-28

    The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. The C. albicans cell wall is the first line of defense against external insults, the site of immune recognition by the host, and an attractive target for antifungal therapy. Its tensile strength is conferred by

  8. Reduction of sound transmission through fuselage walls by alternate resonance tuning (A.R.T.)

    Science.gov (United States)

    Bliss, Donald B.; Gottwald, James A.

    1989-01-01

    The ability of alternate resonance tuning (ART) to block sound transmission through light-weight flexible paneled walls by controlling the dynamics of the wall panels is considered. Analytical results for sound transmission through an idealized panel wall illustrate the effect of varying system parameters and show that one or more harmonics of the incident sound field can be cancelled by the present method. Experimental results demonstrate that very large transmission losses with reasonable bandwidths can be achieved by a simple ART panel barrier in a duct.

  9. Evolution Sustainable Green Inner-wall with Flexible Floor Plan

    Directory of Open Access Journals (Sweden)

    Tawil N.M.

    2014-01-01

    Full Text Available The trend of renovate residential houses especially the interior of the house has become a common phenomenon for homeowners nowadays in Malaysia. This scenario is quiet concern because sometimes no modifications to comply with the law and the guidelines set by the government housing. Modifications with not done properly can cause injury and harm to families and the people around. To reduce this problem, the concept of sustainable inner walls with flexible floor plan should be incorporated in every house in Malaysia. This is because the wall is the basic structure of a building and usually serves as the border, supporting structures and dividing the space with another space. Wall also causes an increase of the price of a house. This is due to the increase in raw material costs and labor costs, land subsidence have to bear by the developer. The increasing in house prices is causing among Malaysians, especially young executives cannot afford to buy their first home. To reduce the price of the home, reduction in construction interior wall in wet construction should be done and replaced with the sustainable inner wall. This sustainable inner wall also can save the space and the owner simplify can added or reduced the room according their need without spending too much money for renovation in the future.

  10. Design Analysis and Observed Performance of a Tieback Anchored Pile Wall in Sand

    Directory of Open Access Journals (Sweden)

    Jian-Yong Han

    2017-01-01

    Full Text Available This paper aims to study the design process and service performance of a deep excavation supported by tieback anchored pile walls. The design procedure and design approaches for deep excavation in China are described. Based on the excavation case history for Shenyang, China, design results obtained using the elastic method and the finite element method (FEM are compared and analyzed. Special emphasis is given to the analysis of horizontal wall deformations, internal forces in the wall, earth pressures on the wall, ground surface settlements, and stabilities of the excavation. The similarities and differences between the Chinese code (JGJ 120-2012 and the European code (EN 1997-1 for the design of geotechnical structures are presented based on a design example. Through the comparison, it is indicated that the Chinese code focuses on the design result, while the European code focuses on the design process. The crucial construction methods for reducing construction risk based on the excavation case history are described. The mechanical behaviors of the excavation retained by an anchored pile wall were investigated by analyzing observed field cases. The results provide good, practical guidelines for the design and construction of a tieback anchored pile wall retained excavation in sandy soil.

  11. Perceived barriers to effective job performance among nursing assistants in long-term care.

    Science.gov (United States)

    Parmelee, Patricia A; Laszlo, Mary C; Taylor, Jo A

    2009-10-01

    This research explored perceived barriers to job performance among a national sample of nursing assistants (NAs). Specific objectives were (1) to clarify which of the problems identified by previous research are most troublesome for NAs, (2) to develop a reliable quantitative measure of perceived barriers to job performance, and (3) to test construct validity of the measure vis-à-vis work-related psychological empowerment and job satisfaction. Nursing assistants attending the 2006 national conference of the National Association of Health Care Assistants completed a paper-and-pencil survey including 33 barriers to job performance and standardized measures of empowerment and job satisfaction. The barriers were also rated by a small sample of NAs at a single Georgia nursing home. Factor analysis of barriers items yielded a 30-item Nursing Assistants Barriers Scale (NABS) comprising 6 subscales: Teamwork, Exclusion, Respect, Workload, Work Stress, and New NAs. Lack of teamwork and exclusion from communication processes were rated as most problematic by both samples. The 6 NABS subscales were significantly and independently associated with empowerment and satisfaction; different barriers predicted the 2 constructs. This study is a first step toward quantitative assessment of NAs' perceptions of barriers to doing their jobs. Primary limitations are the select sample and use of a job satisfaction measure that may have artificially inflated correlations with the NABS. Nonetheless, results confirm the validity of the new scale as an operationalization of the barriers construct. The concept of barriers to job performance is a unique construct from work empowerment and satisfaction with one's job. Nursing assistants clearly differentiate various barriers, converging on workload and lack of teamwork as most problematic. Further work is needed to substantiate validity and reliability of the NABS, particularly with respect to NAs' actual job performance, intent to stay on the

  12. Long-Term Drainage from the Riprap Side Slope of a Surface Barrier

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhuanfang

    2017-07-01

    Surface barriers designed to isolate underground nuclear waste in place are expected to function for at least 1000 years. To achieve this long design life, such barriers need to be protected with side slopes against wind- and water-induced erosion and damage by natural or human activities. However, the side slopes are usually constructed with materials coarser than the barrier. Their hydrological characteristics must be understood so that any drainage from them is considered in the barrier design and will not compromise the barrier function. The Prototype Hanford Barrier, an evapotranspiration-capillary (ETC) barrier, was constructed in 1994 at the Hanford Site in southeastern Washington state, with a gravel side slope and a riprap side slope. The soil water content in the gravel side slope and drainage from both side slopes have been monitored since the completion of construction. The monitoring results show that under natural precipitation the annual drainage rates from the two types of side slopes were very similar and about 5 times the typical recharge from local soil with natural vegetation and 40 times the barrier design criterion. The higher recharge from the side slopes results in some of the drainage migrating laterally to the region beneath the ETC barrier. This edge effect of the enhanced drainage was evaluated for a period of 1000 years by numerical simulation. The edge effect was quantified by the amount of water across the barrier edges and the affecting distance of the barrier edges. These results indicate that design features can be adjusted to reduce the edge effect when necessary.

  13. Engineered Barrier Test Facility status report, 1984

    International Nuclear Information System (INIS)

    Phillips, S.J.; Adams, M.R.; Gilbert, T.W.; Meinhardt, C.C.; Mitchell, R.M.; Waugh, W.J.

    1985-02-01

    This report provides a general summary of activities completed to date at the Hanford Engineered Barrier Test Facility. This facility is used to test and compare construction practices and performance of alternative designs of engineered barrier cover systems. These cover systems are being evaluated for potential use for isolation and confinement of buried waste disposal structures

  14. Zirconium-barrier cladding attributes

    International Nuclear Information System (INIS)

    Rosenbaum, H.S.; Rand, R.A.; Tucker, R.P.; Cheng, B.; Adamson, R.B.; Davies, J.H.; Armijo, J.S.; Wisner, S.B.

    1987-01-01

    This metallurgical study of Zr-barrier fuel cladding evaluates the importance of three salient attributes: (1) metallurgical bond between the zirconium liner and the Zircaloy substrate, (2) liner thickness (roughly 10% of the total cladding wall), and (3) softness (purity). The effect that each of these attributes has on the pellet-cladding interaction (PCI) resistance of the Zr-barrier fuel was studied by a combination of analytical model calculations and laboratory experiments using an expanding mandrel technique. Each of the attributes is shown to contribute to PCI resistance. The effect of the zirconium liner on fuel behavior during off-normal events in which steam comes in contact with the zirconium surface was studied experimentally. Simulations of loss-of-coolant accident (LOCA) showed that the behavior of Zr-barrier cladding is virtually indistinguishable from that of conventional Zircaloy cladding. If steam contacts the zirconium liner surface through a cladding perforation and the fuel rod is operated under normal power conditions, the zirconium liner is oxidized more rapidly than is Zircaloy, but the oxidation rate returns to the rate of Zircaloy oxidation when the oxide phase reaches the zirconium-Zircaloy metallurgical bond

  15. Protection against malevolent use of vehicles at Nuclear Power Plants. Vehicle barrier system selection guidance

    International Nuclear Information System (INIS)

    Nebuda, D.T.

    1994-08-01

    This manual provides a simplified procedure for selecting land vehicle barriers that will stop the design basis vehicle threat adopted by the U.S. Nuclear Regulatory Commission. Proper selection and construction of vehicle barriers should prevent intrusion of the design basis vehicle. In addition, vital safety related equipment should survive a design basis vehicle bomb attack when vehicle barriers are properly selected, sited, and constructed. This manual addresses passive vehicle barriers, active vehicle barriers, and site design features that can be used to reduce vehicle impact velocity

  16. Firewalls in bee nests—survival value of propolis walls of wild Cape honeybee ( Apis mellifera capensis)

    Science.gov (United States)

    Tribe, Geoff; Tautz, Jürgen; Sternberg, Karin; Cullinan, Jenny

    2017-04-01

    The Cape bee is endemic to the winter rainfall region of South Africa where fires are an integral part of the ecology of the fynbos (heathland) vegetation. Of the 37 wild nests in pristine Peninsula Sandstone Fynbos in the Cape Point section of Table Mountain National Park that have been analyzed so far, only 22 could be accessed sufficiently to determine the existence of a propolis wall of which 68% had propolis walls which entirely enclosed their openings. The analysis of the 37 wild nests revealed that 78% occurred under boulders or in clefts within rocks, 11% in the ground, 8% in tree cavities, and 3% within shrubs. The analysis of 17 of these nests following a fire within the park revealed that the propolis walls materially protected the nests and retarded the fire with all the colonies surviving. The bees responded to the smoke by imbibing honey and retreating to the furthest recess of their nest cavity. The bees were required to utilize this honey for about 3 weeks after which fire-loving plants appeared and began flowering. Considerable resources were utilized in the construction of the propolis walls, which ranged in thickness from 1.5 to 40 mm (mean 5 mm). Its physical environment determines the nesting behavior of the Cape bee. The prolific use of propolis serves to insulate the nest from extremes of temperature and humidity, restricts entry, camouflages the nest, and acts as an effective fire barrier protecting nests established mostly under rocks in vegetation subjected to periodic fires.

  17. Firewalls in bee nests-survival value of propolis walls of wild Cape honeybee (Apis mellifera capensis).

    Science.gov (United States)

    Tribe, Geoff; Tautz, Jürgen; Sternberg, Karin; Cullinan, Jenny

    2017-04-01

    The Cape bee is endemic to the winter rainfall region of South Africa where fires are an integral part of the ecology of the fynbos (heathland) vegetation. Of the 37 wild nests in pristine Peninsula Sandstone Fynbos in the Cape Point section of Table Mountain National Park that have been analyzed so far, only 22 could be accessed sufficiently to determine the existence of a propolis wall of which 68% had propolis walls which entirely enclosed their openings. The analysis of the 37 wild nests revealed that 78% occurred under boulders or in clefts within rocks, 11% in the ground, 8% in tree cavities, and 3% within shrubs. The analysis of 17 of these nests following a fire within the park revealed that the propolis walls materially protected the nests and retarded the fire with all the colonies surviving. The bees responded to the smoke by imbibing honey and retreating to the furthest recess of their nest cavity. The bees were required to utilize this honey for about 3 weeks after which fire-loving plants appeared and began flowering. Considerable resources were utilized in the construction of the propolis walls, which ranged in thickness from 1.5 to 40 mm (mean 5 mm). Its physical environment determines the nesting behavior of the Cape bee. The prolific use of propolis serves to insulate the nest from extremes of temperature and humidity, restricts entry, camouflages the nest, and acts as an effective fire barrier protecting nests established mostly under rocks in vegetation subjected to periodic fires.

  18. Experience of light thin-walled structures improvement in construction

    Science.gov (United States)

    Frolovskaia, A. V.; Deordiev, S. V.; Falk, A.; Klinduh, N. Y.; Terehova, I. I.

    2018-05-01

    The authors on the basis of practical experience have analyzed low-rise construction with the use of energy-saving technologies. Characteristic features of possible variants of frame construction are looked at and described. The relevance of the paper consists in the improvement of the building frame design solution based on the analysis and elimination of disadvantages taking into account consumers’ point of view.

  19. Parametric Evaluation of Racking Performance of Platform Timber Framed Walls

    OpenAIRE

    Dhonju, R..; D’Amico, B..; Kermani, A..; Porteous, J..; Zhang, B..

    2017-01-01

    This paper provides a quantitative assessment of the racking performance of partially anchored timber framed walls, based on experimental tests. A total of 17 timber framed wall specimens, constructed from a combination of materials under different load configurations, were tested. The experimental study was designed toexamine the influence of a range of geometrical parameters, such as fastener size and spacings, wall length, arrangement of studs and horizontal members, as well as the effect ...

  20. Fractional Brownian motion with a reflecting wall

    Science.gov (United States)

    Wada, Alexander H. O.; Vojta, Thomas

    2018-02-01

    Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior ˜tα , the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α >1 , the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion α implications of these findings, in particular, for applications that are dominated by rare events.

  1. Diastolic timed Vibro-Percussion at 50 Hz delivered across a chest wall sized meat barrier enhances clot dissolution and remotely administered Streptokinase effectiveness in an in-vitro model of acute coronary thrombosis

    OpenAIRE

    Hoffmann, Andrew; Gill, Harjit

    2012-01-01

    Abstract Background Low Frequency Vibro-Percussion (LFVP) assists clearance of thrombi in catheter systems and when applied to the heart and timed to diastole is known to enhance coronary flow. However LFVP on a clotted coronary like vessel given engagement over a chest wall sized barrier (to resemble non-invasive heart attack therapy) requires study. Methods One hour old clots (n=16) were dispensed within a flexible segment of Soft-Flo catheter (4 mm lumen), weighted, interfaced with Heparin...

  2. Walls, Towers, and Sphinxes: Multicultural Concept Construction and Group Inquiry

    Science.gov (United States)

    Bisland, Beverly Milner

    2005-01-01

    One can easily identify the United States of America by the Statue of Liberty, France by the Eiffel Tower, Egypt by its Great Sphinx, and China by its Great Wall. What do these landmarks tell people about these places? What are the characteristics of the place and culture that are symbolized by these landmarks? These questions can serve as the…

  3. Reverse logistics in the construction industry.

    Science.gov (United States)

    Hosseini, M Reza; Rameezdeen, Raufdeen; Chileshe, Nicholas; Lehmann, Steffen

    2015-06-01

    Reverse logistics in construction refers to the movement of products and materials from salvaged buildings to a new construction site. While there is a plethora of studies looking at various aspects of the reverse logistics chain, there is no systematic review of literature on this important subject as applied to the construction industry. Therefore, the objective of this study is to integrate the fragmented body of knowledge on reverse logistics in construction, with the aim of promoting the concept among industry stakeholders and the wider construction community. Through a qualitative meta-analysis, the study synthesises the findings of previous studies and presents some actions needed by industry stakeholders to promote this concept within the real-life context. First, the trend of research and terminology related with reverse logistics is introduced. Second, it unearths the main advantages and barriers of reverse logistics in construction while providing some suggestions to harness the advantages and mitigate these barriers. Finally, it provides a future research direction based on the review. © The Author(s) 2015.

  4. Manufacture and test of prototype water pipe chase barrier in ITER Magnet Feeder system

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Kun, E-mail: lukun@ipp.ac.cn [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Wen, Xinjie; Liu, Chen; Song, Yuntao [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Niu, Erwu [ITER China, 15B Fuxing Road, Beijing 100862 (China); Gung, Chenyu; Su, Man [ITER Organization, Route de Vinon-sur-Verdon – CS 90046, 13067 St Paul-lez-Durance Cedex (France)

    2016-11-01

    The Magnet Feeder system in the International Thermonuclear Experimental Reactor (ITER) deploys electrical currents and supercritical helium to the superconducting magnets and the magnet diagnostic signals to the operators. In the current design, the feeders located in the upper L3 level of the Tokamak gallery penetrate the Tokamak coolant water system vault, the biological shield and the cryostat. As a secondary confinement to contain the activated coolant water in the vault in the case of water pipe burst accident, a water barrier is welded between the penetration in the water pipe chase outer wall and the mid-plane of the vacuum jacket of the Feeder Coil Terminal Box (CTB). A thin-wall stainless steel diaphragm with an omega shape profile is welded around the CTB as the water barrier to endure 2 bar hydraulic pressure. In addition, the barrier is designed as a flexible compensator to withstand a maximum of 15 mm of axial displacement of the CTB in case of helium leak accident without failure. This paper presents the detail configuration, the manufacturing and assembly processes of the water barrier. Test results of the prototype water barrier under simulated accident conditions are also reported. Successful qualification of the design and manufacturing process of the water barrier lays a good foundation for the series production of this subsystem.

  5. Measure Guideline: Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, Joseph [Building Science Corporation, Westford, MA (United States); Baker, Peter [Building Science Corporation, Westford, MA (United States)

    2015-04-01

    This measure guideline provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ inches and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: fundamental building science principles relating to the use of exterior insulation on wall assemblies; design principles for tailoring this use to the specific project goals and requirements; and construction detailing to increase understanding about implementing the various design elements.

  6. Activity measurements of radon from construction materials

    Energy Technology Data Exchange (ETDEWEB)

    Fior, L.; Nicolosi Correa, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Paschuk, S.A., E-mail: spaschuk@gmail.com [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Denyak, V.V. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Schelin, H.R. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Pele Pequeno Principe Research Institute, Av. Silva Jardim, 1632, Curitiba, PR 80250-200 (Brazil); Soreanu Pecequilo, B.R. [Institute of Nuclear and Energetic Researches, IPEN, Av. Prof. Lineu Prestes, 2242-/05508-000 Sao Paulo (Brazil); Kappke, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil)

    2012-07-15

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60 Multiplication-Sign 60 Multiplication-Sign 60 cm{sup 3} were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of {sup 226}Ra, {sup 232}Th and {sup 40}K. The values for the index of the activity concentration (I), radium equivalent activity (Ra{sub eq}), and external hazard index (H{sub ext}) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). - Highlights: Black-Right-Pointing-Pointer Radon activity in air related to building materials was measured. Black-Right-Pointing-Pointer The index of activity concentration of building materials was evaluated. Black-Right-Pointing-Pointer The radium equivalent activity of

  7. Gas permeability of bentonite barriers: development, construction and testing of a measurement system

    Directory of Open Access Journals (Sweden)

    Heraldo Nunes Pitanga

    Full Text Available Abstract This article proposes a testing device to quickly and reliably estimate the gas permeability of bentonite-based clay barriers used in landfill cover systems. The testing methodology is based on a transient gas flow regime that passes through the barrier, therefore not requiring the use of sophisticated equipment that aim to maintain constant differential pressure and measure the gas flow, common requirements for testing methods under a permanent flow regime. To confirm the feasibility of the proposed technique, tests were performed on a pure hydrated bentonite layer, which subsequently encompassed samples of geosynthetic clay liner (GCL at different moisture contents. Geosynthetic clay liners are often selected as a part of the barrier layer for cover systems in solid waste landfills to prevent infiltration of rainfall and migration of biogas into the atmosphere. The results confirmed the equipment reliability and differentiate the different responses of the gas flow barriers studied, considering their different compositions and different moistures.

  8. Failure mechanism of shear-wall dominant multi-story buildings

    Science.gov (United States)

    Yuksel, S.B.; Kalkan, E.

    2008-01-01

    The recent trend in the building industry of Turkey as well as in many European countries is towards utilizing the tunnel form (shear-wall dominant) construction system for development of multi-story residential units. The tunnel form buildings diverge from other conventional reinforced concrete (RC) buildings due to the lack of beams and columns in their structural integrity. The vertical load-carrying members of these buildings are the structural-walls only, and the floor system is a flat plate. Besides the constructive advantages, tunnel form buildings provide superior seismic performance compared to conventional RC frame and dual systems as observed during the recent devastating earthquakes in Turkey (1999 Mw 7.4 Kocaeli, Mw 7.2 Duzce, and 2004 Mw 6.5 Bingol). With its proven earthquake performance, the tunnel form system is becoming the primary construction technique in many seismically active regions. In this study, a series of nonlinear analyses were conducted using finite element (FE) models to augment our understanding on their failure mechanism under lateral forces. In order to represent the nonlinear behavior adequately, The FE models were verified with the results of experimental studies performed on three dimensional (3D) scaled tunnel form building specimens. The results of this study indicate that the structural walls of tunnel form buildings may exhibit brittle flexural failure under lateral loading, if they are not properly reinforced. The global tension/compression couple triggers this failure mechanism by creating pure axial tension in the outermost shear-walls.

  9. Diastolic timed Vibro-Percussion at 50 Hz delivered across a chest wall sized meat barrier enhances clot dissolution and remotely administered Streptokinase effectiveness in an in-vitro model of acute coronary thrombosis

    Directory of Open Access Journals (Sweden)

    Hoffmann Andrew

    2012-11-01

    Full Text Available Abstract Background Low Frequency Vibro-Percussion (LFVP assists clearance of thrombi in catheter systems and when applied to the heart and timed to diastole is known to enhance coronary flow. However LFVP on a clotted coronary like vessel given engagement over a chest wall sized barrier (to resemble non-invasive heart attack therapy requires study. Methods One hour old clots (n=16 were dispensed within a flexible segment of Soft-Flo catheter (4 mm lumen, weighted, interfaced with Heparinized Saline (HS, secured atop a curved dampening base, and photographed. A ~4 cm meat slab was placed over the segment and randomized to receive intermittent LFVP (engaged, - disengaged at 1 second intervals, or no LFVP for 20 minutes. HS was pulsed (~120/80 mmHg, with the diastolic phase coordinated to match LFVP delivery. The segment was then re-photographed and aspirated of fluid to determine post clot weight. The trial was then repeated with 0.5 mls of Streptokinase (15,000 IU/100 microlitre delivered ~ 2 cm upstream from the clot. Results LFVP - HS only samples (vs. controls showed; a development of clot length fluid channels absent in the control group (p Conclusion Diastolic timed LFVP (50 Hz engaged across a chest wall sized barrier enhances clot disruptive effects to an underlying coronary like system.

  10. The Solar Dynamic Buffer Zone (SDBZ) curtain wall: Validation and design of a solar air collector curtain wall

    Science.gov (United States)

    Richman, Russell Corey

    Given the increases in both the environmental and economic costs of energy, there is a need to design and building more sustainable and low-energy building systems now. Curtain wall assemblies show great promise---the spandrel panels within them can be natural solar collectors. By using a Solar Dynamic Buffer Zone (SDBZ) in the spandrel cavity, solar energy can be efficiently gathered using the movement of air. There is a need for a numerical model capable of predicting performance of an SDBZ Curtain Wall system. This research designed, constructed and quantified a prototype SDBZ curtain wall system through by experimental testing in a laboratory environment. The laboratory experiments focussed on three main variables: air flow through the system, incoming radiation and collector surface type. Results from the experimental testing were used to validate a one-dimensional numerical model of the prototype. Results from this research show a SDBZ curtain wall system as an effective means of reducing building heating energy consumption through the preheating of incoming exterior ventilation air during the heating season in cold climates. The numerical model showed good correlation with experimental results at higher operating flows and at lower flows when using an apparent velocity at the heat transfer boundary layer. A seasonal simulation for Toronto, ON predicted energy savings of 205 kWh/m2 with an average seasonal efficiency of 28%. This is considered in the upper range when compared to other solar air collectors. Given the lack of published literature for similar systems, this research acts to introduce a simple, innovative approach to collect solar energy that would otherwise be lost to the exterior using already existing components within a curtain wall. Specifically, the research has provided: results from experiments and simulation, a first generation numerical model, aspects of design and construction of the SDBZ curtain wall and specific directions for further

  11. Feasibility study of tank leakage mitigation using subsurface barriers

    International Nuclear Information System (INIS)

    Treat, R.L.; Peters, B.B.; Cameron, R.J.; McCormak, W.D.; Trenkler, T.; Walters, M.F.; Rouse, J.K.; McLaughlin, T.J.; Cruse, J.M.

    1994-01-01

    The US Department of Energy (DOE) has established the Tank Waste Remediation System (TWRS) to satisfy manage and dispose of the waste currently stored in the underground storage tanks. The retrieval element of TWRS includes a work scope to develop subsurface impermeable barriers beneath SSTs. The barriers could serve as a means to contain leakage that may result from waste retrieval operations and could also support site closure activities by facilitating cleanup. Three types of subsurface barrier systems have emerged for further consideration: (1) chemical grout, (2) freeze walls, and (3) desiccant, represented in this feasibility study as a circulating air barrier. This report contains analyses of the costs and relative risks associated with combinations retrieval technologies and barrier technologies that from 14 alternatives. Eight of the alternatives include the use of subsurface barriers; the remaining six nonbarrier alternative are included in order to compare the costs, relative risks and other values of retrieval with subsurface barriers. Each alternative includes various combinations of technologies that can impact the risks associated with future contamination of the groundwater beneath the Hanford Site to varying degrees. Other potential risks associated with these alternatives, such as those related to accidents and airborne contamination resulting from retrieval and barrier emplacement operations, are not quantitatively evaluated in this report

  12. Multi-application inter-tile synchronization on ultra-high-resolution display walls

    KAUST Repository

    Nam, Sungwon

    2010-01-01

    Ultra-high-resolution tiled-display walls are typically driven by a cluster of computers. Each computer may drive one or more displays. Synchronization between the computers is necessary to ensure that animated imagery displayed on the wall appears seamless. Most tiled-display middleware systems are designed around the assumption that only a single application instance is running in the tiled display at a time. Therefore synchronization can be achieved with a simple solution such as a networked barrier. When a tiled display has to support multiple applications at the same time, however, the simple networked barrier approach does not scale. In this paper we propose and experimentally validate two synchronization algorithms to achieve low-latency, intertile synchronization for multiple applications with independently varying frame rates. The two-phase algorithm is more generally applicable to various highresolution tiled display systems. The one-phase algorithm provides superior results but requires support for the Network Time Protocol and is more CPU-intensive. Copyright 2010 ACM.

  13. Differential protection by cell wall components of Lactobacillus amylovorus DSM 16698Tagainst alterations of membrane barrier and NF-kB activation induced by enterotoxigenic F4+ Escherichia coli on intestinal cells.

    Science.gov (United States)

    Roselli, Marianna; Finamore, Alberto; Hynönen, Ulla; Palva, Airi; Mengheri, Elena

    2016-09-29

    The role of Lactobacillus cell wall components in the protection against pathogen infection in the gut is still largely unexplored. We have previously shown that L. amylovorus DSM 16698 T is able to reduce the enterotoxigenic F4 + Escherichia coli (ETEC) adhesion and prevent the pathogen-induced membrane barrier disruption through the regulation of IL-10 and IL-8 expression in intestinal cells. We have also demonstrated that L. amylovorus DSM 16698 T protects host cells through the inhibition of NF-kB signaling. In the present study, we investigated the role of L. amylovorus DSM 16698 T cell wall components in the protection against F4 + ETEC infection using the intestinal Caco-2 cell line. Purified cell wall fragments (CWF) from L. amylovorus DSM 16698 T were used either as such (uncoated, U-CWF) or coated with S-layer proteins (S-CWF). Differentiated Caco-2/TC7 cells on Transwell filters were infected with F4 + ETEC, treated with S-CWF or U-CWF, co-treated with S-CWF or U-CWF and F4 + ETEC for 2.5 h, or pre-treated with S-CWF or U-CWF for 1 h before F4 + ETEC addition. Tight junction (TJ) and adherens junction (AJ) proteins were analyzed by immunofluorescence and Western blot. Membrane permeability was determined by phenol red passage. Phosphorylated p65-NF-kB was measured by Western blot. We showed that both the pre-treatment with S-CWF and the co- treatment of S-CWF with the pathogen protected the cells from F4 + ETEC induced TJ and AJ injury, increased membrane permeability and activation of NF-kB expression. Moreover, the U-CWF pre-treatment, but not the co-treatment with F4 + ETEC, inhibited membrane damage and prevented NF-kB activation. The results indicate that the various components of L. amylovorus DSM 16698 T cell wall may counteract the damage caused by F4 + ETEC through different mechanisms. S-layer proteins are essential for maintaining membrane barrier function and for mounting an anti-inflammatory response against F4 + ETEC infection. U-CWF are

  14. FELIX construction status and experimental program

    International Nuclear Information System (INIS)

    Turner, L.R.; Praeg, W.F.; Knott, M.J.; Lari, R.J.; McGhee, D.G.; Wehrle, R.B.

    1983-01-01

    FELIX (Fusion Electromagnetic Induction Experiment) is an experimental test facility being constructed at Argonne National Laboratory (ANL) for the study of electromagnetic effects in the first wall/blanket/shield (FWBS) systems of fusion reactors. The facility design, construction status, experimental program, instrumentation, and associated computer-code comparisons are described

  15. Optimum Design of Gravity Retaining Walls Using Charged System Search Algorithm

    Directory of Open Access Journals (Sweden)

    S. Talatahari

    2012-01-01

    Full Text Available This study focuses on the optimum design retaining walls, as one of the familiar types of the retaining walls which may be constructed of stone masonry, unreinforced concrete, or reinforced concrete. The material cost is one of the major factors in the construction of gravity retaining walls therefore, minimizing the weight or volume of these systems can reduce the cost. To obtain an optimal seismic design of such structures, this paper proposes a method based on a novel meta-heuristic algorithm. The algorithm is inspired by the Coulomb's and Gauss’s laws of electrostatics in physics, and it is called charged system search (CSS. In order to evaluate the efficiency of this algorithm, an example is utilized. Comparing the results of the retaining wall designs obtained by the other methods illustrates a good performance of the CSS. In this paper, we used the Mononobe-Okabe method which is one of the pseudostatic approaches to determine the dynamic earth pressure.

  16. IBS SURVEY 2010: DRIVERS, BARRIERS AND CRITICAL SUCCESS FACTORS IN ADOPTING INDUSTRIALISED BUILDING SYSTEM (IBS CONSTRUCTION BY G7 CONTRACTORS IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    KAMARUL ANUAR MOHAMAD KAMAR

    2014-08-01

    Full Text Available The industrialised building system (IBS survey has become an essential tool for ensuring the IBS Roadmap (2003 to 2010 meets its goals and target. As part of the process review survey, it also records the trend achievement of Malaysia in the usage of IBS in the building construction industry. The first and second IBS surveys were published in 2003 and 2005, respectively. Afterward, the IBS Roadmap’s midterm review was conducted. The third and the most recent IBS surveys were conducted in 2008 and 2010, respectively. This paper aims to highlight a part of the IBS survey report in 2010, which has been conducted to measure the drivers, barriers and the critical success factors of G7 contractors in adopting IBS construction. G7 is a Construction Industry Development Board contractor grade that can apply tender without limit. The importance of this paper is that it guides the policy and implementation strategy of IBS by G7 contractors. The survey shows that the acceptance, adoption, and deployment of IBS in the Malaysian construction industry are still low and do not address the persisting problems, such as productivity, dependency on foreign workers and high level of construction wastage.

  17. INTEGRATED ENERGY EFFICIENT WINDOW-WALL SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Michael Arney, Ph.D.

    2002-12-31

    The building industry faces the challenge of reducing energy use while simultaneously improving construction methods and marketability. This paper describes the first phase of a project to address these concerns by designing an Integrated Window Wall System (IWWS) that can be commercialized. This work builds on previous research conducted during the 1990's by Lawrence Berkeley national Laboratories (LBNL). During this phase, the objective was to identify appropriate technologies, problems and issues and develop a number of design concepts. Four design concepts were developed into prototypes and preliminary energy analyses were conducted Three of these concepts (the foam wall, steel wall, and stiffened plate designs) showed particular potential for meeting the project objectives and will be continued into a second phase where one or two of the systems will be brought closer to commercialization.

  18. A mobility based vibroacoustic energy transmission simulation into an enclosure through a double-wall panel.

    Science.gov (United States)

    Sahu, Atanu; Bhattacharya, Partha; Niyogi, Arup Guha; Rose, Michael

    2017-06-01

    Double-wall panels are known for their superior sound insulation properties over single wall panels as a sound barrier. The sound transmission phenomenon through a double-wall structure is a complex process involving vibroacoustic interaction between structural panels, the air-cushion in between, and the secondary acoustic domain. It is in this context a versatile and a fully coupled technique based on the finite-element-boundary element model is developed that enables estimation of sound transfer through a double-wall panel into an adjacent enclosure while satisfying the displacement compatibility across the interface. The contribution of individual components in the transmitted energy is identified through numerical simulations.

  19. The new technology of dividing wall in stope

    International Nuclear Information System (INIS)

    Li Zhiguo

    1999-01-01

    The author analyzes advantages and disadvantages of the ordinary separating methods between stopes at deep mine, points out the main problems of the original projects constructing dividing wall, presents an idea of new technology which can overcome the main problems, predicts effect adopting the new technology, and analyzes that feasibility applying the new technology to construct mortar pad in stope and dyke-dam

  20. Dynamic responses of connections in road safety barriers

    International Nuclear Information System (INIS)

    Bayton, D.A.F.; Long, R.; Fourlaris, G.

    2009-01-01

    Bolted road safety barrier connections utilise slotted holes that are perpendicular to the direction of the safety barrier beam. Due to the clearance between the slotted holes and the bolts, a varying amount of slippage is seen before contact with the edge of the slot is made. The stiffness characteristics of bolted road safety barrier connections have been examined with a representative test coupon that incorporates a full size safety barrier connection slot to industry standard dimensions. Previous research work has successfully determined the stiffness characteristics of the bolted connections at quasi-static strain rates. Representative non-linear finite element models of the bolted test coupons have been constructed. When compared to the laboratory results the initial stiffness, maximum force and displacement of the bolted connections are similar to the finite element model predictions. Current investigations have moved onto strain rates comparable to those observed in actual vehicle crash tests. Explicit dynamic finite element (FE) models have been constructed and validated, using experimental data produced using a series of high strain rate laboratory tests for a number of bolt configurations

  1. 200-BP-1 Prototype Hanford Barrier -- 15 Years of Performance Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Anderson L.; Draper, Kathryn E.; Link, Steven O.; Clayton, Ray E.

    2011-09-30

    Monitoring is an essential component of engineered barrier system design and operation. A composite capacitive cover, including a capillary break and an evapotranspiration (ET) barrier at the Hanford Site, is generating data that can be used to help resolve these issues. The prototype Hanford barrier was constructed over the 216-B-57 Crib in 1994 to evaluate surface-barrier constructability, construction costs, and physical and hydrologic performance at the field scale. The barrier has been routinely monitored between November 1994 and September 1998 as part of a Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) treatability test of barrier performance for the 200 BP 1 Operable Unit. Since FY 1998, monitoring has focused on a more limited set of key water balance, stability, and biotic parameters. In FY 2009, data collection was focused on: (1) water-balance monitoring, consisting of precipitation, runoff, soil moisture storage, and drainage measurements with evapotranspiration calculated by difference; (2) stability monitoring, consisting of asphalt-layer-settlement, basalt-side-slope-stability, and surface-elevation measurements; (3) vegetation dynamics; and (4) animal use. September 2009 marked 15 years since the start of monitoring and the collection of performance data. This report describes the results of monitoring activities during the period October 1, 2008, through September 30, 2009, and summarizes the 15 years of performance data collected from September 1994 through September 2009.

  2. Trombe walls with nanoporous aerogel insulation applied to UK housing refurbishments

    Directory of Open Access Journals (Sweden)

    Mark Dowson

    2014-10-01

    Full Text Available There is an opportunity to improve the efficiency of passive Trombe walls and active solar air collectors by replacing their conventional glass covers with lightweight polycarbonate panels filled with nanoporous aerogel insulation. This study investigates the thermal performance, energy savings, and financial payback period of passive Aerogel Trombe walls applied to the existing UK housing stock. Using parametric modeling, a series of design guidance tables have been generated, providing estimates of the energy savings and overheating risk associated with applying areas of Trombe wall to four different house types across the UK built to six notional construction standards. Calculated energy savings range from 183 kWh/m2/year for an 8 m2 system retrofitted to a solid walled detached house to 62 kWh/m2/year for a 32 m2 system retrofitted to a super insulated flat. Predicted energy savings from Trombe walls up to 24 m2 are found to exceed the energy savings from external insulation across all house types and constructions. Small areas of Trombe wall can provide a useful energy contribution without creating a significant overheating risk. If larger areas are to be installed, then detailed calculations would be recommended to assess and mitigate potential overheating issues.

  3. Infiltration barrier demonstration at Maxey Flats, Kentucky

    International Nuclear Information System (INIS)

    Mills, D.; Razor, J.

    1983-01-01

    At the 1982 DOE LLWMP meeting, the Kentucky Natural Resources and Environmental Protection Cabinet presented a history of the Maxey Flats Waste Disposal Facility, its status, and current Commonwealth activities leading toward stabilization and decommissioning. Information was presented at that time on the purpose of the DOE Trench Moisture Barrier Demonstration Grant and the early phases of construction and implementation. In this paper, final construction and implementation of the trench moisture barrier demonstration are discussed. Data including trench water level measurements, lateral liquid flow in experimental sections, and soil moisture measurements are presented and discussed. The Paper is completed with a brief discussion of remediation activities currently being implemented at Maxey Flats. 9 references, 7 figures, 1 table

  4. Compressive behavior of energy-saving fired facing brick composite wall

    Science.gov (United States)

    Guo, Kai; Wu, Cai

    2018-03-01

    The energy-saving fired facing brick composite wall has a broad development prospects due to its merits of thermal insulation, energy conservation, beautiful, and natural. The construction and characteristics of this wall are introduced and analyzed in this paper. Experimental studies of samples are also conducted to investigate its compressive performance. The results show that the energy-saving fired facing brick composite wall has high compressive capacity. It has considerable application prospect, the study in this paper provides foundation to further studies.

  5. Mechanical performance and sustainability assessment of reinforced soil walls

    OpenAIRE

    Puig Damians, Ivan

    2016-01-01

    Soil reinforced retaining wall structures are materiallymore efficientthan competing construction solutions such as gravity and cantilever walls. Nevertheless, the behaviour and interactions between the com ponent materials are com plex and not fully understood. Current design methods are typically limited to simple cases with respect to material properties, geometry, and boundary conditions. Advanced numerical models using finite element and/or finite difference methods offer the possibility...

  6. FELIX construction status and experimental program

    International Nuclear Information System (INIS)

    Turner, L.R.; Peag, W.F.

    1983-01-01

    FELIX (Fusion Electromagnetic Induction eXperiment) is an experimental test facility being constructed at Argonne National Laboratory (ANL) for the study of electromagnetic effects in the first wall/blanket/shield (FWBS) systems of fusion reactors. The facility design, construction status, experimental program, instrumentation, and associated computer-code comparisons are described

  7. Wall Street sours on nuke plants

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Wall Street has been threatening to join the antinuclear campaign for years as construction lead times and costs grew and the financial condition of utilities building reactors deteriorated. With nuclear plant cancellations, licensing problems, quality-assurance breakdowns, and elevated costs, stock prices have dropped causing unrest among utility investors

  8. ANALISIS FAKTOR PENGHAMBAT EKSPOR BAGI UKM Small and Medium Enterprise’s Export Barrier Factor Analyses

    Directory of Open Access Journals (Sweden)

    Elvia Ivada

    2015-12-01

    Full Text Available The intention of this research are to analyze Small and Medium Enterprises’ export barriers in Solo Raya (Surakarta, Boyolali, Sukoharjo, Karanganyar, Wonogiri, Sragen, Klaten and to prove that all indicators which are knowledge barriers, resources barriers, procedurs barriers and exogenous barrier support export barriers as its construct. This research provides a measurement tool for the next export barriers research as well This study combines questioner’s statements  that were developed by researchers from  previous studies in European countries and export obstacle expressions suggested by Indonesian’s expert. Using Small and Medium Enterprises in Solo Raya region as its respondent sample, and we can collect 400 respondent of SME.  There was no such researches in Indonesia before, thus this is the first study using export barrier’s questioner. That’s why Structural Equation Modelling (SEM is used to provide all construct variables and their indicators become acceptable as a measurement tool for this kind of research. When the researcher run the data using SEM, it showed that construct variables can  support the model. In other words, the model does fit the datas. Except for the exogenous barriers that don’t have significant influence to other two barrier which are resources and procedures.

  9. Break the "wall" and become creative: Enacting embodied metaphors in virtual reality.

    Science.gov (United States)

    Wang, Xinyue; Lu, Kelong; Runco, Mark A; Hao, Ning

    2018-07-01

    This study investigated whether the experience of "breaking the walls", the embodiment of the metaphor "breaking the rules", could enhance creative performance. The virtual reality technology was used to simulate the scenario where participants could "break the walls" while walking in a corridor. Participants were asked to solve the creativity-demanding problems (ie., alternative uses tasks, AUT) in either the "break" condition in which they had to break the walls to move forward in VR, or the "no-break" condition where no barrier walls would appear. Results showed higher AUT originality and AUT fluency in the "break" condition than in the "no-break" condition. Moreover, the effects of "breaking the walls" on AUT originality were fully mediated by cognitive flexibility and persistence. These findings may indicate that enacting metaphors such as "breaking the rules" contribute to creative performance. The enhanced cognitive flexibility and persistence may account for the benefits. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Improvements in or relating to thermal barrier systems

    International Nuclear Information System (INIS)

    Birch, W.; Pearson, R.

    1976-01-01

    Reference is made to thermal barrier systems for the internal surface of gas cooled reactor prestressed concrete pressure vessels. Provision has to be made to anchor the thermal barrier system to a metal limit within the pressure vessel, and the object of the arrangement described is to provided a suitable attachment means. The thermal barrier may consist of a number of plates arranged in overlapped fashion or having flexible joint portions. A problem that arises concerns anchoring of the hot plates to the cold pressure vessel by a rigid attachment, and the design must be such as to ensure adequate bending and axial strength compatible with a minimum heat conduction area and allowable thermal stress. The arrangement must also allow easy installation. The arrangement described also provides for a 'fail-safe' structure. It comprises a metal stud with a hollow body; two or more helical channels are provided through the side walls of the body. The body portion expands or contracts to accommodate axial temperature gradient stress set up by the temperature difference between the pressure vessel and the thermal barrier. The space between the thermal barrier and the pressure vessel may contain solid insulating material. (U.K.)

  11. Acoustic impact on the laminated plates placed between barriers

    Science.gov (United States)

    Paimushin, V. N.; Gazizullin, R. K.; Fedotenkov, G. V.

    2016-11-01

    On the basis of previously derived equations, analytical solutions are established on the forced vibrations of two-layer and three-layers rectangular plates hinged in an opening of absolutely rigid walls during the transmission of monoharmonic sound waves. It is assumed that the partition wall is situated between two absolutely rigid barriers, one of them by harmonic oscillation with a given displacements amplitude on the plate forms the incident sound wave, and the other is stationary and has a coating of deformable energy absorbing material with high damping properties. The behavior of acoustic environments in the spaces between the deformable plate and the barriers described by classical wave equation based on the ideal compressible fluid model. To describe the process of dynamic deformation of the energy absorbing coating of fixed barrier, two-dimensional equations of motion based on the use of models transversely soft layer are derived with a linear approximation of the displacement field in the thickness direction of the coating and taking into account the damping properties of the material and the hysteresis model for it. The influence of the physical and mechanical properties of the concerned mechanical system and the frequency of the incident sound wave on the parameters of its insulation properties of the plate, as well as on the parameters of the stress-strain state of the plate has been analyzed.

  12. HRE-Pond Cryogenic Barrier Technology Demonstration: Pre- and Post-Barrier Hydrologic Assessment

    International Nuclear Information System (INIS)

    Moline, G.R.

    1999-01-01

    The Homogeneous Reactor Experiment (HRE) Pond is the site of a former impoundment for radioactive wastes on the Oak Ridge Reservation (ORR) in east Tennessee. The pond received radioactive wastes from 1957 to 1962, and was subsequently drained, filled with soil, and covered with an asphalt cap. The site is bordered to the east and south by an unnamed stream that contains significant concentrations of radioactive contaminants, primarily 90 Sr. Because of the proximity of the stream to the HRE disposal site and the probable flow of groundwater from the site to the stream, it was hypothesized that the HRE Pond has been a source of contamination to the creek. The HRE-Pond was chosen as the site of a cryogenic barrier demonstration to evaluate this technology as a means for rapid, temporary isolation of contaminants in the type of subsurface environment that exists on the ORR. The cryogenic barrier is created by the circulation of liquid CO 2 through a system of thermoprobes installed in boreholes which are backfilled with sand. The probes cool the subsurface, creating a vertical ice wall by freezing adjacent groundwater, effectively surrounding the pond on four sides. The purpose of this investigation was to evaluate the hydrologic conditions within and around the pond prior to, during, and after the cryogenic barrier emplacement. The objectives were (1) to provide a hydrologic baseline for post-banner performance assessment, (2) to confirm that the pond is hydraulically connected to the surrounding sediments, (3) to determine the likely contaminant exit pathways from the pond, and (4) to measure changes in hydrologic conditions after barrier emplacement in order to assess the barrier performance. Because relatively little information about the subsurface hydrology and the actual configuration of the pond existed, data from multiple sources was required to reconstruct this complex system

  13. LONG-TERM GEOCHEMICAL BEHAVIOR OF A ZEROVALENT IRON PERMEABLE REACTIVE BARRIER FOR THE TREATMENT OF HEXAVALENT CHROMIUM IN GROUNDWATER

    Science.gov (United States)

    Passive, in-situ reactive barriers have proven to be viable, cost-effective systems for the remediation of Cr-contaminated groundwater at some sites. Permeable reactive barriers (PRBs) are installed in the flow-path of groundwater, most typically as vertical treatment walls. Re...

  14. Vertical barriers with increased sorption capacities

    International Nuclear Information System (INIS)

    Bradl, H.B.

    1997-01-01

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed 'tailor-made' depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents

  15. Electrical insulator assembly with oxygen permeation barrier

    Science.gov (United States)

    Van Der Beck, Roland R.; Bond, James A.

    1994-01-01

    A high-voltage electrical insulator (21) for electrically insulating a thermoelectric module (17) in a spacecraft from a niobium-1% zirconium alloy wall (11) of a heat exchanger (13) filled with liquid lithium (16) while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator (21) has a single crystal alumina layer (SxAl.sub.2 O.sub.3, sapphire) with a niobium foil layer (32) bonded thereto on the surface of the alumina crystal (26) facing the heat exchanger wall (11), and a molybdenum layer (31) bonded to the niobium layer (32) to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface.

  16. Implementing Green Walls in Schools

    Directory of Open Access Journals (Sweden)

    Michael B. McCullough

    2018-06-01

    Full Text Available Numerous studies in applied pedagogical design have shown that, at all educational levels, direct exposure to the natural environment can enhance learning by improving student attention and behaviors. Implementing green walls—a “vertical garden,” or “living wall” interior wall that typically includes greenery, a growing medium (soil or substrate and a water delivery system—provides environmental health benefits, but also provides a practical application within classrooms for minimizing directed attention fatigue in students by connecting them to “outdoor nature” within the indoor environment. Hands-on “project-based” learning is another pedagogical strategy that has proved to be effective across the spectrum of educational levels and across subject areas. Green walls have the potential to inspire critical thinking through a combination of project-based learning strategies and environmental education. The authors have outlined a curriculum involving the implementation of an indoor living wall system within a classroom-learning environment, incorporating project-based learning modules that interact with the wall. In conjunction with the passive health benefits of a green wall, project-based curriculum models can connect students interactively with indoor nature and have the potential to inspire real-world thinking related to science, technology, engineering, art, and mathematics fields within the indoor learning environment. Through a combination of these passive and interactive modes, students are connected to nature in the indoor environment regardless of weather conditions outdoors. Future research direction could include post-construction studies of the effectiveness of project-based curricula related to living walls, and the long-term impacts of implementing green walls in classrooms on school achievement and student behaviors.

  17. 9 CFR 108.8 - Construction of buildings.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Construction of buildings. 108.8 Section 108.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... LICENSED ESTABLISHMENTS § 108.8 Construction of buildings. (a) The floors, walls, ceilings, partitions...

  18. Thermal stress and creep fatigue limitations in first wall design

    International Nuclear Information System (INIS)

    Majumdar, S.; Misra, B.; Harkness, S.D.

    1977-01-01

    The thermal-hydraulic performance of a lithium cooled cylindrical first wall module has been analyzed as a function of the incident neutron wall loading. Three criteria were established for the purpose of defining the maximum wall loading allowable for modules constructed of Type 316 stainless steel and a vanadium alloy. Of the three, the maximum structural temperature criterion of 750 0 C for vanadium resulted in the limiting wall loading value of 7 MW/m 2 . The second criterion limited thermal stress levels to the yield strength of the alloy. This led to the lowest wall loading value for the Type 316 stainless steel wall (1.7 MW/m 2 ). The third criterion required that the creep-fatigue characteristics of the module allow a lifetime of 10 MW-yr/m 2 . At wall temperatures of 600 0 C, this lifetime could be achieved in a stainless steel module for wall loadings less than 3.2 MW/m 2 , while the same lifetime could be achieved for much higher wall loadings in a vanadium module

  19. 27 CFR 555.207 - Construction of type 1 magazines.

    Science.gov (United States)

    2010-04-01

    ... constructed of, or covered with, a nonsparking material. (3) Wood frame wall construction. The exterior of... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Construction of type 1... Construction of type 1 magazines. A type 1 magazine is a permanent structure: a building, an igloo or “Army...

  20. 41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

    Science.gov (United States)

    2010-07-01

    ... PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the Architectural Barriers Act apply? (a) The Architectural Barriers Act applies to any facility that is intended... the Architectural Barriers Act apply? 102-76.60 Section 102-76.60 Public Contracts and Property...

  1. USE OF PERFLUOROCARBON TRACER (PFT) TECHNOLOGY FOR SUBSURFACE BARRIER INTEGRITY VERIFICATION AT THE WALDO TEST SITE

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN,T.; HEISER,J.; SENUM,G.; MILLIAN,L.

    2000-02-27

    Researchers from Brookhaven National Laboratory (BNL) tested perfluorocarbon (PFT) gas tracers on a subsurface barrier with known flaws at the Waldo test facility [operated by Science and Engineering Associates, Inc (SEA)]. The tests involved the use of five unique PFT tracers with a different tracer injected along the interior of each wall of the barrier. A fifth tracer was injected exterior to the barrier to examine the validity of diffusion controlled transport of the PFTs. The PFTs were injected for three days at a nominal flow rate of 15 cm{sup 3}/min and a concentrations in the range of a few hundred ppm. Approximately 65 liters of air laced with tracer was injected for each tracer. The tracers were able to accurately detect the presence of the engineered flaws. Two flaws were detected on the north and east walls and lane flaw was detected on the south and west walls. In addition, one non-engineered flaw at the seam between the north and east walls was also detected. The use of multiple tracers provided independent confirmation of the flaws and permitted a distinction between tracers arriving at a monitoring port after being released from a nearby flaw and non-engineered flaws. The PFTs detected the smallest flaw, 0.5 inches in diameter. Visual inspection of the data showed excellent agreement with the known flaw locations and the relative size of the flaws was accurately estimated.

  2. Regulatory analysis for the use of underground barriers at the Hanford Site tank farms

    International Nuclear Information System (INIS)

    Hampsten, K.L.

    1994-01-01

    Sixty-seven of the single-shell tanks at the Hanford Site, Richland, Washington, are assumed to have leaked in the past. Some of the waste retrieval options being considered, such as past-practice sluicing (a process that uses hot water to dislodge waste for subsequent removal by pumping), have the potential for increasing releases of dangerous waste from these tanks. Underground barrier systems are being evaluated as a method to mitigate releases of tank waste to the soil and groundwater that may occur during retrieval activities. The following underground barrier system options are among those being evaluated to determine whether their construction at the Single-Shell Tank Farms is viable. (1) A desiccant barrier would be created by circulating air through the subsurface soil to lower and then maintain the water saturation below the levels required for liquids to flow. (2) An injected materials barrier would be created by injecting materials such as grout or silica into the subsurface soils to form a barrier around and under a given tank or tank farm. (3) A cryogenic barrier would be created by freezing subsurface soils in the vicinity of a tank or tank farm. An analysis is provided of the major regulatory requirements that may impact full scale construction and operation of an underground barrier system and a discussion of factors that should be considered throughout the barrier selection process, irrespective of the type of underground barrier system being considered. However, specific barrier systems will be identified when a given regulation will have significant impact on a particular type of barrier technology. Appendix A provides a matrix of requirements applicable to construction and operation of an underground barrier system

  3. Design, Production, and Installation of Wooden Walls for the Japan Pavilion at Expo 2015

    Directory of Open Access Journals (Sweden)

    Matteo Cipollini

    2016-10-01

    Full Text Available This article illustrates the production process, the structural calculations and the assembly phases of the wooden walls of the Japan Pavilion at Expo 2015 in Milan, designed by Atsushi Kitagawara Architects (AKA. The pavilion, one of the most popular construction of this international event, was built almost exclusively with precast interlocking. The production process and the assembly phases were optimized to construct the wooden walls (with a height of 4–12 m in a short time frame and with a high level of quality. Out-of-plane rocking and other aspects of structural safety were considered, to ensure sufficient stability of the walls.

  4. A New Model for Optimal Mechanical and Thermal Performance of Cement-Based Partition Wall.

    Science.gov (United States)

    Huang, Shiping; Hu, Mengyu; Huang, Yonghui; Cui, Nannan; Wang, Weifeng

    2018-04-17

    The prefabricated cement-based partition wall has been widely used in assembled buildings because of its high manufacturing efficiency, high-quality surface, and simple and convenient construction process. In this paper, a general porous partition wall that is made from cement-based materials was proposed to meet the optimal mechanical and thermal performance during transportation, construction and its service life. The porosity of the proposed partition wall is formed by elliptic-cylinder-type cavities. The finite element method was used to investigate the mechanical and thermal behaviour, which shows that the proposed model has distinct advantages over the current partition wall that is used in the building industry. It is found that, by controlling the eccentricity of the elliptic-cylinder cavities, the proposed wall stiffness can be adjusted to respond to the imposed loads and to improve the thermal performance, which can be used for the optimum design. Finally, design guidance is provided to obtain the optimal mechanical and thermal performance. The proposed model could be used as a promising candidate for partition wall in the building industry.

  5. A New Model for Optimal Mechanical and Thermal Performance of Cement-Based Partition Wall

    Directory of Open Access Journals (Sweden)

    Shiping Huang

    2018-04-01

    Full Text Available The prefabricated cement-based partition wall has been widely used in assembled buildings because of its high manufacturing efficiency, high-quality surface, and simple and convenient construction process. In this paper, a general porous partition wall that is made from cement-based materials was proposed to meet the optimal mechanical and thermal performance during transportation, construction and its service life. The porosity of the proposed partition wall is formed by elliptic-cylinder-type cavities. The finite element method was used to investigate the mechanical and thermal behaviour, which shows that the proposed model has distinct advantages over the current partition wall that is used in the building industry. It is found that, by controlling the eccentricity of the elliptic-cylinder cavities, the proposed wall stiffness can be adjusted to respond to the imposed loads and to improve the thermal performance, which can be used for the optimum design. Finally, design guidance is provided to obtain the optimal mechanical and thermal performance. The proposed model could be used as a promising candidate for partition wall in the building industry.

  6. Hydraulic performance of permeable barriers for in situ treatment of contaminated groundwater

    International Nuclear Information System (INIS)

    Smyth, D.J.A.; Shikaze, S.G.; Cherry, J.A.

    1997-01-01

    The passive interception and in situ treatment of dissolved contaminants in groundwater by permeable reactive barriers has recently gained favor at an increasing number of sites as an alternative to conventional approaches to groundwater remediation such as the pump-and-treat method. Permeable reactive barriers have two essential functions. The first is that the barriers must be installed in a position such that all of the plume passes through the reactive system. The second function is to achieve acceptable treatment of the contamination by physical, chemical or biological means within or downgradient of the barrier. In this paper, issues associated with the hydraulic performance of permeable reaction barriers are evaluated using a three-dimensional groundwater flow model. The efficiency of plume capture by permeable wall and funnel-and-gate systems is examined for some generic and for site-specific hydrogeologic systems. The results have important implications to decisions pertaining to the selection, design and installation of permeable reactive barrier systems

  7. Uranium City radiation reduction program: further studies on remedial measures and radon infiltration routes for houses with block walls

    International Nuclear Information System (INIS)

    Leung, M.K.

    1980-01-01

    This report describes the results of tests of partial sealing of concrete block walls to prevent radon infiltration into houses in Uranium City, and gives the results of studies of radon migration through concrete block walls. Results of some laboratory tests on the effectiveness of concrete blocks as a radon barrier are included

  8. Scalable Resolution Display Walls

    KAUST Repository

    Leigh, Jason; Johnson, Andrew; Renambot, Luc; Peterka, Tom; Jeong, Byungil; Sandin, Daniel J.; Talandis, Jonas; Jagodic, Ratko; Nam, Sungwon; Hur, Hyejung; Sun, Yiwen

    2013-01-01

    This article will describe the progress since 2000 on research and development in 2-D and 3-D scalable resolution display walls that are built from tiling individual lower resolution flat panel displays. The article will describe approaches and trends in display hardware construction, middleware architecture, and user-interaction design. The article will also highlight examples of use cases and the benefits the technology has brought to their respective disciplines. © 1963-2012 IEEE.

  9. Wall insulation system

    Energy Technology Data Exchange (ETDEWEB)

    Kostek, P.T.

    1987-08-11

    In a channel specially designed to fasten semi-rigid mineral fibre insulation to masonry walls, it is known to be constructed from 20 gauge galvanized steel or other suitable material. The channel is designed to have pre-punched holes along its length for fastening of the channel to the drywall screw. The unique feature of the channel is the teeth running along its length which are pressed into the surface of the butted together sections of the insulation providing a strong grip between the two adjacent pieces of insulation. Of prime importance to the success of this system is the recent technological advancements of the mineral fibre itself which allow the teeth of the channel to engage the insulation fully and hold without mechanical support, rather than be repelled or pushed back by the inherent nature of the insulation material. After the insulation is secured to the masonry wall by concrete nail fastening systems, the drywall is screwed to the channel.

  10. Hanford Site protective isolation surface barrier: Taking research and development to engineered application

    International Nuclear Information System (INIS)

    Myers, D.R.; Wing, N.R.

    1994-01-01

    The development of the Protective Isolation Surface Barrier has been an ongoing program since 1985. This development effort has focused on several technical areas. These technical areas include water infiltration, biointrusion, human intrusion, erosion/deposition, physical stability, barrier materials, computer modeling, long-term climate effects, natural analogs, and barrier design. This paper briefly reviews the results of the research and development in the technical areas and then explains how the results of this work have influenced the design features of the prototype barrier. A good example of this is to explain how the type and depth of the soil layer used in the barrier is related to water infiltration, biointrusion, modeling, climate, analogs, and barrier materials. Another good example is to explain the relationship of the barrier sideslopes (basalt riprap and native soil) with human intrusion, biointrusion, barrier materials, and barrier design. In general, the design features of the prototype barrier will be explained in terms of the results of the testing and development program. After the basis for prototype barrier design has been established, the paper will close by reviewing the construction of the prototype barrier, sharing the lessons learned during construction, and explaining the ongoing testing and monitoring program which will determine the success or failure of this barrier concept and the need for additional design modifications

  11. Protective measures during construction against radon exposure

    International Nuclear Information System (INIS)

    Horn, W.

    1990-01-01

    Radon, thoron as well as their daughter products have an cancerogeneous effect on the human respiratory tracts. In this respect protective measures in the area of construction are of great importance. This article deals with constructional solutions which consist of different individual measures. Sources of radon are outside air, water, fuels, building materials as well as the building ground. Possible protective measures are divided into area-related (floor structure, intermediate floors, exterior walls of cellar, foundation slab, building ground), line-related (joints, cracks, wall ducts) as well as supplementary measures (tightly closing doors, arrangement of natural cross-ventilation and vertical ventilating shafts). (BWI) [de

  12. Impact of vertical barriers on performance of pump-and-treat systems

    International Nuclear Information System (INIS)

    Russell, K.; Rabideau, A.

    1997-01-01

    Although aquifer remediation by Pump-and-treat (PAT) is widely practiced, it is generally implemented as an effective means of plume containment, rather than as an efficient means of contaminant mass removal. The use of slurry cutoff walls has been recognized as a means of improving the performance of PAT with respect to hydraulic control. As part of a study on the use of decision analysis in the design of aquifer remediation systems, the economic tradeoffs between capital costs and risk reduction were compared for several alternative PAT strategies. This work included an evaluation of the use of vertical barriers as components of PAT systems, using numerical experiments to examine the impacts of vertical barriers on PAT reliability. The results indicated that the use of vertical barriers in conjunction with PAT can significantly improve the simulated system performance, but that the magnitude of the predicted enhancement and cost-effectiveness of the barrier system are dependent on site characteristics, barrier placement, and modeling assumptions

  13. Thermal barrier coatings application in diesel engines

    Science.gov (United States)

    Fairbanks, J. W.

    1995-01-01

    Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also provide protection. Roy Kamo introduced thermal barrier coatings in his 'Adiabatic Diesel Engine' in the late 70's. Kamo's concept was to eliminate the engine block water cooling system and reduce heat losses. Roy reported significant performance improvements in his thermally insulated engine at the SAE Congress in 1982. Kamo's work stimulates major programs with insulated engines, particularly in Europe. Most of the major diesel engine manufacturers conducted some level of test with insulated combustion chamber components. They initially ran into increased fuel consumption. The German engine consortium had Prof. Woschni of the Technical Institute in Munich. Woschni conducted testing with pistons with air gaps to provide the insulation effects. Woschni indicated the hot walls of the insulated engine created a major increase in heat transfer he refers to as 'convection vive.' Woschni's work was a major factor in the abrupt curtailment of insulated diesel engine work in continental Europe. Ricardo in the UK suggested that combustion should be reoptimized for the hot-wall effects of the insulated combustion chamber and showed under a narrow range of conditions fuel economy could be improved. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the

  14. Domain wall universe in the Einstein-Born-Infeld theory

    International Nuclear Information System (INIS)

    Lee, Bum-Hoon; Lee, Wonwoo; Minamitsuji, Masato

    2009-01-01

    In this Letter, we discuss the dynamics of a domain wall universe embedded into the charged black hole spacetime of the Einstein-Born-Infeld (EBI) theory. There are four kinds of possible spacetime structures, i.e., those with no horizon, the extremal one, those with two horizons (as the Reissner-Nordstroem black hole), and those with a single horizon (as the Schwarzshild black hole). We derive the effective cosmological equations on the wall. In contrast to the previous works, we take the contribution of the electrostatic energy on the wall into account. By examining the properties of the effective potential, we find that a bounce can always happen outside the (outer) horizon. For larger masses of the black hole, the height of the barrier between the horizon and bouncing point in the effective potential becomes smaller, leading to longer time scales of bouncing process. These results are compared with those in the previous works.

  15. SprayWall, Cured-In-Placed Method for Manhole Rehabilitation

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Manholes and other underground structures commonly account for 25-30 % of infiltration and up to 70% of inflow in sanitary sewer collection systems. These will cause sewer overflow and endanger the nearby environment. SprayWall is a spray-applied, cured-in-place method of construction and is primarily used in manholes. It uses urethane material that provides excellent corrosion resistance. SprayWall is structural and can withstand ground water loads on a long-term basis.

  16. Behaviour of Masonry Walls under Horizontal Shear in Mining Areas

    Science.gov (United States)

    Kadela, Marta; Bartoszek, Marek; Fedorowicz, Jan

    2017-12-01

    The paper discusses behaviour of masonry walls constructed with small-sized elements under the effects of mining activity. It presents some mechanisms of damage occurring in such structures, its forms in real life and the behaviour of large fragments of masonry walls subjected to specific loads in FEM computational models. It offers a constitutive material model, which enables numerical analyses and monitoring of the behaviour of numerical models as regards elastic-plastic performance of the material, with consideration of its degradation. Results from the numerical analyses are discussed for isolated fragments of the wall subjected to horizontal shear, with consideration of degradation, impact of imposed vertical load as well as the effect of weakening of the wall, which was achieved by introducing openings in it, on the performance and deformation of the wall.

  17. Calcium phosphate barrier for augmentation of bone in noncontained periodontal osseous defects: a novel approach.

    Science.gov (United States)

    Chopra, Aditi; Sivaraman, Karthik; Awataramaney, Tarun K

    2014-11-01

    The aim of this technique is to augment bone in non-contained osseous deformities using a unique self-sustaining calcium phosphate barrier. Bone has the inherent ability to regenerate completely if it is provided with a fracture space or an undisturbed enclosed scaffold. A secluded environment is essential as it provides a secured, sterile and stable wound system that regenerates lost bone by a process of osteopromotion. Reconstructive techniques using bone grafts and barrier membranes utilize this principle for augmentation of deficient bony sites by providing a closed environment that promotes clot stability, graft retention, and facilitates correct cell repopulation. However, in noncontained bone defects like one walled infrabony periodontal defect or sites with horizontal bone loss, regeneration of bone still remains an unrealistic situation since osseous topography at such sites does not favor membrane stability or bone grafts retention. This case report presents a promising technique to augment bone in areas with horizontal loss. Augmentation of bone in the interdental area with horizontal bone loss was accomplished by building a contained defect using a unique self sustaining calcium phosphate cement formulation. The calcium phosphate barrier stimulates the lost cortical plates and promotes graft retention and clot stability. At 6 months, there was a significant bone fill and trabecular formation in the interdental area and reduction in tooth mobility. This promising technique could prove to be a good alternative to the conventional approaches for treating osseous deformities. Calcium phosphate is a promising barrier graft for repair of noncontained periodontal osseous defect. This technique cues both the clinicians and manufacturers to develop moldable tissue engineered constructs for osseous repair.

  18. Progressive building methods in nuclear power plant construction

    International Nuclear Information System (INIS)

    Sikura, V.

    1980-01-01

    A detailed description is given of the new prospective technologies used in the construction of the Bohunice V-1 nuclear power plant. They include the use of steel and large-area forms, the use of profile sheets as a substitute for forms, assembled raw partitions, wall shells consisting of clamped porous concrete slabs, assembled roof shells, special finish of concrete walls, bearing wall deep foundation, the use of modern building machinery for concreting, reinforcing and welding works. (M.S.)

  19. Improved interior wall detection using designated dictionaries in compressive urban sensing problems

    Science.gov (United States)

    Lagunas, Eva; Amin, Moeness G.; Ahmad, Fauzia; Nájar, Montse

    2013-05-01

    In this paper, we address sparsity-based imaging of building interior structures for through-the-wall radar imaging and urban sensing applications. The proposed approach utilizes information about common building construction practices to form an appropriate sparse representation of the building layout. With a ground based SAR system, and considering that interior walls are either parallel or perpendicular to the exterior walls, the antenna at each position would receive reflections from the walls parallel to the radar's scan direction as well as from the corners between two meeting walls. We propose a two-step approach for wall detection and localization. In the first step, a dictionary of possible wall locations is used to recover the positions of both interior and exterior walls that are parallel to the scan direction. A follow-on step uses a dictionary of possible corner reflectors to locate wall-wall junctions along the detected wall segments, thereby determining the true wall extents and detecting walls perpendicular to the scan direction. The utility of the proposed approach is demonstrated using simulated data.

  20. Long term performance of the Waterloo denitrification barrier

    International Nuclear Information System (INIS)

    Robertson, W.D.; Cherry, J.A.

    1997-01-01

    Beginning in 1991 a series of laboratory tests and small scale field trials were initiated to test the performance of an innovative permeable reactive barrier for treatment of nitrate from septic systems. The barrier promotes denitrification by providing an energy source in the form of solid organic carbon mixed into the porous media material. Advantages of the system for nitrate treatment are that the reaction is passive and in situ and it is possible to incorporate sufficient carbon mass in conveniently sized barriers to potentially provide treatment for long periods (decades) without the necessity for maintenance. However, longevity can only be demonstrated by careful long term monitoring of field installations. This paper documents four years of operating history at three small scale field trials; two where the denitrification barrier is installed as a horizontal layer positioned in the unsaturated zone below conventional septic system infiltration beds and one where the barrier is installed as a vertical wall intercepting a septic system plume at a downgradient location. The barriers have successfully attenuated 50-100% of NO - 3 -N levels of up to 170 mg/L and treatment has remained consistent over the four year period in each case, thus considerable longevity is indicated. Other field trials have demonstrated this technology to be equally effective in treating nitrogen contamination from other sources such as landfill leachate and farm field runoff

  1. Analysis, design, and constrution of a sacrificial shield wall

    International Nuclear Information System (INIS)

    Fialkow; Shah, S.B.

    1978-01-01

    The sacrificial shield wall, a cylindrical enclosure around the reactor pressure vessel (RPV), is a major component of nuclear power plants of the Boiling Water Reactor (BWR) type. A method developed for the analysis and design of such walls is described which eliminates shortcomings in methods used in current practice. The method treats the wall as a space frame of ring beams and columns and includes the skin plates as finite elements. Design loadings, load combinations, and acceptance criteria are presented. Results by this method are furnished and compared with results by an alternate method. Significant design features are described and a narrative of construction procedures is included. (Author)

  2. Monostatic ultra-wideband GPR antenna for through wall detection

    Directory of Open Access Journals (Sweden)

    Ali Jawad

    2017-01-01

    Full Text Available The aim of this paper is to present a monostatic arc-shaped ultra-wideband (UWB printed monopole antenna system with 3-16 GHz frequency bandwidth suitable for through-wall detection. Ground penetrating radar (GPR technique is used for detection with the gain of 6.2 dB achieved for the proposed antenna using defected ground structure (DGS method. To serve the purpose, a simulation experiment of through-wall detection model is constructed which consists of a monostatic antenna act as transmitter and receiver, concrete wall and human skin model. The time domain reflection of obtained result is then analysed for target detection.

  3. Measure Guideline. Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, Joseph [Building Science Corporation, Westford, MA (United States); Baker, Peter [Building Science Corporation, Westford, MA (United States)

    2015-04-09

    This measure guideline, written by the U.S. Department of Energy’s Building America team Building Science Corporation, provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ in. and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: (1) fundamental building science principles relating to the use of exterior insulation on wall assemblies; (2) design principles for tailoring this use to the specific project goals and requirements; and (3) construction detailing to increase understanding about implementing the various design elements.

  4. Construction Costs Assessment of Structural Systems for Low-Rise and Social Welfare Housing

    Directory of Open Access Journals (Sweden)

    Carrillo Julián

    2015-09-01

    Full Text Available A comparative analysis of the costs related to the construction of low-rise, low-cost and social welfare housing was carried out. The study included three of the most commonly used structural systems for low-rise housing in Latin America, such as the traditional system of confined masonry walls, concrete walls conventionally reinforced with welded-wire meshes and concrete walls reinforced with steel fiber. The cost comparison was carried out by budgets analysis, which were performed based on construction quantities, unit prices and particular items for each structural system. It was found in the study that, from an economic point of view, the systems of concrete walls reinforced with welded-wire meshes or steel fibers are more advantageous than confined masonry systems. In addition, the integral comparison of the three structural systems demonstrates that the industrialized system of steel fiber reinforced concrete walls allows obtaining greater advantages of cleaning and sustainability, faster construction, lower cost and a more attractive scenario for builders investing in such projects.

  5. Making the link: climate policy and the reform of the UK construction industry

    International Nuclear Information System (INIS)

    Sorrell, Steve

    2003-01-01

    This paper explores the barriers to energy efficiency in the construction of non-domestic buildings in the UK. The source of the barriers is argued to lie in the organisation of the construction industry, including the linear design process, the reliance on cost-based competitive tendering and the incentives placed upon different actors. The consequences include oversizing of equipment, reduced quality, neglect of whole life costs and lack of integrated design. Each of these problems can usefully be interpreted using concepts from the new institutional economics. While the barriers are well known to construction industry specialists, they are relatively neglected in the academic literature on energy policy. Furthermore, conventional policy measures such as building regulations leave these barriers largely untouched. The UK construction industry is currently undergoing a series of reforms which aim to change the relationship between different actors and to achieve improvements in product quality and productivity. While these reforms have the potential to address many of the barriers, the reform agenda makes practically no reference to sustainability. This paper argues that climate policy objectives must be integrated into the reform agenda if the UK is to begin the transition to a low carbon built environment

  6. 47 CFR 15.509 - Technical requirements for ground penetrating radars and wall imaging systems.

    Science.gov (United States)

    2010-10-01

    ..., fire fighting, emergency rescue, scientific research, commercial mining, or construction. (1) Parties... radars and wall imaging systems. 15.509 Section 15.509 Telecommunication FEDERAL COMMUNICATIONS... ground penetrating radars and wall imaging systems. (a) The UWB bandwidth of an imaging system operating...

  7. Creep behavior of soil nail walls in high plasticity index (PI) soils : technical report.

    Science.gov (United States)

    2017-04-01

    An aspect of particular concern in the Geotechnical Engineering Circular No. 7: Soil Nail Walls (i.e., the soil : nail wall manual and construction guidelines) is the creep behavior of soil nail systems in high-plasticity : clays. This research proje...

  8. Phase transition – Break down the walls

    DEFF Research Database (Denmark)

    Wandahl, Søren

    2012-01-01

    . In a popular term this problem is often called “over the wall syndrome”. The manufacturing industry has worked with this for many years, in e.g. integrated product development, concurrent engineering, supply chain management, etc. Now the construction industry needs to focus more on these crucial inter...

  9. Full-scale shear wall tests for force transfer around openings

    Science.gov (United States)

    Tom Skaggs; Borjen Yeh; Frank Lam; Douglas Rammer; James Wacker

    2010-01-01

    Wood structural panel sheathed shear walls and diaphragms are the primary lateral-load resisting elements in wood-frame construction. The historical performance of light-frame structures in North America are very good due, in part, to model building codes that are designed to preserve life safety, as well as the inherent redundancy of wood-frame construction using wood...

  10. Construction of Hydrophobic Wood Surface and Mechanical Property of Wood Cell Wall on Nanoscale Modified by Dimethyldichlorosilane

    Science.gov (United States)

    Yang, Rui; Wang, Siqun; Zhou, Dingguo; Zhang, Jie; Lan, Ping; Jia, Chong

    2018-01-01

    Dimethyldichlorosilane was used to improve the hydrophobicity of wood surface. The water contact angle of the treated wood surface increased from 85° to 143°, which indicated increased hydrophobicity. The nanomechanical properties of the wood cell wall were evaluated using a nanoindentation test to analyse the hydrophobic mechanism on the nano scale. The elastic modulus of the cell wall was significantly affected by the concentration but the influence of treatment time is insignificant. The hardness of the cell wall for treated samples was significantly affected by both treatment time and concentration. The interaction between treatment time and concentration was extremely significant for the elastic modulus of the wood cell wall.

  11. Passive-solar construction handbook

    Energy Technology Data Exchange (ETDEWEB)

    Levy, E.; Evans, D.; Gardstein, C.

    1981-02-01

    Many of the basic elements of passive solar design are reviewed. Passive solar construction is covered according to system type, each system type discussion including a general discussion of the important design and construction issues which apply to the particular system and case studies illustrating designed and built examples of the system type. The three basic types of passive solar systems discussed are direct gain, thermal storage wall, and attached sunspace. Thermal performance and construction information is presented for typical materials used in passive solar collector components, storage components, and control components. Appended are an overview of analysis methods and a technique for estimating performance. (LEW)

  12. Interaction analysis of back-to-back mechanically stabilized earth walls

    Directory of Open Access Journals (Sweden)

    Sadok Benmebarek

    2016-10-01

    Full Text Available Back-to-back mechanically stabilized earth walls (BBMSEWs are encountered in bridge approaches, ramp ways, rockfall protection systems, earth dams, levees and noise barriers. However, available design guidelines for BBMSEWs are limited and not applicable to numerical modeling when back-to-back walls interact with each other. The objective of this paper is to investigate, using PLAXIS code, the effects of the reduction in the distance between BBMSEW, the reinforcement length, the quality of backfill material and the connection of reinforcements in the middle, when the back-to-back walls are close. The results indicate that each of the BBMSEWs behaves independently if the width of the embankment between mechanically stabilized earth walls is greater than that of the active zone. This is in good agreement with the result of FHWA design guideline. However, the results show that the FHWA design guideline underestimates the lateral earth pressure when back-to-back walls interact with each other. Moreover, for closer BBMSEWs, FHWA design guideline strongly overestimates the maximum tensile force in the reinforcement. The investigation of the quality of backfill material shows that the minor increase in embankment cohesion can lead to significant reductions in both the lateral earth pressure and the maximum tensile force in geosynthetic. When the distance between the two earth walls is close to zero, the connection of reinforcement between back-to-back walls significantly improves the factor of safety.

  13. Conceptual Design and Feasibility Analyses of a Robotic System for Automated Exterior Wall Painting

    Directory of Open Access Journals (Sweden)

    Young S. Kim

    2008-11-01

    Full Text Available There are approximately 6,677,000 apartment housing units in South Korea. Exterior wall painting for such multi-dwelling apartment housings in South Korea represents a typical area to which construction automation technology can be applied for improvement in safety, productivity, quality, and cost over the conventional method. The conventional exterior wall painting is costly and labor-intensive, and it especially exposes workers to significant health and safety risks. The primary objective of this study is to design a conceptual model of an exterior wall painting robot which is applicable to apartment housing construction and maintenance, and to conduct its technical?economical feasibility analyses. In this study, a design concept using a high ladder truck is proposed as the best alternative for automation of the exterior wall painting. Conclusions made in this study show that the proposed exterior wall painting robot is technically and economically feasible, and can greatly enhance safety, productivity, and quality compared to the conventional method. Finally, it is expected that the conceptual model of the exterior wall painting robot would be efficiently used in various applications in exterior wall finishing and maintenance of other architectural and civil structures such as commercial buildings, towers, and high-rise storage tanks.

  14. Flow simulation and investigating the effects of cutoff wall on the ...

    African Journals Online (AJOL)

    Since the construction of dam is significantly important both according to economic and safety aspects, it should be carefully assessed before construction. The use of available software is one of the evaluation and behavioral investigation methods. On this basis, we have investigated the effect of cutoff wall on the seepage ...

  15. Pea border cell maturation and release involve complex cell wall structural dynamics

    DEFF Research Database (Denmark)

    Mravec, Jozef; Guo, Xiaoyuan; Hansen, Aleksander Riise

    2017-01-01

    The adhesion of plant cells is vital for support and protection of the plant body and is maintained by a variety of molecular associations between cell wall components. In some specialized cases though, plant cells are programmed to detach and root cap-derived border cells are examples of this....... Border cells (in some species known as border-like cells) provide an expendable barrier between roots and the environment. Their maturation and release is an important but poorly characterized cell separation event. To gain a deeper insight into the complex cellular dynamics underlying this process, we...... undertook a systematic, detailed analysis of pea (Pisum sativum) root tip cell walls. Our study included immuno-carbohydrate microarray profiling, monosaccharide composition determination, Fourier-transformed infrared microspectroscopy (FT-IR), quantitative RT-PCR of cell wall biosynthetic genes, analysis...

  16. Recent experimental progress in the TMX-U thermal barrier tandem mirror experiment

    International Nuclear Information System (INIS)

    Turner, W.C.; Allen, S.L.; Casper, T.A.

    1984-01-01

    Recent experiments on the TMX-U thermal barrier device at LLNL have achieved the end plugging of axial ion losses up to a central cell density of n/sub c/ = 2 x 10 12 cm. During these tests, the axial potential profile characteristic of a thermal barrier has been measured experimentally, indicating an ion-confining potential greater than 1.5 kV and a potential depression of 0.45 kV in the barrier region. The average beta of hot electrons in the thermal barrier has been increased to 15% and appears limited only by classical scattering and ECRH pulse duration. Furthermore, deuterium ions in the central cell have been heated with ICRF to an average energy of 1.5 keV, with a heating efficiency of 40%. During strong end plugging, the axial ion confinement time reached 50 to 100 ms while the nonambipolar radial ion confinement time was 5 to 15 ms - independent of end plugging. Radial ion confinement time exceeding 100 ms has been attained on shots without end plugging. Plates, floated electrically on the end walls, have increased the radial ion confinement time by a factor of 1.8. Further improvement in the central cell density during end plugging can be expected by increasing the ICRF, improving the central cell vacuum conditions and beam heating efficiency, and increasing the radial extent of the potential control plates on the end walls

  17. Surface barrier research at the Hanford Site

    International Nuclear Information System (INIS)

    Gee, G.W.; Ward, A.L.; Fayer, M.J.

    1997-01-01

    At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford

  18. Observations on out-of-plane behaviour of URM walls in buildings with RC slabs

    OpenAIRE

    Tondelli, Marco; Beyer, Katrin

    2014-01-01

    In Switzerland many new residential buildings are constructed as unreinforced masonry (URM) structures or as mixed structures where URM walls are coupled with reinforced concrete (RC) walls by RC slabs. At present the boundary conditions of URM walls subjected to out-of-plane accelerations are still not well quantified. In the framework of a large research activity on RC-URM wall structures a shake-table test on a four-storey mixed structure was performed. The test specimen, which was built a...

  19. Ultrastructural studies on the blood-brain barrier. Mainly as to changes in the permeability of cerebral capillary walls induced by experimental x-ray irradiation and the effect of glucocorticoid on such changes

    Energy Technology Data Exchange (ETDEWEB)

    Ichitsubo, H [Tokyo Medical Coll. (Japan)

    1977-03-01

    In the present study, an ultrastructural examination was made of the role of capillary endothelial cells of the brain which is one of the constituent factors of the blood-brain barrier. In normal cerebral capillaries, both endothelial cells and the basement membrane were demonstrated to be not crossed by a tracer (horseradish peroxidase) even in 60 minutes after its intravenous administration, thus suggesting the blood-brain barrier effect. Author investigated changes in the permeability of cerebral capillary walls induced by experimental brain irradiation and the effect of glucocorticoid on such changes. On forty-eight hours following an appropriate irradiation a marked brain edema was developed; under such circumstances when the tracer was injected intravenously, on 60 minutes thereafter the tracer was demonstrated to be transferred into the neutral tissue, and this was interpreted as indicating that capillary hyperpermeability was induced. These findings were suggested that the mechanism of capillary hyperpermeability might not be based on the passage of a tight junction of the cells of capillary wall but rather on account of activated active transport via an increased number of pinocytotic vesicles. The mechanism of increase of pinocytotic vesicle appeared to be resulting from a breakdown of the controlling system of pinocytotic vesicle production. However, the existence of this controlling system is still speculative. Pre-and post-irradiation administration of glucocorticoid proved to be effective in the prevention of irradiation-induced hyperpermeability of cerebral capillaries, and to be indicating the possible usefulness of the drug for the maintenance or repair of the aforementioned system.

  20. The Insulation Vacuum Barrier for the Large Hadron Collider (LHC) Magnet Cryostats

    CERN Document Server

    Castoldi, M; Parma, Vittorio; Skoczen, Blazej; Trilhe, P

    2000-01-01

    The sectorisation of the insulation vacuum of the LHC magnet cryostats, housing the superconducting magnets, which operate in a 1.9 K superfluid helium bath, is achieved by means of vacuum barriers. Each vacuum barrier is a leak-tight austenitic stainless steel thin-wall structure, mainly composed of large diameter (between 0.6 m and 0.9 m) bellows and concentric corrugated cylinders. It is mounted in the Short Straight Section (SSS) [1], between the magnet helium enclosure and the vacuum vessel. This paper presents the design of the vacuum barrier, concentrating mostly on its expected thermal performance, to fulfil the tight LHC heat in-leak budgets. Pressure and leak test results, confirming the mechanical design of two prototypes manufactured in industry, and the preparation of one of these vacuum barriers for cryogenic testing in an SSS prototype, are also mentioned.

  1. Bioactive surface modifications on inner walls of poly-tetra-fluoro-ethylene tubes using dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Ki [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Heat Treatment and Surface Engineering R and D Group, Korea Institute of Industrial Technology, Incheon 406-840 (Korea, Republic of); Park, Daewon; Kim, Hoonbae [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Hyerim; Park, Heonyong [Department of Molecular Biology, Dankook University, Yongin 448-701 (Korea, Republic of); Kim, Hong Ja [Department of Internal Medicine, Dankook University, Cheonan 330-714 (Korea, Republic of); Jung, Donggeun, E-mail: djung@skku.ac.kr [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-03-01

    Graphical abstract: - Highlights: • The surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts. • Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment using micro plasma discharge. - Abstract: Bioactive surface modification can be used in a variety of medical polymeric materials in the fields of biochips and biosensors, artificial membranes, and vascular grafts. In this study, the surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts, which are made of biocompatible material for the human body in the medical field. Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment on the PFTE surface using micro plasma discharge. Micro plasma was generated by a medium-frequency alternating current high-voltage generator. The preliminary modification of PTFE was conducted by a plasma of hydrogen and argon gases. The hydrocarbon thin film was deposited on modified PTFE with a mixture of acetylene and argon gases. The reactive plasma treatment using oxygen plasma was done to give biocompatible functionality to the inner wall surface. The hydrophobic surface of bare PTFE is made hydrophilic by the reactive plasma treatment due to the formation of carbonyl groups on the surface. The reactive treatment could lead to improved attachment of smooth muscle cells (SMCs) on the modified PTFE tubing. Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurement were used for the analysis of the surface modification. The SMC-attached PTFE tube developed will be applicable to in vitro human vasculature

  2. Bioactive surface modifications on inner walls of poly-tetra-fluoro-ethylene tubes using dielectric barrier discharge

    International Nuclear Information System (INIS)

    Cho, Yong Ki; Park, Daewon; Kim, Hoonbae; Lee, Hyerim; Park, Heonyong; Kim, Hong Ja; Jung, Donggeun

    2014-01-01

    Graphical abstract: - Highlights: • The surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts. • Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment using micro plasma discharge. - Abstract: Bioactive surface modification can be used in a variety of medical polymeric materials in the fields of biochips and biosensors, artificial membranes, and vascular grafts. In this study, the surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts, which are made of biocompatible material for the human body in the medical field. Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment on the PFTE surface using micro plasma discharge. Micro plasma was generated by a medium-frequency alternating current high-voltage generator. The preliminary modification of PTFE was conducted by a plasma of hydrogen and argon gases. The hydrocarbon thin film was deposited on modified PTFE with a mixture of acetylene and argon gases. The reactive plasma treatment using oxygen plasma was done to give biocompatible functionality to the inner wall surface. The hydrophobic surface of bare PTFE is made hydrophilic by the reactive plasma treatment due to the formation of carbonyl groups on the surface. The reactive treatment could lead to improved attachment of smooth muscle cells (SMCs) on the modified PTFE tubing. Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurement were used for the analysis of the surface modification. The SMC-attached PTFE tube developed will be applicable to in vitro human vasculature

  3. Electric-field control of magnetic domain-wall velocity in ultrathin cobalt with perpendicular magnetization.

    Science.gov (United States)

    Chiba, D; Kawaguchi, M; Fukami, S; Ishiwata, N; Shimamura, K; Kobayashi, K; Ono, T

    2012-06-06

    Controlling the displacement of a magnetic domain wall is potentially useful for information processing in magnetic non-volatile memories and logic devices. A magnetic domain wall can be moved by applying an external magnetic field and/or electric current, and its velocity depends on their magnitudes. Here we show that the applying an electric field can change the velocity of a magnetic domain wall significantly. A field-effect device, consisting of a top-gate electrode, a dielectric insulator layer, and a wire-shaped ferromagnetic Co/Pt thin layer with perpendicular anisotropy, was used to observe it in a finite magnetic field. We found that the application of the electric fields in the range of ± 2-3 MV cm(-1) can change the magnetic domain wall velocity in its creep regime (10(6)-10(3) m s(-1)) by more than an order of magnitude. This significant change is due to electrical modulation of the energy barrier for the magnetic domain wall motion.

  4. Study on the saturating and swelling behavior of an engineering bentonite barrier using a test model

    International Nuclear Information System (INIS)

    Nakajima, Makoto; Kobayashi, Ichizo; Toida, Masaru; Fujisaki, Katsutoshi

    2007-01-01

    The conceptual design of a disposal facility with additional buffer depth for radioactive waste is mainly constituted from the multi-barrier system that is constructed around the waste form so that it prevents radionuclide transfer to the biosphere. The engineered bentonite barrier is one of the elements of the multi-barrier system and is constructed with homogeneous bentonite-containing material compacted to a high density so that there are no voids. Due to the swelling characteristics of the bentonite material, the self-sealing function which is an important function of the bentonite barrier can work, but at the same time it mechanically affects the neighboring structures. Therefore, an experimental study was implemented in order to evaluate the mechanical effect of the bentonite swelling behavior throughout the construction, emplacement operations and closure re-saturation phase. In this article, the results of swelling tests to obtain the mechanical properties of the bentonite and three types of test model experiments performed for the event observations in the different saturation processes are described. As a result, the effects of a seepage pattern of ground water and a variation in the density produced by construction on the swelling pressure distribution of the bentonite barrier could be reproduced and validated. It is thought that they will be important events when ground water permeates the bentonite layer of a multiple barrier system. (author)

  5. Contextualizing Territories in Gvc Supplier Nodes to Understand Chain Entry Barriers

    DEFF Research Database (Denmark)

    Thomsen, Lotte; Kamau, Paul; McCormick, Dorothy

    This paper deals with entry barriers for developing country suppliers to global value chains (GVCs). It is based on a study of food processing firms in Kenya undertaken between 2012 and 2014. The paper focuses on how entry barriers to GVCs are sometimes constructed within supplier countries, and ...

  6. Frequency Characteristics of Double-Walled Carbon Nanotube Resonator with Different Length

    Directory of Open Access Journals (Sweden)

    Jun-Ha LEE

    2016-05-01

    Full Text Available In this paper, we have conducted classical molecular dynamics simulations for DWCNTs of various wall lengths to investigate their use as ultrahigh frequency nano-mechanical resonators. We sought to determine the variations in the frequency of these resonators according to changes in the DWCNT wall lengths. For a double-walled carbon nanotube resonator with a shorter inner nanotube, the shorter inner nanotube can be considered to be a flexible core, and thus, the length influences the fundamental frequency. In this paper, we analyze the variation in frequency of ultra-high frequency nano-mechnical resonators constructed from DWCNTs with different wall lengths.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.12951

  7. Vertical Equilibrium of Sheet Pile Walls with Emphasis on Toe Capacity and Plugging

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Augustesen, Anders Hust; Nielsen, Benjaminn Nordahl

    Constructions including retaining walls are normally established in areas where it is impossible to conduct an excavation with inclined sides. Due to large excavation depths and due to restrictions on the deformations of the wall, it is often necessary to anchor the wall. The limited space makes...... at the pile toe to fulfil vertical equilibrium. The paper describes a case study of sheet pile walls in Aalborg Clay, and the amount of loads transferred as point loads at the pile toe for free and anchored walls is estimated. A parametric study is made for the free wall with regards to the height...... and the roughness of the wall. Due to limitations of the calculation method, the study of the anchored wall only includes variation of the roughness. For the case study, it is found that the vertical equilibrium is fulfilled for the considered free wall. An anchored wall needs a plug forming at the pile toe...

  8. Green Construction in Building Renovation

    Directory of Open Access Journals (Sweden)

    Ksit Barbara

    2016-06-01

    Full Text Available Modern materials and construction solutions draw more and more attention to ecology and building certification. Among the criteria appearing in revitalization, an important element is bringing plants back into heavily urbanized areas. In its natural form, this is not possible to carry out everywhere, often requiring large amounts of space. Nowadays, however, there are a number of green roofs and green wall systems, allowing “greener” construction without making significant changes in the urban environment.

  9. Permanent isolation surface barrier development plan

    International Nuclear Information System (INIS)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no open-quotes provenclose quotes long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems

  10. Permanent isolation surface barrier development plan

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

  11. Impenetrable Barriers in Phase-Space

    International Nuclear Information System (INIS)

    Wiggins, S.; Wiesenfeld, L.; Jaffe, C.; Uzer, T.

    2001-01-01

    Dynamical systems theory is used to construct a general phase-space version of transition state theory. Special multidimensional separatrices are found which act as impenetrable barriers in phase-space between reacting and nonreacting trajectories. The elusive momentum-dependent transition state between reactants and products is thereby characterized. A practical algorithm is presented and applied to a strongly coupled Hamiltonian

  12. Seismic Performance and Modeling of Reinforced Concrete and Post-Tensioned Precast Concrete Shear Walls

    OpenAIRE

    Tanyeri, Ahmet Can

    2014-01-01

    Past earthquakes have shown examples of unsatisfactory performance of buildings using reinforced concrete structural walls as the primary lateral-force-resisting system. In the 1994 Northridge earthquake, examples can be found where walls possessed too much overstrength, leading to unintended failure of collectors and floor systems, including precast and post-tensioned construction. In the 2010 Maule Chile earthquake, many structural wall buildings sustained severe damage. Although Chilean de...

  13. Development of pipe wall thinning prediction software 'FALSET'

    International Nuclear Information System (INIS)

    Yoneda, Kimitoshi; Morita, Ryo; Inada, Fumio; Fujiwara, Kazutoshi

    2012-01-01

    Pipe wall thinning in power plants has been managed for maintaining plant integrity and safety with great importance. The target thinning phenomena are Flow Accelerated Corrosion (FAC) and Liquid Droplet Impingement Erosion (LDI). At present, the management is based on thinning rate and residual lifetime evaluation using pipe wall thickness measurement results. For the future, more safety and improvement in the management is required, and in this sense, prediction method of wall thinning is willing to be introduced. Therefore, prediction model of FAC and LDI have been constructed in CRIEPI, and to utilize these models to actual plant piping management easily, prediction software 'FALSET' is developed. FALSET has equipped with essential function for pipe wall thinning management in power plants, as follows; (1) Information and condition input of plant piping system and its component, (2) Wall thinning rate evaluation with CRIEPI's FAC/LDI prediction model, (3) Loading of wall thickness measurement data files and graphics of data trend, (4) Residual lifetime evaluation considering both measured and predicted thinning rate, (5) Statistical process and graphics of thinning rate and residual lifetime for multi-piping systems. With further verification and improvement of each function, there will be a perspective for this FALSET to be utilized as a management tool in power plants. (author)

  14. Ebb-tidal delta morphology in response to a storm surge barrier

    NARCIS (Netherlands)

    Eelkema, M.; Wang, Z.B.; Hibma, A.

    2012-01-01

    The Eastern Scheldt ebb-tidal delta morphology has been adapting for the past 25 years in response to the construction of the Eastern Scheldt storm-surge barrier in 1986. As a result of the barrier, there has been a decrease in tidal amplitudes, volumes, and average flow velocities, and there is

  15. A first wall material probe manipulator for the 'TEXTOR' tokamak

    International Nuclear Information System (INIS)

    Marmy, P.; Stiefel, U.

    1984-04-01

    Textor is a technology oriented tokamak of Euratom at the Kernforschungsanlage Juelich (KFA). Switzerland participates in its experimental program within the framework of the IEA agreement on Plasma Wall Interaction. A major task of EIR consists in the layout, construction and fabrication of a manipulator for the remote handling of up to 240 specimen candidate first wall materials. This operation has to be done without breaking the ultra high vacuum (UHV) and with wall temperatures up to 300 0 C. A great number of preexperiments involving different materials had to be carried out; the understanding of the tribology in ultra high vacuum could be improved. (Auth.)

  16. Wall roughness effects on flow and scouring in curved channels with gravel bed

    OpenAIRE

    Hersberger, Daniel S.

    2002-01-01

    Wall roughness effects on flow and scouring in curved channels with gravel bed In the narrow valleys in Alpine regions, rivers frequently flow across constructed zones, passing through villages and cities. Due to limited space, the protection from high floods often needs to be ensured by protection walls. During floods, these protection walls may be endangered by scour phenomena, especially if they are located in bends. In the past, the potential danger of underscoured structures was reduced ...

  17. Construction of concrete hot cells; requirements for shielding windows for concrete walls with different densities

    International Nuclear Information System (INIS)

    1987-10-01

    The shielding windows form part of the basic equipment of hot cells for remote handling, as defined in standard DIN 25 420 part 1. The draft standard in hand is intended to specify the design and manufacture requirements, especially with regard to main dimensions, sight quality, shielding effects, and radiation resistance. The standard refers to three types of shielding window with surface area design (product of density and wall thickness) corresponding to concrete walls of the densities 2.4, 3.4, and 4.0 g/cm 3 . The windows fit to three types of concrete of common usage, and the design is made for Co-60 radiation, with attenuation factors of about 10 4 , 10 6 , or 10 7 . For concrete walls with densities between these data, a shielding window suitable to the next higher density data is to be chosen. (orig./HP) [de

  18. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement.

    Science.gov (United States)

    Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun

    2014-08-19

    Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied.

  19. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement

    Directory of Open Access Journals (Sweden)

    Wanlin Cao

    2014-08-01

    Full Text Available Recycled concrete brick (RCB is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied.

  20. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement

    Science.gov (United States)

    Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun

    2014-01-01

    Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied. PMID:28788170

  1. Drywall plates evaluation as protection barriers in dental X-rays and mammography facilities; Evaluacion de placas de drywall como barreras de proteccion en instalaciones de rayos X dental y mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Guevara R, V. Y.; Romero C, N. [Empresa QC DOSE S. A. C., Av. Tomas Marsano 1915, Surquillo, Lima 34 (Peru); Berrocal T, M., E-mail: vguevara@qcdose.com [Universidad Nacional Mayor de San Marcos, C. German Amezaga 375, Edif. Jorge Basadre, Ciudad Universitaria, Lima 1 (Peru)

    2014-08-15

    In the dental X-rays and mammography facilities, usually lead shielded walls as protective barriers are used. Lead is a good attenuator for X-rays, but has toxic properties and its cost is high. Mammography equipment s emit low-energy photons in the range of 25 keV to 35 keV, on current computers; the primary radiation beam is intercepted by the image receptor. Peri apical dental equipment s emit photons in the range of 50 to 90 keV, their filtration is fixed. These devices emit a collimated beam whose diameter is slightly larger than the diagonal dimension of a standard film of dental X-rays. When a dental x-ray is performed, the radiation beam is partially attenuated by the patient. Drywall is a material consisting of plasterboard between two cardboard layers, being its components gypsum and cellulose generally. It is used in construction for execution of interior walls, ceilings and wall coverings, could also serve as a replacement for lead as well as other materials. In this paper three drywall prototypes (Giplac), formed with 02, 04 and 06 drywall layers (13, 16 and 20 cm of thickness respectively) were tested as barriers against primary and secondary X-ray radiation that come from dental and mammography equipment s. The results show that the drywall prototype, 02 layers, efficiently attenuates the secondary radiation beam produced by conventional mammography equipment. And the prototype 04 and 06 layers, efficiently attenuates the primary radiation beam produced by peri apical dental equipment. (author)

  2. Conception of thermonuclear reactor with a shielding layer of the first wall

    International Nuclear Information System (INIS)

    Marin, S.V.

    1979-01-01

    Considered is the way of the shielding of the first wall of a thermonuclear reactor by the layer of ISSEC (Internal spectral shifter and Energy Converter). It is a constructive non-power element placed between a plasma and the first wall, and intended for the softening of the spectrum and intensity reduction of particle fluxes falling on the first wall. Results of neutron-physical calculations of the UWMAK-type reactor blanket (in the S 4 -P 3 approximation) are presented. While comparing five materials (C, Mo, Nb, V,W) by the rate of radiation damage formation, gas production, radioactivity level and energy output in the blanket with the 316 stainless steel first wall, it is obvious that the conception of ISSEC permits to prolong the service period of the first wall. Construction elements should be then in the same irradiation conditions as those in fast reactors. Molybdenum has been taken as the best ISSEC material. It reduces the number of displaced atoms of the first wall by 20% and decreases helium production by about 100%, increases energy output in the blanket by 15-18%. However, graphite is advantageous, while comparing it to molybdenum in values of residual energy output, radioactivity level, costs and manufacture simplicity. One problem stays unsolved, which is connected with chemical sputtering of graphite at the formation of C 2 H 2 in the high temperature range. So it is hard to prefer any material now

  3. Development of fusion first-wall radiation damage facilities

    International Nuclear Information System (INIS)

    McElroy, R.J.; Atkins, T.

    1986-11-01

    The report describes work performed on the development of fusion-reactor first-wall simulation facilities on the Variable Energy Cyclotron, at Harwell, United Kingdom. Two irradiation facilities have been constructed: i) a device for helium and hydrogen filling up to 1000 ppm for post-irradiation mechanical properties studies, and ii) a helium implantation and damage facility for simultaneous injection of helium and radiation damage into a specimen under stress. These facilities are now fully commissioned and are available for investigations of first-wall radiation damage and for intercorrelation of fission- and fusion -reactor materials behaviour. (U.K.)

  4. Performance of Screen Grid Insulating Concrete Form Walls under Combined In-Plane Vertical and Lateral Loads

    KAUST Repository

    Abdel Mooty, Mohamed

    2010-12-01

    Insulating Concrete Forms (ICF) walls generally comprise two layers of Expanded Polystyrene (EPS), steel reinforcement is placed in the center between the two layers and concrete is poured to fill the gap between those two layers. ICF\\'s have many advantages over traditional methods of wall construction such as reduced construction time, noise reduction, strength enhancement, energy efficiency, and compatibility with any inside or outside surface finish. The focus of this study is the Screen Grid ICF wall system consisting of a number of beams and columns forming a concrete mesh. The performance of ICF wall systems under lateral loads simulating seismic effect is experimentally evaluated in this paper. This work addresses the effect of the different design parameters on the wall behavior under seismic simulated loads. This includes different steel reinforcement ratio, various reinforcement distribution, wall aspect ratios, different openings sizes for windows and doors, as well as different spacing of the grid elements of the screen grid wall. Ten full scale wall specimens were tested where the effects of the various parameters on wall behavior in terms of lateral load capacity, lateral displacement, and modes of failure are presented. The test results are stored to be used for further analysis and calibration of numerical models developed for this study. © (2011) Trans Tech Publications.

  5. LB03.04: SPHYGMOMANOMETER CUFF CONSTRUCTION AND MATERIALS AFFECT TRANSMISSION OF PRESSURE FROM CUFF TO ARTERIAL WALL. FINITE ELEMENT ANALYSIS OF HUMAN PRESSURE MEASUREMENTS AND DICOM DATA.

    Science.gov (United States)

    Lewis, P; Naqvi, S; Mandal, P; Potluri, P

    2015-06-01

    Sphygmomanometer cuff pressure during deflation is assumed to equal systolic arterial pressure at the point of resumption of flow. Previous studies demonstrated that pressure decreases with increasing depth of soft tissues whilst visco-elastic characteristics of the arm tissue cause spatial and temporal variation in pressure magnitude. These generally used non-anatomical axisymmetrical arm simulations without incorporating arterial pressure variation. We used data from a volunteer's Magnetic Resonance (MR) arm scan and investigated the effect of variations in cuff materials and construction on the simulated transmission of pressure from under the cuff to the arterial wall under sinusoidal flow conditions. Pressure was measured under 8 different cuffs using Oxford Pressure Monitor Sensors placed at 90 degrees around the mid upper arm of a healthy male. Each cuff was inflated 3 times to 155 mmHg and then deflated to zero with 90 seconds between inflations. Young's modulus, flexural rigidity and thickness of each cuff was measured.Using DICOM data from the MR scan of the arm, a 3D model was derived using ScanIP and imported into Abaqus for Finite Element Analysis (FEA). Published mechanical properties of arm tissues and geometric non-linearity were assumed. The measured sub-cuff pressures were applied to the simulated arm and pressure was calculated around the brachial arterial wall. which was loaded with a sinusoidal pressure of 125/85 mmHg. FEA estimates of pressure around the brachial artery cuffs varied by up to 27 mmHg SBP and 17 mmHg DBP with different cuffs. Pressures within the cuffs varied up to 27 mmHg. Pressure transmission from the cuff to the arterial surface achieved a 95% transmission ratio with one rubber-bladdered cuff but varied between 76 and 88% for the others. Non-uniform pressure distribution around the arterial wall was strongly related to cuff fabric elastic modulus. Identical size cuffs with a separate rubber bladder produced peri

  6. Construction of hydroelectric project generation: Focuses of the option value

    International Nuclear Information System (INIS)

    Villegas P, Clara Ines

    2002-01-01

    Work present work aims at the development of an analysis, that using the option value approach allows finding the optimal moment (from the environmental point of view), for the construction of an electrical project generation in a zone with determined environmental characteristics. The construction of the project, constitutes an irreversible decision and with uncertainty associated. The evolution of the environmental damage of the zone can be attracting through the variable C of environmental damage. The analysis developed here allows the characterization of a rule (or a barrier of environmental damage called C, which determines when, is optimal to construct the generation project or to conserve the ecosystems of the zone of location. Over this barrier, the construction of the project becomes optimal and below her the conservation of the ecosystems of the zone is privileged

  7. Green Construction in Building Renovation

    Science.gov (United States)

    Ksit, Barbara; Majcherek, Michał

    2016-06-01

    Modern materials and construction solutions draw more and more attention to ecology and building certification. Among the criteria appearing in revitalization, an important element is bringing plants back into heavily urbanized areas. In its natural form, this is not possible to carry out everywhere, often requiring large amounts of space. Nowadays, however, there are a number of green roofs and green wall systems, allowing "greener" construction without making significant changes in the urban environment. The article includes a presentation and analysis of selected solutions of biological surfaces known as green roofs and green walls, specifying various solutions and their most important features. The case study focuses primarily on material and design solutions, as well as the potential benefits, risks and limitations in their use. Plants structures on the surfaces of vertical and horizontal partitions continue to be a very interesting alternative to take into account when applying for grants, such as LEED or BREEAM certificates.

  8. Tornado missile impact study

    International Nuclear Information System (INIS)

    McDonald, J.R.

    1991-01-01

    UCRL-15910 specifies wind and tornado missiles for moderate- and high-hazard DOE facilities. Wall-barrier specimens have been tested at the Tornado Missile Impact Facility at Texas Tech University. The facility has an air-activated tornado missile cannon capable of firing 2x4 timber planks weighing 12 lb at speeds up to 150 mph and 3-in-diameter steel pipes weighing 75 lb at speeds to 7 5 mph. Wall barriers tested to date include reinforced concrete walls from 4-in. to 10-in. thick; 8-in. and 12-in. walls of reinforced concrete masonry units (CMU); two other masonry wall configurations consisting of an 8-in. CMU with a 4-in. clay-brick veneer and a 10-in. composite wall with two wythes of 4-in. clay brick. The impact test series is designed to determine the impact speed that will produce backface spall of each wall barrier. A set of 15 wall sections has been constructed and tested at this time. Preliminary finding suggest that all cells of CMU walls must be grouted to prevent missile penetration. Walls recommended in the workshop on UCRL-15910 provide acceptable protection if cracking can be accepted

  9. TMX-U thermal-barrier experiments

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Barter, J.D.

    1988-01-01

    This review of thermal-barrier experiments in the Tandem Mirror Experiment Upgrade (TMX-U) describes our progress at Lawrence Livermore National Laboratory in plasma confinement and central-cell heating. Thermal barriers in TMX-U improved axial confinement by two orders of magnitude over a limited range of densities, compared with confinement in single-cell mirrors at the same ion temperature. Our study shows that central-cell radial nonambipolar confinement scales as neoclassical theory and can be eliminated by floating the end walls. Radial ambipolar losses can also be measured and reduced. The electron energy balance is improved in tandem mirrors to near classical, resulting in T/sub e/ up to 0.28 keV. Electron cyclotron heating (ECH) efficiencies up to 42 percent, with low levels of electron microinstability, were achieved when hot electrons in the thermal barrier were heated to average betas as large as 15 percent. The hot-electron distribution is measured from X rays and is modeled by a Fokker-Planck code that includes heating from cavity radio-frequency (RF) fields. Neutral-beam injection in the central cell created average ion betas up to 5 percent with radial profiles of hot ions that are modeled accurately by a radial Fokker-Planck code. Gas fueling between two fundamental ion cyclotron heating (ICH) resonances resulted in symmetrical heating of passing ions toward both ends

  10. Safety-related concrete structure design and construction of Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    Morishita, Hideki; Munakata, Yoshinari; Togashi, Akihito

    2003-01-01

    The Rokkasho Reprocessing Plant of the Japan Nuclear Fuel Co. Ltd., is a facility to reprocess remained uranium without firing and newly formed plutonium contained in spent fuels used at the nuclear power stations, to produce fuels to be repeatedly used. Constructions in this facility has some characteristics shown as follows: 1) radiation shielding and seismic isolated functions like those at the nuclear power plants, 2) reduction of wall thickness based on partially using heavy concrete at walls required for radiation shielding, 3) protective design against fly-coming matters such as aircrafts, 4) construction period reduction based on winter construction and large scale block engineering. Here were described characteristics of designs on radiation shielding, seismic isolated and fly-coming matters protection construction engineering and quality control on concrete. (G.K.)

  11. Tank wall thinning -- Process and programs

    International Nuclear Information System (INIS)

    Greer, S.D.; McBrine, W.J.

    1994-01-01

    In-service thinning of tank walls has occurred in the power industry and can pose a significant risk to plant safety and dependability. Appropriate respect for the energy stored in a high-pressure drain tank warrants a careful consideration of this possibility and appropriate action in order to assure the adequate safety margins against leakage or rupture. Although it has not proven to be a widespread problem, several cases of wall thinning and at least one recent tank rupture has highlighted this issue in recent years, particularly in nuclear power plants. However, the problem is not new or unique to the nuclear power industry. Severe wall thinning in deaerator tanks has been frequently identified at fossil-fueled power plants. There are many mechanisms which can contribute to tank wall thinning. Considerations for a specific tank are dictated by the system operating conditions, tank geometry, and construction material. Thinning mechanisms which have been identified include: Erosion/Corrosion Impingement Erosion Cavitation Erosion General Corrosion Galvanic Corrosion Microbial-induced Corrosion of course there are many other possible types of material degradation, many of which are characterized by pitting and cracking. This paper specifically addresses wall thinning induced by Erosion/Corrosion (also called Flow-Accelerated Corrosion) and Impingement Erosion of tanks in a power plant steam cycle. Many of the considerations presented are applicable to other types of vessels, such as moisture separators and heat exchangers

  12. Passive solar construction handbook

    Energy Technology Data Exchange (ETDEWEB)

    Levy, E.; Evans, D.; Gardstein, C.

    1981-08-01

    Many of the basic elements of passive solar design are reviewed. The unique design constraints presented in passive homes are introduced and many of the salient issues influencing design decisions are described briefly. Passive solar construction is described for each passive system type: direct gain, thermal storage wall, attached sunspace, thermal storage roof, and convective loop. For each system type, important design and construction issues are discussed and case studies illustrating designed and built examples of the system type are presented. Construction details are given and construction and thermal performance information is given for the materials used in collector components, storage components, and control components. Included are glazing materials, framing systems, caulking and sealants, concrete masonry, concrete, brick, shading, reflectors, and insulators. The Load Collector Ratio method for estimating passive system performance is appended, and other analysis methods are briefly summarized. (LEW)

  13. Theoretical domains framework to assess barriers to change for planning health care quality interventions: a systematic literature review.

    Science.gov (United States)

    Mosavianpour, Mirkaber; Sarmast, Hamideh Helen; Kissoon, Niranjan; Collet, Jean-Paul

    2016-01-01

    Theoretical domains framework (TDF) provides an integrative model for assessing barriers to behavioral changes in order to suggest interventions for improvement in behavior and ultimately outcomes. However, there are other tools that are used to assess barriers. The objective of this study is to determine the degree of concordance between domains and constructs identified in two versions of the TDF including original (2005) and refined version (2012) and independent studies of other tools. We searched six databases for articles that studied barriers to health-related behavior changes of health care professionals or the general public. We reviewed quantitative papers published in English which included their questionnaires in the article. A table including the TDF domains of both original and refined versions and related constructs was developed to serve as a reference to describe the barriers assessed in the independent studies; descriptive statistics were used to express the results. Out of 552 papers retrieved, 50 were eligible to review. The barrier domains explored in these articles belonged to two to eleven domains of the refined TDF. Eighteen articles (36%) used constructs outside of the refined version. The spectrum of barrier constructs of the original TDF was broader and could meet the domains studied in 48 studies (96%). Barriers in domains of "environmental context and resources", "beliefs about consequences", and "social influences" were the most frequently explored in 42 (84%), 37 (74%), and 33 (66%) of the 50 articles, respectively. Both refined and original TDFs cataloged barriers measured by the other studies that did not use TDF as their framework. However, the original version of TDF explored a broader spectrum of barriers than the refined version. From this perspective, the original version of the TDF seems to be a more comprehensive tool for assessing barriers in practice.

  14. DNA nanovehicles and the biological barriers

    DEFF Research Database (Denmark)

    Okholm, Anders Hauge; Kjems, Jørgen

    2016-01-01

    DNA is emerging as a smart material to construct nanovehicles for targeted drug delivery. The programmability of Watson-Crick base paring enables construction of defined and dynamic DNA nanostructures of almost arbitrary shape and DNA can readily be functionalized with a variety of molecular...... be overcome. Here, we highlight recent strategies for DNA nanostructures in drug delivery, DNA nanovehicles, to facilitate targeting and crossing of the biological barriers. In light of this, we discuss future solutions and challenges for DNA nanovehicles to unravel their great potential to facilitate...

  15. Plant cell walls throughout evolution: towards a molecular understanding of their design principles.

    Science.gov (United States)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-01-01

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche, which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  16. Plant cell walls throughout evolution: towards a molecular understanding of their design principles

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-02-16

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche,which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  17. Phenomenology of wall-bounded Newtonian turbulence.

    Science.gov (United States)

    L'vov, Victor S; Pomyalov, Anna; Procaccia, Itamar; Zilitinkevich, Sergej S

    2006-01-01

    We construct a simple analytic model for wall-bounded turbulence, containing only four adjustable parameters. Two of these parameters are responsible for the viscous dissipation of the components of the Reynolds stress tensor. The other two parameters control the nonlinear relaxation of these objects. The model offers an analytic description of the profiles of the mean velocity and the correlation functions of velocity fluctuations in the entire boundary region, from the viscous sublayer, through the buffer layer, and further into the log-law turbulent region. In particular, the model predicts a very simple distribution of the turbulent kinetic energy in the log-law region between the velocity components: the streamwise component contains a half of the total energy whereas the wall-normal and cross-stream components contain a quarter each. In addition, the model predicts a very simple relation between the von Kármán slope k and the turbulent velocity in the log-law region v+ (in wall units): v+=6k. These predictions are in excellent agreement with direct numerical simulation data and with recent laboratory experiments.

  18. Construction safety in DOE. Part 2, Students guide

    Energy Technology Data Exchange (ETDEWEB)

    Handwerk, E.C.

    1993-08-01

    This report is the second part of a compilation of safety standards for construction activities on DOE facilities. This report covers the following areas: floor and wall openings; cranes, derricks, hoists, elevators, and conveyors; motor vehicles, mechanized equipment, and marine operations; excavations; concrete and masonry construction; steel erection; underground construction, caisson, cofferdams, and compressed air; demolition; blasting and the use of explosives; power transmission and distribution; rollover protective structures, overhead protection; and ladders.

  19. Domain walls and the C P anomaly in softly broken supersymmetric QCD

    Science.gov (United States)

    Draper, Patrick

    2018-04-01

    In ordinary QCD with light, degenerate, fundamental flavors, C P symmetry is spontaneously broken at θ =π , and domain wall solutions connecting the vacua can be constructed in chiral perturbation theory. In some cases the breaking of C P saturates a 't Hooft anomaly, and anomaly inflow requires nontrivial massless excitations on the domain walls. Analogously, C P can be spontaneously broken in supersymmetric QCD (SQCD) with light flavors and small soft breaking parameters. We study C P breaking and domain walls in softly broken SQCD with Nfcomputed at leading order in the soft breaking parameters, producing a phase diagram for the stable wall trajectory. We also comment on domain walls in the similar case of QCD with an adjoint and fundamental flavors, and on the impact of adding an axion in this theory.

  20. Floating convection barrier for evaporation source

    International Nuclear Information System (INIS)

    1975-01-01

    A floating matrix of titanium in an uranium evaporation source, melted by an electron beam, serves as a barrier for preventing cooler material from reaching the evaporation area. This construction allows a big volume of melted uranium to be present and new uranium to be furnished in regulated intervals without manual intervention

  1. Atomistic modeling of the structural components of the blood-brain barrier

    Science.gov (United States)

    Glukhova, O. E.; Grishina, O. A.; Slepchenkov, M. M.

    2015-03-01

    Blood-brain barrier, which is a barrage system between the brain and blood vessels, plays a key role in the "isolation" of the brain of unnecessary information, and reduce the "noise" in the interneuron communication. It is known that the barrier function of the BBB strictly depends on the initial state of the organism and changes significantly with age and, especially in developing the "vascular accidents". Disclosure mechanisms of regulation of the barrier function will develop new ways to deliver neurotrophic drugs to the brain in the newborn. The aim of this work is the construction of atomistic models of structural components of the blood-brain barrier to reveal the mechanisms of regulation of the barrier function.

  2. Neutron-transparent first wall for module testing

    International Nuclear Information System (INIS)

    Fuller, G.M.; Cramer, B.A.; Haines, J.R.; Kirchner, J.; Engholm, B.A.; Seki, M.

    1983-01-01

    Major design goals for FED-R are the achievement of: (1) a high level of neutron exposure of the test modules and (2) a capability for rapid changeout of test modules. A major factor in rapid changeout is perceived to be the location of the vacuum boundary. In FED-R this boundary was set at the first wall so that module changeout did not require the plasma chamber to be brought up to atmosphere. Efforts to realize these goals in the design resulted in a neutronically thin outboard wall for the vacuum vessel constructed of 316 stainless steel (SS) with helium as a coolant. A normalized 14-MeV neutron transmission of 0.82 is expected, with an inlet pressure of 2 MPa and a pumping power requirement of 8.7 MW. Other options considered in the study were aluminum as a wall material and water and sodium potassium (NaK) as coolants

  3. Bentonite engineered barrier building method for radioactive waste on sub-surface disposal test project

    International Nuclear Information System (INIS)

    Mori, Takuo; Takahashi, Shinichi; Takeuchi, Kunifumi; Namiki, Kazuto

    2008-01-01

    The engineering barriers such as clay and concrete materials are planned to use for covering radioactive waste in cavern-type disposal facility. The requirement to clay barrier is very low permeability, which could be satisfied by high density Bentonite, and such a compaction method will be needed. Two methods, compaction and air shot, were tested in engineering scale for constructing a high-density clay barrier. Two types of compaction equipments, 'Teasel plate' and 'Plate compacter', were developed and engineering scale experiments were performed for compacting Bentonite only and Bentonite-sand-aggregate mixture. As a result, the Teasel plate can reach higher density Bentonite in relatively short time in comparison to other equipments. While, regarding air shot method, an air-shot machine in a tunnel construction site was tested by different water adding methods (wet, dry, and half wet). It is concluded that the dry and half wet constructing methods will achieve reasonable workability. As a result, the best construction option can be chosen according to the locations of radioactive waste facility. (author)

  4. Demystifying the Barriers to Transport Infrastructure Project Development in Fast Developing Regions: The Case of China

    Directory of Open Access Journals (Sweden)

    Tianyi Nie

    2017-10-01

    Full Text Available Transport infrastructure (TI has become one of the primary drivers for sustainable economic growth and social progress. However, a wider take-up is currently inhibited in fast developing regions (FDRs by many barriers, which have not been explored explicitly in previous studies. In this study, a three-dimensional framework (i.e., macro environment, local environment, and the construction process is proposed to structure the barriers in a reasonable way. Professionals’ opinions on the importance of the barriers are collected through questionnaire survey. The survey results were analyzed by the ranking analysis technique. It is found that the top five barriers are “difficulty in survey and design during the construction process”, “weak support from economy”, “insufficient funding”, “harsh regional climate”, and “cost overrun”. Further analysis, based on a factor analysis, indicates that these critical barriers could be grouped into three clusters: “administration on transport infrastructure”, “construction technology and cost management”, and “geographical and economic conditions”. The research findings demonstrate the usefulness of the proposed framework, and the implication is that a barriers-based checklist favors stakeholders to improve the efficiency and sustainability of TI development in FDRs. Although the study is situated in China, it sheds light on the subject in other developing countries.

  5. Seismic Vulnerability and Performance Level of confined brick walls

    International Nuclear Information System (INIS)

    Ghalehnovi, M.; Rahdar, H. A.

    2008-01-01

    There has been an increase on the interest of Engineers and designers to use designing methods based on displacement and behavior (designing based on performance) Regarding to the importance of resisting structure design against dynamic loads such as earthquake, and inability to design according to prediction of nonlinear behavior element caused by nonlinear properties of constructional material.Economically speaking, easy carrying out and accessibility of masonry material have caused an enormous increase in masonry structures in villages, towns and cities. On the other hand, there is a necessity to study behavior and Seismic Vulnerability in these kinds of structures since Iran is located on the earthquake belt of Alpide.Different reasons such as environmental, economic, social, cultural and accessible constructional material have caused different kinds of constructional structures.In this study, some tied walls have been modeled with software and with relevant accelerator suitable with geology conditions under dynamic analysis to research on the Seismic Vulnerability and performance level of confined brick walls. Results from this analysis seem to be satisfactory after comparison of them with the values in Code ATC40, FEMA and standard 2800 of Iran

  6. Seismic Vulnerability and Performance Level of confined brick walls

    Science.gov (United States)

    Ghalehnovi, M.; Rahdar, H. A.

    2008-07-01

    There has been an increase on the interest of Engineers and designers to use designing methods based on displacement and behavior (designing based on performance) Regarding to the importance of resisting structure design against dynamic loads such as earthquake, and inability to design according to prediction of nonlinear behavior element caused by nonlinear properties of constructional material. Economically speaking, easy carrying out and accessibility of masonry material have caused an enormous increase in masonry structures in villages, towns and cities. On the other hand, there is a necessity to study behavior and Seismic Vulnerability in these kinds of structures since Iran is located on the earthquake belt of Alpide. Different reasons such as environmental, economic, social, cultural and accessible constructional material have caused different kinds of constructional structures. In this study, some tied walls have been modeled with software and with relevant accelerator suitable with geology conditions under dynamic analysis to research on the Seismic Vulnerability and performance level of confined brick walls. Results from this analysis seem to be satisfactory after comparison of them with the values in Code ATC40, FEMA and standard 2800 of Iran.

  7. Nuclear reactor vessel fuel thermal insulating barrier

    Science.gov (United States)

    Keegan, C. Patrick; Scobel, James H.; Wright, Richard F.

    2013-03-19

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

  8. Hanford prototype-barrier status report: FY 1997

    International Nuclear Information System (INIS)

    Ward, A.L.; Gee, G.W.; Link, S.O.

    1997-12-01

    An above-grade surface barrier consisting of a vegetated soil-cover, surrounded by gravel and rock side slopes, is being tested for the US Department of Energy (DOE). It is part of a treatability study at the 200-BP-1 Operable Unit in the 200 East Area of the Hanford Site, near Richland, Washington. The surface barrier, constructed in 1994, covers 2.5 ha (6.9 acre) of land surface and is situated over an inactive liquid-waste disposal crib. A set of under drains, built into the barrier using curbed asphalt, allows precise measurement of drainage from the soil cover and the side slopes. The treatability test includes measurements of water balance, wind and water erosion, subsidence, plant growth, and plant and animal intrusion. The test compares the performance of the barrier under ambient and simulated climate change (elevated precipitation) conditions. This report documents findings from the third year of testing

  9. Construction solutions for the exterior walls in the process of increasing the width of residential buildings of brownfield construction in seismic hazardousand dry hot conditions of Central Asia

    Directory of Open Access Journals (Sweden)

    Usmonov Shukhrat Zaurovich

    2014-02-01

    Full Text Available The main object of this study is the reconstruction, renovation and modernization of the housing built in the period 1975—1985. These buildings have low energy efficiency due to the poor thermal insulation properties of the walls. These apartments do not meet the necessary requirements for year round warmth and comfort.Reconstruction is more preferable, than new-build, because of the cost saving for the land acquisition. Reconstruction is generally 1.5 times cheaper than new-build with 25—40 % reduced cost on building materials and engineering infrastructure.Increasing the width of the apartment blocks from 12 to 15 m can save 9—10 % on the consumption of thermal energy for heating and reduce the m2 construction cost by 5.5—7.0 %. In—5-9 storey high-rise buildings the savings are 3—5 %.Therefore, the width of the apartment block should preferably be between 9—12 m but could be extended to 18 m. The depth of the apartments themselves will be 5.4 — 6.0 —7.2 or 9.0 m. During the reconstruction of 5-storey residential buildings (Building Type105 in a seismic zone, an increase in the width of the block and the lateral stiffness of the building is achieved by building a new reinforced concrete (RC frame on both sides of the building with a depth of between 2 and 6 m. This technique is especially effective in increasing the seismic resistance of the building. Self-supporting walls of cellular concrete blocks (density 600 kg/m3 and a thickness of 300 mm are constructed on the outside of the frame, taking care to avoid cold bridges.Model studies have shown that in the conditions of hot-arid climate the thickness of the air gap in a ventilated facade does not significantly change the cooling-energy consumption of the building, and heating consumption is significantly increased. The building's energy consumption is most influenced by the volume of the air in the air gap. By increasing the ventilation rate in the air gap, the energy

  10. Wall-crossing, Rogers dilogarithm, and the QK/HK correspondence

    CERN Document Server

    Alexandrov, Sergei; Pioline, Boris

    2011-01-01

    When formulated in twistor space, the D-instanton corrected hypermultiplet moduli space in N=2 string vacua and the Coulomb branch of rigid N=2 gauge theories on $R^3 \\times S^1$ are strikingly similar and, to a large extent, dictated by consistency with wall-crossing. We elucidate this similarity by showing that these two spaces are related under a general duality between, on one hand, quaternion-Kahler manifolds with a quaternionic isometry and, on the other hand, hyperkahler manifolds with a rotational isometry, further equipped with a hyperholomorphic circle bundle with a connection. We show that the transition functions of the hyperholomorphic circle bundle relevant for the hypermultiplet moduli space are given by the Rogers dilogarithm function, and that consistency across walls of marginal stability is ensured by the motivic wall-crossing formula of Kontsevich and Soibelman. We illustrate the construction on some simple examples of wall-crossing related to cluster algebras for rank 2 Dynkin quivers. In...

  11. Experimental study on lateral strength of wall-slab joint subjected to lateral cyclic load

    Science.gov (United States)

    Masrom, Mohd Asha'ari; Mohamad, Mohd Elfie; Hamid, Nor Hayati Abdul; Yusuff, Amer

    2017-10-01

    Tunnel form building has been utilised in building construction since 1960 in Malaysia. This method of construction has been applied extensively in the construction of high rise residential house (multistory building) such as condominium and apartment. Most of the tunnel form buildings have been designed according to British standard (BS) whereby there is no provision for seismic loading. The high-rise tunnel form buildings are vulnerable to seismic loading. The connections between slab and shear walls in the tunnel-form building constitute an essential link in the lateral load resisting mechanism. Malaysia is undergoing a shifting process from BS code to Eurocode (EC) for building construction since the country has realised the safety threats of earthquake. Hence, this study is intended to compare the performance of the interior wall slab joint for a tunnel form structure designed based on Euro and British codes. The experiment included a full scale test of the wall slab joint sub-assemblages under reversible lateral cyclic loading. Two sub-assemblage specimens of the wall slab joint were designed and constructed based on both codes. Each specimen was tested using lateral displacement control (drift control). The specimen designed by using Eurocode was found could survive up to 3.0% drift while BS specimen could last to 1.5% drift. The analysis results indicated that the BS specimen was governed by brittle failure modes with Ductility Class Low (DCL) while the EC specimen behaved in a ductile manner with Ductility Class Medium (DCM). The low ductility recorded in BS specimen was resulted from insufficient reinforcement provided in the BS code specimen. Consequently, the BS specimen could not absorb energy efficiently (low energy dissipation) and further sustain under inelastic deformation.

  12. Life cycle cost of different Walling material used for affordable housing in tropics

    Directory of Open Access Journals (Sweden)

    Chameera Udawattha

    2017-12-01

    The results show that mud concrete block is the most suitable walling material. The brick has the highest account for the embedded energy. The hollow cement block is the worse building materials in tropics and its carbon footprint is comparatively higher. Even though the brick has higher embedded energy and construction cost, in a long run brick is less expensive than hollow cement block and Cabook walling material. Concluding, mud concrete block is comparatively most sustainable walling material for building affordable housing in tropics.

  13. Frozen Soil Barrier. Subsurface Contaminants Focus Area. OST Reference No. 51

    International Nuclear Information System (INIS)

    1999-01-01

    Problem: Hazardous and radioactive materials have historically been disposed of at the surface during operations at Department of Energy facilities. These contaminants have entered the subsurface, contaminating soils and groundwater resources. Remediation of these groundwater plumes using the baseline technology of pump and treat is expensive and takes a long time to complete. Containment of these groundwater plumes can be alternative or an addition to the remediation activities. Standard containment technologies include slurry walls, sheet piling, and grouting. These are permanent structures that once installed are difficult to remove. How It Works: Frozen Soil Barrier technology provides a containment alternative, with the key difference being that the barrier can be easily removed after a period of time, such as after the remediation or removal of the source is completed. Frozen Soil Barrier technology can be used to isolate and control the migration of underground radioactive or other hazardous contaminants subject to transport by groundwater flow. Frozen Soil Barrier technology consists of a series of subsurface heat transfer devices, known as thermoprobes, which are installed around a contaminant source and function to freeze the soil pore water. The barrier can easily be maintained in place until remediation or removal of the contaminants is complete, at which time the barrier is allowed to thaw.

  14. Field-driven sense elements for chirality-dependent domain wall detection and storage

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, S. R. [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Maryland Nanocenter, University of Maryland, College Park, Maryland 20742 (United States); Unguris, J. [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    2013-12-14

    A method for locally sensing and storing data of transverse domain wall chirality in planar nanowire logic and memory systems is presented. Patterned elements, in close proximity to the nanowires, respond to the asymmetry in the stray field from the domain wall to produce a chirality-dependent response. When a bias field is applied, a stray field-assisted reversal of the element magnetization results in a reversed remanent state, measurable by scanning electron microscopy with polarization analysis (SEMPA). The elements are designed as triangles with tips pointing toward the nanowire, allowing the shape anisotropy to be dominated by the base but having a portion with lower volume and lower energy barrier closest to the domain wall. Micromagnetic modeling assists in the design of the nanowire-triangle systems and experiments using SEMPA confirm the importance of aspect ratio and spacing given a constant bias field magnitude.

  15. A tunable acoustic barrier based on periodic arrays of subwavelength slits

    Directory of Open Access Journals (Sweden)

    Constanza Rubio

    2015-05-01

    Full Text Available The most usual method to reduce undesirable enviromental noise levels during its transmission is the use of acoustic barriers. A novel type of acoustic barrier based on sound transmission through subwavelength slits is presented. This system consists of two rows of periodic repetition of vertical rigid pickets separated by a slit of subwavelength width and with a misalignment between them. Here, both the experimental and the numerical analyses are presented. The acoustic barrier proposed can be easily built and is frequency tunable. The results demonstrated that the proposed barrier can be tuned to mitigate a band noise without excesive barrier thickness. The use of this system as an environmental acoustic barrier has certain advantages with regard to the ones currently used both from the constructive and the acoustical point of view.

  16. A tunable acoustic barrier based on periodic arrays of subwavelength slits

    Science.gov (United States)

    Rubio, Constanza; Uris, Antonio; Candelas, Pilar; Belmar, Francisco; Gomez-Lozano, Vicente

    2015-05-01

    The most usual method to reduce undesirable enviromental noise levels during its transmission is the use of acoustic barriers. A novel type of acoustic barrier based on sound transmission through subwavelength slits is presented. This system consists of two rows of periodic repetition of vertical rigid pickets separated by a slit of subwavelength width and with a misalignment between them. Here, both the experimental and the numerical analyses are presented. The acoustic barrier proposed can be easily built and is frequency tunable. The results demonstrated that the proposed barrier can be tuned to mitigate a band noise without excesive barrier thickness. The use of this system as an environmental acoustic barrier has certain advantages with regard to the ones currently used both from the constructive and the acoustical point of view.

  17. The effect of desiccation on UMTRA Project radon barrier materials

    International Nuclear Information System (INIS)

    1990-11-01

    The proposed US Environmental Protection Agency (EPA) groundwater standards (40 CFR 192) require that Uranium Mill Tailings Remedial Action (UMTRA) Project remedial action designs meet low numerical limits for contaminants contained in water or vapors exiting the disposal cell embankments. To meet the standards, a cover of compacted, fine-grained soil is placed over UMTRA Project embankments. One of the functions of this cover is to limit infiltration into the disposal cell . The hydraulic conductivity of this infiltration barrier must be low in order to reduce the resultant seepage from the base of the cell to the extent necessary to comply with the proposed EPA groundwater standards. Another function of this cover is to limit the emission of radon gas. The air permeability of the cover must be low in order to reduce radon emissions to comply with EPA standards. Fine-grained soils exposed to evaporation will dry. Continued exposure will cause shrinking that, if allowed to continue, will eventually result in the development of cracks. The results of the cracking could be an increase in the hydraulic conductivity and an increase in the air permeability. This could then allow additional infiltration and increased radon emissions. Cracking of the radon barrier has been noted at one UMTRA Project location. The potential for cracking of the radon barrier during construction has been addressed by requiring moistening of previously compacted surfaces prior to placing additional lifts. The efficacy of these treatments has not been verified. The potential for cracking after construction of the cover is completed has also not been examined. The purpose of this study is to evaluate the potential for cracking of the radon barrier both during construction and after completion of the cover. The effect of shrinkage cracking on the performance of the radon barrier will also be examined

  18. Effects of the build-in-moisture on indoor climate and wood moisture of timber mixed construction; Auswirkungen der Baurestfeuchte auf Innenklima und Holzfeuchte bei Holz-Mischbauweisen

    Energy Technology Data Exchange (ETDEWEB)

    Teibinger, Martin [Holzforschung Austria, Franz Grill Strasse 7, A-1030 Wien (Austria); Bednar, Thomas [Institut fuer Hochbau und Technologie, Zentrum fuer Bauphysik und Bauakustik, Karlsplatz 13/206, A-1030 Wien (Austria)

    2005-10-01

    Within the scope of the competence center ''wood technology'' the Holzforschung Austria deals with the combination of prefabricated timber elements in the building shell with concrete construction parts for high rise buildings. In addition to the design of construction details a one-zone model has been created - in close collaboration with the Technical University of Vienna - to analyze the effects of residual humidity on the internal climate and on the moisture content of the timber elements. The simulated drying properties of the concrete elements are consistent with the results of the analysis of the Verein der Oesterreichischen Zementfabrikanten in matters of drying time and change of moisture content. In addition to the variation of the beginning and progress of construction work and the behavior of air conditioning three different exterior wall constructions - one timber frame construction with OSB and one with PE as vapour barrier and a construction with solid timber boards without vapour barrier have been analysed. (Abstract Copyright [2005], Wiley Periodicals, Inc.) [German] Im Rahmen des Kompetenzzentrums ''Holztechnologie'' beschaeftigt sich die Holzforschung Austria mit den Kombinationsmoeglichkeiten von hochwaermegedaemmten Holzelementen in der Gebaeudehuelle mit einer mineralischen Tragstruktur fuer den urbanen Wohnungsbau. Neben der Entwicklung von Anschlussdetails wurde u. a. in Zusammenarbeit mit der Technischen Universitaet Wien ein Modell zur Untersuchung des Einflusses der Baurestfeuchte auf die Holzelemente entwickelt. Das simulierte Trocknungsverhalten der mineralischen Bauteile stimmt sowohl hinsichtlich Trocknungszeiten als auch hinsichtlich Feuchteabgabe mit den Untersuchungen des Vereins der Oesterreichischen Zementfabrikanten ueberein. Neben der Variation des Baubeginns, des Baufortschrittes und des Lueftungsverhaltens wurden als Aussenwandelemente Holzrahmenkonstruktionen mit einer OSB

  19. Flair Homes Project report no. 5. Airtightness performance of twenty detached houses over a two-year period

    Energy Technology Data Exchange (ETDEWEB)

    Proskiw, G.; Beckman, J.

    1989-01-01

    Airtightness tests were performed on 20 new houses over a 2-year period in Winnipeg. The houses were constructed with a variety of air/vapor barrier systems and 3 different types of main walls. Polyethylene was used as the air/vapor barrier in 6 of the houses while the remaining 14 used the airtight drywall approach (ADA). The houses had similar floor plans and were constructed by the same builder. Both the polyethylene and ADA systems were found to be capable of meeting the airtightness requirements of the R-2000 standard with the tightest structures being double wall houses. No significant or permanent change in airtightness was observed for any of the houses over the monitoring period. Application of stucco as an exterior finish was found to improve airtightness of the ADA houses, but not of the double wall houses with polyethylene vapor barriers. Consistent sources of air leakage in the ADA houses were found to be the electrical outlets on exterior walls. Window leakage was also noted in many houses and the frequency of this leakage increased over the monitoring period. A significant leakage source was found to be an integrated mechanical system, which ducted in large volumes of outdoor air. It was also concluded there is a need to re-examine the design pressure requirements for residential air barrier systems. Specifically, this should investigate how transient wind-induced pressure loads are resisted by air barrier systems and whether some portion of the load is taken by other envelope components. An air leakage detection system was proposed consisting of a simple non-instrumented blower, which would be suitable for use by builders to aid in the construction of low leakage houses. 17 refs., 10 figs., 8 tabs.

  20. Minimum wall pressure coefficient of orifice plate energy dissipater

    Directory of Open Access Journals (Sweden)

    Wan-zheng Ai

    2015-01-01

    Full Text Available Orifice plate energy dissipaters have been successfully used in large-scale hydropower projects due to their simple structure, convenient construction procedure, and high energy dissipation ratio. The minimum wall pressure coefficient of an orifice plate can indirectly reflect its cavitation characteristics: the lower the minimum wall pressure coefficient is, the better the ability of the orifice plate to resist cavitation damage is. Thus, it is important to study the minimum wall pressure coefficient of the orifice plate. In this study, this coefficient and related parameters, such as the contraction ratio, defined as the ratio of the orifice plate diameter to the flood-discharging tunnel diameter; the relative thickness, defined as the ratio of the orifice plate thickness to the tunnel diameter; and the Reynolds number of the flow through the orifice plate, were theoretically analyzed, and their relationships were obtained through physical model experiments. It can be concluded that the minimum wall pressure coefficient is mainly dominated by the contraction ratio and relative thickness. The lower the contraction ratio and relative thickness are, the larger the minimum wall pressure coefficient is. The effects of the Reynolds number on the minimum wall pressure coefficient can be neglected when it is larger than 105. An empirical expression was presented to calculate the minimum wall pressure coefficient in this study.

  1. Exploring the Role of Cell Wall-Related Genes and Polysaccharides during Plant Development.

    Science.gov (United States)

    Tucker, Matthew R; Lou, Haoyu; Aubert, Matthew K; Wilkinson, Laura G; Little, Alan; Houston, Kelly; Pinto, Sara C; Shirley, Neil J

    2018-05-31

    The majority of organs in plants are not established until after germination, when pluripotent stem cells in the growing apices give rise to daughter cells that proliferate and subsequently differentiate into new tissues and organ primordia. This remarkable capacity is not only restricted to the meristem, since maturing cells in many organs can also rapidly alter their identity depending on the cues they receive. One general feature of plant cell differentiation is a change in cell wall composition at the cell surface. Historically, this has been viewed as a downstream response to primary cues controlling differentiation, but a closer inspection of the wall suggests that it may play a much more active role. Specific polymers within the wall can act as substrates for modifications that impact receptor binding, signal mobility, and cell flexibility. Therefore, far from being a static barrier, the cell wall and its constituent polysaccharides can dictate signal transmission and perception, and directly contribute to a cell's capacity to differentiate. In this review, we re-visit the role of plant cell wall-related genes and polysaccharides during various stages of development, with a particular focus on how changes in cell wall machinery accompany the exit of cells from the stem cell niche.

  2. Tourism Development: Issues for Historic Walled Towns = Razvoj turizma v mestih z obzidjem

    Directory of Open Access Journals (Sweden)

    David Bruce

    2009-06-01

    Full Text Available This paper discusses issues in tourism development and visitor management in historic walled towns. Historic towns and walled towns in particular, attract tourists that enjoy the preserved medieval ambience, architecture and picturesque streets. Tourism has an impact on economic and social life as well as on the urban and natural environment. Walled towns and cities with their obvious barriers exemplify and crystallise issues, challenges, and opportunities critical to the development of tourism. A research designed to identify issues related to tourism development and visitor management in walled towns included an extensive questionnaire and two workshops. Eight European historic/ walled towns were included in the research: Chester (United Kingdom, Piran (Slovenia, ’s-Hertogenbosch (Netherlands, Valetta (Malta, Arabarri (Spain, Lucca (Italy, Lörrach (Germany, and Verona (Italy. The questionnaire was used to identify the tourism profile of participating towns as well as the issues and concerns related to tourism development. Participating towns discussed their concerns and exchanged their views and good practices at two workshops. Identified issues include providing adequate tourist information, involvement of residents in tourism development, development of products to decrease seasonality, and concentration of tourism demand. The paper presents good practices and suggests solutions in solving tourism related issues in historic walled towns.

  3. Evaluation of Steel Shear Walls Behavior with Sinusoidal and Trapezoidal Corrugated Plates

    Directory of Open Access Journals (Sweden)

    Emad Hosseinpour

    2015-01-01

    Full Text Available Reinforcement of structures aims to control the input energy of unnatural and natural forces. In the past four decades, steel shear walls are utilized in huge constructions in some seismic countries such as Japan, United States, and Canada to lessen the risk of destructive forces. The steel shear walls are divided into two types: unstiffened and stiffened. In the former, a series of plates (sinusoidal and trapezoidal corrugated with light thickness are used that have the postbuckling field property under overall buckling. In the latter, steel profile belt series are employed as stiffeners with different arrangement: horizontal, vertical, or diagonal in one side or both sides of wall. In the unstiffened walls, increasing the thickness causes an increase in the wall capacity under large forces in tall structures. In the stiffened walls, joining the stiffeners to the wall is costly and time consuming. The ANSYS software was used to analyze the different models of unstiffened one-story steel walls with sinusoidal and trapezoidal corrugated plates under lateral load. The obtained results demonstrated that, in the walls with the same dimensions, the trapezoidal corrugated plates showed higher ductility and ultimate bearing compared to the sinusoidal corrugated plates.

  4. Experimental study of fire barriers preventing vertical fire spread in ETISs

    Directory of Open Access Journals (Sweden)

    Xin Huang

    2013-11-01

    Full Text Available In recent years, the external thermal insulation system (ETIS has been applied increasingly in a large amount of buildings for energy conservation purpose. However, the increase use of combustible insulation materials in the ETIS has raised serious fire safety problems. Fires involving this type of ETIS have caused severe damage and loss. In order to improve its fire safety, fire barriers were suggested to be installed. This paper introduces fire experiments that have been done to study the effects of fire barriers on preventing vertical fire spread along the ETIS. The experiments were performed according to BS 8414-1:2002 “Fire performance of external cladding systems – Part 1: Test method for non-loadbearing external cladding systems applied to the face of the building”. The test facility consists of a 9 m high wall. The fire sources were wood cribs with a fire size of 3 ± 0.5 MW. The insulation materials were expanded polystyrene foam (EPS. The fire barrier was a horizontal strip of rockwool with a width of 300 mm. Thermocouples were used to measure temperatures outside and inside the ETIS. A series of experiments with different fire scenarios were done: no fire barrier, two fire barriers and three fire barriers at different heights. Test results were compared. The results show that the ETIS using EPS without fire barriers almost burned out, while the ETIS with fire barriers performed well in preventing fire spread. The temperatures above the fire barrier were much lower than those below the fire barrier, and most of the insulation materials above the top fire barrier stayed in place.

  5. Dam construction in salt rock

    International Nuclear Information System (INIS)

    Stockmann, N.; Beinlich, A.; Flach, D.; Jockwer, N.; Klarr, K.; Krogmann, P.; Miehe, R.; Schmidt, M.W.; Schwaegermann, H.F.; Walter, F.; Yaramanci, U.

    1991-11-01

    Barriers are a major component of the satefy concept for the Gorleben repository. The construction and performance of dams are currently tested within the framework of a project carried out in the Asse salt mine. A measuring programme has been established to give evidence of the sealing capacities of a barrier consisting of an abatement, long-term sealing material, and a hydraulic sealing system. Tests are to be made to verify the barrier's performance for shorter of long time periods (up to about 500 years). The tests are assisted by computed models established for the project. The long-term safety aspects to be studied include such conditions as permeability changes due to mechanical impacts, circulation conditions at the roadside, and the serviceable life and efficiency of the sealing components. (DG) [de

  6. Using "The Wall Street Journal" To Stimulate Critical Thinking.

    Science.gov (United States)

    Roever, Carol

    1998-01-01

    Describes an assignment in a business-communication class in which student teams construct portfolios with articles from "The Wall Street Journal," explaining and clearly expressing how these articles relate to class concepts. Argues that the assignment encourages critical-thinking skills, focuses on writing skills, and develops an…

  7. Nuclear power plant containment construction

    International Nuclear Information System (INIS)

    Schabert, H.P.; Danisch, R.; Strickroth, E.

    1975-01-01

    The Nuclear Power Plant Containment Construction includes the spherical steel safety enclosure for the reactor and the equipment associated with the reactor and requiring this type of enclosure. This steel enclosure is externally structurally protected against accident by a concrete construction providing a foundation for the steel enclosure and having a cylindrical wall and a hemispherical dome, these parts being dimensioned to form an annular space surrounding the spherical steel enclosure, the latter and the concrete construction heretofore being concentrically arranged with respect to each other. In the disclosed construction the two parts are arranged with their vertical axis horizontally offset from each other so that opposite to the offsetting direction of the concrete construction a relatively large space is formed in the now asymmetrical annular space in which reactor auxiliary equipment not requiring enclosure by the steel containment vessel or safety enclosure, may be located outside of the steel containment vessel and inside of the concrete construction where it is structurally protected by the latter

  8. On domain wall boundary conditions for the XXZ spin Hamiltonian

    DEFF Research Database (Denmark)

    Orlando, Domenico; Reffert, Susanne; Reshetikhin, Nicolai

    In this note, we derive the spectrum of the infinite quantum XXZ spin chain with domain wall boundary conditions. The eigenstates are constructed as limits of Bethe states for the finite XXZ spin chain with quantum sl(2) invariant boundary conditions....

  9. Domain wall solitons and Hopf algebraic translational symmetries in noncommutative field theories

    International Nuclear Information System (INIS)

    Sasai, Yuya; Sasakura, Naoki

    2008-01-01

    Domain wall solitons are the simplest topological objects in field theories. The conventional translational symmetry in a field theory is the generator of a one-parameter family of domain wall solutions, and induces a massless moduli field which propagates along a domain wall. We study similar issues in braided noncommutative field theories possessing Hopf algebraic translational symmetries. As a concrete example, we discuss a domain wall soliton in the scalar φ 4 braided noncommutative field theory in Lie-algebraic noncommutative space-time, [x i ,x j ]=2iκε ijk x k (i,j,k=1,2,3), which has a Hopf algebraic translational symmetry. We first discuss the existence of a domain wall soliton in view of Derrick's theorem, and construct explicitly a one-parameter family of solutions in perturbation of the noncommutativity parameter κ. We then find the massless moduli field which propagates on the domain wall soliton. We further extend our analysis to the general Hopf algebraic translational symmetry

  10. Copper alloy conducting first wall for the FED-A tokamak

    International Nuclear Information System (INIS)

    Wiffen, F.W.

    1984-01-01

    The first wall of the tokamak FED-A device was designed to satisfy two conflicting requirements. They are a low electrical resistance to give a long eddy-current decay time and a high neutron transparency to give a favorable tritium breeding ratio. The tradeoff between these conflicting requirements resulted in a copper alloy first wall that satisfied the specific goals for FED-A, i.e., a minimum eddy-current decay time of 0.5 sec and a tritium breeding ratio of at least 1.2. Aluminum alloys come close to meeting the requirements and would also probably work. Stainless steel will not work in this application because shells thin enough to satisfy temperature and stress limits are not thick enough to give a long eddy-current decay time and to avoid disruption induced melting. The baseline first wall design is a rib-stiffened, double-wall construction. The total wall thickness is 1.5 cm, including a water coolant thickness of 0.5 cm. The first wall is divided into twelve 30-degree sectors. Flange rings at the ends of each sector are bolted together to form the torus. Structural support is provided at the top center of each sector

  11. [Construction of research system for processing mechanism of traditional Chinese medicine based on chemical composition transformation combined with intestinal absorption barrier].

    Science.gov (United States)

    Sun, E; Xu, Feng-Juan; Zhang, Zhen-Hai; Wei, Ying-Jie; Tan, Xiao-Bin; Cheng, Xu-Dong; Jia, Xiao-Bin

    2014-02-01

    Based on practice of Epimedium processing mechanism for many years and integrated multidisciplinary theory and technology, this paper initially constructs the research system for processing mechanism of traditional Chinese medicine based on chemical composition transformation combined with intestinal absorption barrier, which to form an innovative research mode of the " chemical composition changes-biological transformation-metabolism in vitro and in vivo-intestinal absorption-pharmacokinetic combined pharmacodynamic-pharmacodynamic mechanism". Combined with specific examples of Epimedium and other Chinese herbal medicine processing mechanism, this paper also discusses the academic thoughts, research methods and key technologies of this research system, which will be conducive to systematically reveal the modem scientific connotation of traditional Chinese medicine processing, and enrich the theory of Chinese herbal medicine processing.

  12. Ultra-High-Performance Concrete And Advanced Manufacturing Methods For Modular Construction

    Energy Technology Data Exchange (ETDEWEB)

    Sawab, Jamshaid [Univ. of Houston, Houston, TX (United States); Lim, Ing [Univ. of Houston, Houston, TX (United States); Mo, Yi-Lung [Univ. of Houston, Houston, TX (United States); Li, Mo [Univ. of Houston, Houston, TX (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Guimaraes, Maria [Electric Power Research Inst. (EPRI), Knoxville, TN (United States)

    2016-04-13

    containment structures to resist lateral forces induced by severe earthquakes and heavy winds. SC modules have good potential for SMR because of their cost-effectiveness and reduced construction time. However, the minimum shear reinforcement (i.e. cross tie) ratio needs to be determined for the steel plate-UHPC (S-UHPC) beams to exhibit a ductile failure mode. In this project, S-UHPC beams were designed and constructed. The beams were tested to evaluate structural capacity and identify the minimum cross ties ratios. In addition, as the bond between UHPC and steel plate is essential for ensuring structural integrity under shear and flexure, it was measured and examined in this project through digital image correlation system and smart piezoelectric aggregate sensors. Large-scale testing and finite element simulation were also performed on S-UHPC wall panels. New bond slip-based constitutive models of steel plate were developed for S-UHPC, which were used in finite element analysis program to predict S-UHPC behavior under shear. The results were well validated through experimental data. The long-term durability of UHPC were established in this project. UHPC specimens were tested under free shrinkage, restrained shrinkage, elevated temperature, water permeation, chloride diffusion, corrosion, and alkali silica reaction. UHPC has demonstrated significantly improved durability compared with control concrete specimens. This research led to a new generation of steel plate-UHPC modules for SMR that can provide large benefits to the electric power industry. Taking advantage of the high strength and durability of UHPC, their modularity and ease of assembly can address the high cost barriers of typical nuclear power plants.

  13. Extended Plate and Beam Wall System: Concept Investigation and Initial Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Kochkin, V. [Partnership for Home Innovation, Upper Marlboro, MD (United States)

    2015-08-01

    A new and innovative High-R wall design, referred to as the Extended Plate & Beam (EP&B), is under development. The EP&B system uniquely integrates foam sheathing insulation with wall framing such that wood structural panels are installed exterior of the foam sheathing, enabling the use of standard practices for installation of drainage plane, windows and doors, claddings, cavity insulation, and the standard exterior foam sheathing installation approach prone to damage of the foam during transportation of prefabricated wall panels. As part of the ongoing work, the EP&B wall system concept has undergone structural verification testing and has been positively vetted by a group of industry stakeholders. Having passed these initial milestone markers, the advanced wall system design has been analyzed to assess cost implications relative to other advanced wall systems, undergone design assessment to develop construction details, and has been evaluated to develop representative prescriptive requirements for the building code. This report summarizes the assessment steps conducted to-date and provides details of the concept development.

  14. Effects of a tetracycline blended polylactic and polyglycolic acid membrane on the healing of one-wall intrabony defects in beagle dogs

    International Nuclear Information System (INIS)

    Kim, Il-Young; Jung, Ui-Won; Kim, Chang-Sung; Lee, Yong-Keun; Cho, Kyoo-Sung; Chai, Jung-Kiu; Kim, Chong-Kwan; Choi, Seong-Ho

    2007-01-01

    The purpose of this study was to evaluate the regenerative effects of a tetracycline blended polylactic and polyglycolic acid (TC-PLGA) and non-blended polylactic and polyglycolic acid (PLGA) barrier membrane on one-wall intrabony defects in beagle dogs. It can be concluded that when used for guided tissue regeneration TC-PLGA membranes show a beneficial effect on one-wall intrabony defects in beagle dogs

  15. Significance of Shear Wall in Multi-Storey Structure With Seismic Analysis

    Science.gov (United States)

    Bongilwar, Rajat; Harne, V. R.; Chopade, Aditya

    2018-03-01

    In past decades, shear walls are one of the most appropriate and important structural component in multi-storied building. Therefore, it would be very interesting to study the structural response and their systems in multi-storied structure. Shear walls contribute the stiffness and strength during earthquakes which are often neglected during design of structure and construction. This study shows the effect of shear walls which significantly affect the vulnerability of structures. In order to test this hypothesis, G+8 storey building was considered with and without shear walls and analyzed for various parameters like base shear, storey drift ratio, lateral displacement, bending moment and shear force. Significance of shear wall has been studied with the help of two models. First model is without shear wall i.e. bare frame and other another model is with shear wall considering opening also in it. For modeling and analysis of both the models, FEM based software ETABS 2016 were used. The analysis of all models was done using Equivalent static method. The comparison of results has been done based on same parameters like base shear, storey drift ratio, lateral displacement, bending moment and shear force.

  16. Tracking Walls, Take-It-Or-Leave-It Choices, the GDPR, and the ePrivacy Regulation

    NARCIS (Netherlands)

    Zuiderveen Borgesius, F.J.; Kruikemeier, S.; Boerman, S.C.; Helberger, N.

    2017-01-01

    On the internet, we encounter take-it-or-leave-it choices regarding our privacy on a daily basis. In Europe, online tracking for targeted advertising generally requires the internet users’ consent to be lawful. Some websites use a tracking wall, a barrier that visitors can only pass if they consent

  17. Documentation for Calculations of Standard Fire Resistance of Slabs and Walls of Concrete with Expanded Clay Aggregate

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    A number of full-scale tests are made in order to document calculation methods for fire-exposed slabs and walls derived during a previous project on fire exposed light-weight aggregate concrete constructions. The calculation methods are derived, and thus have a logical connection with the calcula......A number of full-scale tests are made in order to document calculation methods for fire-exposed slabs and walls derived during a previous project on fire exposed light-weight aggregate concrete constructions. The calculation methods are derived, and thus have a logical connection...... with the calculation methods used for other load cases. In addition the methods are shown to be valid for heavy concrete constructions by cooperation with tests for beams and columns, and a few slabs and walls. The two test series phase 1 and 2 of this report can therefore be seen as a necessary supplement to show...... that the methods are applicable for slabs and walls of light weight aggregate concrete. It is shown that the temperatures for standard fire exposed cross sections can be calculated, that the ultimate moment capacity can be calculated for slabs, and that the anchorage capacity and the shear tension capacity can...

  18. 76 FR 34145 - Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL

    Science.gov (United States)

    2011-06-13

    ...-AA00 Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL AGENCY.... Construction on Barrier IIB has been completed. Operational and safety testing was conducted in February 2011... dispersal barrier IIA and IIB. This safety zone will be enforced daily from 7 a.m. to 11 a.m. and from 1 p.m...

  19. 77 FR 36231 - Americans With Disabilities Act (ADA) and Architectural Barriers Act (ABA) Accessibility...

    Science.gov (United States)

    2012-06-18

    ...-0004] RIN 3014-AA39 Americans With Disabilities Act (ADA) and Architectural Barriers Act (ABA... (ADA) and Architectural Barriers Act (ABA) Accessibility Guidelines to specifically address emergency... ensure that newly constructed and altered emergency transportable housing units covered by the ADA or ABA...

  20. Thermal Insulating Concrete Wall Panel Design for Sustainable Built Environment

    Science.gov (United States)

    Zhou, Ao; Wong, Kwun-Wah

    2014-01-01

    Air-conditioning system plays a significant role in providing users a thermally comfortable indoor environment, which is a necessity in modern buildings. In order to save the vast energy consumed by air-conditioning system, the building envelopes in envelope-load dominated buildings should be well designed such that the unwanted heat gain and loss with environment can be minimized. In this paper, a new design of concrete wall panel that enhances thermal insulation of buildings by adding a gypsum layer inside concrete is presented. Experiments have been conducted for monitoring the temperature variation in both proposed sandwich wall panel and conventional concrete wall panel under a heat radiation source. For further understanding the thermal effect of such sandwich wall panel design from building scale, two three-story building models adopting different wall panel designs are constructed for evaluating the temperature distribution of entire buildings using finite element method. Both the experimental and simulation results have shown that the gypsum layer improves the thermal insulation performance by retarding the heat transfer across the building envelopes. PMID:25177718

  1. The cell wall: a carbohydrate armour for the fungal cell.

    Science.gov (United States)

    Latgé, Jean-Paul

    2007-10-01

    The cell wall is composed of a polysaccharide-based three-dimensional network. Considered for a long time as an inert exoskeleton, the cell wall is now seen as a dynamic structure that is continuously changing as a result of the modification of culture conditions and environmental stresses. Although the cell wall composition varies among fungal species, chemogenomic comparative analysis have led to a better understanding of the genes and mechanisms involved in the construction of the common central core composed of branched beta1,3 glucan-chitin. Because of its essential biological role, unique biochemistry and structural organization and the absence in mammalian cells of most of its constitutive components, the cell wall is an attractive target for the development of new antifungal agents. Genomic as well as drug studies have shown that the death of the fungus can result from inhibition of cell wall polysaccharide synthases. To date, only beta1,3 glucan synthase inhibitors have been launched clinically and many more targets remain to be explored.

  2. Reconsolidated Salt as a Geotechnical Barrier

    International Nuclear Information System (INIS)

    Hansen, Francis D.; Gadbury, Casey

    2015-01-01

    Salt as a geologic medium has several attributes favorable to long-term isolation of waste placed in mined openings. Salt formations are largely impermeable and induced fractures heal as stress returns to equilibrium. Permanent isolation also depends upon the ability to construct geotechnical barriers that achieve nearly the same high-performance characteristics attributed to the native salt formation. Salt repository seal concepts often include elements of reconstituted granular salt. As a specific case in point, the Waste Isolation Pilot Plant recently received regulatory approval to change the disposal panel closure design from an engineered barrier constructed of a salt-based concrete to one that employs simple run-of-mine salt and temporary bulkheads for isolation from ventilation. The Waste Isolation Pilot Plant is a radioactive waste disposal repository for defense-related transuranic elements mined from the Permian evaporite salt beds in southeast New Mexico. Its approved shaft seal design incorporates barrier components comprising salt-based concrete, bentonite, and substantial depths of crushed salt compacted to enhance reconsolidation. This paper will focus on crushed salt behavior when applied as drift closures to isolate disposal rooms during operations. Scientific aspects of salt reconsolidation have been studied extensively. The technical basis for geotechnical barrier performance has been strengthened by recent experimental findings and analogue comparisons. The panel closure change was accompanied by recognition that granular salt will return to a physical state similar to the halite surrounding it. Use of run-of-mine salt ensures physical and chemical compatibility with the repository environment and simplifies ongoing disposal operations. Our current knowledge and expected outcome of research can be assimilated with lessons learned to put forward designs and operational concepts for the next generation of salt repositories. Mined salt

  3. Reconsolidated Salt as a Geotechnical Barrier

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Francis D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gadbury, Casey [USDOE Carlsbad Field Office, NM (United States)

    2015-11-01

    Salt as a geologic medium has several attributes favorable to long-term isolation of waste placed in mined openings. Salt formations are largely impermeable and induced fractures heal as stress returns to equilibrium. Permanent isolation also depends upon the ability to construct geotechnical barriers that achieve nearly the same high-performance characteristics attributed to the native salt formation. Salt repository seal concepts often include elements of reconstituted granular salt. As a specific case in point, the Waste Isolation Pilot Plant recently received regulatory approval to change the disposal panel closure design from an engineered barrier constructed of a salt-based concrete to one that employs simple run-of-mine salt and temporary bulkheads for isolation from ventilation. The Waste Isolation Pilot Plant is a radioactive waste disposal repository for defense-related transuranic elements mined from the Permian evaporite salt beds in southeast New Mexico. Its approved shaft seal design incorporates barrier components comprising salt-based concrete, bentonite, and substantial depths of crushed salt compacted to enhance reconsolidation. This paper will focus on crushed salt behavior when applied as drift closures to isolate disposal rooms during operations. Scientific aspects of salt reconsolidation have been studied extensively. The technical basis for geotechnical barrier performance has been strengthened by recent experimental findings and analogue comparisons. The panel closure change was accompanied by recognition that granular salt will return to a physical state similar to the halite surrounding it. Use of run-of-mine salt ensures physical and chemical compatibility with the repository environment and simplifies ongoing disposal operations. Our current knowledge and expected outcome of research can be assimilated with lessons learned to put forward designs and operational concepts for the next generation of salt repositories. Mined salt

  4. load-displacement and stability characteristics of tidn-walled beams

    African Journals Online (AJOL)

    construction. Such structural ... The finite displacement formulation is used for load- displacement .... The other stress term, which is the incremental linear stress term a/ is .... formulation, only two out of the four general governing ..... 119, Paper. No. 2700 ... Deformations Spatial Buckling of Thin-Walled Beams and Frames ...

  5. Progress in forming bottom barriers under waste sites

    International Nuclear Information System (INIS)

    Carter, E.E.

    1997-01-01

    The paper describes an new method for the construction, verification, and maintenance of underground vaults to isolate and contain radioactive burial sites without excavation or drilling in contaminated areas. The paper begins with a discussion of previous full-scale field tests of horizontal barrier tools which utilized high pressure jetting technology. This is followed by a discussion of the TECT process, which cuts with an abrasive cable instead of high pressure jets. The new method is potentially applicable to more soil types than previous methods and can form very thick barriers. Both processes are performed from the perimeter of a site and require no penetration or disturbance of the active waste area. The paper also describes long-term verification methods to monitor barrier integrity passively

  6. Tritium permeation barriers for fusion technology

    International Nuclear Information System (INIS)

    Perujo, A.; Forcey, K.

    1994-01-01

    An important issue concerning the safety, feasibility and fueling (i.e., tritium breeding ratio and recovery from the breeding blanket) of a fusion reactor is the possible tritium leakages through the structural materials and in particular through those operating at high temperatures. The control of tritium permeation could be a critical factor in determining the viability of a future fusion power reactor. The formation of tritium permeation barriers to prevent the loss of tritium to the coolant by diffusion though the structural material seems to be the most practical method to minimize such losses. Many authors have discussed the formation of permeation barriers to reduce the leakage of hydrogen isotopes through proposed first wall and structural materials. In general, there are two routes for the formation of such a barrier, namely: the growth of oxide layers (e.g., Cr 2 O 3 , Al 2 O 3 , etc.) or the application of surface coatings. Non-metals are the most promising materials from the point of view of the formation of permeation barriers. Oxides such as Al 2 O 3 or Cr 2 O 3 or carbides such as SiC or TiC have been proposed. Amongst the metals only tungsten or gold are sufficiently less permeable than steel to warrant investigation as candidate materials for permeation barriers. It is of course possible to grow oxide layers on steel directly by heating in the atmosphere or under a variety of conditions (first route above). The direct oxidizing is normally done in an environment of open-quotes wet hydrogenclose quotes to promote the growth of chromia on, for example, nickel steels or ternary oxides on 316L to prevent corrosion. The application of surface layers (second route above), offers a greater range of materials for the formation of permeation barriers. In addition to reducing permeation, such layers should be adhesive, resistant to attack by corrosive breeder materials and should not crack during thermal cycling

  7. Experimental evaluation of the prevention methods for the interface between masonry infill walls and concrete columns

    Directory of Open Access Journals (Sweden)

    A. P. Tramontin

    Full Text Available Cracks that form at the interfaces between masonry structures are common uncontrolled occurrences in buildings. Numerous methods have been proposed by the construction industry to address this problem. Cracks continuously form in the joints between concrete columns and masonry infill walls. In this study, the most common methods for preventing these types of cracks were evaluated in laboratory experiments. Column masonry models were constructed using different types of joints between concrete columns and masonry infill walls, such as steel bars and steel mesh. The efficiency of each type of joint method was evaluated by performing direct tensile tests (pullout tests on the models and monitoring the evolution of the crack opening in the joint between the column and wall, as a function of load applied to the model. The results from this study indicate that the model composed of "electrowelded wire mesh without steel angles" is the best model for controlling cracking in the joints between concrete columns and masonry infill walls.

  8. Performance of Screen Grid Insulating Concrete Form Walls under Combined In-Plane Vertical and Lateral Loads

    KAUST Repository

    Abdel Mooty, Mohamed; Haroun, Medhat; El Maghraby, Yosra; Fahmy, Ezzat; Abou Zeid, Mohamed

    2010-01-01

    advantages over traditional methods of wall construction such as reduced construction time, noise reduction, strength enhancement, energy efficiency, and compatibility with any inside or outside surface finish. The focus of this study is the Screen Grid ICF

  9. How the deposition of cellulose microfibrils builds cell wall architecture

    NARCIS (Netherlands)

    Emons, A.M.C.; Mulder, B.M.

    2000-01-01

    Cell walls, the extracytoplasmic matrices of plant cells, consist of an ordered array of cellulose microfibrils embedded in a matrix of polysaccharides and glycoproteins. This construction is reminiscent of steel rods in reinforced concrete. How a cell organizes these ordered textures around itself,

  10. Determination of strength behaviour of slope supported by vegetated crib walls using centrifuge model testing

    Science.gov (United States)

    Sudan Acharya, Madhu

    2010-05-01

    The crib retaining structures made of wooden/bamboo logs with live plants inside are called vegetative crib walls which are now becoming popular due to their advantages over conventional civil engineering walls. Conventionally, wooden crib walls were dimensioned based on past experiences. At present, there are several guidelines and design standards for machine finished wooden crib walls, but only few guidelines for the design and construction of vegetative log crib walls are available which are generally not sufficient for an economic engineering design of such walls. Analytical methods are generally used to determine the strength of vegetated crib retaining walls. The crib construction is analysed statically by satisfying the condition of static equilibrium with acceptable level of safety. The crib wall system is checked for internal and external stability using conventional monolithic and silo theories. Due to limitations of available theories, the exact calculation of the strength of vegetated wooden/bamboo crib wall cannot be made in static calculation. Therefore, experimental measurements are generally done to verify the static analysis. In this work, a model crib construction (1:20) made of bamboo elements is tested in the centrifuge machine to determine the strength behaviour of the slope supported by vegetated crib retaining wall. A geotechnical centrifuge is used to conduct model tests to study geotechnical problems such as the strength, stiffness and bearing capacity of different structures, settlement of embankments, stability of slopes, earth retaining structures etc. Centrifuge model testing is particularly well suited to modelling geotechnical events because the increase in gravitational force creates stresses in the model that are equivalent to the much larger prototype and hence ensures that the mechanisms of ground movements observed in the tests are realistic. Centrifuge model testing provides data to improve our understanding of basic mechanisms

  11. A computational fluid dynamics modeling study of guide walls for downstream fish passage

    Science.gov (United States)

    Mulligan, Kevin; Towler, Brett; Haro, Alexander J.; Ahlfeld, David P.

    2017-01-01

    A partial-depth, impermeable guidance structure (or guide wall) for downstream fish passage is typically constructed as a series of panels attached to a floating boom and anchored across a water body (e.g. river channel, reservoir, or power canal). The downstream terminus of the wall is generally located nearby to a fish bypass structure. If guidance is successful, the fish will avoid entrainment in a dangerous intake structure (i.e. turbine intakes) while passing from the headpond to the tailwater of a hydroelectric facility through a safer passage route (i.e. the bypass). The goal of this study is to determine the combination of guide wall design parameters that will most likely increase the chance of surface-oriented fish being successfully guided to the bypass. To evaluate the flow field immediately upstream of a guide wall, a parameterized computational fluid dynamics model of an idealized power canal was constructed in © ANSYS Fluent v 14.5 (ANSYS Inc., 2012). The design parameters investigated were the angle and depth of the guide wall and the average approach velocity in the power canal. Results call attention to the importance of the downward to sweeping flow ratio and demonstrate how a change in guide wall depth and angle can affect this important hydraulic cue to out-migrating fish. The key findings indicate that a guide wall set at a small angle (15° is the minimum in this study) and deep enough such that sweeping flow dominant conditions prevail within the expected vertical distribution of fish approaching the structure will produce hydraulic conditions that are more likely to result in effective passage.

  12. Method of detecting construction faults in concrete pressure vessels

    International Nuclear Information System (INIS)

    Robertson, S.A.; Duhoux, M.; Dawance, G.; Carrie, C.; Morel, D.

    1976-01-01

    A major problem in the design and construction of concrete pressure vessels for nuclear power stations is the risk of excessive air leaks through the concrete itself, due to faulty construction. The 'sonic coring' method of non-destructive concrete testing has been used successfully in pile and diaphragm wall construction control for several years, and the potential use of this method to control the presence of faults in concrete pressure vessels is here described. (author)

  13. Impact of cell wall encapsulation of almonds on in vitro duodenal lipolysis.

    Science.gov (United States)

    Grundy, Myriam M L; Wilde, Peter J; Butterworth, Peter J; Gray, Robert; Ellis, Peter R

    2015-10-15

    Although almonds have a high lipid content, their consumption is associated with reduced risk of cardiovascular disease. One explanation for this paradox could be limited bioaccessibility of almond lipids due to the cell wall matrix acting as a physical barrier to digestion in the upper gastrointestinal tract. We aimed to measure the rate and extent of lipolysis in an in vitro duodenum digestion model, using raw and roasted almond materials with potentially different degrees of bioaccessibility. The results revealed that a decrease in particle size led to an increased rate and extent of lipolysis. Particle size had a crucial impact on lipid bioaccessibility, since it is an indicator of the proportion of ruptured cells in the almond tissue. Separated almond cells with intact cell walls showed the lowest levels of digestibility. This study underlines the importance of the cell wall for modulating lipid uptake and hence the positive health benefits underlying almond consumption. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Urban parks as green walls or green magnets? Interracial relations in neighborhood boundary parks

    Science.gov (United States)

    Paul H. Gobster

    1998-01-01

    A recent paper in this journal (Solecki and Welch, 1995) describes how urban parks that lie between racially different neighborhoods can become "green walls" or barriers to use and appreciation. Although this phenomenon is well grounded in the experience of many who plan for, manage, and live near parks in racially and ethnically segregated cities, an...

  15. Behavior of thin-walled beams made of advanced composite materials and incorporating non-classical effects

    Science.gov (United States)

    Librescu, Liviu; Song, Ohseop

    1991-11-01

    Several results concerning the refined theory of thin-walled beams of arbitrary closed cross-section incorporating nonclassical effects are presented. These effects are related both with the exotic properties characterizing the advanced composite material structures and the nonuniform torsional model. A special case of the general equations is used to study several problems of cantilevered thin-walled beams and to assess the influence of the incorporated effects. The results presented in this paper could be useful toward a more rational design of aeronautical or aerospace constructions, as well as of helicopter or tilt rotor blades constructed of advanced composite materials.

  16. Small scale structure in the wall region of a turbulent boundary layer

    International Nuclear Information System (INIS)

    Bogar, T.J.

    1975-01-01

    This paper is a report of the construction and application of an extremely small hot-wire X-probe (typical dimensions of 100 μ) to the measurement of Reynolds stress in the wall region of the turbulent boundary layer of a flat plate at high Reynolds number (Re/sub theta/ = 11,300). In the present flow, the size of the probe corresponds to a dimensionless length based on wall parameters of lu/sub tau//ν = 3. Probe construction methods are described. The Wyngaard-Lumley constant temperature anemometer used to heat the wire is analyzed, and a direct acoustical frequency calibration of the wire is made. This calibration shows the small wire to have uniform frequency response to 15 kHz. A novel calibration technique is employed using a high speed, digital mini-computer to determine the velocity in the stream direction and in a direction normal to the wall by matching the unique voltage pairs produced by the X-wire array in a turbulent flow to the voltage pairs produced when the probe is exposed to a known uniform flow inclined at various angles

  17. Development of full scale testing of an alternate foundation system for post and panel retaining walls.

    Science.gov (United States)

    2009-03-01

    The alternate post system offers benefits such as ease of construction, reduced construction time, and : lower wall costs. While this system seems feasible, there are concerns regarding its performance, in : particular the amount of bending in the po...

  18. Impact effects in thin-walled structures

    International Nuclear Information System (INIS)

    Zukas, J.A.; Gaskill, B.

    1996-01-01

    A key parameter in the design of protective structures is the critical impact velocity, also known as the ballistic limit. This is the velocity below which a striker will fail to penetrate a barrier or some protective device. For strikers with regular shapes, such as cylinders (long and short), spheres and cones, analytical and empirical formulations for the determination of a ballistic limit exist at impact velocities ranging from 250 m/s to 6 km/s or higher. For non-standard shapes, two- and three-dimensional wave propagation codes (hydrocodes) can be valuable adjuncts to experiments in ballistic limit determinations. This is illustrated with the help of the ZeuS code in determining the ballistic limit of a short, tubular projectile striking a thin aluminum barrier and contrasting it to the value of the ballistic limit of a spherical projectile of equal mass against the same target. Several interesting features of the debris cloud generated by a tubular projectile striking a Whipple shield at hypervelocity are also pointed out. The paper concludes with a consideration of hydrodynamic ram effects in fluid-filled thin-walled structures. Where possible, comparisons are made of computed results with experimental data

  19. Development of a Framework for Attracting and Retaining Women in Construction Practice

    Directory of Open Access Journals (Sweden)

    K.J. Adogbo

    2015-01-01

    Full Text Available Previous research has indicated that women are significantly under-represented in the Nigerian construction industry and that female undergraduates face barriers that deter them from engaging in construction practice. This research examined the barriers faced by female undergraduates in the construction disciplines at Nigerian Universities. The research adopted the use of a questionnaire and semi-structured interviews. A total of 360 questionnaires were distributed, and 259 (71.94% were returned and used in the analysis. The semi-structured interviews were conducted with 50 female students and 16 women across the professions of Architecture, Building, Civil Engineering and Quantity Surveying. The results revealed that the undergraduates perceived the construction practice to be synonymous with site activities and that family responsibility posed the greatest barrier to their participation. The strategies identified by the women in practice included active participation in the activity of professional bodies and seeking a mentor. It was concluded that female graduates can be attracted to the industry, but efforts need to be put in place to successfully implement the strategies identified by the professional women. A framework that addresses gender issues in attracting and retaining graduates in the construction practice was developed to help women plan their career in the industry.

  20. SoilSaw trademark demonstration. Final report, September 1992--January 1995

    International Nuclear Information System (INIS)

    Saugier, K.; Isaac, R.E.

    1996-02-01

    The US Department of Energy (DOE) has identified leaking underground storage tanks and buried mixed waste at numerous sites within the DOE complex. Preventing these wastes from entering the environment is a challenging task. One method of preventing waste migration is to isolate the contaminants using subsurface containment barriers. Isolation and containment can be accomplished by both in situ and ex situ methods. This report describes a novel in situ construction method of forming vertical containment barriers (slurry walls) using the SoilSaw trademark Barrier System. The SoilSaw trademark Barrier System is shown to be a feasible process for constructing subsurface vertical containment barriers to depths of fifty feet. The process is most efficient in sandy soil (including free flowing sand) with barrier construction rates of over 130 square feet per minute. Productivity diminishes to approximately 30 square feet per minute as soils become harder and more cohesive. The present hardware is designed to form a barrier of approximately 12 inch in width. Additional barrier widths can be constructed with this technology by application of wider jet heads. The requirement for a varied arrangement of barrier widths is an increase in hydraulic horse power and additional jet heads

  1. SoilSaw{trademark} demonstration. Final report, September 1992--January 1995

    Energy Technology Data Exchange (ETDEWEB)

    Saugier, K.; Isaac, R.E.

    1996-02-01

    The US Department of Energy (DOE) has identified leaking underground storage tanks and buried mixed waste at numerous sites within the DOE complex. Preventing these wastes from entering the environment is a challenging task. One method of preventing waste migration is to isolate the contaminants using subsurface containment barriers. Isolation and containment can be accomplished by both in situ and ex situ methods. This report describes a novel in situ construction method of forming vertical containment barriers (slurry walls) using the SoilSaw{trademark} Barrier System. The SoilSaw{trademark} Barrier System is shown to be a feasible process for constructing subsurface vertical containment barriers to depths of fifty feet. The process is most efficient in sandy soil (including free flowing sand) with barrier construction rates of over 130 square feet per minute. Productivity diminishes to approximately 30 square feet per minute as soils become harder and more cohesive. The present hardware is designed to form a barrier of approximately 12 inch in width. Additional barrier widths can be constructed with this technology by application of wider jet heads. The requirement for a varied arrangement of barrier widths is an increase in hydraulic horse power and additional jet heads.

  2. Structure reconstruction of TiO2-based multi-wall nanotubes: first-principles calculations.

    Science.gov (United States)

    Bandura, A V; Evarestov, R A; Lukyanov, S I

    2014-07-28

    A new method of theoretical modelling of polyhedral single-walled nanotubes based on the consolidation of walls in the rolled-up multi-walled nanotubes is proposed. Molecular mechanics and ab initio quantum mechanics methods are applied to investigate the merging of walls in nanotubes constructed from the different phases of titania. The combination of two methods allows us to simulate the structures which are difficult to find only by ab initio calculations. For nanotube folding we have used (1) the 3-plane fluorite TiO2 layer; (2) the anatase (101) 6-plane layer; (3) the rutile (110) 6-plane layer; and (4) the 6-plane layer with lepidocrocite morphology. The symmetry of the resulting single-walled nanotubes is significantly lower than the symmetry of initial coaxial cylindrical double- or triple-walled nanotubes. These merged nanotubes acquire higher stability in comparison with the initial multi-walled nanotubes. The wall thickness of the merged nanotubes exceeds 1 nm and approaches the corresponding parameter of the experimental patterns. The present investigation demonstrates that the merged nanotubes can integrate the two different crystalline phases in one and the same wall structure.

  3. Ab initio transport across bismuth selenide surface barriers

    KAUST Repository

    Narayan, Awadhesh

    2014-11-24

    © 2014 American Physical Society. We investigate the effect of potential barriers in the form of step edges on the scattering properties of Bi2Se3(111) topological surface states by means of large-scale ab initio transport simulations. Our results demonstrate the suppression of perfect backscattering, while all other scattering processes, which do not entail a complete spin and momentum reversal, are allowed. Furthermore, we find that the spin of the surface state develops an out-of-plane component as it traverses the barrier. Our calculations reveal the existence of quasibound states in the vicinity of the surface barriers, which appear in the form of an enhanced density of states in the energy window corresponding to the topological state. For double barriers we demonstrate the formation of quantum well states. To complement our first-principles results we construct a two-dimensional low-energy effective model and illustrate its shortcomings. Our findings are discussed in the context of a number of recent experimental works.

  4. From The Sea Wall to The Lover : Prostitution and Exotic Parody

    Directory of Open Access Journals (Sweden)

    Pascale Bécel

    1997-06-01

    Full Text Available This analysis of the two novels highlights Marguerite Duras' equivocal stance with regard to colonial Indochina where she grew up at the beginning of the century. As The Lover rewrites The Sea Wall in the autobiographical mode, the emphasis shifts from an explicit denunciation of colonialism and an implicit subversion of the Lotilian novel, to a parody of exotic themes and narratives. However, by focusing on the two young protagonists' construction of themselves as femmes fatales and prostitutes, this discussion reveals that the politics of gender and race remain at odds in Duras' fictional autobiographies. The cultural other (qua a passive indigenous population in The Sea Wall , qua eroticized oriental[ized] bodies in The Lover remains a measure of the protagonist's construction as a female subject; a measure, in Chandra Mohanty's words, of the "liberated" western woman's "discursive self-presentation."

  5. A drift chamber constructed of aluminized mylar tubes

    Science.gov (United States)

    Baringer, P.; Jung, C.; Ogren, H. O.; Rust, D. R.

    1987-03-01

    A thin reliable drift chamber has been constructed to be used near the interaction point of the PEP storage ring in the HRS detector. It is composed of individual drift tubes with aluminized mylar walls.

  6. Construction of a 2- by 2-foot transonic adaptive-wall test section at the NASA Ames Research Center

    Science.gov (United States)

    Morgan, Daniel G.; Lee, George

    1986-01-01

    The development of a new production-size, two-dimensional, adaptive-wall test section with ventilated walls at the NASA Ames Research Center is described. The new facility incorporates rapid closed-loop operation, computer/sensor integration, and on-line interference assessment and wall corrections. Air flow through the test section is controlled by a series of plenum compartments and three-way slide vales. A fast-scan laser velocimeter was built to measure velocity boundary conditions for the interference assessment scheme. A 15.2-cm- (6.0-in.-) chord NACA 0012 airfoil model will be used in the first experiments during calibration of the facility.

  7. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    Dwyer, B.P.; Heiser, J.; Stewart, W.

    1996-01-01

    The primary objective of this project is to develop and demonstrate a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification

  8. Buffer Construction Methodology in Demonstration Test For Cavern Type Disposal Facility

    International Nuclear Information System (INIS)

    Yoshihiro, Akiyama; Takahiro, Nakajima; Katsuhide, Matsumura; Kenji, Terada; Takao, Tsuboya; Kazuhiro, Onuma; Tadafumi, Fujiwara

    2009-01-01

    A number of studies concerning a cavern type disposal facility have been carried out for disposal of low level radioactive waste mainly generated by power plant decommissioning in Japan. The disposal facility is composed of an engineered barrier system with concrete pit and bentonite buffer, and planed to be constructed in sub-surface 50 - 100 meters depth. Though the previous studies have mainly used laboratory and mock-up tests, we conducted a demonstration test in a full-size cavern. The main objectives of the test were to study the construction methodology and to confirm the quality of the engineered barrier system. The demonstration test was planned as the construction of full scale mock-up. It was focused on a buffer construction test to evaluate the construction methodology and quality control in this paper. Bentonite material was compacted to 1.6 Mg/m 3 in-site by large vibrating roller in this test. Through the construction of the buffer part, a 1.6 Mg/m 3 of the density was accomplished, and the data of workability and quality is collected. (authors)

  9. Acoustic microstreaming due to an ultrasound contrast microbubble near a wall

    Science.gov (United States)

    Mobadersany, Nima; Sarkar, Kausik

    2017-11-01

    In an ultrasound field, in addition to the sinusoidal motion of fluid particles, particles experience a steady streaming velocity due to nonlinear second order effects. Here, we have simulated the microstreaming flow near a plane rigid wall caused by the pulsations of contrast microbubbles. Although these microbubbles were initially developed as a contrast enhancing agents for ultrasound imaging, they generate additional therapeutic effects that can be harnessed for targeted drug delivery or blood brain barrier (BBB) opening. The microbubbles have a gas core coated with a stabilizing layer of lipids or proteins. We use analytical models as well as boundary element (BEM) simulation to simulate the flow around these bubbles implementing interfacial rheology models for the coating. The microstreaming flow is characterized by two wall bounded vortices. The size of the vortices decreases with the decrease of the separation from the wall. The vortex-induced shear stress is simulated and analyzed as a function of excitation parameters and geometry. These microstreaming shear stress plays a critical role in increasing the membrane permeability facilitating drug delivery or rupturing biological tissues.

  10. Effects of opening in shear walls of 30- storey building

    Directory of Open Access Journals (Sweden)

    Ruchi Sharma

    2015-03-01

    Full Text Available Tall towers and multi-storey buildings have fascinated mankind from the beginning of civilization, their construction being initially for defense and subsequently for ecclesiastical purposes. These tall buildings because of its height, is affected by lateral forces due to wind or earthquake actions tends to snap the building in shear and push it over in bending. In general, the rigidity (i.e. Resistance to lateral deflection and stability (i.e. Resistance to overturning moments requirement become more important. Shear walls (Structural walls contribute significant lateral stiffness, strength, and overall ductility and energy dissipation capacity. In many structural walls a regular pattern of openings has to be provided due to various functional requirements such as to accommodate doors, windows and service ducts. Such type of openings reduces the stiffness of the shear wall to some extent depending on the shape and size of the opening. In the present parametric study, efforts are made to investigate and critically assess the effects of various size of openings in shear walls on the responses and behaviors of multi-storey buildings. The 30 storey Prototype buildings with different types of openings in shear wall with and without incorporating the volume of shear wall reduced in the boundary elements are analyzed using software E-TABS using Response spectrum method (1893(Part-1-2002 and Time history method.

  11. Another Concrete In the Wall

    OpenAIRE

    Meric, Asli Duru

    2015-01-01

    concrete has a memory. It stores the construction sequences. It shows what it is made of and how it is made. The texture of the formwork, the color difference of the pours, and the shadows of the metal ties combine to layer the beauty of concrete. The aim of this study is to explore the instruments of a concrete surface in order to enhance this multi-sensory experience. This study began with the design of a concrete wall and evolved into the design of a single-family home. MARCH

  12. A drift chamber constructed of aluminized mylar tubes

    International Nuclear Information System (INIS)

    Baringer, P.; Jung, C.; Ogren, H.O.; Rust, D.R.

    1987-01-01

    A thin reliable drift chamber has been constructed to be used near the interaction point of the PEP storage ring in the HRS detector. It is composed of individual drift tubes with aluminized mylar walls. (orig.)

  13. Overview and Design Considerations of Storm Surge Barriers

    NARCIS (Netherlands)

    Mooyaart, L.F.; Jonkman, S.N.

    2017-01-01

    The risk of flooding in coastal zones is expected to increase due to sea level rise and economic development. In larger bays, estuaries, and coastal waterways, storm surge barriers can be constructed to temporarily close off these systems during storm surges to provide coastal flood protection.

  14. Cancer cells remodel themselves and vasculature to overcome the endothelial barrier.

    Science.gov (United States)

    Shenoy, Anitha K; Lu, Jianrong

    2016-10-01

    Metastasis refers to the spread of cancer cells from a primary tumor to distant organs mostly via the bloodstream. During the metastatic process, cancer cells invade blood vessels to enter circulation, and later exit the vasculature at a distant site. Endothelial cells that line blood vessels normally serve as a barrier to the movement of cells into or out of the blood. It is thus critical to understand how metastatic cancer cells overcome the endothelial barrier. Epithelial cancer cells acquire increased motility and invasiveness through epithelial-to-mesenchymal transition (EMT), which enables them to move toward vasculature. Cancer cells also express a variety of adhesion molecules that allow them to attach to vascular endothelium. Finally, cancer cells secrete or induce growth factors and cytokines to actively prompt vascular hyperpermeability that compromises endothelial barrier function and facilitates transmigration of cancer cells through the vascular wall. Elucidation of the mechanisms underlying metastatic dissemination may help develop new anti-metastasis therapeutics. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Role of structural barriers for carotenoid bioaccessibility upon high pressure homogenization.

    Science.gov (United States)

    Palmero, Paola; Panozzo, Agnese; Colle, Ines; Chigwedere, Claire; Hendrickx, Marc; Van Loey, Ann

    2016-05-15

    A specific approach to investigate the effect of high pressure homogenization on the carotenoid bioaccessibility in tomato-based products was developed. Six different tomato-based model systems were reconstituted in order to target the specific role of the natural structural barriers (chromoplast substructure/cell wall) and of the phases (soluble/insoluble) in determining the carotenoid bioaccessibility and viscosity changes upon high pressure homogenization. Results indicated that in the absence of natural structural barriers (carotenoid enriched oil), the soluble and insoluble phases determined the carotenoid bioaccessibility upon processing whereas, in their presence, these barriers governed the bioaccessibility. Furthermore, it was shown that the increment of the viscosity upon high pressure homogenization is determined by the presence of insoluble phase, however, this result was related to the initial ratio of the soluble:insoluble phases in the system. In addition, no relationship between the changes in viscosity and carotenoid bioaccessibility upon high pressure homogenization was found. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Analysis of the eukaryotic community and metabolites found in clay wall material used in the construction of traditional Japanese buildings.

    Science.gov (United States)

    Kitajima, Sakihito; Kamei, Kaeko; Nishitani, Maiko; Sato, Hiroyuki

    2010-01-01

    Clay wall (tsuchikabe in Japanese) material for Japanese traditional buildings is manufactured by fermenting a mixture of clay, sand, and rice straw. The aim of this study was to understand the fermentation process in order to gain insight into the ways waste biomass can be used to produce useful materials. In this study, in addition to Clostridium, we suggested that the family Nectriaceae and the Scutellinia sp. of fungi were important in degrading cell wall materials of rice straw, such as cellulose and/or lignin. The microorganisms in the clay wall material produced sulfur-containing inorganic compounds that may sulfurate minerals in clay particles, and polysaccharides that give viscosity to clay wall material, thus increasing workability for plastering, and possibly giving water-resistance to the dried clay wall.

  17. Pseudo-dynamic tests on masonry residential buildings seismically retrofitted by precast steel reinforced concrete walls

    Science.gov (United States)

    Li, Wenfeng; Wang, Tao; Chen, Xi; Zhong, Xiang; Pan, Peng

    2017-07-01

    A retrofitting technology using precast steel reinforced concrete (PSRC) panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.

  18. Humidity Distributions in Multilayered Walls of High-rise Buildings

    Science.gov (United States)

    Gamayunova, Olga; Musorina, Tatiana; Ishkov, Alexander

    2018-03-01

    The limitation of free territories in large cities is the main reason for the active development of high-rise construction. Given the large-scale projects of high-rise buildings in recent years in Russia and abroad and their huge energy consumption, one of the fundamental principles in the design and reconstruction is the use of energy-efficient technologies. The main heat loss in buildings occurs through enclosing structures. However, not always the heat-resistant wall will be energy-efficient and dry at the same time (perhaps waterlogging). Temperature and humidity distributions in multilayer walls were studied in the paper, and the interrelation of other thermophysical characteristics was analyzed.

  19. Dynamical correlations for vicious random walk with a wall

    International Nuclear Information System (INIS)

    Nagao, Taro

    2003-01-01

    A one-dimensional system of nonintersecting Brownian particles is constructed as the diffusion scaling limit of Fisher's vicious random walk model. N Brownian particles start from the origin at time t=0 and undergo mutually avoiding motion until a finite time t=T. Dynamical correlation functions among the walkers are exactly evaluated in the case with a wall at the origin. Taking an asymptotic limit N→∞, we observe discontinuous transitions in the dynamical correlations. It is further shown that the vicious walk model with a wall is equivalent to a parametric random matrix model describing the crossover between the Bogoliubov-deGennes universality classes

  20. Through-Metal-Wall Power Delivery and Data Transmission for Enclosed Sensors: A Review

    Directory of Open Access Journals (Sweden)

    Ding-Xin Yang

    2015-12-01

    Full Text Available The aim of this review was to assess the current viable technologies for wireless power delivery and data transmission through metal barriers. Using such technologies sensors enclosed in hermetical metal containers can be powered and communicate through exterior power sources without penetration of the metal wall for wire feed-throughs. In this review, we first discuss the significant and essential requirements for through-metal-wall power delivery and data transmission and then we: (1 describe three electromagnetic coupling based techniques reported in the literature, which include inductive coupling, capacitive coupling, and magnetic resonance coupling; (2 present a detailed review of wireless ultrasonic through-metal-wall power delivery and/or data transmission methods; (3 compare various ultrasonic through-metal-wall systems in modeling, transducer configuration and communication mode with sensors; (4 summarize the characteristics of electromagnetic-based and ultrasound-based systems, evaluate the challenges and development trends. We conclude that electromagnetic coupling methods are suitable for through thin non-ferromagnetic metal wall power delivery and data transmission at a relatively low data rate; piezoelectric transducer-based ultrasonic systems are particularly advantageous in achieving high power transfer efficiency and high data rates; the combination of more than one single technique may provide a more practical and reliable solution for long term operation.

  1. Interactions of the cell-wall glycopolymers of lactic acid bacteria with their bacteriophages

    Directory of Open Access Journals (Sweden)

    Marie-Pierre eChapot-Chartier

    2014-05-01

    Full Text Available Lactic acid bacteria (LAB are Gram positive bacteria widely used in the production of fermented food in particular cheese and yoghurts. Bacteriophage infections during fermentation processes have been for many years a major industrial concern and have stimulated numerous research efforts. Better understanding of the molecular mechanisms of bacteriophage interactions with their host bacteria is required for the development of efficient strategies to fight against infections. The bacterial cell wall plays key roles in these interactions. First, bacteriophages must adsorb at the bacterial surface through specific interactions with receptors that are cell wall components. At next step, phages must overcome the barrier constituted by cell wall peptidoglycan to inject DNA inside bacterial cell. Also at the end of the infection cycle, phages synthesize endolysins able to hydrolyze peptidoglycan and lyse bacterial cells to release phage progeny. In the last decade, concomitant development of genomics and structural analysis of cell wall components allowed considerable advances in the knowledge of their structure and function in several model LAB. Here, we describe the present knowledge on the structure of the cell wall glycopolymers of the best characterized LAB emphasizing their structural variations and we present the available data regarding their role in bacteria-phage specific interactions at the different steps of the infection cycle.

  2. Frost as a first wall for the ICF laboratory microfusion facility

    International Nuclear Information System (INIS)

    Orth, C.D.

    1989-01-01

    The authors introduce the concept of using frost as the first wall of the ICF Laboratory Microfusion Facility being designed to produce 200-1000 MJ of thermonuclear yield. They present one design incorporating 2cm of frost deposited at 0.1 g/cm/sup 3/ on an LN-cooled fiber-reinforced polymer substrate. They calculate that such a frost layer will protect the substrate from ablation by target x rays and debris, and from shock-induced spallation. Postshot washdown with water should permit low-activation operation, and should preserve the original wall properties. The authors expect the impact of the frost on laser optics to be minimal, and expect the preshot lifetime of thermally unprotected cryogenic targets to be extended by operating the wall at 100-150 K. Moreover, they believe that such a frost first wall involves little technical risk, and will be inexpensive to construct and operate

  3. Frost as a first wall for the ICF Laboratory Microfusion Facility

    International Nuclear Information System (INIS)

    Orth, C.D.

    1988-01-01

    We introduce the concept of using frost as the first wall of the ICF Laboratory Microfusion Facility being designed to produce 200--1000 MJ of thermonuclear yield. We present one design incorporating 2 cm of frost deposited at 0.1 g/cm 3 on an LN-cooled fiber-reinforced polymer substrate. We calculate that such a frost layer will protect the substrate from ablation by target x rays and debris, and from shock-induced spallation. Postshot washdown with water should permit low-activation operation, and should preserve the original wall properties. We expect the impact of the frost on laser optics to be minimal, and expect the preshot lifetime of thermally unprotected cryogenic targets to be extended by operating the wall at 100-150 K. Moreover, we believe that such a frost first wall will involve little technical risk, and will be inexpensive to construct and operate. 4 refs., 1 fig

  4. Nonlinear Analyses of Adobe Masonry Walls Reinforced with Fiberglass Mesh

    Directory of Open Access Journals (Sweden)

    Vincenzo Giamundo

    2014-02-01

    Full Text Available Adobe constructions were widespread in the ancient world, and earth was one of the most used construction materials in ancient times. Therefore, the preservation of adobe structures, especially against seismic events, is nowadays an important structural issue. Previous experimental tests have shown that the ratio between mortar and brick mechanical properties (i.e., strength, stiffness and elastic modulus influences the global response of the walls in terms of strength and ductility. Accurate analyses are presented in both the case of unreinforced and reinforced with fiberglass mesh when varying the mechanical properties of the materials composing the adobe masonry structure. The main issues and variability in the behavior of seismic resisting walls when varying the mechanical properties are herein highlighted. The aim of the overall research activity is to improve the knowledge about the structural behavior of adobe structural members unreinforced and reinforced with fiberglass mesh inside horizontal mortar joints.

  5. Zero carbon homes: Perceptions from the UK construction industry

    International Nuclear Information System (INIS)

    Heffernan, Emma; Pan, Wei; Liang, Xi; Wilde, Pieter de

    2015-01-01

    The take-up of the many voluntary energy efficiency standards which exist in the UK and internationally has been limited. As a result, governments have recognised the need to introduce mandatory schemes through legislation, e.g. from 2016 all new build homes in the UK will be required to achieve zero carbon in regulated energy consumption. However, as 2016 approaches, very few zero carbon homes are being delivered. This paper explores the drivers and barriers for zero carbon homebuilding. The perceptions of the wider construction industry were gathered through a series of semi-structured interviews with professionals involved in commissioning, designing, constructing and regulating housing. The results show that, whilst drivers for zero carbon homebuilding exist, the barriers are currently perceived to be greater than the drivers. The barriers are categorised into five groups: economic, skills and knowledge, industry, legislative and cultural. Mechanisms for policy and industry support for the delivery of zero carbon homes are identified to address these barriers. The research findings highlight the need for a clear and robust policy framework for the forthcoming standard. The Government and industry must prioritise raising public awareness of the need for and benefits of zero carbon homes to help develop market demand. - Highlights: • The strongest drivers were perceived to be in the legislative and economic themes. • More barriers were identified than drivers or potential support mechanisms. • Economic and skills and knowledge barriers were perceived as the most significant. • Uncertainty in zero carbon homes policy is a barrier to zero carbon homebuilding. • Proposed support mechanisms include zero carbon champions and self-build homes

  6. Luminescence dating of anthropogenic features of the San Luis Valley, Colorado: from stone huts to stone walls

    Science.gov (United States)

    Mahan, Shannon; Donlan, Rebecca A.; Kardos, Barbara Maat

    2015-01-01

    The Snake Nest Wall site and the Crestone Stone Huts are in the northern San Luis Valley, Colorado, and provide a unique opportunity to date high-altitude archeological sites of unknown age and origin using optically stimulated luminescence (OSL). We sampled sediment underlying foundation stones of these structures to establish a chronological framework for each site's construction. OSL dating of the quartz grains directly under the Snake Nest Wall suggest that the stones and, therefore, the structure was most recently emplaced between 1855 and 1890 A.D. Dating of the sediment beneath the Crestone Stone Huts suggests the construction time of these huts is between 1860 and 1890 A.D. Analysis of the equivalent dose (DE) dispersion of the OSL samples at Snake Nest Wall and the Crestone Huts shows that the majority of sediments were fully bleached prior to deposition and the low scatter suggests that short-term or shallow alluvial processes were the dominant transport for sediments. In both cases, the OSL ages show that the construction was during very recent historical times, although it is likely that the Snake Nest Wall was rebuilt in the late 19th century. Further study is warranted at the Snake Nest Wall since it shows signs of greater antiquity and a continued presence of human use. The Crestone Huts are shown to be a product of railroad building during the boomtown days of Lucky and Crestone.

  7. Research Advances on Fabricated Shear Wall System

    Science.gov (United States)

    Liu, Xudong; Wang, Donghui; Wang, Sheng; Zhai, Yu

    2018-03-01

    With the rapid development of the construction industry, building energy consumption has been increasing, has become a problem that can not be ignored. It is imperative to develop energy-saving buildings. A new type of prefabricated shear wall is assembled and partially assembled by prefabricated parts, and some concrete is spliced together. The new structure has good integrity, seismic resistance and excellent energy saving and environmental protection performance. It reduces building energy consumption to a great extent. Therefore, the design method, manufacturing process, site assembly process and key technical problems of the system are discussed. For the construction industry gradually entered the energy conservation, environmental protection, safety and durability of sustainable development laid the foundation.

  8. Deletion of admB gene encoding a fungal ADAM affects cell wall construction in Aspergillus oryzae.

    Science.gov (United States)

    Kobayashi, Takuji; Maeda, Hiroshi; Takeuchi, Michio; Yamagata, Youhei

    2017-05-01

    Mammals possess a unique signaling system based on the proteolytic mechanism of a disintegrin and metalloproteinases (ADAMs) on the cell surface. We found two genes encoding ADAMs in Aspergillus oryzae and named them admA and admB. We produced admA and admB deletion strains to elucidate their biological function and clarify whether fungal ADAMs play a similar role as in mammals. The ∆admA∆admB and ∆admB strains were sensitive to cell wall-perturbing agents, congo red, and calcofluor white. Moreover, the two strains showed significantly increased weights of total alkali-soluble fractions from the mycelial cell wall compared to the control strain. Furthermore, ∆admB showed MpkA phosphorylation at lower concentration of congo red stimulation than the control strain. However, the MpkA phosphorylation level was not different between ∆admB and the control strain without the stimulation. The results indicated that A. oryzae AdmB involved in the cell wall integrity without going through the MpkA pathway.

  9. Industrial robots application in the construction of buildings and structures

    Directory of Open Access Journals (Sweden)

    Verzhbovskiy Gennady

    2017-01-01

    Full Text Available Proposals on the use of modernized industrial robots in the construction of low-rise buildings are formulated. The necessary parameters of such a mechanism are established. The time necessary for building the walls of a two-story house is determined. Features of the robots use on the construction site are described.

  10. Wall shear stress hot film sensor for use in gases

    International Nuclear Information System (INIS)

    Osorio, O D; Silin, N

    2011-01-01

    The purpose of this work is to present the construction and characterization of a wall shear stress hot film sensor for use in gases made with MEMS technology. For this purpose, several associated devices were used, including a constant temperature feedback bridge and a shear stress calibration device that allows the sensor performance evaluation. The sensor design adopted here is simple, economical and is manufactured on a flexible substrate allowing its application to curved surfaces. Stationary and transient wall shear stress tests were carried on by means of the calibration device, determining its performance for different conditions.

  11. Gravitational field of spherical domain wall in higher dimension

    Indian Academy of Sciences (India)

    and examine whether bound orbits are possible or not. This study will be of relevance to the structure formation because it gives some idea about the behaviour of the particles. (created at the early universe) in the gravitational field of the domain walls. Our paper is organized as follows: The basic equations are constructed ...

  12. Thermal and radiation loads on the first wall and divertor plates in the KTM tokamak

    International Nuclear Information System (INIS)

    Azizov, Eh.A.; Buzhinskij, O.I.; Gladush, G.G.; Darmagraj, V.V.; Priyampol'skij, I.R.; Dvorkin, N.Ya.; Lejkin, I.N.; Tazhibaeva, I.L.; Shestakov, V.P.

    2001-01-01

    The constructing of the KTM tokamak is intended for wide scale studies of behavior both inner-chamber element materials and structures (first wall, limiters, divertor, hf-antennas, etc.) under conditions approaching to the ITER-FEAT and a future thermonuclear reactors. The KTM tokamak is designed for maintain of interaction conditions of plasma-wall, plasma flows and divertor field, stimulating conditions of ITER-FEAT; and for examination of a future tokamaks' materials. In the work the thermal loads on the first wall, divertor plates are presented

  13. Analysis and design of column reinforced masonry and concrete walls

    International Nuclear Information System (INIS)

    Doyle, J.M.; Roy, S.B.; Fang, S.J.

    1983-01-01

    Fundamental frequencies, maximum moments and maximum shear forces are determined as a function of the governing parameters, for several different boundary conditions. The quantities are obtained for uniform panels, for walls with openings typical of doorways and other penetrations, and for panels having a region of degraded stiffness. In addition to the internal forces and moment due to out-of-plane action, the stresses due to in-plane loading are also found. From the results curves are constructed which allow for easy computation of flexural frequency, and bending moments and shears due to dynamic loads normal to the wall. Furthermore, based on the studies of panels with geometric or material discontinuities, corrections to results for uniform panels are found which can be used if openings or weakened areas exist in the wall. Several conclusions are presented concerning effects on behavior due to varied column location, critical stiffness ratio for columns to be effective, and the effect of openings on overall behavior. A number of design recommendations are presented. While the motivation for the study came from the need to design masonry walls, the analysis results are applicable to solid concrete walls reinforced by vertical columns. (orig./HP)

  14. The Slogan Great Wall from the SDSS Data Release 4

    International Nuclear Information System (INIS)

    Deng Xin-Fa; He Ji-Zhou; Luo Cheng-Hong; Wu Ping; Tang Xiao-Xun; He Cong-Gen

    2007-01-01

    Using the MAIN galaxy data from the SDSS Data Release 4 (SDSS4), we further study the Sloan Great Wall by three-dimensional cluster analysis. Because the basic properties of Main galaxies change with redshift, we select 50942 Main galaxies having the same redshift region (0.07 ≤ z ≤ 0.09) as the Sloan Great Wall from the Main galaxy sample, and construct our SubMain sample. From the SubMain sample, 2013 isolated galaxies are identified at dimensionless radius r = 1.4. We perform the comparative studies of galaxy properties among the Sloan Great Wall, isolated galaxies and the SubMain sample in different redshift bins. It turns out that the statistical properties of luminosities and sizes of galaxies for the Sloan Great Wall, isolated galaxies and the SubMain sample are almost the same, the proportion of early-type isolated galaxies is relatively low. We also d that mean color of member galaxies of the Sloan Great Wall is redder than that of isolated galaxies. These results indicate that some properties of galaxies may be closely correlated with the environment or clustering. (author)

  15. Dynamic model based on voltage transfer curve for pattern formation in dielectric barrier glow discharge

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ben; He, Feng; Ouyang, Jiting, E-mail: jtouyang@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Duan, Xiaoxi [Research Center of Laser Fusion, CAEP, Mianyang 621900 (China)

    2015-12-15

    Simulation work is very important for understanding the formation of self-organized discharge patterns. Previous works have witnessed different models derived from other systems for simulation of discharge pattern, but most of these models are complicated and time-consuming. In this paper, we introduce a convenient phenomenological dynamic model based on the basic dynamic process of glow discharge and the voltage transfer curve (VTC) to study the dielectric barrier glow discharge (DBGD) pattern. VTC is an important characteristic of DBGD, which plots the change of wall voltage after a discharge as a function of the initial total gap voltage. In the modeling, the combined effect of the discharge conditions is included in VTC, and the activation-inhibition effect is expressed by a spatial interaction term. Besides, the model reduces the dimensionality of the system by just considering the integration effect of current flow. All these greatly facilitate the construction of this model. Numerical simulations turn out to be in good accordance with our previous fluid modeling and experimental result.

  16. Identifying barriers in the diffusion of renewable energy sources

    International Nuclear Information System (INIS)

    Eleftheriadis, Iordanis M.; Anagnostopoulou, Evgenia G.

    2015-01-01

    Rapid diffusion of renewable energy sources (RES) in the electricity power sector is crucial if the EU wants to fulfill its 2050 CO 2 reduction commitments. For this reason, identifying and alleviating all barriers that hinder the development of RES is necessary to the successful deployment of these technologies. This paper discusses the main barriers in the diffusion of wind and photovoltaic (PV) solar power in the Greek electricity sector by drawing on the literature of technological innovation systems and system functions. Furthermore, we provide an explanation of the different diffusion rates between the two technologies. Inadequate financial resources, low grid capacity, delays in the issuance of building permits, opposition from local communities to the construction of wind farms and the lack of a stable institutional framework are among the most important barriers that inhibit the diffusion of the wind and PV solar power. The nature of the barriers identified in this study calls for policy intervention. - Highlights: • Firms in the Greek wind and solar power sectors assess RES barriers. • Lack of financial resources is the most important RES barrier. • Lack of a stable institutional framework negatively affects RES deployment. • The support of the public sector is crucial to the diffusion of RES. •Wind power faces strong legitimization barriers

  17. Performance characteristics of a self-sealing/self-healing barrier

    International Nuclear Information System (INIS)

    McGregor, R.G.; Stegemann, J.A.

    1997-01-01

    Environment Canada and the Netherlands Energy Research Foundation are co-developers of a patented Self-Sealing/Self-Healing (SS/SH) Barrier system for containment of wastes which is licensed to Water Technology International Corporation. The SS/SH Barrier is intended for use as either a liner or cover for landfills, contaminated sites, secondary containment areas, etc., in the industrial, chemical, mining and municipal sectors, and also as a barrier to hydraulic flow for the transportation and construction industry. The SS/SH Barrier's most significant feature is its capability for self-repair in the event of a breach. By contrast, conventional barrier systems, such as clay, geomembrane, or geosynthetic clay liners can not be repaired without laborious excavation and reconstruction. Laboratory investigations have shown that the SS/SH Barrier concept will function with a variety of reactive materials. Self-Sealing/Self-Healing Barriers are cost competitive and consistently exhibit hydraulic conductivities ranging from 10 -9 to 10 -13 m/s, which decrease with time. These measurements meet or exceed the recommended hydraulic conductivity required by EPA for clay liners ( -9 m/s) used in landfills and hazardous waste sites. Results of mineralogical examination of the seal, diffusion testing, hydraulic conductivity measurement, and durability testing, including wet/dry, freeze/thaw cycling and leachate compatibility are also presented

  18. Measuring women's perceived ability to overcome barriers to healthcare seeking in Burkina Faso

    Directory of Open Access Journals (Sweden)

    Nikiema Béatrice

    2012-02-01

    Full Text Available Abstract Background In sub-Saharan Africa, women must overcome numerous barriers when they need modern healthcare. Respect of gender norms within the household and the community may still influence women's ability to obtain care. A lack of gender-sensitive instruments for measuring women's ability to overcome barriers compromises attempts to adequately quantify the burden and risk of exclusion they face when seeking modern healthcare. The aim of this study was to create and validate a synthetic measure of women's access to healthcare from a publicly available and possibly internationally comparable population-based survey. Method Seven questionnaire items from the Burkina Faso 2003 DHS were combined to create the index. Cronbach's alpha coefficient was used to test the reliability of the index. Exploratory factor analyses (EFA and confirmatory factor analyses (CFA were applied to evaluate the factorial structure and construct validity of the index while taking into account the hierarchical structure of the data. Results The index has a Cronbach's alpha of 0.75, suggesting adequate reliability. In EFA, three correlated factors fitted the data best. In CFA, the construct of perceived ability to overcome barriers to healthcare seeking emerged as a second-order latent variable with three domains: socioeconomic barriers, geographical barriers and psychosocial barriers. Model fit indices support the index's global validity for women of reproductive age in Burkina Faso. Evidence for construct validity comes from the finding that women's index scores increase with household living standard. Conclusion The DHS items can be combined into a reliable and valid, gender-sensitive index quantifying reproductive-age women's perceived ability to overcome barriers to healthcare seeking in Burkina Faso. The index complies conceptually with the sector-cross-cutting capability approach and enables measuring directly the perceived access to healthcare. Therefore it

  19. Ultimate shearing strength of aseismatic walls with many small holes for reactor buildings

    International Nuclear Information System (INIS)

    Yoshizaki, Seiji; Ezaki, Tetsuro; Korenaga, Takeyoshi; Sotomura, Kentaro.

    1984-01-01

    The aseismatic walls for reactor buildings have complicated forms, and are characterized by large wall thickness and high reinforcement ratio as compared with ordinary aseismatic walls. The forms are mainly box, cylinder or irregular polygonal prism and their combination. The design of the walls with many small holes has been performed on the basis of the reinforced concrete structure calculation standard of the Architectural Institute of Japan, following the case with large opening. When there are many small holes, the arrangement of reinforcement for the openings becomes complex, and the construction is difficult. It is necessary to rationalize the design and to simplify the reinforcement work. Under the background like this, the experiment to examine the shearing property in bending of the aseismatic walls with many small holes for reactor buildings was carried out, and horizontal loading test was performed on 43 specimens. The method of calculating the ultimate shearing strength of a wall without opening was proposed, and the method of applying it to a wall with many small holes is shown. The experimental method and the results, the examination of the experimental results, and the ultimate shearing strength of the aseismatic walls are reported. (Kako, I.)

  20. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    Heiser, J.; Dwyer, B.

    1995-01-01

    The primary objective of this project is to develop and demonstrate a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper will discuss the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration will take place at a cold site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington

  1. Information barriers

    International Nuclear Information System (INIS)

    Fuller, J.L.; Wolford, J.

    2001-01-01

    Full text: An information barrier (IB) consists of procedures and technology that prevent the release of sensitive information during a joint inspection of a sensitive nuclear item, and provides confidence that the measurement system into which it has been integrated functions exactly as designed and constructed. Work in the U.S. on radiation detection system information barriers dates back at least to 1990, even though the terminology is more recent. In January 1999 the Joint DoD-DOE Information Barrier Working Group was formed in the United States to help coordinate technical efforts related to information barrier R and D. This paper presents an overview of the efforts of this group, by its Chairs, as well as recommendations for further information barrier R and D. Progress on the demonstration of monitoring systems containing IBs is also provided. From the U.S. perspective, the basic, top-level functional requirements for the information barrier portion of an integrated radiation signature-information barrier inspection system are twofold: The host must be assured that his classified information is protected from disclosure to the inspecting party; and The inspecting party must be confident that the integrated inspection system measures, processes, and presents the radiation-signature-based measurement conclusion in an accurate and reproducible manner. It is the position of the United States that in the absence of any agreement to share classified nuclear weapons design information in the conduct of an inspection regime, the requirement to protect host country classified warhead design information is paramount and admits no tradeoff versus the confidence provided to the inspecting party in the accuracy and reproducibility of the measurements. The U.S. has reached an internal consensus on several critical design elements that define a general standard for radiation signature information barrier design. These criteria have stood the test of time under intense

  2. Barriers to Zero Energy Construction (ZEC); technically possible; why not succeed yet?

    NARCIS (Netherlands)

    Abdalla, G.; Maas, G.J.; Demers, C.M.H.; Potvin, A

    2009-01-01

    The construction activities have a significant impact on the environment in terms of energy consumption and use of raw materials. The construction industry has been challenged to meet the human needs in environmentally friendly ways. Environmentally friendly measures and proven renewable energy

  3. Recent Advances in Gas Barrier Thin Films via Layer-by-Layer Assembly of Polymers and Platelets.

    Science.gov (United States)

    Priolo, Morgan A; Holder, Kevin M; Guin, Tyler; Grunlan, Jaime C

    2015-05-01

    Layer-by-layer (LbL) assembly has emerged as the leading non-vacuum technology for the fabrication of transparent, super gas barrier films. The super gas barrier performance of LbL deposited films has been demonstrated in numerous studies, with a variety of polyelectrolytes, to rival that of metal and metal oxide-based barrier films. This Feature Article is a mini-review of LbL-based multilayer thin films with a 'nanobrick wall' microstructure comprising polymeric mortar and nano-platelet bricks that impart high gas barrier to otherwise permeable polymer substrates. These transparent, water-based thin films exhibit oxygen transmission rates below 5 × 10(-3) cm(3) m(-2) day(-1) atm(-1) and lower permeability than any other barrier material reported. In an effort to put this technology in the proper context, incumbent technologies such as metallized plastics, metal oxides, and flake-filled polymers are briefly reviewed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Characteristics of wall pressure over wall with permeable coating

    Energy Technology Data Exchange (ETDEWEB)

    Song, Woo Seog; Shin, Seungyeol; Lee, Seungbae [Inha Univ., Incheon (Korea, Republic of)

    2012-11-15

    Fluctuating wall pressures were measured using an array of 16 piezoelectric transducers beneath a turbulent boundary layer. The coating used in this experiment was an open cell, urethane type foam with a porosity of approximately 50 ppi. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The boundary layer on the flat plate was measured by using a hot wire probe, and the CPM method was used to determine the skin friction coefficient. The wall pressure autospectra and streamwise wavenumber frequency spectra were compared to assess the attenuation of the wall pressure field by the coating. The coating is shown to attenuate the convective wall pressure energy. However, the relatively rough surface of the coating in this investigation resulted in a higher mean wall shear stress, thicker boundary layer, and higher low frequency wall pressure spectral levels compared to a smooth wall.

  5. Nonlinear analysis of composite thin-walled helicopter blades

    Science.gov (United States)

    Kalfon, J. P.; Rand, O.

    Nonlinear theoretical modeling of laminated thin-walled composite helicopter rotor blades is presented. The derivation is based on nonlinear geometry with a detailed treatment of the body loads in the axial direction which are induced by the rotation. While the in-plane warping is neglected, a three-dimensional generic out-of-plane warping distribution is included. The formulation may also handle varying thicknesses and mass distribution along the cross-sectional walls. The problem is solved by successive iterations in which a system of equations is constructed and solved for each cross-section. In this method, the differential equations in the spanwise directions are formulated and solved using a finite-differences scheme which allows simple adaptation of the spanwise discretization mesh during iterations.

  6. Waste Isolation Pilot Plant: Alcove Gas Barrier trade-off study

    International Nuclear Information System (INIS)

    Lin, M.S.; Van Sambeek, L.L.

    1992-07-01

    A modified Kepner-Tregoe method was used for a trade-off study of Alcove Gas Barrier (AGB) concepts for the Waste Isolation Pilot Plant. The AGB is a gas-constraining seal to be constructed in an alcove entrance drift. In this trade-off study, evaluation criteria were first selected. Then these criteria were classified as to their importance to the task, assigning a weighting value to each aspect. Eleven conceptual design alternatives were developed based on geometrical/geological considerations, construction materials, constructibility, and other relevant factors and evaluated

  7. Association Mapping of Cell Wall Synthesis Regulatory Genes and Cell Wall Quality in Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Bartley, Laura [Univ. of Oklahoma, Norman, OK (United States). Dept. of Microbiology and Plant Biology; Wu, Y. [Oklahoma State Univ., Stillwater, OK (United States); Zhu, L. [Oklahoma State Univ., Stillwater, OK (United States); Brummer, E. C. [Noble Foundation, Ardmore, OK (United States); Saha, M. [Noble Foundation, Ardmore, OK (United States)

    2016-05-31

    Inefficient conversion of biomass to biofuels is one of the main barriers for biofuel production from such materials. Approximately half of polysaccharides in biomass remain unused by typical biochemical conversion methods. Conversion efficiency is influenced by the composition and structure of cell walls of biomass. Grasses such as wheat, maize, and rice, as well as dedicated perennial bioenergy crops, like switchgrass, make up ~55% of biomass that can be produced in the United States. Grass cell walls have a different composition and patterning compared with dicotyledonous plants, including the well-studied model plant, Arabidopsis. This project identified genetic determinants of cell wall composition in grasses using both naturally occurring genetic variation of switchgrass and gene network reconstruction and functional assays in rice. In addition, the project linked functional data in rice and other species to switchgrass improvement efforts through curation of the most abundant class of regulators in the switchgrass genome. Characterizing natural diversity of switchgrass for variation in cell wall composition and properties, also known as quality, provides an unbiased avenue for identifying biologically viable diversity in switchgrass cell walls. To characterizing natural diversity, this project generated cell wall composition and enzymatic deconstruction data for ~450 genotypes of the Switchgrass Southern Association Collection (SSAC), a diverse collection composed of 36 switchgrass accessions from the southern U.S. distribution of switchgrass. Comparing these data with other measures of cell wall quality for the same samples demonstrated the complementary nature of the diverse characterization platforms now being used for biomass characterization. Association of the composition data with ~3.2K single nucleotide variant markers identified six significant single nucleotide variant markers co-associated with digestibility and another compositional trait. These

  8. Biointrusion test plan for the Permanent Isolation Surface Barrier Prototype

    International Nuclear Information System (INIS)

    Link, S.O.; Cadwell, L.L.; Brandt, C.A.; Downs, J.L.; Rossi, R.E.; Gee, G.W.

    1994-04-01

    This document provides a testing and monitoring plan for the biological component of the prototype barrier slated for construction at the Hanford Site. The prototype barrier is an aboveground structure engineered to demonstrate the basic features of an earthen cover system. It is designed to permanently isolate waste from the biosphere. The features of the barrier include multiple layers of soil and rock materials and a low-permeability asphalt sublayer. The surface of the barrier consists of silt loam soil, covered with plants. The barrier sides are reinforced with rock or coarse earthen-fill to protect against wind and water erosion. The sublayers inhibit plant and animal intrusion and percolation of water. A series of tests will be conducted on the prototype barrier over the next several years to evaluate barrier performance under extreme climatic conditions. Plants and animals will play a significant role in the hydrologic and water and wind erosion characteristics of the prototype barrier. Studies on the biological component of the prototype barrier will include work on the initial revegetation of the surface, continued monitoring of the developing plant community, rooting depth and dispersion in the context of biointrusion potential, the role of plants in the hydrology of the surface and toe regions of the barrier, the role of plants in stabilizing the surface against water and wind erosion, and the role of burrowing animals in the hydrology and water and wind erosion of the barrier

  9. Dynamic Fungal Cell Wall Architecture in Stress Adaptation and Immune Evasion.

    Science.gov (United States)

    Hopke, Alex; Brown, Alistair J P; Hall, Rebecca A; Wheeler, Robert T

    2018-04-01

    Deadly infections from opportunistic fungi have risen in frequency, largely because of the at-risk immunocompromised population created by advances in modern medicine and the HIV/AIDS pandemic. This review focuses on dynamics of the fungal polysaccharide cell wall, which plays an outsized role in fungal pathogenesis and therapy because it acts as both an environmental barrier and as the major interface with the host immune system. Human fungal pathogens use architectural strategies to mask epitopes from the host and prevent immune surveillance, and recent work elucidates how biotic and abiotic stresses present during infection can either block or enhance masking. The signaling components implicated in regulating fungal immune recognition can teach us how cell wall dynamics are controlled, and represent potential targets for interventions designed to boost or dampen immunity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Effect of cladding systems on moisture performance of wood-framed walls in a mixed-humid climate

    Science.gov (United States)

    S. Craig Drumheller; Charles G. Carll

    2010-01-01

    A 22-month field investigation of nine different north-and south-oriented wood-framed wall assemblies was conducted to determine the moisture performance of various wall construction types, most of which incorporated absorptive cladding. The study was conducted on the campus of the National Association of Home Builders (NAHB) Research Center, in Upper Marlboro, MD, 20...

  11. Investigation of the performance of cement-bentonite cut-off walls in aggressive ground at a disused gasworks site

    International Nuclear Information System (INIS)

    Tedd, P.; Holton, I.R.; Butcher, A.P.; Wallace, S.

    1997-01-01

    There has been an increased use of cement-bentonite slurry trench cut-off walls to control the lateral migration of pollution in the UK. Concerns inevitably exist about their performance in chemically aggressive ground particularly in the long term. To address some of the uncertainties a programme of field and laboratory research is being undertaken at a disused gasworks in the UK. Elevated levels of sulphate and other contaminants are present on the site and could potentially change the properties of the cement-bentonite. Two boxes, 10m square in plan, by 5m deep have been constructed, one with and one without an HDPE membrane, to isolate parts of the site. Local hydraulic gradients across the walls have been created by pumping from within the boxes. Isolated lengths of wall have been constructed which are being used to assess and develop in-situ testing techniques such as the piezocone for measuring permeability, strength and overall integrity of the wall

  12. Reinforced soil structures. Volume I, Design and construction guidelines

    Science.gov (United States)

    1990-11-01

    This report presents comprehensive guidelines for evaluating and using soil reinforcement techniques in the construction of retaining walls, embankment slopes, and natural or cut slopes. A variety of available systems for reinforced soil including in...

  13. Enhanced probabilistic decision analysis for radiological confinement barriers of the International Thermonuclear Experimental Reactor

    International Nuclear Information System (INIS)

    Golinescu, R.P.; Kazimi, M.S.

    1998-01-01

    To ensure a defence-in-depth approach, several radiological confinement barriers surrounding a tokamak plant can be employed. A methodology using probabilistic risk assessment (PRA) techniques is a useful tool for evaluating the performance of each confinement barrier within the context of a limited allowable risk of accidental radioactivity releases. Such a methodology was developed and applied to the confinement strategy for the International Thermonuclear Experimental Reactor (ITER). Accident sequence models were constructed for each of the confinement barriers to evaluate the probabilities of events leading to radioactive releases from the corresponding confinement barrier. The current ITER design requirements set radioactive release and dose limits for individual event sequences grouped in categories by frequency. To limit the plant's overall risk and account for event uncertainties in both frequency and consequence, an analytical form for a limit line is derived here as a complementary cumulative frequency (CCF) of radioactive releases to the environment. By comparing the releases from each confinement barrier against the limit line, a decision can be made about the number of barriers required to comply with the design requirements. The first barrier is the vacuum vessel (VV) and the primary heat transfer systems. The second confinement barrier consists of the cryostat vessel (CV) and the heat transfer system vaults. In case the outer building is needed to act as a third barrier for ITER, a decision model using the multi-attribute utility theory was constructed to help the designer choose the best type of tokamak building. The decision model allows for performing sensitivity analysis on relevant parameters and for design features of new options for the ITER tokamak building. (orig.)

  14. Reinforcement mechanism of multi-anchor wall with double wall facing

    Science.gov (United States)

    Suzuki, Kouta; Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo

    2017-10-01

    The reinforced soil wall has high seismic performance as generally known. However, the seismic behavior has not been clarified accurately yet, especially on multi-anchor wall with double wall facing. Indefinite behavior of reinforced soil wall during earthquake make us complicated in case with adopting to the abutment, because of arrangement of anchor plate as reinforcement often different according to the width of roads. In this study, a series of centrifuge model tests were carried out to investigate the reinforcement mechanism of multi anchor wall with double wall facing from the perspective of the vertical earth pressure. Several types of reinforce arrangement and rigid wall were applied in order to verify the arch function in the reinforced regions. The test results show unique behavior of vertical earth pressure, which was affected by arch action. All the vertical earth pressure placed behind facing panel, are larger than that of middle part between facing panel despite of friction between backfill and facing panel. Similar results were obtained in case using rigid wall. On the other hands, the vertical earth pressure, which were measured at the 3cm high from bottom of model container, shows larger than that of bottom. This results show the existence of arch action between double walls. In addition, it implies that the wall facing of such soil structure confined the backfill as pseudo wall, which is very reason that the multi anchor wall with double wall facing has high seismic performance.

  15. Use of Natural-Fiber Bio-Composites in Construction versus Traditional Solutions: Operational and Embodied Energy Assessment.

    Science.gov (United States)

    Galan-Marin, Carmen; Rivera-Gomez, Carlos; Garcia-Martinez, Antonio

    2016-06-13

    During the last decades natural polymers have become more and more frequent to replace traditional inorganic stabilizers in building materials. The purpose of this research is to establish a comparison between the most conventional building material solutions for load-bearing walls and a type of biomaterial. This comparison will focus on load-bearing walls as used in a widespread type of twentieth century dwelling construction in Europe and still used in developing countries nowadays. To carry out this analysis, the structural and thermal insulation characteristics of different construction solutions are balanced. The tool used for this evaluation is the life cycle assessment throughout the whole lifespan of these buildings. This research aims to examine the environmental performance of each material assessed: fired clay brick masonry walls (BW), concrete block masonry walls (CW), and stabilized soil block masonry walls (SW) stabilized with natural fibers and alginates. These conventional and new materials are evaluated from the point of view of both operational and embodied energy.

  16. Discrete quark-lepton symmetry need not pose a cosmological domain wall problem

    International Nuclear Information System (INIS)

    Lew, H.; Volkas, R.R.

    1992-01-01

    Quarks and leptons may be related to each other through a spontaneously broken discrete symmetry. Models with acceptable and interesting collider phenomenology have been constructed which incorporate this idea. However, the standard Hot Big Bang model of cosmology is generally considered to eschew spontaneously broken discrete symmetries because they often lead to the formation of unacceptably massive domain walls. It is pointed out that there are a number of plausible quark-lepton symmetric models in nature which do not produce cosmologically troublesome domain walls. 30 refs

  17. Limitation of radioactive excursions by the containment construction

    International Nuclear Information System (INIS)

    Janssen, L.G.J.

    1987-01-01

    The last barrier against the spread of fission products into the environment consists, in nuclear power plants, of the containment construction or safety enclosure. A brief survey of the influence of such an enclosure on the safety of a nuclear power plant is outlined for the various containment constructions for light-water reactors. Also the possibilities of failure of these constructions are discussed and some processes are described which can contribute effectively on the quantity of fission products that can be spread into the environment in case of a reactor accident. (Auth.)

  18. Sasol Coal`s `better brick` for colliery ventilation walls

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-01

    Sasol coal has developed a better brick for construction of ventilation walls underground. It has proven to be a speedy and cost-saving alternative to the standard concrete block used for the purpose. The brick has an interlocking design ensuring that it is laid correctly. Unlike the conventional concrete block, the ventilation walls built for the new brick do not have to be plastered to achieve airtightness. The skills required to build such walls are minimal as the design of the brick makes it virtually impossible to lay it badly or unevenly - further facilitated by the absence of mortar. While introducing the new method Sasol Coal took the opportunity to introduce a purpose-made trailer for transporting the bricks, with the trailer doubling as a building platform on site. This has further contributed to the efficiency and speed of the operation. It has also reduced to a minimum the number of times the bricks are handled, thus cutting down on breakages. 1 fig.

  19. Decreased Charge Transport Barrier and Recombination of Organic Solar Cells by Constructing Interfacial Nanojunction with Annealing-Free ZnO and Al Layers.

    Science.gov (United States)

    Liu, Chunyu; Zhang, Dezhong; Li, Zhiqi; Zhang, Xinyuan; Guo, Wenbin; Zhang, Liu; Ruan, Shengping; Long, Yongbing

    2017-07-05

    To overcome drawbacks of the electron transport layer, such as complex surface defects and unmatched energy levels, we successfully employed a smart semiconductor-metal interfacial nanojunciton in organic solar cells by evaporating an ultrathin Al interlayer onto annealing-free ZnO electron transport layer, resulting in a high fill factor of 73.68% and power conversion efficiency of 9.81%. The construction of ZnO-Al nanojunction could effectively fill the surface defects of ZnO and reduce its work function because of the electron transfer from Al to ZnO by Fermi level equilibrium. The filling of surface defects decreased the interfacial carrier recombination in midgap trap states. The reduced surface work function of ZnO-Al remodulated the interfacial characteristics between ZnO and [6,6]-phenyl C71-butyric acid methyl ester (PC 71 BM), decreasing or even eliminating the interfacial barrier against the electron transport, which is beneficial to improve the electron extraction capacity. The filled surface defects and reduced interfacial barrier were realistically observed by photoluminescence measurements of ZnO film and the performance of electron injection devices, respectively. This work provides a simple and effective method to simultaneously solve the problems of surface defects and unmatched energy level for the annealing-free ZnO or other metal oxide semiconductors, paving a way for the future popularization in photovoltaic devices.

  20. A model to predict radon exhalation from walls to indoor air based on the exhalation from building material samples

    International Nuclear Information System (INIS)

    Sahoo, B.K.; Sapra, B.K.; Gaware, J.J.; Kanse, S.D.; Mayya, Y.S.

    2011-01-01

    In recognition of the fact that building materials are an important source of indoor radon, second only to soil, surface radon exhalation fluxes have been extensively measured from the samples of these materials. Based on this flux data, several researchers have attempted to predict the inhalation dose attributable to radon emitted from walls and ceilings made up of these materials. However, an important aspect not considered in this methodology is the enhancement of the radon flux from the wall or the ceiling constructed using the same building material. This enhancement occurs mainly because of the change in the radon diffusion process from the former to the latter configuration. To predict the true radon flux from the wall based on the flux data of building material samples, we now propose a semi-empirical model involving radon diffusion length and the physical dimensions of the samples as well as wall thickness as other input parameters. This model has been established by statistically fitting the ratio of the solution to radon diffusion equations for the cases of three-dimensional cuboidal shaped building materials (such as brick, concrete block) and one dimensional wall system to a simple mathematical function. The model predictions have been validated against the measurements made at a new construction site. This model provides an alternative tool (substitute to conventional 1-D model) to estimate radon flux from a wall without relying on 226 Ra content, radon emanation factor and bulk density of the samples. Moreover, it may be very useful in the context of developing building codes for radon regulation in new buildings. - Research highlights: → A model is proposed to predict radon flux from wall using flux of building material. → It is established based on the diffusion mechanism in building material and wall. → Study showed a large difference in radon flux from building material and wall. → Model has been validated against the measurements made at