WorldWideScience

Sample records for liner shipping hub

  1. Liner Shipping Hub Network Design in a Competitive Environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    A new mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses competition between a newcomer liner service provider and an alliance, both operating on hub-and-spoke networks. The newcomer company maximizes its market share...

  2. Liner shipping hub network design in a competitive environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    2010-01-01

    A mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses the competition between a newcomer liner service provider and an existing dominating operator, both operating on hub-and-spoke networks. The newcomer company maximizes its...

  3. Liner shipping hub network design in a competitive environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    2010-01-01

    A mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses the competition between a newcomer liner service provider and an existing dominating operator, both operating on hub-and-spoke networks. The newcomer company maximizes i...

  4. Fleet deployment, network design and hub location of liner shipping companies

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Pisinger, David

    2011-01-01

    A mixed integer linear programming formulation is proposed for the simultaneous design of network and fleet deployment of a deep-sea liner service provider. The underlying network design problem is based on a 4-index (5-index by considering capacity type) formulation of the hub location problem...

  5. Fleet deployment, network design and hub location of liner shipping companies

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Pisinger, David

    2011-01-01

    A mixed integer linear programming formulation is proposed for the simultaneous design of network and fleet deployment of a deep-sea liner service provider. The underlying network design problem is based on a 4-index (5-index by considering capacity type) formulation of the hub location problem...

  6. Optimization in liner shipping

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    2017-01-01

    Seaborne trade is the lynchpin in almost every international supply chain, and about 90% of non-bulk cargo worldwide is transported by container. In this survey we give an overview of data-driven optimization problems in liner shipping. Research in liner shipping is motivated by a need for handling...... research....

  7. Liner Shipping Fleet Repositioning

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller

    2011-01-01

    , can be accurately modeled. Numerous liner shipping fleet repositioning problems are solved each year by the world’s shipping firms without the assistance of any decision support, even though humans can require between two to three days to find a reasonable solution. Finding optimal repositionings...... to complex handling and timing restrictions. The objective of the problem is cost minimization, which translates nearly directly into the minimization of CO2 emissions and pollution. Additionally, it is important that all cost elements, including the ones that are only loosely coupled with activity choices...

  8. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Pisinger, David

    2017-01-01

    We present a solution method for the liner shipping network design problem which is a core strategic planning problem faced by container carriers. We propose the first practical algorithm which explicitly handles transshipment time limits for all demands. Individual sailing speeds at each service...... are presented showing very promising results for realistic global liner shipping networks. Due to a number of algorithmic enhancements, the obtained solutions can be found within the same time frame as used by previous algorithms not handling time constraints. Furthermore, we present a sensitivity analysis...

  9. Automated Planning for Liner Shipping Fleet Repositioning

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller; Kroer, Christian

    2012-01-01

    The Liner Shipping Fleet Repositioning Problem (LSFRP) poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. The LSFRP is characterized by chains of interacting activities, many of which have costs...

  10. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad

    The goal of this thesis is to develop decision support tools, which can be used to optimize container shipping networks while supporting competitive transportation services. The competitiveness of container liner shipping is to a high degree determined by transportation times and number of transs......The goal of this thesis is to develop decision support tools, which can be used to optimize container shipping networks while supporting competitive transportation services. The competitiveness of container liner shipping is to a high degree determined by transportation times and number...... shipping company earnings.The operation of the route net constitute the majority of the total costs, so it is essential to achieve a good capacity utilization in a route plan with travel times that satisfy customer requirements. Most academic articles dealing with the design of container networks neither.......The contributions of this thesis cover modeling, methodology, and applications.The developed methods address operational (cargo routing), tactical (speed optimization and service selection), and strategic (network design) planning problems faced by liner shipping companies. Ultimately, the proposed methods help...

  11. Single liner shipping service design

    DEFF Research Database (Denmark)

    Plum, Christian Edinger Munk; Pisinger, David; Salazar-González, Juan-José

    2014-01-01

    demand under commercially driven constraints. This paper introduces the Single Liner Shipping Service Design Problem. Arc-flow and path-flow models are presented using state-of-the-art elements from the wide literature on pickup and delivery problems. A Branch-and-Cut-and-Price algorithm is proposed...

  12. Simultaneous Fleet Deployment and Network Design of Liner Shipping

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Pisinger, David

    A mixed integer linear programming formulation is proposed for the simultaneous design of network and fleet deployment of a liner service providers for deep-sea shipping. The underlying network design problem is based on a 4-index (5-index by considering capacity type) formulation of the hub...

  13. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Pisinger, David

    We present a solution method for the liner shipping network design problem which is a core strategic planning problem faced by container carriers. We propose the first practical algorithm which explicitly handles transshipment time limits for all demands. Individual sailing speeds at each service...... leg are used to balance sailings speed against operational costs, hence ensuring that the found network is competitive on both transit time and cost. We present a matheuristic for the problem where a MIP is used to select which ports should be inserted or removed on a route. Computational results...... are presented showing very promising results for realistic global liner shipping networks. Due to a number of algorithmic enhancements, the obtained solutions can be found within the same time frame as used by previous algorithms not handling time constraints. Furthermore we present a sensitivity analysis...

  14. Automated Planning for Liner Shipping Fleet Repositioning

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller; Kroer, Christian

    2012-01-01

    The Liner Shipping Fleet Repositioning Problem (LSFRP) poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. The LSFRP is characterized by chains of interacting activities, many of which have costs that are a ......The Liner Shipping Fleet Repositioning Problem (LSFRP) poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. The LSFRP is characterized by chains of interacting activities, many of which have costs......-integer program (MIP) and a novel method called Temporal Optimization Planning (TOP). We evaluate the performance of each of these techniques on a dataset of real-world instances from our industrial collaborator, and show that automated planning scales to the size of problems faced by industry....

  15. Classification of Ship Routing and Scheduling Problems in Liner Shipping

    DEFF Research Database (Denmark)

    Kjeldsen, Karina Hjortshøj

    2011-01-01

    This article provides a classification scheme for ship routing and scheduling problems in liner shipping in line with the current and future operational conditions of the liner shipping industry. Based on the classification, the literature is divided into groups whose main characteristics...

  16. Designing Indonesian Liner Shipping Network

    Directory of Open Access Journals (Sweden)

    Armand Omar Moeis

    2017-06-01

    Full Text Available As the largest archipelago nation in the world, Indonesia’s logistics system has not shown excellence according to the parameters of logistics performance index and based on logistics costs percentages from overall GDP. This is due to the imbalances of trading on the western and eastern regions in Indonesia, which impacts the transportation systems costs to and from the eastern regions. Therefore, it is imperative to improve the competitiveness of Indonesian maritime logistics through maritime logistics network design. This research will focus on three levels of decision making in logistics network design, which include type of ships in the strategic level, shipping routes in the tactical level, and container allocation in the operational level with implementing butterfly routes in Indonesia’s logistics networking problems. Furthermore, this research will analyze the impact of Pendulum Nusantara and Sea Toll routes against the company profits and percentages of containers shipped. This research will also foresee how demand uncertainties and multi-period planning should affect decision making in designing the Indonesian Liner Shipping Network.

  17. The Liner Shipping Fleet Repositioning Problem with Cargo Flows

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller

    2012-01-01

    We solve an important problem for the liner shipping industry called the Liner Shipping Fleet Repositioning Problem (LSFRP). The LSFRP poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. Shippers wish...

  18. Time constrained liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Desaulniers, Guy

    2016-01-01

    We present a mathematical model and a solution method for the liner shipping network design problem. The model takes into account coordination between vessels and transit time restrictions on the cargo flow. The solution method is an improvement heuristic, where an integer program is solved...... iteratively to perform moves in a large neighborhood search. Our improvement heuristic is applicable as a real-time decision support tool for a liner shipping company. It can be used to find improvements to the network when evaluating changes in operating conditions or testing different scenarios....... Computational results on the benchmark suite LINER-LIB are reported....

  19. The Liner Shipping Fleet Repositioning Problem with Cargo Flows

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller

    2012-01-01

    We solve an important problem for the liner shipping industry called the Liner Shipping Fleet Repositioning Problem (LSFRP). The LSFRP poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. Shippers wish...... in the literature. We introduce a novel mathematical model of the LSFRP with cargo flows based on a carefully constructed graph and evaluate it on real world data from our industrial collaborator....

  20. Solving the Liner Shipping Fleet Repositioning Problem with Cargo Flows

    DEFF Research Database (Denmark)

    Tierney, Kevin; Askelsdottir, Björg; Jensen, Rune Møller

    2015-01-01

    We solve a central problem in the liner shipping industry called the liner shipping fleet repositioning problem (LSFRP). The LSFRP poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between routes in a liner shipping network. Liner carriers wish...... introduce a novel mathematical model and a simulated annealing algorithm for the LSFRP with cargo flows that makes use of a carefully constructed graph; we evaluate these approaches using real-world data from our industrial collaborator. Additionally, we compare the performance of our approach against...

  1. Routing and scheduling and fleet management for liner shipping

    DEFF Research Database (Denmark)

    Kjeldsen, Karina Hjortshøj

    2009-01-01

    The problem of routing, scheduling and fleet management in global liner shipping is presented. The developed model incorporates the ships' speed as a decision variable. Furthermore, the model must be able to handle problems of the size and complexity experienced by the global liner shipping...

  2. A PDDL Domain for the Liner Shipping Fleet Repositioning Problem

    DEFF Research Database (Denmark)

    Tierney, Kevin; Coles, Amanda; Coles, Andrew

    The Liner Shipping Fleet Repositioning Problem (LSFRP) poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. The LSFRP is characterized by chains of interacting activities, many of which have costs that are a ......The Liner Shipping Fleet Repositioning Problem (LSFRP) poses a large financial burden on liner shipping firms. During repositioning, vessels are moved between services in a liner shipping network. The LSFRP is characterized by chains of interacting activities, many of which have costs...... that are a function of their duration; for example, sailing slowly between two ports is cheaper than sailing quickly. Despite its great industrial importance, the LSFRP has received little attention in the literature. We model the LSFRP using PDDL and solve it using the planner....

  3. Speed Optimization in Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    In the Liner Shipping Network Design Problem (LSNDP) services sail at a given speed throughout a round trip. In reality most services operate with a speed differentiated head- and back-haul, or even individual speeds on every sailing between two ports. The speed of a service is decisive...... for the bunker consumption in the network as well as the transit time of cargo. Speed optimization has been considered for tramp shipping showing significant reductions in fuel consumption. However, variable speeds has not been considered for post optimization of the LSNDP, where speed optimization could result...... in changes to the cargo flow due to transit time restrictions as well as significant savings in fuel consumption and required vessel deployment due to a weekly frequency requirement. We present a heuristic method to calculate variable speed on a service and present computational results for improving...

  4. Classification of routing and scheduling problems in liner shipping

    DEFF Research Database (Denmark)

    Hjortshøj Kjeldsen, Karina

    A classification scheme for routing and scheduling problems in liner shipping is developed and subsequently used to classify existing literature on the subject. Based on the classification the articles are grouped, and the main characteristics of each group and article are described. The grouping...... may serve as a catalyst towards developing a model or a group of models that covers the main problems within routing and scheduling in liner shipping....

  5. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Pisinger, David

    We present a matheuristic, an integer programming based heuristic, for the liner shipping network design problem. This problem consists of finding a set of container shipping routes defining a capacitated network for cargo transport. The objective is to maximize the revenue of cargo transport......, while minimizing the cost of operating the network. Liner shipping companies publish a set of routes with a time schedule, and it is an industry standard to have a weekly departure at each port call on a route. A weekly frequency is achieved by deploying several vessels to a single route, respecting...

  6. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy

    2012-01-01

    We present a matheuristic, an integer programming based heuristic, for the Liner Shipping Network Design Problem. The heuristic applies a greedy construction heuristic based on an interpretation of the liner shipping network design problem as a multiple quadratic knapsack problem. The construction...... for revenue and transshipment of cargo along with in/decrease of vessel- and operational cost for the current solution. The evaluation functions may be used by heuristics in general to evaluate changes to a network design without solving a large scale multicommodity flow problem....... heuristic is combined with an improvement heuristic with a neighborhood defined by the solution space of a mixed integer program. The mixed integer program optimizes the removal and insertion of several port calls on a liner shipping service. The objective function is based on evaluation functions...

  7. Synergistic Integration of Liner Shipping and Economic Development

    Directory of Open Access Journals (Sweden)

    Edvard Roškar

    2008-07-01

    Full Text Available Liner shipping with all its specific features plays an importantrole in the economic development of a country whose portsare involved. In the strategic goals of maritime policy for the period2005-2009 the European Commission stresses the needfor a sustainable environmental development and economicgrowth. Besides, it points out the necessity for the fulfilment ofall maritime potentials. Yet, individual EU member states frequentlycreate the environment, which discourages the developmentof their own national maritime economy. Unfortunately,this applies also to the Republic of Slovenia. The current paperoffers a detailed analysis of the weaknesses and benefits of theclassical liner shipping in present day.

  8. Optimizing Liner Shipping Fleet Repositioning Plans

    DEFF Research Database (Denmark)

    Tierney, Kevin

    With the incredible growth of containerization over the past half century, shipping lines and ports are facing increasing challenges in ensuring that containers arrive at their destinations on time and on budget. This dissertation addresses several critical problems to the operations of shipping...

  9. Liner Shipping Service Scheduling with Workshift Costs

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander

    Container shipping companies are currently facing combined challenges of overcapacity and volatile fuel prices. In addition, rising concerns about greenhouse gas emissions has made it crucial for shipping companies to reduce their fuel consumption. The consumption of fuel for shipping vessel...... while ensuring that given transit time limits for the carried cargo is satisfied, and considering the layover time for containers transshipping between services. Workshift times and cost are included ensuring that changing the port visit time will not introduce an addition cost for the port operations...

  10. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Pisinger, David

    2014-01-01

    We present an integer programming based heuristic, a matheuristic, for the liner shipping network design problem. This problem consists of finding a set of container shipping routes defining a capacitated network for cargo transport. The objective is to maximize the revenue of cargo transport....... The matheuristic can also be applied as a decision support tool to improve an existing network by optimizing on a designated subset of the routes. A case study is presented for this approach with very promising results. © 2014 Elsevier Ltd. All rights reserved......., while minimizing the cost of operating the network. Liner shipping companies publish a set of routes with a time schedule, and it is an industry standard to have a weekly departure at each port call on a route. A weekly frequency is achieved by deploying several vessels to a single route, respecting...

  11. Logistics service sharing in supply hub in industrial park (SHIP)

    OpenAIRE

    Qiu, Xuan; 邱璇

    2013-01-01

    Industrial parks have played an indispensible role in boosting economic and industrial development. However, further development has been impeded by the shortage of land resources and by duplicate investments on common physical assets and services. This thesis proposes the concept of Supply Hub in Industrial Park (SHIP) as a public provider of warehousing and transportation services shared by manufacturing enterprises located within an industrial park. This research investigates four typic...

  12. Integrated cargo routing and ship scheduling in liner shipping

    DEFF Research Database (Denmark)

    Kjeldsen, Karina Hjortshøj

    The problem consists of creating routes and schedules for a heterogeneous fleet of ships while determining the cargo routing and the speed for all relevant port pair/ship combinations. Transshipment is allowed in ports with transshipment capabilities. The service frequency is fixed at one week....... Since the speed of the ships is a decision variable, the developed model is nonlinear. The model is made linear by means of variable redefinition. Using decomposition the linearized model is split into a master problem and a sub problem per ship, and solved by a column generation algorithm....

  13. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Pisinger, David

    We present a matheuristic, an integer programming based heuristic, for the liner shipping network design problem. This problem consists of finding a set of container shipping routes defining a capacitated network for cargo transport. The objective is to maximize the revenue of cargo transport...... the available fleet of container vessels. The cargo transports make extensive use of transshipments between routes and the number of transshipments of the cargo flow is decisive for network profitability. Computational results are reported for the benchmark suite LINER-LIB 2012 following the industry standard...... of weekly departures on every schedule. The heuristic shows overall good performance and is able to find high quality solutions within competitive execution times. The matheuristic can also be applied as a decision support tool to improve an existing network by optimizing on a designated subset...

  14. Integrated cargo routing and ship scheduling in liner shipping

    DEFF Research Database (Denmark)

    Kjeldsen, Karina Hjortshøj

    The problem consists of creating routes and schedules for a heterogeneous fleet of ships while determining the cargo routing and the speed for all relevant port pair/ship combinations. Transshipment is allowed in ports with transshipment capabilities. The service frequency is fixed at one week...

  15. A Base Integer Programming Model and Benchmark Suite for Liner-Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Alvarez, Fernando; Plum, Christian Edinger Munk

    2014-01-01

    sources of liner shipping for OR researchers in general. We describe and analyze the liner-shipping domain applied to network design and present a rich integer programming model based on services that constitute the fixed schedule of a liner shipping company. We prove the liner-shipping network design...... problem to be strongly NP-hard. A benchmark suite of data instances to reflect the business structure of a global liner shipping network is presented. The design of the benchmark suite is discussed in relation to industry standards, business rules, and mathematical programming. The data are based on real......The liner-shipping network design problem is to create a set of nonsimple cyclic sailing routes for a designated fleet of container vessels that jointly transports multiple commodities. The objective is to maximize the revenue of cargo transport while minimizing the costs of operation...

  16. Liner Shipping Fleet Deployment with Sustainable Collaborative Transportation

    Directory of Open Access Journals (Sweden)

    Gang Du

    2016-02-01

    Full Text Available Facing sharp competition in the market for shipping companies, it is necessary to make reasonable and efficient decisions to optimize the container shipping line network so as to improve the shipping efficiency and reduce the transportation cost, as well as to realize the transportation sustainability. Therefore, the liner ship fleet deployment problem with collaborative transportation is proposed in this paper. This problem is formulated as a mixed-integer linear programming model that takes collaborative transportation into consideration. The model includes fixed cost, variable cost, berth cost, transport cost, penalty, compensation cost, and so on. To achieve the sustainable development of collaborative transportation, the shipping companies could make a selection between the internal routes and the external routes to serve each task by comparing the distance between the above routes. A real Asia-Europe-Oceania numerical experiment shows that the proposed sustainable collaborative transportation model can be efficiently solved by C++ calling ILOG CPLEX. Results demonstrate that the optimized shipping line network with sustainable collaborative transportation can improve the service efficiency, as well as the service level of shipping companies.

  17. The liner shipping berth scheduling problem with transit times

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander; Plum, Christian E.M.; Pisinger, David

    2016-01-01

    In this paper speed optimization of an existing liner shipping network is solved by adjusting the port berth times. The objective is to minimize fuel consumption while retaining the customer transit times including the transhipment times. To avoid too many changes to the time table, changes of port...... berth times are only accepted if they lead to savings above a threshold value. Since the fuel consumption of a vessel is a non-linear convex function of the speed, it is approximated by a piecewise linear function. The developed model is solved using exact methods in less than two minutes for large...

  18. The Vessel Schedule Recovery Problem (VSRP) – A MIP model for handling disruptions in liner shipping

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Dirksen, Jakob; Pisinger, David

    2013-01-01

    Containerized transport by liner shipping companies is a multi billion dollar industry carrying a major part of the world trade between suppliers and customers. The liner shipping industry has come under stress in the last few years due to the economic crisis, increasing fuel costs, and capacity...

  19. Designing robust liner shipping schedules: Optimizing recovery actions and buffer times

    NARCIS (Netherlands)

    J. Mulder (Judith); R. Dekker (Rommert); M. Sharifyazdi (Mehdi)

    2012-01-01

    textabstractMaritime transport is an important mode of transport in international trade. It is important for liner shipping companies to maintain cost efficient and robust liner shipping networks. Regularly, they set up pro-forma schedules, yet it is difficult to stay on time and we consider the

  20. A Matheuristic for the Liner Shipping Network Design Problem with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Karsten, Christian Vad;

    2015-01-01

    We present a mathematical model for the liner shipping network design problem with transit time restrictions on the cargo flow. We extend an existing matheuristic for the liner shipping network design problem to consider transit time restrictions. The matheuristic is an improvement heuristic, where...... on the benchmark suite LINER-LIB are reported, showing profitable networks for most instances. We provide insights on causes for rejecting demand and the average speed per vessel class in the solutions obtained....

  1. An integer programming model and benchmark suite for liner shipping network design

    DEFF Research Database (Denmark)

    Løfstedt, Berit; Alvarez, Jose Fernando; Plum, Christian Edinger Munk

    along with a rich integer programming model based on the services, that constitute the fixed schedule of a liner shipping company. The model may be relaxed as well as decomposed. The design of a benchmark suite of data instances to reflect the business structure of a global liner shipping network......Maritime transportation is accountable for 2.7% of the worlds CO2 emissions and the liner shipping industry is committed to a slow steaming policy to provide low cost and environmentally conscious global transport of goods without compromising the level of service. The potential for making cost...... effective and energy efficient liner shipping networks using operations research is huge and neglected. The implementation of logistic planning tools based upon operations research has enhanced performance of both airlines, railways and general transportation companies, but within the field of liner...

  2. A Path Based Model for a Green Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Jepsen, Mads Kehlet; Plum, Christian Edinger Munk;

    Liner shipping networks are the backbone of international trade providing low transportation cost, which is a major driver of globalization. These networks are under constant pressure to deliver capacity, cost eectiveness and environmentally conscious transport solutions. This article proposes a ...

  3. A Path Based Model for a Green Liner Shipping Network Design Problem

    OpenAIRE

    Mads K. Jepsen; Berit Lofstedt; Christian E. M. Plum; David Pisinger; Mikkel M. Sigurd

    2011-01-01

    Liner shipping networks are the backbone of international trade providing low transportation cost, which is a major driver of globalization. These networks are under constant pressure to deliver capacity, cost effectiveness and environmentally conscious transport solutions. This article proposes a new path based MIP model for the Liner shipping Network Design Problem minimizing the cost of vessels and their fuel consumption facilitating a green network. The proposed model reduces problem size...

  4. A path based model for a green liner shipping network design problem

    DEFF Research Database (Denmark)

    Jepsen, Mads Kehlet; Brouer, Berit Dangaard; Plum, Christian Edinger Munk

    2011-01-01

    Liner shipping networks are the backbone of international trade providing low transportation cost, which is a major driver of globalization. These networks are under constant pressure to deliver capacity, cost effectiveness and environmentally conscious transport solutions. This article proposes...... a new path based MIP model for the Liner shipping Network Design Problem minimizing the cost of vessels and their fuel consumption facilitating a green network. The proposed model reduces problem size using a novel aggregation of demands. A decomposition method enabling delayed column generation...

  5. A Matheuristic for the Liner Shipping Network Design Problem with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Karsten, Christian Vad

    2015-01-01

    We present a mathematical model for the liner shipping network design problem with transit time restrictions on the cargo flow. We extend an existing matheuristic for the liner shipping network design problem to consider transit time restrictions. The matheuristic is an improvement heuristic, where...... an integer program is solved iteratively as a move operator in a large-scale neighborhood search. To assess the effects of insertions/removals of port calls, flow and revenue changes are estimated for relevant commodities along with an estimation of the change in the vessel cost. Computational results...... on the benchmark suite LINER-LIB are reported, showing profitable networks for most instances. We provide insights on causes for rejecting demand and the average speed per vessel class in the solutions obtained....

  6. System Dynamics Modeling for Determining Optimal Ship Sizes and Types in Coastal Liner Services

    Directory of Open Access Journals (Sweden)

    Sung-il Park

    2014-04-01

    Full Text Available The problem of determining the required ship investment for deployment is an ongoing problem faced by governments and ship operators. The nature of ship investment is capital-intensive and the return on investment is often take long time. This paper attempts to establish system dynamics modeling (SDM to simulate and solve this problem in order to help ship operators make effective strategic decisions. A case study of coastal liner services between Incheon and Baengnyeong Island in South Korea was performed. Using scenario analysis, the possible ship sizes (small: 350 tons; large: 2,500 tons and types (new or used were considered by comparing potential revenue with costs. The results indicated that putting a used large-sized ship into operation would accommodate the increasing passenger and cargo volumes, and improve customer services.

  7. The Costs of Container Transport Flow Between Far East and Serbia Using Different Liner Shipping Services

    Directory of Open Access Journals (Sweden)

    Rajkovic Radoslav

    2015-11-01

    Full Text Available Liner shipping is the most efficient mode of transport for goods. International liner shipping is a sophisticated network of regularly scheduled services that transports goods from anywhere in the world to anywhere in the world at low cost and with greater energy efficiency than any other form of international transportation. Liner shipping connects countries, markets, businesses and people, allowing them to buy and sell goods on a scale not previously possible. Today, the liner shipping industry transports goods representing approximately one-third of the total value of global trade. Ocean shipping contributes significantly to international stability and security. Considering the large and constant struggle in the market in terms of competitive pricing of products, a very important and indispensable role represents the container transport with a clear task to define the final price of the product. This paper analyzes the costs of container transport flow between Far East and Serbia, using different liner shipping services, observing the six world’s largest container operators (Maersk Line, Mediterranean Shipping Company, CMA CGM, Evergreen Line, China Ocean Shipping Company and Hapag-Lloyd and inland (truck-rail-river transport corridors. These corridors include distance between selected Mediterranean ports (Koper, Rijeka, Bar, Thessaloniki, Constanta and Serbia. As a result, in this paper is considered a mathematical model that provides a comparative analysis of transportation costs on the different routes. It is observed already existing transport routes and it is also given hypothetical review to the development of new transport routes. The main goal of this research is to provide an optimal route with lowest transportation cost during container transport. Selection of the best route in the intermodal network is a very difficult and complex task. The costs in all modes of transport and the quality of their services are not constant

  8. Modeling and Solving the Liner Shipping Service Selection Problem

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Balakrishnan, Anant

    served less shipping costs. We propose a new hop-constrained multi-commodity arc flow model for the LSSSP that is based on an augmented network containing, for each candidate route, an arc (representing a sub-path) between every pair of ports that the route visits. This sub-path construct permits us...... to accurately model transshipment costs and incorporate routing policies such as maximum transit time, maritime cabotage rules, and operational alliances. Our hop-indexed arc flow model is smaller and easier to solve than path flow models. We outline a preprocessing procedure that exploits both the routing...

  9. Hub location problems in transportation networks

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan

    2011-01-01

    In this paper we propose a 4-index formulation for the uncapacitated multiple allocation hub location problem tailored for urban transport and liner shipping network design. This formulation is very tight and most of the tractable instances for MIP solvers are optimally solvable at the root node....... also introduce fixed cost values for Australian Post (AP) dataset....

  10. Single string planning problem arising in liner shipping industries: A heuristic approach

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Neamatian Monemi, Rahimeh; Mahey, Philippe

    2013-01-01

    We propose an efficient heuristic approach for solving instances of the Single String Planning Problem (SSPP) arising in the liner shipping industry. In the SSPP a Liner Service Provider (LSP) only revises one of its many operational strings, and it is assumed that the other strings...... are unchangeable. A string is a service route composed of a sequence of port calls—a call is a visit to a port followed by loading/unloading operations made by a vessel. In a string the vessel's round trip terminates at the same port that it started from, and the port calls follow a published itinerary. The SSPP...... out in the form of a controlled re-sequencing, insertion and elimination of ports from along the current string, given a set of ports limited to those that exist on the string and a set of potential ones. The outcome determines the required capacity, service level (frequency), call sequence, etc...

  11. A greedy construction heuristic for the liner service network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard

    The Liner Service Network Design Problem (LSN-DP) is the problem of constructing a set of routes for a heterogeneous vessel fleet of a global liner shipping operator. Routes in the liner shipping context are non-simple, cyclic routes constructed for a specific vessel type. The problem...... is challenging due to the size of a global liner shipping operation and due to the hub-and-spoke network design, where a high percentage of the total cargo is transshipped. We present the first construction heuristic for large scale instances of the LSN-DP. The heuristic is able to find a solution for a real...

  12. Pre-announcements of price increase intentions in liner shipping spot markets

    DEFF Research Database (Denmark)

    Chen, Gang; Rytter, Niels G M; Jiang, Liping;

    2017-01-01

    ’ attempts to restore profitability against overcapacity. However, out of all the GRI events only 28.6% were observed to be successful. Since these GRI successes must be the results of either price collusion (if any) and/or normal rate change by carriers in response to fundamental market developments......Carriers in liner shipping markets frequently make public announcements of general rate increase (GRI) intentions, based on which EU authorities have concerns as to whether this harms market competition. This paper aims to empirically investigate how well the GRI system works from an industrial...... factors, in sequence of explanation power, are the total capacity of GRI carriers, the idling fleet size, the spot rate level, and the average ship-loading factor. Clearly the latter three factors are market fundamentals, which are unlikely to be influenced by an individual carrier in the short term...

  13. Modeling Liner Shipping Service Selection and Container Flows using a Multi-layer Network

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Balakrishnan, Anant

    We introduce a new formulation for the tactical planning problem facing container shipping companies of selecting the best subset of sailing routes from a given pool of candidate routes so as to maximize profit. Since most containers are sent directly or transshipped at most twice in current liner...... shipping networks, we impose limits on the number of transshipments for each container (which most previous models do not incorporate). Our multi-layer multi-commodity model associates one commodity with each container origin port, and decides the route for each commodity on a logical network layer whose...... arcs represent segments (pairs of ports between which a container can use a single service). This approach, combined with commodity flow variables that are indexed by segment sequence permits us to incorporate the transshipment limits while also tracking the commodity’s outflow from the system...

  14. Modelling the impact of liner shipping network perturbations on container cargo routing: Southeast Asia to Europe application.

    Science.gov (United States)

    Achurra-Gonzalez, Pablo E; Novati, Matteo; Foulser-Piggott, Roxane; Graham, Daniel J; Bowman, Gary; Bell, Michael G H; Angeloudis, Panagiotis

    2016-06-03

    Understanding how container routing stands to be impacted by different scenarios of liner shipping network perturbations such as natural disasters or new major infrastructure developments is of key importance for decision-making in the liner shipping industry. The variety of actors and processes within modern supply chains and the complexity of their relationships have previously led to the development of simulation-based models, whose application has been largely compromised by their dependency on extensive and often confidential sets of data. This study proposes the application of optimisation techniques less dependent on complex data sets in order to develop a quantitative framework to assess the impacts of disruptive events on liner shipping networks. We provide a categorization of liner network perturbations, differentiating between systemic and external and formulate a container assignment model that minimises routing costs extending previous implementations to allow feasible solutions when routing capacity is reduced below transport demand. We develop a base case network for the Southeast Asia to Europe liner shipping trade and review of accidents related to port disruptions for two scenarios of seismic and political conflict hazards. Numerical results identify alternative routing paths and costs in the aftermath of port disruptions scenarios and suggest higher vulnerability of intra-regional connectivity.

  15. An algorithm for solving the time-constrained multicommodity flow problem with applications in liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Pisinger, David; Røpke, Stefan

    The liner shipping network design problem has proven to be hard to solve. However, well-designed route nets are paramount to liner shipping companies both in terms of competitiveness and environmental impact. Fast evaluations of the multicommodity flow subproblem is one of the bottlenecks when...... determining the optimal routing and fleet deployment in the network design problem. Additionally, most existing models do not consider the level of service. To accommodate that, we present an algorithm for solving the multicommodity flow subproblem with limits on commodity travel time....

  16. An algorithm for solving the time-constrained multicommodity flow problem with applications in liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Pisinger, David; Røpke, Stefan

    The liner shipping network design problem has proven to be hard to solve. However, well-designed route nets are paramount to liner shipping companies both in terms of competitiveness and environmental impact. Fast evaluations of the multicommodity flow subproblem is one of the bottlenecks when...... determining the optimal routing and fleet deployment in the network design problem. Additionally, most existing models do not consider the level of service. To accommodate that, we present an algorithm for solving the multicommodity flow subproblem with limits on commodity travel time....

  17. Liner ship refueled strategy considering ship speed%考虑船舶航速的集装箱班轮燃油补给策略

    Institute of Scientific and Technical Information of China (English)

    饶明君; 杨斌; 朱小林; 许波桅

    2015-01-01

    针对集装箱班轮运输中船舶燃油补给问题,分析船舶航速变化对燃油消耗产生的非线性影响,推导出船舶航速与船舶往返时间及船舶油耗之间的关系式,以连续多航次船舶燃油补给总成本最低为目标,加油港与加油量为决策变量,建立周计划内考虑航速的集装箱班轮燃油补给混合整数非线性规划模型。根据模型特点,利用分段线性逼近函数对模型进行等价转换。以某航运公司的亚欧单航线为仿真实验,依次分析港口时间窗、船舶类型、燃油价格及船舶油舱容量等因素对船舶燃油补给策略的影响。结果表明:该模型可以同时决策船舶加油港的选择、加油量的大小及航速的调整,比传统模式更能节省油耗和成本。%In view of the problems of ship′s refueling strategy in container liner transportation network , analysis of the non-linear influence of ship speed on fuel consumption is done and the mathematical functions are deduced to describe the relationships between the ship speed , fuel consumption and the round voyage time .To minimize the ship refueling cost , a mixed integer non-linear programming model considering ship speed is formulated to solve the optimal refueling strategy problem of where to refuel and how much to fuel .According to the characteristics of the model , we utilize piecewise linear approximation function for equivalent model .The single shipping liner service of Asia-Europe is taken as an example for the simulation experiment , the sequence analysis is made of port arrival time windows , and ship type , bunker fuel price , and ship bunker fuel capacity on bunker fuel supply strategy .The results indicate that the proposed model , compared with the conventional model , can simultaneously solve the problems of bunkering port , bunkering amounts and ship speeds adjustment , save fuel consumption and cost .

  18. Freight integration in liner shipping: a strategy serving global production networks

    OpenAIRE

    Notteboom, T.; Merckx, F.

    2006-01-01

    Container shipping lines are well aware of the growing importance of global production networks. While continuing to focus on improving the fundamentals, many shipping lines have developed a keen interest in other segments of the logistics and transportation market to offer integrated and worldwide services to global production networks. This paper aims to assess the overall level of freight integration in thirty-four shipping lines, and provides an insight into the extent to which freight in...

  19. MELINIKOV'S METHOD FOR NON-LINER ROLLING MOTIONS OF A FLOODED SHIP

    Institute of Scientific and Technical Information of China (English)

    PU Jin-yun; ZHANG Wei-kang; JIN Tao; JI Gang

    2005-01-01

    To investigate the rolling motions of a flooded ship, non-linear coupled dynamics of roll and flooded water are derived using Lagrange's principle. Decoupling the coupled equations gives a single-freedom ordinary differential equation, which can describe the rolling motion of the flooded ship. Melinkov's method is used to predict the chaos behavior of the ship. Numerical computations are performed for three statuses of a ship model. The comparison of the results shows that the more cabins flooded, the more likely a chaos phenomenon will appear.

  20. Liner Service Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard

    This thesis concerns design of liner shipping networks using operations research to optimize liner shipping networks at the strategic, tactical and operational level. Liner shipping networks are often compared to public transit networks as they consist of a set of scheduled sailings connecting....... The research field of liner shipping network design is relatively young and many open research questions exists. Among others, a unified and rich mathematical model formulating the main characteristics of the business domain has not been clearly described and exact methods for such mathematical models...... are still not able to solve significant instances of this complex optimization problem. In this thesis two research directions are explored within the field: The first research direction contributes to basic research on the liner shipping network design problem by describing the domain seen from...

  1. The Logistic of Empty Containers′ Return in the Liner-Shipping Network

    Directory of Open Access Journals (Sweden)

    Belayachi Naima

    2017-09-01

    Full Text Available The Maritime Transport is a favoured tool regarding the universal exchanges because it has gone through several evolutions. Indeed, the containerization is considered as one of the most remarkable improvements in the shipping. The containers are rented by shipping companies. However, these companies meet an empty container availability problem at some ports of Maritime Transport Network (MTN to satisfy the demands of clients. The objective of this work is to solve the problem of the imbalance of the distribution of containers and look for empty containers at less cost to meet the demands of clients. As a result, the authors propose an application to represent the MTN, and provide a balanced distribution of containers. The work presented in this article is based on a heuristic method by neighbourhood. It allows the process of the clients' demands and transfers of full containers as well as the research of empty containers by optimizing the cost of theirs return.

  2. 亚洲集装箱港口的全球班轮网络地位%Position of the Asian Container Ports in Global Liner Shipping Network

    Institute of Scientific and Technical Information of China (English)

    李振福; 史砚磊; 徐梦俏; 张小玲

    2016-01-01

    As the container shipping system is improved,competition among those container ports is getting much intense,thus results a differentiation in their positions in global liner shipping.Based on centrality indicators for node importance from complex network theory,this paper assesses the position of the Asian container ports from a perspective of global liner service network.Through degree analysis,strength analysis and eigenvector analysis in the liner service networks of COSCON and Maersk line,we find that the positions of Shanghai,Singapore,Shenzhen,Ningbo,Hong Kong and Busan are relatively high,meanwhile Chinese ports such as Guangzhou,Tianjin and Dalian are of great potentials.Finally,some suggestions for the development of Chinese ports are put forward according to the results in this paper.%运用复杂网络理论中节点重要性的分析方法,从班轮公司全球海运服务网络的角度对亚洲集装箱港口的地位进行评估.通过对中远集运和马士基全球班轮海运服务网络中港口节点的度、点强度和特征向量指标计算,发现上海、新加坡、深圳、宁波、香港和釜山几个亚洲港口在两个网络中都具有很高的地位;同时,广州、天津、大连等中国港口存在较大的发展潜力.最后,为中国港口的发展提出了建议.

  3. An investigation of forecast horizon and observation fit’s influence on an econometric rate forecast model in the liner shipping industry

    DEFF Research Database (Denmark)

    Nielsen, Peter; Jiang, Liping; Rytter, Niels Gorm Malý

    2014-01-01

    This paper evaluates the influence of forecast horizon and observation fit on the robustness and performance of a specific freight rate forecast model used in the liner shipping industry. In the first stage of the research, a forecast model used to predict container freight rate development...... of the forecast horizon and observation fit and their interactions on the forecast model's performance. The results underline the complicated nature of creating a suitable forecast model by balancing business needs, a desire to fit a good model and achieve high accuracy. There is strong empirical evidence from...... this study; that a robust model is preferable, that overfitting is a true danger, and that a balance must be achieved between forecast horizon and the number of observations used to fit the model. In addition, methodological guidance has also been provided on how to test, design, and choose the superior...

  4. 基于市场细分的集装箱班轮运输舱位分配%Container Liner Shipping Slot Allocation Based on Market Segmentation

    Institute of Scientific and Technical Information of China (English)

    杨华龙; 夏秋; 刘迪

    2013-01-01

    To optimization of slot allocation of container liner shipping the theories of revenue management and market segmentation is applied. The container liner shipping market is divided into general customer segment and rush customer segment according to its heterogeneous aspect. The Prob function and NORMINV function are employed to obtain the amount of preserved slots for each part of the multi-ports route for the rush customer segment and the necessary amount of slots needed for general customer segment. With the priciple, a random programming model for the container slot allocation with the allocation and transport of empty containers is established and its relevant algorithm is designed. Example analysis shows the effectiveness of the model and of the algorithm.%为解决集装箱班轮运输的舱位分配优化问题,运用收益管理和市场细分理论,根据客户的异质性将集装箱班轮运输市场细分为普通客户市场和加急客户市场,利用Prob函数和NORMINV函数计算出多港挂靠航线某航次各航段上加急客户市场应预留的舱位数量以及可以接受普通客户订舱的舱位数量.在此基础上,建立了包含空箱调运问题的舱位分配随机规划模型,设计了相应的算法,算例分析显示了该模型及算法的有效性.

  5. PORTS WRESTLE FOR HUB STATUS

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Due to the fact that there has been nocontainer transport hub port in NorthernChina,northern ports are striving fordevelopment and trying to secure a positionof being the hub port in Northern Chinaahead of others. According to media reports,EasternChina’s Shandong Province will invest 5billion yuan(US$604 million)in buildinga Qingdao international shipping hub thatisbased on existing ports in theShandong Peninsula.

  6. Shipping noise in whale habitat: Characteristics, sources, budget, and impact on belugas in Saguenay-St. Lawrence Marine Park hub

    OpenAIRE

    Gervaise, Cedric; Simard, Yvan; Roy, Nathalie; Kinda, Bazile; Menard, Nadia

    2012-01-01

    WOS; International audience; A continuous car ferry line crossing the Saguenay Fjord mouth and traffic from the local whale-watching fleet introduce high levels of shipping noise in the heart of the Saguenay-St. Lawrence Marine Park. To characterize this noise and examine its potential impact on belugas, a 4-hydrophone array was deployed in the area and continuously recorded for five weeks in May-June 2009. The source levels of the different vessel types showed little dependence on vessel siz...

  7. The time constrained multi-commodity network flow problem and its application to liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Pisinger, David; Røpke, Stefan

    2015-01-01

    The multi-commodity network flow problem is an important sub-problem in several heuristics and exact methods for designing route networks for container ships. The sub-problem decides how cargoes should be transported through the network provided by shipping routes. This paper studies the multi......-commodity network flow problem with transit time constraints which puts limits on the duration of the transit of the commodities through the network. It is shown that for the particular application it does not increase the solution time to include the transit time constraints and that including the transit time...

  8. Shipping

    NARCIS (Netherlands)

    Wijnolst, N.; Wergeland, T.

    1996-01-01

    Shipping is a multi-faceted industry which is rather complex to define from an academic point of view. This book attempts to grasp these complexities and provide the reader with an overview of the main topics and terminology in shipping. The book is based on material from our courses in shipping at

  9. Solving Hub Network Problem Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mursyid Hasan Basri

    2012-01-01

    Full Text Available This paper addresses a network problem that described as follows. There are n ports that interact, and p of those will be designated as hubs. All hubs are fully interconnected. Each spoke will be allocated to only one of available hubs. Direct connection between two spokes is allowed only if they are allocated to the same hub. The latter is a distinct characteristic that differs it from pure hub-and-spoke system. In case of pure hub-and-spoke system, direct connection between two spokes is not allowed. The problem is where to locate hub ports and to which hub a spoke should be allocated so that total transportation cost is minimum. In the first model, there are some additional aspects are taken into consideration in order to achieve a better representation of the problem. The first, weekly service should be accomplished. Secondly, various vessel types should be considered. The last, a concept of inter-hub discount factor is introduced. Regarding the last aspect, it represents cost reduction factor at hub ports due to economies of scale. In practice, it is common that the cost rate for inter-hub movement is less than the cost rate for movement between hub and origin/destination. In this first model, inter-hub discount factor is assumed independent with amount of flows on inter-hub links (denoted as flow-independent discount policy. The results indicated that the patterns of enlargement of container ship size, to some degree, are similar with those in Kurokawa study. However, with regard to hub locations, the results have not represented the real practice. In the proposed model, unsatisfactory result on hub locations is addressed. One aspect that could possibly be improved to find better hub locations is inter-hub discount factor. Then inter-hub discount factor is assumed to depend on amount of inter-hub flows (denoted as flow-dependent discount policy. There are two discount functions examined in this paper. Both functions are characterized by

  10. Solving Hub Network Problem Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mursyid Hasan Basri

    2012-01-01

    Full Text Available This paper addresses a network problem that described as follows. There are n ports that interact, and p of those will be designated as hubs. All hubs are fully interconnected. Each spoke will be allocated to only one of available hubs. Direct connection between two spokes is allowed only if they are allocated to the same hub. The latter is a distinct characteristic that differs it from pure hub-and-spoke system. In case of pure hub-and-spoke system, direct connection between two spokes is not allowed. The problem is where to locate hub ports and to which hub a spoke should be allocated so that total transportation cost is minimum. In the first model, there are some additional aspects are taken into consideration in order to achieve a better representation of the problem. The first, weekly service should be accomplished. Secondly, various vessel types should be considered. The last, a concept of inter-hub discount factor is introduced. Regarding the last aspect, it represents cost reduction factor at hub ports due to economies of scale. In practice, it is common that the cost rate for inter-hub movement is less than the cost rate for movement between hub and origin/destination. In this first model, inter-hub discount factor is assumed independent with amount of flows on inter-hub links (denoted as flow-independent discount policy. The results indicated that the patterns of enlargement of container ship size, to some degree, are similar with those in Kurokawa study. However, with regard to hub locations, the results have not represented the real practice. In the proposed model, unsatisfactory result on hub locations is addressed. One aspect that could possibly be improved to find better hub locations is inter-hub discount factor. Then inter-hub discount factor is assumed to depend on amount of inter-hub flows (denoted as flow-dependent discount policy. There are two discount functions examined in this paper. Both functions are characterized by

  11. Innovation hubs

    DEFF Research Database (Denmark)

    O´Hara, J.; Hansen, Poul H. Kyvsgård; Turner, N.

    2008-01-01

    "Whilst ‘incremental innovation' is an imperative for the short-to-medium term success of a company, there is also a need for companies to engage in innovation activity that goes beyond the incremental in order to guarantee long-term success. However, such ‘radical innovation' (RI) poses new...... challenges and requires new competencies, some of which may conflict with existing best-practices for incremental innovations. ‘Innovation hubs' are a type of organisational structure dedicated to RI projects that have been used by companies to manage these conflicts by maintaining a certain degree...... of separation from the culture and routines of the mainstream organisation. Unfortunately, it would appear that many attempts to set-up innovation hubs have ended in failure within a few years; not before considerable time, effort and resource has been expended. This paper reports on a study of six innovation...

  12. Innovation hubs

    DEFF Research Database (Denmark)

    O´Hara, J.; Hansen, Poul H. Kyvsgård; Turner, N.

    2008-01-01

    "Whilst ‘incremental innovation' is an imperative for the short-to-medium term success of a company, there is also a need for companies to engage in innovation activity that goes beyond the incremental in order to guarantee long-term success. However, such ‘radical innovation' (RI) poses new...... challenges and requires new competencies, some of which may conflict with existing best-practices for incremental innovations. ‘Innovation hubs' are a type of organisational structure dedicated to RI projects that have been used by companies to manage these conflicts by maintaining a certain degree...... of separation from the culture and routines of the mainstream organisation. Unfortunately, it would appear that many attempts to set-up innovation hubs have ended in failure within a few years; not before considerable time, effort and resource has been expended. This paper reports on a study of six innovation...

  13. 碳排放权交易下的班轮船队配置优化研究%Optimization of Liner Ship Fleet Mix Strategy under Emission Trading System

    Institute of Scientific and Technical Information of China (English)

    朱墨; 真虹; 甘爱平

    2016-01-01

    With the trend of imposing market-based mechanisms in shipping industry, this paper proposes an optimization model for liner ship fleet mix strategy under carbon emission trading system, which minimizes the total expected operational costs in multiple periods. The uncertain carbon emission allowance price is described by Geometric Brownian Motion. A numerical experiment with real industrial data is carried out to analyze optimized fleet mix strategy and carbon emission volume. Result shows that by involving liner companies into emission trading system, fleet carbon emissions can be reduced significantly, while companies need to pay for the allowances purchase. Another conclusion that based on sensitivity analysis of bunker prices shows:the impact of emission trading system on motivation to use energy-efficient ships and fleet carbon mitigation increases along with the rising of bunker price.%针对集装箱班轮运输企业建立考虑碳排放权交易机制的船队配置优化模型,以期实现船队营运成本最小化。采用几何布朗运动描述欧洲碳排放权交易价格的波动路径,以使决策根据变化的碳交易价格做出。收集班轮业营运数据设计案例,验证了模型能够应用于实例分析。算例结果显示,即使在近期较低的欧洲碳交易价格水平下,在集装箱班轮行业中实施碳交易机制仍能取得明显的减排效果,但企业也需付出一定的费用;针对燃油价格做敏感性分析得出,随着燃油价格的上升,碳交易机制对促进减排的效果也越加显著。

  14. The US Cruise Ship Industry.

    Science.gov (United States)

    Miller, Willis H.

    1985-01-01

    The cruise ship industry relates directly to many features of the natural and cultural environments. The U.S. cruise ship industry is analyzed. Discusses the size of the industry, precruise passenger liners, current cruise ships, cruise regions and routes, ports of call, major ports, passengers, and future prospects. (RM)

  15. Natural Gas Market Hubs

    Data.gov (United States)

    Department of Homeland Security — A hub is a physical transfer point for natural gas where several pipelines are connected. A market center is a hub where the operator offers services that facilitate...

  16. Quadratic Assignment of Hubs in p-Hub Median Problem

    DEFF Research Database (Denmark)

    Gelareh, Shahin

    We introduce Generalized p-Hub Median Problem (GpHMP) that seeks to locate p hub nodes and install p distinct hub facilities/operators on the hubs while discount factor resulted by consolidation of flow on the hub links depends on the facilities/operators that are installed/operating on both hub...... nodes end-point. In contrast, in traditional hub location problems it is commonly assumed that all the hub facilities share a similar characteristic and economy of scale resulted by consolidation of flow over hub edges is not directly relevant to the hub facilities being installed at both end...

  17. Virtual Campus Hub technology

    DEFF Research Database (Denmark)

    Vercoulen, Frank; Badger, Merete; Monaco, Lucio;

    This deliverable briefly describes which technological components have been delivered for the Virtual Campus Hub and how they can be used. A detailed discussion of the technical details of the components, how they were realized and how they fit the VCH concept can be found in deliverables D5.......4. Virtual Campus Hub Technology Evaluation Report and D6.7 The Virtual Campus Hub Concept....

  18. Aircraft Propeller Hub Repair

    Energy Technology Data Exchange (ETDEWEB)

    Muth, Thomas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peter, William H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-02-13

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spray coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.

  19. Cargo-mix optimization in Liner Shipping

    DEFF Research Database (Denmark)

    Christensen, Jonas Mark; Pacino, Dario; Fonseca, Joao Filipe Paiva

    , it is hard tomotivate companies to pay for cleaner transport since transportation is not visible to end customers,and therefore cannot justify a higher cost. Hence, optimization may be one of the few options forlimiting CO2 emission of international trade. A possible direction is to focus on vessels...... composition available in the different portsmight not be suitable for the full utilization of the vessel. The focus of our work is the analysis ofvessels’ cargo-mix, in particular finding what cargo composition is needed for a vessel to maximizeits utilization on a given service. Such a model can have various...... applications ranging from drivingrate prices, improving fleet composition and network design ((Christiansen et al., 2007; Reinhardtand Pisinger, 2012; Brouer et al., 2014))....

  20. Twin Hub Network (poster)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.

    2014-01-01

    Twin hub network, a European Interreg IVB project, aims at making intermodal rail transport within, to and from North West Europe more competitive, in particular between seaports and inland terminals. Improving rail competitiveness enables to shift freight flows from road to rail, providing a more s

  1. Shipping lines and logistics

    OpenAIRE

    FREMONT, A

    2006-01-01

    For some time it has been acknowledged that logistics is a driving force that shapes the integration of the transport chain. This paper argues that while the liner shipping industry exhibits increased horizontal integration, its vertical integration remains limited. A clear distinction is drawn between freight logistics, container logistics and vessel logistics. Freight logistics is defined as part of the supply chain process, the focus of which are the goods being transported. The purpose of...

  2. Poststarburst Models of LINERs

    CERN Document Server

    Taniguchi, Y; Murayama, T; Taniguchi, Yoshiaki; Shioya, Yasuhiro; Murayama, Takashi

    2000-01-01

    Since the discovery of low-ionization nuclear emission-line regions in many galaxies (LINERs), it has been recognized that they constitute a class of active galactic nuclei (AGNs) which are thought to be powered by gas accretion onto a central, supermassive black hole. LINERs are observed in approximately one third of galaxies in the local universe and it has been often thought that they harbor an AGN-like central engine with moderate activity. However, some LINERs show no direct evidence for AGNs such as broad emission lines, radio jets, hard X-ray emission, spectral energy distributions which are inconsistent with starlight, and so on. For such LINERs (a subset of type 2 LINERs), we present new poststarburst models which explain some of their most important optical narrow emission-line ratios. In these models, the ionization sources are planetary nebula nuclei (PNNs) with temperature of ~ 10^5 K which appear in the late-phase evolution of intermediate-mass stars with mass between ~ 3 M_solar and ~ 6 M_solar...

  3. Perl one-liners

    CERN Document Server

    Krumins, Peteris

    2013-01-01

    130 Time-Saving, Problem-Solving Perl Scripts That Get Things DonePart of the fun of programming in Perl lies in tackling tedious tasks with short, efficient, and reusable code. Often, the perfect tool is the one-liner, a small but powerful program that fits in one line of code and does one thing really well.In Perl One-Liners, author and impatient hacker Peteris Krumins takes you through more than 100 compelling one-liners that do all sorts of handy things, such as manipulate line spacing, tally column values in a table, and get a list of users on a system. This cookbook of useful, customizab

  4. Routing and Scheduling in Tramp Shipping - Integrating Bunker Optimization

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte; Lusby, Richard Martin; Larsen, Jesper

    A tramp ship operator typically has some contracted cargoes that must be carried and seeks to maximize pro_t by carrying optional cargoes. Hence, tramp ships operate much like taxies following available cargoes and not according to a _xed route network and itinerary as liner ships. Marine fuel...

  5. RFID-based smart logistics management system for supply hub in industrial park (SHIP)%基于RFID的工业园区SHIP智能物流管理系统

    Institute of Scientific and Technical Information of China (English)

    宁晓菊; 陈艳; 朱伟军; 屈挺; 黄国全

    2014-01-01

    对园区企业的生产物料进行统一存储是工业园区公共仓库(SHIP,Supply Hub in Industrial Park)的基本功能;而采用Milk-run公共物流模式为多企业提供循环式JIT集中物料配送,则是SHIP服务的高级阶段。这种由分布式产线实时需求驱动的协同式精益化物流运作对物流资源的有效性、配送路径的经济性、交接数据的精确性等提出了较高的实时性管理要求。本文综合运用RFID等物联网技术及先进的智能终端、地理信息及优化统计技术,开发一套以SHIP为核心的工业园区公共物流智能化管理服务系统,辅助园区多制造企业进行集成化、协同化和智能化的动态仓储管理和实时物流管理。

  6. Transport hub flow modelling

    OpenAIRE

    Despagne, Wilfried; Frenod, Emmanuel

    2014-01-01

    Purpose: The purpose of this paper is to investigate the road freight haulage activity. Using the physical and data flow information from a freight forwarder, we intend to model the flow of inbound and outbound goods in a freight transport hub. Approach: This paper presents the operation of a road haulage group. To deliver goods within two days to any location in France, a haulage contractor needs to be part of a network. This network handles the processing of both physical goods and data. We...

  7. GitHub Android

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    代码托管仓库GitHub发布了官方,Android客户端,手机和平板用户可以从GoogleP1ay下载。它的出现,将方便更多用户融入GitHub社区。GitHubAndroid本身也是开源软件,其源代码可以从GitHub浏览。此前,GitHub已经推出了Windows和Mac版客户端。

  8. Combustor liner construction

    Science.gov (United States)

    Craig, H. M.; Wagner, W. B.; Strock, W. J. (Inventor)

    1983-01-01

    A combustor liner is fabricated from a plurality of individual segments each containing counter/parallel Finwall material and are arranged circumferentially and axially to define the combustion zone. Each segment is supported by a hook and ring construction to an opened lattice frame with sufficient tolerance between the hook and ring to permit thermal expansion with a minimum of induced stresses.

  9. New approaches to the marine transport hub competitive growth

    Directory of Open Access Journals (Sweden)

    M. V. Botnaryuk

    2010-12-01

    Full Text Available The issues of marine transport hub competitive growth in the context of new economic conditions are considered in the paper. Analyzing the present tools of the transport hub competitive growth, the author emphasizes their production-logistics orientation. However, when rendering services to cargo and ship owners, members of the MTH establish official (contractual and informal relationship and exchange information on a permanent basis. The research into the nature of such a relationship brought the author to the conclusion that generation and further development of the partnership is a basis for new ways of the transport hub competitive growth. Considering the MTH as an institution, the author suggests that a general marketing information system intended for improvement of the services rendered, which will undeniably enhance competitive advantage.

  10. Indico: A Collaboration Hub

    CERN Document Server

    Ferreira, P; Bossy, C; Gonzalez, J B; Pugh, M; Resco, A; Trzaskoma, J; Wachter, C

    2012-01-01

    Since 2009, the development of Indico has focused on usability, performance and new features, especially the ones related to meeting collaboration. Usability studies have resulted in the biggest change Indico has experienced up to now, a new web layout that makes user experience better. Performance improvements were also a key goal since 2010; the main features of Indico have been optimized remarkably. Along with usability and performance, new features have been added to Indico such as webchat integration, video services bookings, webcast and recording requests, designed to really reinforce Indico position as the main hub for all CERN collaboration services, and many others which aim is to complete the conference lifecycle management. Indico development is also moving towards a broader collaboration where other institutes, hosting their own Indico instance, can contribute to the project in order make it a better and more complete tool.

  11. The Virtual Campus Hub Concept

    DEFF Research Database (Denmark)

    Badger, Merete; Prag, Sidsel-Marie Winther; Monaco, Lucio

    of Technology in Sweden, Politecnico di Torino in Italy, and Eindhoven University of Technology in the Netherlands. The project is partially funded by the European Commission under the 7th Framework Programme (project no. RI-283746). This report describes the final concept of Virtual Campus Hub. It gives...... an overview of the project achievements and recommends best practices for the use of the Virtual Campus Hub elements: a series of applications for online teaching and collaboration which are connected to a technical platform, the Virtual Campus Hub portal, using the European research infrastructure Géant/eduGAIN....

  12. A new transport hub

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    CERN’s new Mobility Centre, allowing you to switch easily from one mode of transport to another, has just been officially opened.   Inauguration of the CERN Mobility Centre by Martin Steinacher, Director for Finance and Human Resources, and Lluis Miralles, Head of the SMB department. CERN’s new Mobility Centre, on the car park next to the Globe of Science and Innovation was officially opened on Tuesday, 22 March. The centre brings together all of CERN’s transport options in a single location. "Our aim is to create an intermodal hub where CERN users and personnel can switch from one mode of transport to another, and from CERN transport to public transport," explains Lluis Miralles, head of the Site Management and Buildings (SMB) department. The Mobility Centre incorporates the CERN bike and car rental services, the self-service car- and bike-sharing schemes, and SIXT car rental facilities (for long-distance journeys). It is located right ne...

  13. Optimal Liner Material for Near Term Magnetized Liner Fusion Experiments

    Science.gov (United States)

    Slutz, Stephen

    2012-10-01

    Substantial fusion yields are predicted with existing pulsed power machines driving cylindrical liner implosions with preheated and magnetized deuterium-tritium [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)]. Experiments are planned using the Z accelerator to drive these implosions. However, the peak current, the laser heating energy, and the applied magnetic field will be less than optimal. We present simulations which show, that under these conditions, the yield can be improved significantly by decreasing the density of the liner material, e.g. Lithium substituted for Beryllium. Furthermore, the simulations show that decreasing the liner density allows the use of very low aspect ratio (R/δR) liners, while still obtaining interesting yields. Low aspect ratio liners should be more robust to the Rayleigh-Taylor instability.

  14. Risk assessment for the transportation of radioactive zeolite liners

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    The risk is estimated for the shipment of radioactive zeolite liners in support of the Zeolite Vitrification Demonstration Program currently underway at Pacific Northwest Laboratory under the sponsorship of the US Department of Energy. This program will establish the feasibility of zeolite vitrification as an effective means of immobilizing high-specific-activity wastes. In this risk assessment, it is assumed that two zeolite liners, each loaded around July 1, 1981 to 60,000 Ci, will be shipped by truck around January 1, 1982. However, to provide a measure of conservatism, each liner is assumed to initially hole 70,000 Ci, with the major radioisotopes as follow: /sup 90/Sr = 3000 Ci, /sup 134/Cs = 7000 Ci, /sup 137/Cs = 60,000 Ci. Should shipment take place with essentially no delay after initial loading (regardless of loading date), the shipment loading would be only 2.7% higher than that for the assumed six-month delay. This would negligibly affect the overall risk. As a result of this risk assessment, it is concluded that the transport of the radioactive zeolite liners from TMI to PNL by truck can be conducted at an insignificant level of risk to the public.

  15. Magnesium Fluoride Reduction Vessel Liners

    Science.gov (United States)

    1986-03-26

    Carolina Metals, the fluoride is reduced to power by means of a Mikro #2 hemmer mill (Figure 5). The material is then separated into the different...The jolter table previously referred to in the liner pro - ceasing operation, is the knockout station. As shown in Figure 36, the vessel is inverted...was much more extensive than normally performed to establish the quality of thý metal pro - duced using the MgF2 liners. There are no indications of

  16. FGD liner experiments with wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Mitsch, W.J.; Ahn, C.; Wolfe, W.E.

    1999-07-01

    The construction of artificial wetlands for wastewater treatment often requires impermeable liners not only to protect groundwater resources but also to ensure that there is adequate water in the wetland to support appropriate aquatic life, particularly wetland vegetation. Liners or relatively impervious site soils are very important to the success of constructed treatment wetlands in areas where ground water levels are typically close to the ground surface. This study, carried out at the Olentangy River Wetland Research Park, investigated the use of FGD material from sulfur scrubbers as a possible liner material for constructed wetlands. While several studies have investigated the use of FGD material to line ponds, no studies have investigated the use of this material as a liner for constructed wetlands. They used experimental mesocosms to see the effect of FGD liner materials in constructed wetlands on water quality and on wetland plant growth. This paper presents the results of nutrient analyses and physicochemical investigation of leachate and surface outflow water samples collected from the mesocosms. Plant growth and biomass of wetland vegetation are also included in this paper. First two year results are reported by Ahn et al. (1998, 1999). The overall goal of this study is the identification of advantages and disadvantages of using FGD by-product as an artificial liner in constructed wetlands.

  17. A competing risk model for the reliability of cylinder liners in marine Diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Bocchetti, D. [Grimaldi Group, Naples (Italy); Giorgio, M. [Department of Aerospace and Mechanical Engineering, Second University of Naples, Aversa (Italy); Guida, M. [Department of Information Engineering and Electrical Engineering, University of Salerno, Fisciano (Italy); Pulcini, G. [Istituto Motori, National Research Council-CNR, Naples (Italy)], E-mail: g.pulcini@im.cnr.it

    2009-08-15

    In this paper, a competing risk model is proposed to describe the reliability of the cylinder liners of a marine Diesel engine. Cylinder liners presents two dominant failure modes: wear degradation and thermal cracking. The wear process is described through a stochastic process, whereas the failure time due to the thermal cracking is described by the Weibull distribution. The use of the proposed model allows performing goodness-of-fit test and parameters estimation on the basis of both wear and failure data. Moreover, it enables reliability estimates of the state of the liners to be obtained and the hierarchy of the failure mechanisms to be determined for any given age and wear level of the liner. The model has been applied to a real data set: 33 cylinder liners of Sulzer RTA 58 engines, which equip twin ships of the Grimaldi Group. Estimates of the liner reliability and of other quantities of interest under the competing risk model are obtained, as well as the conditional failure probability and mean residual lifetime, given the survival age and the accumulated wear. Furthermore, the model has been used to estimate the probability that a liner fails due to one of the failure modes when both of these modes act.

  18. Estimating the sustainability of hubs

    NARCIS (Netherlands)

    Lieshout, R.; Zuidberg, J.; Veldhuis, J.

    2008-01-01

    Several airports in the world are or will be confronted with capacity problems in the near future. As a result of this congestion, many airports will face a selectivity problem: which traffic segments must be accommodated and which segments are less crucial? At hub airports there is generally one

  19. Beijing: Next International Financial Hub?

    Institute of Scientific and Technical Information of China (English)

    Li Zhen

    2008-01-01

    @@ Beijing's new financial dream On May 5,the Beijing Municipal Government released a notice regarding its plans to spur the financial industry,vowing to put forth a strong effort to become the national financial decision-making center,financial management center and financial information and services center,and formally announcing its ambitious aspiration to become a financial hub with international influence.

  20. Towards collaborative, intermodal hub networks. A case study in the fast moving consumer goods market

    NARCIS (Netherlands)

    Groothedde, B.; Ruijgrok, C.; Tavasszy, L.

    2005-01-01

    Collaborative hub networks can provide an answer to the need to decrease logistics cost and maintain logistics service levels by shifting consolidated flows to modes that are better suited for handling large volumes (rail, barge, coastal shipping), so economies of scale can be obtained. This necessi

  1. Towards collaborative, intermodal hub networks. A case study in the fast moving consumer goods market

    NARCIS (Netherlands)

    Groothedde, B.; Ruijgrok, C.; Tavasszy, L.

    2005-01-01

    Collaborative hub networks can provide an answer to the need to decrease logistics cost and maintain logistics service levels by shifting consolidated flows to modes that are better suited for handling large volumes (rail, barge, coastal shipping), so economies of scale can be obtained. This

  2. PolarHub: A Global Hub for Polar Data Discovery

    Science.gov (United States)

    Li, W.

    2014-12-01

    This paper reports the outcome of a NSF project in developing a large-scale web crawler PolarHub to discover automatically the distributed polar dataset in the format of OGC web services (OWS) in the cyberspace. PolarHub is a machine robot; its goal is to visit as many webpages as possible to find those containing information about polar OWS, extract this information and store it into the backend data repository. This is a very challenging task given huge data volume of webpages on the Web. Three unique features was introduced in PolarHub to make it distinctive from earlier crawler solutions: (1) a multi-task, multi-user, multi-thread support to the crawling tasks; (2) an extensive use of thread pool and Data Access Object (DAO) design patterns to separate persistent data storage and business logic to achieve high extendibility of the crawler tool; (3) a pattern-matching based customizable crawling algorithm to support discovery of multi-type geospatial web services; and (4) a universal and portable client-server communication mechanism combining a server-push and client pull strategies for enhanced asynchronous processing. A series of experiments were conducted to identify the impact of crawling parameters to the overall system performance. The geographical distribution pattern of all PolarHub identified services is also demonstrated. We expect this work to make a major contribution to the field of geospatial information retrieval and geospatial interoperability, to bridge the gap between data provider and data consumer, and to accelerate polar science by enhancing the accessibility and reusability of adequate polar data.

  3. Container shipping service selection and cargo routing with transshipment limits

    DEFF Research Database (Denmark)

    Balakrishnan, Anantaram; Karsten, Christian Vad

    2017-01-01

    We address the tactical planning problem faced by container liner shipping companies to select a set of sailing services from a given pool of candidate services and route available cargo over the chosen services so as to maximize profit. One of the distinctive features of our model is that it inc......We address the tactical planning problem faced by container liner shipping companies to select a set of sailing services from a given pool of candidate services and route available cargo over the chosen services so as to maximize profit. One of the distinctive features of our model...... solutions. We report successful computational results for realistic problem instances from a benchmark suite of liner shipping problems, solved using a standard solver applied to our reduced and strengthened model....

  4. Solving the Liner Shipping Fleet Repositioning Problem with Cargo Flows

    DEFF Research Database (Denmark)

    Tierney, Kevin; Askelsdottir, Björg; Jensen, Rune Møller;

    2015-01-01

    to reposition vessels as cheaply as possible without disrupting cargo flows. The LSFRP is characterized by chains of interacting activities with a multicommodity flow over paths defined by the activities chosen. Despite its industrial importance, the LSFRP has received little attention in the literature. We...... introduce a novel mathematical model and a simulated annealing algorithm for the LSFRP with cargo flows that makes use of a carefully constructed graph; we evaluate these approaches using real-world data from our industrial collaborator. Additionally, we compare the performance of our approach against...

  5. Acoustic Liner for Turbomachinery Applications

    Science.gov (United States)

    Huff, Dennis L.; Sutliff, Daniel L.; Jones, Michael G.; Hebsur, Mohan G.

    2010-01-01

    The purpose of this innovation is to reduce aircraft noise in the communities surrounding airports by significantly attenuating the noise generated by the turbomachinery, and enhancing safety by providing a containment barrier for a blade failure. Acoustic liners are used in today's turbofan engines to reduce noise. The amount of noise reduction from an acoustic liner is a function of the treatment area, the liner design, and the material properties, and limited by the constraints of the nacelle or casement design. It is desirable to increase the effective area of the acoustic treatment to increase noise suppression. Modern turbofan engines use wide-chord rotor blades, which means there is considerable treatment area available over the rotor tip. Turbofan engines require containment over the rotors for protection from blade failure. Traditional methods use a material wrap such as Kevlar integrated with rub strips and sometimes metal layers (sandwiches). It is possible to substitute the soft rub-strip material with an open-cell metallic foam that provides noise-reduction benefits and a sacrificial material in the first layer of the containment system. An open-cell foam was evaluated that behaves like a bulk acoustic liner, serves as a tip rub strip, and can be integrated with a rotor containment system. Foams can be integrated with the fan-containment system to provide sufficient safety margins and increased noise attenuation. The major innovation is the integration of the foam with the containment.

  6. Machine Gun Liner Bond Strength

    Science.gov (United States)

    2007-08-01

    explosive bonding of pure tantalum, several tantalum alloys, and Stellite 25 (an alloy of cobalt, chrome , nickel, and tungsten) in a liner...Difficulties have been experienced in machining an explosively- clad tantalum alloy in an M242 Bushmaster barrel [6].) One disadvantage of Stellite 25 was

  7. Characterization of EPICOR II Prefilter Liner 16

    Energy Technology Data Exchange (ETDEWEB)

    Yesso, J D; Pasupathi, V; Lowry, L

    1982-08-01

    As part of the overall TMI-2 Information and Examination Program, EPICOR II Prefilter Liner 16 was examined to provide information to aid in the development of technology for safely processing highly loaded ion-exchange media. The characterization program included sampling and analyses of the liner contents, including ion-exchange media, liquids and gases, as well as examinations of the liner interior and exterior. This report details the handling of the liner, sampling and analysis of the contents, and the examinations of the liner.

  8. The once & future repository, HKU's Scholars Hub

    OpenAIRE

    Palmer, DT; Castro, P.; Bollini, A; Mennielli, M

    2015-01-01

    The HKU Scholars Hub (the Hub) began service as a traditional institutional repository of The University of Hong Kong (HKU). However this format was not compelling to HKU researchers. Fortunately a subsequent reformation of the HKU statement on university mission and vision infused new life and purpose into the project. Over the next five years, in partnership with the Italian University Consortium, Cineca, the HKU Libraries transformed the Hub from an IR to a Current Research Information ...

  9. Process Analysis in Container Shipping Network Structure Form Change

    Directory of Open Access Journals (Sweden)

    Chen Chao

    2012-03-01

    Full Text Available Being aimed at the influence of ship-size and cargo-demand changes on container shipping networks, to reveal the evolution process of container shipping networks structure form, this paper respectively designed the operation models for two major container shipping networks structure forms: Multi-port-calling network and Hub-and-spoke network, to maximizing the investment efficiency. Based on the above models, a comprehensively integrated operation model of container shipping networks is built and the evolution process of container shipping networks structure form with changing of both ship-size and cargo demands is analyzed. Finally, through a case study, results show that the comprehensive integrated operation model is very effective in the analysis of evolution process of container shipping networks structure forms.

  10. On GitHub's Programming Languages

    OpenAIRE

    2016-01-01

    GitHub is the most widely used social, distributed version control system. It has around 10 million registered users and hosts over 16 million public repositories. Its user base is also very active as GitHub ranks in the top 100 Alexa most popular websites. In this study, we collect GitHub's state in its entirety. Doing so, allows us to study new aspects of the ecosystem. Although GitHub is the home to millions of users and repositories, the analysis of users' activity time-series reveals tha...

  11. Ship construction

    National Research Council Canada - National Science Library

    Eyres, D.J; Bruce, G.J

    2012-01-01

    .... "Acting as both a professional reference on current approaches in shipyard practice and a comprehensive introduction for students in any marine discipline, Ship Construction covers the complete...

  12. Shipping Fairways

    Data.gov (United States)

    Department of Homeland Security — Various shipping zones delineate activities and regulations for marine vessel traffic. Traffic lanes define specific traffic flow, while traffic separation zones...

  13. Ship Hydrodynamics

    Science.gov (United States)

    Lafrance, Pierre

    1978-01-01

    Explores in a non-mathematical treatment some of the hydrodynamical phenomena and forces that affect the operation of ships, especially at high speeds. Discusses the major components of ship resistance such as the different types of drags and ways to reduce them and how to apply those principles for the hovercraft. (GA)

  14. Virtual Campus Hub technical evaluation report

    DEFF Research Database (Denmark)

    Vercoulen, Frank; Badger, Merete; Monaco, Lucio;

    This report describes and discusses the technical achievements of the Virtual Campus Hub project and formulates a brief agenda for the future.......This report describes and discusses the technical achievements of the Virtual Campus Hub project and formulates a brief agenda for the future....

  15. Logistics hubs: an integration of transport infrastructure

    CSIR Research Space (South Africa)

    Botha, M

    2008-07-01

    Full Text Available Logistics hubs are very well established internationally and many examples exist where these have been successfully built and implemented. This success have lead to the proliferation of such hubs and in South Africa there are many "decision makers...

  16. Hub discovery in partial correlation graphical models

    CERN Document Server

    Hero, Alfred

    2011-01-01

    This paper treats the problem of screening a p-variate sample for strongly and multiply connected vertices in the partial correlation graph associated with the the partial correlation matrix of the sample. This problem, called hub screening, is important in many applications ranging from network security to computational biology to finance to social networks. In the area of network security, a node that becomes a hub of high correlation with neighboring nodes might signal anomalous activity such as a coordinated flooding attack. In the area of computational biology the set of hubs of a gene expression correlation graph can serve as potential targets for drug treatment to block a pathway or modulate host response. In the area of finance a hub might indicate a vulnerable financial instrument or sector whose collapse might have major repercussions on the market. In the area of social networks a hub of observed interactions between criminal suspects could be an influential ringleader. The techniques and theory pr...

  17. Magnetized Target Fusion Driven by Plasma Liners

    Science.gov (United States)

    Thio, Y. C. Francis; Cassibry, Jason; Eskridge, Richard; Kirkpatrick, Ronald C.; Knapp, Charles E.; Lee, Michael; Martin, Adam; Smith, James; Wu, S. T.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    For practical applications of magnetized target fusion, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Quasi-spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a quasi-spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). Theoretical analysis and computer modeling of the concept are presented. It is shown that, with the appropriate choice of the flow parameters in the liner and the target, the impact between the liner and the target plasma can be made to be shockless in the liner or to generate at most a very weak shock in the liner. Additional information is contained in the original extended abstract.

  18. Dynamic hubs show competitive and static hubs non-competitive regulation of their interaction partners.

    Directory of Open Access Journals (Sweden)

    Apurv Goel

    Full Text Available Date hub proteins have 1 or 2 interaction interfaces but many interaction partners. This raises the question of whether all partner proteins compete for the interaction interface of the hub or if the cell carefully regulates aspects of this process? Here, we have used real-time rendering of protein interaction networks to analyse the interactions of all the 1 or 2 interface hubs of Saccharomyces cerevisiae during the cell cycle. By integrating previously determined structural and gene expression data, and visually hiding the nodes (proteins and their edges (interactions during their troughs of expression, we predict when interactions of hubs and their partners are likely to exist. This revealed that 20 out of all 36 one- or two- interface hubs in the yeast interactome fell within two main groups. The first was dynamic hubs with static partners, which can be considered as 'competitive hubs'. Their interaction partners will compete for the interaction interface of the hub and the success of any interaction will be dictated by the kinetics of interaction (abundance and affinity and subcellular localisation. The second was static hubs with dynamic partners, which we term 'non-competitive hubs'. Regulatory mechanisms are finely tuned to lessen the presence and/or effects of competition between the interaction partners of the hub. It is possible that these regulatory processes may also be used by the cell for the regulation of other, non-cell cycle processes.

  19. Elastomer liners for geothermal tubulars Y267 EPDM Liner Program:

    Energy Technology Data Exchange (ETDEWEB)

    Hirasuna, A.R.; Davis, D.L.; Flickinger, J.E.; Stephens, C.A.

    1987-12-01

    The elastomer, Y267 EPDM, has been identified as a hydrothermally stable material which can operate at temperatures in excess of 320/sup 0/C. The goal of the Y267 Liner Program was to demonstrate the feasibility of using this material as a liner for mild steel tubulars to prevent or mitigate corrosion. If successful, the usage of EPDM lined pipe by the geothermal community may have a significant impact on operating costs and serve as a viable alternative to the use of alloyed tubulars. Tooling procedures were developed under this program to mold a 0.64 cm (0.25'') thick Y267 EPDM liner into a tubular test section 61 cm (2') in length and 19.1 cm (7.5'') in diameter (ID). A successful effort was made to identify a potential coupling agent to be used to bond the elastomer to the steel tubular wall. This agent was found to withstand the processing conditions associated with curing the elastomer at 288/sup 0/C and to retain a significant level of adhesive strength following hydrothermal testing in a synthetic brine at 260/sup 0/C for a period of 166 hours. Bonding tests were conducted on specimens of mild carbon steel and several alloys including Hastelloy C-276. An objective of the program was to field test the lined section of pipe mentioned above at a geothermal facility in the Imperial Valley. Though a test was conducted, problems encountered during the lining operation precluded an encouraging outcome. The results of the field demonstration were inconclusive. 6 refs., 13 figs., 13 tabs

  20. Test Ship

    Data.gov (United States)

    Federal Laboratory Consortium — The U. S. Navy dedicated the decommissioned Spruance Class destroyer ex-PAUL F. FOSTER (EDD 964), Test Ship, primarily for at sea demonstration of short range weapon...

  1. Arctic Shipping

    DEFF Research Database (Denmark)

    Hansen, Carsten Ørts; Grønsedt, Peter; Lindstrøm Graversen, Christian

    maritime industries (including shipping, offshore energy, ports, and maritime service and equipment suppliers) as well as addresses topics that cut across maritime industries (regulation and competitiveness). The topics and narrower research questions addressed in the initiative were developed in close...

  2. Routing and Scheduling in Tramp Shipping - Integrating Bunker Optimization

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte; Lusby, Richard Martin; Larsen, Jesper

    A tramp ship operator typically has some contracted cargoes that must be carried and seeks to maximize proFIt by carrying optional cargoes. Hence, tramp ships operate much like taxies following available cargoes and not according to a fixed route network and itinerary as liner ships. Marine fuel...... is referred to as bunker and bunker costs constitute a significant part of the daily operating costs. There can be great variations in bunker prices across bunker ports so it is important to carefully plan bunkering for each ship. As ships operate 24 hours a day, they must refuel during operations. Therefore...... of which cargoes to carry and on which ships is affected by the bunker integration and by changes in the bunker prices....

  3. Routing and Scheduling in Tramp Shipping - Integrating Bunker Optimization

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte; Lusby, Richard Martin; Larsen, Jesper

    A tramp ship operator typically has some contracted cargoes that must be carried and seeks to maximize pro_t by carrying optional cargoes. Hence, tramp ships operate much like taxies following available cargoes and not according to a _xed route network and itinerary as liner ships. Marine fuel...... is referred to as bunker fuel or simply bunker and bunker costs constitute a signi_cant part of the daily operating costs. There can be great variations in bunker prices across bunker ports so it is important to carefully plan bunkering for each ship. As ships operate 24 hours a day, they must refuel during......?ts and that the decision of which cargoes to carry and on which ships is affected by the bunker integration and by changes in the bunker prices....

  4. Repairing liner of the reactor; Reparacion del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

  5. Innovation Hub How-To

    DEFF Research Database (Denmark)

    Berger, Andreas; Brem, Alexander

    2016-01-01

    Firms around the world are eager to replicate the successes of enterprises that have established innovation labs in California's Silicon Valley. An analysis of four leading US companies that have set up idea incubators in the Valley—Xerox, Apple, Google, and Cisco—point to eight factors for succe...... disruptive over incremental innovation, and being patient. Regardless of where an innovation hub is established, the key to success lies in hiring creative, intrinsically motivated staff and then giving them the freedom to do what they do best.......Firms around the world are eager to replicate the successes of enterprises that have established innovation labs in California's Silicon Valley. An analysis of four leading US companies that have set up idea incubators in the Valley—Xerox, Apple, Google, and Cisco—point to eight factors for success...... in establishing an innovative environment: carefully considering the decision to set up such a center, hiring the right people, designing a framework for effective output, creating a buffer from bureaucratic distractions, securing a leader to champion the effort, focusing on business outcomes, fostering...

  6. HYDRAULIC CONDUCTIVITY OF THREE GEOSYNTHETIC CLAY LINERS

    Science.gov (United States)

    The hydraulic conductivity of three 2.9 m2 (32 sq ft) geosynthetic clay liners (GCLs) was measured. Tests were performed on individual sheets of the GCLs, on overlapped pieces of GCLs, and on composite liners consisting of a punctured geomembrane overlying a GCL. Hyd...

  7. Water movement through an experimental soil liner

    Science.gov (United States)

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.R.; Herzog, B.L.

    1991-01-01

    A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (???1 x 10-7 cm s-1). The 8 x 15 x 0.9m liner was constructed in 15 cm compacted lifts using a 20,037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water break through at the base of the liner occurs. Estimated saturated hydraulic conductivities were 2.5 x 10-9, 4.0 x 10-8, and 5.0 x 10-8 cm s-1 based on measurements of water infiltration into the liner by large- and small-ring infiltrometers and a water balance analysis, respectively. Also investigated in this research was the variability of the liner's hydraulic properties and estimates of the transit times for water and tracers. Small variances exhibited by small-ring flux data suggested that the liner was homogeneous with respect to infiltration fluxes. The predictions of water and tracer breakthrough at the base of the liner ranged from 2.4-12.6 y, depending on the method of calculation and assumptions made. The liner appeared to be saturated to a depth between 18 and 33 cm at the end of the first year of monitoring. Transit time calculations cannot be verified yet, since breakthrough has not occurred. The work conducted so far indicates that compacted soil barriers can be constructed to meet the saturated hydraulic conductivity requirement established by the U.S. EPA.A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (??? 1 ?? 10-7 cm s-1). The 8 ?? 15 ?? 0.9 m liner was constructed in 15 cm compacted lifts using a 20.037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water

  8. Stabilized Liner Compressor: The Return of Linus

    Science.gov (United States)

    Turchi, Peter; Frese, Sherry; Frese, Michael; Mielke, Charles; Hinrichs, Mark; Nguyen, Doan

    2015-11-01

    To access the lower cost regime of magneto-inertial fusion at megagauss magnetic field-levels requires the use of dynamic conductors in the form of imploding cylindrical shells, aka, liners. Such liner implosions can compress magnetic flux and plasma to attain fusion conditions, but are subject to Rayleigh-Taylor instabilities, both in the launch and recovery of the liner material and in the final few diameters of implosion. These instabilities were overcome in the Linus program at the Naval Research Laboratory, c. 1979, providing the experimentally-demonstrated basis for repetitive operation and leading to an economical reactor concept at low fusion gain. The recent ARPA-E program for low-cost fusion technology has revived interest in this approach. We shall discuss progress in modeling and design of a Stabilized Liner Compressor (SLC) that extends the earlier work to higher pressures and liner speeds appropriate to potential plasma targets. Sponsored by ARPA-E ALPHA Program.

  9. Zoning Districts - Volusia County HUB Zones

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Historically Underutilized Business (HUB) Zones in Volusia County. Go to http://www.sba.gov/hubzone or contact the Department of Economic Development (386) 248-8048...

  10. Motor coordination: a local hub for coordination.

    Science.gov (United States)

    Calabrese, Ronald L

    2014-03-31

    A local interneuron of a crayfish central pattern generator serves as a hub that integrates ascending and descending coordinating information and passes it on to a local oscillatory microcircuit to coordinate a series of segmental appendages known as swimmerets.

  11. Thermoplastic liners for carbon steel pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Mehdi, Mauyed S.; AlDossary, Abdullah K. [Saudi Aramco, Dhahran (Saudi Arabia)

    2009-12-19

    Materials selection for pipe and fittings used to convey corrosive fluids has often been a challenge. Traditionally, exotic Corrosion Resistant Alloys (CRA) have been used in corrosive environments despite their high cost. Plastic lined carbon steel piping offers a cost effective alternative to the use of CRAs by eliminating corrosion, significantly reducing the use of toxic chemicals and the heavy metal usually present in CRAs. Thermoplastic Liners offer the combination of corrosion resistance and mechanical strength, which are unachievable with singular materials. Under pressure conditions, the liner is fully supported by the metalwork, while under vacuum conditions, the liner must be thick enough along with venting system to withstand the collapsing forces created by the negative pressure. Plastic liners have been used successfully to line and protect metallic pipelines for many years and have become an indispensable requirement of the oil and gas industry particularly with water injection and hydrocarbon services. In the case of internally corroded pipes, the use of thermoplastic liners for rehabilitation is an option to extend the lifetime of companies' assets, reduce maintenance cost and increase intervals between T and Is. For new construction, plastic liners in carbon steel pipes can compete technically and economically with pipelines of CRA materials and other corrosion inhibition systems. This paper describes various design features, installations of thermoplastic liners in comparison to other corrosion inhibition methods. (author)

  12. Contextual Hub Analysis Tool (CHAT): A Cytoscape app for identifying contextually relevant hubs in biological networks

    Science.gov (United States)

    Wiencko, Heather L.; Bernal-Llinares, Manuel; Bryan, Kenneth; Lynn, David J.

    2016-01-01

    Highly connected nodes (hubs) in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT), which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed) than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest. Availability: CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store ( http://apps.cytoscape.org/apps/chat). PMID:27853512

  13. Contextual Hub Analysis Tool (CHAT): A Cytoscape app for identifying contextually relevant hubs in biological networks.

    Science.gov (United States)

    Muetze, Tanja; Goenawan, Ivan H; Wiencko, Heather L; Bernal-Llinares, Manuel; Bryan, Kenneth; Lynn, David J

    2016-01-01

    Highly connected nodes (hubs) in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT), which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed) than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest.

  14. Collaborative Data Analytics with DataHub.

    Science.gov (United States)

    Bhardwaj, Anant; Karger, David; Subramanyam, Harihar; Deshpande, Amol; Madden, Sam; Wu, Eugene; Elmore, Aaron; Parameswaran, Aditya; Zhang, Rebecca

    2015-08-01

    While there have been many solutions proposed for storing and analyzing large volumes of data, all of these solutions have limited support for collaborative data analytics, especially given the many individuals and teams are simultaneously analyzing, modifying and exchanging datasets, employing a number of heterogeneous tools or languages for data analysis, and writing scripts to clean, preprocess, or query data. We demonstrate DataHub, a unified platform with the ability to load, store, query, collaboratively analyze, interactively visualize, interface with external applications, and share datasets. We will demonstrate the following aspects of the DataHub platform: (a) flexible data storage, sharing, and native versioning capabilities: multiple conference attendees can concurrently update the database and browse the different versions and inspect conflicts; (b) an app ecosystem that hosts apps for various data-processing activities: conference attendees will be able to effortlessly ingest, query, and visualize data using our existing apps; (c) thrift-based data serialization permits data analysis in any combination of 20+ languages, with DataHub as the common data store: conference attendees will be able to analyze datasets in R, Python, and Matlab, while the inputs and the results are still stored in DataHub. In particular, conference attendees will be able to use the DataHub notebook - an IPython-based notebook for analyzing data and storing the results of data analysis.

  15. Supervised hub-detection for brain connectivity

    Science.gov (United States)

    Kasenburg, Niklas; Liptrot, Matthew; Reislev, Nina Linde; Garde, Ellen; Nielsen, Mads; Feragen, Aasa

    2016-03-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied, but can smooth discriminative signals in the population, degrading predictive performance. We present a novel hub-detection optimized for supervised learning that both clusters network nodes based on population level variation in connectivity and also takes the learning problem into account. The found hubs are a low-dimensional representation of the network and are chosen based on predictive performance as features for a linear regression. We apply our method to the problem of finding age-related changes in structural connectivity. We compare our supervised hub-detection (SHD) to an unsupervised hub-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any network regression problem. Further development of the presented algorithm will be the extension to other predictive models such as classification or non-linear regression.

  16. Open Cell Metal Foams for Beam Liners?

    CERN Document Server

    Croce, R P; Stabile, A

    2013-01-01

    The possible use of open-cell metal foams for particle accelerator beam liners is considered. Available materials and modeling tools are reviewed, potential pros and cons are pointed out, and a study program is outlined.

  17. Landfill liners from dam reservoir sediments

    Directory of Open Access Journals (Sweden)

    Koś Karolina

    2016-03-01

    Full Text Available Landfill liners from dam reservoir sediments. Every municipal solid waste landfill has to be properly secured to protect the natural environment from possible leachate. Most often an artificial sealing is used, which is based on a soil liner from cohesive soils (clays, silts. Usability evaluation of bottom sediments from Rzeszowski Reservoir for building these liners was presented in the paper. Sediments from dam reservoirs, gathered as a result of the siltation process, can be a valuable material for earthworks purposes. Determination of their possible ways of usage is important, especially before the planned dredging, because thanks to that this material will not be put on a heap. Based on the analysis of the geotechnical parameters of these sediments it was stated that this material can be preliminary allowed for using in liners.

  18. Adaptive Liners for Broadband Noise Reduction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will combine the advantages of adaptive materials with the simplistic passive design of state-of-the-art acoustic liners to provide the ability to tune...

  19. Ship Design

    Science.gov (United States)

    1982-01-01

    Guided missile cruiser equipped with advanced Aegis fleet defense system which automatically tracks hundreds of attacking aircraft or missiles, then fires and guides the ship's own weapons in response. Designed by Ingalls Shipbuilding for the US Navy, the U.S.S. Ticonderoga is the first of four CG-47 cruisers to be constructed. NASTRAN program was used previously in another Navy/Ingalls project involving design and construction of four DDG-993 Kidd Class guided missile destroyers.

  20. Strategic Corporate Social Responsibility in the Container Shipping Industry: A Case Study of the Triple E as part of Maersk's Sustainability Strategy

    OpenAIRE

    Mauricio Andrés Latapí Agudelo 1986

    2017-01-01

    The oversupply within the Container Shipping Industry in combination with a global trade slowdown of the last decade has set an unprecedented financial pressure on Container Shipping Liners over the world. This expressed itself in the record low shipping rates in 2016 for the Asia-Europe route and ultimately the bankruptcy of Hanjin Shipping in August 2016. Given this context, the present study analyses the relevance of Strategic Corporate Social Responsibility (SCSR) to improve the industry´...

  1. Code Verification of Magnetized Cylindrical Liner Implosions

    Science.gov (United States)

    Hess, Mark; Weis, Matthew; Martin, Matthew; Sefkow, Adam; Nakhleh, Charles; Lau, Y. Y.

    2012-10-01

    We investigate the physics of magnetized cylindrical liner implosions with existing MHD codes to verify code accuracy, as well as to understand parametric behavior on figures-of-merit, e.g. radial liner velocity, for designing experiments. In our problem, we assume that there exists a 1-D metallic cylindrical liner with an initial axial magnetic seed field imposed in the system. The liner radially implodes due to a specified drive current while the effects of liner pressure and magnetic seed field compression oppose the implosion. This problem is of importance for future magnetized liner fusion experiments, e.g. MagLIF [1].[4pt]Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. [4pt] [1] S.A. Slutz et al, Phys. Plasmas 17, 056303 (2010).

  2. Hub Status and Indexation of Container Ports

    Directory of Open Access Journals (Sweden)

    Yong-An Park

    2015-06-01

    This study develops two sub-indexes of port classification and capacity, and combines cases of these two sub-indexes into various types in order to find a proper port hub index. The paper demonstrates how different types of port hub index are useful measurements for evaluating outputs and inputs of container ports. In a case analysis we show that the indexes of period variables and lagged variables have more explanatory power with regard to changes of port throughputs and high correlation with inputs.

  3. Consequence analysis of a liner breach due to steam under the liner

    Energy Technology Data Exchange (ETDEWEB)

    HIMES, D.A.

    1999-06-01

    Radiological and toxicological consequences are estimated for a steam release from tank C-106 associated with a breach of the tank liner due to formation of steam under the liner after dry-out of the sludge layer in the tank. The consequences are shown to be well below the most restrictive risk guidelines.

  4. Predicting a Containership's Arrival Punctuality in Liner Operations by Using a Fuzzy Rule-Based Bayesian Network (FRBBN

    Directory of Open Access Journals (Sweden)

    Nurul Haqimin Mohd Salleh

    2017-07-01

    Full Text Available One of the biggest concerns in liner operations is punctuality of containerships. Managing the time factor has become a crucial issue in today's liner shipping operations. A statistic in 2015 showed that the overall punctuality for containerships only reached an on-time performance of 73%. However, vessel punctuality is affected by many factors such as the port and vessel conditions and knock-on effects of delays. As a result, this paper develops a model for analyzing and predicting the arrival punctuality of a liner vessel at ports of call under uncertain environments by using a hybrid decision-making technique, the Fuzzy Rule-Based Bayesian Network (FRBBN. In order to ensure the practicability of the model, two container vessels have been tested by using the proposed model. The results have shown that the differences between prediction values and real arrival times are only 4.2% and 6.6%, which can be considered as reasonable. This model is capable of helping liner shipping operators (LSOs to predict the arrival punctuality of their vessel at a particular port of call.

  5. Exploring hubness in Regional Trade Agreements

    NARCIS (Netherlands)

    Vaal, A. de

    2016-01-01

    In the plethora of Regional Trade Agreements (RTAs) some countries take in a more central position than others in the sense that some countries are much more engaged with other countries through RTAs. Furthermore, the position of some countries is that of a hub: they have (many) trade

  6. Optimising steel hub location in Thailand

    Directory of Open Access Journals (Sweden)

    Sakaradhorn Boontaveeyuwat

    2012-11-01

    Full Text Available The optimal location of a steel hub in Thailand was analysed by applying aspecific research methodology designed to evaluate locations near the seaports. The growth of Thailand’s steel industry has become a centre of attention in the last decade, resulting in substantial efforts to form a distribution service centre to minimise the logistic costs associated with handling large steel flows in the future. The main analysis of the steel hublocation focused on areas situated near Laem Cha Bang, Map Ta Phut and Prachuab ports since these top three ports are considered important in terms of their steel throughput in Thailand. The transport costs associated with the shipment and inland transport together with port tariffs were calculated for the proposed scenarios of steel hub establishment andthese were compared with the existing situation without steel hub. The findings showed that a steel hub located near Laem Cha Bang port was the optimal option involving a saving of 9.4% on the total system costs incurred under the existing situation.

  7. A State Cyber Hub Operations Framework

    Science.gov (United States)

    2016-06-01

    level cyber operations from state information technology (IT) and network infrastructure to hospitals , commercial banking, and manufacturing the...tools - TTPs necessary to operate and maintain Authoritative Data Repository for operational related artifacts . - Monitor and report on operations...development of Data Repository structures to enable storage of Cyber Hub related artifacts . - Provides Technical input to Business Case Analyses (BCAs

  8. Constructing Hongqiao Hub and Serving Regional Economy:Planning and Operation of Hongqiao Comprehensive Transportation Hub

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Taking Hongqiao Integrated Transportation Hub Project as a case, this paper introduces its origin, orientation, development programming, planning and design, road planning, information system planning, air-rail integrated transportation planning, disaster prevention planning, and so on.

  9. Over-heated Investment in Aluminum Hub Industry

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Aluminum hub is one of typical products with the comparative advantages.China’s aluminum hub industry is very competitive.In recent years,the value of export for the aluminum hub soared,increasing from USD130 millions in 1999 up to nearly USD1 billion in 2004.The main exporter are Wanfeng Auto Holding Group,Shanghai Fervent Alloy Wheel MFG Co.,Ltd.,Nanhai Zhongnan Aluminum Co., Ltd.,Taian Huatai Aluminum Hub Co.,Ltd.

  10. A Survey on the Ship Loading Problem

    DEFF Research Database (Denmark)

    Iris, Cagatay; Pacino, Dario

    2015-01-01

    Recent statistics show that large container terminals can process more than 30 million containers a year, and are constantly in search for the better ways to optimize processing time, deliver high quality and profitable services. Some of the terminal decisions are, however, dependent on externali......Recent statistics show that large container terminals can process more than 30 million containers a year, and are constantly in search for the better ways to optimize processing time, deliver high quality and profitable services. Some of the terminal decisions are, however, dependent...... on externalities. One of those is the ship loading process. Based on the stowage plan received by liner shippers, terminal operators plan the execution of load and discharge operations. In this paper we present a literature review for the Ship Loading Problem, where stowage and loading sequencing and scheduling...

  11. Encoding the Shipping Crisis

    Institute of Scientific and Technical Information of China (English)

    Xue Lina; Lin Lin; Wang Siyuan

    2009-01-01

    @@ According to the statistics from Frech shipping advisory bod-ies,till December 21,2008,165 container ships were idle,leav-ing the fees,such as anchorage fees,ship maintaining fee,crev resettlement fee and repaying loans for ship-buying,an-noying the ship-owners.

  12. Shipping Industry Structure

    NARCIS (Netherlands)

    Wijnolst, N.; Waals, F.

    1999-01-01

    Understanding Shipping Management requires a thorough understanding of the Shipping Industry Structure. This book provides this knowledge base and should be seen in conjunction with two other books: Shipping and Design Innovation in Shipping. Shipping Industry Structure was intended as the first par

  13. Shipping Industry Structure

    NARCIS (Netherlands)

    Wijnolst, N.; Waals, F.

    1999-01-01

    Understanding Shipping Management requires a thorough understanding of the Shipping Industry Structure. This book provides this knowledge base and should be seen in conjunction with two other books: Shipping and Design Innovation in Shipping. Shipping Industry Structure was intended as the first par

  14. Shipping Industry Structure

    NARCIS (Netherlands)

    Wijnolst, N.; Waals, F.

    1999-01-01

    Understanding Shipping Management requires a thorough understanding of the Shipping Industry Structure. This book provides this knowledge base and should be seen in conjunction with two other books: Shipping and Design Innovation in Shipping. Shipping Industry Structure was intended as the first

  15. Southwest Regional Climate Hub and California Subsidiary Hub assessment of climate change vulnerability and adaptation and mitigation strategies

    Science.gov (United States)

    Emile Elias; Caiti Steele; Kris Havstad; Kerri Steenwerth; Jeanne Chambers; Helena Deswood; Amber Kerr; Albert Rango; Mark Schwartz; Peter Stine; Rachel Steele

    2015-01-01

    This report is a joint effort of the Southwest Regional Climate Hub and the California Subsidiary Hub (Sub Hub). The Southwest Regional Climate Hub covers Arizona, California, Hawai‘i and the U.S. affiliated Pacific Islands, Nevada, New Mexico, and Utah and contains vast areas of western rangeland, forests, and high-value specialty crops (Figure 1). The California Sub...

  16. Ship?Shore and Ship?Ship Data Transfer

    Science.gov (United States)

    Heikkilä, Martti

    During recent years there has been significant development in several technologies which can contribute to the efficiency and safety of maritime traffic. The most important of these are accurate positioning systems (DGPS), digital data transmission/transponder technology, electronic chart systems (ECDIS), control of ships using electronic passage plans, and ship path prediction. With a widespread implementation of these new techniques, combined with advanced ship-shore and ship-ship data transfer, significant improvements can be achieved in traffic situation awareness both in a VTS and onboard. This paper describes the research carried out at VTT on VTS development, and especially gives an outline of new VTS functions using shipship data transfer.

  17. Extension of Goldstein's circulation function for optimal rotors with hub

    DEFF Research Database (Denmark)

    Okulov, Valery; Sørensen, Jens Nørkær; Shen, Wen Zhong

    2016-01-01

    The aerodynamic interaction or interference between rotor blades and hub body is usually very complicated, but some useful simplifications can be made by considering the hub with an infinite cylinder. Various attempts to find the optimum distribution of circulation by the lifting vortex lines...... method have been previously proposed to describe the blade interaction with the hub modeled by the infinite cylinder. In this case, the ideal distribution of bound circulation on the rotor blades is such that the shed vortex system in the hub-area is a set of helicoidal vortex sheets moving uniformly...... at the nose-area of the semi-infinite hub....

  18. SDU6 Interior Liner Testing & Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, T. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-10-14

    Two liner materials (Marseal® M-3500 and REMA Chemoline® 4CN) proposed for use as a liner inside the Saltstone Disposal Unit 6 (SDU6) were subjected to specific ASTM tests (tensile and lap-shear) after immersion in 50% and 100% simulant solutions for 1000 hours at the Savannah River Ecology Laboratory. Both liner materials exhibited good resistance to the simulant chemistry, at least based on the tests performed and the test duration/conditions imposed. In lap-shear tests, both materials failed in the base material rather than peeling apart, confirming good adhesion. The REMA 4CN bromobutyl elastomer showed superior bonding characteristics and absence of warping or delamination at the conditions tested. The Marseal M-3500 material (PVC/EVA blend with polyester reinforcement) exhibited deformation and debonding in some locations. The cause of the deformation and delamination observed in the Marseal M-3500 material is not fully known, but possibly attributed to thermomechanical stress at immersion temperatures, and the thermoplastic nature of the material. The immersion temperature (68 °C) is slightly greater than the maximum use temperature limit quoted for the Marseal M- 3500 liner (65 °C), though the basis for the service limit is unknown. The testing performed was limited in scope and only for these two liner materials. These tests were primarily performed to screen for severe incompatibility or short-term degradation in Saltstone bleedwater simulants at bounding solution temperatures. Additional testing is recommended to assess long-term performance and the overall service life of the liner.

  19. Lifecycle Verification of Tank Liner Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Anovitz, Lawrence {Larry} M [ORNL; Smith, Barton [ORNL

    2014-03-01

    This report describes a method that was developed for the purpose of assessing the durability of thermoplastic liners used in a Type IV hydrogen storage tank during the tank s expected service life. In the method, a thermoplastic liner specimen is cycled between the maximum and minimum expected working temperatures while it is differentially pressurized with high-pressure hydrogen gas. The number of thermal cycling intervals corresponds to those expected within the tank s design lifetime. At prescribed intervals, hydrogen permeation measurements are done in situ to assess the ability of the liner specimen to maintain its hydrogen barrier properties and to model its permeability over the tank lifetime. Finally, the model is used to assess whether the steady-state leakage rate in the tank could potentially exceed the leakage specification for hydrogen fuel cell passenger vehicles. A durability assessment was performed on a specimen of high-density polyethylene (HDPE) that is in current use as a tank liner. Hydrogen permeation measurements were performed on several additional tank liner polymers as well as novel polymers proposed for use as storage tank liners and hydrogen barrier materials. The following technical barriers from the Fuel Cell Technologies Program MYRDD were addressed by the project: D. Durability of on-board storage systems lifetime of at least 1500 cycles G. Materials of construction vessel containment that is resistant to hydrogen permeation M. Lack of Tank Performance Data and Understanding of Failure Mechanisms And the following technical targets1 for on-board hydrogen storage systems R&D were likewise addressed: Operational cycle life (1/4 tank to full) FY 2017: 1500 cycles; Ultimate: 1500 cycles Environmental health & safety Permeation and leakage: Meets or exceeds applicable standards Loss of useable H2: FY 2017: 0.05 g/h/kg H2; Ultimate: 0.05 g/h/kg H2

  20. Lifecycle Verification of Tank Liner Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Anovitz, Lawrence {Larry} M [ORNL; Smith, Barton [ORNL

    2014-03-01

    This report describes a method that was developed for the purpose of assessing the durability of thermoplastic liners used in a Type IV hydrogen storage tank during the tank s expected service life. In the method, a thermoplastic liner specimen is cycled between the maximum and minimum expected working temperatures while it is differentially pressurized with high-pressure hydrogen gas. The number of thermal cycling intervals corresponds to those expected within the tank s design lifetime. At prescribed intervals, hydrogen permeation measurements are done in situ to assess the ability of the liner specimen to maintain its hydrogen barrier properties and to model its permeability over the tank lifetime. Finally, the model is used to assess whether the steady-state leakage rate in the tank could potentially exceed the leakage specification for hydrogen fuel cell passenger vehicles. A durability assessment was performed on a specimen of high-density polyethylene (HDPE) that is in current use as a tank liner. Hydrogen permeation measurements were performed on several additional tank liner polymers as well as novel polymers proposed for use as storage tank liners and hydrogen barrier materials. The following technical barriers from the Fuel Cell Technologies Program MYRDD were addressed by the project: D. Durability of on-board storage systems lifetime of at least 1500 cycles G. Materials of construction vessel containment that is resistant to hydrogen permeation M. Lack of Tank Performance Data and Understanding of Failure Mechanisms And the following technical targets1 for on-board hydrogen storage systems R&D were likewise addressed: Operational cycle life (1/4 tank to full) FY 2017: 1500 cycles; Ultimate: 1500 cycles Environmental health & safety Permeation and leakage: Meets or exceeds applicable standards Loss of useable H2: FY 2017: 0.05 g/h/kg H2; Ultimate: 0.05 g/h/kg H2

  1. A Branch and Cut algorithm for the container shipping network design problem

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander; Pisinger, David

    2012-01-01

    The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear...

  2. Simultaneous Optimization of Container Ship Sailing Speed and Container Routing with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Røpke, Stefan; Pisinger, David

    We introduce a decision support tool for liner shipping companies to optimally determine the sailing speed and needed fleet for a global network. As a novelty we incorporate cargo routing decisions with tight transit time restrictions on each container such that we get a realistic picture...

  3. Developmental Changes in Brain Network Hub Connectivity in Late Adolescence.

    Science.gov (United States)

    Baker, Simon T E; Lubman, Dan I; Yücel, Murat; Allen, Nicholas B; Whittle, Sarah; Fulcher, Ben D; Zalesky, Andrew; Fornito, Alex

    2015-06-17

    The human brain undergoes substantial development throughout adolescence and into early adulthood. This maturational process is thought to include the refinement of connectivity between putative connectivity hub regions of the brain, which collectively form a dense core that enhances the functional integration of anatomically distributed, and functionally specialized, neural systems. Here, we used longitudinal diffusion magnetic resonance imaging to characterize changes in connectivity between 80 cortical and subcortical anatomical regions over a 2 year period in 31 adolescents between the ages of 15 and 19 years. Connectome-wide analysis indicated that only a small subset of connections showed evidence of statistically significant developmental change over the study period, with 8% and 6% of connections demonstrating decreased and increased structural connectivity, respectively. Nonetheless, these connections linked 93% and 90% of the 80 regions, respectively, pointing to a selective, yet anatomically distributed pattern of developmental changes that involves most of the brain. Hub regions showed a distinct tendency to be highly connected to each other, indicating robust "rich-club" organization. Moreover, connectivity between hubs was disproportionately influenced by development, such that connectivity between subcortical hubs decreased over time, whereas frontal-subcortical and frontal-parietal hub-hub connectivity increased over time. These findings suggest that late adolescence is characterized by selective, yet significant remodeling of hub-hub connectivity, with the topological organization of hubs shifting emphasis from subcortical hubs in favor of an increasingly prominent role for frontal hub regions.

  4. Spatial Economic Hubs and State Power

    Institute of Scientific and Technical Information of China (English)

    Xuan Xingzhang; Huang Jing

    2008-01-01

    The paper seeks to analyze the rise of state power in the light of spatial economic shifts and examines the historical context of China's rise and challenges facing it. In world history, only countries that were spatial economic hubs have been able to enjoy prosperity over centuries. China is not yet such a country, despite its persistent efforts. Nor is China likely to become an economic hub in the foreseeable future. China is under mounting pressure from new economic demands posed by shifts in the geo-economic status of the U.S.. The fact that the global economy thrives along coastlines also causes problems for China, a country with a long coastline and a vast hinterland, creating rifts between northern and southern China, central and local governments, and different provinces. All these factors might well hinder China's development in the future.

  5. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Nonmetallic membrane liner. 193.2187 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank....

  6. Topographic hub maps of the human structural neocortical network.

    Directory of Open Access Journals (Sweden)

    Emil H J Nijhuis

    Full Text Available Hubs within the neocortical structural network determined by graph theoretical analysis play a crucial role in brain function. We mapped neocortical hubs topographically, using a sample population of 63 young adults. Subjects were imaged with high resolution structural and diffusion weighted magnetic resonance imaging techniques. Multiple network configurations were then constructed per subject, using random parcellations to define the nodes and using fibre tractography to determine the connectivity between the nodes. The networks were analysed with graph theoretical measures. Our results give reference maps of hub distribution measured with betweenness centrality and node degree. The loci of the hubs correspond with key areas from known overlapping cognitive networks. Several hubs were asymmetrically organized across hemispheres. Furthermore, females have hubs with higher betweenness centrality and males have hubs with higher node degree. Female networks have higher small-world indices.

  7. Extension of Goldstein's circulation function for optimal rotors with hub

    Science.gov (United States)

    Okulov, V. L.; Sørensen, J. N.; Shen, W. Z.

    2016-09-01

    The aerodynamic interaction or interference between rotor blades and hub body is usually very complicated, but some useful simplifications can be made by considering the hub with an infinite cylinder. Various attempts to find the optimum distribution of circulation by the lifting vortex lines method have been previously proposed to describe the blade interaction with the hub modeled by the infinite cylinder. In this case, the ideal distribution of bound circulation on the rotor blades is such that the shed vortex system in the hub-area is a set of helicoidal vortex sheets moving uniformly as if rigid, exactly as in the case where there is no influence of the streamtube deformations by the central hub-body. In the present investigation, we consider a more specific problem of the rotor-hub interaction where the initial flow streamtubes and the rotor slipstream submitted strong deformations at the nose-area of the semi-infinite hub.

  8. Ranking hubs and authorities using matrix functions

    OpenAIRE

    2012-01-01

    The notions of subgraph centrality and communicability, based on the exponential of the adjacency matrix of the underlying graph, have been effectively used in the analysis of undirected networks. In this paper we propose an extension of these measures to directed networks, and we apply them to the problem of ranking hubs and authorities. The extension is achieved by bipartization, i.e., the directed network is mapped onto a bipartite undirected network with twice as many nodes in order to ob...

  9. Developing Istanbul into a Regional Business Hub

    Science.gov (United States)

    2004-12-01

    beds). Every year Istanbul hosts people from all around the world for international summits, conferences, film and music festivals and sports...Kong, Taiwan, Malaysia , Thailand, and the Philippines are positioning themselves to be logistics hubs. On the other hand, in Eastern Europe; Czech...close to nearby major markets of the world, are only some of Turkey’s many advantages. 2. Istanbul Throughout history , Istanbul has been a city at the

  10. 班轮联营企业系统自组织特性与演化机制%Self- organization Characteristics and Evolution Mechanism of Liner Joint Venture

    Institute of Scientific and Technical Information of China (English)

    陈继红

    2012-01-01

    With the globalization of container liner shipping and container ship maximization, liner enterprises are trending towards joint venture. It greatly enriches the approaches to research liner joint venture shipping by applying self-organization theory to researching container liner shipping joint system. By analyzing the self-organization characteristics of liner joint venture system, can author show that joint venture is a important mechanism to establish cooperation, development and sustainability for liner enter- prises;the synergistic degree acting in controlling parameters are revealed by the angle of system model- ing, and the paper discusses the liner joint venture system and internal evolution mechanism of joint man- agement mode.%伴随着集装箱班轮运输全球化和集装箱船舶大型化,班轮企业走向联营。将自组织理论引入到对集装箱班轮运输联营系统研究中,大大丰富了班轮企业联营运输的研究手段。通过班轮联营系统的自组织特征分析,说明联营模式是班轮企业构建合作发展及可持续经营的重要机制;从系统建模的角度揭示了在班轮联营系统演化过程中各联营企业的协同程度起到控制参量的作用,探讨了班轮联营系统和联营模式演化的内在机理。

  11. Leakage effects on LMFBR cell liners

    Energy Technology Data Exchange (ETDEWEB)

    Stone, C.M.; Gartling, D.K.; Nickell, R.E.

    1978-01-01

    The thermostructural effects of a molten sodium spill onto a Liquid Metal Fast Breeder Reactor (LMFBR) cell liner are investigated utilizing a geometrically simple finite element model. The sodium spill is considered for various flow rate regimes. Because the actual characteristics of a spill are unknown, a parametric analysis was performed with the size of spill and heat transfer coefficient as variables.

  12. Membrane behavior of clay liner materials

    Science.gov (United States)

    Kang, Jong Beom

    Membrane behavior represents the ability of porous media to restrict the migration of solutes, leading to the existence of chemico-osmosis, or the flow of liquid in response to a chemical concentration gradient. Membrane behavior is an important consideration with respect to clay soils with small pores and interactive electric diffuse double layers associated with individual particles, such as bentonite. The results of recent studies indicate the existence of membrane behavior in bentonite-based hydraulic barriers used in waste containment applications. Thus, measurement of the existence and magnitude of membrane behavior in such clay soils is becoming increasingly important. Accordingly, this research focused on evaluating the existence and magnitude of membrane behavior for three clay-based materials that typically are considered for use as liners for waste containment applications, such as landfills. The three clay-based liner materials included a commercially available geosynthetic clay liner (GCL) consisting of sodium bentonite sandwiched between two geotextiles, a compacted natural clay known locally as Nelson Farm Clay, and compacted NFC amended with 5% (dry wt.) of a sodium bentonite. The study also included the development and evaluation of a new flexible-wall cell for clay membrane testing that was used subsequently to measure the membrane behaviors of the three clay liner materials. The consolidation behavior of the GCL under isotropic states of stress also was evaluated as a preliminary step in the determination of the membrane behavior of the GCL under different effective consolidation stresses.

  13. Diagnostics for the plasma liner experiment.

    Science.gov (United States)

    Lynn, A G; Merritt, E; Gilmore, M; Hsu, S C; Witherspoon, F D; Cassibry, J T

    2010-10-01

    The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ∼0.1 Mbar using ∼1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)∼10(16) cm(-3), T(e)≈T(i)∼1 eV at the plasma gun mouth to n(i)>10(19) cm(-3), T(e)≈T(i)∼0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

  14. Conversion of acoustic energy by lossless liners

    Science.gov (United States)

    Moehring, W.; Eversman, W.

    1982-01-01

    The Blokhintzev acoustic energy equation is applied to a two-dimensional duct containing a uniform flow with a finite length lining. It is shown that the difference of the incident and outgoing acoustic energy differs in general from the energy dissipated in the liner, the difference being related to the displacements at the liner's edges. It is shown that in the case of a locally reacting lossless liner for frequencies below the first cut-off frequency and for low Mach number acoustic energy is generated if the flow and the incident sound wave are in the same direction and is absorbed if these two directions are opposite unless special edge conditions are met. Furthermore it is shown under the same conditions that the ratio of the reflection coefficient at finite flow velocity to the reflection coefficient at vanishing velocity is to first order in Mach number independent of the liner characteristics. A numerical calculation confirms these predictions at least for mass-like linear admittance.

  15. Geosynthetic clay liners shrinkage under simulated daily thermal cycles.

    Science.gov (United States)

    Sarabadani, Hamid; Rayhani, Mohammad T

    2014-06-01

    Geosynthetic clay liners are used as part of composite liner systems in municipal solid waste landfills and other applications to restrict the escape of contaminants into the surrounding environment. This is attainable provided that the geosynthetic clay liner panels continuously cover the subsoil. Previous case histories, however, have shown that some geosynthetic clay liner panels are prone to significant shrinkage and separation when an overlying geomembrane is exposed to solar radiation. Experimental models were initiated to evaluate the potential shrinkage of different geosynthetic clay liner products placed over sand and clay subsoils, subjected to simulated daily thermal cycles (60°C for 8 hours and 22°C for 16 hours) modelling field conditions in which the liner is exposed to solar radiation. The variation of geosynthetic clay liner shrinkage was evaluated at specified times by a photogrammetry technique. The manufacturing techniques, the initial moisture content, and the aspect ratio (ratio of length to width) of the geosynthetic clay liner were found to considerably affect the shrinkage of geosynthetic clay liners. The particle size distribution of the subsoil and the associated suction at the geosynthetic clay liner-subsoil interface was also found to have significant effects on the shrinkage of the geosynthetic clay liner.

  16. Green shipping management

    CERN Document Server

    Lun, Y H Venus; Wong, Christina W Y; Cheng, T C E

    2016-01-01

    This book presents theory-driven discussion on the link between implementing green shipping practices (GSP) and shipping firm performance. It examines the shipping industry’s challenge of supporting economic growth while enhancing environmental performance. Consisting of nine chapters, the book covers topics such as the conceptualization of green shipping practices (GSPs), measurement scales for evaluating GSP implementation, greening capability, greening and performance relativity (GPR), green management practice, green shipping network, greening capacity, and greening propensity. In view of the increasing quest for environment protection in the shipping sector, this book provides a good reference for firms to understand and evaluate their capability in carrying out green operations on their shipping activities.

  17. Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment

    Directory of Open Access Journals (Sweden)

    Michalski Jan P.

    2016-04-01

    Full Text Available The paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate. The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the preliminary ship design or in the simulation of pre-investment transportation task studies.

  18. Biaxial wheel/hub test facility. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G.; Grubisic, V. [eds.

    2000-07-01

    The 4{sup th} meeting aims to exchange the experience and knowledge of engineers during several presentations and discussions about new developments required for a reliable, time and cost reducing validation of the wheel/hub assembly. Tremendous development of the wheel performance, described by the ratio of the rated load (kg) versus the wheel weight (kg) had taken place during the last 5000 years. Starting from the ratio of 3 for wooden 2-piece-disc-wheels in Mesopotamia it needed nearly 1000 years to increase the ratio to approx 5 at light-weight spoke wheels for fighting carriages, found in the grave of king Tutenchamon in Egypt. Modern light alloy wheels of commercial vehicles reach values up to 160 kg/kg. Additionally the comlex design of the modern systems for cars and commercial vehicles comprising wheel, brake, hub, bearing, spindle and hub carrier, including different materials and their treatment, fasteners, press-fits, require an appropriate testing procedure. The variable loading conditions, caused by operational wheel forces, brake and torque moments including heating, may result in changing tolerances and press-fits during operation and consequently in different damage mechanisms. This can be simulated in the Biaxial Wheel Test Machine, whereby corresponding load programs are necessary. An overview about all biaxial test machines in usage at the end of 1999 is shown in the introduction. The total number is 17 for cars, 7 for commercial vehicles and 1 for trains. The six presentations of this meeting were consequently concentrated on: (a) recommendations for a standardization of load programs of the German Wheel Committee, (b) the simulation of brake and torque events and (c) the possibility for a numerical stress analyses and fatigue life assessment. (orig./AKF)

  19. Parametric study of propeller boss cap fins for container ships

    Directory of Open Access Journals (Sweden)

    Lim Sang-Seop

    2014-06-01

    Full Text Available The global price of oil, which is both finite and limited in quantity, has been rising steadily because of the increasing requirements for energy in both developing and developed countries. Furthermore, regulations have been strengthened across all industries to address global warming. Many studies of hull resistance, propulsion and operation of ships have been performed to reduce fuel consumption and emissions. This study examined the design parameters of the propeller boss cap fin (PBCF and hub cap for 6,000TEU container ships to improve the propulsion efficiency. The design parameters of PBCF have been selected based on the geometrical shape. Computational fluid dynamics (CFD analysis with a propeller open water (POW test was performed to check the validity of CFD analysis. The design of experiment (DOE case was selected as a full factorial design, and the experiment was analyzed by POW and CFD analysis. Analysis of variance (ANOVA was performed to determine the correlation among design parameters. Four design alternatives of PBCF were selected from the DOE. The shape of a propeller hub cap was selected as a divergent shape, and the divergent angle was determined by the DOE. Four design alternatives of PBCF were attached to the divergent hub cap, and the POW was estimated by CFD. As a result, the divergent hub cap with PBCF has a negative effect on the POW, which is induced by an increase in torque coefficient. A POW test and cavitation test were performed with a divergent hub cap with PBCF to verify the CFD result. The POW test result showed that the open water efficiency was increased approximately 2% with a divergent hub cap compared to a normal cap. The POW test result was similar to the CFD result, and the divergent hub cap with the PBCF models showed lower open water efficiency. This was attributed to an increase in the torque coefficient just like the CFD results. A cavitation test was performed using the 2 models selected. The test

  20. Novel Ship Propulsion System

    Institute of Scientific and Technical Information of China (English)

    JI Yulong; SUN Yuqing; ZHANG Hongpeng; ZHANG Yindong; CHEN Haiquan

    2009-01-01

    As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion (IHP), is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion (DP) ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.

  1. Supervised hub-detection for brain connectivity

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Liptrot, Matthew George; Reislev, Nina Linde

    2016-01-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied......-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any...

  2. The shipping man adventures in ship finance

    CERN Document Server

    McCleery, Matthew

    2013-01-01

    When restless New York City hedge fund manager Robert Fairchild watches the Baltic Dry Cargo Index plunge 97%, registering an all-time high and a 25-year low within the span of just six months, he decides to buy a ship. Immediately fantasizing about naming a vessel after his wife, carrying a string of worry beads and being able to introduce himself as a "shipowner" at his upcoming college reunion, Fairchild immediately embarks on an odyssey into the most exclusive, glamorous and high stakes business in the world. From pirates off the coast of Somalia and on Wall Street to Greek and Norwegian shipping magnates, the education of Robert Fairchild is an expensive one. In the end, he loses his hedge fund, but he gains a life - as a Shipping Man. Part fast paced financial thriller, part ship finance text book, The Shipping Man is 310 pages of required reading for anyone with an interest in capital formation for shipping.

  3. An Introduction to Version Control Using GitHub Desktop

    Directory of Open Access Journals (Sweden)

    Daniel van Strien

    2016-06-01

    Full Text Available In this lesson you will be introduced to the basics of version control, understand why it is useful and implement basic version control for a plain text document using GitHub Desktop. By the end of this lesson you should understand: * what version control is and why it can be useful * the differences between Git and GitHub * how to implement version control using ‘GitHub Desktop,’ a Graphical User Interface for GitHub * be aware of other resources that will help you implement version control in your academic writing

  4. An Introduction to Version Control Using GitHub Desktop

    OpenAIRE

    Daniel van Strien

    2016-01-01

    In this lesson you will be introduced to the basics of version control, understand why it is useful and implement basic version control for a plain text document using GitHub Desktop. By the end of this lesson you should understand: * what version control is and why it can be useful * the differences between Git and GitHub * how to implement version control using ‘GitHub Desktop,’ a Graphical User Interface for GitHub * be aware of other resources that will help you imple...

  5. Development of 1D Liner Compression Code for IDL

    Science.gov (United States)

    Shimazu, Akihisa; Slough, John; Pancotti, Anthony

    2015-11-01

    A 1D liner compression code is developed to model liner implosion dynamics in the Inductively Driven Liner Experiment (IDL) where FRC plasmoid is compressed via inductively-driven metal liners. The driver circuit, magnetic field, joule heating, and liner dynamics calculations are performed at each time step in sequence to couple these effects in the code. To obtain more realistic magnetic field results for a given drive coil geometry, 2D and 3D effects are incorporated into the 1D field calculation through use of correction factor table lookup approach. Commercial low-frequency electromagnetic fields solver, ANSYS Maxwell 3D, is used to solve the magnetic field profile for static liner condition at various liner radius in order to derive correction factors for the 1D field calculation in the code. The liner dynamics results from the code is verified to be in good agreement with the results from commercial explicit dynamics solver, ANSYS Explicit Dynamics, and previous liner experiment. The developed code is used to optimize the capacitor bank and driver coil design for better energy transfer and coupling. FRC gain calculations are also performed using the liner compression data from the code for the conceptual design of the reactor sized system for fusion energy gains.

  6. Broadband Liner Optimization for the Source Diagnostic Test Fan

    Science.gov (United States)

    Nark, Douglas M.; Jones, Michael G.

    2012-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

  7. CAPITAL AND OPERATIONAL CONCENTRATION IN THE CONTAINER SHIPPING

    Directory of Open Access Journals (Sweden)

    Jerzy Kujawa

    2016-12-01

    Full Text Available This paper deals with an analysis of the processes of concentration in the liner, con-tainer shipping. In the first part it focuses on the capital concentration as a result of organic growth and/or consolidation among container shipping operators (whether mergers or acquisitions - M&A. The second part of this article focuses on the operational concentra-tion of container fleets in a form of chartering vessels from non-operator owners and formation of the global container alliances between “big players”. The last part of this article focuses on threats connected with growing concentration of container fleet and market power in this sector of shipping.

  8. Explosively Bonded Gun Tube Liner Development

    Science.gov (United States)

    2015-04-01

    level (MRL 10) measures aspects of lean practices and continuous improvement for systems in production. C.1 MRL 1: Basic Manufacturing Implications...the art is assessed through the use of Technology and Manufacturing Readiness Levels. 15. SUBJECT TERMS Ta alloys, gun-tube liners, explosive...bonding, firing tests, Technology Readiness Level, Manufacturing Readiness Level 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18

  9. Progress in plasma liner modeling for MIF

    Science.gov (United States)

    Loverich, John; Hakim, Ammar; Zhou, Sean

    2009-11-01

    Magnetic confinement fusion and inertial confinement fusion represent the two extremes in terms of density and confinement time in fusion energy research. Both approaches have been studied extensively through the decades pushing technology to the limits. An alternative fusion approach exists between these regimes called magnetized target fusion. In magnetized target fusion longer confinement times are achieved than in ICF through the use of strong magnetic fields, the long confinement time reduces the required plasma density to reach ignition--the approach has advantages over MFE in that it is much more compact and higher density. This work explores computationally a form of magnetized target implosion using a plasma liner. This concept is to be compared with solid liner implosion approach which may not be commercially viable as a reactor due to the ``standoff'' problem, portions of the device are destroyed with each target implosion. We present simulation results of plasma liner formation, jet merging, and plasma jet magnetized target interaction using a fluid plasma code (TxFluids) developed at Tech-X corporation.

  10. Line, LINER, linest - from micro-AGN to ultra-luminous LINERs. One and the same?

    CERN Document Server

    Winkler, Hartmut

    2014-01-01

    This paper compares the optical spectra of a wide range of galaxies categorised as members of the Low Ionisation Nuclear Emission Region (LINER) class of active galactic nuclei (AGN). LINERs are defined by emission spectra with relatively faint high ionisation lines (compared to other AGN classes). The gas emission luminosity ranges from the weak flux emanating from some nearby galactic nuclei all the way to extremely luminous radio galaxies, where the line emission can completely dominate the host galaxy starlight component. In this study I analyse the Sloane Digital Sky Survey optical spectra of 15 LINERS identified in the course of the preparation of the new edition of the ZORROASTER AGN catalogue, spanning the largest possible luminosity range. I compare relative emission line strengths, focusing on uncommonly analysed ratios such as those involving [N I], line widths, profiles and even the spectral features of the host galaxy stellar continuum. The study identifies possible luminosity dependent trends in...

  11. Diagnostic for the plasma liner experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gilmore, M.; Merritt, E.; Lynn, A.G. [University of New Mexico, Albuquerque NM (United States); Bauer, B.S.; Fuelling, S.; Siemen, R.E. [University of Nevada, Reno NV (United States); Hsu, S.C. [Los Alamos National Laboratory, Los Alamos NM (United States); Witherspoon, F.D.; Brockington, S.; Case, A.; Messer, S.J. [HyperV Tecnologies Corp, Chantilly VA (United States); Cassibry, J.T. [University of Alabama, Huntsville AL (United States)

    2011-07-01

    Magneto-Inertial Fusion (MIF) includes a class of fusion energy concepts that seek to relax the required implosion times of inertial fusion to microseconds rather than nanoseconds by utilizing magnetized targets. The Plasma Liner Experiment (PLX) at Los Alamos National Laboratory will explore and demonstrate the feasibility of forming imploding spherical 'plasma liners' that can reach peak pressures {approx} 0.1 Mbar upon stagnation. The liners will be formed via merging of 30 - 60 dense, high Mach number plasma jets (M {approx} 10-35, v {approx} 50-70 km/s, jet radius {approx} 5 cm) in spherically convergent geometry. This is a staged, exploratory project where scientific issues will be studied first at modest stored energies ({approx} 300 kJ) before attempting to reach MIF-relevant pressures (requiring {approx} 1.5 MJ). Key physics issues include peak parameters (n, T, radius) at stagnation, dynamics of the merging jet liner formation (e.g. lateral shocks, instabilities), and spherical symmetry of the liner. Plasmas will be high-Z species (e.g. Ar, Xe), unmagnetized, and are expected to have densities {approx} 10{sup 22} m{sup -3} and low temperature, Te {approx} Ti {approx} a few eV, when initially exiting the plasma guns where the jets are formed. Density and temperature will first decrease slightly, then increase to n {approx} 10{sup 25} - 10{sup 26} m{sup -3} and Te {approx} Ti {approx} 100 eV as stagnation is approached over a 1 meter radial distance. The large range of densities (4-5 orders of magnitude), initially cold plasma, and short optical depth as the jets merge make diagnosing the plasma a particularly challenging problem. Initial diagnostics will include multi-chord visible interferometry and polarimetry, Schlieren imaging, visible and V-UV spectroscopy, fast 1-dimensional imaging diode arrays, fast visible cameras, bolometry, magnetic and electrostatic probes, and pressure sensitive 'witness plates' to measure pressure and jet

  12. A semi-analytic model of magnetized liner inertial fusion

    OpenAIRE

    McBride, Ryan D.; Slutz, Stephen A.

    2015-01-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression...

  13. International Education Hubs: Collaboration for Competitiveness and Sustainability

    Science.gov (United States)

    Knight, Jane

    2014-01-01

    This chapter focuses on the development of education hubs, a recent phenomenon in international higher education. Three models of hubs are examined in relation to the forces, risks, and opportunities of globalization and how local and international collaborations are essential for both global competitiveness and sustainability.

  14. Soft Power and Cultural Diplomacy: Emerging Education Hubs in Asia

    Science.gov (United States)

    Lee, Jack T.

    2015-01-01

    Several education hubs have emerged in Asia and the Middle East in recent years with a specific focus on cross-border higher education. Through considerable efforts in policy planning and generous funding, these hubs aim to transform a country or city into an eminent destination for education, research, and training. The inherent design of these…

  15. Optimal Model and Solution of Railway Hub Shift Working Plan

    Institute of Scientific and Technical Information of China (English)

    He Shiwei; Zhu Songnian; Lin Boliang

    1996-01-01

    Aiming at decreasing the hub transportation costs, a railway hub shift working plan in terms of multicommodity network flow model is set up for considering the coordination of freight working, train working and locomotive working plans. The solution and the calculating results are also introduced.

  16. Phased arrays: inline flow line hub inspection using phased arrays

    NARCIS (Netherlands)

    Bloom, J.G.P.; Chougrani, K.; Rundberg, H.; Oldenziel, G.; Deleye, X.; Martina, Q.

    2011-01-01

    The feasibility of the inspection of flow line hubs using the phased array technique was investigated to determine the surface area of the seal area degraded by corrosion. A clean model of the hub was simulated to gain insight into the geometrical echoes and to determine the area covered by the ultr

  17. A versatile framework for cooperative hub network development

    NARCIS (Netherlands)

    Cruijssen, F.C.A.M.; Borm, P.; Dullaert, W.; Hamers, H.

    2010-01-01

    This paper introduces a framework for cooperative hub network development. Building a joint physical hub for the transshipment of goods is expensive and, therefore, involves considerable risks for cooperating companies. In a practical setting, it is unlikely that an entire network will be built at o

  18. Education Hubs: A Fad, a Brand, an Innovation?

    Science.gov (United States)

    Knight, Jane

    2011-01-01

    The last decade has seen significant changes in all aspects of internationalization but most dramatically in the area of education and research moving across national borders. The most recent developments are education hubs. The term "education hub" is being used by countries who are trying to build a critical mass of local and foreign…

  19. Soft Power and Cultural Diplomacy: Emerging Education Hubs in Asia

    Science.gov (United States)

    Lee, Jack T.

    2015-01-01

    Several education hubs have emerged in Asia and the Middle East in recent years with a specific focus on cross-border higher education. Through considerable efforts in policy planning and generous funding, these hubs aim to transform a country or city into an eminent destination for education, research, and training. The inherent design of these…

  20. Climate programs update: USDA Southwest Regional Climate Hub update

    Science.gov (United States)

    PROGRAM OVERVIEW: The overarching goal of the USDA SW Climate Hub is to assist farmers, ranchers and foresters in addressing the effects of climate change including prolonged drought, increased insect outbreaks and severe wildfires. In the first year of operations, the SW Climate Hub (est. Februa...

  1. International Education Hubs: Collaboration for Competitiveness and Sustainability

    Science.gov (United States)

    Knight, Jane

    2014-01-01

    This chapter focuses on the development of education hubs, a recent phenomenon in international higher education. Three models of hubs are examined in relation to the forces, risks, and opportunities of globalization and how local and international collaborations are essential for both global competitiveness and sustainability.

  2. Recycling of merchant ships

    Directory of Open Access Journals (Sweden)

    Magdalena Klopott

    2013-12-01

    Full Text Available The article briefly outlines the issues concerning ship recycling. It highlights ships' high value as sources of steel scrap and non-ferrous metals, without omitting the fact that they also contain a range of hazardous substances. Moreover, the article also focuses on basic ship demolition methods and their environmental impact, as well as emphasizes the importance of “design for ship recycling” philosophy.

  3. Multifunctional Metal Matrix Composite Filament Wound Tank Liners Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Metal Matrix Composite (MMC) materials offer tremendous potential for lightweight propellant and pressurant tankage for space applications. Thin MMC liners for COPVs...

  4. Use of natural zeolites as a landfill liner.

    Science.gov (United States)

    Tuncan, Ahmet; Tuncan, Mustafa; Koyuncu, Hakan; Guney, Yucel

    2003-02-01

    The purpose of this study is to investigate certain features of a novel material proposed to serve as an impervious liner in landfills. Various ratios of bentonites and zeolites (B/Z) compacted at optimum water content were tested to determine the strength parameters, permeability, pH, heavy metals and other properties. A B/Z ratio of 0.10 was found to be an ideal landfill liner material regarding its low hydraulic conductivity and high cation exchange capacity. The use of B/Z mixtures as an alternative to clay liners would provide potential to significantly reduce the thickness of base liner for landfills.

  5. Manufacturing hollow obturator with resilient denture liner on post hemimaxillectomy

    Directory of Open Access Journals (Sweden)

    Michael Josef Kridanto Kamadjaja

    2006-03-01

    Full Text Available A resilient denture liner is placed in the part of the hollow obturator base that contacts to post hemimaxillectomy mucosa. Replacing the resilient denture liner can makes the hollow obturator has an intimate contact with the mucosa, so it can prevents the mouth liquid enter to the cavum nasi and sinus, also eliminates painful because of using the hollow obturator. Resilient denture liner is a soft and resilient material that applied to the fitting surface of a denture in order to allow a more distribution of load. A case was reported about using the hollow obturator with resilient denture liner on post hemimaxillectomy to overcome these problems.

  6. Variable-Depth Liner Evaluation Using Two NASA Flow Ducts

    Science.gov (United States)

    Jones, M. G.; Nark, D. M.; Watson, W. R.; Howerton, B. M.

    2017-01-01

    Four liners are investigated experimentally via tests in the NASA Langley Grazing Flow Impedance Tube. These include an axially-segmented liner and three liners that use reordering of the chambers. Chamber reordering is shown to have a strong effect on the axial sound pressure level profiles, but a limited effect on the overall attenuation. It is also shown that bent chambers can be used to reduce the liner depth with minimal effects on the attenuation. A numerical study is also conducted to explore the effects of a planar and three higher-order mode sources based on the NASA Langley Curved Duct Test Rig geometry. A four-segment liner is designed using the NASA Langley CDL code with a Python-based optimizer. Five additional liner designs, four with rearrangements of the first liner segments and one with a redistribution of the individual chambers, are evaluated for each of the four sources. The liner configuration affects the sound pressure level profile much more than the attenuation spectra for the planar and first two higher-order mode sources, but has a much larger effect on the SPL profiles and attenuation spectra for the last higher-order mode source. Overall, axially variable-depth liners offer the potential to provide improved fan noise reduction, regardless of whether the axially variable depths are achieved via a distributed array of chambers (depths vary from chamber to chamber) or a group of zones (groups of chambers for which the depth is constant).

  7. The 4 Pi Sky Transient Alerts Hub

    CERN Document Server

    Staley, Tim D

    2016-01-01

    We introduce the 4 Pi Sky 'hub', a collection of open data-services and underlying software packages built for rapid, fully automated reporting and response to astronomical transient alerts. These packages build on the mature 'VOEvent' standardized message-format, and aim to provide a decentralized and open infrastructure for handling transient alerts. In particular we draw attention to the initial release of voeventdb, an archive and remote-query service that allows astronomers to make historical queries about transient alerts. By employing spatial filters and web-of-citation lookups, voeventdb enables cross-matching of transient alerts to bring together data from multiple sources, as well as providing a point of reference when planning new follow-up campaigns. We also highlight the recent addition of optical-transient feeds from the ASASSN and GAIA projects to our VOEvent distribution stream. Both the source-code and deployment-scripts which implement these services are freely available and permissively lic...

  8. On the Predictability of Hub Height Winds

    DEFF Research Database (Denmark)

    Draxl, Caroline

    Wind energy is a major source of power in over 70 countries across the world, and the worldwide share of wind energy in electricity consumption is growing. The introduction of signicant amounts of wind energy into power systems makes accurate wind forecasting a crucial element of modern electrical...... grids. These systems require forecasts with temporal scales of tens of minutes to a few days in advance at wind farm locations. Traditionally these forecasts predict the wind at turbine hub heights; this information is then converted by transmission system operators and energy companies into predictions...... of power output at wind farms. Since the power available in the wind is proportional to the wind speed cubed, even small wind forecast errors result in large power prediction errors. Accurate wind forecasts are worth billions of dollars annually; forecast improvements will result in reduced costs...

  9. Location of Urban Logistic Terminals as Hub Location Problem

    Directory of Open Access Journals (Sweden)

    Jasmina Pašagić Škrinjar

    2012-09-01

    Full Text Available In this paper the problems of locating urban logistic terminals are studied as hub location problems that due to a large number of potential nodes in big cities belong to hard non-polynomial problems, the so-called NP-problems. The hub location problems have found wide application in physical planning of transport and telecommunication systems, especially systems of fast delivery, networks of logistic and distribution centres and cargo traffic terminals of the big cities, etc. The paper defines single and multiple allocations and studies the numerical examples. The capacitated single allocation hub location problems have been studied, with the provision of a mathematical model of selecting the location for the hubs on the network. The paper also presents the differences in the possibilities of implementing the exact and heuristic methods to solve the actual location problems of big dimensions i.e. hub problems of the big cities.

  10. Hub exchange operations in intermodal hub-and spoke networks : a performance comparison of rail-rail exchange facilities

    NARCIS (Netherlands)

    Bontekoning, Y.M.

    2006-01-01

    The implementation of hub-and-spoke networks in intermodal transport is suggested as one of the potential solutions for helping to increase the intermodal market share. Traditionally, trains are shunted at hubs; this is a time-consuming process. Since the early 1990s a new type of intermodal termina

  11. ONERA-NASA Cooperative Effort on Liner Impedance Eduction

    Science.gov (United States)

    Primus, Julien; Piot, Estelle; Simon, Frank; Jones, Michael G.; Watson, Willie R

    2013-01-01

    As part of a cooperation between ONERA and NASA, the liner impedance eduction methods developed by the two research centers are compared. The NASA technique relies on an objective function built on acoustic pressure measurements located on the wall opposite the test liner, and the propagation code solves the convected Helmholtz equation in uniform ow using a finite element method that implements a continuous Galerkin discretization. The ONERA method uses an objective function based either on wall acoustic pressure or on acoustic velocity acquired above the liner by Laser Doppler Anemometry, and the propagation code solves the linearized Euler equations by a discontinuous Galerkin discretization. Two acoustic liners are tested in both ONERA and NASA ow ducts and the measured data are treated with the corresponding impedance eduction method. The first liner is a wire mesh facesheet mounted onto a honeycomb core, designed to be linear with respect to incident sound pressure level and to grazing ow velocity. The second one is a conventional, nonlinear, perforate-over-honeycomb single layer liner. Configurations without and with ow are considered. For the nonlinear liner, the comparison of liner impedance educed by NASA and ONERA shows a sensitivity to the experimental conditions, namely to the nature of the source and to the sample width.

  12. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  13. CONSTRUCTION, MONITORING, AND PERFORMANCE OF TWO SOIL LINERS

    Science.gov (United States)

    A prototype soil liner and a field-scale soil liner were constructed to test whether compacted soil barrier systems could be built to meet the standard set by the U.S. Environmental Protection Agency (EPA) for saturated hydraulic conductivity (< 1 x 10'7 cm/s). In situ ponded inf...

  14. Tissue Friendly Pendulum: Soft Liner to prevent Tissue Irritation

    Directory of Open Access Journals (Sweden)

    Siddharth Shashidhar Revankar

    2014-01-01

    Full Text Available Palatal mucosal irritation is commonly encountered with the Pendulum appliance. The efficiency of soft liners in reducing tissue irritation has been well documented in the field of prosthodontics. The following article describes an innovative technique where soft liner can be used to reduce palatal mucosal irritation caused by pendulum appliance.

  15. Flow Merging and Hub Route Optimization in Collaborative Transportation

    Directory of Open Access Journals (Sweden)

    Kerui Weng

    2014-01-01

    Full Text Available This paper studies the optimal hub routing problem of merged tasks in collaborative transportation. This problem allows all carriers’ transportation tasks to reach the destinations optionally passing through 0, 1, or 2 hubs within limited distance, while a cost discount on arcs in the hub route could be acquired after paying fixed charges. The problem arises in the application of logistics, postal services, airline transportation, and so forth. We formulate the problem as a mixed-integer programming model, and provide two heuristic approaches, respectively, based on Lagrangian relaxation and Benders decomposition. Computational experiments show that the algorithms work well.

  16. GitHub open source project recommendation system

    OpenAIRE

    Matek, Tadej; Zebec, Svit Timej

    2016-01-01

    Hosting platforms for software projects can form collaborative social networks and a prime example of this is GitHub which is arguably the most popular platform of this kind. An open source project recommendation system could be a major feature for a platform like GitHub, enabling its users to find relevant projects in a fast and simple manner. We perform network analysis on a constructed graph based on GitHub data and present a recommendation system that uses link prediction.

  17. The Opportunities and Threats of Turning Airports into Hubs

    Science.gov (United States)

    Kraus, Andreas; Koch, Benjamin

    2006-01-01

    This paper examines the opportunities and threats which arise when turning origin/destination airports into hubs. The analysis focuses on market development trends, competitive structures, especially in the light of airline network strategies and the growing rivalry between airports, and finally the potential financial impacts for the airport, including both investment efforts and the financial results from hub operations. We argue that in most cases a decision against converting a traditional origin/destination airport into a major transfer point is preferable to the transformation into a hub.

  18. Liquid butane filled load for a liner driven Pegasus experiment

    CERN Document Server

    Salazar, M A; Atchison, W; Armijo, E; Bartos, Yu; García, F; Randolph, B; Sheppard, M G

    2001-01-01

    Summary form only given, as follows. A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment required massive tungsten glide planes for inertial confinement of the liner fill media during implosion. Shallow sinusoidal perturbations were machined on the inside surface of the liner to seed instabilities, also true of the previous experiments. Butane was selected for a relatively low equilibrium vapor pressure, a practical attribute for use in the Pegasus vacuum power flow channel. Butane safety topics at Pegasus will be addressed. Glide planes were sealed to the liner by use of butane compatible o-rings. A sintered form of tungsten was used for the glide planes to facilitate machining the relatively complex shapes that were required. Porosity of the tungsten was sea...

  19. Evaluating the accuracy of wear formulae for acetabular cup liners.

    Science.gov (United States)

    Wu, James Shih-Shyn; Hsu, Shu-Ling; Chen, Jian-Horng

    2010-02-01

    This study proposes two methods for exploring the wear volume of a worn liner. The first method is a numerical method, in which SolidWorks software is used to create models of the worn out regions of liners at various wear directions and depths. The second method is an experimental one, in which a machining center is used to mill polyoxymethylene to manufacture worn and unworn liner models, then the volumes of the models are measured. The results show that the SolidWorks software is a good tool for presenting the wear pattern and volume of a worn liner. The formula provided by Ilchmann is the most suitable for computing liner volume loss, but is not accurate enough. This study suggests that a more accurate wear formula is required. This is crucial for accurate evaluation of the performance of hip components implanted in patients, as well as for designing new hip components.

  20. Suzaku observation of the LINER NGC 4102

    CERN Document Server

    Gonzalez-Martin, O; Braito, V; Masegosa, J; Marquez, I; Mateos, S; Acosta-Pulido, J A; Martinez, M A; Ebrero, J; Esquej, P; O'Brien, P; Tueller, J; Warwick, R S; Watson, M G

    2010-01-01

    Low ionisation nuclear emission-line region (LINER) nuclei have been claimed to be different than other active galactic nuclei (AGN) due to the presence of complex absorbing structures along the line-of-sight and/or an inefficient mode of accretion onto the supermassive black hole. However, this issue is still open. We have investigated the broad band X-ray spectrum of NGC 4102, one of the most luminous LINERs in the Swift/BAT survey. We studied a 80 ksec Suzaku spectrum of NGC 4102, together with archival Chandra and Swift/BAT observations. We also studied the optical (3.5m/TWIN at Calar Alto observatory) and near-infrared (WHT/LIRIS at Observatorio Roque los Muchachos) spectra that were taken contemporaneous to the Suzaku data. There is strong evidence that NGC 4102 is a Compton-thick AGN, as suggested by the Swift/BAT detected intrinsic continuum and the presence of a strong narrow, neutral FeKa emission line. We have also detected ionised FeXXV emission lines in the Suzaku spectrum of the source. NGC 4102...

  1. Gorgon simulations of Magnetized Liner Inertial Fusion

    Science.gov (United States)

    Roeltgen, Jonathan; Jennings, Christopher; Sefkow, Adam; Slutz, Stephen

    2012-10-01

    Substantial fusion yields are predicted with pulsed power machines driving cylindrical liner implosions with preheated and magnetized deuterium-tritium [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)]. The Rayleigh-Taylor instability is the most likely mechanism that could degrade the fusion yield of this concept which we call Magnetized Liner Inertial Fusion (MagLIF). Gorgon is a 3D magnetohydrodynamics code that is well suited to simulating the effects of 3D Magneto-Rayleigh-Taylor instabilities. It has successfully simulated wire array z-pinches in 3D. We plan to use Gorgon to simulate the MagLIF concept in 3D, but first we are performing 1D simulations to test the essential physics necessary to simulate the MagLIF concept, for example bremsstrahlung losses from the fuel and the inhibition of transport by the magnetic field. We will present 1D Gorgon results of optimized MagLIF yields as a function of drive current.

  2. User experience of transtibial prosthetic liners: A systematic review.

    Science.gov (United States)

    Richardson, Amy; Dillon, Michael P

    2017-02-01

    The liner is an integral part of a transtibial prosthesis designed to protect the residual limb, enhance comfort and provide suspension. Literature is difficult to interpret and use given the variety of interventions, outcome measures and method designs. Critical appraisal and synthesis of the evidence is needed to help inform decisions about liner prescription based on the user experience. To critically appraise and synthesise research describing the user experience of transtibial prosthetic liners. Systematic review. A comprehensive suite of databases were searched using terms related to amputation level, liner type and user experience. Included studies were in English and measured the first-person experience of using a transtibial liner. Studies were appraised using the McMaster University Critical Review Forms. A total of 18 articles met the inclusion criteria. While the quality of the evidence has improved over time, a number of common issues (e.g. sampling bias, validity of outcome measures, incorrect inferential analysis) reduce our ability to differentiate between the user experience of different transtibial liners. There is insufficient research to differentiate between the user experience of different transtibial liners. High-quality research is needed to inform decisions about liner prescription based on the user experience. Clinical relevance The available evidence suggests that the user experience of commonly reported problems (e.g. sweating) may be very similar between different liners. Aspects of the user experience that differ most between liners (e.g. unwanted noises, rotation within the socket) can help focus attention on what matters most when discussing prescription.

  3. A Hedonism Hub in the Human Brain

    Science.gov (United States)

    Zacharopoulos, G.; Lancaster, T. M.; Bracht, T.; Ihssen, N.; Maio, G. R.; Linden, D. E. J.

    2016-01-01

    Human values are abstract ideals that motivate behavior. The motivational nature of human values raises the possibility that they might be underpinned by brain structures that are particularly involved in motivated behavior and reward processing. We hypothesized that variation in subcortical hubs of the reward system and their main connecting pathway, the superolateral medial forebrain bundle (slMFB) is associated with individual value orientation. We conducted Pearson's correlation between the scores of 10 human values and the volumes of 14 subcortical structures and microstructural properties of the medial forebrain bundle in a sample of 87 participants, correcting for multiple comparisons (i.e.,190). We found a positive association between the value that people attach to hedonism and the volume of the left globus pallidus (GP).We then tested whether microstructural parameters (i.e., fractional anisotropy and myelin volume fraction) of the slMFB, which connects with the GP, are also associated to hedonism and found a significant, albeit in an uncorrected level, positive association between the myelin volume fraction within the left slMFB and hedonism scores. This is the first study to elucidate the relationship between the importance people attach to the human value of hedonism and structural variation in reward-related subcortical brain regions. PMID:27473322

  4. Idea Hubs as Nexus of Collective Creativity in Digital Innovation

    DEFF Research Database (Denmark)

    Ciriello, Raffaele; Richter, Alexander

    2015-01-01

    on instances of idea hubs in two multinational European software companies, where we conducted a case study over a two-year period, and collected data in form of interviews, digital documents, and participant observations. In doing so, we identify a set of social networking practices in which idea hubs serve......Digital innovation radically transforms the nature of corporate innovation practices, implying a growing need for deeper understanding its origins and outcomes. In this paper, we conceptualize the focal points of social networking in digital innovation as idea hubs. We focus our analysis...... as nexus of collective creativity and subject these to a critical dialectical examination. We discuss three influencing factors of idea hub choice, namely material infrastructure, innovation process phase, and personal characteristics. These explain why in a corporate environment, despite a variety...

  5. 14 CFR 398.2 - Number and designation of hubs.

    Science.gov (United States)

    2010-01-01

    ... origin and designation data; (iv) The distance of candidate hubs from the eligible place; and (v) The... may instead require that service from an eligible place be provided to a nearby focal point...

  6. Model of Controlling the Hubs in P2P Networks

    Directory of Open Access Journals (Sweden)

    Yuhua Liu

    2009-06-01

    Full Text Available Research into the hubs in Peer-to-Peer (P2P networks, and present a new method to avoid generating the hubs in the networks by controlling the logical topology structure of P2P networks. We firstly introduce the controlling ideas about hierarchizing the hubs. Then, we disclose and interpret the controlling model, and give out the concrete method to carry it out. Finally, we validate our controlling model via simulations and the simulation results demonstrate that our work is effective to control the hubs in P2P networks. Thus, this model can improve the network competence to defend against coordinated attacks, promote the network robustness, and ensure the network would develop continually and healthily.

  7. A Flexible Logistics Distribution Hub Model considering Cost Weighted Time

    Directory of Open Access Journals (Sweden)

    Wenxue Ran

    2017-01-01

    Full Text Available The delivery time of order has become an important fact for customers to evaluate logistics services. Due to the diverse and large quantities of orders in the background of electronic commerce, how to improve the flexibility of distribution hub and reduce the waiting time of customers becomes one of the most challenging questions for logistics companies. With this in mind, this paper proposes a new method of flexibility assessment in distribution hub by introducing cost weighted time (CWT. The advantages of supply hub operation mode in delivery flexibility are verified by the approach: the mode has pooling effects and uniform distribution characteristics; these traits can reduce overlapping delivery time to improve the flexibility in the case of two suppliers. Numerical examples show that the supply hub operation mode is more flexible than decentralized distribution operation mode in multidelivery cycles.

  8. Buckling of Ship Structures

    CERN Document Server

    Shama, Mohamed

    2013-01-01

    Buckling of Ship Structures presents a comprehensive analysis of the buckling problem of ship structural members. A full analysis of the various types of loadings and stresses imposed on ship plating and primary and secondary structural members is given. The main causes and consequences of the buckling mode of failure of ship structure and the methods commonly used to control buckling failure are clarified. This book contains the main equations required to determine the critical buckling stresses for both ship plating and the primary and secondary stiffening structural members. The critical buckling stresses are given for ship plating subjected to the induced various types of loadings and having the most common boundary conditions encountered in ship structures.  The text bridges the gap existing in most books covering the subject of buckling of ship structures in the classical analytical format, by putting the emphasis on the practical methods required to ensure safety against buckling of ship structur...

  9. Establishing a Global Halal Hub: In-Depth Interviews

    Directory of Open Access Journals (Sweden)

    Mahdi Borzooei

    2013-10-01

    Full Text Available The purpose of this study is to explore the requirements needed for a country to establish itself as a global Halal hub. In this regard, this exploratory research paper uses a semi-structured in-depth interview to obtain the perceptions of Halal experts about the requirements for establishing a Halal hub. The results of the study indicate that human capital, media, research and development, events, country’s capability, public and governmental support, marketing strategy, and infrastructure comprise the vital requirements. Furthermore, from the perceptions of the experts, public and governmental support, marketing strategy, and human capital are the three most important requirements. Since this paper is an exploratory study, it provides some insights of the three experts on the establishing of a Halal hub. In addition, a quantitative study is an appropriate approach to implement the findings of this study empirically and to determine the effective components to establish a Halal hub in those countries that desire it. A practical implication of this study is the opening of a new window for any country that aspires to be a Halal hub. In this matter, this paper presents the key considerations in establishing a Halal hub for Halal certification bodies, companies and marketers involved in the Halal business. Moreover, this research attempts to influence the perceptions and attitudes of people of the country on the desirability of becoming a Halal hub, followed by a discussion on the development of a national brand. When the contribution of its people is high, a country stands the best chance of achieving its goal. Finally, this study is one of the first to seek the perceptions of experts about vital requirements that a country should pay more attention to if it wishes to establish a global Halal hub.

  10. A Hub Matrix Theory and Applications to Wireless Communications

    Directory of Open Access Journals (Sweden)

    Kung HT

    2007-01-01

    Full Text Available This paper considers communications and network systems whose properties are characterized by the gaps of the leading eigenvalues of for a matrix . It is shown that a sufficient and necessary condition for a large eigen-gap is that is a "hub" matrix in the sense that it has dominant columns. Some applications of this hub theory in multiple-input and multiple-output (MIMO wireless systems are presented.

  11. Why do European companies have Innovation Hubs in Silicon Valley

    DEFF Research Database (Denmark)

    Berger, Andreas; Brem, Alexander

    2017-01-01

    Innovation hubs are gaining high attention in recent years, especially from European companies. Silicon Valley has been deemed as one of the most attractive and successful environments for establishing innovation hubs. This article highlights examples of companies from Europe that made the step t...... to California—namely, Volkswagen, Swisscom, BMW, Axel Springer, Munich Re, and Innogy SE (RWE Group). Based on these companies’ experiences, recommendations are given on how companies might approach a setup in Silicon Valley for long-term success....

  12. Concerted perturbation observed in a hub network in Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Dapeng Liang

    Full Text Available Alzheimer's disease (AD is a progressive neurodegenerative disease involving the alteration of gene expression at the whole genome level. Genome-wide transcriptional profiling of AD has been conducted by many groups on several relevant brain regions. However, identifying the most critical dys-regulated genes has been challenging. In this work, we addressed this issue by deriving critical genes from perturbed subnetworks. Using a recent microarray dataset on six brain regions, we applied a heaviest induced subgraph algorithm with a modular scoring function to reveal the significantly perturbed subnetwork in each brain region. These perturbed subnetworks were found to be significantly overlapped with each other. Furthermore, the hub genes from these perturbed subnetworks formed a connected hub network consisting of 136 genes. Comparison between AD and several related diseases demonstrated that the hub network was robustly and specifically perturbed in AD. In addition, strong correlation between the expression level of these hub genes and indicators of AD severity suggested that this hub network can partially reflect AD progression. More importantly, this hub network reflected the adaptation of neurons to the AD-specific microenvironment through a variety of adjustments, including reduction of neuronal and synaptic activities and alteration of survival signaling. Therefore, it is potentially useful for the development of biomarkers and network medicine for AD.

  13. Prediction of Cone Crusher Performance Considering Liner Wear

    Directory of Open Access Journals (Sweden)

    Yanjun Ma

    2016-12-01

    Full Text Available Cone crushers are used in the aggregates and mining industries to crush rock material. The pressure on cone crusher liners is the key factor that influences the hydraulic pressure, power draw and liner wear. In order to dynamically analyze and calculate cone crusher performance along with liner wear, a series of experiments are performed to obtain the crushed rock material samples from a crushing plant at different time intervals. In this study, piston die tests are carried out and a model relating compression coefficient, compression ratio and particle size distribution to a corresponding pressure is presented. On this basis, a new wear prediction model is proposed combining the empirical model for predicting liner wear with time parameter. A simple and practical model, based on the wear model and interparticle breakage, is presented for calculating compression ratio of each crushing zone along with liner wear. Furthermore, the size distribution of the product is calculated based on existing size reduction process model. A method of analysis of product size distribution and shape in the crushing process considering liner wear is proposed. Finally, the validity of the wear model is verified via testing. The result shows that there is a significant improvement of the prediction of cone crusher performance considering liner wear as compared to the previous model.

  14. The influence of liners on the pulp inflammation

    Directory of Open Access Journals (Sweden)

    Davidović Lado

    2015-01-01

    Full Text Available Introduction. The study included application of liners and dental composites in to cavities of six experimental animals - rabbits (Oryctolagus cuniculus. Objective. The aim of the study was to investigate rabbit dental pulp response to different liners. Methods. Cavity preparation for class V were made on the maxillary central incisors and one lower incisor, while the second lower incisor served as a control tooth. These teeth were restored with the use of one of the following liners - Calcimol LC, ANA Liner and Fuji II LC Improved, and Ceram-X mono dental composite. After an observation period of five days animals were sacrificed and prepared for histological analysis. The existence and degree of the pulp inflammation was determined by using a light microscope. Results. Results showed that the used liners do not cause distortion of the structure and continuity of the odontoblastic layer. Inflammation was not registered in the control group, while in each group of tested materials one tooth with mild signs of hyperemia was registered. Results showed that all three tested liners demonstrated favorable effects on the pulp of the tooth and did not lead to inflammatory reactions. Conclusion. Histological analysis of the dental pulp of experimental animals suggests that the liners used in this study do not compromise the integrity of the odontoblastic layer, if it is applied over a thin layer of dentin. In each group of tested materials one tooth with mild signs of hyperemia and vasodilation was registered.

  15. Crushing Strength of Ship Structures

    DEFF Research Database (Denmark)

    Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

    1999-01-01

    The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

  16. Crushing Strength of Ship Structures

    DEFF Research Database (Denmark)

    Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

    1999-01-01

    The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

  17. Ozone production efficiency of a ship-plume: ITCT 2K2 case study.

    Science.gov (United States)

    Kim, Hyun S; Kim, Yong H; Han, Kyung M; Kim, Jhoon; Song, Chul H

    2016-01-01

    Ozone production efficiency (OPE) of ship plume was first evaluated in this study, based on ship-plume photochemical/dynamic model simulations and the ship-plume composition data measured during the ITCT 2K2 (Intercontinental Transport and Chemical Transformation 2002) aircraft campaign. The averaged instantaneous OPEs (OPE(i)‾) estimated via the ship-plume photochemical/dynamic modeling for the ITCT 2K2 ship-plume ranged between 4.61 and 18.92, showing that the values vary with the extent of chemical evolution (or chemical stage) of the ship plume and the stability classes of the marine boundary layer (MBL). Together with OPE(i)‾, the equivalent OPEs (OPE(e)‾) for the entire ITCT 2K2 ship-plume were also estimated. The OPE(e)‾ values varied between 9.73 (for the stable MBL) and 12.73 (for the moderately stable MBL), which agreed well with the OPE(e)‾ of 12.85 estimated based on the ITCT 2K2 ship-plume observations. It was also found that both the model-simulated and observation-based OPE(e)‾ inside the ship-plume were 0.29-0.38 times smaller than the OPE(e)‾ calculated/measured outside the ITCT 2K2 ship-plume. Such low OPEs insides the ship plume were due to the high levels of NO and non-liner ship-plume photochemistry. Possible implications of this ship-plume OPE study in the global chemistry-transport modeling are also discussed.

  18. Rehabilitation of underwater pipeline with liner; Reabilitacao de aqueduto submarino com liner: multiplas vantagens e aplicacoes

    Energy Technology Data Exchange (ETDEWEB)

    Aquino, Roberto S.; Oliveira, Jose N. de; Urtiga, Rogerio L.; Witt, R. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The system of water injection in XAREU oil production field has an water pipeline sizing 4'' of diameter, between the offshore platform PXA-1 and another PXA-2, that it transfers 165 m{sup 3}/d of salt water for pressurization of the reservoir through the injection well Xareu-23. This water pipeline always presented high degree of corrosion needing frequently installation of cramps to eliminate leakages. After evaluating the costs we conclude that the more attractive it would be the installation of a liner than the launching of a new water pipeline. For the installation of a new water pipeline we would need the approval of IBAMA and of a great number of resources for the substitution of that pipeline. In spite of treating of an unpublished service between two offshore platforms we chose for the installation of a liner, because we had a great technological domain in this service in onshore oil production facilities with many pipelines recovered with this technique. We had to revise all of the procedures so that there was not any surprise to make unfeasible this service. The installation of the system liner, consisted of an internal coating 'in situ' through the insert of plastic tubes(high density polyethylene-HDPE), that it forms a barrier between the pipeline and the transported fluid. (author)

  19. The magnetically driven imploding liner parameter space of the ATLAS capacitor bank

    CERN Document Server

    Lindemuth, I R; Faehl, R J; Reinovsky, R E

    2001-01-01

    Summary form only given, as follows. The Atlas capacitor bank (23 MJ, 30 MA) is now operational at Los Alamos. Atlas was designed primarily to magnetically drive imploding liners for use as impactors in shock and hydrodynamic experiments. We have conducted a computational "mapping" of the high-performance imploding liner parameter space accessible to Atlas. The effect of charge voltage, transmission inductance, liner thickness, liner initial radius, and liner length has been investigated. One conclusion is that Atlas is ideally suited to be a liner driver for liner-on-plasma experiments in a magnetized target fusion (MTF) context . The parameter space of possible Atlas reconfigurations has also been investigated.

  20. Liners for ion transport membrane systems

    Science.gov (United States)

    Carolan, Michael Francis; Miller, Christopher Francis

    2010-08-10

    Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

  1. A sensate liner for personnel monitoring applications

    Science.gov (United States)

    Lind, Eric J.; Jayaraman, Sundaresan; Park, Ms. Sungmee; Rajamanickam, Rangaswamy; Eisler, Robert, , Dr.; Burghart, Mr. George; McKee, Mr. Tony

    This program develops and demonstrates technologies useful for implementing a manageable cost effective systems approach to monitoring the medical condition of personnel by way of an instrumented uniform hereafter referred to as a Sensate Liner (SL). The SL consists of a form fitting garment which contains and interconnects sensing elements and devices to an electronics pack containing a processor and transmitter. The SL prototype requires fiber, textile, garment and sensor development. The SL textile consists of a mesh of electrically and optically conductive fibers integrated into the normal structure (woven or knitted) of fibers and yarns selected for comfort and durability. A suite of SL garment compatible embedded biological and physical sensors are then integrated into the SL. The initial SL sensor suite is selected to improve triage for combat casualties. Additional SL sensor concepts for medical monitoring will be discussed.

  2. Advanced Combustor Liner Cooling Technology for Gas Turbines

    Directory of Open Access Journals (Sweden)

    Aspi R. Wadia

    1988-10-01

    Full Text Available This paper briefly reviews some of the work on advanced liner cooling techniques - specificially laminated porous wall cooling, angled-multihole (effusion cooling and composite metal matrix liner cooling. The concept definition, heat transfer design procedure and design problems including key materials and fabrication considerations associated with each basic concept will be reviewed. Published rig and engine experience of aircraft engine manufacturers and research organizations will be cited. Some logical extensions of the current liner cooling schemes are suggested for future applications.

  3. Shipping Information Pipeline

    DEFF Research Database (Denmark)

    Jensen, Thomas; Vatrapu, Ravi

    2015-01-01

    This paper presents a design science approach to solving persistent problems in the international shipping eco system by creating the missing common information infrastructures. Specifically, this paper reports on an ongoing dialogue between stakeholders in the shipping industry and information s...... impacts on global trade and local economies....

  4. Shipping Information Pipeline

    DEFF Research Database (Denmark)

    Jensen, Thomas; Vatrapu, Ravi

    2015-01-01

    This paper presents a design science approach to solving persistent problems in the international shipping eco system by creating the missing common information infrastructures. Specifically, this paper reports on an ongoing dialogue between stakeholders in the shipping industry and information s...

  5. Effective and Safe Ships

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Amdahl, Jørgen; Rutgersson, Olle

    1996-01-01

    A Joint Nordic Research project "Effecive and Safe Ships" is presented. The project is aiming to develop methods and tools for quantitative evaluation fo ship safety. This report is the report of the preliminary phase where the plan for the main project is developed. The objectives of the project...

  6. Can the liner be landed on the well bottom?; Posso apoiar o liner no fundo do poco?

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Carlos Fernando Humbert [PETROBRAS, Rio de Janeiro, RJ (Brazil). Departamento de Perfuracao. Div. de Suporte Tecnico

    1994-07-01

    During the 7 in.liner run-in operation in well 1-BSS-65 with the shoe depth at 2400 m, the setting string broke and, as a result, the whole array fell from 2800 m high. Through a fishing operation, the liner (setting tool) was recovered and later a casing string sticking was detected. Full fluid circulation was obtained and the possibility was considered of cementing the liner in that position. At this point three questions were asked to assess the feasibility of such a cementing operation: were there significant damages inflicted on the liner string as a result of the fall?; if no damages resulted from the fall, would liner bucking prevent the running in of completion tools?; would the casing withstand the strains caused by buckling? This paper addresses the two latter questions through the theory of helical bucking of the tubing confined within a cylinder. Equations are introduced to calculate the helical pitch and the axial strain due to bending. A user-friendly computer program was developed to apply this theory to instances such as the above-mentioned one or to eliminate the use of hangers with short liners. The results of the analysis carried out on this particular well are presented and an assessment of the main parameters bearing on the issue is undertaken. These parameters are: well diameter and liner length. (author)

  7. Identification of promising Twin Hub networks: Report of Work Package 1 of the Intermodal rail freight Twin hub Network Northwest Europe - project (final report)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.; Meijer, S.; Witteveen, C.; Meijers, B.M.; Pekin, E.; Macharis, C.; Kiel, J.; Kawabata, Y.; Vos, W.

    2014-01-01

    This report is the first deliverable of the project Intermodal Rail Freight Twin Hub Network Northwest Europe. We call its subject Twin hub network and the organisational entity to carry out the actions the Twin hub project. The project is funded by INTERREG NWE (programme IVb). Its work started in

  8. Liner «L’Aquitaine» (1899-1906

    Directory of Open Access Journals (Sweden)

    Jean Guiglini

    2016-09-01

    Full Text Available The paper gives a brief biography of the French liner «L'Aquitaine», before the Spanish auxiliary cruiser «Patriota». The article is illustrated with photographs from the collection of the author.

  9. Open Cell Conducting Foams for High Synchrotron Radiation Beam Liners

    CERN Document Server

    Petracca, Stefania

    2014-01-01

    The possible use of open-cell conductive foams in high synchrotron radiation particle accelerator beam liners is considered. Available materials and modeling tools are reviewed, potential pros and cons are discussed, and preliminary conclusions are drawn.

  10. Shear Strength Behavior of Two Landfill Clay Liners

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Direct shear tests were conducted to obtain both the shear strength of compacted clay liners (CCLs) specimens and the interface shear strength between compacted clay liner and base soil. These experiments were conducted under the conditions of five different water contents. The experimental results show that shear strength of both CCLs and CCLs/base interface decreases with the increase in the water content of CCLs and base soil. In addition, the considerate concentration of NaCl in leachate has no deteriorating effect on the shear strength of liners. Triaxial shear tests were also conducted on clay liner specimens to obtain total and effective shear strength under a fast compression. The shear strength c'=100 kPa for sand-bentonite, respectively. These results indicate that the compacted clay-bentonite shows normal consolidation, but that the compacted sand-bentonite exhibits over-consolidation.

  11. Liners of thermoplastic composites in oil field tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Melve, B. [Statoil Research Centre, Trondheim (Norway); Grini, K. [Univ. of Trondheim, Trondheim (Norway)

    1997-12-31

    The buckling resistance of thermoplastic composite liners in steel production tubing has been studied by theoretical models, numeric models and practical collapse tests. The materials studied were hoop wound glass fibre/polypropylene with and without a pure polypropylene inner layer. The numerical results show that a large increase in buckling resistance is achieved when the liner is partially supported by the steel tube in comparison with a free liner. The test results for the unsupported liner were in agreement with standard theories. The combined laminate did not perform as well as predicted because the polypropylene layer delaminated and buckled away from the composite layer. Thermoforming of the ends to suit the threaded end connectors was also shown to be possible. (au)

  12. Migration behavior of landfill leachate contaminants through alternative composite liners

    Energy Technology Data Exchange (ETDEWEB)

    Varank, Gamze, E-mail: gvarank@yildiz.edu.tr; Demir, Ahmet, E-mail: ahmetd@yildiz.edu.tr; Top, Selin, E-mail: stop@yildiz.edu.tr; Sekman, Elif, E-mail: esekman@yildiz.edu.tr; Akkaya, Ebru, E-mail: ekoca@yildiz.edu.tr; Yetilmezsoy, Kaan, E-mail: yetilmez@yildiz.edu.tr; Bilgili, M. Sinan, E-mail: mbilgili@yildiz.edu.tr

    2011-08-01

    Four identical pilot-scale landfill reactors with different alternative composite liners were simultaneously operated for a period of about 540 days to investigate and to simulate the migration behaviors of phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and heavy metals (Pb, Cu, Zn, Cr, Cd, Ni) from landfill leachate to the groundwater. Alternative landfill liners of four reactors consist of R1: Compacted clay liner (10 cm + 10 cm, k = 10{sup -8} m/sn), R2: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm + 10 cm, k = 10{sup -8} m/sn), R3: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10{sup -8} m/sn) + bentonite liner (2 cm) + compacted clay liner (10 cm, k = 10{sup -8} m/sn), and R4: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10{sup -8} m/sn) + zeolite liner (2 cm) + compacted clay liner (10 cm, k = 10{sup -8} m/sn). Wastes representing Istanbul municipal solid wastes were disposed in the reactors. To represent bioreactor landfills, reactors were operated by leachate recirculation. To monitor and control anaerobic degradation in the reactors, variations of conventional parameters (pH, alkalinity, chloride, conductivity, COD, TOC, TKN, ammonia and alcaly metals) were also investigated in landfill leachate samples. The results of this study showed that about 35-50% of migration of organic contaminants (phenolic compounds) and 55-100% of migration of inorganic contaminants (heavy metals) to the model groundwater could be effectively reduced with the use of bentonite and zeolite materials in landfill liner systems. Although leachate contaminants can reach to the groundwater in trace concentrations, findings of this study concluded that the release of these compounds from landfill leachate to the groundwater may potentially be of an important environmental concern based on the experimental findings. - Research highlights: {yields} Migration of

  13. Landing Gear Door Liners for Airframe Noise Reduction

    Science.gov (United States)

    Jones, Michael G. (Inventor); Howerton, Brian M. (Inventor); Van De Ven, Thomas (Inventor)

    2014-01-01

    A landing gear door for retractable landing gear of aircraft includes an acoustic liner. The acoustic liner includes one or more internal cavities or chambers having one or more openings that inhibit the generation of sound at the surface and/or absorb sound generated during operation of the aircraft. The landing gear door may include a plurality of internal chambers having different geometries to thereby absorb broadband noise.

  14. Star-powered LINERs in the Sloan Digital Sky Survey

    CERN Document Server

    Asari, N Vale; Fernandes, R Cid; Gomes, J M; Schlickmann, M; Mateus, A; Schoenell, W; Sodré, L

    2009-01-01

    Galaxies are usually classified as star forming or active by using diagnostic diagrams, such as [N II]/Halpha vs. [O III]/Hbeta. Active galaxies are further classified into Seyfert or LINER-like sources. We claim that a non-negligible fraction of galaxies classified as LINERs in the Sloan Digital Sky Survey are in fact ionized by hot post-AGB stars and white dwarfs.

  15. A service flow model for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Plum, Christian Edinger Munk; Pisinger, David; Sigurd, Mikkel M.

    2014-01-01

    . The model ensures strictly weekly frequencies of services, ensures that port-vessel draft capabilities are not violated, respects vessel capacities and the number of vessels available. The profit of the generated network is maximized, i.e. the revenue of flowed cargo subtracted operational costs...

  16. Why Do Hubs Tend to Be Essential in Protein Networks?

    Directory of Open Access Journals (Sweden)

    2006-06-01

    Full Text Available The protein-protein interaction (PPI network has a small number of highly connected protein nodes (known as hubs and many poorly connected nodes. Genome-wide studies show that deletion of a hub protein is more likely to be lethal than deletion of a non-hub protein, a phenomenon known as the centrality-lethality rule. This rule is widely believed to reflect the special importance of hubs in organizing the network, which in turn suggests the biological significance of network architectures, a key notion of systems biology. Despite the popularity of this explanation, the underlying cause of the centrality-lethality rule has never been critically examined. We here propose the concept of essential PPIs, which are PPIs that are indispensable for the survival or reproduction of an organism. Our network analysis suggests that the centrality-lethality rule is unrelated to the network architecture, but is explained by the simple fact that hubs have large numbers of PPIs, therefore high probabilities of engaging in essential PPIs. We estimate that ~ 3% of PPIs are essential in the yeast, accounting for ~ 43% of essential genes. As expected, essential PPIs are evolutionarily more conserved than nonessential PPIs. Considering the role of essential PPIs in determining gene essentiality, we find the yeast PPI network functionally more robust than random networks, yet far less robust than the potential optimum. These and other findings provide new perspectives on the biological relevance of network structure and robustness.

  17. Why do hubs tend to be essential in protein networks?

    Directory of Open Access Journals (Sweden)

    Xionglei He

    2006-06-01

    Full Text Available The protein-protein interaction (PPI network has a small number of highly connected protein nodes (known as hubs and many poorly connected nodes. Genome-wide studies show that deletion of a hub protein is more likely to be lethal than deletion of a non-hub protein, a phenomenon known as the centrality-lethality rule. This rule is widely believed to reflect the special importance of hubs in organizing the network, which in turn suggests the biological significance of network architectures, a key notion of systems biology. Despite the popularity of this explanation, the underlying cause of the centrality-lethality rule has never been critically examined. We here propose the concept of essential PPIs, which are PPIs that are indispensable for the survival or reproduction of an organism. Our network analysis suggests that the centrality-lethality rule is unrelated to the network architecture, but is explained by the simple fact that hubs have large numbers of PPIs, therefore high probabilities of engaging in essential PPIs. We estimate that approximately 3% of PPIs are essential in the yeast, accounting for approximately 43% of essential genes. As expected, essential PPIs are evolutionarily more conserved than nonessential PPIs. Considering the role of essential PPIs in determining gene essentiality, we find the yeast PPI network functionally more robust than random networks, yet far less robust than the potential optimum. These and other findings provide new perspectives on the biological relevance of network structure and robustness.

  18. Evaluation of microleakage in posterior nanocomposite restorations with adhesive liners

    Directory of Open Access Journals (Sweden)

    B Simi

    2011-01-01

    Full Text Available Aims and Objectives : To compare the microleakage in class II nanocomposite restorations without liner, with resin-modified glass ionomer liner and flowable composite liner. Materials and Methods : Thirty-six sound premolars extracted for orthodontic reasons were selected and randomly assigned into three groups of 12 teeth each (Group I, II and III. Class II cavities of specified dimensions were prepared with margins located in the enamel. Cavities in group I were lined with resin modified glass ionomer (GC Fuji II LC-Improved, group II were lined with flowable composite (Filtex Z350 Flowable Restorative and no liner was placed for cavities in group III. All the teeth were restored with nanocomposite (Z 350 Universal Restorative. The teeth were immersed in 0.5% methylene blue dye, sectioned mesiodistally and observed under stereomicroscope. Results : Group III showed maximum leakage compared to group I and II which was statistically significant. Microleakage was lesser in group lined with resin-modified glass ionomer as compared to flowable composite group but not statistically significant. Conclusions : Placement of liner beneath nanocomposite restoration results in significant reduction in microleakage. Both resin-modified and flowable composite liners under nanocomposite restorations result in comparable reduction of microleakage.

  19. Numerical studies of liners for magnetized target fusion (MTF)

    CERN Document Server

    Faehl, R J; Sheehey, P T; Lindemuth, I R

    1999-01-01

    Summary form only given. Magnetized target fusion (MTF) requires the fast compression of hot, dense plasmas by a conducting liner. We have used two-dimensional MHD calculations to study the electromagnetic implosion of metallic liners driven by realistic current waveforms. Parametric studies have indicated that the liner should reach velocities of 3-20 km/s, depending on the magnetic field configuration, and reach convergence ratios (initial radius divided by final radius) of at least 10. These parameters are accessible with large capacitor bank power supplies such as SHIVA or ATLAS, or with magnetic flux compression generators. One issue with the high currents that are required to implode the liner is that Ohmic heating will melt or vaporize the outer part of the liner. Calculations have shown that this is a realistic concern. We are currently addressing questions of liner instability and flux diffusion under MTF conditions. Another issue is that the magnetic fields needed to inhibit thermal losses to the wa...

  20. High Voltage Coaxial Vacuum Gap Breakdown for Pulsed Power Liners

    Science.gov (United States)

    Cordaro, Samuel; Bott-Suzuki, Simon; Caballero Bendixsen, Luis Sebastian

    2015-11-01

    The dynamics of Magnetized Liner Inertial Fusion (MagLIF)1, are presently under detailed study at Sandia National Laboratories. Alongside this, a comprehensive analysis of the influence of the specific liner design geometry in the MagLIF system on liner initiation is underway in the academic community. Recent work at UC San Diego utilizes a high voltage pulsed system (25kV, 150ns) to analyze the vacuum breakdown stage of liner implosion. Such experimental analyses are geared towards determining how the azimuthal symmetry of coaxial gap breakdown affect plasma initiation within the liner. The final aim of the experimental analysis is to assess to what scale symmetry remains important at high (MV) voltages. An analysis of the above will utilize plasma self-emission via optical MCP, current measurements, voltage measurements near the gap, exact location of breakdown via 2D b-dot probe triangulation, as well as measuring the evolution of the B-field along the length of the liner via b-dot array. Results will be discussed along with analytical calculations of breakdown mechanisms

  1. Cylindrical Liner Z-pinch Experiments on the MAGPIE Generator

    Science.gov (United States)

    Burdiak, Guy; Lebedev, Sergey V.; Harvey-Thompson, Adam J.; Swadling, George F.; Suzuki-Vidal, Francisco; Skidmore, Jonathan; Suttle, Lee; Khoory, Essa; Pickworth, Louisa; de Grouchy, Philip; Hall, Gareth N.; Bland, Simon N.; Weinwurm, Marcus; Chittenden, Jeremy P.

    2012-10-01

    Experimental data from gas-filled cylindrical liner z-pinch experiments is presented. The MAGPIE current (1.4 MA, 240 ns) is applied to a thin walled (80um) Al tube with a static gas-fill inside. The system is diagnosed axially using interferometry, optical streak photography and optical spectroscopy. We observe a series of cylindrically converging shock waves driven into the gas-fill from the inside liner surface. No bulk motion of the liner occurs. The timing of the shocks and their trajectories provide information on the shock launching mechanisms. This in turn allows a study of the response of the liner to the current pulse. Shock wave timing is compared to measurements of the liner resistance and optical images of the liner's outside surface. The system provides a useful, essentially 1D problem for testing MagLIF relevant MHD codes, particularly with regards to EOS, strength and resistivity models. This work may also be relevant to the study of shocks in astrophysical plasmas. The shocks launched into the gas radiatiate strongly; spatially resolved optical spectroscopy data and radial electron density profiles from interferometry images provide evidence for a radiative precursor ahead of the first shock. Instabilities are seen to develop in the downstream regions.

  2. A Conventional Liner Acoustic/Drag Interaction Benchmark Database

    Science.gov (United States)

    Howerton, Brian M.; Jones, Michael G.

    2017-01-01

    The aerodynamic drag of acoustic liners has become a significant topic in the design of such for aircraft noise applications. In order to evaluate the benefits of concepts designed to reduce liner drag, it is necessary to establish the baseline performance of liners employing the typical design features of conventional configurations. This paper details a set of experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of a number of perforate-over-honeycomb liner configurations at flow speeds of M=0.3 and 0.5. These conventional liners are investigated to determine their resistance factors using a static pressure drop approach. Comparison of the resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 Hz at source sound pressure levels of 140 and 150 dB. Educed impedance and attenuation spectra are used to determine the interaction between acoustic performance and drag.

  3. An environmental transfer hub for multimodal atom probe tomography.

    Science.gov (United States)

    Perea, Daniel E; Gerstl, Stephan S A; Chin, Jackson; Hirschi, Blake; Evans, James E

    2017-01-01

    Environmental control during transfer between instruments is required for samples sensitive to air or thermal exposure to prevent morphological or chemical changes prior to analysis. Atom probe tomography is a rapidly expanding technique for three-dimensional structural and chemical analysis, but commercial instruments remain limited to loading specimens under ambient conditions. In this study, we describe a multifunctional environmental transfer hub allowing controlled cryogenic or room-temperature transfer of specimens under atmospheric or vacuum pressure conditions between an atom probe and other instruments or reaction chambers. The utility of the environmental transfer hub is demonstrated through the acquisition of previously unavailable mass spectral analysis of an intact organic molecule made possible via controlled cryogenic transfer into the atom probe using the hub. The ability to prepare and transfer specimens in precise environments promises a means to access new science across many disciplines from untainted samples and allow downstream time-resolved in situ atom probe studies.

  4. Microfluidic hubs, systems, and methods for interface fluidic modules

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, Michael S; Claudnic, Mark R; Kim, Hanyoup; Patel, Kamlesh D; Renzi, Ronald F; Van De Vreugde, James L

    2015-01-27

    Embodiments of microfluidic hubs and systems are described that may be used to connect fluidic modules. A space between surfaces may be set by fixtures described herein. In some examples a fixture may set substrate-to-substrate spacing based on a distance between registration surfaces on which the respective substrates rest. Fluidic interfaces are described, including examples where fluid conduits (e.g. capillaries) extend into the fixture to the space between surfaces. Droplets of fluid may be introduced to and/or removed from microfluidic hubs described herein, and fluid actuators may be used to move droplets within the space between surfaces. Continuous flow modules may be integrated with the hubs in some examples.

  5. Mapping multiplex hubs in human functional brain networks

    Directory of Open Access Journals (Sweden)

    Alex Arenas

    2016-07-01

    Full Text Available Typical brain networks consist of many peripheral regions and a few highly centralones, i.e. hubs, playing key functional roles in cerebral inter-regional interactions. Studieshave shown that networks, obtained from the analysis of specific frequency components ofbrain activity, present peculiar architectures with unique profiles of region centrality. However,the identification of hubs in networks built from different frequency bands simultaneouslyis still a challenging problem, remaining largely unexplored. Here we identify eachfrequency component with one layer of a multiplex network and face this challenge by exploitingthe recent advances in the analysis of multiplex topologies. First, we show that eachfrequency band carries unique topological information, fundamental to accurately modelbrain functional networks. We then demonstrate that hubs in the multiplex network, in generaldifferent from those ones obtained after discarding or aggregating the measured signalsas usual, provide a more accurate map of brain’s most important functional regions, allowingto distinguish between healthy and schizophrenic populations better than conventionalnetwork approaches.

  6. A new method for improved hub height mean wind speed estimates using short-term hub height data

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, Matthew A.; Rogers, Anthony L.; Manwell, James F.; McGowan, Jon G. [Wind Energy Center, Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, 160 Governors Dr., Amherst, MA 01003 (United States)

    2010-10-15

    The estimation of the wind resource at the hub height of a wind turbine is one of the primary goals of site assessment. Because the measurement heights of meteorological towers (met towers) are typically significantly lower than turbine hub heights, a shear model is generally needed to extrapolate the measured wind resource at the lower measurement height to the hub height of the turbine. This paper presents methods for improving the estimate of the hub height wind resource from met tower data through the use of ground-based remote sensing devices. The methods leverage the two major advantages of these devices: their portability and their ability to measure at the wind turbine hub height. Specifically, the methods rely on augmenting the one year of met tower measurements with short-term measurements from a ground-based remote sensing device. The results indicate that the methods presented are capable of producing substantial improvements in the accuracy and uncertainty of shear extrapolation predictions. The results suggest that the typical site assessment process can be reevaluated, and alternative strategies that utilize ground-based remote sensing devices can be incorporated to significantly improve the process. (author)

  7. Ship construction and welding

    CERN Document Server

    Mandal, Nisith R

    2017-01-01

    This book addresses various aspects of ship construction, from ship types and construction materials, to welding technologies and accuracy control. The contents of the book are logically organized and divided into twenty-one chapters. The book covers structural arrangement with longitudinal and transverse framing systems based on the service load, and explains basic structural elements like hatch side girders, hatch end beams, stringers, etc. along with structural subassemblies like floors, bulkheads, inner bottom, decks and shells. It presents in detail double bottom construction, wing tanks & duct keels, fore & aft end structures, etc., together with necessary illustrations. The midship sections of various ship types are introduced, together with structural continuity and alignment in ship structures. With regard to construction materials, the book discusses steel, aluminum alloys and fiber reinforced composites. Various methods of steel material preparation are discussed, and plate cutting and form...

  8. Plastic Pollution from Ships

    OpenAIRE

    Čulin, Jelena; Bielić, Toni

    2016-01-01

    The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

  9. SHIPPING REQUESTS ON EDH

    CERN Multimedia

    Logistics Group

    2001-01-01

    Users are informed that as from 1 September 2001 all Shipping Requests must be made on EDH using the appropriate electronic form. The submission of user requests directly into EDH will help rationalise the activities of the Shipping Service (Import & Export), with requests being automatically forwarded to hierarchical supervisors thereby improving the processing speed and facilitating the follow-up. Thank you for your collaboration.

  10. SHIPPING REQUESTS ON EDH

    CERN Multimedia

    Logistics Group

    2001-01-01

    Users are informed that as from 1 September 2001 all Shipping Requests must be made on EDH using the appropriate electronic form. The submission of user requests directly into EDH will help rationalise the activities of the Shipping Service (Import & Export), with requests being automatically forwarded to hierarchical supervisors thereby improving the processing speed and facilitating the follow-up. Thank you for your collaboration.

  11. Ship bow waves

    Institute of Scientific and Technical Information of China (English)

    NOBLESSE Francis; DELHOMMEAU Gerard; LIU Hua; WAN De-cheng; YANG Chi

    2013-01-01

    The bow wave generated by a ship hull that advances at constant speed in calm water is considered.The bow wave only depends on the shape of the ship bow (not on the hull geometry aft of the bow wave).This basic property makes it possible to determine the bow waves generated by a canonical family of ship bows defined in terms of relatively few parameters.Fast ships with fine bows generate overturning bow waves that consist of detached thin sheets of water,which are mostly steady until they hit the main free surface and undergo turbulent breaking up and diffusion.However,slow ships with blunt bows create highly unsteady and turbulent breaking bow waves.These two alternative flow regimes are due to a nonlinear constraint related to the Bernoulli relation at the free surface.Recent results about the overturning and breaking bow wave regimes,and the boundary that divides these two basic flow regimes,are reviewed.Questions and conjectures about the energy of breaking ship bow waves,and free-surface effects on flow circulation,are also noted.

  12. Robust Energy Hub Management Using Information Gap Decision Theory

    DEFF Research Database (Denmark)

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    tools in order to deal with uncertainties and to provide reliable operating conditions. On a broader scale, an energy hub includes diverse energy sources for supplying both electrical load and heating/cooling demands with stochastic behaviors. Therefore, this paper utilizes the Information Decision Gap...... Theory (IGDT) to tackle this uncertainty as an efficient robust optimization tool with low complexity to ensure the optimal operation of the system according to the priorities of the decision maker entity. The proposed optimization framework is also implemented on a benchmark energy hub which includes...

  13. Variable volume combustor with center hub fuel staging

    Energy Technology Data Exchange (ETDEWEB)

    Ostebee, Heath Michael; McConnaughhay, Johnie Franklin; Stewart, Jason Thurman; Keener, Christopher Paul

    2016-08-23

    The present application and the resultant patent provide a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a center hub for providing the flow of fuel therethrough. The center hub may include a first supply circuit for a first micro-mixer fuel nozzle and a second supply circuit for a second micro-mixer fuel nozzle.

  14. Bus coordination holding control for transit hubs under APTS

    Institute of Scientific and Technical Information of China (English)

    TENG Jing; ZHAO Ming

    2009-01-01

    To increase the passenger transferring efficiency, the bus coordination holding control for transit hubs,hich is as an important dynamic dispatching method for improving the service level of transit hubs, was studied in the framework of bus coordination dispatching mode. Firstly, the bus coordination holding control flow was studied based on Advanced Public Transportation Systems (APTS) environment. Then a control model was presented to optimize the bus vehicle holding time, and a genetic algorithm was designed as the solving method. In the end, an example was given to illustrate the effectiveness of the control strategy and the algorithm.

  15. Geosynthetic clay liners - slope stability field study

    Energy Technology Data Exchange (ETDEWEB)

    Carson, D.A. [Environmental Protection Agency, Cincinnati, OH (United States); Daniel, D.E. [Univ. of Illinois, Urbana, IL (United States); Koerner, R.M. [Geosynthetic Research Institute, Philadelphia, PA (United States); Bonaparte, R. [GeoSyntec Consultants, Atlanta, GA (United States)

    1997-12-31

    A field research project was developed to examine the internal shear performance of geosynthetic clay liners (GCLs). Several combinations of cross sections were assembled using GCL materials that were available at the time of project initiation. The cross sections utilized were intended to simulate landfill cover applications. Thirteen (13) resulting test plots were constructed on two different slope angles, and each plot is instrumented for physical displacement and soil moisture characteristics. Test plots were constructed in a manner that dictated the shear plane in the clay portion of the GCL product. The project purpose is to assess field performance and to verify design parameters associated with the application of GCLs in waste containment applications. Interim research data shows that test slopes on 2H:1V show global deformation, but little internal shear evidence, and the 3H:1V slopes show little deformation at approximately 650 days. The research is ongoing, and this paper presents the most recent information available from the project.

  16. Outer Dynamics of Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisions with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the colliding structures....

  17. Outer Dynamics of Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose of these notes is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisons with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the collidi...

  18. SOME PROBLEMS ABOUT SHIP WAVES

    Institute of Scientific and Technical Information of China (English)

    Liu Min-jia

    2003-01-01

    Several problems about ship waves were discussed in the dissertation:(1) Transient ship waves from calmness to the generation of steady-state ship waves were described. (2) The procedure of the formation of the V-shaped steady-state ship waves were clearly shown, and the difference of ship waves on an inviscid fluid and on a viscous fluid was exmined. (3) With the Lighthill two-stage scheme, the algebraic expression for ship waves on a viscous fluid of finite depth was obtained.(4) Singularity on the two boundaries of the ship waves was treated.

  19. Accidents in nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Oelgaard, P.L. [Risoe National Lab., Roskilde (Denmark)]|[Technical Univ. of Denmark, Lyngby (Denmark)

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

  20. Robot mother ship design

    Science.gov (United States)

    Budulas, Peter P.; Young, Stuart H.; Emmerman, Philip J.

    2000-07-01

    Small physical agents will be ubiquitous on the battlefield of the 21st century, principally to lower the exposure to harm of our ground forces. Teams of small collaborating physical agents conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA); chemical and biological agent detection, logistics, sentry; and communications relay will have advanced sensor and mobility characteristics. The mother ship much effectively deliver/retrieve, service, and control these robots as well as fuse the information gathered by these highly mobile robot teams. The mother ship concept presented in this paper includes the case where the mother ship is itself a robot or a manned system. The mother ship must have long-range mobility to deploy the small, highly maneuverable agents that will operate in urban environments and more localized areas, and act as a logistics base for the robot teams. The mother ship must also establish a robust communications network between the agents and is an up-link point for disseminating the intelligence gathered by the smaller agents; and, because of its global knowledge, provides the high-level information fusion, control and planning for the collaborative physical agents. Additionally, the mother ship incorporates battlefield visualization, information fusion, and multi-resolution analysis, and intelligent software agent technology, to support mission planning and execution. This paper discusses on going research at the U.S. Army Research Laboratory that supports the development of a robot mother ship. This research includes docking, battlefield visualization, intelligent software agents, adaptive communications, information fusion, and multi- modal human computer interaction.

  1. Portable Desktop Apps with GitHub Electron

    CERN Document Server

    CERN. Geneva

    2016-01-01

    Wouldn't it be nice if you could develop applications that work everywhere, regardless of Operating System or Platform? Even better, what if you could employ the same front-end technologies you use for your web/mobile apps? Meet GitHub Electron.

  2. The evolution of the MasAgro hubs

    NARCIS (Netherlands)

    Camacho-Villa, Tania Carolina; Almekinders, Conny; Hellin, Jon; Martinez-Cruz, Tania Eulalia; Rendon-Medel, Roberto; Guevara-Hernández, Francisco; Beuchelt, Tina D.; Govaerts, Bram

    2016-01-01

    Purpose: Little is known about effective ways to operationalize agricultural innovation processes. We use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how innov

  3. Native Avatars, Online Hubs, and Urban Indian Literature

    Science.gov (United States)

    Estrada, Gabriel S.

    2011-01-01

    Teaching American Indian literature with online resources can help diverse urban Indian and multicultural students connect with American Indian cultures, histories, and Nations. This online-enriched pedagogy adopts Susan Lobo's sense of the city as an "urban hub," or activist community center, an urban area linked to reservations in which Native…

  4. Fatigue Analysis of Casted Hubs in Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Nielsen, Søren R.K.; Sørensen, Steffen

    2002-01-01

    The hub of a wind turbine rotor is excited by time-varying forces and moments from the blades caused by extemal dynamic loads such as wind loading and aeroelastic effects. The paper describes how reliability-based fatigue analysis can be made based on SN-curves and how reliability-based inspectio...

  5. Functional Connectivity Hubs and Networks in the Awake Marmoset Brain

    Directory of Open Access Journals (Sweden)

    Annabelle Marie Belcher

    2016-03-01

    Full Text Available In combination with advances in analytical methods, resting-state fMRI is allowing unprecedented access to achieve a better understanding of the network organization of the brain. Increasing evidence suggests that this architecture may incorporate highly functionally connected nodes, or hubs, and we have recently proposed local functional connectivity density (lFCD mapping to identify highly-connected nodes in the human brain. Here we imaged awake nonhuman primates to test whether, like the human brain, the marmoset brain contains functional connectivity hubs. Ten adult common marmosets (Callithrix jacchus were acclimated to mild, comfortable restraint using individualized helmets. Following restraint training, resting BOLD data were acquired during eight consecutive 10 min scans for each subject. lFCD revealed prominent cortical and subcortical hubs of connectivity across the marmoset brain; specifically, in primary and secondary visual cortices (V1/V2, higher-order visual association areas (A19M/V6[DM], posterior parietal and posterior cingulate areas (PGM and A23b/A31, thalamus, dorsal and ventral striatal areas (caudate, putamen, lateral septal nucleus, and anterior cingulate cortex (A24a. lFCD hubs were highly connected to widespread areas of the brain, and further revealed significant network-network interactions. These data provide a baseline platform for future investigations in a nonhuman primate model of the brain’s network topology.

  6. The evolution of the MasAgro hubs

    NARCIS (Netherlands)

    Camacho-Villa, Tania Carolina; Almekinders, Conny; Hellin, Jon; Martinez-Cruz, Tania Eulalia; Rendon-Medel, Roberto; Guevara-Hernández, Francisco; Beuchelt, Tina D.; Govaerts, Bram

    2016-01-01

    Purpose: Little is known about effective ways to operationalize agricultural innovation processes. We use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how

  7. DAVINC3I: moving towards responsive hub network designs

    NARCIS (Netherlands)

    Ossevoort, R.; Keizer, de M.; Vorst, van der J.G.A.J.; Wenink, E.

    2013-01-01

    The Dutch floricultural sector is generally appreciated for its world leadership; the Netherlands is the flower trading hub for the European market. There are two trends affecting this position. First, virtualisation makes trade flows relatively footloose and flexible. Moreover, it enables the use o

  8. Discovering Authorities and Hubs in Different Topological Web Graph Structures.

    Science.gov (United States)

    Meghabghab, George

    2002-01-01

    Discussion of citation analysis on the Web considers Web hyperlinks as a source to analyze citations. Topics include basic graph theory applied to Web pages, including matrices, linear algebra, and Web topology; and hubs and authorities, including a search technique called HITS (Hyperlink Induced Topic Search). (Author/LRW)

  9. DAVINC3I: moving towards responsive hub network designs

    NARCIS (Netherlands)

    Ossevoort, R.; Keizer, de M.; Vorst, van der J.G.A.J.; Wenink, E.

    2013-01-01

    The Dutch floricultural sector is generally appreciated for its world leadership; the Netherlands is the flower trading hub for the European market. There are two trends affecting this position. First, virtualisation makes trade flows relatively footloose and flexible. Moreover, it enables the use o

  10. Interaction of railway and marine transport (Murmansk Transport Hub

    Directory of Open Access Journals (Sweden)

    Sokolov A.A.

    2015-03-01

    Full Text Available The classification of problems of interaction between water (marine and railway transport on the example of the Murmansk Transport Hub has been presented; some prospects for the development of technology for interaction with the logistics of transportation of general cargo in the Murmansk Commercial Seaport, Murmansk Marine Fishing Port, and oil terminals of the Kola Bay have been shown

  11. The Urban Food Hubs Solution: Building Capacity in Urban Communities

    Science.gov (United States)

    O'Hara, Sabine

    2017-01-01

    Access to affordable fresh food is an ongoing challenge for underserved urban neighborhoods across the United States. Several are designated food deserts with no access to a full-service grocery store within a one-mile radius. The Urban Food Hubs of the College of Agriculture, Urban Sustainability, and Environmental Sciences (CAUSES) of the…

  12. Advanced Computational and Experimental Techniques for Nacelle Liner Performance Evaluation

    Science.gov (United States)

    Gerhold, Carl H.; Jones, Michael G.; Brown, Martha C.; Nark, Douglas

    2009-01-01

    The Curved Duct Test Rig (CDTR) has been developed to investigate sound propagation through a duct of size comparable to the aft bypass duct of typical aircraft engines. The axial dimension of the bypass duct is often curved and this geometric characteristic is captured in the CDTR. The semiannular bypass duct is simulated by a rectangular test section in which the height corresponds to the circumferential dimension and the width corresponds to the radial dimension. The liner samples are perforate over honeycomb core and are installed on the side walls of the test section. The top and bottom surfaces of the test section are acoustically rigid to simulate a hard wall bifurcation or pylon. A unique feature of the CDTR is the control system that generates sound incident on the liner test section in specific modes. Uniform air flow, at ambient temperature and flow speed Mach 0.275, is introduced through the duct. Experiments to investigate configuration effects such as curvature along the flow path on the acoustic performance of a sample liner are performed in the CDTR and reported in this paper. Combinations of treated and acoustically rigid side walls are investigated. The scattering of modes of the incident wave, both by the curvature and by the asymmetry of wall treatment, is demonstrated in the experimental results. The effect that mode scattering has on total acoustic effectiveness of the liner treatment is also shown. Comparisons of measured liner attenuation with numerical results predicted by an analytic model based on the parabolic approximation to the convected Helmholtz equation are reported. The spectra of attenuation produced by the analytic model are similar to experimental results for both walls treated, straight and curved flow path, with plane wave and higher order modes incident. The numerical model is used to define the optimized resistance and reactance of a liner that significantly improves liner attenuation in the frequency range 1900-2400 Hz. A

  13. Seismic stability and permanent displacement of landfill along liners

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The three-part wedge limit equilibrium method for seismic stability analysis of the landfill along liners is presented. The approximate solutions of the factor of safety and the yield acceleration coefficient are obtained. Parametric studies show that the interface strength of liners, the shear strength of waste and the height of retaining wall can influence the seismic stability of landfill along liners. The density and the shear wave velocity of the field waste are obtained by the borehole investigation and the spectral analysis of surface wave (SASW), respectively. The strain-dependent shear modulus and damping ratio of the artifical waste are obtained by the moderate-scale dynamic triaxial tests. The onedimensional (1D) equivalent linear dynamic response analysis is used to calculate the horizontal equivalent seismic coefficient-time history of the sliding landfill during earthquake. The seismic permanent displacement of the landfill along liners with different site conditons and heights is evaluated by the Newmark method. The catculated results show that ratio of ky /kmax, site conditions, the amplitude and frequency content of the bedrock motion can affect the seismic permanent displacement of the landfill along liners in some degree. Finally, the seismic stability and permanent displacements of three expanded configurations of a certain landfill case are analyzed.

  14. Detection of compact ultraviolet nuclear emission in liner galaxies

    CERN Document Server

    Maoz, D; Ho, L C; Rix, H W; Bahcall, J N; Schneider, D P; Macchetto, F D; Dan Maoz; Alexei V Filippenko; Luis C Ho; Hans-Walter Rix; John N Bahcall; Donald P Schneider

    1994-01-01

    Low-ionization nuclear emission-line regions (LINERs), which exist in a large fraction of galaxies, may be the least luminous manifestation of quasar activity. The nature of LINERs has, however, remained controversial because an AGN-like nonstellar continuum source has not been directly observed in them. We report the detection of bright, unresolved (FWHM \\ltorder 0.1'') point sources of UV (\\sim 2300 \\AA) emission in the nuclei of nine nearby galaxies from a complete sample of 110 nearby galaxies imaged with {\\it HST}. Ground-based optical spectroscopy reveals that five of the nuclei are LINERs, three are starburst nuclei, and one is a Seyfert nucleus. The observed UV flux in each of the five LINERs implies an ionizing flux that is sufficient to account for the observed emission lines through photoionization. The detection of a strong UV continuum in the LINERs argues against shock excitation as the source of the observed emission lines, and supports the idea that photoionization excites the lines in at leas...

  15. Seismic stability and permanent displacement of landfill along liners

    Institute of Scientific and Technical Information of China (English)

    CHEN YunMin; GAO Deng; ZHU Bin; CHEN RenPeng

    2008-01-01

    The three-part wedge limit equilibrium method for seismic stability analysis of the landfill along liners is presented. The approximate solutions of the factor of safety and the yield acceleration coefficient are obtained. Parametric studies show that the interface strength of liners, the shear strength of waste and the height of retaining wall can influence the seismic stability of landfill along liners. The density and the shear wave velocity of the field waste are obtained by the borehole investigation and the spectral analysis of surface wave (SASW), respectively. The strain-dependent shear modulus and damping ratio of the artifical waste are obtained by the moderate-scale dynamic triaxial tests. The one- dimensional (1D) equivalent linear dynamic response analysis is used to calculate the horizontal equivalent seismic coefficient-time history of the sliding landfill during earthquake. The seismic permanent displacement of the landfill along liners with different site conditons and heights is evaluated by the Newmark method. The catculated results show that ratio of ky/kmax, site conditions, the amplitude and frequency content of the bedrock motion can affect the seismic permanent displacement of the landfill along liners in some degree. Finally, the seismic stability and permanent displacements of three expanded configurations of a certain landfill case are analyzed.

  16. Boundary layer effects on liners for aircraft engines

    Science.gov (United States)

    Gabard, Gwénaël

    2016-10-01

    The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite difference method. The parameters are representative of the flow conditions, liners and sound fields found in current turbofan engines. Both the intake and bypass ducts are considered. Results show that there is a complex interplay between the boundary layer thickness, the direction of propagation and the liner impedance and that the boundary layer can have a strong impact on liner performance for typical configurations (including changes of the order of 30 dB on the attenuation of modes associated with tonal fan noise). A modified impedance condition including the effect of a small but finite boundary layer thickness is considered and compared to the standard Myers condition based on an infinitely thin boundary layer. We show how this impedance condition can be implemented in a mode calculation method by introducing auxiliary variables. This condition is able to capture the trends associated with the boundary layer effects and in most cases provides improved predictions of liner performance.

  17. The Structure of Narrow-Line Region in LINERs

    Institute of Scientific and Technical Information of China (English)

    Hai-Feng Dai; Ting-Gui Wang

    2008-01-01

    Low-ionization nuclear emission regions (LINERs) are present in a large fraction of local galaxies, while their connection to the more luminous active galactic nuclei (AGN) remains elusive. We analyze the narrow band images obtained by the Hubble Space Telescope (HST) in Hα+[NⅡ] and/or [OⅢ] band for 23 LINERs and low luminosity Seyfert galaxies in the sample of the Palomar Optical Spectroscopic Survey of nearby galaxies in an attempt to resolve the structure of Narrow Emission Line Regions (NLRs) of these objects. In all cases, NLRs are well resolved and their morphology differs from object to object. Clumps, linear structure, spiral arms or a ring are detected in a large fraction of the objects, while there is no significant difference between Seyfert galaxies and LINERs. We find that the NLR size and the narrow line luminosity are strongly correlated for both LINERs and low luminosity Seyfert galaxies, and that the size of Hα+[NⅡ] emission line region scales with Hα luminosity as RNLR∞L0.4±0.06Hα, consistent with an extension of the NLR size-luminosity relation defined for luminous Seyfert galaxies and quasars, to two orders of magnitude lower in luminosity and to lower activity levels. Our results suggest that NLRs in LINERs are similar to those of Seyfert galaxies, and they are powered by the central active galactic nucleus.

  18. Multiple Hub Network Choice in the Liberalized European Market

    Science.gov (United States)

    Berechman, Joseph; deWit, Jaap

    1997-01-01

    A key question that so far has received relatively little attention in the germane literature is that of the changes at various airports as a result of the EU liberalization policies. That is, presently, most major European airports still benefit from the so-called home-carrier phenomenon where the country's publicly or semi-publicly owned carrier uses the country's main airport as its gateway hub and, consequently, the home-carrier is also the principal user of this airport (in terms of proportion of total aircraft movements, number of passengers transported, connections, slots ownership, etc.). The country's main airport has substantially benefited from these monopoly conditions of airline captivity, strongly determined by the bilateral system of international air transport regulation. Therefore, European major airports were used to operate in essentially different markets, compared to the increasingly competitive markets of their home based carriers. This partly explains relative stability of transport volumes and financial results of European major airports compared to the relatively volatile financial results of most European national airlines. However, the liberalization of European aviation is likely to change this situation. Market access is open now to all community carriers, i.e. carriers with majority ownership and effective control in the hands of EU citizens. Ticket prices are free, governments can only intervene in case of dumping or excessive pricing. A community airline can choose its seat in any of the 15 member states. Licensing procedures are harmonized between member states. In the last few months community carriers have had unrestricted route access within the EU. Most probably this development will be extended to countries inside and outside Europe. Last year the European Commission got the mandate to start negotiations with 10 other European countries. In the meantime the EC has also started negotiations with the USA on so-called soft rights

  19. Beryllium liner implosion experiments on the Z accelerator in preparation for Magnetized Liner Inertial Fusion (MagLIF)*

    Science.gov (United States)

    McBride, Ryan D.

    2012-10-01

    Magnetized Liner Inertial Fusion (MagLIF) [1] is a concept that involves using a pulsed electrical current to implode an initially-solid, cylindrical metal tube (liner) filled with preheated and magnetized fusion fuel. One- and two-dimensional simulations predict that if sufficient liner integrity can be maintained throughout the implosion, then significant fusion yield (>100 kJ) is possible on the 25-MA, 100-ns Z accelerator. The greatest threat to the liner integrity is the Magneto-Rayleigh-Taylor (MRT) instability, which first develops on the outer liner surface, and then works its way inward toward the inner surface throughout the implosion. Two-dimensional simulations predict that a thick liner, with Router/δR=6, should be robust enough to keep the MRT instability from overly disrupting the fusion burn at stagnation. This talk will present the first experiments designed to study a thick, MagLIF-relevant liner implosion through to stagnation on Z [2]. The use of beryllium for the liner material enabled us to obtain penetrating monochromatic (6151±0.5 eV) radiographs that reveal information about the entire volume of the imploding liner. This talk will also discuss experiments that investigated Z's pulse-shaping capabilities to either shock- or shocklessly-compress the imploding liners [3], as well as our most recent experiments that used 2-micron-thick aluminum sleeves to provide high-contrast tracers for the positions and states of the inner surfaces of the imploding beryllium liners. The radiography data to be presented provide stringent constraints on the simulation tools used by the broader high energy density physics and inertial confinement fusion communities, where quantitative areal density measurements, particularly of convergent fusion targets, are relatively scarce. We will also present power-flow tests of the MagLIF load hardware as well as new micro-B-dot measurements of the azimuthal drive magnetic field that penetrates the initially vacuum

  20. In-situ studies on the performance of landfill caps (compacted soil liners, geomembranes, geosynthetic clay liners, capillary barriers)

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, S. [IGB - Ingenieurbuero fuer Grundbau, Hamburg (Germany)

    1997-12-31

    Since 1986 different types of landfill covers have been studied in-situ on the Georgswerder landfill in Hamburg, Germany. Water balance data are available for eight years. The performance of different carriers has been measured by collecting the leakage on areas ranging from 100 m{sup 2} to 500 m{sup 2}. Composite liners with geomembranes performed best, showing no leakage. An extended capillary barrier also performed well. The performance of compacted soil liners, however, decreased severely within five years due to desiccation, shrinkage and plant root penetration (liner leakage now ranging from 150 mm/a to 200 mm/a). About 50 % of the water that reaches the surface of the liner is leaking through it. The maximum leakage rates have increased from 2 x 10{sup -10} m{sup 3} m{sup -2} s{sup -1} to 4 x 10{sup -8} m{sup 3} m{sup -2} s{sup -1}. Two types of geosynthetic clay liners (GCL) have been tested for two years now with disappointing results. The GCL desiccated during the first dry summer of the study. High percolation rates through the GCL were measured during the following winter (45 mm resp. 63 mm in four months). Wetting of the GCL did not significantly reduce the percolation rates.

  1. A semi-analytic model of magnetized liner inertial fusion

    CERN Document Server

    McBride, Ryan D

    2015-01-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized alpha-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original Ma...

  2. Acoustic Liner Drag: Measurements on Novel Facesheet Perforate Geometries

    Science.gov (United States)

    Howerton, Brian M.; Jones, Michael G.

    2016-01-01

    Interest in characterization of the aerodynamic drag of acoustic liners has increased in the past several years. This paper details experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of several perforate-over-honeycomb liner configurations at flow speeds of centerline flow Mach number equals 0.3 and 0.5. Various perforate geometries and orientations are investigated to determine their resistance factors using a static pressure drop approach. Comparison of these resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 hertz at source sound pressure levels of 140 and 150 decibels. Educed impedance and attenuation spectra are used to determine the impact of variations in perforate geometry on acoustic performance.

  3. Transmissivity evolution through interface of composite liners under applied constraint.

    Science.gov (United States)

    Diagne, M

    2011-08-01

    In landfill liners, geomembranes have defects that constitute preferential passages of leachate from rainwater percolation. Non-woven geotextiles are widely used in wastelandfills as materials having the functions of protection, separation, filtration and drainage. This study seeks to select geotextiles through an investigation conducted among landfill operators who commonly arise a geotextile in the geomembrane-clay interface to facilitate geomembrane welding and to prevent its puncture by angular materials. It also attempts to find out the influence of geotextile in a decimetric transmissivity cell size under 50 kPa stress and smooth ground surface. The results show that the transmissivity in composite liner interface is almost the same as the one calculated with the European standard EN ISO 12958. Transmissivity depends on the mechanical stress applied to the bottom liner, on the geotextile type in the interface and on the ground surface.

  4. Predrilled liner / barefoot completions in horizontal sour gas wells

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, M.W. [Mobil Erdgas-Erdoel GmbH, Celle (Germany)

    1999-09-01

    When selecting the completion type of a horizontal well, all relevant production and reservoir engineering aspects have to be taken into consideration to ensure safe and optimised long-term production. Especially in the case of sour gas wells, which require corrosion-resistant and expensive alloys, the technical/economic need to run a liner in the horizontal section is often discussed. This paper compares the preinvestment for a 'predrilled liner' with the cost of downhole operations which may become necessary in a 'barefoot completion'. These calculated 'risked savings' - as a function of the horizontal length - lead to a break-even point which is intended to assist in the decision to run a liner in sour gas wells or not. (orig.)

  5. Optimization of a Ranchero driven high energy liner driver system

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, Walter L [Los Alamos National Laboratory; Kaul, Ann [Los Alamos National Laboratory; Rousculp, Chris L [Los Alamos National Laboratory; Watt, Robert G [Los Alamos National Laboratory

    2008-01-01

    An experimental series is planned to implode a dense heavy liner to a velocity in excess of 1 cm/microsecond (10 mm/microsecond) using a RANCHERO coaxial explosive flux compression generator. The goal of this study is to choose the liner mass and starting radius that will deliver the greatest amount of kinetic energy to a target at 1 cm final radius. In this study we used the 1D-MHD simulation code RA YEN to search for the proper initial conditions. The results will be used as a starting point for 2-D simulations and preliminary designs for the first experiments planned in the 2009/2010 time frame. The preliminary results indicate that a liner velocity of 1.25 cm/microsecond and a kinetic energy of greater than 4 megajoules may be possible.

  6. Non-contact optical three dimensional liner metrology

    CERN Document Server

    Sebring, R J; Salazar, M A

    2001-01-01

    Summary form only given, as follows. We optically captured the "as- built" geometry of NTLX cylindrical liners for Shiva Star using an ultra-precision ranging laser. We subsequently verified the resulting digitized geometry against the 3D CAD model of the part. The results confirmed that the liner contours are within designed tolerances but revealed subtle fabrication artifacts that would typically go undetected. These features included centimeters long waviness and saddle and bulge regions of 1 micron or less in magnitude. The laser technology typically provided 10 micron spatial resolution with 112 nanometer ranging precision. Atlas liners in the future may have to be diamond turned and will have the centimeter wavelength and 100 angstrom amplitude requirements. The advantages of using laser technology is 1) it avoids surface damage that may occur with conventional contact probes and 2) dramatically improves spatial resolution over CMM, LVDT, capacitance and inductance type probes. Our work is the result of...

  7. Beam-Wall interaction in the LHC liner

    CERN Document Server

    Mostacci, A

    2001-01-01

    The beam pipe foreseen for the LHC is rather unconventional. To shield the cold bore of the magnets from the synchrotron radiation emitted by protons at 7 TeV, a beam screen (the so called "liner") has been introduced practically along all the machine. The present design of the liner is a compromise among beam stability issues, vacuum requirements, heat load on the cold bore, electron cloud effects and mechanical constraints. Three main potential sources of beam energy loss in the actual LHC liner are addressed, namely the interaction with the pumping holes, the (sawtooth) surface corrugation and the effect of an azimuthally inhomogeneous metallic beam pipe modelling the high resistivity of the welding. The losses are estimated through a detailed electromagnetic analysis (by means of standard theories) seeking for analytical expressions of electromagnetic fields and/or coupling impedance. An analytical (or semi-analytical) approach is considered for each problem, to better understand the relevant parameters t...

  8. Shipping emissions in ports

    OpenAIRE

    2014-01-01

    Shipping emissions in ports are substantial, accounting for 18 million tonnes of CO2 emissions, 0.4 million tonnes of NOx, 0.2 million of SOx and 0.03 million tonnes of PM10 in 2011. Around 85% of emissions come from containerships and tankers. Containerships have short port stays, but high emissions during these stays. Most of CO2 emissions in ports from shipping are in Asia and Europe (58%), but this share is low compared to their share of port calls (70%). European ports have much less emi...

  9. Europe's Southeastern Gateway: Responding to Rapidly Changing Patterns of World Shipping. The University's Role

    Directory of Open Access Journals (Sweden)

    Roger E. HAMLIN

    2012-12-01

    Full Text Available World trade and transportation are changing dramatically. Energy prices and transport sustainability concerns are reinvigorating ocean freighter shipping. An ever-increasing portion of trade is in containers, and container ships are getting larger quickly. Many ports, nations and continents are not keeping up with ship size increases putting them at a trade disadvantage. Major canals and seaways must also upgrade or be rendered obsolete, causing a change in the pattern of world trade. Ports have to do more than expand vessel size limits. Port regions must also invest in infrastructure that improves multi-modal access to the port and augments hand-off of containers to smaller seaway ships, trains and trucks. With heightened security and evolving emphasis on flexible and efficient logistics, ports must become high-tech logistics hubs with improved real-time data about port throughput. Constanţa, Romania provides an example of an attempt to respond to this rapid change. Near the Danube Delta, on the Black Sea, Constanţa offers a potential southeastern gateway to Europe for the Black Sea, the Eastern Mediterranean and beyond. Ships from Asia, entering via the Suez Canal can easily access Constanţa, and thus save more than ten days of shipping time for destinations in southeastern Europe compared to shipping through Rotterdam or Hamburg. But Constanţa needs to make all the improvements mentioned above. Universities have several roles in this endeavor, including identifying and forecasting trends, providing the technical knowledge to develop high-tech logistics hubs, pursing publicprivate partnerships for infrastructure development and offering training.

  10. Predicting Ship Fuel Consumption: Update.

    Science.gov (United States)

    1996-07-01

    ship propulsion fuel consumption as a function of ship speed for U.S. Navy combatant and auxiliary ships. Prediction is based on fitting an analytic function to published ship class speed-fuel use data using nonlinear regression. The form of the analytic function fitted is motivated by the literature on ship powering and resistance. The report discusses data sources and data issues, and the impact of ship propulsion plant configuration on fuel use. The regression coefficients of the exponential function fitted, tabular numerical comparison of

  11. Optimization of Microphone Locations for Acoustic Liner Impedance Eduction

    Science.gov (United States)

    Jones, M. G.; Watson, W. R.; June, J. C.

    2015-01-01

    Two impedance eduction methods are explored for use with data acquired in the NASA Langley Grazing Flow Impedance Tube. The first is an indirect method based on the convected Helmholtz equation, and the second is a direct method based on the Kumaresan and Tufts algorithm. Synthesized no-flow data, with random jitter to represent measurement error, are used to evaluate a number of possible microphone locations. Statistical approaches are used to evaluate the suitability of each set of microphone locations. Given the computational resources required, small sample statistics are employed for the indirect method. Since the direct method is much less computationally intensive, a Monte Carlo approach is employed to gather its statistics. A comparison of results achieved with full and reduced sets of microphone locations is used to determine which sets of microphone locations are acceptable. For the indirect method, each array that includes microphones in all three regions (upstream and downstream hard wall sections, and liner test section) provides acceptable results, even when as few as eight microphones are employed. The best arrays employ microphones well away from the leading and trailing edges of the liner. The direct method is constrained to use microphones opposite the liner. Although a number of arrays are acceptable, the optimum set employs 14 microphones positioned well away from the leading and trailing edges of the liner. The selected sets of microphone locations are also evaluated with data measured for ceramic tubular and perforate-over-honeycomb liners at three flow conditions (Mach 0.0, 0.3, and 0.5). They compare favorably with results attained using all 53 microphone locations. Although different optimum microphone locations are selected for the two impedance eduction methods, there is significant overlap. Thus, the union of these two microphone arrays is preferred, as it supports usage of both methods. This array contains 3 microphones in the upstream

  12. Constraining the Accretion Mode in LINER 1.9s

    Science.gov (United States)

    Sabra, Bassem; Der Sahaguian, Elias; Badr, Elie

    2016-01-01

    The accretion mode and the dominant power source in low-ionization nuclear emission-line regions (LINERs), a class of active galactic nuclei (AGN), are still elusive. We focus on a sample of 22 LINER 1.9s (Ho et al. 1997), a subclass of LINERs that show broad Halpha lines, a signature of blackhole-powered accretion, to test the hypothesis that the ionizing continuum emitted by a radiatively inefficient accretion flow (RIAF) could lead to the LINER ultraviolet (UV) emission-line ratios. Optical line-ratio diagrams are a weak diagnostic tool in distinguishing between possible power sources (Sabra et al. 2003). We search the Mikulski Archive for Space Telescopes (MAST) for UV spectra of the objects in the above sample and also perform photoionization simulations using CLOUDY (Ferland et al. 2013). Unfortunately, only one object (NGC 1052; Gabel et al. 2000) of the 22 LINER 1.9s has UV spectra that cover many emission lines; the rest of the objects either do not have any UV spectra, the spectral coverage is in-adequate, or the spectra have very low signal-to-noise ratios. Our photoionization simulations set up two identical grids of clouds with a range of densities and ionization parameters. We illuminate one grid with radiation emitted by a thin accretion disk (AD) and we illuminate the other grid with radiation from a RIAF. We overplot the UV emission-line ratio predictions for AD and RIAF illumination, together with the available line ratios for NGC 1052. Initial results show that UV lines could be used as diagnostics for the accretion mode in AGN. More UV spectral coverage of LINER 1.9s is needed in order to more fully utilize the diagnostic powers of UV emission line ratios.

  13. Novel Processing of 81-mm Cu Shaped Charge Liners

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, A; Korzekwa, D

    2002-01-16

    A seven-step procedure was developed for producing shaped charge liner blanks by back extrusion at liquid nitrogen temperatures. Starting with a 38.1-mm diameter, 101.6-mm long cylinder at 77K, three forging steps with a flat-top die are required to produce the solid cone while maintaining low temperature. The solid cone is forged in four individual back extrusions at 77K to produce the rough liner blank. This procedure is capable of being run in batch processes to improve the time efficiency.

  14. Rational design approach for landfill liner protective soil cover

    Energy Technology Data Exchange (ETDEWEB)

    Ruetten, M.G. [STS Consultants Ltd., Green Bay, WI (United States); Bandi, S.R. [Rust Environment & Infrastructure, Livonia, MI (United States); Reddy, K.R. [Univ. of Illinois, Chicago, IL (United States)

    1995-12-31

    This paper presents a rational approach for designing protective soil cover for landfill geomembrane liners in order to prevent damage to the liners. The present practice involves using a combination of geotextile and soil layer as protective cover. The geotextile is placed directly over the geomembrane and then a protective soil is placed on the geotextile. The protective soil layer generally consists of a free-draining granular soil which also serves as a drainage layer for the leachate collection and removal system. The degree of protection offered to the geomembrane depends on the type of geotextile, and the composition and thickness of the protective soil used.

  15. Literature review of the possible advantages of silicon liner socket use in trans-tibial prostheses

    NARCIS (Netherlands)

    Baars, ECT; Geertzen, JHB

    2005-01-01

    The silicon liner socket has been used in the trans-tibial prosthesis since the 1980s. Silicon liner sockets are sleeves of silicon material that are rolled onto the stump and fix the prosthesis to it. The producers of the liners propagate many advantages in their use i.e. better suspension of the p

  16. Mechanics of Ship Grounding

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    In these notes first a simplified mathematical model is presented for analysis of ship hull loading due to grounding on relatively hard and plane sand, clay or rock sea bottoms. In a second section a more rational calculation model is described for the sea bed soil reaction forces on the sea bottom...

  17. Moving Sustainable Shipping Forward

    NARCIS (Netherlands)

    Leeuwen, van J.; Koppen, van C.S.A.

    2016-01-01

    The International Maritime Organization (IMO) is considering adopting marketbased mechanisms (MBMs) to reduce fuel consumption by commercial shipping. This paper explores the potential effectiveness of these MBMs. How companies respond to economic stimuli generated by MBMs depends on the kind of env

  18. Littoral Combat Ship (LCS)

    Science.gov (United States)

    2015-12-01

    Defense Switched Network EMD - Engineering and Manufacturing Development EVM - Earned Value Management FOC - Full Operational Capability FMS - Foreign...responses to small boat threats, mine laying and quiet diesel submarines. LCS employment of networked sensors for Intelligence, Surveillance, and...Flight 0 ships in addition to the program development, test and evaluation, training development, and sustained engineering for both LCS and Frigate

  19. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.

  20. Moving Sustainable Shipping Forward

    NARCIS (Netherlands)

    Leeuwen, van J.; Koppen, van C.S.A.

    2016-01-01

    The International Maritime Organization (IMO) is considering adopting marketbased mechanisms (MBMs) to reduce fuel consumption by commercial shipping. This paper explores the potential effectiveness of these MBMs. How companies respond to economic stimuli generated by MBMs depends on the kind of

  1. Ship Observations - VOS and Navy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Combination of Voluntary Observing Ship (VOS) and US Navy Ship weather observations. Obs generally taken 2-4 times daily at 00, 06, 12, and 18z.

  2. Travelers' Health: Cruise Ship Travel

    Science.gov (United States)

    ... Water Disinfection Infographics for Travelers MERS Health Advisory poster Food and Water: What's Safer Health Advisory: MERS ... cruise ships can vary widely depending on ship size, itinerary, length of cruise, and passenger demographics. Generally, ...

  3. Ageing of ships, LPG tankers

    OpenAIRE

    Ask, Martin

    2015-01-01

    During the last decades there have been several major ship accidents, and it is believed that old ships are more unsafe than newer ships. To get a better understanding of this phenomenon the thesis is investigating different issues with ship ageing. This thesis consists of a general description of the most important ageing issues, and the condition of sea water ballast tanks is identified as one of the most critical issue regarded to ageing on LPG-tankers. This investigation consists of...

  4. Revisiting date and party hubs: novel approaches to role assignment in protein interaction networks.

    Directory of Open Access Journals (Sweden)

    Sumeet Agarwal

    2010-06-01

    Full Text Available The idea of "date" and "party" hubs has been influential in the study of protein-protein interaction networks. Date hubs display low co-expression with their partners, whilst party hubs have high co-expression. It was proposed that party hubs are local coordinators whereas date hubs are global connectors. Here, we show that the reported importance of date hubs to network connectivity can in fact be attributed to a tiny subset of them. Crucially, these few, extremely central, hubs do not display particularly low expression correlation, undermining the idea of a link between this quantity and hub function. The date/party distinction was originally motivated by an approximately bimodal distribution of hub co-expression; we show that this feature is not always robust to methodological changes. Additionally, topological properties of hubs do not in general correlate with co-expression. However, we find significant correlations between interaction centrality and the functional similarity of the interacting proteins. We suggest that thinking in terms of a date/party dichotomy for hubs in protein interaction networks is not meaningful, and it might be more useful to conceive of roles for protein-protein interactions rather than for individual proteins.

  5. Ship Infrared Detection/Vulnerability

    NARCIS (Netherlands)

    Jong, A.N. de

    1993-01-01

    The IR contrast of ships at sea is of importance for those who want to detect or identify the ship and for those who worry about this. This IR contrast is determined by a large number of parameters. Of course temperatures of the ship's structure and those of the ambient sea and air are important, bu

  6. Location of an intermediate hub for port activities

    Science.gov (United States)

    Burciu, Ş.; Ştefănică, C.; Roşca, E.; Dragu, V.; Ruscă, F.

    2015-11-01

    An intermediate hub might increase the accessibility level of ports but also hinterland and so it can be considered more than a facility with a transhipment role. These hubs might lead to the development of other transport services and enhance their role in gathering and covering economic centres within hinterlands and also getting the part of logistic facility for the ports, with effects on port utilization and its connectivity to global economy. A new location for a hub terminal leads to reduced transport distances within hinterland, with decreased transport costs and external effects, so with gains in people's life quality. Because the production and distribution systems are relatively fixed on short and medium term and the location decisions are strategic and on long term, the logistic chains activities location models have to consider the uncertainties regarding the possible future situations. In most models, production costs are considered equal, the location problem reducing itself to a problem that aims to minimize the total transport costs, meaning the transport problem. The main objective of the paper is to locate a hub terminal that links the producers of cereals that are going to be exported by naval transportation with the Romanian fluvial-maritime ports (Galaţi, Brăila). GIS environment can be used to integrate and analyse a great amount of data and has the ability of using functions as location - allocation models necessary both to private and public sector, being able to determine the optimal location for services like factories, warehouses, logistic platforms and other public services.

  7. An environmental transfer hub for multimodal atom probe tomography

    Energy Technology Data Exchange (ETDEWEB)

    Perea, Daniel E.; Gerstl, Stephan S. A.; Chin, Jackson; Hirschi, Blake; Evans, James. E.

    2017-05-02

    Environmental control during transfer between instruments is required for specimens sensitive to air or thermal exposure to prevent morphological or chemical changes. Atom Probe Tomography is an expanding technique but commercial instruments remain limited to loading under ambient conditions. Here we describe a multifunctional environmental transfer hub allowing controlled cryogenic, atmospheric and vacuum transfer between an Atom Probe and other instruments containing separate chambers to allow downstream time-resolved in-situ studies.

  8. The new forging process of a wheel hub drop forging

    Directory of Open Access Journals (Sweden)

    A. Gontarz

    2006-08-01

    Full Text Available Purpose: The main purpose of the research was working out a new flashless forming process of wheel hubforging in three-slide forging press (TSFP. It was assumed that the new process would be more effective thanthe forging processes applied in typical forging machines.Design/methodology/approach: The designing of the new process was based on the simulation by finiteelement method with the assumption of 3D state of strain. Calculations were made mainly for the analysis of thematerial flow kinematics and the process loads parameters. Experimental research were also made determiningthe dependency of clamping load in the function of forming load. On the basis of the analysis, the formingprocess of a wheel hub drop forging on the TSFP was worked out.Findings: The results of research confirmed the possibility of flashless forming process of wheel hub forgingin TSFP with axial cavities. The main parameters limiting the forming processes of wheel hub forgings are:permissible upsetting ratio and reciprocal relation of forming and clamping forces.Research limitations/implications: The further research within the range of determining force parameters fordifferent types of material and schemata of forming in TSFP were considered as purposeful. The works dealingwith analysis of forming processes of different types of products in order to classify drop forgings possible toform in this press will be examined.Practical implications: The comparison of the new forming process with the forging process on hammershowed majority of advantages which include: decrease of time and energy, decrease of drop forging weight andmachining, decrease of material consumption.Originality/value: The new process of wheel hub forging forming with axial cavities was worked out. Theparameters important during designing of forming processes in TSFP were provided. The relations betweenforces of forming tools were also determined.

  9. The home hemodialysis hub: physical infrastructure and integrated governance structure.

    Science.gov (United States)

    Marshall, Mark R; Young, Bessie A; Fox, Sally J; Cleland, Calli J; Walker, Robert J; Masakane, Ikuto; Herold, Aaron M

    2015-04-01

    An effective home hemodialysis program critically depends on adequate hub facilities and support functions and on transparent and accountable organizational processes. The likelihood of optimal service delivery and patient care will be enhanced by fit-for-purpose facilities and implementation of a well-considered governance structure. In this article, we describe the required accommodation and infrastructure for a home hemodialysis program and a generic organizational structure that will support both patient-facing clinical activities and business processes.

  10. Robust design of a polygonal shaft-hub coupling

    Directory of Open Access Journals (Sweden)

    R. Citarella

    2015-10-01

    Full Text Available In this work, the Taguchi method is applied for the optimal choice of design parameter values for a polygonal shaft-hub coupling. The objective is to maximize a performance function, minimizing, at the same time, its sensitivity to noises factors (robust design. The Design of Experiments (DoE is adopted to set up a plan of numerical experiments, whose different configurations are simulated using the Boundary Element Method (BEM

  11. Performance evaluation of interconnected logistics networks confronted to hub disruptions

    OpenAIRE

    2016-01-01

    International audience; This paper investigates performance of interconnected logistics networks confronted to disruptions at hub level. With traditional supply chain network design, companies define and optimize their own logistics networks, resulting in current logistics systems being a set of independent heterogeneous logistics networks. The concept of PI aims to integrate independent logistics networks into a global, open, interconnected system. Prior research has shown that the new organ...

  12. Looking east, looking west: Penang as a knowledge hub

    OpenAIRE

    Gerke, Solvay; Evers, Hans-Dieter

    2012-01-01

    Penang has always been a focal point, absorbing knowledge (and popular culture) from civilizations to the East and West. In modern Penang the pattern of cultural contacts has changed over time. Research institutes and universities in Penang cooperate with foreign partners to produce research papers and reports. Based on an analysis of joint research output, the changing international position of Penang as an emerging research hub will be analysed. The paper will show that international cooper...

  13. A Hub Matrix Theory and Applications to Wireless Communications

    Directory of Open Access Journals (Sweden)

    H. T. Kung

    2007-01-01

    Full Text Available This paper considers communications and network systems whose properties are characterized by the gaps of the leading eigenvalues of AHA for a matrix A. It is shown that a sufficient and necessary condition for a large eigen-gap is that A is a “hub” matrix in the sense that it has dominant columns. Some applications of this hub theory in multiple-input and multiple-output (MIMO wireless systems are presented.

  14. Idea Exchange Music Hub Hits the Right Note in Community

    Directory of Open Access Journals (Sweden)

    Greg Bester

    2014-06-01

    Full Text Available The Cambridge Libraries and Galleries has made many changes over the last two years, rebranding as Idea Exchange and adding 3D printers, creative spaces and many on-site events. This article focuses on one of the organization’s newest innovations, the addition of a Music Hub, and the challenges of creating a space where members can learn and collaborate musically without disturbing those around them.

  15. Research dedusting efficiency of the inertial hub with adjustable parameters

    Directory of Open Access Journals (Sweden)

    Sharapov Rashid

    2016-01-01

    Full Text Available Production of construction materials every year production increases, thus increasing emissions pollutants into the atmosphere subjected to cleaning. At the enterprises of building materials production equipment becoming outdated both morally and physically exhausted their useful life. Technological design standards in the operation of purification equipment has undergone a number of changes. There are a large number of works devoted to the theory of cyclone separation. They examined calculation method and to determine the minimum size of particles is separated completely from the air stream in a cyclone. In theory, the high efficiency cyclones are relatively small separation of particles from the air stream. The experiments show that certain fractions of full capture occurs from the cyclones and out relatively large particles. Designed dust device hubs. They capture dust particles with low specific density and smaller than 5–10 microns. Rational use of hubs is achieved in the aspiration systems high performance. They are placed in front of or between the filter and the cyclone filter. Hub much reduces the amount of dust-laden air directed onto a thin cleaning. This reduces energy consumption for manufacturing as a whole, as well as, due to a possible decrease in performance fine filters, reducing their initial cost, metal consumption, maintenance costs and reduce the area occupied by them.

  16. Matrix logistics indicators assessment of distributed transport hub

    Directory of Open Access Journals (Sweden)

    Igor Arefyev

    2014-06-01

    Full Text Available Background: The paper is devoted to the distributed transport hub substantiation and assessment. The paper  was an example of the technique and form an array of logistical factors as variables that determine this condition. Experience in organizing multimodal transport showed that the "bottleneck" of transport logistics are items of cargo handling ports, terminals, freight stations and warehouses. At the core of the solution of these problems is the problem of estimating the variables determine the Multi-purpose Hubs. The aim is to develop a method of forming the system of logistical multiplying factors determine the role of each of the types in the technologiacal process of distributed Multi-purpose Hubs. Methods: The assessment model for the formation of Distributed Transport Units  can be based on formal methods to predict the behavior of complex systems engineering complexes. Then one of the approaches to the solution of the problem may be the matrix method of technological factors. Results and conclusions: The proposed methodology of the selection and validation of logistic coefficients has the practical importance in the models development for assessing the condition and behavior of Distributed Transport.

  17. The coffee genome hub: a resource for coffee genomes.

    Science.gov (United States)

    Dereeper, Alexis; Bocs, Stéphanie; Rouard, Mathieu; Guignon, Valentin; Ravel, Sébastien; Tranchant-Dubreuil, Christine; Poncet, Valérie; Garsmeur, Olivier; Lashermes, Philippe; Droc, Gaëtan

    2015-01-01

    The whole genome sequence of Coffea canephora, the perennial diploid species known as Robusta, has been recently released. In the context of the C. canephora genome sequencing project and to support post-genomics efforts, we developed the Coffee Genome Hub (http://coffee-genome.org/), an integrative genome information system that allows centralized access to genomics and genetics data and analysis tools to facilitate translational and applied research in coffee. We provide the complete genome sequence of C. canephora along with gene structure, gene product information, metabolism, gene families, transcriptomics, syntenic blocks, genetic markers and genetic maps. The hub relies on generic software (e.g. GMOD tools) for easy querying, visualizing and downloading research data. It includes a Genome Browser enhanced by a Community Annotation System, enabling the improvement of automatic gene annotation through an annotation editor. In addition, the hub aims at developing interoperability among other existing South Green tools managing coffee data (phylogenomics resources, SNPs) and/or supporting data analyses with the Galaxy workflow manager. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  18. Spider orientation and hub position in orb webs

    Science.gov (United States)

    Zschokke, Samuel; Nakata, Kensuke

    2010-01-01

    Orb-web building spiders (Araneae: Araneoidea, Uloboridae) can be considered as territorial central place foragers. In territorial central place foragers, the optimal foraging arena is circular, with the forager sitting in its centre. In orb webs, the spider’s orientation (head up or head down) whilst waiting for prey on the hub of its web and the downwards-upwards asymmetry of its running speeds are the probable causes for the observed deviation of the hub from the web’s centre. Here, we present an analytical model and a more refined simulation model to analyse the relationships amongst the spider’s running speeds, its orientation whilst waiting for prey and the vertical asymmetry of orb webs. The results of our models suggest that (a) waiting for prey head down is generally favourable because it allows the spider to reach the prey in its web on average quicker than spiders waiting head up, (b) the downwards-upwards running speed asymmetry, together with the head-down orientation of most spiders, are likely causes for the observed vertical asymmetry of orb webs, (c) waiting head up can be advantageous for spiders whose downwards-upwards running speed asymmetry is small and who experience high prey tumbling rates and (d) spiders waiting head up should place their hub lower than similar spiders waiting head down.

  19. Mapping Multiplex Hubs in Human Functional Brain Networks

    Science.gov (United States)

    De Domenico, Manlio; Sasai, Shuntaro; Arenas, Alex

    2016-01-01

    Typical brain networks consist of many peripheral regions and a few highly central ones, i.e., hubs, playing key functional roles in cerebral inter-regional interactions. Studies have shown that networks, obtained from the analysis of specific frequency components of brain activity, present peculiar architectures with unique profiles of region centrality. However, the identification of hubs in networks built from different frequency bands simultaneously is still a challenging problem, remaining largely unexplored. Here we identify each frequency component with one layer of a multiplex network and face this challenge by exploiting the recent advances in the analysis of multiplex topologies. First, we show that each frequency band carries unique topological information, fundamental to accurately model brain functional networks. We then demonstrate that hubs in the multiplex network, in general different from those ones obtained after discarding or aggregating the measured signals as usual, provide a more accurate map of brain's most important functional regions, allowing to distinguish between healthy and schizophrenic populations better than conventional network approaches. PMID:27471443

  20. Analysis of adhesion characteristics of liner dental materials

    Directory of Open Access Journals (Sweden)

    Đorđević Maja

    2013-01-01

    Full Text Available Adhesive characteristics of materials used in dental practice are determined by indirect methods, by measuring mechanical properties of liner materials. In that procedure, the adhesion is defined by using measured mechanical properties of the bond material-test sample, which has several shortages. In the presented research the focus was based on the multi-component, composite, materials, which have, both organic and inorganic components in their structures. The direct measure of material-dentine bond was used in order to quantify the adhesion properties of investigated liner materials. Artificial saliva was the media for inducing the liner-dentine bond destruction. Destruction measurements were made by applying the quantification of visual information methodology. Obtained results were used to calculate the adhesion coefficient of the liner materials. The results were correlated with the mechanical test. There are no references on comparative testing of adhesion mechanical properties of dental material in the literature with presented methodology. The presented methodology proved to be useful for the functional quality ranking of dental materials.

  1. Light-year scale radio cores in four LINER galaxies

    NARCIS (Netherlands)

    Filho, ME; Barthel, PD; Ho, LC

    2002-01-01

    The LINER galaxies NGC2911, NGC3079, NGC3998, and NGC6500 were observed at 5 GHz with the European VLBI Network at a resolution of 5 milliarcsecond and found to possess at-spectrum, variable, high-brightness temperature (T-B > 10(8) K) radio cores. These radio characteristics reinforce the view that

  2. The radio properties of composite liner/H II galaxies

    NARCIS (Netherlands)

    Filho, ME; Barthel, PD; Ho, LC

    2002-01-01

    Arcsecond-resolution VLA observations newly obtained as well as published of 40 nearby galaxies are discussed, completing a study of the radio properties of a magnitude-limited sample of nearby galaxies of the composite LINER/H II type. Our results reveal an overall detection rate of at least 25% ac

  3. Labial and Vaginal Microbiology: Effects of Extended Panty Liner Use

    Directory of Open Access Journals (Sweden)

    M. A. Farage

    1997-01-01

    Full Text Available Objective: The goals of this study were 1 to better define the labial microflora and 2 to evaluate whether extended non-menstrual use of panty liners would increase genital carriage of undesirable bacteria and predispose to infection.

  4. Auto-magnetizing liners for magnetized inertial fusion

    Science.gov (United States)

    Slutz, S. A.; Jennings, C. A.; Awe, T. J.; Shipley, G. A.; Hutsel, B. T.; Lamppa, D. C.

    2017-01-01

    The MagLIF (Magnetized Liner Inertial Fusion) concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)] has demonstrated fusion-relevant plasma conditions [Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z accelerator using external field coils to magnetize the fuel before compression. We present a novel concept (AutoMag), which uses a composite liner with helical conduction paths separated by insulating material to provide fuel magnetization from the early part of the drive current, which by design rises slowly enough to avoid electrical breakdown of the insulators. Once the magnetization field is established, the drive current rises more quickly, which causes the insulators to break down allowing the drive current to follow an axial path and implode the liner in the conventional z-pinch manner. There are two important advantages to AutoMag over external field coils for the operation of MagLIF. Low inductance magnetically insulated power feeds can be used to increase the drive current, and AutoMag does not interfere with diagnostic access. Also, AutoMag enables a pathway to energy applications for MagLIF, since expensive field coils will not be damaged each shot. Finally, it should be possible to generate Field Reversed Configurations (FRC) by using both external field coils and AutoMag in opposite polarities. This would provide a means to studying FRC liner implosions on the 100 ns time scale.

  5. FORENSIC INVESTIGATION OF A GENERATION OLD CIPP LINER

    Science.gov (United States)

    There is limited information regarding the in-situ performance of rehabilitation methods used for prolonging the service life of buried municipal pipeline systems. With some CIPP liners nearly 30 years in service, municipalities are expressing a strong interest in the collection ...

  6. Conductivity and transit time estimates of a soil liner

    Science.gov (United States)

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.H.; Herzog, B.L.

    1990-01-01

    A field-scale soil linear was built to assess the feasibilty of constructing a liner to meet the saturated hydraulic conductivity requirement of the U.S. EPA (i.e., less than 1 ?? 10-7 cm/s), and to determine the breakthrough and transit times of water and tracers through the liner. The liner, 8 ?? 15 ?? 0.9 m, was constructed in 15-cm compacted lifts using a 20,037-kg pad-foot compactor and standard engineering practices. Estimated saturated hydraulic conductivities were 2.4 ?? 10-9 cm/s, based on data from large-ring infiltrometers; 4.0 ?? 10-8 cm/s from small-ring infiltrometers; and 5.0 ?? 10-8 cm/s from a water-balance analysis. These estimates were derived from 1 year of monitoring water infiltration into the linear. Breakthrough of tracers at the base of the liner was estimated to be between 2 and 13 years, depending on the method of calculation and the assumptions used in the calculation.

  7. Critical interfaces in geosynthetic multilayer liner system of a landfill

    Directory of Open Access Journals (Sweden)

    Qian Xuede

    2008-12-01

    Full Text Available This study is to identify the critical interface in a geosynthetic multilayer liner system by examining the effects of the interface shear strength of liner components, leachate level, leachate buildup cases, and peak and residual interface strengths. According to current landfill design procedures, conducting stability analysis along the same interface at both the back slope and base may result in a non-conservative result. The critical interfaces with the minimum factor of safety are generally found at different locations along the back slope and base. The critical interface for a multilayer liner system cannot simply be assumed during stability analysis. It can shift from one interface to another with changes in the leachate level and with different leachate buildup cases. The factor of safety for an interface with a high friction angle and low apparent cohesion generally drops much more quickly than it does under inverse conditions when the leachate level increases. The failure interface in a liner system under residual conditions is usually different from the failure interface under peak conditions.

  8. The improvements on reactor building liner plate erection work

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Myungsub; Choi, Sangmoo [Ulchin Nuclear Division, KHNP, Seoul (Korea, Republic of)

    2002-04-15

    The pressurized water reactor, with its primary cooling circuit and steam generators, is housed in a cylindrical building. This 'containment' building is 44m in diameter and 80m high, and has a hemispherical or dome roof. A 6mm steel plate lines the entire interior of this containment building. This steel lining covers the floors, walls, dome and is made gas tight. There are more than 160 penetrations in the containment building for: equipment and personnel access, piping and electrical services. There are also over 370 field welded embedments fixed to the steel liner plate. Reducing construction costs of commercial nuclear power plants is essential in order to expand the future use of nuclear energy. One of the major components of reducing construction costs is the continuous improvement in construction technology. This is also essential in order to increase the nuclear culture in Quality Assurance of nuclear power plants. These improvements can make up for shortages in skilled craft labor necessary during site construction. In this paper, a number of improvements for the containment building steel liner plate fabrication and erection work will be described; adoption of flux core arc welding process, welding improvement in thickened liner plates, prefabrication of reactor cavity wall liner plates in the yard and optimization of the number of field welded embedments. Eventually these improvements may provide cost reduction and may allow reduction in the critical path schedule.

  9. Diagnostic Techniques to Elucidate the Aerodynamic Performance of Acoustic Liners

    Science.gov (United States)

    June, Jason; Bertolucci, Brandon; Ukeiley, Lawrence; Cattafesta, Louis N., III; Sheplak, Mark

    2017-01-01

    In support of Topic A.2.8 of NASA NRA NNH10ZEA001N, the University of Florida (UF) has investigated the use of flow field optical diagnostic and micromachined sensor-based techniques for assessing the wall shear stress on an acoustic liner. Stereoscopic particle image velocimetry (sPIV) was used to study the velocity field over a liner in the Grazing Flow Impedance Duct (GFID). The results indicate that the use of a control volume based method to determine the wall shear stress is prone to significant error. The skin friction over the liner as measured using velocity curve fitting techniques was shown to be locally reduced behind an orifice, relative to the hard wall case in a streamwise plane centered on the orifice. The capacitive wall shear stress sensor exhibited a linear response for a range of shear stresses over a hard wall. PIV over the liner is consistent with lifting of the near wall turbulent structure as it passes over an orifice, followed by a region of low wall shear stress.

  10. Contoured-gap coaxial guns for imploding plasma liner experiments

    Science.gov (United States)

    Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

    2014-10-01

    Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

  11. FORENSIC INVESTIGATION OF A GENERATION OLD CIPP LINER

    Science.gov (United States)

    There is limited information regarding the in-situ performance of rehabilitation methods used for prolonging the service life of buried municipal pipeline systems. With some CIPP liners nearly 30 years in service, municipalities are expressing a strong interest in the collection ...

  12. Towards Real Time Simulation of Ship-Ship Interaction

    DEFF Research Database (Denmark)

    Lindberg, Ole; Bingham, Harry B.; Engsig-Karup, Allan Peter

    2012-01-01

    We present recent and preliminary work directed towards the development of a simplified, physics-based model for improved simulation of ship-ship interaction that can be used for both analysis and real-time computing (i.e. with real-time constraints due to visualization). The goal is to implement...... the model into a large maritime simulator for training of naval officers, in particular tug boat helmsmen. Tug boat simulators are used for training of communication and situation awareness during manoeuvre involved with towing of large vessels. A main objective of the work is to improve and enable more...... accurate (realistic) and much faster ship-wave and ship-ship simulations than are currently possible. The coupling of simulation with visualization should improve the visual experience such that it can be perceived as more realistic in training. Today the state-of-art in real-time ship-ship interaction...

  13. Developing Shipping Emissions Assessments, Inventories and Scenarios (Invited)

    Science.gov (United States)

    Corbett, J. J.

    2010-12-01

    with economic and regulatory influences differently from other sources. The shifting stock of vessels from new-builds serving primary markets in one region to aging vessel technologies serving secondary markets produces substantial differences in future activity projections. This is compounded by the emissions differences between vessels on liner schedules and ships with similar technologies operating on charter or spot-market bases. Different rates of change drive growth among vessel types differently, so regional pattern shifts will occur, and need to be forecast or depicted in scenarios. Regulatory pathways are emerging with less clarity, but affect regional marine inputs. Scientists who measure emissions need to engage engineering principles of combustion, economics principles of supply and demand, and policy inputs to produce inventories that are more coherent, and more useful to the emerging purposes. Moreover, advanced studies (e.g., inverse modeling, source attribution, and control scenario validation) require design of “closure experiments”, where modeling of inventory measurements and modeled ambient impacts is corroborated and reconciled with field stack measurements and field observation campaigns. The most recent shipping inventories and scenarios are now providing details that recognize and address these issues.

  14. Stroke mimics under the drip-and-ship paradigm.

    Science.gov (United States)

    Mehta, Sonal; Vora, Nirav; Edgell, Randall C; Allam, Hesham; Alawi, Aws; Koehne, Jennifer; Kumar, Abhay; Feen, Eliahu; Cruz-Flores, Salvador; Alshekhlee, Amer

    2014-01-01

    Recent reports suggested better outcomes associated with the drip-and-ship paradigm for acute ischemic stroke (AIS) treated with thrombolysis. We hypothesized that a higher rate of stroke mimics (SM) among AIS treated in nonspecialized stroke centers that are transferred to comprehensive centers is responsible for such outcomes. Consecutive patients treated with thrombolysis according to the admission criteria were reviewed in a single comprehensive stroke center over 1 academic year (July 1, 2011 to June 30, 2012). Information on the basic demographic, hospital complications, psychiatric diagnoses, and discharge disposition was collected. We identified those patients who were treated at a facility and then transferred to the tertiary center (ie, drip-and-ship paradigm). In addition to comparative and adjusted analysis to identify predictors for SM, a stratified analysis by the drip-and-ship status was performed. One hundred twenty patients were treated with thrombolysis for AIS included in this analysis; 20 (16.7%) were discharged with the final diagnosis of SM; 14 of those had conversion syndrome and 6 patients had other syndromes (seizures, migraine, and hypoglycemia). Patients with SM were younger (55.6 ± 15.0 versus 69.4 ± 14.9, P = .0003) and more likely to harbor psychiatric diagnoses (45% versus 9%; P ≤ .0001). Eighteen of 20 SM patients (90%) had the drip-and-ship treatment paradigm compared with 65% of those with AIS (P = .02). None of the SM had hemorrhagic complications, and all were discharged to home. Predictors of SM on adjusted analysis included the drip-and-ship paradigm (odds ratio [OR] 12.8, 95% confidence interval [CI] 1.78, 92.1) and history of any psychiatric illness (OR 12.08; 95% CI 3.14, 46.4). Eighteen of 83 drip-and-ship patients (21.7%) were diagnosed with SM compared with 2 of 37 patients (5.4%) presented directly to the hub hospital (P = .02). The drip-and-ship paradigm and any psychiatric history predict the diagnosis of

  15. An analytical model for volatile organic compound transport through a composite liner consisting of a geomembrane, a GCL, and a soil liner.

    Science.gov (United States)

    Xie, Haijian; Jiang, Yuansheng; Zhang, Chunhua; Feng, Shijin

    2015-02-01

    An analytical model for volatile organic compounds (VOCs) transport through a composite liner consisting of a geomembrane (GM), a geosynthetic clay liner (GCL), and a soil liner (SL) was developed for the assessment of the performance of this triple liner system. Both advection through the defects of GM and diffusion in the intact GM were considered in the model, and dimensionless analytical solution was obtained. The soil concentration profiles obtained by the proposed analytical solution have a good agreement with those obtained by the finite-layer-based software POLLUTE v7. The effects of leachate head, length of the connected wrinkles, and the interface transmissivity of GM/GCL on the breakthrough curves of the liner system were then investigated. Results show that the 30-year base flux of the liner system for the case with leachate head = 10 m and length of the connected wrinkles = 1,000 m can be over 60 times greater than that of the pure diffusion case. The length of the connected wrinkles of the GM has greater influence on the base flux of the liner system than on the base concentration. The interface transmissivity has negligible effect on the solute breakthrough curves of the liner system for relatively low values of the length of the connected wrinkles (e.g., liners.

  16. Tendency of spherically imploding plasma liners formed by merging plasma jets to evolve toward spherical symmetry

    CERN Document Server

    Cassibry, J T; Hsu, S C; Abarzhi, S I; Witherspoon, F D

    2012-01-01

    Three dimensional hydrodynamic simulations have been performed using smoothed particle hydrodynamics (SPH) in order to study the effects of discrete jets on the processes of plasma liner formation, implosion on vacuum, and expansion. The pressure history of the inner portion of the liner was qualitatively and quantitatively similar from peak compression through the complete stagnation of the liner among simulation results from two one dimensional radiationhydrodynamic codes, 3D SPH with a uniform liner, and 3D SPH with 30 discrete plasma jets. Two dimensional slices of the pressure show that the discrete jet SPH case evolves towards a profile that is almost indistinguishable from the SPH case with a uniform liner, showing that non-uniformities due to discrete jets are smeared out by late stages of the implosion. Liner formation and implosion on vacuum was also shown to be robust to Rayleigh-Taylor instability growth. Interparticle mixing for a liner imploding on vacuum was investigated. The mixing rate was ve...

  17. Virtual Hubs for facilitating access to Open Data

    Science.gov (United States)

    Mazzetti, Paolo; Latre, Miguel Á.; Ernst, Julia; Brumana, Raffaella; Brauman, Stefan; Nativi, Stefano

    2015-04-01

    In October 2014 the ENERGIC-OD (European NEtwork for Redistributing Geospatial Information to user Communities - Open Data) project, funded by the European Union under the Competitiveness and Innovation framework Programme (CIP), has started. In response to the EU call, the general objective of the project is to "facilitate the use of open (freely available) geographic data from different sources for the creation of innovative applications and services through the creation of Virtual Hubs". In ENERGIC-OD, Virtual Hubs are conceived as information systems supporting the full life cycle of Open Data: publishing, discovery and access. They facilitate the use of Open Data by lowering and possibly removing the main barriers which hampers geo-information (GI) usage by end-users and application developers. Data and data services heterogeneity is recognized as one of the major barriers to Open Data (re-)use. It imposes end-users and developers to spend a lot of effort in accessing different infrastructures and harmonizing datasets. Such heterogeneity cannot be completely removed through the adoption of standard specifications for service interfaces, metadata and data models, since different infrastructures adopt different standards to answer to specific challenges and to address specific use-cases. Thus, beyond a certain extent, heterogeneity is irreducible especially in interdisciplinary contexts. ENERGIC-OD Virtual Hubs address heterogeneity adopting a mediation and brokering approach: specific components (brokers) are dedicated to harmonize service interfaces, metadata and data models, enabling seamless discovery and access to heterogeneous infrastructures and datasets. As an innovation project, ENERGIC-OD will integrate several existing technologies to implement Virtual Hubs as single points of access to geospatial datasets provided by new or existing platforms and infrastructures, including INSPIRE-compliant systems and Copernicus services. ENERGIC OD will deploy a

  18. EMP coupling to ships

    Energy Technology Data Exchange (ETDEWEB)

    Deadrick, F.J.; Cabayan, H.S.; Kunz, K.F.; Bevensee, R.M.; Martin, L.C.; Egbert, R.W.

    1980-01-01

    Scale-model tests were conducted to establish the adequacy and limitations of model measurements as tools for predicting electromagnetic pulse (EMP) coupling voltages and currents to the critical antennas, cables, and metallic structures on ships. The scale-model predictions are compared with the results of the full-scale EMP simulation test of the Canadian ASW ship, HMCS Huron. (The EMP coupling predictions in this report were made without prior knowledge of the results of the data from the HMCS Huron tests.) This report establishes that the scale-model tests in conjunction with the data base from EMP coupling modules provides the necessary information for source model development and permits effective, low-cost study of particular system configurations. 184 figures, 9 tables.

  19. Hydrodynamics of Ship Propellers

    DEFF Research Database (Denmark)

    Breslin, John P.; Andersen, Poul

    This book deals with flows over propellers operating behind ships, and the hydrodynamic forces and moments which the propeller generates on the shaft and on the ship hull.The first part of the text is devoted to fundamentals of the flow about hydrofoil sections (with and without cavitation......) and about wings. It then treats propellers in uniform flow, first via advanced actuator disc modelling, and then using lifting-line theory. Pragmatic guidance is given for design and evaluation of performance, including the use of computer modelling.The second part covers the development of unsteady forces...... arising from operation in non-uniform hull wakes. First, by a number of simplifications, various aspects of the problem are dealt with separately until the full problem of a non-cavitating, wide-bladed propeller in a wake is treated by a new and completely developed theory. Next, the complicated problem...

  20. Mechanics of Ship Grounding

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    In these notes first a simplified mathematical model is presented for analysis of ship hull loading due to grounding on relatively hard and plane sand, clay or rock sea bottoms. In a second section a more rational calculation model is described for the sea bed soil reaction forces on the sea bottom....... Finally, overall hull failure is considered first applying a quasistatic analysis model and thereafter a full dynamic model....

  1. Global Shipping Game

    Science.gov (United States)

    2011-01-28

    CDR Ed Suraci, and Mr. Leif Bergey . Cell Support: Each cell had an assigned data collection support assistant. These personnel assisted the players...Mr. Leif Bergey (Control Cell). Ethnographers (Environmental Recorders): Employed a variety of quasi-anthropological, ethnographic techniques to...for this project was Mr. Leif Bergey . Global Shipping Game Report 20 7 / 14 7 / 5 19 / 8 3 / 10 III. ANALYSIS

  2. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.

  3. Transformable Heavy Lift Ship

    Science.gov (United States)

    2007-08-01

    the 500 group include climate control, freshwater/seawater systems, mechanical handling, and special purpose systems. Due to the large troop...compliment carried on the JHSS, large amounts of climate control and ventilation were required. The transformable heavy lift ship has only a single... Treeline Connector Innovation Cell Naval Research Enterprise Intern Program Final Report, NSWCCD-20-TR-2005/05 August 2005 "Saturn." Nijhuis

  4. Contextual Hub Analysis Tool (CHAT: A Cytoscape app for identifying contextually relevant hubs in biological networks [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Tanja Muetze

    2016-08-01

    Full Text Available Highly connected nodes (hubs in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT, which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest.   Availability: CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store (http://apps.cytoscape.org/apps/chat.

  5. Consideration of liners and covers in performance assessments

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, Mark A. [Savannah River National Laboratory, Aiken, SC (United States); Seitz, Robert R. [Savannah River National Laboratory, Aiken, SC (United States); Suttora, Linda C. [USDOE Enviromental Management, Washington, DC (United States)

    2014-09-18

    On-site disposal cells are in use and being considered at several United States Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the U.S. Environmental Protection Agency under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management due to the radioactive waste. The USDOE-Environmental Management Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these CERCLA disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to CERCLA risk assessments and DOE Order 435.1 performance assessments in support of a Record of Decision and Disposal Authorization Statement, respectively. One of the issues considered by the working group, which is addressed in this report, was how to appropriately consider the performance of covers and liners/leachate collections systems in the context of a DOE Order 435.1 performance assessment (PA). This same information may be appropriate for consideration within CERCLA risk assessments for these facilities. These OSDCs are generally developed to meet hazardous waste (HW) disposal design standards under the Resource Conservation and Recovery Act (RCRA) as well as the DOE Order 435.1 performance based standards for disposal of radioactive waste. To meet the standards for HW, the facilities typically include engineered covers and liner/leachate collection systems. Thus, when considering such facilities in the context of a DOE Order 435.1 PA, there is a need to address the evolution of performance of covers and liner/leachate collection systems in the context of meeting a performance standard considering time

  6. A Model of Ship Auxiliary System for Reliable Ship Propulsion

    OpenAIRE

    Dragan Martinović; Mato Tudor; Dean Bernečić

    2012-01-01

    The main purpose of a vessel is to transport goods and passengers at minimum cost. Out of the analysis of relevant global databases on ship machinery failures, it is obvious that the most frequent failures occur precisely on the generator-running diesel engines. Any failure in the electrical system can leave the ship without propulsion, even if the main engine is working properly. In that case, the consequences could be devastating: higher running expenses, damage to the ship, oil spill or su...

  7. An Endosymbiotic Evolutionary Algorithm for the Hub Location-Routing Problem

    Directory of Open Access Journals (Sweden)

    Ji Ung Sun

    2015-01-01

    Full Text Available We consider a capacitated hub location-routing problem (HLRP which combines the hub location problem and multihub vehicle routing decisions. The HLRP not only determines the locations of the capacitated p-hubs within a set of potential hubs but also deals with the routes of the vehicles to meet the demands of customers. This problem is formulated as a 0-1 mixed integer programming model with the objective of the minimum total cost including routing cost, fixed hub cost, and fixed vehicle cost. As the HLRP has impractically demanding for the large sized problems, we develop a solution method based on the endosymbiotic evolutionary algorithm (EEA which solves hub location and vehicle routing problem simultaneously. The performance of the proposed algorithm is examined through a comparative study. The experimental results show that the proposed EEA can be a viable solution method for the supply chain network planning.

  8. The catheter hub disinfection cap as esophageal foreign body.

    Science.gov (United States)

    Tawfik, Kareem O; Myer, Charles M; Shikary, Tasneem; Goldschneider, Kenneth R

    2015-12-01

    Disinfection caps are increasingly being used to prevent catheter-associated bloodstream infections. These devices, designed for continuous passive disinfection of catheter hubs, are typically small and often brightly colored. As such, they have the potential to become pediatric airway and esophageal foreign bodies. We report two patients who developed esophageal foreign body following ingestion of disinfection caps. Given the increasing use of these devices, it is imperative that health care providers be aware of this potential iatrogenic problem. We propose that the use of disinfection caps may not be appropriate in pediatric patients with risk factors for foreign body ingestion.

  9. Wake center position tracking using downstream wind turbine hub loads

    Science.gov (United States)

    Cacciola, S.; Bertelè, M.; Schreiber, J.; Bottasso, C. L.

    2016-09-01

    Having an improved awareness of the flow within a wind farm is useful for power harvesting maximization, load minimization and design of wind farm layout. Local flow information at each wind turbine location can be obtained by using the response of the wind turbines, which are consequently used as distributed sensors. This paper proposes the use of hub loads to track the position of wakes within a wind farm. Simulation experiments conducted within a high-fidelity aeroservoelastic environment demonstrate the performance of the new method.

  10. Collective versus hub activation of epidemic phases on networks

    CERN Document Server

    Ferreira, Silvio C; Pastor-Satorras, Romualdo

    2015-01-01

    We consider a general criterion to discern the nature of the threshold in epidemic models on scale-free (SF) networks. Comparing the epidemic lifespan of the nodes with largest degrees with the infection time between them, we propose a general dual scenario, in which the epidemic transition is either ruled by a hub activation process, leading to a null threshold in the thermodynamic limit, or given by a collective activation process, corresponding to a standard phase transition with a finite threshold. We validate the proposed criterion applying it different to epidemic models, with waning immunity or heterogeneous infection rates.

  11. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    The technical feasibility of roll motion control devices has been amply demonstrated for over 100 years. Performance, however, can still fall short of expectations because of deciencies in control system designs, which have proven to be far from trivial due to fundamental performance limitations....... This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  12. Operational Options for Green Ships

    Institute of Scientific and Technical Information of China (English)

    Salma Sherbaz; Wenyang Duan

    2012-01-01

    Environmental issues and rising fuel prices necessitate better energy-efficiency in all sectors.The shipping industry is one of the major stakeholders,responsible for 3% of global CO2 emissions,14%-15% of global NOx emissions,and 16% of global SOx emissions.In addition,continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness.The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions.Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness.This paper provided a comprehensive review of basic concepts,principles,and potential of operational options for green ships.The key challenges pertaining to ship crew i.e.academic qualifications prior to induction,in-service training and motivation were discussed.The author also deliberated on remedies to these challenges.

  13. Operational options for green ships

    Science.gov (United States)

    Sherbaz, Salma; Duan, Wenyang

    2012-09-01

    Environmental issues and rising fuel prices necessitate better energy-efficiency in all sectors. The shipping industry is one of the major stakeholders, responsible for 3% of global CO2 emissions, 14%-15% of global NO X emissions, and 16% of global SO X emissions. In addition, continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness. The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions. Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness. This paper provided a comprehensive review of basic concepts, principles, and potential of operational options for green ships. The key challenges pertaining to ship crew i.e. academic qualifications prior to induction, in-service training and motivation were discussed. The author also deliberated on remedies to these challenges.

  14. A New Propulsion System for Ships.

    Science.gov (United States)

    1980-01-31

    complex relationships involving ship propulsion , ship control and a host of independent problems related to hydrodynamics, structural mechanics, efficiency...namely ship configuration and ship con- trol in addition to ship propulsion . The transmission pump can 1be used for boundary layer control on the...possibly overcome the limitation and performance shortcomings of existing ship propulsion systems. Light weight propulsion systems for naval ship

  15. Skin friction on a flat perforated acoustic liner

    Science.gov (United States)

    Boldman, D. R.; Brinich, P. F.

    1976-01-01

    The report concerns the measurement of friction coefficients of a typical perforated acoustic liner installed in the side of a wind tunnel. The results are compared with measured friction coefficients of a smooth hard wall for the same mean flow velocities in a wind tunnel. At a velocity of 61 m/sec, an increase in the local skin coefficient of only a few percent was observed, but at the highest velocity of 213 m/sec an increase of about 20% was obtained. This velocity is a realistic velocity for turbo-machinery components utilizing such liners, so a loss in performance is to be expected. Some tests were also performed to see if changes in the mean boundary layer induced by imposed noise would result in friction increase, but only at low velocity levels was such an increase in friction noted.

  16. Extended liner performance for hydrodynamics and material properties experiments

    CERN Document Server

    Reinovsky, R E

    2001-01-01

    Summary form only given, as follows. Over the last few years a new application for high performance pulsed power, the production of high energy density environments for the study of material properties under extreme conditions and hydrodynamics in complex geometries has joined the traditional family of radiation source applications. The newly commissioned Atlas pulsed power system at Los Alamos has replaced its predecessor, Pegasus, and joined the Shiva Star system at AFRL, Albuquerque and a variety of flux compression systems, principally at the All Russian Scientific Research Institute of Experimental Physics (VNIIEF) as ultra high current drivers for the high precision, magnetically imploded, near-solid density liner that is used to create the needed environments. Three families of experiments: the production of ultra strong shocks (>10 Mbar), the production of strongly coupled plasmas by liner compression of an initially dense plasma of a few eV temperature, and the compression of a magnetized plasma for ...

  17. Diagnosing magnetized liner inertial fusion experiments on Z

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, S. B., E-mail: sbhanse@sandia.gov; Gomez, M. R.; Sefkow, A. B.; Slutz, S. A.; Sinars, D. B.; Hahn, K. D.; Harding, E. C.; Knapp, P. F.; Schmit, P. F.; Awe, T. J.; McBride, R. D.; Jennings, C. A.; Geissel, M.; Harvey-Thompson, A. J.; Peterson, K. J.; Rovang, D. C.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Hess, M. H. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); and others

    2015-05-15

    Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (∼10{sup 12} DD neutrons) from multi-keV deuterium plasmas inertially confined by slow (∼10 cm/μs), stable, cylindrical implosions. Effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10{sup 10}. Analysis of extensive power, imaging, and spectroscopic x-ray measurements provides a detailed picture of ∼3 keV temperatures, 0.3 g/cm{sup 3} densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  18. Investigation of a Bio-Inspired Liner Concept

    Science.gov (United States)

    Koch, L. Danielle

    2017-01-01

    Four samples of natural reeds, Phragmites australis, were tested in the NASA Langley and Glenn Normal Incidence Impedance Tubes in order to experimentally determine the acoustic absorption coefficients as a function of frequency from 400 to 3000 Hz. Six samples that mimicked the geometry of the assemblies of natural reeds were also designed and additively manufactured from ASA thermoplastic and tested. Results indicate that structures can be manufactured of synthetic materials that mimic the geometry and the low frequency acoustic absorption of natural reeds. This accomplishment demonstrates that a new class of structures can now be considered for a wide range of industrial products that need thin, lightweight, broadband acoustic absorption effective at frequencies below 1000 Hz. Aircraft engine acoustic liners and aircraft cabin acoustic liners, in particular, are two aviation applications that might benefit from further development of this concept.

  19. Magneto-Rayleigh-Taylor growth and feedthrough in cylindrical liners

    Science.gov (United States)

    Weis, Matthew; Lau, Y. Y.; Gilgenbach, Ronald; Peterson, Kyle; Hess, Mark

    2013-10-01

    Cylindrical liner implosions in the MagLIF concept are susceptible to the magneto-Rayleigh-Taylor instability (MRT). The linearized ideal MHD equations are solved, including the presence of an axial magnetic field and the effects of sausage and kink modes. The eigenmode solution, using appropriate equilibrium profiles, allows an assessment of the local MRT growth rate and of the instantaneous feedthrough factor during the entire implosion process. Of particular interest will be the high convergence/stagnation phase, which is difficult to image experimentally. Strong axial magnetic fields can mitigate feedthrough and MRT growth, which may be useful at the fuel/liner interface during this phase of the MagLIF implosion. For the MRT growth rate and feedthrough factors, the LLNL code, HYDRA, is used to benchmark with the analytic theory, and with experiments on the Z-machine. This work was supported by DoE and NSF.

  20. Diagnosing Magnetized Liner Inertial Fusion experiments on Z

    Science.gov (United States)

    Hansen, Stephanie

    2014-10-01

    Recent Magnetized Liner Inertial Fusion (MagLIF) experiments performed at Sandia's Z facility have demonstrated DD fusion neutron yields above 1012 and effective confinement of charged fusion products by the flux-compressed magnetic field signaled by >1010 secondary DT neutrons. The neutron diagnostics are complemented by an extensive suite of visible and x-ray diagnostics providing power, imaging, and spectroscopic data. This talk will present analyses of emission and absorption features from the imploding and stagnating plasma that provide a consistent picture of the magnetic drive and the temperatures, densities, mix, and gradients in the fuel and liner at stagnation. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  1. Innovative Liner Concepts: Experiments and Impedance Modeling of Liners Including the Effect of Bias Flow

    Science.gov (United States)

    Kelly, Jeff; Betts, Juan Fernando; Fuller, Chris

    2000-01-01

    The study of normal impedance of perforated plate acoustic liners including the effect of bias flow was studied. Two impedance models were developed by modeling the internal flows of perforate orifices as infinite tubes with the inclusion of end corrections to handle finite length effects. These models assumed incompressible and compressible flows, respectively, between the far field and the perforate orifice. The incompressible model was used to predict impedance results for perforated plates with percent open areas ranging from 5% to 15%. The predicted resistance results showed better agreement with experiments for the higher percent open area samples. The agreement also tended to deteriorate as bias flow was increased. For perforated plates with percent open areas ranging from 1% to 5%, the compressible model was used to predict impedance results. The model predictions were closer to the experimental resistance results for the 2% to 3% open area samples. The predictions tended to deteriorate as bias flow was increased. The reactance results were well predicted by the models for the higher percent open area, but deteriorated as the percent open area was lowered (5%) and bias flow was increased. A fit was done on the incompressible model to the experimental database. The fit was performed using an optimization routine that found the optimal set of multiplication coefficients to the non-dimensional groups that minimized the least squares slope error between predictions and experiments. The result of the fit indicated that terms not associated with bias flow required a greater degree of correction than the terms associated with the bias flow. This model improved agreement with experiments by nearly 15% for the low percent open area (5%) samples when compared to the unfitted model. The fitted model and the unfitted model performed equally well for the higher percent open area (10% and 15%).

  2. Competitiveness of Slovenian Cargo Shipping

    Directory of Open Access Journals (Sweden)

    Milojka Počuča

    2012-10-01

    Full Text Available The paper presents Slovenian cargo shipping, its system oforganisation, ownership, age and value stntcture. It shows theimportance of shipping in the Slovenian overseas trade and itsimpact on the state's balance of payments. The analysis of thecompetitiveness of shipping was made from the viewpoint ofoperation costs and in comparison with the competitiveness ofEU shippers. The paper concludes with a proposal of possiblesystemic solutions which improve the competitiveness of Slovenianshipping.

  3. Future of Magnetohydrodynamic Ship Propulsion,

    Science.gov (United States)

    1983-08-16

    83 FOREIGN TECHNOLOGY DIVISION FUTURE OF MAGNETOHYDRODYNAMIC SHIP PROPULSION by A.P. Baranov DTIQ ~E tJ Approved for public release; 0.. distribution...MAGNETOHYDRODYNAMIC SHIP PROPULSION By: A.P. Baranov -,English pages: 10 Source: Sudostroyeniye, Nr. 12, December 1966, pp. 3-6 . Country of origin: USSR X...equations, etc. merged into this translation were extracted from the best quality copy available. FUTURE OF MAGNETOHYDRODYNAMIC SHIP PROPULSION A. P

  4. X-ray variability in AGN: LINER vs. Seyfert 2

    Science.gov (United States)

    Hernandez-Garcia, Lorena; Masegosa, Josefa; Gonzalez-Martin, Omaira; Marquez, Isabel

    2015-09-01

    Although variability is a general property characterizing active galactic nuclei (AGN), it is not well stablished if the changes occur in the same way in every nuclei . The main purpose of this work is to study the X-ray variability pattern(s) in low luminosity AGN in a large sample, including 18 low ionization nuclear emission line regions (LINERs) and 26 type 2 Seyferts (Sy2), using the public archives in Chandra and/or XMM-Newton. Spectra of the same source gathered at different epochs were simultaneously fitted to study long term variations, whereas the variability patterns were studied allowing different parameters to vary during the spectral fit. Whenever possible, short term variations from the analysis of the light curves and long term UV flux variability were studied. Short term variations are not found at X-rays, but variations in timescales of months/years is very common in both families. The main driver of the long term X-ray variations seems to be related to changes in the nuclear power in both LINERs and Sy2, but other variability patterns cannot be discarded in a few cases, because changes of the column density or at soft energies are also found. The X-ray variations occur in the same way in LINERs and type 2 Seyferts, i.e., related to the nuclear continuum, but they might have different accretion mechanisms. As absorption variations and changing-look sources are not observed in LINERs, but UV nuclear variations are common, we speculate that the BLR and the torus might disappear in these sources.

  5. NEW APPROACHES: A hot air balloon from dustbin liners

    Science.gov (United States)

    Weaver, Nicholas

    1998-07-01

    This article describes how a simple hot air balloon, inflated by a hair dryer, can be made out of household bin liners and Sellotape. It can be used at sixth-form level as an application of the ideal gas equation, = constant, and is rather more exciting than heated pistons. It gives a taste of a simple engineering design process, although the students do have to be reasonably adept at geometry and algebra.

  6. External Acoustic Liners for Multi-Functional Aircraft Noise Reduction

    Science.gov (United States)

    Jones, Michael G. (Inventor); Thomas, Russell H. (Inventor); Nark, Douglas M. (Inventor); Howerton, Brian M. (Inventor); Czech, Michael J. (Inventor)

    2017-01-01

    Acoustic liners for aircraft noise reduction include one or more chambers that are configured to provide a pressure-release surface such that the engine noise generation process is inhibited and/or absorb sound by converting the sound into heat energy. The size and shape of the chambers can be selected to inhibit the noise generation process and/or absorb sound at selected frequencies.

  7. Reliability-based condition assessment of steel containment and liners

    Energy Technology Data Exchange (ETDEWEB)

    Ellingwood, B.; Bhattacharya, B.; Zheng, R. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

    1996-11-01

    Steel containments and liners in nuclear power plants may be exposed to aggressive environments that may cause their strength and stiffness to decrease during the plant service life. Among the factors recognized as having the potential to cause structural deterioration are uniform, pitting or crevice corrosion; fatigue, including crack initiation and propagation to fracture; elevated temperature; and irradiation. The evaluation of steel containments and liners for continued service must provide assurance that they are able to withstand future extreme loads during the service period with a level of reliability that is sufficient for public safety. Rational methodologies to provide such assurances can be developed using modern structural reliability analysis principles that take uncertainties in loading, strength, and degradation resulting from environmental factors into account. The research described in this report is in support of the Steel Containments and Liners Program being conducted for the US Nuclear Regulatory Commission by the Oak Ridge National Laboratory. The research demonstrates the feasibility of using reliability analysis as a tool for performing condition assessments and service life predictions of steel containments and liners. Mathematical models that describe time-dependent changes in steel due to aggressive environmental factors are identified, and statistical data supporting the use of these models in time-dependent reliability analysis are summarized. The analysis of steel containment fragility is described, and simple illustrations of the impact on reliability of structural degradation are provided. The role of nondestructive evaluation in time-dependent reliability analysis, both in terms of defect detection and sizing, is examined. A Markov model provides a tool for accounting for time-dependent changes in damage condition of a structural component or system. 151 refs.

  8. Friction and wear behaviour of self lubricating bearing liners

    Science.gov (United States)

    Gay, Russell

    The thesis describes a numerical model for evaluating the variation of friction and wear of a self lubricating bearing liner over its useful wear life. Self-lubricating bearings have been in widespread use since the mid-1950s, particularly in the aerospace industry where they have the advantage of being low maintenance components. They are commonly used in relatively low speed, reciprocating applications such as control surface actuators, and usually consist of a spherical bearing with the inner and outer elements separated by a composite textile resin-bonded liner. A finite element model has been developed to predict the local stiffness of a particular liner at different states of wear. Results obtained using the model were used to predict the overall friction coefficient as it evolves due to wear, which is a novel approach. Experimental testing was performed on a bespoke flat-on-flat wear test rig with a reciprocating motion to validate the results of the friction model.. These tests were carried out on a commercially-available bearing liner, predominantly at a high contact pressure and an average sliding speed of 0.2 ms-1. Good agreement between predicted and experimentally measured wear was obtained when appropriate coefficients of friction were used in the friction model, and when the reciprocating sliding distance was above a critical value. A numerical wear model was also developed to predict the trend of backlash development in real bearing geometries using a novel approach. Results from the wear model were validated against full-scale bearing tests carried out elsewhere by the sponsoring company. Good agreement was obtained between the model predictions and the experimental results for the first 80% of the bearing wear life, and explanations for the discrepancy during the last 20% of the wear life have been proposed..

  9. The Radio Properties of Composite LINER/HII Galaxies

    CERN Document Server

    Filho, M E; Ho, L C; Filho, Mercedes E.; Barthel, Peter D.; Ho, Luis C.

    2002-01-01

    Arcsec-resolution VLA observations -- newly obtained as well as published -- of 40 nearby galaxies are discussed, completing a study of the radio properties of a magnitude-limited sample of nearby galaxies of the composite LINER/HII type. Our results reveal an overall detection rate of at least 25% AGN candidates among these composite sources. The general properties of these AGN candidates, as compared to non-AGN composite sources and HII galaxies, are discussed.

  10. The hubs of the human connectome are generally implicated in the anatomy of brain disorders.

    Science.gov (United States)

    Crossley, Nicolas A; Mechelli, Andrea; Scott, Jessica; Carletti, Francesco; Fox, Peter T; McGuire, Philip; Bullmore, Edward T

    2014-08-01

    Brain networks or 'connectomes' include a minority of highly connected hub nodes that are functionally valuable, because their topological centrality supports integrative processing and adaptive behaviours. Recent studies also suggest that hubs have higher metabolic demands and longer-distance connections than other brain regions, and therefore could be considered biologically costly. Assuming that hubs thus normally combine both high topological value and high biological cost, we predicted that pathological brain lesions would be concentrated in hub regions. To test this general hypothesis, we first identified the hubs of brain anatomical networks estimated from diffusion tensor imaging data on healthy volunteers (n = 56), and showed that computational attacks targeted on hubs disproportionally degraded the efficiency of brain networks compared to random attacks. We then prepared grey matter lesion maps, based on meta-analyses of published magnetic resonance imaging data on more than 20 000 subjects and 26 different brain disorders. Magnetic resonance imaging lesions that were common across all brain disorders were more likely to be located in hubs of the normal brain connectome (P brain disorders had lesions that were significantly more likely to be located in hubs (P human brain networks are more likely to be anatomically abnormal than non-hubs in many (if not all) brain disorders. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain.

  11. Design of targeted libraries against the human Chk1 kinase using PGVL Hub.

    Science.gov (United States)

    Peng, Zhengwei; Hu, Qiyue

    2011-01-01

    PGVL Hub is a Pfizer internal desktop tool for chemical library and singleton design. In this chapter, we give a short introduction to PGVL Hub, the core workflow it supports, and the rich design capabilities it provides. By re-creating two legacy targeted libraries against the human checkpoint kinase 1 (Chk1) as a showcase, we illustrate how PGVL Hub could be used to help library designers carry out the steps in library design and realize design objectives such as SAR expansion and improvement in both kinase selectivity and compound aqueous solubility. Finally we share several tips about library design and usage of PGVL Hub.

  12. ERDC Ship/Tow Simulator

    Data.gov (United States)

    Federal Laboratory Consortium — Performing Advanced Hydrodynamic ModelingEngineers and ship pilots can now overcome the challenges of evaluating navigation channel designs, modifications and safety...

  13. Ship Creek bioassessment investigations

    Energy Technology Data Exchange (ETDEWEB)

    Cushing, C.E.; Mueller, R.P.; Murphy, M.T.

    1995-06-01

    Pacific Northwest Laboratory (PNL) was asked by Elmendorf Air Force Base (EAFB) personnel to conduct a series of collections of macroinvertebrates and sediments from Ship Creek to (1) establish baseline data on these populations for reference in evaluating possible impacts from Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) activities at two operable units, (2) compare current population indices with those found by previous investigations in Ship Creek, and (3) determine baseline levels of concentrations of any contaminants in the sediments associated with the macroinvertebrates. A specific suite of indices established by the US Environmental Protection Agency (EPA) was requested for the macroinvertebrate analyses; these follow the Rapid Bioassessment Protocol developed by Plafkin et al. (1989) and will be described. Sediment sample analyses included a Microtox bioassay and chemical analysis for contaminants of concern. These analyses included, volatile organic compounds, total gasoline and diesel hydrocarbons (EPA method 8015, CA modified), total organic carbon, and an inductive-coupled plasma/mass spectrometry (ICP/MS) metals scan. Appendix A reports on the sediment analyses. The Work Plan is attached as Appendix B.

  14. Elastic Plastic Fracture Analysis of an Aluminum COPV Liner

    Science.gov (United States)

    Forth, Scott; Gregg, Bradley; Bailey, Nathaniel

    2012-01-01

    Onboard any space-launch vehicle, composite over-wrapped pressure vessels (COPVs) may be utilized by propulsion or environmental control systems. The failure of a COPV has the potential to be catastrophic, resulting in the loss of vehicle, crew or mission. The latest COPV designs have reduced the wall-thickness of the metallic liner to the point where the material strains plastically during operation. At this time, the only method to determine the damage tolerance lifetime (safe-life) of a plastically responding metallic liner is through full-scale COPV testing. Conducting tests costs substantially more and can be far more time consuming than performing an analysis. As a result of this cost, there is a need to establish a qualifying process through the use of a crack growth analysis tool. This paper will discuss fracture analyses of plastically responding metallic liners in COPVs. Uni-axial strain tests have been completed on laboratory specimens to collect elastic-plastic crack growth data. This data has been modeled with the crack growth analysis tool, NASGRO 6.20 to predict the response of laboratory specimens and subsequently the complexity of a COPV.

  15. Impact of consolidation pressure on contaminant migration in clay liner

    Directory of Open Access Journals (Sweden)

    Zhi-hong ZHANG

    2013-07-01

    Full Text Available Consolidation deformation occurs in clay liners under the self-weight of wastes at a simple garbage dump or dredged sediment dump, which leads to a decrease in the porosity. However, the migration of contaminants in clay liners is influenced by the porosity. Thus, the impact of consolidation deformation of clay liners on the migration of contaminants cannot be ignored. Based on Biot’s consolidation theory, the contaminant migration theory, and consideration of the three kinds of migration mechanisms of convection, diffusion, and adsorption, a one-dimensional migration model of contaminants in deforming porous media was established, and the finite difference method was adopted to obtain the numerical solutions for an established initial-boundary value problem. The impact of consolidation pressure on the migration law of a contaminant was studied. The results show that, regardless of adsorption modes, different consolidation pressures have similar impacts on the migration law of the contaminant. Namely, over a certain migration time, the greater the consolidation pressure is, the smaller the migration depth of the contaminant. The results also show that, while the migration time increases, the impact of a certain increment of consolidation pressure on the variation of contaminant concentration with the depth increases gradually and, while the migration depth increases, the impact of a certain increment of consolidation pressure on the variation of the contaminant concentration with time increases gradually.

  16. X-ray Measurements of Laser Irradiated Foam Filled Liners

    Science.gov (United States)

    Patankar, Siddharth; Mariscal, Derek; Goyon, Clement; Baker, Kevin; MacLaren, Stephan; Hammer, Jim; Baumann, Ted; Amendt, Peter; Menapace, Joseph; Berger, Bob; Afeyan, Bedros; Tabak, Max; Dixit, Sham; Kim, Sung Ho; Moody, John; Jones, Ogden

    2016-10-01

    Low-density foam liners are being investigated as sources of efficient x-rays. Understanding the laser-foam interaction is key to modeling and optimizing foam composition and density for x-ray production with reduced backscatter. We report on the experimental results of laser-irradiated foam liners filled with SiO2 and Ta2O5 foams at densities between 2 to 30mg/cc. The foam liners consist of polyimide tubes filled with low-density foams and sealed with a gold foil at one end. The open end of the tube is driven with 250J of 527nm laser light in a 2ns 2-step pulse using the Jupiter Laser Facility at LLNL. A full aperture backscatter system is used to diagnose the coupled energy and losses. A streaked x-ray camera and filtered x-ray pinhole cameras are used to measure laser penetration into the low-density foam for different mass densities. A HOPG crystal spectrometer is used to estimate a thermal electron temperature. Comparisons with beam propagation and x-ray emission simulations are presented. This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, with funding support from the Laboratory Directed Research and Development Program under project 15.

  17. 3D printed liner for treatment of periprosthetic joint infections.

    Science.gov (United States)

    Kim, Tae Won B; Lopez, Osvaldo J; Sharkey, Jillian P; Marden, Kyle R; Murshed, Muhammad Ridwan; Ranganathan, Shivakumar I

    2017-05-01

    In the United States, long standing deep infections of joint arthroplasty, such as total knee and total hip replacements, are treated with two-stage exchange. This requires the removal of the prior implant, placement of an antibiotic eluting spacer block made of polymethylmethacrylate (PMMA), followed by re-implantation of a new implant after treatment with intravenous antibiotics for six to eight weeks. Unfortunately, the use of PMMA as a spacer material has limitations in terms of mechanical and drug-eluting properties. PMMA is brittle and elutes most of the antibiotics within the first few days. Furthermore, the polymerization reaction for PMMA is highly exothermic, thereby limiting the use to heat-stable antibiotics. We hypothesize that the use of a 3D printed polymeric liner made of polylactic acid (PLA) would overcome the limitations of PMMA because it is a stronger and a less brittle material than PMMA. Furthermore, the liner can also act as a controlled drug delivery vehicle by using built in reservoirs and a network of micro-channels as well as by incorporating antibiotics directly into the polymer during manufacturing stage. Finally, the liner can be 3D printed according to the anatomy of the patient and thereby has the potential to transform the manner in which periprosthetic joint infections are currently treated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Experimental progress toward magnetized liner inertial fusion on Z

    Science.gov (United States)

    Sinars, Daniel; Herrmann, Mark; Cuneo, Michael; Lamppa, Derek; Lopez, Andrew; McBride, Ryan; Rovang, Dean; Hanson, David; Harding, Eric; Nakhleh, Charles; Slutz, Stephen; Vesey, Roger; Sefkow, Adam; Peterson, Kyle

    2011-10-01

    Yields exceeding 100 kJ may be possible on the 25 MA Z facility at Sandia using the implosion of cylindrical metal liners onto magnetized (>10 T) and preheated (100-500 eV) deuterium-tritium fuel [S.A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. The fusion fuel in such targets absorbs about 100 kJ, so a 100 kJ yield would be `scientific breakeven.' Suitable liner targets (Al and Be) have been fabricated and used in experiments on the magneto-Rayleigh-Taylor instability. Magnetic field coil prototypes for >10 T axial fields are being tested. Preheat experiments using the multi-kJ Z-Beamlet laser are planned. Cryogenic deuterium fuel systems have been developed. Integrated magnetized liner inertial fusion (MagLIF) tests using deuterium fuel are expected in 2013. Sandia is a multiprogram laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  19. A semi-analytic model of magnetized liner inertial fusion

    Science.gov (United States)

    McBride, Ryan D.; Slutz, Stephen A.

    2015-05-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  20. A semi-analytic model of magnetized liner inertial fusion

    Energy Technology Data Exchange (ETDEWEB)

    McBride, Ryan D.; Slutz, Stephen A. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2015-05-15

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  1. A Physics Exploratory Experiment on Plasma Liner Formation

    Science.gov (United States)

    Thio, Y. C. Francis; Knapp, Charles E.; Kirkpatrick, Ronald C.; Siemon, Richard E.; Turchi, Peter

    2002-01-01

    Momentum flux for imploding a target plasma in magnetized target fusion (MTF) may be delivered by an array of plasma guns launching plasma jets that would merge to form an imploding plasma shell (liner). In this paper, we examine what would be a worthwhile experiment to do in order to explore the dynamics of merging plasma jets to form a plasma liner as a first step in establishing an experimental database for plasma-jets driven magnetized target fusion (PJETS-MTF). Using past experience in fusion energy research as a model, we envisage a four-phase program to advance the art of PJETS-MTF to fusion breakeven Q is approximately 1). The experiment (PLX (Plasma Liner Physics Exploratory Experiment)) described in this paper serves as Phase I of this four-phase program. The logic underlying the selection of the experimental parameters is presented. The experiment consists of using twelve plasma guns arranged in a circle, launching plasma jets towards the center of a vacuum chamber. The velocity of the plasma jets chosen is 200 km/s, and each jet is to carry a mass of 0.2 mg - 0.4 mg. A candidate plasma accelerator for launching these jets consists of a coaxial plasma gun of the Marshall type.

  2. Increased tubing lifetime with PE-X liners

    Energy Technology Data Exchange (ETDEWEB)

    Haager, Markus [AGRU Kunststofftechnik GmbH, Bad Hall (Austria)

    2011-12-15

    Tubing failures are still one of the most common and expensive ones in sucker rod pump and progressive cavity pump installations. In many cases the actual cause of tubing failure is a synergistic effect of the rods wearing on the tubing wall (abrasion) coupled with an electrochemical attack (corrosion). To increase the lifetime of tubings as well as the average time betweenworkovers and thus reduce production costs the R and D project ''Lined Tubing'' was initiated by the Austrian oil and gas company OMV and the polymer producer Borealis. The conducted research facilitated a better understanding of the abrasion caused by the contact of couplings with the thermoplastic tubing liners. Altogether 19 different thermoplastic materials were evaluated. Combining all available results it was concluded that tubing liners made from cross-linked polyethylene (PE-X) provide the most efficient solution. Thus, this new technology was patented under WO 2009/080556 [1]. Up to today more than 250 oil wells operating with sucker rod pumps and progressive cavity pumps were equipped with tubing liners by OMV (Austria), PETROM (Romania) and RAG (Austria). Statistical evaluations clearly showed the benefits of significantly increased running times which result in reduced maintenance and production costs. (orig.)

  3. Method of minimizing liner expansion issues in horizontal thermal applications

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, R.; Cavender, T. [Halliburton, Houston, TX (United States)

    2009-07-01

    This study reviewed well casing and liner applications used in a variety of thermal recovery operations such as steam-assisted gravity drainage (SAGD), cyclic steam stimulation (CSS), steam flooding, multilateral injection, and steam enhanced oil recovery (EOR) in depleted cold heavy-oil production with sand (CHOPS) recovery methods. Completion casing and liners are typically deployed at relatively low downhole temperature conditions. Subsequent steam injection then causes downhole temperatures to increase, causing thermal expansion in downhole tubulars and other components. The thermal stresses can result in tubular buckling and parting. Providing room for expansion when downhole components are heated can reduce the risk of failures. This study discussed a temperature-activated travel joint designed to function as a static pup joint or casing collar. The device transmits full torque and tensile strength when temperatures remain below a predetermined value. When steam or other thermal fluids are introduced into the well, thermal expansion devices are activated in order to allow the thermal expansion of adjacent components without associated thermal expansion-related stresses. Tests conducted to validate the design showed that the technology can be used with slotted liner and sand screen applications as well as with concentric tubing configurations. 9 refs., 14 figs.

  4. PASSENGER SERVICE QUALITY PARAMETERS ASSESSMENT AT TRANSPORT INTERCHANGE HUBS

    Directory of Open Access Journals (Sweden)

    Kozlov Pavel Igorevich

    2017-05-01

    Full Text Available The article discusses a quality assessment method for transport decisions made in transport interchange hubs. Analysis of domestic regulatory documentation and international experience on this subject is performed. It is stated that the domestic regulatory documentation lacks such method of assessment. Special attention is paid to study of pedestrian flows in interchange complexes of intermodal transport interchange hubs. The aim of the study is development of the Level of Service comprehensive assessment criterion by analogy with the international practice. The authors propose to use the queueing theory with elements of the theory of graphs, techniques and regularities that underlie the Level of Service (service factor applied in planning and location of TIH in the USA as well as data from field surveys carried out by the pedestrian flows video detection method. During the field surveys it is planned to perform analysis of external and internal factors influencing the formation and composition of a pedestrian flow, to determine quantitative values of the main parameters of pedestrian flow (density, speed, intensity and regularities of their variation depending on the design features of pedestrian traffic environment. Determination of passenger service quality factors in TIH will help to develop an integral criterion based on the Level of Service, taking into account the specifics of TIH functioning in Russia as well as a methodology that allows a reasonable choice of combinations of structural elements and planning parameters of pedestrian traffic objects which will let to reduce construction costs and operating costs for location of interchange complexes.

  5. Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review

    Science.gov (United States)

    Moureau, Nancy L.

    2015-01-01

    Background. Needleless connectors (NC) are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33–45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5–60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48–86% reduction). Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection. PMID:26075093

  6. Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review

    Directory of Open Access Journals (Sweden)

    Nancy L. Moureau

    2015-01-01

    Full Text Available Background. Needleless connectors (NC are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33–45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5–60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48–86% reduction. Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection.

  7. Design and Development of an Integrated Workstation Automation Hub

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Andrew; Ghatikar, Girish; Sartor, Dale; Lanzisera, Steven

    2015-03-30

    Miscellaneous Electronic Loads (MELs) account for one third of all electricity consumption in U.S. commercial buildings, and are drivers for a significant energy use in India. Many of the MEL-specific plug-load devices are concentrated at workstations in offices. The use of intelligence, and integrated controls and communications at the workstation for an Office Automation Hub – offers the opportunity to improve both energy efficiency and occupant comfort, along with services for Smart Grid operations. Software and hardware solutions are available from a wide array of vendors for the different components, but an integrated system with interoperable communications is yet to be developed and deployed. In this study, we propose system- and component-level specifications for the Office Automation Hub, their functions, and a prioritized list for the design of a proof-of-concept system. Leveraging the strength of both the U.S. and India technology sectors, this specification serves as a guide for researchers and industry in both countries to support the development, testing, and evaluation of a prototype product. Further evaluation of such integrated technologies for performance and cost is necessary to identify the potential to reduce energy consumptions in MELs and to improve occupant comfort.

  8. Fusion Reactor and Break-Even Experiment Based on Stabilized Liner Compression of Plasma

    Science.gov (United States)

    Turchi, Peter; Frese, Sherry; Frese, Michael

    2016-10-01

    An optimum regime, known as magnetized-target or magneto-inertial fusion (MTF/MIF), requires magnetic fields at megagauss levels, which are attainable by use of dynamic conductors called liners. The stabilized liner compressor (SLC) provides the basis for controlled implosion and re-capture of the liner for reversible energy exchange between liner kinetic energy and the internal energy of a magnetized-plasma target. This exchange requires rotational stabilization of Rayleigh-Taylor modes on the inner surface of the liner and pneumatically driven free-pistons that eliminate such modes at the outer surface. We discuss the implications of the SLC approach for the power reactor, a breakeven experiment, and intermediate experiments to develop the plasma target. Features include the importance of pneumatic drive and the liner-blanket for economic feasibility of MTF/MIF. Supported by ARPA-E ALPHA Program.

  9. Comparative evaluation of 2% sodium fluoride iontophoresis and other cavity liners beneath silver amalgam restorations

    Directory of Open Access Journals (Sweden)

    Gupta M

    2010-06-01

    Full Text Available Background: This study was designed to compare 2% sodium fluoride (NaF iontophoresis with other cavity liners. Materials and Methods: This study was carried out in 30 patients in the age group 10-14 years with bilateral carious permanent first molars. The study evaluated the use of 2% NaF iontophoresis as a cavity liner and also compared its desensitizing effect with varnish and an adhesive bonded liner. Sensitivity gradings were done on a subjective verbal rating scale. Results: All the liner treatments decreased the sensitivity following liner application. However, decrease of sensitivity in the case of 2% NaF iontophoresis was more compared with that of varnish and adhesive bonded liner. The results were statistically significant. Conclusions: It was found that 2% NaF iontophoresis was more effective in reducing the postoperative sensitivity compared with that of varnish and scotchbond multipurpose.

  10. Fabrication of Machined and Shrink Fitted Impactor; Composite Liners for the Los Alamos HEDP Program

    Energy Technology Data Exchange (ETDEWEB)

    Randolph, B.

    1999-10-19

    Composite liners have been fabricated for the Los Alamos liner driven HEDP experiments using impactors formed by physical vapor deposition (PVD), electroplating, machining and shrink fitting. Chemical vapor deposition (CVD) has been proposed for some ATLAS liner applications. This paper describes the processes used to fabricate machined and shrink fitted impactors which have been used for copper impactors in 1100 aluminum liners and 6061 T-6 aluminum impactors in 1100 aluminum liners. The most successful processes have been largely empirically developed and rely upon a combination of shrink fitted and light press fitting. The processes used to date will be described along with some considerations for future composite liners requirements in the HEDP Program.

  11. Ship Systems Staging Diagrams for DDG-37 Class Ships.

    Science.gov (United States)

    1977-12-01

    Naval Air Systems Command ( NA VELEX - Naval Electronics Systems CommandNAVSEA - Naval Sea Systems Command NA VSEC - Naval Ships Engineering Center...Configuration Accounting System (SECAS) 93.2 . 3 Technical Systems Commands (NAVSEA, NA VELEX ) . 9 3. 2. 4 Type Commanders (TYCOMs~ 9I 3. 2. 5 Nava l Ships

  12. On the Global Ship Hull Bending Energy in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Y.

    2004-01-01

    During ship collisions part of the kinetic energy of the involved vessels prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can be stored in elastic...... absorbed by the struck ship normally is small and varies from 1 to 6 % of the energy released for crushing. The energy stored as elastic global hull girder vibrations depends on the ship mass, the local stiffness of the side structure, and of the position of contact. The results also show that for highly...... hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non trivial part of the energy released for structural deformation during the collision can be absorbed as elastic energy in global...

  13. On the global ship hull bending energy in ship collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Yujie

    2009-01-01

    be stored in elastic hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non-trivial part of the energy released for structural deformation during the collision can be absorbed as elastic...... energy absorbed by the struck ship normally is small and varies from 1 to 6% of the energy released for crushing. The energy stored as elastic global hull girder vibrations depends on the ship mass, the local stiffness of the side structure, and of the position of contact. The results also show......During ship collisions part of the kinetic energy of the involved vessels immediately prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can...

  14. On Impact Mechanics in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship-ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

  15. Liner surface improvements for low friction piston ring packs

    Science.gov (United States)

    Anderberg, C.; Dimkovski, Z.; Rosén, B.-G.

    2014-01-01

    The development of engine components in the automotive industry is governed by several constraints such as environmental legislation and customer expectations. About a half of the frictional losses in an internal combustion engine come from the interactions between the piston assembly and cylinder liner surface. The tribological considerations in the contact between the piston ring and cylinder liner have attracted much attention over the past few decades. Many non-conventional cylinder liner finishes have been, and are being, developed with the aim to reduce friction losses and oil consumption, but the effects of the surface finish on piston ring pack performance is not well understood. One way of reducing friction in the cylinder system is to reduce the tangential load from the piston ring pack, focusing on the oil control ring. However, the side-effect of this is a disappointingly increased oil consumption. In this study a number of different cylinder liner surface specifications were developed and implemented in test engines with the aim of maintaining the level for oil consumption when decreasing the tangential load for the piston ring pack. To improve our understanding of the result, the same surfaces were evaluated in elastic and elasto-plastic rough contact and hydrodynamic flow simulation models. It is shown that oil consumption is strongly related to surface texture on the cylinder liners and at lower speeds (900-1200 rpm), a ‘rougher surface’ with a high core (e.g. Sk) and valley roughness (e.g. Svk) results in higher oil consumption. At the medium speed range (1200-3600 rpm), oil consumption continues to dominate for the ‘rough’ surfaces but with a visible influence of a lower oil consumption for a decreased roughness within the ‘rough’ surface group. ‘Smooth’ surfaces with a ‘smooth’ core (Sk), irrespective of the valley component (Svk), show similar oil consumption. For engine speeds above 3600 rpms, an increase in plateau

  16. Effect of liner and porcelain application on zirconia surface structure and composition

    Institute of Scientific and Technical Information of China (English)

    Tariq F Alghazzawi; Gregg M Janowski

    2016-01-01

    The purpose of this study was to determine if there is an effect of liner and porcelain application (layering and pressing techniques) on the surface of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP), which were exposed to permutations of liner, layered porcelain, and pressed porcelain. Scanning electron microscope (SEM)/energy dispersive spectroscope (EDS) was used to identify changes in composition and microstructure after removing liner and porcelain with hydrofluoric acid. Simulated aging was also conducted to determine the effect of liner and porcelain on low-temperature degradation. The control group had a typical equiaxed grain structure, referred to as unaffected. When covered with liner or porcelain, some areas changed in structure and composition and were termed affected. The frequency of affected structure decreased when liner was covered with either layered porcelain or pressed porcelain. There were statistical differences (Po0.05) in the composition between affected and unaffected for zirconium (layered porcelain with liner:affected=60%(0.8%) (m/m), unaffected=69%(4%), layered porcelain without liner:affected=59%(3%), unaffected=65%(3%)) and oxygen (layered porcelain with liner:affected=35%(2%), unaffected=26%(4%), layered porcelain without liner:affected=35%(3%), unaffected=30%(2%)). However, there were statistical differences (Po0.05) in the composition for zirconium and oxygen of the aged layered porcelain without liner only. The liner should not be used before porcelain application, especially when using the layering technique for zirconia restorations. Furthermore, pressing should be considered the technique of choice over layering.

  17. Dynamical Process of Liner Implosion in the Electromagnetic Flux Compression for Ultra-high Magnetic Fields

    CERN Document Server

    Nakamura, Daisuke; Matsuda, Yasuhiro H; Takeyama, Shojiro

    2013-01-01

    The spatial distribution of magnetic fields that are generated by the electromagnetic flux compression technique is investigated, with emphasis on the dynamical processes of an imploding liner. By comparing with the results of computer simulations, we found that the non-uniform implosion of a liner is important in order to explain the magnetic field's distribution during the liner's implosion. In addition, our results suggest that the initial inwards compressing spool-like motion of the liner subsequently turns out to be outwards stretching barrel-like motion along the magnetic field axis.

  18. Development of reduced drag concepts for acoustic liners using experimental methods

    Science.gov (United States)

    Jasinski, Christopher

    2016-11-01

    Commercial aircraft have used acoustic liners to reduce engine noise for many years, although their drag production has been largely unstudied. The next generation of aircraft may benefit from additional surface area covered by acoustic liner, thus understanding their drag production mechanism is crucial for future designs. An accurate direct aerodynamic drag measurement technique has been developed using a force balance with linear air bearings. Using 3D-printed and conventional liners, low-drag designs are being developed. This paper will investigate the underlying fluid mechanics governing the drag production in acoustic liners and describe new attempts to reduce aerodynamic drag.

  19. Analysis of diffusion-adsorption equivalency of landfill liner systems for organic contaminants.

    Science.gov (United States)

    Xie, Haijian; Chen, Yunmin; Ke, Han; Tang, Xiaowu; Chen, Renpeng

    2009-01-01

    The equivalence between multilayered barriers regarding diffusion and adsorption was studied. The bottom boundary of the liner system is defined by assuming concentration continuous and flux continuous conditions of the contaminant between the bottom liner layer and the underlying soil. Five different liner systems were compared in terms of solute breakthrough time. The results of the analysis showed that breakthrough time of the hydrophobic organic compounds for a 2-meter-thick compacted clay liner (CCL) could be 3-4 orders of magnitude is greater than the breakthrough time for a geosynthetic clay liner (GCL) composite liner. The GM/GCL and GM/CCL composite liner systems provide a better diffusion barrier for the hydrophilic organic compounds than that for the hydrophobic compounds due to their different Henry's coefficient. The calculated breakthrough times of the organic contaminants for the Chinese standard liner systems were found to be generally greater than those for the GCL alternatives, for the specific conditions examined. If the distribution coefficient increases to 2.8 for the hydrophobic compounds or 1.0 for the hydrophilic compounds, the thickness of the attenuation layer needed to achieve the same breakthrough time as the standard liner systems can be reduced by a factor of about 1.9-2.4. As far as diffusive and adsorption contaminant transport are concerned, GM or GCL is less effective than CCL.

  20. Analysis of diffusion-adsorption equivalency of landfill liner systems for organic contaminants

    Institute of Scientific and Technical Information of China (English)

    XIE Haijian; CHEN Yunmin; KE Han; TANG Xiaowu; CHEN Renpeng

    2009-01-01

    The equivalence between multilayered barriers regarding diffusion and adsorption is analyzed by means of an analytical method. The bottom boundary of the liner system is defined by assuming concentration continuous and flux continuous conditions of the contaminant between the bottom liner layer and the underlying soil. Five different liner systems were compared in terms of solute breakthrough time. The results of the analysis show that breakthrough time of the hydrophobic organic compounds for a 2-meter-thick compacted clay liner (CCL) can be 3-4 orders of magnitude greater than the breakthrough time for a geosynthetic clay liner (GCL) composite liner. The GM/GCL and GM/CCL composite liner systems provide a better diffusion barrier for the hydrophilic organic compounds than that for the hydrophobic compounds due to their different Henry's coefficient. The calculated breakthrough times of the organic contaminants for the Chinese standard liner systems were found to be generally greater than those for the GCL alternatives, for the specific conditions examined. If the distribution coefficient increases to 2.8 for the hydrophobic compounds or 1.0 for the hydrophilic compounds, the thickness of the attenuation layer needed to achieve the same breakthrough time as the standard liner systems can be reduced by a factor of about 1.9-2.4. As far as diffusive and adsorption contaminant transport are concerned, GM or GCL is less effective than CCL.

  1. Development of reactive artificial liner using recycled materials. 2. Chemical transport properties.

    Science.gov (United States)

    Chin, Johnnie Y; Asavanich, Pitch; Moon, Kyong-Whan; Park, Jae K

    2013-07-01

    Volatile organic compounds (VOCs) have so far been found to permeate through geomembranes within days and potentially pollute the surrounding groundwater if no sufficient depth of underlain soil barrier existed In order to cope with the fast breakthrough of VOCs through high-density polyethylene (HDPE) geomembrane in the composite liner system, a composite material made of recycled materials was proposed and its mechanical properties were analyzed in a previous study. This artificial liner was composed of crumb rubber, organo-clay, silica fume and epoxy binder together with an environmentally-friendly solvent recycled from paper pulping, and dimethyl sulfoxide as a plasticizer. In this study, the new artificial liner and a typical HDPE geomembrane were tested to compare their abilities to mitigate the movement of VOCs, specifically partition coefficient, diffusion coefficient and mass fluxes. It was found that this new artificial liner had 2-3 orders of magnitude less VOC mass flux than the HDPE geomembrane. The new artificial liner is thought to have a great potential for containing VOCs, even with a thickness of 2.5 cm, and as a substitute for the clay liner. The cost of installing the artificial liner was estimated to be $13.78/m(2). This is lower than the current geomembrane-related price of $19.70-26.91/m(2). The new liner might give a new perspective in future liner design and alleviate the concerning issue of groundwater pollution caused by landfill leachate, which might contain highly mobile VOCs.

  2. Efficiency of pulse high-current generator energy transfer into plasma liner energy

    Science.gov (United States)

    Oreshkin, V. I.

    2013-08-01

    The efficiency of capacitor-bank energy transfer from a high-current pulse generator into kinetic energy of a plasma liner has been analyzed. The analysis was performed using a model including the circuit equations and equations of the cylindrical shell motion. High efficiency of the energy transfer into kinetic energy of the liner is shown to be achieved only by a low-inductance generator. We considered an "ideal" liner load in which the load current is close to zero in the final of the shell compression. This load provides a high (up to 80%) efficiency of energy transfer and higher stability when compressing the liner.

  3. Precautionay Seizure of Civil Ship

    Directory of Open Access Journals (Sweden)

    Ciprian Alexandrescu

    2011-05-01

    Full Text Available Noting that many pending cases in the maritime and river sections of the courts concern the seizureof commercial ships, we intend to study in detail this institution of maritime law. This approach is due to thefact that the few Romanian law-writers, and especially the practitioners, who have approached the subject,have referred in particular to comment and interpretation of existing rules in the Commercial Code and theCivil Procedure Code, not considering the relationship between other institutions of maritime law and seizingthe ship. In our opinion the mentioned institution of law can not be examined thoroughly without priorinvestigation of what is the ship which is subject to seizure. Moreover, the ship is at the heart of all legalresearch on shipping. The concept of ship has been controversial since the seventeenth century, with the firstregulations that led to the development and adoption of commercial codes, and it is still controversial today.We can say that the diversity of opinions, expressed both in the legal literature and legal practice, on theconcept of ship, is largely due to the technical progress of shipping in modern times, this transport meanbenefiting from exceptional facilities to ensure a safely water transport of goods and people.

  4. Ship exhaust gas plume cooling

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Neele, P.P.

    2004-01-01

    The exhaust gas plume is an important and sometimes dominating contributor to the infrared signature of ships. Suppression of the infrared ship signatures has been studied by TNO for the Royal Netherlands Navy over considerable time. This study deals with the suppression effects, which can be achiev

  5. NATO Standards for Virtual Ships

    NARCIS (Netherlands)

    Kraker, J.K. de; Duncan, J.; Budde, E.W.; Reading, R.

    2005-01-01

    The NATO Naval Armaments Group Sub-Group 61 on Virtual Ships has been chartered to establish NATO standards for modeling and simulation applied to ship acquisition. Its objective is to enable multi-national simulation re-use and interoperability, as well as simulation composability. Technical activi

  6. Hydroelastic Vibrations of Ships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Folsø, Rasmus

    2002-01-01

    A formula for the necessary hull girder bending stiffness required to avoid serious springing vibrations is derived. The expression takes into account the zero crossing period of the waves, the ship speed and main dimensions. For whipping vibrations the probability of exceedance for the combined...... wave- and whipping induced bending moment is derived under the assumption that the maximum peak value in a whipping sequence occurs simultaneously with a peak in sagging wave-induced bending moment, but that the magnitudes of these two peaks are statistically independent. The expression can be written...... as the usual Rayleigh distribution for the wave response multiplied by a factor independent of the significant wave height. Finally, the springing and whipping predictions are compared with model test results....

  7. Ship Roll Damping Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2012-01-01

    The technical feasibility of roll motion control devices has been amply demonstrated for over 100 years. Performance, however, can still fall short of expectations because of difficulties associated with control system designs, which have proven to be far from trivial due to fundamental performance...... limitations and large variations of the spectral characteristics of wave-induced roll motion. This tutorial paper presents an account of the development of various ship roll motion control systems together with the challenges associated with their design. It discusses the assessment of performance...... and the applicability of different mathematical models, and it surveys the control methods that have been implemented and validated with full scale experiments. The paper also presents an outlook on what are believed to be potential areas of research within this topic....

  8. Ship of Fools

    OpenAIRE

    Boullet, Vanessa

    2012-01-01

    Ship of Fools est un essai polémique sur les différents éléments qui, selon Fintan O’Toole, ont contribué à la chute du Tigre Celtique : hommes politiques incompétents, souvent corrompus et pourtant réélus par les Irlandais, banquiers et promoteurs cupides, et enfin régulations inexistantes dans la gestion des affaires du pays. La thèse principale que développe O’Toole, journaliste et intellectuel de gauche, est que l’Irlande a d’une certaine manière importé sa modernité économique (passant r...

  9. Occupational accidents aboard merchant ships

    DEFF Research Database (Denmark)

    Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may...... be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...... rate of accidents than Danish citizens. Age was a major risk factor for accidents causing permanent disability. Change of ship and the first period aboard a particular ship were identified as risk factors. Walking from one place to another aboard the ship caused serious accidents. The most serious...

  10. Identification of Dynamically Positioned Ships

    Directory of Open Access Journals (Sweden)

    Thor I. Fossen

    1996-04-01

    Full Text Available Todays model-based dynamic positioning (DP systems require that the ship and thruster dynamics are known with some accuracy in order to use linear quadratic optical control theory. However, it is difficult to identify the mathematical model of a dynamically posititmed (DP ship since the ship is not persistently excited under DP. In addition the ship parameter estimation problem is nonlinear and multivariable with only position and thruster state measurements available for parameter estimation. The process and measurement noise must also be modeled in order to avoid parameter drift due to environmental disturbances and sensor failure. This article discusses an off-line parallel extended Kalman filter (EKF algorithm utilizing two measurement series in parallel to estimate the parameters in the DP ship model. Full-scale experiments with a supply vessel are used to demonstrate the convergence and robustness of the proposed parameter estimator.

  11. A Model of Ship Auxiliary System for Reliable Ship Propulsion

    Directory of Open Access Journals (Sweden)

    Dragan Martinović

    2012-03-01

    Full Text Available The main purpose of a vessel is to transport goods and passengers at minimum cost. Out of the analysis of relevant global databases on ship machinery failures, it is obvious that the most frequent failures occur precisely on the generator-running diesel engines. Any failure in the electrical system can leave the ship without propulsion, even if the main engine is working properly. In that case, the consequences could be devastating: higher running expenses, damage to the ship, oil spill or substantial marine pollution. These are the reasons why solutions that will prevent the ship being unable to manoeuvre during her exploitation should be implemented. Therefore, it is necessary to define a propulsion restoration model which would not depend on the primary electrical energy. The paper provides a model of the marine auxiliary system for more reliable propulsion. This includes starting, reversing and stopping of the propulsion engine. The proposed solution of reliable propulsion model based on the use of a shaft generator and an excitation engine enables the restoration of propulsion following total failure of the electrical energy primary production system, and the self-propelled ship navigation. A ship is an important factor in the Technology of Transport, and the implementation of this model increases safety, reduces downtime, and significantly decreases hazards of pollution damage.KEYWORDSreliable propulsion, failure, ship auxiliary system, control, propulsion restoration

  12. Knowledge Hub y los recursos educativos abiertos en Contaduría

    OpenAIRE

    Farías Martínez, Gabriela María

    2010-01-01

    Desafíos de la educación superior en México; Formación académica y profesional en contaduría; Knowledge Hub como medio para compartir y construir conocimiento; Iniciativa Knowledge Hub IES Contaduría

  13. 14 CFR 158.30 - PFC Authorization at Non-Hub Airports.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false PFC Authorization at Non-Hub Airports. 158... (CONTINUED) AIRPORTS PASSENGER FACILITY CHARGES (PFC'S) Application and Approval § 158.30 PFC Authorization at Non-Hub Airports. (a) General. This section specifies the procedures a public agency controlling...

  14. The Complexities and Challenges of Regional Education Hubs: Focus on Malaysia

    Science.gov (United States)

    Knight, Jane; Morshidi, Sirat

    2011-01-01

    The race to establish regional education hubs is a recent development in cross-border higher education. This article briefly examines the rationales and strategies used by three countries in the Middle East and three in South East Asia which are working towards positioning themselves as regional education hubs. The different approaches and…

  15. Knowledge Hub y los recursos educativos abiertos en Contaduría

    OpenAIRE

    Farías Martínez, Gabriela María

    2013-01-01

    Desafíos de la educación superior en México; Formación académica y profesional en contaduría; Knowledge Hub como medio para compartir y construir conocimiento; Iniciativa Knowledge Hub IES Contaduría

  16. A multi-objective imperialist competitive algorithm for a capacitated hub covering location problem

    Directory of Open Access Journals (Sweden)

    M. Mohammadi

    2011-01-01

    Full Text Available The hub location problem appears in a variety of applications, including airline systems, cargo delivery systems and telecommunication network design. Hub location problems deal with finding the location of hub facilities and the allocation of demand nodes to these located hub facilities. In this paper, a new model for the capacitated single allocation hub covering location problem is presented. Instead of using capacity constraints to limit the amount of flow received by the hubs, the second objective function is introduced to minimize service times in the hubs. The service time in the hubs includes the waiting time of received flows in a queue and the time to get services. Due to the NP-hardness of the problem, a new weight-based multi-objective imperialist competitive algorithm (MOICA is designed to find near-optimal solutions. To validate the performance of the proposed algorithm, the solutions obtained by the MOICA are compared by the exact solutions of the mathematical programming model.

  17. Domestic Output of Aluminium Alloy Hub Surpassing 70 million in 2007

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>According to a report from the hub branch of China Association of Automobile Manufactur- ers,China has produced a total of more than 70 million aluminium alloy hubs in 2007,a year- on-year growth over 25%,while consuming over 700,000 tons of primary aluminium the whole year.

  18. Optimal Scheduling of a Multi-Carrier Energy Hub Supplemented By Battery Energy Storage Systems

    DEFF Research Database (Denmark)

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    This paper introduces a management model for optimal scheduling of a multi-carrier energy hub. In the proposed hub, three types of assets are considered: dispersed generating systems (DGs) such as micro-combined heat and power (mCHP) units, storage devices such as battery-based electrical storage...

  19. Network performance, hub connectivity potential, and competitive position of primary airports in Asia/Pacific region

    NARCIS (Netherlands)

    Matsumoto, H.; Veldhuis, J.; de Wit, J.; Burghouwt, G.

    2008-01-01

    Recently, hub-and-spoke network configurations are more and more developed in the Asia/Pacific region. In this paper, it is argued that the measurement of network performance in hub-and-spoke systems should take into account the quantity and quality of both direct and indirect connections. The NetSc

  20. The Complexities and Challenges of Regional Education Hubs: Focus on Malaysia

    Science.gov (United States)

    Knight, Jane; Morshidi, Sirat

    2011-01-01

    The race to establish regional education hubs is a recent development in cross-border higher education. This article briefly examines the rationales and strategies used by three countries in the Middle East and three in South East Asia which are working towards positioning themselves as regional education hubs. The different approaches and…

  1. Competition and coordination in the U.S. airline hub-to-hub markets: An industry pre-merger case study

    Directory of Open Access Journals (Sweden)

    Prasun Bhattacharjee

    2016-04-01

    Full Text Available Purpose: This paper investigates the nature of conduct that existed in the U.S. airline hub-to-hub markets prior to the recent merger wave of the legacy carriers. We explore the strategic importance of network carrier hubs in form of “spheres of influence” on airline market conduct. We also simultaneously recognize the overgrowing role played by Low Cost Carriers (LCC over the years by estimating two conduct parameters - one in markets where LCCs directly compete head-to-head with legacy carriers and the other for markets which LCCs do not serve but has presence in the hub airports or adjacent airports comprising the market endpoints. Thus our supply side framework also sheds some light on the issue of perfect contestability in airline industry. Design/methodology/approach: We estimate a structural oligopoly model for differentiated products with competitive interactions using DB1B data for first quarter of 2004. Findings: Our results imply that the nature of competition is more aggressive relative to Bertrand behavior in hub-to-hub markets and that these markets are less than perfectly contestable. Originality/value: This paper adds to the empirical literature of airline competition by enabling estimation of the actual conduct parameter assuming firm price setting behavior in presence of product differentiation. Contrary to existing literature on airline competition, a structural model enables us to systematically separate out effects of demand, cost and strategic factors on observed airline prices.

  2. Features analysis for identification of date and party hubs in protein interaction network of Saccharomyces Cerevisiae

    Directory of Open Access Journals (Sweden)

    Araabi Babak N

    2010-12-01

    Full Text Available Abstract Background It has been understood that biological networks have modular organizations which are the sources of their observed complexity. Analysis of networks and motifs has shown that two types of hubs, party hubs and date hubs, are responsible for this complexity. Party hubs are local coordinators because of their high co-expressions with their partners, whereas date hubs display low co-expressions and are assumed as global connectors. However there is no mutual agreement on these concepts in related literature with different studies reporting their results on different data sets. We investigated whether there is a relation between the biological features of Saccharomyces Cerevisiae's proteins and their roles as non-hubs, intermediately connected, party hubs, and date hubs. We propose a classifier that separates these four classes. Results We extracted different biological characteristics including amino acid sequences, domain contents, repeated domains, functional categories, biological processes, cellular compartments, disordered regions, and position specific scoring matrix from various sources. Several classifiers are examined and the best feature-sets based on average correct classification rate and correlation coefficients of the results are selected. We show that fusion of five feature-sets including domains, Position Specific Scoring Matrix-400, cellular compartments level one, and composition pairs with two and one gaps provide the best discrimination with an average correct classification rate of 77%. Conclusions We study a variety of known biological feature-sets of the proteins and show that there is a relation between domains, Position Specific Scoring Matrix-400, cellular compartments level one, composition pairs with two and one gaps of Saccharomyces Cerevisiae's proteins, and their roles in the protein interaction network as non-hubs, intermediately connected, party hubs and date hubs. This study also confirms the

  3. Effective spectral dimension of hub in scale-free networks

    Science.gov (United States)

    Hwang, Sungmin; Lee, Deok-Sun; Kahng, Byungnam

    2012-02-01

    Exploring the World Wide Web has become one of the key issues in information science, specifically in context of its application to the PageRank-like algorithms used in search engine. The random walk approach has been employed to study such a problem. The probability of the return to the origin (RTO) of random walks is inversely related to how information can be accessed during random surfing. We find analytically that the RTO probability for a given starting node shows a crossover from a slow to a fast decay behavior with time and the crossover time increases with the degree of the starting node. Furthermore, the RTO probability is almost constant in the early-time regime as the degree exponent approaches two. This result indicates that a random surfer can be effectively trapped at the hub and supports the necessity of the random jump strategy empirically used in the Google's search engine.

  4. Paneth cells: the hub for sensing and regulating intestinal flora.

    Science.gov (United States)

    Zhang, Zheng; Liu, Zhihua

    2016-05-01

    The complex interplay between symbiotic bacteria and host immunity plays a key role in shaping intestinal homeostasis and maintaining host health. Paneth cells, as one of the major producers of antimicrobial peptides in the intestine under steady-state conditions, play a vital role in regulating intestinal flora. Many studies on inflammatory bowel disease (IBD)-associated genes have put Paneth cells at the center of IBD pathogenesis. In this perspective, we focus on mechanistic studies of different cellular processes in Paneth cells that are regulated by various IBD-associated susceptibility genes, and we discuss the hypothesis that Paneth cells function as the central hub for sensing and regulating intestinal flora in the maintenance of intestinal homeostasis.

  5. A Collaborative Scheduling Model for the Supply-Hub with Multiple Suppliers and Multiple Manufacturers

    Directory of Open Access Journals (Sweden)

    Guo Li

    2014-01-01

    Full Text Available This paper investigates a collaborative scheduling model in the assembly system, wherein multiple suppliers have to deliver their components to the multiple manufacturers under the operation of Supply-Hub. We first develop two different scenarios to examine the impact of Supply-Hub. One is that suppliers and manufacturers make their decisions separately, and the other is that the Supply-Hub makes joint decisions with collaborative scheduling. The results show that our scheduling model with the Supply-Hub is a NP-complete problem, therefore, we propose an auto-adapted differential evolution algorithm to solve this problem. Moreover, we illustrate that the performance of collaborative scheduling by the Supply-Hub is superior to separate decision made by each manufacturer and supplier. Furthermore, we also show that the algorithm proposed has good convergence and reliability, which can be applicable to more complicated supply chain environment.

  6. Hub Identification of the Metro Manila Road Network Using PageRank

    CERN Document Server

    Chan, Jacob

    2016-01-01

    We attempt to identify the different node hubs of a road network using PageRank for preparation for possible random terrorist attacks. The robustness of a road network against such attack is crucial to be studied because it may cripple its connectivity by simply shutting down these hubs. We show the important hubs in a road network based on network structure and propose a model for robustness analysis. By identifying important hubs in a road network, possible preparation schemes may be done earlier to mitigate random terrorist attacks, including defense reinforcement and transportation security. A case study of the Metro Manila road network is also presented. The case study shows that the most important hubs in the Metro Manila road network are near airports, piers, major highways and expressways

  7. A Fractal and Scale-free Model of Complex Networks with Hub Attraction Behaviors

    CERN Document Server

    Kuang, Li; Li, Deyi; Li, Yuanxiang; Sun, Yu

    2013-01-01

    It is widely believed that fractality of complex networks origins from hub repulsion behaviors (anticorrelation or disassortativity), which means large degree nodes tend to connect with small degree nodes. This hypothesis was demonstrated by a dynamical growth model, which evolves as the inverse renormalization procedure proposed by Song et al. Now we find that the dynamical growth model is based on the assumption that all the cross-boxes links has the same probability e to link to the most connected nodes inside each box. Therefore, we modify the growth model by adopting the flexible probability e, which makes hubs have higher probability to connect with hubs than non-hubs. With this model, we find some fractal and scale-free networks have hub attraction behaviors (correlation or assortativity). The results are the counter-examples of former beliefs.

  8. MODELS AND METHODS FOR LOGISTICS HUB LOCATION: A REVIEW TOWARDS TRANSPORTATION NETWORKS DESIGN

    Directory of Open Access Journals (Sweden)

    Carolina Luisa dos Santos Vieira

    Full Text Available ABSTRACT Logistics hubs affect the distribution patterns in transportation networks since they are flow-concentrating structures. Indeed, the efficient moving of goods throughout supply chains depends on the design of such networks. This paper presents a literature review on the logistics hub location problem, providing an outline of modeling approaches, solving techniques, and their applicability to such context. Two categories of models were identified. While multi-criteria models may seem best suited to find optimal locations, they do not allow an assessment of the impact of new hubs on goods flow and on the transportation network. On the other hand, single-criterion models, which provide location and flow allocation information, adopt network simplifications that hinder an accurate representation of the relationshipbetween origins, destinations, and hubs. In view of these limitations we propose future research directions for addressing real challenges of logistics hubs location regarding transportation networks design.

  9. Electricity hubs and market centers: A new business tool for electric utilities?

    Energy Technology Data Exchange (ETDEWEB)

    Vallen, M.A.; Sharp, L.S. [Univ. of Toledo, OH (United States)

    1995-07-01

    There are many complexities clouding the use of hubs and market centers in the electricity market, but lessons learned in the natural gas industry can save a lot of unnecessary reinvention. The bottom line: Electricity hubs and market centers will allow the markets to work most efficiently. This article will describe how regional trading hubs may function in the competitive electricity market, using the experiences of the natural gas market to illustrate the principles involved. Part I will define the typical characteristics of hubs and market centers and describe the dey success factors needed to develop a new market center. Part II will describe the types of products and services that an electricity hub or marketing center will need to offer to succeed.

  10. USDA Southwest Regional Hub for Adaptation to and Mitigation of Climate Change

    Science.gov (United States)

    Rango, A.; Elias, E.; Steele, C. M.; Havstad, K.

    2014-12-01

    The USDA Southwest (SW) Climate Hub was created in February 2014 to develop risk adaptation and mitigation strategies for coping with climate change effects on agricultural productivity. There are seven regional hubs across the country with three subsidiary hubs. The SW Climate Hub Region is made up of six states: New Mexico, Arizona, Utah, Nevada, California and Hawaii (plus the Trust Territories of the Pacific Islands). The SW Climate Hub has a subsidiary hub located in Davis, California. The Southwest region has high climatic diversity, with the lowest and highest average annual rainfall in the U.S.(6.0 cm in Death Valley, CA and 1168 cm at Mt. Waialeale, HI). There are major deserts in five of the six states, yet most of the states, with exception of Hawaii, depend upon the melting of mountain snowpacks for their surface water supply. Additionally, many of the agricultural areas of the SW Regional Hub depend upon irrigation water to maintain productivity. Scientific climate information developed by the Hub will be used for climate-smart decision making. To do this, the SW Regional Hub will rely upon existing infrastructure of the Cooperative Extension Service at Land-Grant State Universities. Extension service and USDA-NRCS personnel have existing networks to communicate with stakeholders (farmers, ranchers, and forest landowners) through meetings and workshops which have already started in the six states. Outreach through the development of a weather and climate impact modules designed for seventh grade students and their teachers will foster education of future generations of rural land managers. We will be synthesizing and evaluating existing reports, literature and information on regional climate projections, water resources, and agricultural adaptation strategies related to climate in the Southwest. The results will be organized in a spatial format and provided through the SW Hub website (http://swclimatehub.info) and peer-reviewed articles.

  11. The noise generated by a landing gear wheel with hub and rim cavities

    Science.gov (United States)

    Wang, Meng; Angland, David; Zhang, Xin

    2017-03-01

    Wheels are one of the major noise sources of landing gears. Accurate numerical predictions of wheel noise can provide an insight into the physical mechanism of landing gear noise generation and can aid in the design of noise control devices. The major noise sources of a 33% scaled isolated landing gear wheel are investigated by simulating three different wheel configurations using high-order numerical simulations to compute the flow field and the FW-H equation to obtain the far-field acoustic pressures. The baseline configuration is a wheel with a hub cavity and two rim cavities. Two additional simulations are performed; one with the hub cavity covered (NHC) and the other with both the hub cavity and rim cavities covered (NHCRC). These simulations isolate the effects of the hub cavity and rim cavities on the overall wheel noise. The surface flow patterns are visualised by shear stress lines and show that the flow separations and attachments on the side of the wheel, in both the baseline and the configuration with only the hub cavity covered, are significantly reduced by covering both the hub and rim cavities. A frequency-domain FW-H equation is used to identify the noise source regions on the surface of the wheel. The tyre is the main low frequency noise source and shows a lift dipole and side force dipole pattern depending on the frequency. The hub cavity is identified as the dominant middle frequency noise source and radiates in a frequency range centered around the first and second depth modes of the cylindrical hub cavity. The rim cavities are the main high-frequency noise sources. With the hub cavity and rim cavities covered, the largest reduction in Overall Sound Pressure Level (OASPL) is achieved in the hub side direction. In the other directivities, there is also a reduction in the radiated sound.

  12. Failure analysis of retrieved PE-UHMW acetabular liners.

    Science.gov (United States)

    Laska, Anna; Archodoulaki, Vasiliki-Maria; Duscher, Bernadette

    2016-08-01

    Ultra-high molecular weight polyethylene (PE-UHMW) acetabular liners have a limited lifespan in a patient's body. There are many factors affecting the performance of the implant and furthermore the properties of the polymeric material are changing after implantation. In this work material changes according to structure and morphology and their implication on mechanical properties are in focus. The physical and mechanical properties of ten crosslinked (xL) PE-UHMW and nine conventional (conv) gamma-sterilized PE-UHMW hip components, used as sliding surface in total hip joint replacement, with different in-vivo times are compared. The evaluation of the retrieved acetabular liners is performed in view of crosslinking and conventional gamma-sterilization but also in terms of the influence of gender concerning alteration in properties. The oxidative degradation in the PE-UHMW is investigated by means of Fourier Transformed Infrared Spectroscopy (FTIR). The characterization of the morphology is carried out via differential scanning calorimetry (DSC). A depth profile of the micro-hardness and elastic modulus is taken over the cross-section of the components in order to find the influence of chemical constitution and morphology on the micro-mechanical properties. It could be shown that crosslinking and oxidative degradation influence the degree of crystallinity of the polymer. Oxidation occurs for both types of the material due to in-vivo time. Higher degree of crystallinity can be correlated to higher hardness and indentation modulus. No unequivocal superiority of crosslinked over conventional liners can be observed. The influence of sex concerning alteration of the evaluated properties matters but need to be further investigated.

  13. Case histories : implementation of new liner hanger technology in south central Venezuela significantly improves operations in complex wells

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, C.; Soto, S.; Leon, A. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of); Marval, P.; Schoener-Scott, M. [Halliburton, Houston, TX (United States)

    2009-07-01

    Liner hangers are used in deep drilling operations to eliminate the need for full casing strings. However, conventional liner-hanger system do not always permit tool rotation, and liner-hanger failures can result in the complete loss of the wellbore. This study discussed an expandable liner hanger designed to withstand aggressive reaming as well as drilling to depths. Three case histories of wells located in southern Venezuela were used to compare the use of traditional and expandable liner hanger systems. The studies considered liner weight, and the pressure differentials caused by the use of positive seals. The study showed that conventional liner systems are not suited to the extreme environments of the Venezuelan heavy oil reserves. Multiple leak paths were observed. The expandable liner system provided a gas-tight seal, improved flow paths, and reduced the need for remedial cement jobs. It was concluded that use of the expandable systems also increased worker safety. 6 refs., 13 figs.

  14. Refractory Metal Liner Processing for M242 Medium Caliber Barrels

    Science.gov (United States)

    2013-01-01

    tapping a hole in the top end of the load rod. 6 3. Liner and Barrel Dimensions Several GLEEM experiments had previously been conducted with a...the load rod had been inserted with tapped end next to the elastomer, which extruded into the hole. During the next pass with the 20-in load rod, the...Load release occurred at a rate of 15 kip/min. The gun tube was then inverted and a fifth pass attempted. For this pass, straps were applied to the

  15. Production Balance of Ship Erection

    Institute of Scientific and Technical Information of China (English)

    JIANG Ru-hong; TAN Jia-hua; LIU Cun-gen

    2008-01-01

    A network plan model of ship erection was established based on the network planning technologyand the work-package breakdown system. The load-oriented production control method was introduced to buildup a throughput diagram model thus it is possible to describe the ship erection process numerically. Based onthe digitaiized models some cases of production balance of ship erection were studied and three balance indexeswere put forward, they are the load balance rate, the input manpower balance rate and the maximum gantrycrane operating times. Such an analytic method based on the balance evaluation is the important foundationfor digitization and intelligentization of shipyard production management.

  16. Neutrino physics with SHIP

    CERN Document Server

    van Herwijnen, Eric

    2016-01-01

    SHIP is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee. It recommended that the experiment proceed further to a Comprehensive Design phase. In its initial phase, the 400 GeV proton beam extracted from the SPS will be dumped on a heavy target with the aim of integrating 2×1020 POT (Protons On Target) in 5 years. A dedicated detector, based on a long vacuum tank followed by a spectrometer and particle identification detectors, will allow probing a variety of models with light long-lived exotic particles and masses below O(10) GeV/c 2 . The main focus will be the physics of the so-called Hidden Portals. The sensitivity to Heavy Neutrinos will allow to probe for the first time the mass range between the kaon and the charm meson mass, and a range of couplings for which Baryogenesis and active neutrino masses could also be explained. Another dedicated detector will allow the study of neutrino cross-sections and angular distributions. ντ ...

  17. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    Science.gov (United States)

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

  18. Evaluation of a Variable-Impedance Ceramic Matrix Composite Acoustic Liner

    Science.gov (United States)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2014-01-01

    As a result of significant progress in the reduction of fan and jet noise, there is growing concern regarding core noise. One method for achieving core noise reduction is via the use of acoustic liners. However, these liners must be constructed with materials suitable for high temperature environments and should be designed for optimum absorption of the broadband core noise spectrum. This paper presents results of tests conducted in the NASA Langley Liner Technology Facility to evaluate a variable-impedance ceramic matrix composite acoustic liner that offers the potential to achieve each of these goals. One concern is the porosity of the ceramic matrix composite material, and whether this might affect the predictability of liners constructed with this material. Comparisons between two variable-depth liners, one constructed with ceramic matrix composite material and the other constructed via stereolithography, are used to demonstrate this material porosity is not a concern. Also, some interesting observations are noted regarding the orientation of variable-depth liners. Finally, two propagation codes are validated via comparisons of predicted and measured acoustic pressure profiles for a variable-depth liner.

  19. Evaluation of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    Science.gov (United States)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2015-01-01

    This paper explores the effects of variable-depth geometry on the amount of noise reduction that can be achieved with acoustic liners. Results for two variable-depth liners tested in the NASA Langley Grazing Flow Impedance Tube demonstrate significant broadband noise reduction. An impedance prediction model is combined with two propagation codes to predict corresponding sound pressure level profiles over the length of the Grazing Flow Impedance Tube. The comparison of measured and predicted sound pressure level profiles is sufficiently favorable to support use of these tools for investigation of a number of proposed variable-depth liner configurations. Predicted sound pressure level profiles for these proposed configurations reveal a number of interesting features. Liner orientation clearly affects the sound pressure level profile over the length of the liner, but the effect on the total attenuation is less pronounced. The axial extent of attenuation at an individual frequency continues well beyond the location where the liner depth is optimally tuned to the quarter-wavelength of that frequency. The sound pressure level profile is significantly affected by the way in which variable-depth segments are distributed over the length of the liner. Given the broadband noise reduction capability for these liner configurations, further development of impedance prediction models and propagation codes specifically tuned for this application is warranted.

  20. Characteristics of Sulfuric Acid Condensation on Cylinder Liners of Large Two-Stroke Marine Engines

    DEFF Research Database (Denmark)

    Cordtz, Rasmus Lage; Mayer, Stefan; Schramm, Jesper;

    The present work seeks to clarify the characteristics of sulfuric acid condensation on the cylinder liner of a large two–stroke marine engine. The liner is directly exposed to the cylin-der gas (i.e. no protective lube oil film) and is represented by a constant temperature over the full stroke...

  1. Recyclability of mixed office waste papers containing pressure sensitive adhesives and silicone release liners

    Science.gov (United States)

    Julie Hess; Roberta Sena-Gomes; Lisa Davie; Marguerite Sykes

    2001-01-01

    Increased use of pressure sensitive adhesives for labels and stamps has introduced another contaminant into the office paper stream: silicone- coated release liners. This study examines methods and conditions for removal of contaminants, including these liners, from a typical batch of discarded office papers. Removal of contaminants contained in the furnish were...

  2. Imaging of ceramic liner fractures in total hip arthroplasty: the value of CT

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Yoshimi; Mintz, Douglas N. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States); Renner, Lisa; Schmidt-Braekling, Tom; Boettner, Friedrich [Hospital for Special Surgery, Adult Reconstruction and Joint Replacement Division, New York, NY (United States)

    2015-08-15

    Fracture of a ceramic liner of a total hip arthroplasty is rare and is radiographically occult if not displaced. We report on two patients in whom ceramic liner fracture was radiographically occult but was diagnosed on subsequent CT scan through appropriate windowing. (orig.)

  3. Field-scale investigation of infiltration into a compacted soil liner

    Science.gov (United States)

    Panno, Samuel V.; Herzog, Beverly L.; Cartwright, Keros; Rehfeldt, Kenneth R.; Krapac, Ivan G.; Hensel, Bruce R.

    1991-01-01

    The Illinois State Geological Survey constructed and instrumented an experimental compacted soil liner. Infiltration of water into the liner has been monitored for two years. The objectives of this investigation were to determine whether a soil liner could be constructed to meet the U.S. EPA's requirement for a saturated hydraulic conductivity of less than or equal to 1.0 ?? 10-7 cm/s, to quantify the areal variability of the hydraulic properties of the liner, and to determine the transit time for water and tracers through the liner. The liner measures 8m ?? 15m ?? 0.9m and was designed and constructed to simulate compacted soil liners built at waste disposal facilities. The surface of the liner was flooded to form a pond on April 12, 1988. Since flooding, infiltration has been monitored with four large-ring (LR) and 32 small-ring (SR) infiltrometers, and a water-balance (WB) method that accounted for total infiltration and evaporation. Ring-infiltrometer and WB data were analyzed using cumulative-infiltration curves to determine infiltration fluxes. The SR data are lognormally distributed, and the SR and LR data form two statistically distinct populations. Small-ring data are nearly identical with WB data; because there is evidence of leakage in the LRs, the SR and WB data are considered more reliable.

  4. Leakage performance of the GM + CCL liner system for the MSW landfill.

    Science.gov (United States)

    Jingjing, Fan

    2014-01-01

    The contaminants in the landfill leachate press pose a grave threat to environment of the soil and the groundwater beneath the landfill. Despite there being strict requirements in relevant provisions of both domestic and foreign countries for the design of the bottom liner system. Pollution of the soil and the groundwater still took place in a number of landfills because of the leakage. To investigate the leakage rate of the liner systems, the minimum design requirements of the liner systems are summarized according to the provisions of four countries, including China, USA, Germany, and Japan. Comparative analyses using one-dimensional transport model are conducted to study the leakage performance of these liner systems composed of geomembrance (GM) and compacted clay layer (CCL) meeting the relevant minimum design requirements. Then parametric analyses are conducted to study the effects of the hydraulic head, the thickness of GM, the hydraulic conductivity of CCL, and so forth on the leakage performance of the liner system. It is concluded that the liner system designed according to the minimum design requirements of Germany provide the best antileakage performance, while that of Japan performs the lowest. The key parameters affecting the failure time of the liner system are summarized. Finally, some suggestions for the design of the liner systems are made according to the analyses.

  5. Leakage Performance of the GM + CCL Liner System for the MSW Landfill

    Directory of Open Access Journals (Sweden)

    Fan Jingjing

    2014-01-01

    Full Text Available The contaminants in the landfill leachate press pose a grave threat to environment of the soil and the groundwater beneath the landfill. Despite there being strict requirements in relevant provisions of both domestic and foreign countries for the design of the bottom liner system. Pollution of the soil and the groundwater still took place in a number of landfills because of the leakage. To investigate the leakage rate of the liner systems, the minimum design requirements of the liner systems are summarized according to the provisions of four countries, including China, USA, Germany, and Japan. Comparative analyses using one-dimensional transport model are conducted to study the leakage performance of these liner systems composed of geomembrance (GM and compacted clay layer (CCL meeting the relevant minimum design requirements. Then parametric analyses are conducted to study the effects of the hydraulic head, the thickness of GM, the hydraulic conductivity of CCL, and so forth on the leakage performance of the liner system. It is concluded that the liner system designed according to the minimum design requirements of Germany provide the best antileakage performance, while that of Japan performs the lowest. The key parameters affecting the failure time of the liner system are summarized. Finally, some suggestions for the design of the liner systems are made according to the analyses.

  6. Cementing constrained acetabular liners in revision hip replacement: clinical and laboratory observations.

    Science.gov (United States)

    Mountney, John; Garbuz, Donald S; Greidanus, Nelson V; Masri, Bassam A; Duncan, Clive P

    2004-01-01

    During revision hip arthroplasty, removal of a well-fixed, ingrown metal acetabular component may not be possible. Therefore, a new polyethylene liner can be cemented into the existing shell via the cement locking mechanism. This technique is well recognized, and the cement locking mechanism has proved to be sufficiently strong and durable for clinical use. A constrained polyethylene liner is designed to reduce the risk of hip dislocation by capturing the femoral head. However, there are increased shear forces created at the liner interface as the dislocation is resisted. If a constrained liner is cemented into an ingrown acetabular component, then there is the theoretical risk that these increased shear forces will damage the cement locking mechanism, thus leading to failure of the construct. There are a few clinical series in which a constrained liner has been used with the cement locking mechanism. Overall, the failure rate of the cement locking mechanism is no greater if a constrained liner instead of a standard liner is used. The cement locking mechanism can be strengthened by roughening the backside of a smooth polyethylene liner to improve the cement-polyethylene interface, or by using an all-polyethylene acetabular component that is designed to be used with cement. Whether a smooth metal shell needs to be roughened as well is a matter of debate.

  7. 75 FR 1596 - Grant of Authority for Subzone Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock...

    Science.gov (United States)

    2010-01-12

    ... Register (74 FR 14956, 4-2-2009) and the application has been processed pursuant to the FTZ Act and the... (Aluminum Foil Liner Stock), Louisville, Kentucky Pursuant to its authority under the Foreign-Trade Zones... to the Board for authority to establish a special-purpose subzone at the aluminum foil liner...

  8. Effect of Additives on Liner Properties of Case-bonded Composite Propellants

    Directory of Open Access Journals (Sweden)

    S. B. Navale

    2004-07-01

    Full Text Available A thin layer of liner is applied to ensure a good bond between the insulator and the propellant in case-bonded rocket motors. It also acts as a protective shield for the insulatorby providing a limited fire protection effect. Liner compositions should preferably be based on the same binder system used in the propellant formulations. As the liner has to hold the propellant and the insulator without debond under all the environmental conditions, it plays a key role in predicted performance of a rocket motor. Hence, studies were carried out to improve the liner properties using various hydroxyl compounds, such as butanediol, cardanol, trimethylol propane, pyrogallol, etc as additives. Butanediol and phloroglucinol combination gave the best results in terms of mechanical properties and interface properties for the liner compositions. The effect of filler content on the liner properties was also studied. The results showed that higher filler content does not affect interface properties. Considering the fire retardancy effect and reinforcement of antimony trioxide (S£203, the formulation containing higher Sb2O3 was selected. The studies on pot life/castable life of liner showed that propellant could be cast up to 6 days after liner coating, without adversely affecting the bonding and the bond strength.

  9. Performance evaluation of a newly developed variable rate sprayer for nursery liner applications

    Science.gov (United States)

    An experimental variable-rate sprayer designed for liner applications was tested by comparing its spray deposit, coverage, and droplet density inside canopies of six nursery liner varieties with constant-rate applications. Spray samplers, including water sensitive papers (WSP) and nylon screens, wer...

  10. Modeling of Broadband Liners Applied to the Advanced Noise Control Fan

    Science.gov (United States)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2015-01-01

    The broadband component of fan noise has grown in relevance with an increase in bypass ratio and incorporation of advanced fan designs. Therefore, while the attenuation of fan tones remains a major factor in engine nacelle acoustic liner design, the simultaneous reduction of broadband fan noise levels has received increased interest. As such, a previous investigation focused on improvements to an established broadband acoustic liner optimization process using the Advanced Noise Control Fan (ANCF) rig as a demonstrator. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom liner designs were carried through design, fabrication, and testing. This paper addresses a number of areas for further research identified in the initial assessment of the ANCF study. Specifically, incident source specification and uncertainty in some aspects of the predicted liner impedances are addressed. This information is incorporated in updated predictions of the liner performance and comparisons with measurement are greatly improved. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of various liner designs. This study also provides further confidence in the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  11. Gas Turbine Combustor Liner Life Assessment Using a Combined Fluid/Structural Approach

    NARCIS (Netherlands)

    Tinga, Tiedo; Kampen, van J.F.; Jager, de B.; Kok, J.B.W.

    2007-01-01

    A life assessment was performed on a fighter jet engine annular combustor liner, using a combined fluid/structural approach. Computational fluid dynamics analyses were performed to obtain the thermal loading of the combustor liner and finite element analyses were done to calculate the temperature an

  12. Slagging characteristics of molten coal ash on silicon-aluminum combustion liners of boiler

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to study the slagging characteristics of boiler combustion liners during pulverized coal stream combustion,the slag samples on the surface of combustion liner were investigated by X-ray diffractometry,scan electron microscopy and energy dispersive X-ray analysis,and the transformation characteristics of the compositions and crystal phases were studied.The results show that the size of slag granules decreases as the slagging temperature increases;the crystallinity of coal ash I reduces to about 48.6% when the temperature is increased up to 1 350 ℃,and that of the coal ash Ⅱ reduces to about 65% when the temperature is increased up to 1 500 ℃;the encroachment of molten coal ash to the combustion liner is strengthened.At the same time,the diffusion and the segregation of the compositions in combustion liners have selectivity,which is in favor of enhancing the content of crystal phases,weakening the conglutination among molten slag compositions and combustion liner,and avoiding yielding big clinkers.But the diffusion of the compositions in combustion liners increases the porosity and decreases the mechanical intensity of combustion liner,and makes the slag encroachment to the liner become more serious.

  13. Testing of elastomeric liners used in limb prosthetics: classification of 15 products by mechanical performance.

    Science.gov (United States)

    Sanders, Joan E; Nicholson, Brian S; Zachariah, Santosh G; Cassisi, Damon V; Karchin, Ari; Fergason, John R

    2004-03-01

    The mechanical properties of 15 elastomeric liner products used in limb prosthetics were evaluated under compressive, frictional, shear, and tensile loading conditions. All testing was conducted at load levels comparable to interface stress measurements reported on transtibial amputee subjects. For each test configuration, materials were classified into four groups based on the shapes of their response curves. For the 15 liners tested, there were 10 unique classification sets, indicating a wide range of unique materials. In general, silicone gel liners classified within the same groups thus were quite similar to each other. They were of lower compressive, shear, and tensile stiffness than the silicone elastomer products, consistent with their lightly cross-linked, high-fluid content structures. Silicone elastomer products better spanned the response groups than the gel liners, demonstrating a wide range of compressive, shear, and tensile stiffness values. Against a skin-like material, a urethane liner had the highest coefficient of friction of any liner tested, although coefficients of friction values for most of the materials were higher than interface shear:pressure ratios measured on amputee subjects using Pelite liners. The elastomeric liner material property data and response groupings provided here can potentially be useful to prosthetic fitting by providing quantitative information on similarities and differences among products.

  14. Optimization of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    Science.gov (United States)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Schiller, N. H.; Born, J. C.

    2016-01-01

    This paper employs three acoustic propagation codes to explore variable-depth liner configurations for the NASA Langley Grazing Flow Impedance Tube (GFIT). The initial study demonstrates that a variable impedance can acceptably be treated as a uniform impedance if the spatial extent over which this variable impedance occurs is less than one-third of a wavelength of the incident sound. A constrained optimization study is used to design a variable-depth liner and to select an optimization metric. It also provides insight regarding how much attenuation can be achieved with variable-depth liners. Another optimization study is used to design a liner with much finer chamber depth resolution for the Mach 0.0 and 0.3 test conditions. Two liners are designed based on spatial rearrangement of chambers from this liner to determine whether the order is critical. Propagation code predictions suggest this is not the case. Both liners are fabricated via additive manufacturing and tested in the GFIT for the Mach 0.0 condition. Predicted and measured attenuations compare favorably across the full frequency range. These results clearly suggest that the chambers can be arranged in any order, thus offering the potential for innovative liner designs to minimize depth and weight.

  15. Field performance assessment of synthetic liners for uranium tailings ponds: a status report

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, D.H.; Spanner, G.E.

    1984-03-01

    The objective of this study is to provide a database to support US Nuclear Regulatory Commission (NRC) licensing of uranium tailings leachate isolation impoundments. This objective is being accomplished by determining the effectiveness of design, installation, and quality assurance practices associated with uranium mill tailings impoundments with flexible membrane liners. The program includes testing of chemical resistance and physical performance of liners, leak detection systems, and seam inspection techniques. This report presents the status of the program through September 1983. The report addresses impoundment design, installation, and inspection techniques used by the uranium milling industry. To determine the relative successes of these techniques, information has been collected from consultants, mill operators, and the synthetic liner industry. Progress in experimental tasks on chemical resistance of liners, physical properties of liners, and nondestructive examination of seams is reported. 25 references, 9 figures, 13 tables.

  16. Investigation into the replacement of conventional support with spray-on liners

    Energy Technology Data Exchange (ETDEWEB)

    Espley, S.J.; Denis, J.; O`Donnell, P.; Thibodeau, D.; Paradis-Sokoloski, P. [INCO Limited, Copper Cliff, ON (Canada). Mines Research Department

    1996-06-01

    The results of shotcrete spray-on liner trials at Stobie Mine and of Mineguard polyurethane spray-on trials at Lower Coleman Mine are described. The Stobie trial, which is a continuation of an earlier study, examines the support function under dynamic conditions of boltless, shotcrete liner in a sublevel heading. Steel fibres were used in place of the screen-reinforced shotcrete used in the earlier trial. The overall support capabilities and the resistance to blasting conditions during mining are discussed. The second trial evaluates the Mineguard spray-on liner for replacing conventional support at three underground sites. The results show the liner has a very specific support mechanism, different from that of shotcrete liners. 12 refs., 7 figs.

  17. Effect of microseparation and third-body particles on dual-mobility crosslinked hip liner wear.

    Science.gov (United States)

    Netter, Jonathan D; Hermida, Juan C; Chen, Peter C; Nevelos, James E; D'Lima, Darryl D

    2014-09-01

    Large heads have been recommended to reduce the risk of dislocation after total hip arthroplasty. One of the issues with larger heads is the risk of increased wear and damage in thin polyethylene liners. Dual-mobility liners have been proposed as an alternative to large heads. We tested the wear performance of highly crosslinked dual-mobility liners under adverse conditions simulating microseparation and third-body wear. No measurable increase in polyethylene wear rate was found in the presence of third-body particles. Microseparation induced a small increase in wear rate (2.9mm(3)/million cycles). A finite element model simulating microseparation in dual-mobility liners was validated using these experimental results. The results of our study indicate that highly crosslinked dual-mobility liners have high tolerance for third-body particles and microseparation.

  18. Reaching High-Yield Fusion with a Slow Plasma Liner Compressing a Magnetized Target

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D D; Parks, P B

    2008-03-18

    Dynamics of the compression of a magnetized plasma target by a heavy liner made of partially ionized high high-Z material is discussed. A 'soft-landing' (shockless) mode of the liner deceleration is analyzed. Conclusion is drawn that such mode is possible for the liners whose thickness at the time of the first contact with the target is smaller than, roughly, 10% of the initial (un-compressed) target radius. A combination of the plasma liner with one or two glide cones allows for a direct access to the area near the center of the reactor chamber. One can then generate plasma target inside the plasma liner at the optimum time. The other advantage of the glide cones is that they can be used to deliver additional fuel to the center of the target near the point of a maximum compression and thereby increase the fusion yield.

  19. The origins of liner material in a shaped charge jet particle

    Energy Technology Data Exchange (ETDEWEB)

    Zernow, L. (Zernow Technical Services, Inc., San Dimas, CA (United States)); Chapyak, E.J.; Meyer, K.A. (Los Alamos National Lab., NM (United States)); Zernow, R.H. (Applied Research Associates, Inc., Lakewood, CO (United States))

    1992-01-01

    An improved high resolution LaGrangean tracer particle technique (using 198 identified tracer particles arranged as 99 particle pairs) has been used with an Eulerian Code (MESA 2D) to determine the locations in the jet to which liner material flows from various tagged locations in the liner, during the collapse, jet formation and jet stretching process. Time dependent strain and strain rate data has been computed, using the identified particle pairs of LaGrangean tracer particles as linear strain gauges. Sharp radial gradients of strain and strain rate have been found in the jet, with the liner material flowing nearest the jet axis being subjected to the highest strains and strain rates. Liner material from many extended initial locations along the liner can be traced by this method to jet locations corresponding to individual jet particles. The new quantitative data derived is illustrated with selected examples whose interpretation is discussed.

  20. The origins of liner material in a shaped charge jet particle

    Energy Technology Data Exchange (ETDEWEB)

    Zernow, L. [Zernow Technical Services, Inc., San Dimas, CA (United States); Chapyak, E.J.; Meyer, K.A. [Los Alamos National Lab., NM (United States); Zernow, R.H. [Applied Research Associates, Inc., Lakewood, CO (United States)

    1992-02-01

    An improved high resolution LaGrangean tracer particle technique (using 198 identified tracer particles arranged as 99 particle pairs) has been used with an Eulerian Code (MESA 2D) to determine the locations in the jet to which liner material flows from various tagged locations in the liner, during the collapse, jet formation and jet stretching process. Time dependent strain and strain rate data has been computed, using the identified particle pairs of LaGrangean tracer particles as linear strain gauges. Sharp radial gradients of strain and strain rate have been found in the jet, with the liner material flowing nearest the jet axis being subjected to the highest strains and strain rates. Liner material from many extended initial locations along the liner can be traced by this method to jet locations corresponding to individual jet particles. The new quantitative data derived is illustrated with selected examples whose interpretation is discussed.

  1. WMO Selected, Supplemenatary, Auxiliary Ships

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Meteorological Organization International List of Selected, Supplementary and Auxiliary Ships, recognized as Publication 47. 1973-1998 editions, gathered from...

  2. Modeling of the electric ship

    OpenAIRE

    2010-01-01

    Approved for public release; distribution is unlimited As the United States Navy continues to refine its designs for future ships, one approach that it is currently being explored is to use a unified electrical grid to power every system aboard a ship, including propulsion and weapons. Some concerns with this design are estimating the power demands placed upon the grid by various systems and anticipating transients induced on the grid by high power pulsed loads. The first part of this thes...

  3. Littoral Combat Ship Crew Scheduling

    Science.gov (United States)

    2015-03-01

    package DON Department of the Navy F&R Fix and Relax GAMS General Algebraic Modeling System LCS Littoral Combat Ship LCSRON Littoral Combat Ship...but that can be acceptable depending on the scheduler needs. F&R produces superior long-term schedules when compared to a similar-length RH schedule...LEFT BLANK 29 IV. MODEL IMPLEMENTATION LCSS is implemented with the General Algebraic Modeling System (GAMS) using the GAMS/CPLEX (GAMS, 2014

  4. Lifecycle Readiness and Ship Deployment

    Science.gov (United States)

    2013-06-01

    The physical fatigue associated with ship motions has significant consequences for today’s minimally manned ships. “Because of minimally sized...a deployment. The inefficiencies in performance may develop from lack of training, different personal aptitude, and individual’s mental or physical ...exacerbation of symptoms known as the avalanche phenomenon follows which includes: increased salivation, bodily warmth , and light- headedness” (Stevens

  5. Clinical performance of Class I nanohybrid composite restorations with resin-modified glass-ionomer liner and flowable composite liner: A randomized clinical trial

    Science.gov (United States)

    Suhasini, Krishtipati; Madhusudhana, Koppolu; Suneelkumar, Chinni; Lavanya, Anumula; Chandrababu, K. S.; Kumar, Perisetty Dinesh

    2016-01-01

    Background: Liners play a vital role in minimizing polymerization shrinkage stress by elastic bonding concept and increase the longevity and favorable outcome for composite restorations. Aims: The aim of this study was to evaluate the clinical performance of nanohybrid composite restorations using resin-modified glass-ionomer and flowable composite liners. Settings and Design: A single-centered, double-blinded randomized clinical trial, with split-mouth design and equal allocation ratio that was conducted in the Department of Conservative Dentistry and Endodontics. Materials and Methods: In forty patients, a total of eighty Class I restorations were placed with resin-modified glass-ionomer cement (RMGIC) liner (FUJI II LC, GC America) in one group and flowable composite liner (smart dentin replacement/SDR, Dentsply Caulk, Milford, DE, USA) in another group. All restorations were clinically evaluated by two examiners, immediately (baseline), 3, 6, and 12 months using US Public Health Service modified criteria. Statistical Analysis Used: Statistical analysis was performed using McNemar's test (P < 0.05). Results: There was no significant difference in the color match, marginal discoloration, surface roughness, and marginal adaptation. Restorations with RMGIC liner group show 20% Bravo scores on anatomic form at 12 months but are still clinically acceptable. Conclusion: Nanohybrid composite restorations with RMGIC (Fuji II LC) and flowable composite liner (SDR) demonstrated clinically acceptable performance after 12 months. PMID:27994310

  6. Connectome hubs at resting state in children and adolescents: Reproducibility and psychopathological correlation

    Directory of Open Access Journals (Sweden)

    João Ricardo Sato

    2016-08-01

    Full Text Available Functional brain hubs are key integrative regions in brain networks. Recently, brain hubs identified through resting-state fMRI have emerged as interesting targets to increase understanding of the relationships between large-scale functional networks and psychopathology. However, few studies have directly addressed the replicability and consistency of the hub regions identified and their association with symptoms. Here, we used the eigenvector centrality (EVC measure obtained from graph analysis of two large, independent population-based samples of children and adolescents (7–15 years old; total N = 652; 341 subjects for site 1 and 311 for site 2 to evaluate the replicability of hub identification. Subsequently, we tested the association between replicable hub regions and psychiatric symptoms. We identified a set of hubs consisting of the anterior medial prefrontal cortex and inferior parietal lobule/intraparietal sulcus (IPL/IPS. Moreover, lower EVC values in the right IPS were associated with psychiatric symptoms in both samples. Thus, low centrality of the IPS was a replicable sign of potential vulnerability to mental disorders in children. The identification of critical and replicable hubs in functional cortical networks in children and adolescents can foster understanding of the mechanisms underlying mental disorders.

  7. Connectome hubs at resting state in children and adolescents: Reproducibility and psychopathological correlation.

    Science.gov (United States)

    Sato, João Ricardo; Biazoli, Claudinei Eduardo; Salum, Giovanni Abrahão; Gadelha, Ary; Crossley, Nicolas; Vieira, Gilson; Zugman, André; Picon, Felipe Almeida; Pan, Pedro Mario; Hoexter, Marcelo Queiroz; Anés, Mauricio; Moura, Luciana Monteiro; Del'Aquilla, Marco Antonio Gomes; Junior, Edson Amaro; Mcguire, Philip; Rohde, Luis Augusto; Miguel, Euripedes Constantino; Bressan, Rodrigo Affonseca; Jackowski, Andrea Parolin

    2016-08-01

    Functional brain hubs are key integrative regions in brain networks. Recently, brain hubs identified through resting-state fMRI have emerged as interesting targets to increase understanding of the relationships between large-scale functional networks and psychopathology. However, few studies have directly addressed the replicability and consistency of the hub regions identified and their association with symptoms. Here, we used the eigenvector centrality (EVC) measure obtained from graph analysis of two large, independent population-based samples of children and adolescents (7-15 years old; total N=652; 341 subjects for site 1 and 311 for site 2) to evaluate the replicability of hub identification. Subsequently, we tested the association between replicable hub regions and psychiatric symptoms. We identified a set of hubs consisting of the anterior medial prefrontal cortex and inferior parietal lobule/intraparietal sulcus (IPL/IPS). Moreover, lower EVC values in the right IPS were associated with psychiatric symptoms in both samples. Thus, low centrality of the IPS was a replicable sign of potential vulnerability to mental disorders in children. The identification of critical and replicable hubs in functional cortical networks in children and adolescents can foster understanding of the mechanisms underlying mental disorders.

  8. Incremental Optimization of Hub and Spoke Network for the Spokes’ Numbers and Flow

    Directory of Open Access Journals (Sweden)

    Yanfeng Wang

    2015-01-01

    Full Text Available Hub and spoke network problem is solved as part of a strategic decision making process which may have a profound effect on the future of enterprises. In view of the existing network structure, as time goes on, the number of spokes and the flow change because of different sources of uncertainty. Hence, the incremental optimization of hub and spoke network problem is considered in this paper, and the policy makers should adopt a series of strategies to cope with the change, such as setting up new hubs, adjusting the capacity level of original hubs, or closing some original hubs. The objective is to minimize the total cost, which includes the setup costs for the new hubs, the closure costs, and the adjustment costs for the original hubs as well as the flow routing costs. Two mixed-integer linear programming formulations are proposed and analyzed for this problem. China Deppon Logistics as an example is performed to present computational analysis, and we analyze the changes in the solutions driven by the number of spokes and the flow. The tests also allow an analysis to consider the effect of variation in parameters on network.

  9. Fatigue based design and analysis of wheel hub for Student formula car by Simulation Approach

    Science.gov (United States)

    Gowtham, V.; Ranganathan, A. S.; Satish, S.; Alexis, S. John; Siva kumar, S.

    2016-09-01

    In the existing design of Wheel hub used for Student formula cars, the brake discs cannot be removed easily since the disc is mounted in between the knuckle and hub. In case of bend or any other damage to the disc, the replacement of the disc becomes difficult. Further using OEM hub and knuckle that are used for commercial vehicles will result in increase of unsprung mass, which should be avoided in Student formula cars for improving the performance. In this design the above mentioned difficulties have been overcome by redesigning the hub in such a way that the brake disc could be removed easily by just removing the wheel and the caliper and also it will have reduced weight when compared to existing OEM hub. A CAD Model was developed based on the required fatigue life cycles. The forces acting on the hub were calculated and linear static structural analysis was performed on the wheel hub for three different materials using ANSYS Finite Element code V 16.2. The theoretical fatigue strength was compared with the stress obtained from the structural analysis for each material.

  10. A multidomain hub anchors the chromosome segregation and chemotactic machinery to the bacterial pole.

    Science.gov (United States)

    Yamaichi, Yoshiharu; Bruckner, Raphael; Ringgaard, Simon; Möll, Andrea; Cameron, D Ewen; Briegel, Ariane; Jensen, Grant J; Davis, Brigid M; Waldor, Matthew K

    2012-10-15

    The cell poles constitute key subcellular domains that are often critical for motility, chemotaxis, and chromosome segregation in rod-shaped bacteria. However, in nearly all rods, the processes that underlie the formation, recognition, and perpetuation of the polar domains are largely unknown. Here, in Vibrio cholerae, we identified HubP (hub of the pole), a polar transmembrane protein conserved in all vibrios, that anchors three ParA-like ATPases to the cell poles and, through them, controls polar localization of the chromosome origin, the chemotactic machinery, and the flagellum. In the absence of HubP, oriCI is not targeted to the cell poles, chemotaxis is impaired, and a small but increased fraction of cells produces multiple, rather than single, flagella. Distinct cytoplasmic domains within HubP are required for polar targeting of the three ATPases, while a periplasmic portion of HubP is required for its localization. HubP partially relocalizes from the poles to the mid-cell prior to cell division, thereby enabling perpetuation of the polar domain in future daughter cells. Thus, a single polar hub is instrumental for establishing polar identity and organization.

  11. Hubs and authorities in the world trade network using a weighted HITS algorithm.

    Science.gov (United States)

    Deguchi, Tsuyoshi; Takahashi, Katsuhide; Takayasu, Hideki; Takayasu, Misako

    2014-01-01

    We investigate the economic hubs and authorities of the world trade network (WTN) from 1992 to 2012, an era of rapid economic globalization. Using a well-defined weighted hyperlink-induced topic search (HITS) algorithm, we can calculate the values of the weighted HITS hub and authority for each country in a conjugate way. In the context of the WTN, authority values are large for countries with significant imports from large hub countries, and hub values are large for countries with significant exports to high-authority countries. The United States was the largest economic authority in the WTN from 1992 to 2012. The authority value of the United States has declined since 2001, and China has now become the largest hub in the WTN. At the same time, China's authority value has grown as China is transforming itself from the "factory of the world" to the "market of the world." European countries show a tendency to trade mostly within the European Union, which has decreased Europe's hub and authority values. Japan's authority value has increased slowly, while its hub value has declined. These changes are consistent with Japan's transition from being an export-driven economy in its high economic growth era in the latter half of the twentieth century to being a more mature, economically balanced nation.

  12. Hubs and authorities in the world trade network using a weighted HITS algorithm.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Deguchi

    Full Text Available We investigate the economic hubs and authorities of the world trade network (WTN from 1992 to 2012, an era of rapid economic globalization. Using a well-defined weighted hyperlink-induced topic search (HITS algorithm, we can calculate the values of the weighted HITS hub and authority for each country in a conjugate way. In the context of the WTN, authority values are large for countries with significant imports from large hub countries, and hub values are large for countries with significant exports to high-authority countries. The United States was the largest economic authority in the WTN from 1992 to 2012. The authority value of the United States has declined since 2001, and China has now become the largest hub in the WTN. At the same time, China's authority value has grown as China is transforming itself from the "factory of the world" to the "market of the world." European countries show a tendency to trade mostly within the European Union, which has decreased Europe's hub and authority values. Japan's authority value has increased slowly, while its hub value has declined. These changes are consistent with Japan's transition from being an export-driven economy in its high economic growth era in the latter half of the twentieth century to being a more mature, economically balanced nation.

  13. Tank 241-AY-102 Secondary Liner Corrosion Evaluation - 14191

    Energy Technology Data Exchange (ETDEWEB)

    Boomer, Kayle D. [Washington River Protection Solutions (United States); Washenfelder, Dennis J. [Washington River Protection Solutions (United States); Johnson, Jeremy M. [Department of Energy, Washington, DC (United States). Office of River Protection

    2014-01-07

    In October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of 241-AY-102 (AY-102) was leaking. A number of evaluations were performed after discovery of the leak which identified corrosion from storage of waste at the high waste temperatures as one of the major contributing factors in the failure of the tank. The propensity for corrosion of the waste on the annulus floor will be investigated to determine if it is corrosive and must be promptly removed or if it is benign and may remain in the annulus. The chemical composition of waste, the temperature and the character of the steel are important factors in assessing the propensity for corrosion. Unfortunately, the temperatures of the wastes in contact with the secondary steel liner are not known; they are estimated to range from 45 deg C to 60 deg C. It is also notable that most corrosion tests have been carried out with un-welded, stress-relieved steels, but the secondary liner in tank AY-102 was not stress-relieved. In addition, the cold weather fabrication and welding led to many problems, which required repeated softening of the metal to flatten secondary bottom during its construction. This flame treatment may have altered the microstructure of the steel.

  14. Plasma Guns for the Plasma Liner Experiment (PLX)

    Science.gov (United States)

    Witherspoon, F. D.; Bomgardner, R.; Case, A.; Messer, S. J.; Brockington, S.; Wu, L.; Elton, R.; Hsu, S. C.; Cassibry, J. T.; Gilmore, M. A.

    2009-11-01

    A spherical array of minirailgun plasma accelerators is planned for the Plasma Liner Experiment (PLX) to be located at LANL. The plasma liner would be formed via merging of 30 dense, high Mach number plasma jets (n˜10^16-17 cm-3, M˜10--35, v˜50--70 km/s, rjet˜5 cm) in a spherically convergent geometry. Small parallel-plate railguns are being developed for this purpose due to their reduced system complexity and cost, with each gun planned to operate at ˜300 kA peak current, and launching up to ˜8000 μg of high-Z plasma using a ˜50 kJ pfn. We describe experimental development of the minirailguns and their current and projected performance. Fast operating repetitive gas valves have recently been added to allow injection of high density gases including helium, argon, and (eventually) xenon. We will present the latest test results with the high-Z gases, and discuss future plans for augmenting the rails, optimizing the nozzle configuration, preionizing the injected gas, and configuring the pulse forming networks with the capacitors available to the program.

  15. Formation of imploding plasma liners for fundamental HEDP studies and MIF Standoff Driver Concept

    Energy Technology Data Exchange (ETDEWEB)

    Cassibry, Jason [Univ. of AL in Huntsville; Hatcher, Richard [Univ. of AL in Huntsville; Stanic, Milos [Univ. of AL in Huntsville

    2013-08-17

    The disciplines of High Energy Density Physics (HEDP) and Inertial Confinement Fusion (ICF) are characterized by hypervelocity implosions and strong shocks. The Plasma Liner Experiment (PLX) is focused on reaching HEDP and/or ICF relevant regimes in excess of 1 Mbar peak pressure by the merging and implosion of discrete plasma jets, as a potentially efficient path towards these extreme conditions in a laboratory. In this work we have presented the first 3D simulations of plasma liner, formation, and implosion by the merging of discrete plasma jets in which ionization, thermal conduction, and radiation are all included in the physics model. The study was conducted by utilizing a smoothed particle hydrodynamics code (SPHC) and was a part of the plasma liner experiment (PLX). The salient physics processes of liner formation and implosion are studied, namely vacuum propagation of plasma jets, merging of the jets (liner forming), implosion (liner collapsing), stagnation (peak pressure), and expansion (rarefaction wave disassembling the target). Radiative transport was found to significantly reduce the temperature of the liner during implosion, thus reducing the thermal leaving more pronounced gradients in the plasma liner during the implosion compared with ideal hydrodynamic simulations. These pronounced gradients lead to a greater sensitivity of initial jet geometry and symmetry on peak pressures obtained. Accounting for ionization and transport, many cases gave higher peak pressures than the ideal hydrodynamic simulations. Scaling laws were developed accordingly, creating a non-dimensional parameter space in which performance of an imploding plasma jet liner can be estimated. It is shown that HEDP regimes could be reached with ~ 5 MJ of liner energy, which would translate to roughly 10 to 20 MJ of stored (capacitor) energy. This is a potentially significant improvement over the currently available means via ICF of achieving HEDP and nuclear fusion relevant parameters.

  16. Study on Economic Regulation of Collaborative Strategies among Container Shipping Companies Following Repeal of European Union Regulation 4056/86

    Directory of Open Access Journals (Sweden)

    Rawindaran Nair

    2016-06-01

    Full Text Available The European Union removed the block exemption granted under Regulation 4056/86, to liner shipping companies to provide scheduled services on a collaborative basis effective October 2008. This has also been followed by the proposed P3 alliance with participation of Maersk, MSC and CMA CGM. This paper explores, the arguments adopted by the US Federal Maritime Commission, the European Commission and the Ministry of Commerce of China, in rejecting the case proposed by the P3 alliance. The findings of this paper will inform on understanding strategies adopted by major Competition Regulatory authorities in their interpretation of horizontal collaboration in the industry.

  17. 合成气中枢%Syngas Hub

    Institute of Scientific and Technical Information of China (English)

    徐恒泳; 葛庆杰; 李文钊

    2011-01-01

    回顾了人类使用化石能源所经历的煤(固体)、石油(液体)和天然气(气体)燃料的3个时期.针对近年来环境安全和能源清洁化日益重要,而化石能源仍占世界能源主要消费结构的现状,提出了“合成气中枢”的新概念.重点介绍了从天然气、煤和生物质等多种原料气化生产合成气并进行组成调变;煤基和天然气基合成气制化学品的差别;合成气的转化利用,特别是在发电和热-电-化学品多联产、制取清洁燃料和烯烃以及制取代用天然气等方面的研究进展并进行了评述.认为合成气中枢将成为连接石油炼制、石油化工、天然气化工和煤化工以及电力行业的桥梁,有利于资源和能量的最佳利用以及CO2减排.%The consumption history of fossil energy sources including coal ( solid), petroleum (liquid) and natural gas (gas) was briefly reviewed. Although the seeking for non-fossil energy sources is becoming urgent due to the more and more serious global warming, the fossil energy sources will still occupy more than 50% of the global energy consumption before 2050. Therefore, the concept of syngas hub was brought forward, and the following aspects were emphasized in this review: syngas production and its composition adjustment, the difference of syngas to chemicals from coal and natural gas, and syngas conversion and utilization. It was thought that the syngas hub will become a bridge which connects petroleum refining, petrochemical industry, natural gas chemical industry, coal chemical industry and electric power industry, and is further beneficial to the low CO2 emission and the optimal utilization of resources and energy sources.

  18. On the Popularity of GitHub Applications: A Preliminary Note

    OpenAIRE

    Borges, Hudson; Valente, Marco Tulio; Hora, Andre; Coelho, Jailton

    2015-01-01

    GitHub is the world's largest collection of open source software. Therefore, it is important both to software developers and users to compare and track the popularity of GitHub repositories. In this paper, we propose a framework to assess the popularity of GitHub software, using their number of stars. We also propose a set of popularity growth patterns, which describe the evolution of the number of stars of a system over time. We show that stars tend to correlate with other measures, like for...

  19. Inductively Driven, 3D Liner Compression of a Magnetized Plasma to Megabar Energy Densities

    Energy Technology Data Exchange (ETDEWEB)

    Slough, John [MSNW LLC, Redmond, WA (United States)

    2015-02-01

    To take advantage of the smaller scale, higher density regime of fusion an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. What is proposed is a more flexible metallic liner compression scheme that minimizes the kinetic energy required to reach fusion. It is believed that it is possible to accomplish this at sub-megajoule energies. This however will require operation at very small scale. To have a realistic hope of inexpensive, repetitive operation, it is essential to have the liner kinetic energy under a megajoule which allows for the survivability of the vacuum and power systems. At small scale the implosion speed must be reasonably fast to maintain the magnetized plasma (FRC) equilibrium during compression. For limited liner kinetic energy, it becomes clear that the thinnest liner imploded to the smallest radius consistent with the requirements for FRC equilibrium lifetime is desired. The proposed work is directed toward accomplishing this goal. Typically an axial (Z) current is employed for liner compression. There are however several advantages to using a θ-pinch coil. With the θ-pinch the liner currents are inductively driven which greatly simplifies the apparatus and vacuum system, and avoids difficulties with the post implosion vacuum integrity. With fractional flux leakage, the foil liner automatically provides for the seed axial compression field. To achieve it with optimal switching techniques, and at an accelerated pace however will require additional funding. This extra expense is well justified as the compression technique that will be enabled by this funding is unique in the ability to implode individual segments of the liner at different times. This is highly advantageous as the liner can be imploded in a manner that maximizes the energy transfer to the FRC. Production of shaped liner implosions for additional axial compression can thus be readily accomplished with the modified power

  20. Quantification of prosthetic outcomes: elastomeric gel liner with locking pin suspension versus polyethylene foam liner with neoprene sleeve suspension.

    Science.gov (United States)

    Coleman, Kim L; Boone, David A; Laing, Linda S; Mathews, David E; Smith, Douglas G

    2004-07-01

    For this randomized crossover trial, we compared two common transtibial socket suspension systems: the Alpha liner with distal locking pin and the Pe-Lite liner with neoprene suspension sleeve. Our original hypotheses asserted that increased ambulatory activity, wear time, comfort, and satisfaction would be found with the elastomeric suspension system. Thirteen subjects completed the study. Following 2.5-month accommodation to each condition, ambulatory activity was recorded (steps/minute for 2 weeks), and subjects completed three questionnaires specific to prosthesis use and pain: the Prosthesis Evaluation Questionnaire (PEQ), a Brief Pain Inventory (BPI) excerpt, and the Socket Comfort Score (SCS). Upon completion, subjects selected their favored system for continued use. Ten subjects preferred the Pe-Lite and three the Alpha. Subjects spent 82% more time wearing the Pe-Lite and took 83% more steps per day. Ambulatory intensity distribution did not differ between systems. No statistically significant differences were found in questionnaire results. Subject feedback for each system was both positive and negative.