The Concept of Basic Income: Global Experience and Implementation Possibilities in Lithuania

Directory of Open Access Journals (Sweden)

Algimantas Laurinavičius

2016-06-01

Full Text Available The article gives an overview of universal basic income as one of the instruments of the asset-based policy, analyses its theoretical concept and practical examples. Latest trends in Europe, especially in Finland and Switzerland, are overviewed and possibilities to implement such an instrument in Lithuania are evaluated. Research methods of scientific literature analysis, comparative and logical analysis of statistical data, data grouping and presentation were used. Article finds out that the concept of basic income is being implemented on a small scale in the US state of Alaska and in a small autonomous territory of China – Macao. Finland and Switzerland are determined to fully implement the concept of basic income by providing monthly benefits to all their citizens. Although Lithuania is categorized as a country with high income inequality and high level of poverty risk, currently it is not possible to implement the concept of basic income in Lithuania: the state social insurance fund budget would not be able to fund sufficient benefits, and the benefits that could be provided by the budget would not comply with the objectives of the concept of basic income.

The availability and accessibility of basic concept vocabulary in AAC software: a preliminary study.

Science.gov (United States)

McCarthy, Jillian H; Schwarz, Ilsa; Ashworth, Morgan

2017-09-01

Core vocabulary lists obtained through the analyses of children's utterances include a variety of basic concept words. Supporting young children who use augmentative and alternative communication (AAC) to develop their understanding and use of basic concepts is an area of practice that has important ramifications for successful communication in a classroom environment. This study examined the availability of basic concept words across eight frequently used, commercially available AAC language systems, iPad© applications, and symbol libraries used to create communication boards. The accessibility of basic concept words was subsequently examined using two AAC language page sets and two iPad applications. Results reveal that the availability of basic concept words represented within the different AAC language programs, iPad applications, and symbol libraries varied but was limited across programs. However, there is no significant difference in the accessibility of basic concept words across the language program page sets or iPad applications, generally because all of them require sophisticated motor and cognitive plans for access. These results suggest that educators who teach or program vocabulary in AAC systems need to be mindful of the importance of basic concept words in classroom settings and, when possible, enhance the availability and accessibility of these words to users of AAC.

Introduction to basic concepts and elements in process synthesis and process intensification

DEFF Research Database (Denmark)

Rong, Ben-Guang

2017-01-01

In this chapter, we introduce some basic concepts and elements for process synthesis (PS) and process intensification (PI). These basic concepts and elements are taken partially from distillation systems synthesis and intensification, as described in Chapter 2. In Chapter 2,we present six distill...... these common concepts and elements in the context of general PS and PI works. We hope that at least some of the concepts and elements can be examined and addressed in the methodological approaches for PS and PI....

Basic concepts of materials accounting

International Nuclear Information System (INIS)

Markin, J.T.

1989-01-01

The importance of accounting for nuclear materials to the efficient, safe, and economical operation of nuclear facilities is introduced, and the following topics are covered: material balance equation; item control areas; material balance uncertainty; decision procedures for materials accounting; conventional and near-real-time accounting; regulatory requirements of the US Department of Energy and the Nuclear Regulatory Commission; and a summary related to the development of a materials accounting system to implement the basic concepts described. The summary includes a section on each of the following: problem definition, system objectives, and system design

Self-Concept and Sport Participation in Sixth Grade Basic School Students

Directory of Open Access Journals (Sweden)

Špela Virag

2016-04-01

Full Text Available The purpose of the study was to examine self-concept in relation to sport participation among basic school children. The sample included 109 sixth grade students of different Slovenian basic schools. The participants completed the Slovenian version of the SelfPerception Profile for Children – SPPC. The results show significant gender differences in some specific components of self-concept. Boys exhibited higher scores in perceived physical appearance and athletic competence, whereas girls exhibited higher levels in perceived behavioural conduct. Mean values show that students, engaged in organized sport practice, reported higher scores in all self-concept subscales than their inactive peers, although significant differences between these two groups were found in perceived scholastic competence and athletic competence. The study offers a detailed insight into the multidimensional self-perceptions of sixth grade basic school students. The results highlight the importance of physical/sports activity in the self-concept development and can be useful in promoting an active lifestyle among youth.

Effects of turbulence on mixed-phase deep convective clouds under different basic-state winds and aerosol concentrations

Science.gov (United States)

Lee, Hyunho; Baik, Jong-Jin; Han, Ji-Young

2014-12-01

The effects of turbulence-induced collision enhancement (TICE) on mixed-phase deep convective clouds are numerically investigated using a 2-D cloud model with bin microphysics for uniform and sheared basic-state wind profiles and different aerosol concentrations. Graupel particles account for the most of the cloud mass in all simulation cases. In the uniform basic-state wind cases, graupel particles with moderate sizes account for some of the total graupel mass in the cases with TICE, whereas graupel particles with large sizes account for almost all the total graupel mass in the cases without TICE. This is because the growth of ice crystals into small graupel particles is enhanced due to TICE. The changes in the size distributions of graupel particles due to TICE result in a decrease in the mass-averaged mean terminal velocity of graupel particles. Therefore, the downward flux of graupel mass, and thus the melting of graupel particles, is reduced due to TICE, leading to a decrease in the amount of surface precipitation. Moreover, under the low aerosol concentration, TICE increases the sublimation of ice particles, consequently playing a partial role in reducing the amount of surface precipitation. The effects of TICE are less pronounced in the sheared basic-state wind cases than in the uniform basic-state wind cases because the number of ice crystals is much smaller in the sheared basic-state wind cases than in the uniform basic-state wind cases. Thus, the size distributions of graupel particles in the cases with and without TICE show little difference.

Topics in current aerosol research

CERN Document Server

Hidy, G M

1971-01-01

Topics in Current Aerosol Research deals with the fundamental aspects of aerosol science, with emphasis on experiment and theory describing highly dispersed aerosols (HDAs) as well as the dynamics of charged suspensions. Topics covered range from the basic properties of HDAs to their formation and methods of generation; sources of electric charges; interactions between fluid and aerosol particles; and one-dimensional motion of charged cloud of particles. This volume is comprised of 13 chapters and begins with an introduction to the basic properties of HDAs, followed by a discussion on the form

Basic Concepts of Reading Instruction

Directory of Open Access Journals (Sweden)

Gökhan ARI

2017-12-01

Full Text Available Reading act is performed by connected physiological, psychological and cognitive processes. The operations taking place in these processes are expected to continue for life by being developed with certain strategies. A lot of information is gained with reading skill in education life. Therefore, basic concepts that constitute reading education in teaching and improving reading are important for teachers. The aim of this study is to submit information compiled from the literature about reading education process and which basic concepts are used in reading education. While teaching reading from part to whole, from whole to part and interactional approaches are used. From part to whole approach is at the forefront. Then with interactional approach strategies, both code solving and making sense is improved. Teachers should know the characteristics of bouncing, stopping, turning back, and scanning movements of the eye both in code solving and making sense. The teacher should configure the teaching for the students to gain fluid reading elements by making use of reading out and reading silently. After reading act is acquired; good reader characteristics should be gained by improving asking questions, guessing, summarizing, interpretation skills in integrated readings. Reading skill is improved by studies on the text. Therefore, the students should come across texts that are suitable to their levels, textuality and readability criteria. The vocabulary of children should be improved in a planned way with text-based word and meaning studies. Fluid reading, making sense and interpretation skills of children should be pursued with different evaluation types. In the long term, work should be done to make reading a habit for them.

Identifying Students' Conceptions of Basic Principles in Sequence Stratigraphy

Science.gov (United States)

Herrera, Juan S.; Riggs, Eric M.

2013-01-01

Sequence stratigraphy is a major research subject in the geosciences academia and the oil industry. However, the geoscience education literature addressing students' understanding of the basic concepts of sequence stratigraphy is relatively thin, and the topic has not been well explored. We conducted an assessment of 27 students' conceptions of…

Basic units and concepts in radiation exposures

International Nuclear Information System (INIS)

Mlekodaj, R.L.

1992-01-01

Some of the most common units, concepts and models in use today in dealing with radiation exposures and the associated risks are presented. Discussions toward a better understanding of some of the basic difficulties in quantifying risks associated with low levels of radiation are presented. The main thrust of this talk is to lay a foundation for better understanding and appreciation of the talks to follow in this symposium

Plasma basic concepts and nitrogen containing plasmas

OpenAIRE

Sanz Lluch, M. del Mar; Tanarro, Isabel

2007-01-01

Basic concepts related to plasmas are described as well as the typical characterization methods currently available. A brief overview about some plasma applications is given, but focusing on plasma used in material processing mainly devoted to the microelectronics industry. Finally, specific applications related to plasma-assisted MBE for nitrides and dilute nitrides are given, showing some interesting research works performed to that purpose, and giving the usual characterization techniques ...

Basic concepts from magnetic resonance imaging

International Nuclear Information System (INIS)

Rodriguez Arroyo, Diego

2011-01-01

The use of magnetic resonance imaging (MRI) has grown exponentially, due in part to excellent anatomic and pathologic detail provided by the modality, as recent technological advances that have led to more rapid acquisition times. Radiology residents in different parts of the world now receive training in MR images from their first year of residence, included the pulse sequences training spin-echo, gradient-echo, inversion-recovery, echo-planar image and MR angiographic sequences, commonly used in medical imaging. However, to optimize the use of this type of study, it has been necessary to understand the basic concepts of physics, included the concepts of recovery T1, degradation T2* and T2, repetition time, echo time, and the effects of chemical shift. Additionally, it has been important to understand the contrast weighting for better representation of specific tissues and thus perform an appropriate differential diagnosis of various pathological processes. (author) [es

Development of FBR integrity system code. Basic concept

International Nuclear Information System (INIS)

Asayama, Tai

2001-05-01

For fast breeder reactors to be commercialized, they must be more reliable, safer, and at the same, economically competitive with future light water reactors. Innovation of elevated temperature structural design standard is necessary to achieve this goal. The most powerful way is to enlarge the scope of structural integrity code to cover items other than design evaluation that has been addressed in existing codes. Items that must be newly covered are prerequisites of design, fabrication, examination, operation and maintenance, etc. This allows designers to choose the most economical combination of design variations to achieve specific reliability that is needed for a particular component. Designing components by this concept, a cost-minimum design of a whole plant can be realized. By determining the reliability that must be achieved for a component by risk technologies, further economical improvement can be expected by avoiding excessive quality. Recognizing the necessity for the codes based on the new concept, the development of 'FBR integrity system code' began in 2000. Research and development will last 10 years. For this development, the basic logistics and system as well as technologies that materialize the concept are necessary. Original logistics and system must be developed, because no existing researches are available in and out of Japan. This reports presents the results of the work done in the first year regarding the basic idea, methodology, and structure of the code. (author)

The basic concept for the geological surveys

International Nuclear Information System (INIS)

Deguchi, Akira; Takahashi, Yoshiaki

1998-01-01

Before the construction of high level radioactive waste repository, the implementing entity will go through three siting stages for the repository. In each of those three stages, the implementing entity will carry out geological surveys. In this report, the concept for the geological surveys is described, on the basic of 'The policies for the high level radioactive waste disposal (a tentative draft)' issued by the Atomic Energy Commission in July, 1997. (author)

Students' Self-Concept and Their Achievement in Basic Science ...

African Journals Online (AJOL)

The study investigated the relationship between students self-concept andtheir academic performance in Basic Science. It further examines genderdifference in students performance. The study adopted ex-post factorresearch design and made use of 300 students all from Public Schools. Theadapted Version of ...

Basic concepts and assumptions behind the new ICRP recommendations

International Nuclear Information System (INIS)

Lindell, B.

1979-01-01

A review is given of some of the basic concepts and assumptions behind the current recommendations by the International Commission on Radiological Protection in ICRP Publications 26 and 28, which form the basis for the revision of the Basic Safety Standards jointly undertaken by IAEA, ILO, NEA and WHO. Special attention is given to the assumption of a linear, non-threshold dose-response relationship for stochastic radiation effects such as cancer and hereditary harm. The three basic principles of protection are discussed: justification of practice, optimization of protection and individual risk limitation. In the new ICRP recommendations particular emphasis is given to the principle of keeping all radiation doses as low as is reasonably achievable. A consequence of this is that the ICRP dose limits are now given as boundary conditions for the justification and optimization procedures rather than as values that should be used for purposes of planning and design. The fractional increase in total risk at various ages after continuous exposure near the dose limits is given as an illustration. The need for taking other sources, present and future, into account when applying the dose limits leads to the use of the commitment concept. This is briefly discussed as well as the new quantity, the effective dose equivalent, introduced by ICRP. (author)

Basic conceptions for reactor pressure vessel manipulators and their evaluation

International Nuclear Information System (INIS)

Popp, P.

1987-01-01

The study deals with application fields and basic design conceptions of manipulators in reactor pressure vessels as well as their evaluation. It is shown that manipulators supported at the reactor flange have essential advantages

Fundamentals in Biostatistics for Research in Pediatric Dentistry: Part I - Basic Concepts.

Science.gov (United States)

Garrocho-Rangel, J A; Ruiz-Rodríguez, M S; Pozos-Guillén, A J

The purpose of this report was to provide the reader with some basic concepts in order to better understand the significance and reliability of the results of any article on Pediatric Dentistry. Currently, Pediatric Dentists need the best evidence available in the literature on which to base their diagnoses and treatment decisions for the children's oral care. Basic understanding of Biostatistics plays an important role during the entire Evidence-Based Dentistry (EBD) process. This report describes Biostatistics fundamentals in order to introduce the basic concepts used in statistics, such as summary measures, estimation, hypothesis testing, effect size, level of significance, p value, confidence intervals, etc., which are available to Pediatric Dentists interested in reading or designing original clinical or epidemiological studies.

Unders and Overs: Using a Dice Game to Illustrate Basic Probability Concepts

Science.gov (United States)

McPherson, Sandra Hanson

2015-01-01

In this paper, the dice game "Unders and Overs" is described and presented as an active learning exercise to introduce basic probability concepts. The implementation of the exercise is outlined and the resulting presentation of various probability concepts are described.

Bridging the Gap Between Science and Clinical Efficacy: Physiology, Imaging, and Modeling of Aerosols in the Lung.

Science.gov (United States)

Darquenne, Chantal; Fleming, John S; Katz, Ira; Martin, Andrew R; Schroeter, Jeffry; Usmani, Omar S; Venegas, Jose; Schmid, Otmar

2016-04-01

Development of a new drug for the treatment of lung disease is a complex and time consuming process involving numerous disciplines of basic and applied sciences. During the 2015 Congress of the International Society for Aerosols in Medicine, a group of experts including aerosol scientists, physiologists, modelers, imagers, and clinicians participated in a workshop aiming at bridging the gap between basic research and clinical efficacy of inhaled drugs. This publication summarizes the current consensus on the topic. It begins with a short description of basic concepts of aerosol transport and a discussion on targeting strategies of inhaled aerosols to the lungs. It is followed by a description of both computational and biological lung models, and the use of imaging techniques to determine aerosol deposition distribution (ADD) in the lung. Finally, the importance of ADD to clinical efficacy is discussed. Several gaps were identified between basic science and clinical efficacy. One gap between scientific research aimed at predicting, controlling, and measuring ADD and the clinical use of inhaled aerosols is the considerable challenge of obtaining, in a single study, accurate information describing the optimal lung regions to be targeted, the effectiveness of targeting determined from ADD, and some measure of the drug's effectiveness. Other identified gaps were the language and methodology barriers that exist among disciplines, along with the significant regulatory hurdles that need to be overcome for novel drugs and/or therapies to reach the marketplace and benefit the patient. Despite these gaps, much progress has been made in recent years to improve clinical efficacy of inhaled drugs. Also, the recent efforts by many funding agencies and industry to support multidisciplinary networks including basic science researchers, R&D scientists, and clinicians will go a long way to further reduce the gap between science and clinical efficacy.

Pre-Service Teachers' Mental Models of Basic Astronomy Concepts

Science.gov (United States)

Arslan, A. Saglam; Durikan, U.

2016-01-01

The aim of the present study is to determine pre-service teachers' mental models related to basic astronomy concepts. The study was conducted using a survey method with 293 pre-service teachers from 4 different departments; physics education, science education, primary teacher education and early childhood education. An achievement test with…

Three Short Films about Water: Presenting Basic Concepts to Students and Stakeholders

Science.gov (United States)

Arrigo, J. S.; Hooper, R. P.; Michel, A.; Wilde, P.; Lilienfeld, L.

2011-12-01

Three short form (3 - 5 minute) movies were produced for CUAHSI, to convey basic concepts such as a hydrologic budget, stores and fluxes of water, and the flowpaths and residence time of water. The films were originally intended to be used by scientists to explain the concepts behind potential environmental observatories, but evolved into serving a broader purpose. The films combine still photos, satellite images, animation and video clips, and interviews with CUAHSI members explaining hydrologic concepts in simple, accessible terms. In producing these films, we have found the importance of engaging scientists in conversation first, to develop a script around key accessible concepts and relevant information. Film and communication professionals play a critical role in distilling the scientific explanation and concepts into accessible, engaging film material. The films have been widely distributed through CD and online to educators for use in courses. Additionally, they provide a way to engage stakeholders, particularly land owners, by conveying basic concepts that are necessary to understand the hydrologic and earth science foundation of many of today's political and environmental issues. The films can be viewed online at the CUAHSI website, which also contains links to other film related resources and programs.

Modelling aerosol behavior in reactor cooling systems

International Nuclear Information System (INIS)

McDonald, B.H.

1990-01-01

This paper presents an overview of some of the areas of concern in using computer codes to model fission-product aerosol behavior in the reactor cooling system (RCS) of a water-cooled nuclear reactor during a loss-of-coolant accident. The basic physical processes that require modelling include: fission product release and aerosol formation in the reactor core, aerosol transport and deposition in the reactor core and throughout the rest of the RCS, and the interaction between aerosol transport processes and the thermalhydraulics. In addition to these basic physical processes, chemical reactions can have a large influence on the nature of the aerosol and its behavior in the RCS. The focus is on the physics and the implications of numerical methods used in the computer codes to model aerosol behavior in the RCS

Identifying Students’ Misconceptions on Basic Algorithmic Concepts Through Flowchart Analysis

NARCIS (Netherlands)

Rahimi, E.; Barendsen, E.; Henze, I.; Dagienė, V.; Hellas, A.

2017-01-01

In this paper, a flowchart-based approach to identifying secondary school students’ misconceptions (in a broad sense) on basic algorithm concepts is introduced. This approach uses student-generated flowcharts as the units of analysis and examines them against plan composition and construct-based

Spanish Translation and Validation of the Bracken Basic Concept Scale.

Science.gov (United States)

Bracken, Bruce A; Fouad, Nadya

1987-01-01

The Bracken Basic Concept Scale (BBCS) was translated into Spanish, and 32 preschool and primary age bilingual children were assessed in a counter-balanced format with the English and newly translated Spanish forms to assess the adequacy of the translation. Preliminary content validity of the Spanish BBCS was demonstrated. (Author/JAZ)

Introduction to the Basic-Concepts of Bose-Einstein Condensation

International Nuclear Information System (INIS)

Bagnato, V. S.; Magalhaes, K. M. F.; Seman, J. A.; Henn, E. A. L.; Ramos, E. R. F.

2008-01-01

This text corresponds to part of the course presented at the ELAF XXXVIII. It is composed of work previously done along the years. The level of this introduction follows the last year of undergraduate and first year of graduate courses. We apologize to the experts on this field, but the idea here is to provide the basic principles and tools for students just getting involved with this topic. For those interested in a deeper reading on the subject, we strongly recommend the review article published by Courteille, Bagnato and Yukalov from which part of this text was extracted. The lecture is divided in three parts: an introduction, the basic concepts of Bose-Einstein Condensation and information about making and probing BECs

Examination of the Film "My Father and My Son" According to the Basic Concepts of Multigenerational Family Therapy

Science.gov (United States)

Acar, Tulin; Voltan-Acar, Nilufer

2013-01-01

The aim of this study was to evaluate the basic concepts of multigenerational Family Therapy and to evaluate the scenes of the film ''My Father and My Son'' according to these concepts. For these purposes firstly basic concepts of Multigenerational Family Therapy such as differentiation of self, triangles/triangulation, nuclear family emotional…

Fuzzy logic and neural networks basic concepts & application

CERN Document Server

Alavala, Chennakesava R

2008-01-01

About the Book: The primary purpose of this book is to provide the student with a comprehensive knowledge of basic concepts of fuzzy logic and neural networks. The hybridization of fuzzy logic and neural networks is also included. No previous knowledge of fuzzy logic and neural networks is required. Fuzzy logic and neural networks have been discussed in detail through illustrative examples, methods and generic applications. Extensive and carefully selected references is an invaluable resource for further study of fuzzy logic and neural networks. Each chapter is followed by a question bank

Introduction to Probability, Part 1 - Basic Concepts. Student Text. Revised Edition.

Science.gov (United States)

Blakeslee, David W.; And Others

This book is designed to introduce the reader to some fundamental ideas about probability. The mathematical theory of probability plays an increasingly important role in science, government, industry, business, and economics. An understanding of the basic concepts of probability is essential for the study of statistical methods that are widely…

Basic concepts in the management of heart failure in general clinical ...

African Journals Online (AJOL)

Basic concepts in the management of heart failure in general clinical practice. KO Ogunyankin. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

Endoradiotherapy in cancer treatment--basic concepts and future trends.

Science.gov (United States)

Zoller, Frederic; Eisenhut, Michael; Haberkorn, Uwe; Mier, Walter

2009-12-25

Endoradiotherapy represents an alternative therapeutic method in cancer treatment with advantageous features compared to chemotherapy and radiation therapy. Intelligent dose delivery concepts using small drugs, peptides or antibodies as radionuclide carriers enable the verification of a selective accumulation in the tumour lesion and to reduce radiation toxicity for the peripheral organs. The development of endoradiotherapeutic agents, especially chelator-conjugated biomolecules, for example ibritumomab tiuxetan or DOTATOC, gains importance due to the stable complexation of versatile radiometals, such as (90)Y or (177)Lu. The rational design of novel target binding sides and their grafting into a drug scaffold is a highly promising strategy, which may promote further implication in endoradiotherapy. This review highlights the basic concepts of endoradiotherapy and discusses the potential of targeted therapy and the properties of energy-rich particles emitted by radionuclides for tumour therapy.

The Etymology of Basic Concepts in the Experimental Analysis of Behavior

Science.gov (United States)

Dinsmoor, James A.

2004-01-01

The origins of many of the basic concepts used in the experimental analysis of behavior can be traced to Pavlov's (1927/1960) discussion of unconditional and conditional reflexes in the dog, but often with substantial changes in meaning (e.g., stimulus, response, and reinforcement). Other terms were added by Skinner (1938/1991) to describe his…

Geographies of American Popular Music: Introducing Students to Basic Geographic Concepts

Science.gov (United States)

McClain, Stephen S.

2010-01-01

Popular music can be used to study many subjects and issues related to the social sciences. "Geographies of American Popular Music" was a workshop that not only examined the history and development of select genres of American music, it also introduced students to basic geographic concepts such as the culture hearth and spatial diffusion. Through…

Aerosol typing - key information from aerosol studies

Science.gov (United States)

Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina

2016-04-01

classification. The harmonization of the aerosol typing procedures is a fundamental need in aerosol studies for long-term perspectives, satellite validation, and accuracy. However, the possibilities and limits in defining a common set of aerosol types for satellite missions and ground-based measurements depends on different information content among measurement techniques and for different retrieval conditions (e.g. for low aerosol content there is smaller satellite aerosol type retrieval sensitivity), as well as different historical choices. The concept of aReference database for aerosol typing (REDAT) is developed with the specific purpose of providing a dataset suitable for the comparison of typing procedures (from ground-based, and satellite measurements) and to be used as reference dataset for the modelling community. It will also allow the definition of translating rules between the different aerosol typing nomenclature, information strongly needed for the more and more increased audience of scientific data with no scientific background, as well as policy and decision makers. Acknowledgments: The research leading to these results is partially funded by ACTRIS2 Research Infrastructure Project by the European Union's Horizon 2020 research and innovation programme under the grant agreement n. 654169.

Using a Self-Administered Visual Basic Software Tool To Teach Psychological Concepts.

Science.gov (United States)

Strang, Harold R.; Sullivan, Amie K.; Schoeny, Zahrl G.

2002-01-01

Introduces LearningLinks, a Visual Basic software tool that allows teachers to create individualized learning modules that use constructivist and behavioral learning principles. Describes field testing of undergraduates at the University of Virginia that tested a module designed to improve understanding of the psychological concepts of…

Basic concepts in physics from the cosmos to quarks

CERN Document Server

Chaichian, Masud; Tureanu, Anca

2014-01-01

"Basic Concepts in Physics: From the Cosmos to Quarks" is the outcome of the authors' long and varied teaching experience in different countries and for different audiences, and gives an accessible and eminently readable introduction to all the main ideas of modern physics. The book’s fresh approach, using a novel combination of historical and conceptual viewpoints, makes it ideal complementary reading to more standard textbooks. The first five chapters are devoted to classical physics, from planetary motion to special relativity, always keeping in mind its relevance to questions of contemporary interest. The next six chapters deal mainly with newer developments in physics, from quantum theory and general relativity to grand unified theories, and the book concludes by discussing the role of physics in living systems. A basic grounding in mathematics is required of the reader, but technicalities are avoided as far as possible; thus complex calculations are omitted so long as the essential ideas remain clear....

Aerosol and gamma background measurements at Basic Environmental Observatory Moussala

Directory of Open Access Journals (Sweden)

Angelov Christo

2016-03-01

Full Text Available Trans boundary and local pollution, global climate changes and cosmic rays are the main areas of research performed at the regional Global Atmospheric Watch (GAW station Moussala BEO (2925 m a.s.l., 42°10’45’’ N, 23°35’07’’ E. Real time measurements and observations are performed in the field of atmospheric chemistry and physics. Complex information about the aerosol is obtained by using a threewavelength integrating Nephelometer for measuring the scattering and backscattering coefficients, a continuous light absorption photometer and a scanning mobile particle sizer. The system for measuring radioactivity and heavy metals in aerosols allows us to monitor a large scale radioactive aerosol transport. The measurements of the gamma background and the gamma-rays spectrum in the air near Moussala peak are carried out in real time. The HYSPLIT back trajectory model is used to determine the origin of the data registered. DREAM code calculations [2] are used to forecast the air mass trajectory. The information obtained combined with a full set of corresponding meteorological parameters is transmitted via a high frequency radio telecommunication system to the Internet.

Aerosol core nuclear reactor for space-based high energy/power nuclear-pumped lasers

International Nuclear Information System (INIS)

Prelas, M.A.; Boody, F.P.; Zediker, M.S.

1987-01-01

An aerosol core reactor concept can overcome the efficiency and/or chemical activity problems of other fuel-reactant interface concepts. In the design of a laser using the nuclear energy for a photon-intermediate pumping scheme, several features of the aerosol core reactor concept are attractive. First, the photon-intermediate pumping concept coupled with photon concentration methods and the aerosol fuel can provide the high power densities required to drive high energy/power lasers efficiently (about 25 to 100 kW/cu cm). Secondly, the intermediate photons should have relatively large mean free paths in the aerosol fuel which will allow the concept to scale more favorably. Finally, the aerosol core reactor concept can use materials which should allow the system to operate at high temperatures. An excimer laser pumped by the photons created in the fluorescer driven by a self-critical aerosol core reactor would have reasonable dimensions (finite cylinder of height 245 cm and radius of 245 cm), reasonable laser energy (1 MJ in approximately a 1 millisecond pulse), and reasonable mass (21 kg uranium, 8280 kg moderator, 460 kg fluorescer, 450 kg laser medium, and 3233 kg reflector). 12 references

Initiating Young Children into Basic Astronomical Concepts and Phenomena

Science.gov (United States)

Kallery, M.

2010-07-01

In the present study we developed and implemented three units of activities aiming at acquainting very young children with basic astronomical concepts and phenomena such as the sphericity of the earth, the earth’s movements and the day/night cycle. The activities were developed by a group composed of a researcher/facilitator and six early-years teachers. In the activities children were presented with appropriate for their age scientific information along with conceptual tools such as a globe and an instructional video. Action research processes were used to optimize classroom practices and to gather useful information for the final shaping of the activities and the instruction materials. In these activities the adopted approach to learning can be characterized as socially constructed. The results indicated awareness of concepts and phenomena that the activities dealt with in high percentages of children, storage of the new knowledge in the long term memory and easy retrieval of it, and children’s enthusiasm for the subject.

The Basic Concepts Classification as a Bottom-Up Strategy for the Semantic Web

OpenAIRE

Rick Szostak

2014-01-01

The paper proposes that the Basic Concepts Classification (BCC) could serve as the controlled vocabulary for the Semantic Web. The BCC uses a synthetic approach among classes of things, relators, and properties. These are precisely the sort of concepts required by RDF triples. The BCC also addresses some of the syntactic needs of the Semantic Web. Others could be added to the BCC in a bottom‐up process that carefully evaluates the costs, benefits, and best format for each rule considered.

CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

Science.gov (United States)

Renno, N.; Williams, E.; Rosenfeld, D.; Fischer, D.; Fischer, J.; Kremic, T.; Agrawal, A.; Andreae, M.; Bierbaum, R.; Blakeslee, R.; Boerner, A.; Bowles, N.; Christian, H.; Dunion, J.; Horvath, A.; Huang, X.; Khain, A.; Kinne, S.; Lemos, M.-C.; Penner, J.

2012-04-01

The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. Knowledge of these interactions is foundational to our understanding of weather and climate. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey (NRC 2007) indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) mission concept responds to the IPCC and Decadal Survey concerns by studying the activation of CCN and their interactions with clouds and storms. CHASER proposes to revolutionize our understanding of the interactions of aerosols with clouds by making the first global measurements of the fundamental physical entity linking them: activated cloud condensation nuclei. The CHASER mission was conceptualized to measure all quantities necessary for determining the interactions of aerosols with clouds and storms. Measurements by current satellites allow the determination of crude profiles of cloud particle size but not of the activated CCN that seed them. CHASER uses a new technique (Freud et al. 2011; Rosenfeld et al. 2012) and high-heritage instruments to produce the first global maps of activated CCN and the properties of the clouds associated with them. CHASER measures the CCN concentration and cloud thermodynamic forcing simultaneously, allowing their effects to be distinguished. Changes in the behavior of a group of weather systems in which only one of the quantities varies (a partial derivative of the intensity with the desirable quantity) allow the determination of each effect statistically. The high uncertainties of current climate predictions limit their much-needed use in decision-making. CHASER mitigates this

Review of recent research on the climatic effect of aerosols

International Nuclear Information System (INIS)

Charlock, T.P.; Kondratyev, K.; Prokofyev, M.

1993-01-01

A review of relatively recent research on the climatic effects of aerosols is presented. Most of the inferences of the climatic effects of aerosols have been obtained through assuming a certain aerosol model in conjunction with a particular climate model. The following radiative effects of aerosols are identified: The planetary albedo is generally increased due to the backscatter of solar radiation by aerosols, with the exception of aerosols situated above a highly reflecting surface. Solar radiation absorption by some aerosols can offset the cooling due to aerosol backscatter. Although aerosol effects dominate for short-wave radiation, absorption and emission of terrestrial radiation by aerosols produces a warming effect. Various climate models are used to assess the impact of aerosols on climate. A two-stream approximation to the radiation transfer equation is adequate for optically thin layers where single scattering is applicable. Improved models to include aerosol terrestrial radiation effects, important feedback mechanisms, and the prediction of globally and seasonally averaged surface and atmospheric temperatures are provided by the so-called radiative-convective models (RCM's). The basic structure of the RCM's, which is regarded as adequate for many aerosol climate applications, is described. The general circulation model (GCM) is also described briefly. A full-scale GCM incorporating realistic aerosol inputs is yet to be formulated to include regional variability of the aerosol. Moreover, detailed computer modeling associated with GCM climate models can often confuse the basic physics. Because volcanic aerosols injected into the stratosphere have long residence times, they provide a good case study of the climate response to a change in the atmospheric aerosol. The chapter gives a critique of modeling work done to establish climatic effects of stratospheric aerosols

The Basic Concepts Classification as a Bottom-Up Strategy for the Semantic Web

Directory of Open Access Journals (Sweden)

Rick Szostak

2014-06-01

Full Text Available The paper proposes that the Basic Concepts Classification (BCC could serve as the controlled vocabulary for the Semantic Web. The BCC uses a synthetic approach among classes of things, relators, and properties. These are precisely the sort of concepts required by RDF triples. The BCC also addresses some of the syntactic needs of the Semantic Web. Others could be added to the BCC in a bottom‐up process that carefully evaluates the costs, benefits, and best format for each rule considered.

Stereotactic radiosurgery: basic concepts and current status

International Nuclear Information System (INIS)

Gaur, Maheep Singh

2016-01-01

Term Stereotactic Radiosurgery was coined by Prof Lars Leksell in 1951 as concept. Leksell's experimented together with the radiobiologist Borje Larsson in Uppsala, on trying to develop 'stereotactic radiosurgery', aimed at lesioning in the central brain in functional operations such as thalamotomy and capsulotomy. Clinical experiments using a proton beam were initiated at the Gustav Werner Institute in Uppsala, and a few patients had been treated. Experiences from these led Leksell to design a multi-source 'beam knife', which became ready for use in 1967 as the first 'Gamma Knife' and installed at the private hospital Sophiahammet in Stockholm as a clinical research unit. Moving from functional neurosurgery today Gamma knife is used for a wide range on brain tumors, vascular malformations and functional disorders. Introduction of newer technology in navigation and radiation delivery has made it possible to do whole body Radiosurgery. Various technologies, basic principles, radiobiological aspects and applications will be discussed. (author)

Multinational Validation of the Spanish Bracken Basic Concept Scale for Cross-Cultural Assessments.

Science.gov (United States)

Bracken, Bruce A.; And Others

1990-01-01

Investigated construct validity of the Spanish translation of the Bracken Basic Concept Scale (BBCS) in Latino children (n=293) including monolingual Spanish-speaking children from Puerto Rico and Venezuela and Spanish-dominant bilingual Latino children from Texas. Results provided support for construct validity of the Spanish version of the…

Teaching Future Teachers Basic Astronomy Concepts--Seasonal Changes--at a Time of Reform in Science Education

Science.gov (United States)

Trumper, Ricardo

2006-01-01

Bearing in mind students' misconceptions about basic concepts in astronomy, the present study conducted a series of constructivist activities aimed at changing future elementary and junior high school teachers' conceptions about the cause of seasonal changes, and several characteristics of the Sun-Earth-Moon relative movements like Moon phases,…

Structural Equation Modeling with Mplus Basic Concepts, Applications, and Programming

CERN Document Server

Byrne, Barbara M

2011-01-01

Modeled after Barbara Byrne's other best-selling structural equation modeling (SEM) books, this practical guide reviews the basic concepts and applications of SEM using Mplus Versions 5 & 6. The author reviews SEM applications based on actual data taken from her own research. Using non-mathematical language, it is written for the novice SEM user. With each application chapter, the author "walks" the reader through all steps involved in testing the SEM model including: an explanation of the issues addressed illustrated and annotated testing of the hypothesized and post hoc models expl

Aerosols: generation and role in medicine, industry and environment

International Nuclear Information System (INIS)

Nambi, K.S.V.; Sapra, B.K.

1998-01-01

This book covers a wide range of topics in aerosol sciences. Areas covered for detailed evaluation with respect to the role of aerosols are industry, medicine, health care and environment, besides basic studies. Knowledge in the areas, specially on generation of aerosols and their role in those fields are briefly summarised and problems for future work are highlighted. Articles relevant to INIS are indexed separately

Aerosol exposure: Concepts, criteria, standards and applications

International Nuclear Information System (INIS)

Vincent, James H

2009-01-01

This paper places Inhaled Particles X in the context of the whole sequence of such symposia, going back to the first one in 1961. It draws together some of the essential principles that have been learned since that earlier meeting about the nature of exposure and exposure assessment and thus provides a framework by which to integrate the new knowledge presented at this latest one. In the process, the importance of understanding the formal definition of aerosol exposure is stressed, including the distinction between exposure intensity and exposure history, and how that relates to some measure of cumulative dose which, in turn, may be linked with knowledge about intrinsic toxicity, etc. This then leads to a definition of exposure standards, and the important ingredients of criteria, sampling and limit values. A summary is provided of the current set of particle size-selective criteria that have been widely agreed in the international occupational and environmental health community. Some ideas are presented about how this set might be expanded for certain applications, the important case of ultrafine aerosols being one of them.

Modern concepts for basic radiobiological factors characterizing tumor tissue radiosensitivity

International Nuclear Information System (INIS)

Gocheva, L.; Sergieva, K.

2002-01-01

Traditionally radiotherapy is prescribed at doses consistent with the expected therapeutic response and tolerance of tumor and normal tissues without consideration to individual differences in radiosensitivity. However, the basic radiobiological knowledge and clinical experience along this line point to significant variations in the observed therapeutic results. It has been established that cells and tissues under experimental and clinical conditions manifest a wide spectrum of individual radiosensitivity. The aim of this survey is to outline the current concepts for the basic radiobiological factors influencing tumor radiosensitivity. A thorough discussion is done of the essence, mechanisms of action, methods of determination and measurement, and effect on the prognosis in patients with malignant diseases of a number of radiobiological factors, such as: tumor-cell proliferation, apoptosis, tumor hypoxia and neovascularization. Although the knowledge of the mechanisms of radiosensitivity is constantly expanding, its clinical implementation is still rather limited. The true role of radiosensitivity in predicting the therapeutic response should be more accurately defined. (authors)

The Vital Role of Basic Mathematics in Teaching and Learning the Mole Concept

Science.gov (United States)

Mehrotra, Alka; Koul, Anjni

2016-01-01

This article focuses on the importance of activity-based teaching in understanding the mole concept and the vital role of basic mathematical operations. It describes needs-based training for teachers in a professional development programme in India. Analysis of test results before and after the training indicates that teachers improved their…

Basic concepts in physics. From the cosmos to quarks

International Nuclear Information System (INIS)

Chaichian, M.; Tureanu, A.; Perez Rojas, H.

2014-01-01

A clear, concise and beautifully written presentation of modern physics. Readers will not only learn physics, they will learn to enjoy it. Self-contained and comprehensive History, concepts and formal treatment go hand-in-hand. Suppresses mathematical technicalities in favor of a wide scope of topics. Suited for class use, e.g. as a textbook for the course ''Modern Physics'', but also ideal for ''lone explorers'' and other newcomers to physics. ''Basic Concepts in Physics: From the Cosmos to Quarks'' is the outcome of the authors' long and varied teaching experience in different countries and for different audiences, and gives an accessible and eminently readable introduction to all the main ideas of modern physics. The book's fresh approach, using a novel combination of historical and conceptual viewpoints, makes it ideal complementary reading to more standard textbooks. The first five chapters are devoted to classical physics, from planetary motion to special relativity, always keeping in mind its relevance to questions of contemporary interest. The next six chapters deal mainly with newer developments in physics, from quantum theory and general relativity to grand unified theories, and the book concludes by discussing the role of physics in living systems. A basic grounding in mathematics is required of the reader, but technicalities are avoided as far as possible; thus complex calculations are omitted so long as the essential ideas remain clear. The book is addressed to undergraduate and graduate students in physics and will also be appreciated by many professional physicists. It will likewise be of interest to students, researchers and teachers of other natural sciences, as well as to engineers, high-school teachers and the curious general reader, who will come to understand what physics is about and how it describes the different phenomena of Nature. Not only will readers of this book learn much about physics, they will also learn to love it.

Atomic and molecular spectroscopy basic concepts and applications

CERN Document Server

Kakkar, Rita

2015-01-01

Spectroscopy is the study of electromagnetic radiation and its interaction with solid, liquid, gas and plasma. It is one of the widely used analytical techniques to study the structure of atoms and molecules. The technique is also employed to obtain information about atoms and molecules as a result of their distinctive spectra. The fast-spreading field of spectroscopic applications has made a noteworthy influence on many disciplines, including energy research, chemical processing, environmental protection and medicine. This book aims to introduce students to the topic of spectroscopy. The author has avoided the mathematical aspects of the subject as far as possible; they appear in the text only when inevitable. Including topics such as time-dependent perturbation theory, laser action and applications of Group Theory in interpretation of spectra, the book offers a detailed coverage of the basic concepts and applications of spectroscopy.

Multidimensional Generalized Functions in Aeroacoustics and Fluid Mechanics. Part 1; Basic Concepts and Operations

Science.gov (United States)

Farassat, Fereidoun; Myers, Michael K.

2011-01-01

This paper is the first part of a three part tutorial on multidimensional generalized functions (GFs) and their applications in aeroacoustics and fluid mechanics. The subject is highly fascinating and essential in many areas of science and, in particular, wave propagation problems. In this tutorial, we strive to present rigorously and clearly the basic concepts and the tools that are needed to use GFs in applications effectively and with ease. We give many examples to help the readers in understanding the mathematical ideas presented here. The first part of the tutorial is on the basic concepts of GFs. Here we define GFs, their properties and some common operations on them. We define the important concept of generalized differentiation and then give some interesting elementary and advanced examples on Green's functions and wave propagation problems. Here, the analytic power of GFs in applications is demonstrated with ease and elegance. Part 2 of this tutorial is on the diverse applications of generalized derivatives (GDs). Part 3 is on generalized Fourier transformations and some more advanced topics. One goal of writing this tutorial is to convince readers that, because of their powerful operational properties, GFs are absolutely essential and useful in engineering and physics, particularly in aeroacoustics and fluid mechanics.

Precompound Reactions: Basic Concepts

International Nuclear Information System (INIS)

Weidenmueller, H. A.

2008-01-01

Because of the non-zero nuclear equilibration time, the compound-nucleus scattering model fails when the incident energy exceeds 10 or 20 MeV, and precompound reactions become important. Basic ideas used in the quantum-statistical approaches to these reactions are described

Aerosol science: theory and practice

International Nuclear Information System (INIS)

Williams, M.M.R.; Loyalka, S.K.

1991-01-01

The purpose of this book is twofold. First, it is intended to give a thorough treatment of the fundamentals of aerosol behavior with rigorous proofs and detailed derivations of the basic equations and removal mechanisms. Second, it is intended to provide practical examples with special attention to radioactive particles and their distribution in size following a radioactive release arising from an accident with a nuclear system. We start with a brief introduction to the applications of aerosol science and the characteristics of aerosols in Chapter 1. In Chapter 2, we devote considerable attention to single and two particle motion with respect to both translation and rotation. Chapter 3 contains extensive discussion of the aerosol general dynamical equation and the dependences of aerosol distributions on size, shape, space, composition, radioactivity, and charge. Important particle rate processes of coagulation, condensation, and deposition/resuspension are discussed in the chapters 4, 6 and 7, respectively. In Chapter 5, we provide a thorough treatment of the analytical and numerical methods used in solving the various forms of the aerosol dynamical equation. We discuss the importance and applications of aerosol science to nuclear technology and, in particular, the nuclear source term in Chapter 8. Our focus in this chapter is on discussions of nuclear accidents that can potentially release large amount of radioactivity to environment. We also discuss the progress that has been made in understanding the natural and engineered aerosol processes that limit or affect such releases. (author)

Basic Definitions and Concepts of Systems Approach, Mathematical Modeling and Information Technologies in Sports Science

Directory of Open Access Journals (Sweden)

А. Лопатьєв

2017-09-01

Full Text Available The objective is to systematize and adapt the basic definitions and concepts of the systems approach, mathematical modeling and information technologies to sports science. Materials and methods. The research has studied the availability of appropriate terms in shooting sports, which would meet the requirements of modern sports science. It has examined the compliance of the shooting sports training program for children and youth sports schools, the Olympic reserve specialized children and youth schools, schools of higher sports skills, and sports educational institutions with the modern requirements and principles. Research results. The paper suggests the basic definitions adapted to the requirements of technical sports and sports science. The research has thoroughly analyzed the shooting sports training program for children and youth sports schools, the Olympic reserve specialized children and youth schools, schools of higher sports skills, and sports educational institutions. The paper offers options to improve the training program in accordance with the modern tendencies of training athletes.  Conclusions. The research suggests to systematize and adapt the basic definitions and concepts of the systems approach, mathematical modeling and information technologies using the example of technical sports.

Basic concepts in physics. From the cosmos to quarks

Energy Technology Data Exchange (ETDEWEB)

Chaichian, M.; Tureanu, A. [Helsinki Univ. (Finland). Dept. of Physics; Perez Rojas, H. [ICIMAF, La Habana (Cuba). Dept. of Theoretical Physics

2014-08-01

A clear, concise and beautifully written presentation of modern physics. Readers will not only learn physics, they will learn to enjoy it. Self-contained and comprehensive History, concepts and formal treatment go hand-in-hand. Suppresses mathematical technicalities in favor of a wide scope of topics. Suited for class use, e.g. as a textbook for the course ''Modern Physics'', but also ideal for ''lone explorers'' and other newcomers to physics. ''Basic Concepts in Physics: From the Cosmos to Quarks'' is the outcome of the authors' long and varied teaching experience in different countries and for different audiences, and gives an accessible and eminently readable introduction to all the main ideas of modern physics. The book's fresh approach, using a novel combination of historical and conceptual viewpoints, makes it ideal complementary reading to more standard textbooks. The first five chapters are devoted to classical physics, from planetary motion to special relativity, always keeping in mind its relevance to questions of contemporary interest. The next six chapters deal mainly with newer developments in physics, from quantum theory and general relativity to grand unified theories, and the book concludes by discussing the role of physics in living systems. A basic grounding in mathematics is required of the reader, but technicalities are avoided as far as possible; thus complex calculations are omitted so long as the essential ideas remain clear. The book is addressed to undergraduate and graduate students in physics and will also be appreciated by many professional physicists. It will likewise be of interest to students, researchers and teachers of other natural sciences, as well as to engineers, high-school teachers and the curious general reader, who will come to understand what physics is about and how it describes the different phenomena of Nature. Not only will readers of this book learn

After Almost Half-Century Landing on the Moon and Still Countering Basic Astronomy Conceptions

Science.gov (United States)

Türkmen, Hakan

2015-01-01

The purpose of study is to investigate the fifth graders' understandings of the basic astronomy concept and, if they have, to define their misconceptions and then to determine what reason/s behind them. For this purpose, two hundred seventy fifth grade students from 6 different schools participated. Randomly selected 45 students performing under…

Master Curriculum Guide in Economics. A Framework for Teaching the Basic Concepts. Second Edition.

Science.gov (United States)

Saunders, Phillip; And Others

Intended for curriculum developers, this revised Framework presents a set of basic concepts for teaching K-12 economics. The revision reflects the change and development which the field of economics has undergone and includes improvements suggested by users of the first edition. The purpose of teaching economics is to impart a general…

Basic Concepts in the Taxonomy of Health-Related Behaviors, Habits and Lifestyle

Science.gov (United States)

Salvador-Carulla, Luis; Alonso, Federico; Gomez, Rafael; Walsh, Carolyn O.; Almenara, José; Ruiz, Mencía; Abellán, María José

2013-01-01

Background: Health-related Habits (HrH) are a major priority in healthcare. However there is little agreement on whether exercise, diet, smoking or dental hygiene are better described as lifestyles, habits or behaviors, and on what is their hierarchical relationship. This research is aimed at representing the basic concepts which are assumed to constitute the conceptual framework enabling us to interpret and organize the field of HrH. Methods: A group of 29 experts with different backgrounds agreed on the definition and hierarchy of HrH following an iterative process which involved framing analysis and nominal group techniques. Results: Formal definitions of health-related behavior, habit, life-style and life-style profile were produced. In addition a series of basic descriptors were identified: health reserve, capital, risk and load. Six main categories of HrH were chosen based on relevance to longevity: diet/exercise, vitality/stress, sleep, cognition, substance use and other risk. Attributes of HrH are clinical meaningfulness, quantifiability, temporal stability, associated morbidity, and unitarity (non-redundancy). Two qualifiers (polarity and stages of change) have also been described. Conclusions: The concepts represented here lay the groundwork for the development of clinical and policy tools related to HrH and lifestyle. An adaptation of this system to define targets of health interventions and to develop the classification of person factors in ICF may be needed in the future. PMID:23670578

An Investigation of Mathematical Knowledge Related to Mathematics Teachers' Basic Concepts in Sets Unit

Directory of Open Access Journals (Sweden)

Nurullah YAZICI

2017-05-01

Full Text Available This research was conducted in order to examine the subject matter of Mathematics teachers in the context of "Mathematical Knowledge For Teaching" (MKT model of "Basic Concepts in Sets" which is the first topic of the 9th class "Sets". The study group, which is one of the qualitative research methods, used the case study design, constitutes 5 mathematics teachers who work in different education levels (primary and secondary education in the academic year of 2015-2016. Open-ended questions and semi-structured interview form developed by the researcher were used for data collection. A descriptive analysis technique was used to analyze the data obtained through interviews. While analyzing the data, teacher and student textbooks, which were prepared by the Ministry of National Education for the purpose of teaching in 2015-2016 academic year, were taken as a reference. According to the research findings, it was determined that the teachers had deficiencies in the subject field of "Basic Concepts in the Sets" and had superficial knowledge rather than in depth knowledge.

Lithium vapor/aerosol studies. Interim summary report

International Nuclear Information System (INIS)

Whitlow, G.A.; Bauerle, J.E.; Down, M.G.; Wilson, W.L.

1979-04-01

The temperature/cover gas pressure regime, in which detectable lithium aerosol is formed in a static system has been mapped for argon and helium cover gases using a portable He--Ne laser device. At 538 0 C (1000 0 F), lithium aerosol particles were observed over the range 0.5 to 20 torr and 2 to 10 torr for argon and helium respectively. The experimental conditions in this study were more conducive to aerosol formation than in a fusion reactor. In the real reactor system, very high intensity mechanical and thermal disturbances will be made to the liquid lithium. These disturbances, particularly transient increases in lithium vapor pressure appear to be capable of producing high concentrations of optically-dense aerosol. A more detailed study is, therefore, proposed using the basic information generated in these preliminary experiments, as a starting point. Areas recommended include the kinetics of aerosol formation and the occurrence of supersaturated vapor during rapid vapor pressure transients, and also the effect of lithium agitation (falls, jets, splashing, etc.) on aerosol formation

ECOLOGICAL LIFESTYLE, THE BASIC PRINCIPLES OF THE OPERATIONAL DEFINITION OF THE CONCEPT

Directory of Open Access Journals (Sweden)

Olesya Nikolaevna Tarasova

2015-12-01

Full Text Available Based on the analysis of approaches to the empirical study of the environmental aspects of lifestyle are presented the basic principles that distinguish ecological way of life off the set of environmental practices that need to be taken into account in empirical measurement, namely: systematicity, conceptuality, contextual conformity and processuality. The article provides a theoretical basis and operational definition as an ecological way of life in general and the principles that distinguish it from other concepts of environmental sociology.

Basic concept and its aims of E-journal of advanced maintenance

International Nuclear Information System (INIS)

Miya, Kenzo

2009-01-01

This article describes basic concept and aims of EJAM with history of effort to realize the launching of it. It took about three years until launching of the journal through approach to EPRI and negotiation with international publishing companies. It consists of three major articles. They are 1) general articles, 2) academic papers and 3) maintenance technique to be applied to repairing of components of nuclear power plants. All together of these articles may contribute to understanding of clear image of what maintenance is in this journal. Finally future image of this journal is described in light of maintenance evolution. (author)

Basic Concepts in the Taxonomy of Health-Related Behaviors, Habits and Lifestyle

Directory of Open Access Journals (Sweden)

eVITAL group

2013-05-01

Full Text Available Background: Health-related Habits (HrH are a major priority in healthcare. However there is little agreement on whether exercise, diet, smoking or dental hygiene are better described as lifestyles, habits or behaviors, and on what is their hierarchical relationship. This research is aimed at representing the basic concepts which are assumed to constitute the conceptual framework enabling us to interpret and organize the field of HrH. Methods: A group of 29 experts with different backgrounds agreed on the definition and hierarchy of HrH following an iterative process which involved framing analysis and nominal group techniques. Results: Formal definitions of health-related behavior, habit, life-style and life-style profile were produced. In addition a series of basic descriptors were identified: health reserve, capital, risk and load. Six main categories of HrH were chosen based on relevance to longevity: diet/exercise, vitality/stress, sleep, cognition, substance use and other risk. Attributes of HrH are clinical meaningfulness, quantifiability, temporal stability, associated morbidity, and unitarity (non-redundancy. Two qualifiers (polarity and stages of change have also been described. Conclusions: The concepts represented here lay the groundwork for the development of clinical and policy tools related to HrH and lifestyle. An adaptation of this system to define targets of health interventions and to develop the classification of person factors in ICF may be needed in the future.

Mobile Atmospheric Aerosol and Radiation Characterization Observatory (MAARCO)

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: MAARCO is designed as a stand-alone facility for basic atmospheric research and the collection of data to assist in validating aerosol and weather models....

Teaching Two Basic Nanotechnology Concepts in Secondary School by Using a Variety of Teaching Methods

Science.gov (United States)

Blonder, Ron; Sakhnini, Sohair

2012-01-01

A nanotechnology module was developed for ninth grade students in the context of teaching chemistry. Two basic concepts in nanotechnology were chosen: (1) size and scale and (2) surface-area-to-volume ratio (SA/V). A wide spectrum of instructional methods (e.g., game-based learning, learning with multimedia, learning with models, project based…

APPLICATION OF THE BASIC INCOME CONCEPT IN UKRAINIAN ECONOMY

Directory of Open Access Journals (Sweden)

A. Stavytskyy

2016-01-01

Full Text Available Finance for the social sphere remains a great challenge in modern economy. The necessity of adequate living standards under limited resources raises a complicated problem for governments to provide appropriate distributing mechanism among the most vulnerable sections of the population. The paper analysed the concept of absolute basic income, which in some EU countries is considered as a substitution for a modern system of social security. Inequality of incomes creates not only a social problem but it is also an obstacle in the way of economic growth. It leads to the conclusion that government should provide some strategy to avoid high inequality. The model of rational individual with certain basic income is under investigation. The analysis of the model suggests that the presence of additional income not only facilitates more effective involvement of individuals to work, but it is a sort of indisputable factor for guaranteeing freedom of individuals and increasing their mutual respect. Thus, the idea of basic income, which spreads among European countries, has not only economic, but also political and psychological components that may affect the mentality of people in future. It is demonstrated that the transition to a new social security schemes in Ukraine can accumulate from 856 to 1020 bln. UAH in 2015 prices. It can provide guaranteed monthly payments from 1928 to 2297 UAH per capita and from 482 to 574 USD per child without changing the structure of the budget in case of replacement minimum pensions, minimum wages and full monetization of privileges. Obviously, such strategy not only would improve the efficiency of budget spending, but also produce a multiplier effect on the economy by changing and optimizing the consumption patterns of the population, increasing the competition in all markets for a real consumer. It has a chance of reducing the struggle to obtain state funds through tenders. However, the transition to the new system can be

Recent activities in the Aerosol Generation and Transport Program

International Nuclear Information System (INIS)

Adams, R.E.

1984-01-01

General statements may be made on the behavior of single-component and multi-component aerosols in the Nuclear Safety Pilot Plant vessel. The removal processes for U 3 O 8 , Fe 2 O 3 , and U 3 O 8 + Fe 2 O 3 aerosols are enhanced in a steam-air atmosphere. Steam-air seems to have little effect on removal of concrete aerosol from the vessel atmosphere. A steam-air environment causes a change in aerosol shape from chain-agglomerate to basically spherical for U 3 O 8 , Fe 2 O 3 , and U 3 O 8 + Fe 2 O 3 aerosol; for concrete the change in aerosol shape is from chain-agglomerate to partially spherical. The mass ratio of the individual components of a multi-component aerosol seems to have an observable influence on the resultant behavior of these aerosols in steam. The enhanced rate of removal of the U 3 O 8 , the Fe 2 O 3 , and the mixed U 3 O 8 + Fe 2 O 3 aerosols from the atmosphere of the NSPP vessel by steam-air is probably caused by the change in aerosol shape and the condensation of steam on the aerosol surfaces combining to increase the effect of gravitational settling. The apparent lack of an effect by steam-air on the removal rate of concrete aerosol could result from a differing physical/chemical response of the surfaces of this aerosol to condensing steam

From basic concepts to emerging technologies in regional anesthesia.

Science.gov (United States)

Dillane, Derek; Tsui, Ban C H

2010-10-01

The present article details how our understanding of the basic concepts of regional anesthesia has recently evolved. We will appraise current technological advances and question the commensurate nature of the relationship between tradition and innovation. Ultrasound localization has enhanced our understanding of the needle-nerve relationship. Intraneural injection of local anesthetic may occur with greater frequency than previously thought without inevitably leading to neurological complications. The ratio of neural to non-neural tissue varies both between and within nerves and may be an important determinant of neural injury. Ultrasonographic evidence of intraneural injection is subject to observer expertise and the resolution of the ultrasound image. Current ultrasound resolution capability does not reliably permit differentiation between intrafascicular and extrafascicular drug injection. Perineural electrical impedance may be a determinant of current threshold and conceivably distinguish between intraneural and extraneural tissue. Technology that enhances the sonographic image of both procedure needle and target nerve is the focus of current endeavors in ultrasound innovation.There is inconclusive evidence that the use of ultrasound technology has reduced the incidence of local anesthetic toxicity. Lipid emulsion therapy is now an accepted treatment for systemic local anesthetic toxicity. There are new reports on the development of an ultra long-acting local anesthetic agent that would permit lower doses and superannuate catheter-based continuous regional anesthesia techniques. Over the past decade, our understanding of the fundamental concepts of regional anesthesia continues to be challenged by emerging experimental and clinical evidence.

Assimilation of Polder aerosol optical thickness into LMD2-Inca model in order to study aerosol-climate interactions; Etude des interactions entre aerosols et climat: assimilation des observations spatiales de Polder dans LMDz-Inca

Energy Technology Data Exchange (ETDEWEB)

Generoso, S.

2004-12-15

Aerosols influence the Earth radiative budget both through their direct (scattering and absorption of solar radiation) and indirect (impacts on cloud microphysics) effects. The anthropogenic perturbation due to aerosol emissions is of the same order of magnitude than the one due to greenhouse gases, but less well known. To improve our knowledge, we need to better know aerosol spatial and temporal distributions. Indeed, aerosol modeling still suffers from large uncertainties in sources and transport, while satellite observations are incomplete (no detection in the presence of clouds, no information on the vertical distribution or on the chemical nature). Moreover, field campaigns are localized in space and time. This study aims to reduce uncertainties in aerosol distributions, developing assimilation of satellite data into a chemical transport model. The basic idea is to combine information obtained from spatial observation (optical thickness) and modeling studies (aerosol types, vertical distribution). In this study, we assimilate data from the POLDER space-borne instrument into the LMDz-INCA model. The results show the advantage of merging information from different sources. In many regions, the method reduces uncertainties on aerosol distribution (reduction of RMS error). An application of the method to the study of aerosol impact on cloud microphysics is shown. (author)

Evaluation of the basic concepts of approaches for the coexistence of nuclear energy and people/local community

International Nuclear Information System (INIS)

Kondo, Shunsuke; Kuroki, Shinichi; Nakagiri, Yuko

2007-01-01

In November 2007, the Policy Evaluation Committee compiled the report, which evaluated the basic concepts of approaches to the coexistence of nuclear energy and people/local community, specified in the Framework for Nuclear Energy Policy. The report states that the 'concerned administrative bodies are carrying out measures related to the coexistence of nuclear energy and people/local communities in line with these basic concept' and summarizes fifteen proposals conductive to the betterment and improvement of these measures, which were classified as 1) secure transparency and promotion of mutual understanding with the public, 2) development and enrichment of learning opportunities and public participation, 3) relationship between the government and local governments and 4) coexistence with local residents. The Japan Atomic Energy Commission (JAEC) considers this report to be reasonable. This article presented an overview of this activity. (T. Tanaka)

Aerosol Effects on Instability, Circulations, Clouds, and Precipitation

Directory of Open Access Journals (Sweden)

Seoung-Soo Lee

2014-01-01

Full Text Available It is well known that increasing aerosol and associated changes in aerosol-cloud interactions and precipitation since industrialization have been playing an important role in climate change, but this role has not been well understood. This prevents us from predicting future climate with a good confidence. This review paper presents recent studies on the changes in the aerosol-cloud interactions and precipitation particularly in deep convective clouds. In addition, this review paper discusses how to improve our understanding of these changes by considering feedbacks among aerosol, cloud dynamics, cloud and its embedded circulations, and microphysics. Environmental instability basically determines the dynamic intensity of clouds and thus acts as one of the most important controls on these feedbacks. As a first step to the improvement of the understanding, this paper specifically elaborates on how to link the instability to the feedbacks.

A new look at some basic concepts in arbitrage pricing theory

Institute of Scientific and Technical Information of China (English)

XIA; Jianming(夏建明); YAN; Jia'an(严加安)

2003-01-01

The notion of No Free Lunch with Vanishing Risk (or NFLVR in short) w.r.t. admissible strategies depends on the choice of numeraire. Yan introduced the notion of allowable strategy and showed that condition of NFLVR w.r.t. allowable strategies is independent of the choice of numeraire and is equivalent to the existence of an equivalent martingale measure for the deflated price process. In this paper we establish a version of the Kramkov's optional decomposition theorem in the setting of equivalent martingale measures. Based on this theorem, we have a new look at some basic concepts in arbitrage pricing theory: superhedging, fair price,attainable contingent claims, complete markets and etc.

Basic concepts in computational physics

CERN Document Server

Stickler, Benjamin A

2016-01-01

This new edition is a concise introduction to the basic methods of computational physics. Readers will discover the benefits of numerical methods for solving complex mathematical problems and for the direct simulation of physical processes. The book is divided into two main parts: Deterministic methods and stochastic methods in computational physics. Based on concrete problems, the first part discusses numerical differentiation and integration, as well as the treatment of ordinary differential equations. This is extended by a brief introduction to the numerics of partial differential equations. The second part deals with the generation of random numbers, summarizes the basics of stochastics, and subsequently introduces Monte-Carlo (MC) methods. Specific emphasis is on MARKOV chain MC algorithms. The final two chapters discuss data analysis and stochastic optimization. All this is again motivated and augmented by applications from physics. In addition, the book offers a number of appendices to provide the read...

Air ions and aerosol science

International Nuclear Information System (INIS)

Tammet, H.

1996-01-01

Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4 endash 1.8 nm. copyright 1996 American Institute of Physics

Basic concept on safety regulation for land disposal of low level radioactive solid wastes

International Nuclear Information System (INIS)

1985-01-01

As to the land disposal of low level radioactive solid wastes, to which the countermeasures have become the urgent problem at present, it is considered to be a realistic method to finally store the solid wastes concentratedly outside the sites of nuclear power stations and others, and effort has been exerted by those concerned to realize it. Besides, as for extremely low level radioactive solid wastes, the measures of disposing them corresponding to the radioactivity level are necessary, and the concrete method has been examined. The Committee on Safety Regulation for Radioactive Wastes has discussed the safety regulation for those since April, 1984, and the basic concept on the safety regulation was worked up. It is expected that the safety of the land disposal of low level radioactive solid wastes can be ensured when the safety regulation is carried out in conformity with this basic concept. The present status of the countermeasures to the land disposal of low level radioactive solid wastes is shown. As the concrete method, the disposal in shallow strate has been generally adopted. At present, the plan for the final storage in Aomori Prefecture is considered, and it will be started with the first stage of four-stage control. (Kako, I.)

Novel concept for neutron detection: proportional counter filled with 10B nanoparticle aerosol

Science.gov (United States)

Amaro, F. D.; Monteiro, C. M. B.; dos Santos, J. M. F.; Antognini, A.

2017-01-01

The high neutron detection efficiency, good gamma-ray discrimination and non-toxicity of 3He made of proportional counters filled with this gas the obvious choice for neutron detection, particularly in radiation portal monitors (RPM), used to control the illicit transport of nuclear material, of which neutron detectors are key components. 3He is very rare and during the last decade this gas has become increasingly difficult to acquire. With the exception of BF3, which is toxic, no other gas can be used for neutron detection in proportional counters. We present an alternative where the 3He atoms are replaced by nanoparticles made of another neutron sensitive material, 10B. The particles are dispersed in a gaseous volume, forming an aerosol with neutron sensitive properties. A proportional counter filled with such aerosol was exposed to a thermal neutron beam and the recorded response indicates that the neutrons have interacted with the particles in the aerosol. This original technique, which transforms a standard proportional gas mixture into a neutron sensitive aerosol, is a breakthrough in the field of radiation detection and has the potential to become an alternative to the use of 3He in proportional counters. PMID:28181520

The Use of Remote Sensing to Resolve the Aerosol Radiative Forcing

Science.gov (United States)

Kaufman, Y. J.; Tanre, D.; Remer, Lorraine

1999-01-01

Satellites are used for remote sensing of aerosol optical thickness and optical properties in order to derive the aerosol direct and indirect radiative forcing of climate. Accuracy of the derived aerosol optical thickness is used as a measure of the accuracy in deriving the aerosol radiative forcing. Several questions can be asked to challenge this concept. Is the accuracy of the satellite-derived aerosol direct forcing limited to the accuracy of the measured optical thickness? What are the spectral bands needed to derive the total aerosol forcing? Does most of the direct or indirect aerosol forcing of climate originate from regions with aerosol concentrations that are high enough to be detected from space? What should be the synergism ground-based and space-borne remote sensing to solve the problem? We shall try to answer some of these questions, using AVIRIS airborne measurements and simulations.

Realization of nuclear track filters and their applications to the study of environmental aerosol samples

International Nuclear Information System (INIS)

Guo Shilun

1993-01-01

Detailed study of the behaviours of radon decay products requires the knowledge of environmental aerosols. A combination of devices and instruments have been tested to be superior in study of aerosol characteristics. Nuclear track filters and cascade track filter impactor are basic devices, which bring the functions of α -spectrometer, scanning electron microscope and electron microprobe into full play. This paper describes how to use these devices and instruments to collect aerosols, to determine aerosol radioactivity, size distribution and elemental compositions and to determine the concentration of aerosols in air as a function of aerosol sizes, which are important parameters in dominating the interactions between aerosol and radon decay products. (author). 15 refs, 7 figs

Multistatic Aerosol Cloud Lidar in Space: A Theoretical Perspective

Science.gov (United States)

Mishchenko, Michael I.; Alexandrov, Mikhail D.; Cairns, Brian; Travis, Larry D.

2016-01-01

Accurate aerosol and cloud retrievals from space remain quite challenging and typically involve solving a severely ill-posed inverse scattering problem. In this Perspective, we formulate in general terms an aerosol and aerosol-cloud interaction space mission concept intended to provide detailed horizontal and vertical profiles of aerosol physical characteristics as well as identify mutually induced changes in the properties of aerosols and clouds. We argue that a natural and feasible way of addressing the ill-posedness of the inverse scattering problem while having an exquisite vertical-profiling capability is to fly a multistatic (including bistatic) lidar system. We analyze theoretically the capabilities of a formation-flying constellation of a primary satellite equipped with a conventional monostatic (backscattering) lidar and one or more additional platforms each hosting a receiver of the scattered laser light. If successfully implemented, this concept would combine the measurement capabilities of a passive multi-angle multi-spectral polarimeter with the vertical profiling capability of a lidar; address the ill-posedness of the inverse problem caused by the highly limited information content of monostatic lidar measurements; address the ill-posedness of the inverse problem caused by vertical integration and surface reflection in passive photopolarimetric measurements; relax polarization accuracy requirements; eliminate the need for exquisite radiative-transfer modeling of the atmosphere-surface system in data analyses; yield the day-and-night observation capability; provide direct characterization of ground-level aerosols as atmospheric pollutants; and yield direct measurements of polarized bidirectional surface reflectance. We demonstrate, in particular, that supplementing the conventional backscattering lidar with just one additional receiver flown in formation at a scattering angle close to 170deg can dramatically increase the information content of the

Teaching Basic Programming Concepts to Young Primary School Students Using Tablets: Results of a Pilot Project

Science.gov (United States)

Fokides, Emmanuel

2018-01-01

The study presents the results of a project in which tablets and a ready-made application were used for teaching basic programming concepts to young primary school students (ages 7-9). A total of 135 students participated in the study, attending primary schools in Athens, Greece, divided into three groups. The first was taught conventionally. The…

Badminton--Teaching Concepts.

Science.gov (United States)

Gibbs, Marilyn J.

1988-01-01

Teaching four basic badminton concepts along with the usual basic skill shots allows players to develop game strategy awareness as well as mechanical skills. These four basic concepts are: (1) ready position, (2) flight trajectory, (3) early shuttle contact, and (4) camouflage. (IAH)

The Effect of Using an Educational Website in Achievement of Bachelor Students in the Course of Basic Concepts in Mathematics at Al al-Bayt University

Science.gov (United States)

Qudah, Ahmad Hassan

2016-01-01

The study aimed to detect the effect of using an educational site on the Internet in the collection of bachelor's students in the course of basic concepts in mathematics at Al al-Bayt University, and the study sample consisted of all students in the course basic concepts in mathematics in the first semester of the academic year 2014/2015 and the…

Basic concept of common reactor physics code systems. Final report of working party on common reactor physics code systems (CCS)

International Nuclear Information System (INIS)

2004-03-01

A working party was organized for two years (2001-2002) on common reactor physics code systems under the Research Committee on Reactor Physics of JAERI. This final report is compilation of activity of the working party on common reactor physics code systems during two years. Objectives of the working party is to clarify basic concept of common reactor physics code systems to improve convenience of reactor physics code systems for reactor physics researchers in Japan on their various field of research and development activities. We have held four meetings during 2 years, investigated status of reactor physics code systems and innovative software technologies, and discussed basic concept of common reactor physics code systems. (author)

Fission-fragment attachment to aerosols and their transport through capillary tubes

International Nuclear Information System (INIS)

Novick, V.J.; Alvarez, J.L.; Greenwood, R.C.

1981-01-01

The transport of radioactive aerosols was studied using equipment, collectively called the Helium jet, that has been constructed to provide basic nuclear physics data on fission product nuclides. The transport of the fission products in the system depends on their attachment to aerosol particles. The system consists of 1) a tube furnace which generates aerosols by the sublimation or evaporation of source material, 2) a helium stream used to transport the aerosols, 3) a 25 m settling tube to eliminate the larger aerosols and smaller aerosols that would deposit in the capillary, 4) a Californium-252 self-fissioning source of fission product nuclides, and 5) a small capillary to carry the radioactive aerosols from the hot cell to the laboratory. Different source materials were aerosolized but NaCl is generally used because it yielded the highest transport efficiencies through the capillary. Particle size measurments were made with NaCl aerosols by using a cascade impactor, an optical light scattering device, and the capillary itself as a diffusion battery by performing radiation measurements and/or electrical conductivity measurements. Both radioactive and nonradioactive aerosols were measured in order to investigate the possibility of a preferential size range for fission product attachment. The measured size distributions were then used to calculate attachment coefficients and finally an attachment time

Characterization of regional atmospheric aerosols over Hungary by PIXE elemental analysis

International Nuclear Information System (INIS)

Koltay, E.; Szabo, G.; Borbely Kiss, I.; Somorjai, E.; Kiss, A.Z.

1994-01-01

Studying the characteristic features of atmospheric aerosols emitted by natural and anthropogenic sources is of basic importance for a detailed understanding of the physics and chemistry of the atmosphere. Environmental pollution by atmospheric aerosols and their impact can be tested in the same way, too. The separation of natural and anthropogenic components of the aerosol can be done through enrichment factors and size distribution curves deduced from analytical information. The Particle Induced X-ray Emission (PIXE) technique has been applied in aerosol studies by the authors. Results obtained on atmospheric aerosols collected over Hungary and presented in terms of concentrations, enrichment factors, regional signatures, deposition velocities, transport properties and apportionment of sources illustrate the scope and proportions of the potential contribution of PIXE to the methodology of atmospheric aerosol studies. Continued activity planned in the framework of the present CRP may widen the scope of the investigations mainly in the field of size-fractioned sampling and - possibly - in the direction of individual characterization of aerosol particles. (author). 14 refs

Virtual laboratory learning media development to improve science literacy skills of mechanical engineering students on basic physics concept of material measurement

Science.gov (United States)

Jannati, E. D.; Setiawan, A.; Siahaan, P.; Rochman, C.

2018-05-01

This study aims to determine the description of virtual laboratory learning media development to improve science literacy skills of Mechanical Engineering students on the concept of basic Physics. Quasi experimental method was employed in this research. The participants of this research were first semester students of mechanical engineering in Majalengka University. The research instrument was readability test of instructional media. The results of virtual laboratory learning media readability test show that the average score is 78.5%. It indicates that virtual laboratory learning media development are feasible to be used in improving science literacy skill of Mechanical Engineering students in Majalengka University, specifically on basic Physics concepts of material measurement.

Detection and quantification limits: basic concepts, international harmonization, and outstanding ('low-level') issues

International Nuclear Information System (INIS)

Currie, L.A.

2004-01-01

A brief review is given of concepts, basic definitions, and terminology for metrological detection and quantification capabilities, representing harmonized recommendations and norms of the International Union of Pure and Applied Chemistry (IUPAC) and the International Organization for Standardization (ISO), respectively. Treatment of the (low-level) blank and variance function are discussed in some detail, together with special problems arising with detection decisions and the reporting of low-level data. Key references to the international documents follow, as well as specialized references addressing very low-level counting data, skewed environmental blank distributions, and multiple and multivariate detection decisions

Spatial Interpolation of Aerosol Optical Depth Pollution: Comparison of Methods for the Development of Aerosol Distribution

Science.gov (United States)

Safarpour, S.; Abdullah, K.; Lim, H. S.; Dadras, M.

2017-09-01

Air pollution is a growing problem arising from domestic heating, high density of vehicle traffic, electricity production, and expanding commercial and industrial activities, all increasing in parallel with urban population. Monitoring and forecasting of air quality parameters are important due to health impact. One widely available metric of aerosol abundance is the aerosol optical depth (AOD). The AOD is the integrated light extinction coefficient over a vertical atmospheric column of unit cross section, which represents the extent to which the aerosols in that vertical profile prevent the transmission of light by absorption or scattering. Seasonal aerosol optical depth (AOD) values at 550 nm derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard NASA's Terra satellites, for the 10 years period of 2000 - 2010 were used to test 7 different spatial interpolation methods in the present study. The accuracy of estimations was assessed through visual analysis as well as independent validation based on basic statistics, such as root mean square error (RMSE) and correlation coefficient. Based on the RMSE and R values of predictions made using measured values from 2000 to 2010, Radial Basis Functions (RBFs) yielded the best results for spring, summer and winter and ordinary kriging yielded the best results for fall.

SPATIAL INTERPOLATION OF AEROSOL OPTICAL DEPTH POLLUTION: COMPARISON OF METHODS FOR THE DEVELOPMENT OF AEROSOL DISTRIBUTION

Directory of Open Access Journals (Sweden)

S. Safarpour

2017-09-01

Full Text Available Air pollution is a growing problem arising from domestic heating, high density of vehicle traffic, electricity production, and expanding commercial and industrial activities, all increasing in parallel with urban population. Monitoring and forecasting of air quality parameters are important due to health impact. One widely available metric of aerosol abundance is the aerosol optical depth (AOD. The AOD is the integrated light extinction coefficient over a vertical atmospheric column of unit cross section, which represents the extent to which the aerosols in that vertical profile prevent the transmission of light by absorption or scattering. Seasonal aerosol optical depth (AOD values at 550 nm derived from the Moderate Resolution Imaging Spectroradiometer (MODIS sensor onboard NASA’s Terra satellites, for the 10 years period of 2000 - 2010 were used to test 7 different spatial interpolation methods in the present study. The accuracy of estimations was assessed through visual analysis as well as independent validation based on basic statistics, such as root mean square error (RMSE and correlation coefficient. Based on the RMSE and R values of predictions made using measured values from 2000 to 2010, Radial Basis Functions (RBFs yielded the best results for spring, summer and winter and ordinary kriging yielded the best results for fall.

Elemental mass size distribution of the Debrecen urban aerosol

International Nuclear Information System (INIS)

Kertesz, Zs.; Szoboszlai, Z.; Dobos, E.; Borbely-Kiss, I.

2007-01-01

Complete text of publication follows. Size distribution is one of the basic properties of atmospheric aerosol. It is closely related to the origin, chemical composition and age of the aerosol particles, and it influences the optical properties, environmental effects and health impact of aerosol. As part of the ongoing aerosol research in the Group of Ion Beam Applications of the Atomki, elemental mass size distribution of urban aerosol were determined using particle induced X-ray emission (PIXE) analytical technique. Aerosol sampling campaigns were carried out with 9-stage PIXE International cascade impactors, which separates the aerosol into 10 size fractions in the 0.05-30 ?m range. Five 48-hours long samplings were done in the garden of the Atomki, in April and in October, 2007. Both campaigns included weekend and working day samplings. Basically two different kinds of particles could be identified according to the size distribution. In the size distribution of Al, Si, Ca, Fe, Ba, Ti, Mn and Co one dominant peak can be found around the 3 m aerodynamic diameter size range, as it is shown on Figure 1. These are the elements of predominantly natural origin. Elements like S, Cl, K, Zn, Pb and Br appears with high frequency in the 0.25-0.5 mm size range as presented in Figure 2. These elements are originated mainly from anthropogenic sources. However sometimes in the size distribution of these elements a 2 nd , smaller peak appears at the 2-4 μm size ranges, indicating different sources. Differences were found between the size distribution of the spring and autumn samples. In the case of elements of soil origin the size distribution was shifted towards smaller diameters during October, and a 2 nd peak appeared around 0.5 μm. A possible explanation to this phenomenon can be the different meteorological conditions. No differences were found between the weekend and working days in the size distribution, however the concentration values were smaller during the weekend

The concepts of exclusion, exemption and clearance as used in the interagency basic safety standards and related IAEA documents

International Nuclear Information System (INIS)

Webbl, G.A.M.

1997-01-01

Mechanisms are needed to remove from regulatory control those exposures or radiation sources that do not warrant concern. In this paper three such conceptual mechanisms are examined from their historical development to their current usage in the Interagency Basic Safety Standards. These concepts are exclusion, applied to exposures that are not amenable to control, exemption applied in advance on the basis of low risks to prevent practices or sources from entering the regulatory control system, and clearance, a similar concept but used to remove sources from the regulatory control system. The application of and interrelationships between these concepts, is described. (author)

Basic Concepts for rethinking environmental issues

International Nuclear Information System (INIS)

Gonzalez Ladron de Guevara, Francisco Jose; Valencia Cuellar, Jorge

2013-01-01

This article presents a review of the fundamental concepts from which environmental problems have been explained and solved during the last decades. Environment is understood as an encounter between nature and culture that is a social construct that reflects the interaction between human beings and the biophysical space in which they live. On the other hand, development is conceived as the ability that societies have to develop their potentialities, being a notion of a totalizing and ethical political nature, which incorporates the biophysical and social heritage of a certain society. Regarding the concept of culture, it must be said that it is built upon the basis that this is an adaptive strategy of the human species. Finally, the relationships between the concepts of culture, environment and development are studied in order to formulate a new perspective for rethinking the environmental issue, so that, in turn, it could be used to redirect survival strategies that human beings currently apply in their interaction with the environment.

Structural equation modeling with LISREL, PRELIS, and SIMPLIS basic concepts, applications, and programming

CERN Document Server

Byrne, Barbara M

2013-01-01

This book illustrates the ease with which various features of LISREL 8 and PRELIS 2 can be implemented in addressing research questions that lend themselves to SEM. Its purpose is threefold: (a) to present a nonmathmatical introduction to basic concepts associated with SEM, (b) to demonstrate basic applications of SEM using both the DOS and Windows versions of LISREL 8, as well as both the LISREL and SIMPLIS lexicons, and (c) to highlight particular features of the LISREL 8 and PRELIS 2 progams that address important caveats related to SEM analyses. This book is intended neither as a text on the topic of SEM, nor as a comprehensive review of the many statistical funcitons available in the LISREL 8 and PRELIS 2 programs. Rather, the intent is to provide a practical guide to SEM using the LISREL approach. As such, the reader is "walked through" a diversity of SEM applications that include both factor analytic and full latent variable models, as well as a variety of data management procedures.

Nonsymmetric entropy I: basic concepts and results

OpenAIRE

Liu, Chengshi

2006-01-01

A new concept named nonsymmetric entropy which generalizes the concepts of Boltzman's entropy and shannon's entropy, was introduced. Maximal nonsymmetric entropy principle was proven. Some important distribution laws were derived naturally from maximal nonsymmetric entropy principle.

The Learning of Science Basic Concept by Using Scientifiq Inquiry to Improve Student’s Thinking, Working, and Scientific Attitude Abilities

Directory of Open Access Journals (Sweden)

Wachidatul Linda Yuhanna

2016-03-01

Full Text Available This research was a classroom action research which was conducted intwo cycles, each cycle consists of planning, implementing, observing, and reflecting. The data used was quantitative data on student observation sheet instruments. The Results of the study which were obtained from the first cycle showed about the students’ thinking skills and scientific works. They were categorized as excellent 18.18%, good 22.73%, enough 52.27%, and sufficiently less 6.82%. As for the scientific attitude with a very active category of 11.36%, 43.18% and less active 45.45%. It has not reached indicators of success, so it was necessary to cycle II. Cycle II demonstrated the excellent category 38.63%, 36.36% good, good enough18.18% and less 6.81%. While the scientific attitude in the cycle II was an active attitude 29.54%, active 54.54%, inactive 15.91%. These results show an increase from the cycle I to cycle II. The conclusion of this study were: 1 learning the basic concepts of science with scientific inquiry in students can be conducible applied.2 Learning the basic concepts of science with scientific inquiry can improve thinking ability and scientific work and students’ scientific attitude. 3 Learning the basic concepts of science with scientific inquiry be able to explore and develop student creativity in designing simple experiments which can be applied in primary schools.

The Past Almost Half-Century Landing On The Moon And Still Countering Basic Astronomy Conceptions

OpenAIRE

Türkmen, Hakan

2015-01-01

The purpose of study is to investigate the fifth graders’ understandings of the basic astronomy concept and, if they have, to define their misconceptions and then to determine what reason/s behind them. For this purpose, two hundred seventy fifth grade students from 6 different schools participated. Randomly selected 45 students performing under the class average and 6 teachers were interviewed to determine what reason/s behind students’ misconceptions. The results of study showed that many 5...

The Mediational Role of Psychological Basic Needs in the Relation Between Conception of God and Psychological Outcomes.

Science.gov (United States)

Costa, Sebastiano; Gugliandolo, Maria C; Barberis, Nadia; Larcan, Rosalba

2016-02-01

Relatively few studies have examined the relationship between conception of God and psychological outcomes in a self-determination theory (SDT) framework. The aim of this study was to examine the role of basic psychological needs as a mediator of the association between conception of God and psychological outcomes. In a sample of 210 religious young adults, we found that the concept of a controlling God was positively associated with feelings of need frustration and depression, whilst the concept of an autonomy-supporting God was positively associated with feelings of need satisfaction and vitality. In turn, need satisfaction promoted feelings of vitality, whereas need frustration led to feelings of depression. The satisfaction of needs was a full mediator of the relationship between autonomy-supporting God and vitality, whilst the frustration of needs was a full mediator of the relationship between controlling God and depression. These findings are discussed in terms of SDT. We also discuss how future research may further increase our understanding of the dynamics involved in concepts of God and psychological outcomes.

Tropospheric Aerosols

Science.gov (United States)

Buseck, P. R.; Schwartz, S. E.

2003-12-01

It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, aerosols - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of aerosol particles per cubic meter of air.Atmospheric aerosols are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. Aerosol particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background aerosol has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric aerosols in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by aerosols. Photographs at Yosemite National Park, California, USA. (a) Low aerosol concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10 �

Analysis of intensive aerosol optical properties measured at the Jungfraujoch station

Energy Technology Data Exchange (ETDEWEB)

Li, F.; Nyeki, S.; Baltensperger, U.; Weingartner, E.; Lugauer, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

Characterisation of atmospheric aerosol optical properties at the Jungfraujoch has been conducted to deliver basic data for comparison with those from NOAA baseline atmospheric monitoring stations. (author) 2 figs., 2 refs.

Aerosol scrubbers

International Nuclear Information System (INIS)

Sheely, W.F.

1986-01-01

The Submerged Gravel Scrubber is an air cleaning system developed by the Department of Energy's Liquid Metal Reactor Program. The Scrubber System has been patented by the Department of Energy. This technology is being transferred to industry by the DOE. Its basic principles can be adapted for individual applications and the commercialized version can be used to perform a variety of tasks. The gas to be cleaned is percolated through a continuously washed gravel bed. The passage of the gas through the gravel breaks the stream into many small bubbles rising in a turbulent body of water. These conditions allow very highly efficient removal of aerosols from the gas

Aerosol absorption measurement with a sinusoidal phase modulating fiber optic photo thermal interferometer

Science.gov (United States)

Li, Shuwang; Shao, Shiyong; Mei, Haiping; Rao, Ruizhong

2016-10-01

Aerosol light absorption plays an important role in the earth's atmosphere direct and semi-direct radiate forcing, simultaneously, it also has a huge influence on the visibility impairment and laser engineering application. Although various methods have been developed for measuring aerosol light absorption, huge challenge still remains in precision, accuracy and temporal resolution. The main reason is that, as a part of aerosol light extinction, aerosol light absorption always generates synchronously with aerosol light scattering, and unfortunately aerosol light scattering is much stronger in most cases. Here, a novel photo-thermal interferometry is proposed only for aerosol absorption measurement without disturbance from aerosol scattering. The photo-thermal interferometry consists of a sinusoidal phase-modulating single mode fiber-optic interferometer. The thermal dissipation, caused by aerosol energy from photo-thermal conversion when irritated by pump laser through interferometer, is detected. This approach is completely insensitive to aerosol scattering, and the single mode fiber-optic interferometer is compact, low-cost and insensitive to the polarization shading. The theory of this technique is illustrated, followed by the basic structure of the sinusoidal phase-modulating fiber-optic interferometer and demodulation algorithms. Qualitative and quantitative analysis results show that the new photo-thermal interference is a potential approach for aerosol absorption detection and environmental pollution detection.

Effect of Wind Speed on Aerosol Optical Depth over Remote Oceans, Based on Data from the Maritime Aerosol Network

Science.gov (United States)

Smirnov, A.; Sayer, A. M.; Holben, B. N.; Hsu, N. C.; Sakerin, S. M.; Macke, A.; Nelson, N. B.; Courcoux, Y.; Smyth, T. J.; Croot, P.;

Basic Concepts of CNS Development.

Science.gov (United States)

Nowakowski, R. S.

1987-01-01

The goals of this review are to: (1) provide a set of concepts to aid in the understanding of complex processes which occur during central nervous system (CNS) development; (2) illustrate how they contribute to our knowlege of adult brain anatomy; and (3) delineate how modifications of normal developmental processes may affect the structure and…

Analysis of Students' Conceptions of Basic Magnetism from a Complex Systems Perspective

Science.gov (United States)

Lemmer, Miriam; Kriek, Jeanne; Erasmus, Benita

2018-03-01

This study established whether 12 South African secondary school physics students had incorrect conceptions of basic magnetism and if they had, to what extent they consistently applied such conceptions. Different scenarios in the form of thought experiments were presented in a clinical interview approach. A complex systems perspective underpinned the study and was firstly used to analyze 12 students' conceptions in terms of intuitive fragments of knowledge elements, structured misconceptions, and theory-like system of knowledge elements. Secondly, coherence in each student's ideas expressed across ten themes using thought experiments was analyzed in an effort to determine variations or coherence in responses. Examples of student explanations and sketches are discussed in the paper to illustrate the conceptual structures they applied. Most of the students in this study used a variety of knowledge elements in accord with a complex systems perspective, but three students seemed to prefer a specific perspective. One student's ideas tended to be mainly fragmented, a second exposed a number of structured misconceptions, while another student's reasoning can be described as a theory-like system of knowledge elements. Accordingly, the emphasis of physics education research should no longer be on the compilation of a list of misconceptions that have to be remedied or replaced, but on the conceptual connections, students make and their associative reasoning patterns (i.e., knowledge systems revealed). It remains for the teacher to use the complex systems perspective as a framework to facilitate students' conceptual development and understanding, proceeding on their existing knowledge systems.

Implementation of basic chemistry experiment based on metacognition to increase problem-solving and build concept understanding

Science.gov (United States)

Zuhaida, A.

2018-04-01

Implementation of the experiment have the three aspects of the goal: 1) develop basic skills of experimenting; 2) develop problem-solving skills with a scientific approach; 3) improve understanding of the subject matter. On the implementation of the experiment, students have some weaknesses include: observing, identifying problems, managing information, analyzing, and evaluating. This weakness is included in the metacognition indicator.The objective of the research is to implementation of Basic Chemistry Experiment based on metacognition to increase problem-solving skills and build concept understanding for students of Science Education Department. The method of this research is a quasi- experimental method with pretest-posttest control group design. Problem-solving skills are measured through performance assessments using rubrics from problem solving reports, and results presentation. The conceptual mastery is measured through a description test. The result of the research: (1) improve the problem solving skills of the students with very high category; (2) increase the students’ concept understanding better than the conventional experiment with the result of N-gain in medium category, and (3) increase student's response positively for learning implementation. The contribution of this research is to extend the implementation of practical learning for some subjects, and to improve the students' competence in science.

Structural equation modeling with EQS basic concepts, applications, and programming

CERN Document Server

Byrne, Barbara M

2013-01-01

Readers who want a less mathematical alternative to the EQS manual will find exactly what they're looking for in this practical text. Written specifically for those with little to no knowledge of structural equation modeling (SEM) or EQS, the author's goal is to provide a non-mathematical introduction to the basic concepts of SEM by applying these principles to EQS, Version 6.1. The book clearly demonstrates a wide variety of SEM/EQS applications that include confirmatory factor analytic and full latent variable models. Written in a "user-friendly" style, the author "walks" the reader through the varied steps involved in the process of testing SEM models: model specification and estimation, assessment of model fit, EQS output, and interpretation of findings. Each of the book's applications is accompanied by: a statement of the hypothesis being tested, a schematic representation of the model, explanations of the EQS input and output files, tips on how to use the pull-down menus, and the data file upon which ...

Hydromechanics - basic properties

International Nuclear Information System (INIS)

Lee, Sung Tak; Lee, Je Geun

1987-03-01

This book tells of hydromechanics, which is about basic properties of hydromechanics such as conception, definition, mass, power and weight, and perfect fluid and perfect gas, hydrostatics with summary, basic equation of hydrostatics, relative balance of hydrostatics, and kinematics of hydromechanics, description method of floating, hydromechanics about basic knowledge, equation of moment, energy equation and application of Bernoulli equation, application of momentum theory, inviscid flow and fluid measuring.

Manifestation of Aerosol Indirect Effects in Arctic Clouds

Science.gov (United States)

Lubin, D.; Vogelmann, A. M.

2009-12-01

The first aerosol indirect effect has traditionally been conceived as an enhancement of shortwave cloud reflectance in response to decreased effective droplet size at fixed liquid water path, as cloud nucleating aerosol becomes entrained in the cloud. The high Arctic, with its pervasive low-level stratiform cloud cover and frequent episodes of anthropogenic aerosol (Artic "haze"), has in recent years served as a natural laboratory for research on actual manifestations of aerosol indirect effects. This paper will review the surprising set of developments: (1) the detection of the indirect effect as a source of surface warming, rather than cooling, throughout early spring, (2) a transition to a cooling effect in late spring, corresponding to the beginning of the sea ice melt season, and (3) detection of an indirect effect during summer, outside of the "Arctic haze" season. This paper will also discuss measurements of spectral shortwave irradiance (350-2200 nm) made at Barrow, Alaska, during the U.S. Department of Energy's Indirect and Semi-Direct Aerosol Campaign (ISDAC), which reveal complications in our conception of the indirect effect related to the ice phase in Arctic stratiform clouds.

Wavelet basics

CERN Document Server

Chan, Y T

1995-01-01

Since the study of wavelets is a relatively new area, much of the research coming from mathematicians, most of the literature uses terminology, concepts and proofs that may, at times, be difficult and intimidating for the engineer. Wavelet Basics has therefore been written as an introductory book for scientists and engineers. The mathematical presentation has been kept simple, the concepts being presented in elaborate detail in a terminology that engineers will find familiar. Difficult ideas are illustrated with examples which will also aid in the development of an intuitive insight. Chapter 1 reviews the basics of signal transformation and discusses the concepts of duals and frames. Chapter 2 introduces the wavelet transform, contrasts it with the short-time Fourier transform and clarifies the names of the different types of wavelet transforms. Chapter 3 links multiresolution analysis, orthonormal wavelets and the design of digital filters. Chapter 4 gives a tour d'horizon of topics of current interest: wave...

Basic hydraulics

CERN Document Server

Smith, P D

1982-01-01

BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

Alfred-Adler's Basic Concepts and Implications.

Science.gov (United States)

Lundin, Robert W.

This book presents the basic principles of Adler's psychology. The first chapter looks at Adlerian psychology as it exists today, and examines earlier influences. The second chapter examines feelings of inferiority and compensation for these feelings. The third chapter considers the nature of goals and how they are formulated. The fourth chapter…

Development and Validation of the Life Sciences Assessment: A Measure of Preschool Children's Conceptions of Basic Life Sciences

Science.gov (United States)

Maherally, Uzma Nooreen

2014-01-01

The purpose of this study was to develop and validate a science assessment tool termed the Life Sciences Assessment (LSA) in order to assess preschool children's conceptions of basic life sciences. The hypothesis was that the four sub-constructs, each of which can be measured through a series of questions on the LSA, will make a significant…

Partial least squares path modeling basic concepts, methodological issues and applications

CERN Document Server

Noonan, Richard

2017-01-01

This edited book presents the recent developments in partial least squares-path modeling (PLS-PM) and provides a comprehensive overview of the current state of the most advanced research related to PLS-PM. The first section of this book emphasizes the basic concepts and extensions of the PLS-PM method. The second section discusses the methodological issues that are the focus of the recent development of the PLS-PM method. The third part discusses the real world application of the PLS-PM method in various disciplines. The contributions from expert authors in the field of PLS focus on topics such as the factor-based PLS-PM, the perfect match between a model and a mode, quantile composite-based path modeling (QC-PM), ordinal consistent partial least squares (OrdPLSc), non-symmetrical composite-based path modeling (NSCPM), modern view for mediation analysis in PLS-PM, a multi-method approach for identifying and treating unobserved heterogeneity, multigroup analysis (PLS-MGA), the assessment of the common method b...

Aerosol lung inhalation scintigraphy in normal subjects

Energy Technology Data Exchange (ETDEWEB)

Sui, Osamu; Shimazu, Hideki

1985-03-01

We previously reported basic and clinical evaluation of aerosol lung inhalation scintigraphy with /sup 99m/Tc-millimicrosphere albumin (milli MISA) and concluded aerosol inhalation scintigraphy with /sup 99m/Tc-milli MISA was useful for routine examination. But central airway deposit of aerosol particles was found in not only the patients with chronic obstructive pulmonary disease (COPD) but also normal subjects. So we performed aerosol inhalation scintigraphy in normal subjects and evaluated their scintigrams. The subjects had normal values of FEVsub(1.0)% (more than 70%) in lung function tests, no abnormal findings in chest X-ray films and no symptoms and signs. The findings of aerosol inhalation scintigrams in them were classified into 3 patterns; type I: homogeneous distribution without central airway deposit, type II: homogeneous distribution with central airway deposit, type III: inhomogeneous distribution. These patterns were compared with lung function tests. There was no significant correlation between type I and type II in lung function tests. Type III was different from type I and type II in inhomogeneous distribution. This finding showed no correlation with %VC, FEVsub(1.0)%, MMF, V radical50 and V radical50/V radical25, but good correlation with V radical25 in a maximum forced expiratory flow-volume curve. Flow-volume curve is one of the sensitive methods in early detection of COPD, so inhomogeneous distribution of type III is considered to be due to small airway dysfunction.

Adsorption of radioactive I2 gas onto fly-ash aerosol

International Nuclear Information System (INIS)

Noguchi, Hiroshi; Murata, Mikio; Suzuki, Katsumi.

1988-01-01

The adsorption of radioactive elemental iodine (I 2 ) gas onto fly-ash aerosol has been studied to provide basic data for the realistic and precise assessment of dose to the general public from radioiodine released from nuclear facilities. A mixture of fly-ash aerosol and 131 I 2 gas was passed through a cylindrical glass vessel so that particulate iodine was formed by adsorption of I 2 onto aerosol. Then the concentrations of I 2 and particulate iodine were measured. It was found that the adsorption reached an equilibrium state between 5 and 12 min and that the proportion of iodine which was adsorbed on the aerosol decreased with increasing initial I 2 concentration ranging over 10 -13 to 10 -9 g/cm 3 . The adsorption isotherm of the aerosol for I 2 gas approximately followed Freundlich isotherm. Using the adsorption isotherm, a theoretical equation was derived to explain the adsorption on the basis of FUCHS' theory on the evaporation of droplets. A sticking probability in the equation decreased with increasing adsorbed amount. The calculated results were in good agreement with the experimental ones. (author)

Aerosol Hygroscopicity Distribution and Mixing State Determined by Cloud Condensation Nuclei (CCN) Measurements

Science.gov (United States)

Su, H.; Rose, D.; Cheng, Y.; Gunthe, S. S.; Wiedensohler, A.; Andreae, M. O.; Pöschl, U.

2009-12-01

This paper presents, firstly the concept of hygroscopicity distribution and its application in the analysis of cloud condensation nuclei (CCN) measurement data. The cumulative particle hygroscopicity distribution function N(κ) is defined as the number concentration of particles with a hygroscopicity parameter, κ, smaller than a certain value of κ. Since the measured CCN (at supersaturation S) can be considered as those particles with κ larger than a certain value, the CCN efficiency spectra (activation curve) can be easily converted to N(κ) distributions. Unlike studies calculating only one hygroscopicity parameter from a CCN activation curve, the concept of N(κ) shows the usefulness of all points on the activation curve. Modeling studies of three assumed N(κ) distributions are used to illustrate the new concept N(κ) and how it is related to the size-resolved CCN measurements. Secondly, we discuss the aerosol mixing state information that can be obtained from the shape of N(κ). A case study is performed based on the CCN measurements during the CAREBEIJING 2006 campaign. In the campaign-averaged N(κ) distribution, most particles (>80%) lie in a mode with a geometric mean κ around 0.2-0.4, and an increasing trend in the mean κ is found as particle size increases. There seems to be another less hygroscopic mode but the κ resolution (depending on the size resolution) in the campaign is not high enough to interpret it. It is also clear that N(κ) is not a monodisperse distribution (implying an internal mixture of the aerosols). The dispersion parameter σg,κ, which is the geometric standard deviation of N(κ), can be used as an indicator for the aerosol mixing state. The indicator σg,κ shows good agreement with the soot mixing state measured by a volatility tandem differential mobility analyzer (VTDMA) during the CAREBEIJING 2006 campaign. The concept of N(κ) can be widely used to study aerosol mixing states, especially in the lab experiment where a

Commissioning of the Winfrith Aerosol Deposition and Pipe Flow Facility (ADPFF)

International Nuclear Information System (INIS)

Ball, M.H.E.; Mitchell, J.P.; Brighton, F.R.

1991-02-01

A facility has been constructed to investigate the turbulent deposition behaviour of micron-sized particles in large pipes. These studies are designed to generate suitable data to test and develop the ATLAS code, being developed by the AEA Safety and Reliability Business, to model aerosol transport through reactor components in certain severe accident sequences. The design specification of the Aerosol Deposition and Pipe Flow Facility (ADPFF) is described, together with the basic control instrumentation and commissioning trials. A preliminary assessment of the air velocity profiles measured at a Reynolds number of 10 5 is also included. The ADPFF meets the design specification and is available for the start of the first series of experiments to study aerosol deposition behaviour. (author)

A New Paradigm for Diagnosing Contributions to Model Aerosol Forcing Error

Science.gov (United States)

Jones, A. L.; Feldman, D. R.; Freidenreich, S.; Paynter, D.; Ramaswamy, V.; Collins, W. D.; Pincus, R.

2017-12-01

A new paradigm in benchmark absorption-scattering radiative transfer is presented that enables both the globally averaged and spatially resolved testing of climate model radiation parameterizations in order to uncover persistent sources of biases in the aerosol instantaneous radiative effect (IRE). A proof of concept is demonstrated with the Geophysical Fluid Dynamics Laboratory AM4 and Community Earth System Model 1.2.2 climate models. Instead of prescribing atmospheric conditions and aerosols, as in prior intercomparisons, native snapshots of the atmospheric state and aerosol optical properties from the participating models are used as inputs to an accurate radiation solver to uncover model-relevant biases. These diagnostic results show that the models' aerosol IRE bias is of the same magnitude as the persistent range cited ( 1 W/m2) and also varies spatially and with intrinsic aerosol optical properties. The findings underscore the significance of native model error analysis and its dispositive ability to diagnose global biases, confirming its fundamental value for the Radiative Forcing Model Intercomparison Project.

Basic Concepts and Principles of Marketing.

Science.gov (United States)

Beder, Hal

1986-01-01

Presents an overview of marketing concepts and principles. These include (1) organizational objectives, (2) exchange, (3) value, (4) market segmentation, (5) market position, (6) consumer analysis, (7) product, (8) promotion, (9) place, and (10) price. (CH)

Organic aerosols

International Nuclear Information System (INIS)

Penner, J.E.

1994-01-01

Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN

Parametric study of sodium aerosols in the cover-gas space of sodium-cooled reactors

International Nuclear Information System (INIS)

Sheth, A.

1975-03-01

A mathematical model has been developed to describe the behavior of sodium aerosols in the cover-gas space of a sodium-cooled reactor. A review of the literature was first made to examine methods of aerosol generation, mathematical expressions representing aerosol behavior, and pertinent experimental investigations of sodium aerosols. In the development of the model, some terms were derived from basic principles and other terms were estimated from available correlations. The model was simulated on a computer, and important parameters were studied to determine their effects on the overall behavior of sodium aerosols. The parameters studied were sodium pool temperature, source and initial size of particles, film thickness at the sodium pool/cover gas interface, wall plating parameters, cover-gas flow rate, and type of cover gas (argon and helium). The model satisfactorily describes the behavior of sodium aerosol in argon, but not in helium. Possible reasons are given for the failure of the model with helium, and further experimental work is recommended. The mathematical model, with appropriate modifications to describe the behavior of sodium aerosols in helium, would be very useful in designing traps to remove aerosols from the cover gas of sodium-cooled reactors. (U.S.)

Research on aerosol formation, aerosol behaviour, aerosol filtration, aerosol measurement techniques and sodium fires at the Laboratory for Aerosol Physics and Filter Technology at the Nuclear Research Center Karlsruhe

Energy Technology Data Exchange (ETDEWEB)

Jordan, S; Schikarski, W; Schoeck, W [Gesellschaft fuer Kernforschung mbH, Karlsruhe (Germany)

1977-01-01

The behaviour of aerosols in LMFBR plant systems is of great importance for a number of problems, both normal operational and accident kind. This paper covers the following: aerosol modelling for LMFBR containment systems; aerosol size spectrometry by laser light scattering; experimental facilities and experimental results concerned with aerosol release under accident conditions; filtration of sodium oxide aerosols by multilayer sand bed filters.

Research on aerosol formation, aerosol behaviour, aerosol filtration, aerosol measurement techniques and sodium fires at the Laboratory for Aerosol Physics and Filter Technology at the Nuclear Research Center Karlsruhe

International Nuclear Information System (INIS)

Jordan, S.; Schikarski, W.; Schoeck, W.

1977-01-01

The behaviour of aerosols in LMFBR plant systems is of great importance for a number of problems, both normal operational and accident kind. This paper covers the following: aerosol modelling for LMFBR containment systems; aerosol size spectrometry by laser light scattering; experimental facilities and experimental results concerned with aerosol release under accident conditions; filtration of sodium oxide aerosols by multilayer sand bed filters

Aerosol-type retrieval and uncertainty quantification from OMI data

Science.gov (United States)

Kauppi, Anu; Kolmonen, Pekka; Laine, Marko; Tamminen, Johanna

2017-11-01

We discuss uncertainty quantification for aerosol-type selection in satellite-based atmospheric aerosol retrieval. The retrieval procedure uses precalculated aerosol microphysical models stored in look-up tables (LUTs) and top-of-atmosphere (TOA) spectral reflectance measurements to solve the aerosol characteristics. The forward model approximations cause systematic differences between the modelled and observed reflectance. Acknowledging this model discrepancy as a source of uncertainty allows us to produce more realistic uncertainty estimates and assists the selection of the most appropriate LUTs for each individual retrieval.This paper focuses on the aerosol microphysical model selection and characterisation of uncertainty in the retrieved aerosol type and aerosol optical depth (AOD). The concept of model evidence is used as a tool for model comparison. The method is based on Bayesian inference approach, in which all uncertainties are described as a posterior probability distribution. When there is no single best-matching aerosol microphysical model, we use a statistical technique based on Bayesian model averaging to combine AOD posterior probability densities of the best-fitting models to obtain an averaged AOD estimate. We also determine the shared evidence of the best-matching models of a certain main aerosol type in order to quantify how plausible it is that it represents the underlying atmospheric aerosol conditions.The developed method is applied to Ozone Monitoring Instrument (OMI) measurements using a multiwavelength approach for retrieving the aerosol type and AOD estimate with uncertainty quantification for cloud-free over-land pixels. Several larger pixel set areas were studied in order to investigate the robustness of the developed method. We evaluated the retrieved AOD by comparison with ground-based measurements at example sites. We found that the uncertainty of AOD expressed by posterior probability distribution reflects the difficulty in model

Aerosol-type retrieval and uncertainty quantification from OMI data

Directory of Open Access Journals (Sweden)

A. Kauppi

2017-11-01

Full Text Available We discuss uncertainty quantification for aerosol-type selection in satellite-based atmospheric aerosol retrieval. The retrieval procedure uses precalculated aerosol microphysical models stored in look-up tables (LUTs and top-of-atmosphere (TOA spectral reflectance measurements to solve the aerosol characteristics. The forward model approximations cause systematic differences between the modelled and observed reflectance. Acknowledging this model discrepancy as a source of uncertainty allows us to produce more realistic uncertainty estimates and assists the selection of the most appropriate LUTs for each individual retrieval.This paper focuses on the aerosol microphysical model selection and characterisation of uncertainty in the retrieved aerosol type and aerosol optical depth (AOD. The concept of model evidence is used as a tool for model comparison. The method is based on Bayesian inference approach, in which all uncertainties are described as a posterior probability distribution. When there is no single best-matching aerosol microphysical model, we use a statistical technique based on Bayesian model averaging to combine AOD posterior probability densities of the best-fitting models to obtain an averaged AOD estimate. We also determine the shared evidence of the best-matching models of a certain main aerosol type in order to quantify how plausible it is that it represents the underlying atmospheric aerosol conditions.The developed method is applied to Ozone Monitoring Instrument (OMI measurements using a multiwavelength approach for retrieving the aerosol type and AOD estimate with uncertainty quantification for cloud-free over-land pixels. Several larger pixel set areas were studied in order to investigate the robustness of the developed method. We evaluated the retrieved AOD by comparison with ground-based measurements at example sites. We found that the uncertainty of AOD expressed by posterior probability distribution reflects the

Basic conceptions for development of new-type high-efficiency cooling towers with enhanced reliability, maneuverability and maintainability

International Nuclear Information System (INIS)

Kim En Be; Nedviga, Yu.S.

1990-01-01

The state-of-the-art of cooling tower design, construction and operation is analysed. From the analysis formulated are general requirements which can be imposed upon cooling towers serving as most important technological apparatuses in water supply systems of thermal and nuclear power plants. With these requirements taken into account, basic research and technical conceptions are developed to be used in designing new-type cooling towers characterized by enhanced reliability, maneuverability and maintainability

Measuring student teachers' basic psychological needs

NARCIS (Netherlands)

dr Bob Koster; Dr. Jos Castelijns; Dr. Marjan Vermeulen; dr.ir. Quinta Kools

2012-01-01

In the Self-Determination Theory (SDT) basic psychological needs for relatedness, autonomy and competence are distinguished. Basic psychological need fulfilment is considered to be critical for human development and intrinsic motivation. In the Netherlands, the concept of basic psychological need

Measuring student teachers’ basic psychological needs

NARCIS (Netherlands)

Vermeulen, Marjan; Castelijns, Jos; Koster, Bob; Kools, Quinta

2018-01-01

In the Self–Determination Theory (SDT) basic psychological needs for relatedness, autonomy and competence are distinguished. Basic psychological need fulfilment is considered to be critical for human development and intrinsic motivation. In the Netherlands, the concept of basic psychological need

Calibration of aerosol radiometers. Special aerosol sources

International Nuclear Information System (INIS)

Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

1988-01-01

Problems of calibration of artificial aerosol radiometry and information-measurement systems of radiometer radiation control, in particular, are considered. Special aerosol source is suggested, which permits to perform certification and testing of aerosol channels of the systems in situ without the dismantling

Basic conception of simultaneous multi-layer hybrid type ECT apparatus 'HEADTOME-2'

International Nuclear Information System (INIS)

Nakanishi, Shigemasa

1981-01-01

Following on the one-slice hybrid type ECT (emission computer tomography) apparatus HEADTOME-1 for the measurement of local cerebral blood stream by single-photon measurement and the measurement of local cerebral metabolism by positron measurement, the development of the simultaneous multi-layer hybrid type ECT apparatus HEADTOME-2 was started for the simultaneous measurement of whole brains. Being designed also for obtaining single-photon simultaneous multi-layer tomography, a peculiar mode of collimator structure was employed, thereby the defect in HEADTOME-1 was eliminated. The design of the detector section is as follows: detector array diameter 42 cm, effective vision-field diameter 21 cm, patient tunnel diameter 25 cm, detector rings 3, slice interval 35 cm, and NaI (Tl) crystals 64 per layer. The basic conception of HEADTOME-2, such as the detectors, collimator, the number of slices, specifications, and data processing system, is described. (J.P.N.)

The Basic Concepts of Contemporary Psychology.

Science.gov (United States)

Davydov, V. V.

1988-01-01

Presents chapter one of V. V. Davydov's 1986 monograph, "Problems of Developmental Teaching." Examines the dialectical-materialist sources of the psychological concept of activity; and activity, the mind, and consciousness. Building from Lev S. Vygotsky's work and within a Marxist-Leninist framework, explores relationships among…

TEM investigations of microstructures of combustion aerosols

International Nuclear Information System (INIS)

Marquardt, A.; Hackfort, H.; Borchardt, J.; Schober, T.; Friedrich, J.

1992-12-01

In the incineration of organic material, apart from a series of gaseous pollutants, particulate pollutants or combustion aerosols also arise. The latter frequently consist of particles with a solid core of carbon to which a large number of inorganic and organic compounds are attached. These primarily include the polycyclic aromatic hydrocarbons (PAH) and their nitro-derivatives (NPAH), whose mutagenic or carcinogenic effect is known. The invisible particle sizes in the nanometer range, whose retention in the incineration off-gas is not state of the art, are of increasing significance for man and environment. On the one hand, they are deposited almost completely in the human lung. On the other hand, due to their fine dispersity they have along residence time in the atmosphere where they participate in chemical reactions and climatically significant processes. Important insights about the formation process of combustion aerosols are to be expected from the imaging of their microstructures in the transmission electron microscope (TEM). The present contribution describes the development and application of a representative sampling procedure for aerosols from a partial flow of flue gas from a fluidized-bed furnace. The method developed consists of electrically charging aerosol particles in situ and subsequently selectively precipitating them onto a microscope slide in an electric field. TEM studies of aerosol microstructures on the microscope slides revealed that in the combustion of petrol and heating oil under different combustion conditions in principle the same particle structures result, whereas in the incineration of used lubricating oil quite different particle structures were found. Results from the literature on aerosol microstructures in exhaust gases from petrol and diesel engines demonstrate agreement with the results of this study in the basic structure of the particles. (orig.) [de

Probing functional groups at the gas-aerosol interface using heterogeneous titration reactions: a tool for predicting aerosol health effects?

Science.gov (United States)

Setyan, Ari; Sauvain, Jean-Jacques; Guillemin, Michel; Riediker, Michael; Demirdjian, Benjamin; Rossi, Michel J

2010-12-17

The complex chemical and physical nature of combustion and secondary organic aerosols (SOAs) in general precludes the complete characterization of both bulk and interfacial components. The bulk composition reveals the history of the growth process and therefore the source region, whereas the interface controls--to a large extent--the interaction with gases, biological membranes, and solid supports. We summarize the development of a soft interrogation technique, using heterogeneous chemistry, for the interfacial functional groups of selected probe gases [N(CH(3))(3), NH(2)OH, CF(3)COOH, HCl, O(3), NO(2)] of different reactivity. The technique reveals the identity and density of surface functional groups. Examples include acidic and basic sites, olefinic and polycyclic aromatic hydrocarbon (PAH) sites, and partially and completely oxidized surface sites. We report on the surface composition and oxidation states of laboratory-generated aerosols and of aerosols sampled in several bus depots. In the latter case, the biomarker 8-hydroxy-2'-deoxyguanosine, signaling oxidative stress caused by aerosol exposure, was isolated. The increase in biomarker levels over a working day is correlated with the surface density N(i)(O3) of olefinic and/or PAH sites obtained from O(3) uptakes as well as with the initial uptake coefficient, γ(0), of five probe gases used in the field. This correlation with γ(0) suggests the idea of competing pathways occurring at the interface of the aerosol particles between the generation of reactive oxygen species (ROS) responsible for oxidative stress and cellular antioxidants.

Using the OMI aerosol index and absorption aerosol optical depth to evaluate the NASA MERRA Aerosol Reanalysis

Science.gov (United States)

Buchard, V.; da Silva, A. M.; Colarco, P. R.; Darmenov, A.; Randles, C. A.; Govindaraju, R.; Torres, O.; Campbell, J.; Spurr, R.

2015-05-01

A radiative transfer interface has been developed to simulate the UV aerosol index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) aerosol assimilated fields. The purpose of this work is to use the AI and aerosol absorption optical depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications Aerosol Reanalysis (MERRAero). MERRAero is based on a version of the GEOS-5 model that is radiatively coupled to the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) aerosol module and includes assimilation of aerosol optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Since AI is dependent on aerosol concentration, optical properties and altitude of the aerosol layer, we make use of complementary observations to fully diagnose the model, including AOD from the Multi-angle Imaging SpectroRadiometer (MISR), aerosol retrievals from the AErosol RObotic NETwork (AERONET) and attenuated backscatter coefficients from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) mission to ascertain potential misplacement of plume height by the model. By sampling dust, biomass burning and pollution events in 2007 we have compared model-produced AI and AAOD with the corresponding OMI products, identifying regions where the model representation of absorbing aerosols was deficient. As a result of this study over the Saharan dust region, we have obtained a new set of dust aerosol optical properties that retains consistency with the MODIS AOD data that were assimilated, while resulting in better agreement with aerosol absorption measurements from OMI. The analysis conducted over the southern African and South American biomass burning regions indicates that revising the spectrally dependent aerosol absorption properties in the near-UV region improves the modeled-observed AI comparisons

Basic concepts of control theory

International Nuclear Information System (INIS)

Markus, L.

1976-01-01

After a philosophical introduction on control theory and its position among various branches of science, mathematical control theory and its connection with functional analysis are discussed. A chapter on system theory concepts follows. After a summary of results and notations in the general theory of ordinary differential equations, a qualitative theory of control dynamical systems and chapters on the topological dynamics, and the controllability of linear systems are presented. As examples of autonomous linear systems, the switching locus for the synthesis of optimal controllers and linear dynamics with quadratic cost optimization are considered. (author)

Basic concepts of string theory

International Nuclear Information System (INIS)

Blumenhagen, Ralph

2013-01-01

The purpose of this book is to thoroughly prepare the reader for research in string theory. It is intended as a textbook in the sense that, starting from the basics, the material is presented in a pedagogical and self-contained fashion. The emphasis is on the world-sheet perspective of closed strings and of open strings ending on D-branes, where two-dimensional conformal field theory is the main tool. Compactifications of string theory, with and without fluxes, and string dualities are also discussed from the space-time point of view, i.e. in geometric language. End-of-chapter references have been added to guide the reader intending to pursue further studies or to start research in the topics covered by this book.

Concept Systems and Ontologies: Recommendations for Basic Terminology

Science.gov (United States)

Klein, Gunnar O.; Smith, Barry

This essay concerns the problems surrounding the use of the term ``concept'' in current ontology and terminology research. It is based on the constructive dialogue between realist ontology on the one hand and the world of formal standardization of health informatics on the other, but its conclusions are not restricted to the domain of medicine. The term ``concept'' is one of the most misused even in literature and technical standards which attempt to bring clarity. In this paper we propose to use the term ``concept'' in the context of producing defined professional terminologies with one specific and consistent meaning which we propose for adoption as the agreed meaning of the term in future terminological research, and specifically in the development of formal terminologies to be used in computer systems. We also discuss and propose new definitions of a set of cognate terms. We describe the relations governing the realm of concepts, and compare these to the richer and more complex set of relations obtaining between entities in the real world. On this basis we also summarize an associated terminology for ontologies as representations of the real world and a partial mapping between the world of concepts and the world of reality.

Aerosol behaviour modeling and measurements

Energy Technology Data Exchange (ETDEWEB)

Gieseke, J A; Reed, L D [Batelle Memorial Institute, Columbus, OH (United States)

1977-01-01

Aerosol behavior within Liquid Metal Fast Breeder Reactor (LMFBR) containments is of critical importance since most of the radioactive species are expected to be associated with particulate forms and the mass of radiologically significant material leaked to the ambient atmosphere is directly related to the aerosol concentration airborne within the containment. Mathematical models describing the behavior of aerosols in closed environments, besides providing a direct means of assessing the importance of specific assumptions regarding accident sequences, will also serve as the basic tool with which to predict the consequences of various postulated accident situations. Consequently, considerable efforts have been recently directed toward the development of accurate and physically realistic theoretical aerosol behavior models. These models have accounted for various mechanisms affecting agglomeration rates of airborne particulate matter as well as particle removal rates from closed systems. In all cases, spatial variations within containments have been neglected and a well-mixed control volume has been assumed. Examples of existing computer codes formulated from the mathematical aerosol behavior models are the Brookhaven National Laboratory TRAP code, the PARDISEKO-II and PARDISEKO-III codes developed at Karlsruhe Nuclear Research Center, and the HAA-2, HAA-3, and HAA-3B codes developed by Atomics International. Because of their attractive short computation times, the HAA-3 and HAA-3B codes have been used extensively for safety analyses and are attractive candidates with which to demonstrate order of magnitude estimates of the effects of various physical assumptions. Therefore, the HAA-3B code was used as the nucleus upon which changes have been made to account for various physical mechanisms which are expected to be present in postulated accident situations and the latest of the resulting codes has been termed the HAARM-2 code. It is the primary purpose of the HAARM

Basic stress analysis

CERN Document Server

Iremonger, M J

1982-01-01

BASIC Stress Analysis aims to help students to become proficient at BASIC programming by actually using it in an important engineering subject. It also enables the student to use computing as a means of learning stress analysis because writing a program is analogous to teaching-it is necessary to understand the subject matter. The book begins by introducing the BASIC approach and the concept of stress analysis at first- and second-year undergraduate level. Subsequent chapters contain a summary of relevant theory, worked examples containing computer programs, and a set of problems. Topics c

Relative importance of nitrate and sulfate aerosol production mechanisms in urban atmospheres

International Nuclear Information System (INIS)

Middleton, P.; Kiang, C.S.

1979-01-01

The relative importance of the various sulfate and nitrate aerosol production mechanisms is calculated for different atmospheric conditions. The calculation scheme used to determine the rates of nitrate and sulfate production, based on the concept that vapor transfer to the aerosols and nitrate and sulfate formation within the aerosols are coupled kinetic processes, considers sulfate formation by ozone and hydrogen peroxide oxidation and catalytic oxidation in the presence of soot, iron and manganese of sulfite solutions and sulfuric acid condensation and nitrate formation by the liquid-phase oxidation of dissolved nitrogen oxides for different initial gas concentrations and particle compositions and sizes. It is found that sulfate production is higher under daytime conditions, primarily proceeding by mechanisms involving sulfuric acid and hydrogen peroxide, while at night oxidation processes on the surface of the aerosol film are more important. Nitrate tends to decrease nighttime sulfate production due to an increase in aerosol acidity and nitrate production is found to be higher under nighttime conditions and in the winter

Gravitational agglomeration of post-HCDA LMFBR aerosols: nonspherical particles

International Nuclear Information System (INIS)

Tuttle, R.F.; Loyalka, S.K.

1982-12-01

Aerosol behavior analysis computer programs have shown that temporal aerosol size distributions in nuclear reactor containments are sensitive to shape factors. This research investigates shape factors by a detailed theoretical analysis of hydrodynamic interactions between a nonspherical particle and a spherical particle undergoing gravitational collisions in an LMFBR environment. First, basic definitions and expressions for settling speeds and collisional efficiencies of nonspherical particles are developed. These are then related to corresponding quantities for spherical particles through shape factors. Using volume equivalent diameter as the defining length in the gravitational collision kernel, the aerodynamic shape factor, the density correction factor, and the gravitational collision shape factor, are introduced to describe the collision kernel for collisions between aerosol agglomerates. The Navier-Stokes equation in oblate spheroidal coordinates is solved to model a nonspherical particle and then the dynamic equations for two particle motions are developed. A computer program (NGCEFF) is constructed, and the dynamical equations are solved by Gear's method

Impact of Aerosols on Convective Clouds and Precipitation

Science.gov (United States)

Tao, Wei-Kuo; Chen, Jen-Ping; Li, Zhanqing; Wang, Chien; Zhang, Chidong; Li, Xiaowen

2012-01-01

Aerosols are a critical.factor in the atmospheric hydrological cycle and radiation budget. As a major agent for clouds to form and a significant attenuator of solar radiation, aerosols affect climate in several ways. Current research suggests that aerosols have a major impact on the dynamics, microphysics, and electrification properties of continental mixed-phase convective clouds. In addition, high aerosol concentrations in urban environments could affect precipitation variability by providing a significant source of cloud condensation nuclei (CCN). Such pollution . effects on precipitation potentially have enormous climatic consequences both in terms of feedbacks involving the land surface via rainfall as well as the surface energy budget and changes in latent heat input to the atmosphere. Basically, aerosol concentrations can influence cloud droplet size distributions, the warm-rain process, the cold-rain process, cloud-top heights, the depth of the mixed-phase region, and the occurrence of lightning. Recently, many cloud resolution models (CRMs) have been used to examine the role of aerosols on mixed-phase convective clouds. These modeling studies have many differences in terms of model configuration (two- or three-dimensional), domain size, grid spacing (150-3000 m), microphysics (two-moment bulk, simple or sophisticated spectral-bin), turbulence (1st or 1.5 order turbulent kinetic energy (TKE)), radiation, lateral boundary conditions (i.e., closed, radiative open or cyclic), cases (isolated convection, tropical or midlatitude squall lines) and model integration time (e.g., 2.5 to 48 hours). Among these modeling studies, the most striking difference is that cumulative precipitation can either increase or decrease in response to higher concentrations of CCN. In this presentation, we review past efforts and summarize our current understanding of the effect of aerosols on convective precipitation processes. Specifically, this paper addresses the following topics

Improvement of the CULTEX® exposure technology by radial distribution of the test aerosol.

Science.gov (United States)

Aufderheide, Michaela; Heller, Wolf-Dieter; Krischenowski, Olaf; Möhle, Niklas; Hochrainer, Dieter

2017-07-05

The exposure of cellular based systems cultivated on microporous membranes at the air-liquid interface (ALI) has been accepted as an appropriate approach to simulate the exposure of cells of the respiratory tract to native airborne substances. The efficiency of such an exposure procedure with regard to stability and reproducibility depends on the optimal design at the interface between the cellular test system and the exposure technique. The actual exposure systems favor the dynamic guidance of the airborne substances to the surface of the cells in specially designed exposure devices. Two module types, based on a linear or radial feed of the test atmosphere to the test system, were used for these studies. In our technical history, the development started with the linear designed version, the CULTEX ® glass modules, fulfilling basic requirements for running ALI exposure studies (Mohr and Durst, 2005). The instability in the distribution of different atmospheres to the cells caused us to create a new exposure module, characterized by a stable and reproducible radial guidance of the aerosol to the cells. The outcome was the CULTEX ® RFS (Mohr et al., 2010). In this study, we describe the differences between the two systems with regard to particle distribution and deposition clarifying the advantages and disadvantages of a radial to a linear aerosol distribution concept. Copyright © 2017 Elsevier GmbH. All rights reserved.

Basic Concepts for Convection Parameterization in Weather Forecast and Climate Models: COST Action ES0905 Final Report

Directory of Open Access Journals (Sweden)

Jun–Ichi Yano

2014-12-01

Full Text Available The research network “Basic Concepts for Convection Parameterization in Weather Forecast and Climate Models” was organized with European funding (COST Action ES0905 for the period of 2010–2014. Its extensive brainstorming suggests how the subgrid-scale parameterization problem in atmospheric modeling, especially for convection, can be examined and developed from the point of view of a robust theoretical basis. Our main cautions are current emphasis on massive observational data analyses and process studies. The closure and the entrainment–detrainment problems are identified as the two highest priorities for convection parameterization under the mass–flux formulation. The need for a drastic change of the current European research culture as concerns policies and funding in order not to further deplete the visions of the European researchers focusing on those basic issues is emphasized.

Fast time-resolved aerosol collector: proof of concept

Science.gov (United States)

Yu, X.-Y.; Cowin, J. P.; Iedema, M. J.; Ali, H.

2010-10-01

Atmospheric particles can be collected in the field on substrates for subsequent laboratory analysis via chemically sensitive single particle methods such as scanning electron microscopy with energy dispersive x-ray analysis. With moving substrates time resolution of seconds to minutes can be achieved. In this paper, we demonstrate how to increase the time resolution when collecting particles on a substrate to a few milliseconds to provide real-time information. Our fast time-resolved aerosol collector ("Fast-TRAC") microscopically observes the particle collection on a substrate and records an on-line video. Particle arrivals are resolved to within a single frame (4-17 ms in this setup), and the spatial locations are matched to the subsequent single particle analysis. This approach also provides in-situ information on particle size and number concentration. Applications are expected in airborne studies of cloud microstructure, pollution plumes, and surface long-term monitoring.

Health recommender systems: concepts, requirements, technical basics and challenges.

Science.gov (United States)

Wiesner, Martin; Pfeifer, Daniel

2014-03-03

During the last decades huge amounts of data have been collected in clinical databases representing patients' health states (e.g., as laboratory results, treatment plans, medical reports). Hence, digital information available for patient-oriented decision making has increased drastically but is often scattered across different sites. As as solution, personal health record systems (PHRS) are meant to centralize an individual's health data and to allow access for the owner as well as for authorized health professionals. Yet, expert-oriented language, complex interrelations of medical facts and information overload in general pose major obstacles for patients to understand their own record and to draw adequate conclusions. In this context, recommender systems may supply patients with additional laymen-friendly information helping to better comprehend their health status as represented by their record. However, such systems must be adapted to cope with the specific requirements in the health domain in order to deliver highly relevant information for patients. They are referred to as health recommender systems (HRS). In this article we give an introduction to health recommender systems and explain why they are a useful enhancement to PHR solutions. Basic concepts and scenarios are discussed and a first implementation is presented. In addition, we outline an evaluation approach for such a system, which is supported by medical experts. The construction of a test collection for case-related recommendations is described. Finally, challenges and open issues are discussed.

Health Recommender Systems: Concepts, Requirements, Technical Basics and Challenges

Directory of Open Access Journals (Sweden)

Martin Wiesner

2014-03-01

Full Text Available During the last decades huge amounts of data have been collected in clinical databases representing patients’ health states (e.g., as laboratory results, treatment plans, medical reports. Hence, digital information available for patient-oriented decision making has increased drastically but is often scattered across different sites. As as solution, personal health record systems (PHRS are meant to centralize an individual’s health data and to allow access for the owner as well as for authorized health professionals. Yet, expert-oriented language, complex interrelations of medical facts and information overload in general pose major obstacles for patients to understand their own record and to draw adequate conclusions. In this context, recommender systems may supply patients with additional laymen-friendly information helping to better comprehend their health status as represented by their record. However, such systems must be adapted to cope with the specific requirements in the health domain in order to deliver highly relevant information for patients. They are referred to as health recommender systems (HRS. In this article we give an introduction to health recommender systems and explain why they are a useful enhancement to PHR solutions. Basic concepts and scenarios are discussed and a first implementation is presented. In addition, we outline an evaluation approach for such a system, which is supported by medical experts. The construction of a test collection for case-related recommendations is described. Finally, challenges and open issues are discussed.

Basic Concepts of String Theory

CERN Document Server

Blumenhagen, Ralph; Theisen, Stefan

2013-01-01

The purpose of this book is to thoroughly prepare the reader for research in string theory. It is intended as a textbook in the sense that, starting from the basics, the material is presented in a pedagogical and self-contained fashion. The emphasis is on the world-sheet perspective of closed strings and of open strings ending on D-branes, where two-dimensional conformal field theory is the main tool. Compactifications of string theory, with and without fluxes, and string dualities are also discussed from the space-time point of view, i.e. in geometric language. End-of-chapter references have been added to guide the reader intending to pursue further studies or to start research in the topics covered by this book.

Transfer of polarized light in planetary atmospheres basic concepts and practical methods

CERN Document Server

Hovenier, Joop W; Domke, Helmut

2004-01-01

The principal elements of the theory of polarized light transfer in planetary atmospheres are expounded in a systematic but concise way. Basic concepts and practical methods are emphasized, both for single and multiple scattering of electromagnetic radiation by molecules and particles in the atmospheres of planets in the Solar System, including the Earth, and beyond. A large part of the book is also useful for studies of light scattering by particles in comets, the interplanetary and interstellar medium, circumstellar disks, reflection nebulae, water bodies like oceans and suspensions of particles in a gas or liquid in the laboratory. Throughout the book symmetry principles, such as the reciprocity principle and the mirror symmetry principle, are employed. In this way the theory is made more transparent and easier to understand than in most papers on the subject. In addition, significant computational reductions, resulting from symmetry principles, are presented. Hundreds of references to relevant literature ...

SEOM's Sentinel-3/OLCI' project CAWA: advanced GRASP aerosol retrieval

Science.gov (United States)

Dubovik, Oleg; litvinov, Pavel; Huang, Xin; Aspetsberger, Michael; Fuertes, David; Brockmann, Carsten; Fischer, Jürgen; Bojkov, Bojan

2016-04-01

The CAWA "Advanced Clouds, Aerosols and WAter vapour products for Sentinel-3/OLCI" ESA-SEOM project aims on the development of advanced atmospheric retrieval algorithms for the Sentinel-3/OLCI mission, and is prepared using Envisat/MERIS and Aqua/MODIS datasets. This presentation discusses mainly CAWA aerosol product developments and results. CAWA aerosol retrieval uses recently developed GRASP algorithm (Generalized Retrieval of Aerosol and Surface Properties) algorithm described by Dubovik et al. (2014). GRASP derives extended set of atmospheric parameters using multi-pixel concept - a simultaneous fitting of a large group of pixels under additional a priori constraints limiting the time variability of surface properties and spatial variability of aerosol properties. Over land GRASP simultaneously retrieves properties of both aerosol and underlying surface even over bright surfaces. GRAPS doesn't use traditional look-up-tables and performs retrieval as search in continuous space of solution. All radiative transfer calculations are performed as part of the retrieval. The results of comprehensive sensitivity tests, as well as results obtained from real Envisat/MERIS data will be presented. The tests analyze various aspects of aerosol and surface reflectance retrieval accuracy. In addition, the possibilities of retrieval improvement by means of implementing synergetic inversion of a combination of OLCI data with observations by SLSTR are explored. Both the results of numerical tests, as well as the results of processing several years of Envisat/MERIS data illustrate demonstrate reliable retrieval of AOD (Aerosol Optical Depth) and surface BRDF. Observed retrieval issues and advancements will be discussed. For example, for some situations we illustrate possibilities of retrieving aerosol absorption - property that hardly accessible from satellite observations with no multi-angular and polarimetric capabilities.

Physical metrology of aerosols; Metrologie physique des aerosols

Energy Technology Data Exchange (ETDEWEB)

Boulaud, D.; Vendel, J. [CEA Saclay, 91 - Gif-sur-Yvette (France). Inst. de Protection et de Surete Nucleaire

1996-12-31

The various detection and measuring methods for aerosols are presented, and their selection is related to aerosol characteristics (size range, concentration or mass range), thermo-hydraulic conditions (carrier fluid temperature, pressure and flow rate) and to the measuring system conditions (measuring frequency, data collection speed, cost...). Methods based on aerosol dynamic properties (inertial, diffusional and electrical methods) and aerosol optical properties (localized and integral methods) are described and their performances and applications are compared

The Effect of Aerosol Hygroscopicity and Volatility on Aerosol Optical Properties During Southern Oxidant and Aerosol Study

Science.gov (United States)

Khlystov, A.; Grieshop, A. P.; Saha, P.; Subramanian, R.

2014-12-01

Secondary organic aerosol (SOA) from biogenic sources can influence optical properties of ambient aerosol by altering its hygroscopicity and contributing to light absorption directly via formation of brown carbon and indirectly by enhancing light absorption by black carbon ("lensing effect"). The magnitude of these effects remains highly uncertain. A set of state-of-the-art instruments was deployed at the SEARCH site near Centerville, AL during the Southern Oxidant and Aerosol Study (SOAS) campaign in summer 2013 to measure the effect of relative humidity and temperature on aerosol size distribution, composition and optical properties. Light scattering and absorption by temperature- and humidity-conditioned aerosols was measured using three photo-acoustic extinctiometers (PAX) at three wavelengths (405 nm, 532 nm, and 870 nm). The sample-conditioning system provided measurements at ambient RH, 10%RH ("dry"), 85%RH ("wet"), and 200 C ("TD"). In parallel to these measurements, a long residence time temperature-stepping thermodenuder (TD) and a variable residence time constant temperature TD in combination with three SMPS systems and an Aerosol Chemical Speciation Monitor (ACSM) were used to assess aerosol volatility and kinetics of aerosol evaporation. We will present results of the on-going analysis of the collected data set. We will show that both temperature and relative humidity have a strong effect on aerosol optical properties. SOA appears to increase aerosol light absorption by about 10%. TD measurements suggest that aerosol equilibrated fairly quickly, within 2 s. Evaporation varied substantially with ambient aerosol loading and composition and meteorology.

Visualization: A Tool for Enhancing Students' Concept Images of Basic Object-Oriented Concepts

Science.gov (United States)

Cetin, Ibrahim

2013-01-01

The purpose of this study was twofold: to investigate students' concept images about class, object, and their relationship and to help them enhance their learning of these notions with a visualization tool. Fifty-six second-year university students participated in the study. To investigate his/her concept images, the researcher developed a survey…

Stratospheric aerosols

International Nuclear Information System (INIS)

Rosen, J.; Ivanov, V.A.

1993-01-01

Stratospheric aerosol measurements can provide both spatial and temporal data of sufficient resolution to be of use in climate models. Relatively recent results from a wide range of instrument techniques for measuring stratospheric aerosol parameters are described. Such techniques include impactor sampling, lidar system sensing, filter sampling, photoelectric particle counting, satellite extinction-sensing using the sun as a source, and optical depth probing, at sites mainly removed from tropospheric aerosol sources. Some of these techniques have also had correlative and intercomparison studies. The main methods for determining the vertical profiles of stratospheric aerosols are outlined: lidar extinction measurements from satellites; impactor measurements from balloons and aircraft; and photoelectric particle counter measurements from balloons, aircraft, and rockets. The conversion of the lidar backscatter to stratospheric aerosol mass loading is referred to. Absolute measurements of total solar extinction from satellite orbits can be used to extract the aerosol extinction, and several examples of vertical profiles of extinction obtained with the SAGE satellite are given. Stratospheric mass loading can be inferred from extinction using approximate linear relationships but under restrictive conditions. Impactor sampling is essentially the only method in which the physical nature of the stratospheric aerosol is observed visually. Vertical profiles of stratospheric aerosol number concentration using impactor data are presented. Typical profiles using a dual-size-range photoelectric dustsonde particle counter are given for volcanically disturbed and inactive periods. Some measurements of the global distribution of stratospheric aerosols are also presented. Volatility measurements are described, indicating that stratospheric aerosols are composed primarily of about 75% sulfuric acid and 25% water

Behavior of aerosols undergoing Brownian coagulation, Brownian diffusion and gravitational settling in a closed chamber

International Nuclear Information System (INIS)

Okuyama, Kikuo; Kousaka, Yasuo; Yoshida, Tetsuo

1976-01-01

The behavior of aerosols undergoing Brownian coagulation. Brownian diffusion and gravitational settling in a closed chamber was studied by solving the basic equation, the so-called population balance equation, numerically for a polydisperse aerosol system and analytically for a monodisperse system, and then the results were examined by experiment. In solving the basic equation, two dimensionless parameters, which are determined by the initial properties of an aerosol and the chamber dimension and also characterize the relative effects of Brownian coagulation and Brownian diffusion to gravitational settling, were introduced in order to generalize the behavior under arbitrary conditions. The calculated results, the time-dependent changes in particle number concentration and particle size distribution for a polydisperse system, were presented graphically by using the above two parameters. And further using these parameters, the domains of the three controlling factors were mapped to show the extent of each effect of these factors under various conditions for a monodisperse system. Some of the calculated results were compared with the experimental results obtained by the ultramicroscopic size analysis previously developed by the authors. (auth.)

E-Basics: Online Basic Training in Program Evaluation

Science.gov (United States)

Silliman, Ben

2016-01-01

E-Basics is an online training in program evaluation concepts and skills designed for youth development professionals, especially those working in nonformal science education. Ten hours of online training in seven modules is designed to prepare participants for mentoring and applied practice, mastery, and/or team leadership in program evaluation.…

Basic concepts of epidemiology

International Nuclear Information System (INIS)

Savitz, D.A.

1984-01-01

Epidemiology can be defined simply as the science of the distribution and determinants of disease in human populations. As a descriptive tool, epidemiology can aid health care service providers, for example, in allocation of resources. In its analytic capacity, the epidemiologic approach can help identify determinants of disease through the study of human populations. Epidemiology is primarily an observational rather than experimental methodology, with corresponding strengths and limitations. Relative to other approaches for assessing disease etiology and impacts of potential health hazards, epidemiology has a rather unique role that is complementary to, but independent of, both basic biologic sciences and clinical medicine. Experimental biologic sciences such as toxicology and physiology provide critical information on biologic mechanisms of disease required for causal inference. Clinical medicine often serves as the warning system that provides etiologic clues to be pursued through systematic investigation. The advantage of the epidemiologic approach is its reliance on human field experience, that is, the real world. While laboratory experimentation is uniquely well suited to defining potential hazards, it can neither determine whether human populations have actually been affected nor quantify that effect. Building all the complexities of human behavior and external factors into a laboratory study or mathematical model is impossible. By studying the world as it exists, epidemiology examines the integrated, summarized product of the myriad factors influencing health

Basic training of nuclear power reactor personnel

International Nuclear Information System (INIS)

Palabrica, R.J.

1981-01-01

The basic training of nuclear power reactor personnel should be given very close attention since it constitutes the foundation of their knowledge of nuclear technology. Emphasis should be given on the thorough understanding of basic nuclear concepts in order to have reasonable assurance of successful assimilation by those personnel of more specialized and advanced concepts to which they will be later exposed. Basic training will also provide a means for screening to ensure that those will be sent for further spezialized training will perform well. Finally, it is during the basic training phase when nuclear reactor operators will start to acquire and develop attitudes regarding reactor operation and it is important that these be properly founded. (orig.)

X-ray analysis of aerosol samples from a therapeutic cave

Energy Technology Data Exchange (ETDEWEB)

Alfoeldy, B. E-mail: alfi@sunserv.kfki.hu; Toeroek, Sz.; Kocsonya, A.; Szokefalvi-Nagy, Z.; Balla, Md.I

2001-04-01

Cave therapy is an efficient therapeutic method to cure asthma, the exact healing effect, however, is not clarified, yet. This study is motivated by the basic assumption that aerosols do play the key role in the cave therapy. This study is based on measurements of single aerosol particles originating from a therapeutic cave of Budapest, Hungary (Szemlohegyi cave). Aerosol particles have been collected in the regions arranged for the therapeutic treatment. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition. Three particle classes have been detected based on major element concentration: alumino-silicate, quartz and calcium carbonate. Calcium ions have well-known physiological influence: anti-spastic, anti-inflammation and excretion reducing effects. Inflammation, accompanying spasm and extreme excretion production cause the smothering stigma, the so-called asthma. Therefore it could be assumed that calcium ions present in high concentration in the cave's atmosphere is the major cause of the healing effect.

X-ray analysis of aerosol samples from a therapeutic cave

International Nuclear Information System (INIS)

Alfoeldy, B.; Toeroek, Sz.; Kocsonya, A.; Szokefalvi-Nagy, Z.; Balla, Md.I.

2001-01-01

Cave therapy is an efficient therapeutic method to cure asthma, the exact healing effect, however, is not clarified, yet. This study is motivated by the basic assumption that aerosols do play the key role in the cave therapy. This study is based on measurements of single aerosol particles originating from a therapeutic cave of Budapest, Hungary (Szemlohegyi cave). Aerosol particles have been collected in the regions arranged for the therapeutic treatment. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition. Three particle classes have been detected based on major element concentration: alumino-silicate, quartz and calcium carbonate. Calcium ions have well-known physiological influence: anti-spastic, anti-inflammation and excretion reducing effects. Inflammation, accompanying spasm and extreme excretion production cause the smothering stigma, the so-called asthma. Therefore it could be assumed that calcium ions present in high concentration in the cave's atmosphere is the major cause of the healing effect

Basic Principles and Concepts for Achieving Quality

National Research Council Canada - National Science Library

Baker, Emanuel R; Fisher, Matthew J; Goethert, Wolfhart; Marino, Lisa

2007-01-01

...) developed in the early 1980s for the Department of Defense (DoD) by Baker and colleagues. The original quality concepts of the SQF are extended beyond software to include products, services, and processes...

Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the UK

Science.gov (United States)

McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

2011-05-01

Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the UK. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA observed in

Quantum electronics basic theory

CERN Document Server

Fain, V M; Sanders, J H

1969-01-01

Quantum Electronics, Volume 1: Basic Theory is a condensed and generalized description of the many research and rapid progress done on the subject. It is translated from the Russian language. The volume describes the basic theory of quantum electronics, and shows how the concepts and equations followed in quantum electronics arise from the basic principles of theoretical physics. The book then briefly discusses the interaction of an electromagnetic field with matter. The text also covers the quantum theory of relaxation process when a quantum system approaches an equilibrium state, and explai

Aerosol studies during the ESCOMPTE experiment: an overview

Science.gov (United States)

Cachier, Hélène; Aulagnier, Fabien; Sarda, Roland; Gautier, François; Masclet, Pierre; Besombes, Jean-Luc; Marchand, Nicolas; Despiau, Serge; Croci, Delphine; Mallet, Marc; Laj, Paolo; Marinoni, Angela; Deveau, Pierre-Alexandre; Roger, Jean-Claude; Putaud, Jean-Philippe; Van Dingenen, Rita; Dell'Acqua, Alessandro; Viidanoja, Jyrkki; Martins-Dos Santos, Sebastiao; Liousse, Cathy; Cousin, Frédéric; Rosset, Robert; Gardrat, Eric; Galy-Lacaux, Corinne

2005-03-01

The "Expérience sur Site pour COntraindre les Modèles de Pollution atmosphérique et de Transport d'Emissions" (ESCOMPTE) experiment took place in the Southern part of France in the Marseilles/Fos-Berre region during 6 weeks in June and July 2001. One task was to document the regional sources of atmospheric particles and to gain some insight into the aerosol transformations in the atmosphere. For this purpose, seven sites were chosen and equipped with the same basic instrumentation to obtain the chemical closure of the bulk aerosol phase and size-segregated samples. Some specific additional experiments were conducted for the speciation of the organic matter and the aerosol size distribution in number. Finally, four multiwavelength sun-photometers were also deployed during the experiment. Interestingly, in this region, three intense aerosol sources (urban, industrial and biogenic) are very active, and data show consistent results, enlightening an important background of particles over the whole ESCOMPTE domain. Notable is the overwhelming importance of the carbonaceous fraction (comprising primary and secondary particles), which is always more abundant than sulphates. Particle size studies show that, on average, more than 90% of the mean regional aerosol number is found on a size range smaller than 300 nm in diameter. The most original result is the evidence of the rapid formation of secondary aerosols occurring in the whole ESCOMPTE domain. This formation is much more important than that usually observed at these latitudes since two thirds of the particulate mass collected off source zones is estimated to be generated during atmospheric transport. On the other hand, the marine source has poor influence in the region, especially during the overlapping pollution events of Intensive Observation Periods (IOP). Preliminary results from the 0D and 3D versions of the MesoNH-aerosol model show that, with optimised gas and particle sources, the model accounts

DSMC multicomponent aerosol dynamics: Sampling algorithms and aerosol processes

Science.gov (United States)

Palaniswaamy, Geethpriya

The post-accident nuclear reactor primary and containment environments can be characterized by high temperatures and pressures, and fission products and nuclear aerosols. These aerosols evolve via natural transport processes as well as under the influence of engineered safety features. These aerosols can be hazardous and may pose risk to the public if released into the environment. Computations of their evolution, movement and distribution involve the study of various processes such as coagulation, deposition, condensation, etc., and are influenced by factors such as particle shape, charge, radioactivity and spatial inhomogeneity. These many factors make the numerical study of nuclear aerosol evolution computationally very complicated. The focus of this research is on the use of the Direct Simulation Monte Carlo (DSMC) technique to elucidate the role of various phenomena that influence the nuclear aerosol evolution. In this research, several aerosol processes such as coagulation, deposition, condensation, and source reinforcement are explored for a multi-component, aerosol dynamics problem in a spatially homogeneous medium. Among the various sampling algorithms explored the Metropolis sampling algorithm was found to be effective and fast. Several test problems and test cases are simulated using the DSMC technique. The DSMC results obtained are verified against the analytical and sectional results for appropriate test problems. Results show that the assumption of a single mean density is not appropriate due to the complicated effect of component densities on the aerosol processes. The methods developed and the insights gained will also be helpful in future research on the challenges associated with the description of fission product and aerosol releases.

Estimation of Uncertainty in Aerosol Concentration Measured by Aerosol Sampling System

Energy Technology Data Exchange (ETDEWEB)

Lee, Jong Chan; Song, Yong Jae; Jung, Woo Young; Lee, Hyun Chul; Kim, Gyu Tae; Lee, Doo Yong [FNC Technology Co., Yongin (Korea, Republic of)

2016-10-15

FNC Technology Co., Ltd has been developed test facilities for the aerosol generation, mixing, sampling and measurement under high pressure and high temperature conditions. The aerosol generation system is connected to the aerosol mixing system which injects SiO{sub 2}/ethanol mixture. In the sampling system, glass fiber membrane filter has been used to measure average mass concentration. Based on the experimental results using main carrier gas of steam and air mixture, the uncertainty estimation of the sampled aerosol concentration was performed by applying Gaussian error propagation law. FNC Technology Co., Ltd. has been developed the experimental facilities for the aerosol measurement under high pressure and high temperature. The purpose of the tests is to develop commercial test module for aerosol generation, mixing and sampling system applicable to environmental industry and safety related system in nuclear power plant. For the uncertainty calculation of aerosol concentration, the value of the sampled aerosol concentration is not measured directly, but must be calculated from other quantities. The uncertainty of the sampled aerosol concentration is a function of flow rates of air and steam, sampled mass, sampling time, condensed steam mass and its absolute errors. These variables propagate to the combination of variables in the function. Using operating parameters and its single errors from the aerosol test cases performed at FNC, the uncertainty of aerosol concentration evaluated by Gaussian error propagation law is less than 1%. The results of uncertainty estimation in the aerosol sampling system will be utilized for the system performance data.

XBAER-derived aerosol optical thickness from OLCI/Sentinel-3 observation

Science.gov (United States)

Mei, Linlu; Rozanov, Vladimir; Vountas, Marco; Burrows, John P.; Richter, Andreas

2018-02-01

A cloud identification algorithm used for cloud masking, which is based on the spatial variability of reflectances at the top of the atmosphere in visible wavelengths, has been developed for the retrieval of aerosol properties by MODIS. It is shown that the spatial pattern of cloud reflectance, as observed from space, is very different from that of aerosols. Clouds show a high spatial variability in the scale of a hundred metres to a few kilometres, whereas aerosols in general are homogeneous. The concept of spatial variability of reflectances at the top of the atmosphere is mainly applicable over the ocean, where the surface background is sufficiently homogeneous for the separation between aerosols and clouds. Aerosol retrievals require a sufficiently accurate cloud identification to be able to mask these ground scenes. However, a conservative mask will exclude strong aerosol episodes and a less conservative mask could introduce cloud contamination that biases the retrieved aerosol optical properties (e.g. aerosol optical depth and effective radii). A detailed study on the effect of cloud contamination on aerosol retrievals has been performed and parameters are established determining the threshold value for the MODIS aerosol cloud mask (3×3-STD) over the ocean. The 3×3-STD algorithm discussed in this paper is the operational cloud mask used for MODIS aerosol retrievals over the ocean.A prolonged pollution haze event occurred in the northeast part of China during the period 16-21 December 2016. To assess the impact of such events, the amounts and distribution of aerosol particles, formed in such events, need to be quantified. The newly launched Ocean Land Colour Instrument (OLCI) onboard Sentinel-3 is the successor of the MEdium Resolution Imaging Spectrometer (MERIS). It provides measurements of the radiance and reflectance at the top of the atmosphere, which can be used to retrieve the aerosol optical thickness (AOT) from synoptic to global scales. In this

Aerosol and monsoon climate interactions over Asia: AEROSOL AND MONSOON CLIMATE INTERACTIONS

Energy Technology Data Exchange (ETDEWEB)

Li, Zhanqing [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Lau, W. K. -M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Ramanathan, V. [Department of Atmospheric and Climate Sciences, University of California, San Diego California USA; Wu, G. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Ding, Y. [National Climate Center, China Meteorological Administration, Beijing China; Manoj, M. G. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Liu, J. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Qian, Y. [Pacific Northwest National Laboratory, Richland Washington USA; Li, J. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhou, T. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Fan, J. [Pacific Northwest National Laboratory, Richland Washington USA; Rosenfeld, D. [Institute of Earth Sciences, Hebrew University, Jerusalem Israel; Ming, Y. [Geophysical Fluid Dynamic Laboratory, NOAA, Princeton New Jersey USA; Wang, Y. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Huang, J. [College of Atmospheric Sciences, Lanzhou University, Lanzhou China; Wang, B. [Department of Atmospheric Sciences, University of Hawaii, Honolulu Hawaii USA; School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Xu, X. [Chinese Academy of Meteorological Sciences, Beijing China; Lee, S. -S. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Cribb, M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Zhang, F. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Yang, X. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhao, C. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Takemura, T. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Wang, K. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Xia, X. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Yin, Y. [School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Zhang, H. [National Climate Center, China Meteorological Administration, Beijing China; Guo, J. [Chinese Academy of Meteorological Sciences, Beijing China; Zhai, P. M. [Chinese Academy of Meteorological Sciences, Beijing China; Sugimoto, N. [National Institute for Environmental Studies, Tsukuba Japan; Babu, S. S. [Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram India; Brasseur, G. P. [Max Planck Institute for Meteorology, Hamburg Germany

2016-11-15

Asian monsoons and aerosols have been studied extensively which are intertwined in influencing the climate of Asia. This paper provides a comprehensive review of ample studies on Asian aerosol, monsoon and their interactions. The region is the primary source of aerosol emissions of varies species, influenced by distinct weather and climatic regimes. On continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulation. The atmospheric thermodynamic state may also be altered by the aerosol serving as cloud condensation nuclei or ice nuclei. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of numerous monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from biomass burning, and biogenic aerosols from vegetation are considered integral components of an intrinsic aerosol-monsoon climate system, subject to external forcings of global warming, anthropogenic aerosols, and land use and change. Future research on aerosol-monsoon interactions calls for an integrated approach and international collaborations based on long-term sustained observations, process measurements, and improved models, as well as using observations to constrain model simulations and projections.

El juego como alternativa para la enseñanza de conceptos básicos de salud Games as an alternative for teaching basic health concepts

Directory of Open Access Journals (Sweden)

Juan Manuel Castillo Lizardo

2001-05-01

Full Text Available Objetivos. Determinar la eficacia de una estrategia educativa basada en juegos populares para la enseñanza de conceptos básicos de salud en niños de edad escolar que asisten a la escuela. Métodos. Estudio de intervención desarrollado en la ciudad de Durango, México, en junio de 2000, en el que se incluyeron 300 niños de 9 a 11 años de edad, asignados de manera aleatoria al grupo A, que utilizó una versión modificada del juego popular mexicano Serpientes y Escaleras, en la que se incluyeron mensajes sobre conceptos básicos de salud, o al grupo B, o grupo de control. Resultados. En condiciones basales no hubo diferencias de edad, escolaridad ni sobre conceptos básicos de salud entre los niños de ambos grupos. Después de la intervención educativa la calificación sobre conceptos básicos de salud fue de 9,3 ± 0,8 para el grupo A y de 7,5 ± 1,1 para el B (P Objective. To determine, for the teaching of basic health concepts to school-age children, the effectiveness of an educational strategy based on traditional children's games. Methods. Intervention study carried out in the city of Durango, Mexico, in June 2000 with 300 children from 9 to 11 years old. The children were randomly divided into two groups. The children in Group A used a modified version of a Mexican popular game called Serpientes y Escaleras (Snakes and Ladders that included messages on basic health concepts; the children in Group B made up the control group and did not play the modified game. Results. At baseline there were no significant differences between the two groups in terms of age, grade level, or their scores on a knowledge test of basic health concepts. After the educational intervention, the health concepts test scores, out of a maximum possible of 10, were 9.3 ± 0.8 for Group A and 7.5 ± 1.1 for Group B (P < 0.001. Conclusions. Using games that include health and hygiene messages can be an alternative for teaching basic health concepts.

Diffusion-weighted imaging: basic concepts and application in cerebral stroke and head trauma

International Nuclear Information System (INIS)

Huisman, Thierry A.G.M.

2003-01-01

Diffusion-weighted imaging (DWI) of the brain represents a new imaging technique that extends imaging from depiction of neuroanatomy to the level of function and physiology. DWI measures a fundamentally different physiological parameter compared with conventional MRI. Image contrast is related to differences in the diffusion rate of water molecules rather than to changes in total tissue water. DWI can reveal pathology in cases where conventional MRI remains unremarkable. DWI has proven to be highly sensitive in the early detection of acute cerebral ischemia and seems promising in the evaluation of traumatic brain injury. DWI can differentiate between lesions with decreased and increased diffusion. In addition, full-tensor DWI can evaluate the microscopic architecture of the brain, in particular white matter tracts, by measuring the degree and spatial distribution of anisotropic diffusion within the brain. This article reviews the basic concepts of DWI and its application in cerebral ischemia and traumatic brain injury. (orig.)

Diffusion-weighted imaging: basic concepts and application in cerebral stroke and head trauma

Energy Technology Data Exchange (ETDEWEB)

Huisman, Thierry A.G.M. [Department of Radiology, Neuroradiology Section and MGH-NMR Center, Massachusetts General Hospital and Harvard Medical School, MA 02129, Boston (United States); Department of Radiology, University Children' s Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich (Switzerland)

2003-10-01

Diffusion-weighted imaging (DWI) of the brain represents a new imaging technique that extends imaging from depiction of neuroanatomy to the level of function and physiology. DWI measures a fundamentally different physiological parameter compared with conventional MRI. Image contrast is related to differences in the diffusion rate of water molecules rather than to changes in total tissue water. DWI can reveal pathology in cases where conventional MRI remains unremarkable. DWI has proven to be highly sensitive in the early detection of acute cerebral ischemia and seems promising in the evaluation of traumatic brain injury. DWI can differentiate between lesions with decreased and increased diffusion. In addition, full-tensor DWI can evaluate the microscopic architecture of the brain, in particular white matter tracts, by measuring the degree and spatial distribution of anisotropic diffusion within the brain. This article reviews the basic concepts of DWI and its application in cerebral ischemia and traumatic brain injury. (orig.)

The aerosols and the greenhouse effect; Aerosoler og klimaeffekten

Energy Technology Data Exchange (ETDEWEB)

Iversen, Trond; Kirkevaag, Alf; Seland, Oeyvind; Debernard, Jens Boldingh; Kristjansson, Jon Egill; Storelvmo, Trude

2008-07-01

The article discussed the aerosol effects on the climatic changes and points out that the climate models do not incorporate these components satisfactorily mostly due to insufficient knowledge of the aerosol pollution sources. The direct and indirect effects of aerosols are mentioned as well as the climate response (tk)

Understanding the aerosol information content in multi-spectral reflectance measurements using a synergetic retrieval algorithm

Directory of Open Access Journals (Sweden)

D. Martynenko

2010-11-01

Full Text Available An information content analysis for multi-wavelength SYNergetic AErosol Retrieval algorithm SYNAER was performed to quantify the number of independent pieces of information that can be retrieved. In particular, the capability of SYNAER to discern various aerosol types is assessed. This information content depends on the aerosol optical depth, the surface albedo spectrum and the observation geometry. The theoretical analysis is performed for a large number of scenarios with various geometries and surface albedo spectra for ocean, soil and vegetation. When the surface albedo spectrum and its accuracy is known under cloud-free conditions, reflectance measurements used in SYNAER is able to provide for 2–4° of freedom that can be attributed to retrieval parameters: aerosol optical depth, aerosol type and surface albedo.

The focus of this work is placed on an information content analysis with emphasis to the aerosol type classification. This analysis is applied to synthetic reflectance measurements for 40 predefined aerosol mixtures of different basic components, given by sea salt, mineral dust, biomass burning and diesel aerosols, water soluble and water insoluble aerosols. The range of aerosol parameters considered through the 40 mixtures covers the natural variability of tropospheric aerosols. After the information content analysis performed in Holzer-Popp et al. (2008 there was a necessity to compare derived degrees of freedom with retrieved aerosol optical depth for different aerosol types, which is the main focus of this paper.

The principle component analysis was used to determine the correspondence between degrees of freedom for signal in the retrieval and derived aerosol types. The main results of the analysis indicate correspondence between the major groups of the aerosol types, which are: water soluble aerosol, soot, mineral dust and sea salt and degrees of freedom in the algorithm and show the ability of the SYNAER to

Basic statistics an introduction with R

CERN Document Server

Raykov, Tenko

2012-01-01

Basic Statistics provides an accessible and comprehensive introduction to statistics using the free, state-of-the-art, powerful software program R. This book is designed to both introduce students to key concepts in statistics and to provide simple instructions for using R.Teaches essential concepts in statistics, assuming little background knowledge on the part of the readerIntroduces students to R with as few sub-commands as possible for ease of useProvides practical examples from the educational, behavioral, and social sciencesBasic Statistics will appeal to students and professionals acros

Optical extinction of size-controlled aerosols generated from squid chromatophore pigments

Directory of Open Access Journals (Sweden)

Sean R. Dinneen

2017-10-01

Full Text Available Nanophotonic granules populate the interior of cephalopod chromatophores, contributing to their visible color by selectively absorbing and scattering light. Inspired by the performance of these granules, we fabricated nanostructured aerosols by nebulizing a pigment solution extracted from native squid chromatophores. We determined their optical extinction using cavity ring-down spectroscopy and show how extinction cross section is dependent on both particle concentration and size. This work not only advances the fundamental knowledge of the optical properties of chromatophore pigments but also serves as a proof-of-concept method that can be adapted to develop coatings derived from these pigmentary aerosols.

RF engineering basic concepts: S-parameters

CERN Document Server

Caspers, F

2011-01-01

The concept of describing RF circuits in terms of waves is discussed and the S-matrix and related matrices are defined. The signal flow graph (SFG) is introduced as a graphical means to visualize how waves propagate in an RF network. The properties of the most relevant passive RF devices (hybrids, couplers, non-reciprocal elements, etc.) are delineated and the corresponding S-parameters are given. For microwave integrated circuits (MICs) planar transmission lines such as the microstrip line have become very important.

Preparatory studies for modelling steam condensation on soluble aerosols

International Nuclear Information System (INIS)

Dunbar, I.H.

1988-01-01

Of the fission products which would be released from the core of an LWR in the event of a severe accident, only the noble gases and possibly some of the iodine (depending on chemical form) are likely not to be in the form of aerosols when they reach the containment building atmosphere. Therefore in order to predict the extent of fission product retention on containment building internal structures, one needs to have a good understanding of aerosol deposition processes and of the factors which affect them. Following a severe accident in an LWR, a major component of the containment atmosphere will be steam. If the thermodynamic conditions allow condensation of this steam, this condensation is most likely to occur on the aerosol particles. A major component of the aerosol formed during the in-vessel release following a severe reactor accident will be fission product caesium. It is believed that much of this will enter the containment in the form of the hydroxide which has a great affinity for water, so particle growth due to steam condensation is likely to be a very important mechanism for retaining radioactive caesium within the containment builing. The author provides a systematic review of the basic chemical and physical issues which must be addressed if the phenomena are to be modelled accurately, and gives recommendations on how computer models of condensation onto soluble aerosols should be constructed. He proposes also to perform a systematic review of the existing literature and to perform small-scale thermodynamic experiments wherever important gaps in the data base are discovered

Metrology concept design of the GAIA basic angle monitoring system

NARCIS (Netherlands)

Veggel, van A.A.; Vink, H.J.P.; Rosielle, P.C.J.N.; Nijmeijer, H.; Wielders, A.A.; Antebi, J.; Lemke, D.

2004-01-01

The GAIA satellite, scheduled for launch in 2010, will make a highly accurate map of our Galaxy. It will measure the position of stars with an accuracy of 50 prad using two telescopes, which are positioned under a 'basic' angle between the the lines-of-sight of the telescopes of 106°. With a Basic

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements

Energy Technology Data Exchange (ETDEWEB)

Dr. Timothy Onasch

2009-09-09

This SBIR Phase I project addressed the critical need for improved characterization of carbonaceous aerosol species in the atmosphere. The proposed work focused on the development of a thermodenuder (TD) system capable of systematically measuring volatility profiles of primary and secondary organic aerosol species and providing insight into the effects of absorbing and nonabsorbing organic coatings on particle absorption properties. This work provided the fundamental framework for the generation of essential information needed for improved predictions of ambient aerosol loadings and radiative properties by atmospheric chemistry models. As part of this work, Aerodyne Research, Inc. (ARI) continued to develop and test, with the final objective of commercialization, an improved thermodenuder system that can be used in series with any aerosol instrument or suite of instruments (e.g., aerosol mass spectrometers-AMS, scanning mobility particle sizers-SMPS, photoacoustic absorption spectrometers-PAS, etc.) to obtain aerosol chemical, physical, and optical properties as a function of particle volatility. In particular, we provided the proof of concept for the direct coupling of our improved TD design with a full microphysical model to obtain volatility profiles for different organic aerosol components and to allow for meaningful comparisons between different TD-derived aerosol measurements. In a TD, particles are passed through a heated zone and a denuding (activated charcoal) zone to remove semi-volatile material. Changes in particle size, number concentration, optical absorption, and chemical composition are subsequently detected with aerosol instrumentation. The aerosol volatility profiles provided by the TD will strengthen organic aerosol emission inventories, provide further insight into secondary aerosol formation mechanisms, and provide an important measure of particle absorption (including brown carbon contributions and identification, and absorption enhancements

The basics of item response theory using R

CERN Document Server

Baker, Frank B

2017-01-01

This graduate-level textbook is a tutorial for item response theory that covers both the basics of item response theory and the use of R for preparing graphical presentation in writings about the theory. Item response theory has become one of the most powerful tools used in test construction, yet one of the barriers to learning and applying it is the considerable amount of sophisticated computational effort required to illustrate even the simplest concepts. This text provides the reader access to the basic concepts of item response theory freed of the tedious underlying calculations. It is intended for those who possess limited knowledge of educational measurement and psychometrics. Rather than presenting the full scope of item response theory, this textbook is concise and practical and presents basic concepts without becoming enmeshed in underlying mathematical and computational complexities. Clearly written text and succinct R code allow anyone familiar with statistical concepts to explore and apply item re...

Application of the basic concepts of dynamic materials accountancy to the Tokai spent fuel reprocessing facilityssing facility

International Nuclear Information System (INIS)

Lovett, J.E.; Ikawa, Koji; Hirata, Mitsuho; Augustson, R.H.

1980-11-01

During 1978 and 1979 individuals from the International Atomic Energy Agency, the Los Alamos Scientific Laboratory, and the Japan Atomic Energy Research Institute investigated the feasibility of applying the basic concepts of dynamic materials accountancy to PNC-Tokai reprocessing facility in Japan. The system developed for Tokai requires weekly in-process physical inventories for the process MBA, and allows 2-3 additional days for completion of measurements and for data reduction and evaluation. The study concluded that such a system would be feasible, and recommended that an actual field test should be conducted as soon as feasible. (author)

Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

Science.gov (United States)

McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

2011-09-01

Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA

Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

Directory of Open Access Journals (Sweden)

G. R. McMeeking

2011-09-01

Full Text Available Black carbon (BC aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2 measurements of refractory BC (rBC mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA operated by the Facility for Airborne Atmospheric Measurements (FAAM. We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS and used positive matrix factorization to separate hydrocarbon-like (HOA and oxygenated organic aerosols (OOA. We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NO_x ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NO_x and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA did change for

Particle size distribution of aerosols sprayed from household hand-pump sprays containing fluorine-based and silicone-based compounds.

Science.gov (United States)

Kawakami, Tsuyoshi; Isama, Kazuo; Ikarashi, Yoshiaki

2015-01-01

Japan has published safety guideline on waterproof aerosol sprays. Furthermore, the Aerosol Industry Association of Japan has adopted voluntary regulations on waterproof aerosol sprays. Aerosol particles of diameter less than 10 µm are considered as "fine particles". In order to avoid acute lung injury, this size fraction should account for less than 0.6% of the sprayed aerosol particles. In contrast, the particle size distribution of aerosols released by hand-pump sprays containing fluorine-based or silicone-based compounds have not been investigated in Japan. Thus, the present study investigated the aerosol particle size distribution of 16 household hand-pump sprays. In 4 samples, the ratio of fine particles in aerosols exceeded 0.6%. This study confirmed that several hand-pump sprays available in the Japanese market can spray fine particles. Since the hand-pump sprays use water as a solvent and their ingredients may be more hydrophilic than those of aerosol sprays, the concepts related to the safety of aerosol-sprays do not apply to the hand pump sprays. Therefore, it may be required for the hand-pump spray to develop a suitable method for evaluating the toxicity and to establish the safety guideline.

Characterization of urban aerosol in Cork city (Ireland) using aerosol mass spectrometry

Science.gov (United States)

Dall'Osto, M.; Ovadnevaite, J.; Ceburnis, D.; Martin, D.; Healy, R. M.; O'Connor, I. P.; Kourtchev, I.; Sodeau, J. R.; Wenger, J. C.; O'Dowd, C.

2013-05-01

Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS) were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC), sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS) and was also found to comprise organic aerosol as the most abundant species (62%), followed by nitrate (15%), sulphate (9%) and ammonium (9%), and chloride (5%). Positive matrix factorization (PMF) was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA) comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA) comprised 18%, "biomass burning" organic aerosol (BBOA) comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA) comprised 21%, and finally a species type characterized by primary {m/z} peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA), but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively).

Characterization of urban aerosol in Cork city (Ireland using aerosol mass spectrometry

Directory of Open Access Journals (Sweden)

M. Dall'Osto

2013-05-01

Full Text Available Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC, sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS and was also found to comprise organic aerosol as the most abundant species (62%, followed by nitrate (15%, sulphate (9% and ammonium (9%, and chloride (5%. Positive matrix factorization (PMF was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA comprised 18%, "biomass burning" organic aerosol (BBOA comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA comprised 21%, and finally a species type characterized by primary extit{m/z}~peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA, but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively.

Estimating marine aerosol particle volume and number from Maritime Aerosol Network data

Directory of Open Access Journals (Sweden)

A. M. Sayer

2012-09-01

Full Text Available As well as spectral aerosol optical depth (AOD, aerosol composition and concentration (number, volume, or mass are of interest for a variety of applications. However, remote sensing of these quantities is more difficult than for AOD, as it is more sensitive to assumptions relating to aerosol composition. This study uses spectral AOD measured on Maritime Aerosol Network (MAN cruises, with the additional constraint of a microphysical model for unpolluted maritime aerosol based on analysis of Aerosol Robotic Network (AERONET inversions, to estimate these quantities over open ocean. When the MAN data are subset to those likely to be comprised of maritime aerosol, number and volume concentrations obtained are physically reasonable. Attempts to estimate surface concentration from columnar abundance, however, are shown to be limited by uncertainties in vertical distribution. Columnar AOD at 550 nm and aerosol number for unpolluted maritime cases are also compared with Moderate Resolution Imaging Spectroradiometer (MODIS data, for both the present Collection 5.1 and forthcoming Collection 6. MODIS provides a best-fitting retrieval solution, as well as the average for several different solutions, with different aerosol microphysical models. The "average solution" MODIS dataset agrees more closely with MAN than the "best solution" dataset. Terra tends to retrieve lower aerosol number than MAN, and Aqua higher, linked with differences in the aerosol models commonly chosen. Collection 6 AOD is likely to agree more closely with MAN over open ocean than Collection 5.1. In situations where spectral AOD is measured accurately, and aerosol microphysical properties are reasonably well-constrained, estimates of aerosol number and volume using MAN or similar data would provide for a greater variety of potential comparisons with aerosol properties derived from satellite or chemistry transport model data. However, without accurate AOD data and prior knowledge of

Getting Back to Basics (& Acidics)

Science.gov (United States)

Rhodes, Sam

2006-01-01

This article describes a few novel acid-base experiments intended to introduce students to the basic concepts of acid-base chemistry and provide practical examples that apply directly to the study of biology and the human body. Important concepts such as the reaction between carbon dioxide and water, buffers and protein denaturation, are covered.…

Basic Thermodynamics

International Nuclear Information System (INIS)

Duthil, P

2014-01-01

The goal of this paper is to present a general thermodynamic basis that is useable in the context of superconductivity and particle accelerators. The first part recalls the purpose of thermodynamics and summarizes its important concepts. Some applications, from cryogenics to magnetic systems, are covered. In the context of basic thermodynamics, only thermodynamic equilibrium is considered

Basic Thermodynamics

Energy Technology Data Exchange (ETDEWEB)

Duthil, P [Orsay, IPN (France)

2014-07-01

The goal of this paper is to present a general thermodynamic basis that is useable in the context of superconductivity and particle accelerators. The first part recalls the purpose of thermodynamics and summarizes its important concepts. Some applications, from cryogenics to magnetic systems, are covered. In the context of basic thermodynamics, only thermodynamic equilibrium is considered.

Basic Writing Concepts for Scientists and Engineers.

Science.gov (United States)

Mitchell, John H.

1980-01-01

Notes the differences between poetry and technical communication. Charges English teacher/humanists with confusing students about emotional writing, style, and effective technical communication. Offers five concepts that technical writing teachers can use to place "style" on a rational basis and to make students understand the true purposes of…

Numerical simulations of homogeneous freezing processes in the aerosol chamber AIDA

Directory of Open Access Journals (Sweden)

W. Haag

2003-01-01

Full Text Available The homogeneous freezing of supercooled H2SO4/H2O aerosols in an aerosol chamber is investigated with a microphysical box model using the activity parameterization of the nucleation rate by Koop et al. (2000. The simulations are constrained by measurements of pressure, temperature, total water mixing ratio, and the initial aerosol size distribution, described in a companion paper Möhler et al. (2003. Model results are compared to measurements conducted in the temperature range between 194 and 235 K, with cooling rates in the range between 0.5 and 2.6 K min-1, and at air pressures between 170 and 1000 hPa. The simulations focus on the time history of relative humidity with respect to ice, aerosol size distribution, partitioning of water between gas and particle phase, onset times of freezing, freezing threshold relative humidities, aerosol chemical composition at the onset of freezing, and the number of nucleated ice crystals. The latter four parameters can be inferred from the experiments, the former three aid in interpreting the measurements. Sensitivity studies are carried out to address the relative importance of uncertainties of basic quantities such as temperature, total H2O mixing ratio, aerosol size spectrum, and deposition coefficient of H2O molecules on ice. The ability of the numerical simulations to provide detailed explanations of the observations greatly increases confidence in attempts to model this process under real atmospheric conditions, for instance with regard to the formation of cirrus clouds or polar stratospheric ice clouds, provided that accurate temperature and humidity measurements are available.

Aerosol Scrubbing Performance Test for Self-Priming Scrubbing Nozzle Submerged in Water Pool

Energy Technology Data Exchange (ETDEWEB)

Lee, Doo Yong; Jung, Woo Young; Lee, Hyun Chul; Lee, Jong Chan; Kim, Gyu Tae; Song, Yong Jae [FNC Technology Co., Yongin (Korea, Republic of)

2016-10-15

A scrubbing nozzle is one of the key components for a wet scrubber process based Containment Filtered Venting System (CFVS). As a part of a development of Korean CFVS, a self-priming scrubbing nozzle shown in Fig. 1 has been developed based on the well-known venturi scrubber concept. The thermal-hydraulic performances such as the pressure drop across the nozzle, water suction behavior and droplet generation inside throat have been tested in the non-submerged condition as well as submerged condition. The self-priming scrubbing nozzle used for the wet scrubber based CFVS has been developed, which is submerged in the water pool. When there is gas flow at the inlet of the nozzle, the pool water is passively sucked from the water suction slit. The fine droplets generated inside the throat capture the aerosol particles and is discharged into the water pool. In the water pool, the pool scrubbing happens. The aerosol scrubbing performance tests for the developed self-priming scrubbing nozzle has been conducted under the operational conditions such as different aerosol sizes, different carrier gas steam fractions, different, different pool water level and nozzle inlet pressure. The major findings are as follows. (1) Aerosol scrubbing efficiency increases with the increase of the aerosol size. (2) Aerosol scrubbing efficiency increases with the increase of the carrier gas steam fraction. (3) Aerosol scrubbing.

Aerosol Scrubbing Performance Test for Self-Priming Scrubbing Nozzle Submerged in Water Pool

International Nuclear Information System (INIS)

Lee, Doo Yong; Jung, Woo Young; Lee, Hyun Chul; Lee, Jong Chan; Kim, Gyu Tae; Song, Yong Jae

2016-01-01

A scrubbing nozzle is one of the key components for a wet scrubber process based Containment Filtered Venting System (CFVS). As a part of a development of Korean CFVS, a self-priming scrubbing nozzle shown in Fig. 1 has been developed based on the well-known venturi scrubber concept. The thermal-hydraulic performances such as the pressure drop across the nozzle, water suction behavior and droplet generation inside throat have been tested in the non-submerged condition as well as submerged condition. The self-priming scrubbing nozzle used for the wet scrubber based CFVS has been developed, which is submerged in the water pool. When there is gas flow at the inlet of the nozzle, the pool water is passively sucked from the water suction slit. The fine droplets generated inside the throat capture the aerosol particles and is discharged into the water pool. In the water pool, the pool scrubbing happens. The aerosol scrubbing performance tests for the developed self-priming scrubbing nozzle has been conducted under the operational conditions such as different aerosol sizes, different carrier gas steam fractions, different, different pool water level and nozzle inlet pressure. The major findings are as follows. (1) Aerosol scrubbing efficiency increases with the increase of the aerosol size. (2) Aerosol scrubbing efficiency increases with the increase of the carrier gas steam fraction. (3) Aerosol scrubbing

Radioactive aerosols

International Nuclear Information System (INIS)

Chamberlain, A.C.

1991-01-01

Radon. Fission product aerosols. Radioiodine. Tritium. Plutonium. Mass transfer of radioactive vapours and aerosols. Studies with radioactive particles and human subjects. Index. This paper explores the environmental and health aspects of radioactive aerosols. Covers radioactive nuclides of potential concern to public health and applications to the study of boundary layer transport. Contains bibliographic references. Suitable for environmental chemistry collections in academic and research libraries

Use of modulated excitation signals in ultrasound. Part I: Basic concepts and expected benefits

DEFF Research Database (Denmark)

Misaridis, Thanassis; Jensen, Jørgen Arendt

2005-01-01

This paper, the first from a series of three papers on the application of coded excitation signals in medical ultrasound, discusses the basic principles and ultrasound-related problems of pulse compression. The concepts of signal modulation and matched filtering are given, and a simple model...... of attenuation relates the matched filter response with the ambiguity function, known from radar. Based on this analysis and the properties of the ambiguity function, the selection of coded waveforms suitable for ultrasound imaging is discussed. It is shown that linear frequency modulation (FM) signals have...... that in the case of linear FM signals, a SNR improvement of 12 to 18 dB can be expected for large imaging depths in attenuating media, without any depth-dependent filter compensation. In contrast, nonlinear FM modulation and binary codes are shown to give a SNR improvement of only 4 to 9 dB when processed...

Significant and Basic Innovations in Urban Planning

Science.gov (United States)

Kolyasnikov, V. A.

2017-11-01

The article considers the development features of the innovative urban planning in the USSR and Russia in XVIII - XX centuries. Innovative urban planning is defined as an activity on innovations creation and their implementation to obtain a socio-economic, political, environmental or other effect. In the course of urban development history this activity represents a cyclic wave process in which there are phases of rise and fall. The study of cyclic waves in the development of innovative urban planning uses the concept of basic and epochal innovations selection. This concept was developed by scientists for the study of cyclic wave processes in economics. Its adaptation to the conditions of innovative urban planning development allows one to introduce the concept of “basic innovation” and “significant innovation” in the theory and practice of settlement formation and their systems as well as to identify opportunities to highlight these innovations in the history of Russian urban planning. From these positions, six innovation waves committed to the urban development over the past 300 years are being investigated. The observed basic innovations in the domestic urban area show that urban development is a vital area for ensuring the country’s geopolitical security. Basic innovations are translated in time and modernized under new conditions of urban planning development. In this regard, we can predict the development of four basic innovations in post-Soviet Russia.

Aerosol studies

International Nuclear Information System (INIS)

Cristy, G.A.; Fish, M.E.

1978-01-01

As part of the continuing studies of the effects of very severe reactor accidents, an effort was made to develop, test, and improve simple, effective, and inexpensive methods by which the average citizen, using only materials readily available, could protect his residence, himself, and his family from injury by toxic aerosols. The methods for protection against radioactive aerosols should be equally effective against a clandestine biological attack by terrorists. The results of the tests to date are limited to showing that spores of the harmless bacterium, bacillus globegii (BG), can be used as a simulant for the radioactive aerosols. An aerosol generator of Lauterbach type was developed which will produce an essentially monodisperse aerosol at the rate of 10 9 spores/min. Analytical techniques have been established which give reproducible results. Preliminary field tests have been conducted to check out the components of the system. Preliminary tests of protective devices, such as ordinary vacuum sweepers, have given protection factors of over 1000

Aerosol optical thickness retrieval over land and water using SCIAMACHY/GOME data

NARCIS (Netherlands)

Kusmierczyk-Michulec, J.; Leeuw, G. de

2005-01-01

An algorithm for the retrieval of the aerosol optical thickness over land and over water from SCIAMACHY (SCanning Imaging Absorption SpectroMeter for Atmospheric ChartographY) is presented. Because calibrated data are not yet available for the SCIAMACHY channels used by the algorithm, the concepts

Aerosol Climate Time Series in ESA Aerosol_cci

Science.gov (United States)

Popp, Thomas; de Leeuw, Gerrit; Pinnock, Simon

2016-04-01

Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. Meanwhile, full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer, but also from ATSR instruments and the POLDER sensor), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which were also validated and improved in the reprocessing. For the three ATSR algorithms the use of an ensemble method was tested. The paper will summarize and discuss the status of dataset reprocessing and validation. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension

Odin-OSIRIS stratospheric aerosol data product and SAGE III intercomparison

Directory of Open Access Journals (Sweden)

A. E. Bourassa

2012-01-01

Full Text Available The scattered sunlight measurements made by the Optical Spectrograph and InfraRed Imaging System (OSIRIS on the Odin spacecraft are used to retrieve vertical profiles of stratospheric aerosol extinction at 750 nm. The recently released OSIRIS Version 5 data product contains the first publicly released stratospheric aerosol extinction retrievals, and these are now available for the entire Odin mission, which extends from the present day back to launch in 2001. A proof-of-concept study for the retrieval of stratospheric aerosol extinction from limb scatter measurements was previously published and the Version 5 data product retrievals are based on this work, but incorporate several important improvements to the algorithm. One of the primary changes is the use of a new retrieval vector that greatly improves the sensitivity to aerosol scattering by incorporating a forward modeled calculation of the radiance from a Rayleigh atmosphere. Additional improvements include a coupled retrieval of the effective albedo, a new method for normalization of the retrieval vector to improve signal-to-noise, and the use of an initial guess that is representative of very low background aerosol loading conditions, which allows for maximal retrieval range. Furthermore, the Version 5 data set is compared to Stratospheric Aerosol and Gas Experiment (SAGE III 755 nm extinction profiles during the almost four years of mission overlap from 2002 to late 2005. The vertical structure in coincident profile measurements is well correlated and the statistics on a relatively large set of tight coincident measurements show agreement between the measurements from the two instruments to within approximately 10% throughout the 15 to 25 km altitude range, which covers the bulk of the stratospheric aerosol layer for the mid and high latitude cases studied here.

From basic needs to basic rights.

Science.gov (United States)

Facio, A

1995-06-01

After arriving at an understanding that basic rights refer to all human needs, it is clear that a recognition of the basic needs of female humans must precede the realization of their rights. The old Women in Development (WID) framework only understood women's needs from an androcentric perspective which was limited to practical interests. Instead, women's primary need is to be free from their subordination to men. Such an understanding places all of women's immediate needs in a new light. A human rights approach to development would see women not as beneficiaries but as people entitled to enjoy the benefits of development. Discussion of what equality before the law should mean to women began at the Third World Conference on Women in Nairobi where the issue of violence against women was first linked to development. While debate continues about the distinction between civil and political rights and economic, social, and cultural rights, the realities of women's lives do not permit such a distinction. The concept of the universality of human rights did not become codified until the UN proclaimed the Universal Declaration of Human Rights in 1948. The declaration has been criticized by feminists because the view of human rights it embodies has been too strongly influenced by a liberal Western philosophy which stresses individual rights and because it is ambiguous on the distinction between human rights and the rights of a citizen. The protection of rights afforded by the Declaration, however, should not be viewed as a final achievement but as an ongoing struggle. International conferences have led to an analysis of the human-rights approach to sustainable development which concludes that women continue to face the routine denial of their rights. Each human right must be redefined from the perspective of women's needs, which must also be redefined. Women must forego challenging the concept of the universality of human rights in order to overcome the argument of cultural

Basic Concepts in G-Protein-Coupled Receptor Homo- and Heterodimerization

Directory of Open Access Journals (Sweden)

Rafael Franco

2007-01-01

Full Text Available Until recently, heptahelical G-protein-coupled receptors (GPCRs were considered to be expressed as monomers on the cell surface of neuronal and non-neuronal cells. It is now becoming evident that this view must be overtly changed since these receptors can form homodimers, heterodimers, and higher-order oligomers on the plasma membrane. Here we discuss some of the basics and some new concepts of receptor homo- and heteromerization. Dimers-oligomers modify pharmacology, trafficking, and signaling of receptors. First of all, GPCR dimers must be considered as the main molecules that are targeted by neurotransmitters or by drugs. Thus, binding data must be fitted to dimer-based models. In these models, it is considered that the conformational changes transmitted within the dimer molecule lead to cooperativity. Cooperativity must be taken into account in the binding of agonists-antagonists-drugs and also in the binding of the so-called allosteric modulators. Cooperativity results from the intramolecular cross-talk in the homodimer. As an intramolecular cross-talk in the heterodimer, the binding of one neurotransmitter to one receptor often affects the binding of the second neurotransmitter to the partner receptor. Coactivation of the two receptors in a heterodimer can change completely the signaling pathway triggered by the neurotransmitter as well as the trafficking of the receptors. Heterodimer-specific drugs or dual drugs able to activate the two receptors in the heterodimer simultaneously emerge as novel and promising drugs for a variety of central nervous system (CNS therapeutic applications.

MATRIX-VBS Condensing Organic Aerosols in an Aerosol Microphysics Model

Science.gov (United States)

Gao, Chloe Y.; Tsigaridis, Konstas; Bauer, Susanne E.

2015-01-01

The condensation of organic aerosols is represented in a newly developed box-model scheme, where its effect on the growth and composition of particles are examined. We implemented the volatility-basis set (VBS) framework into the aerosol mixing state resolving microphysical scheme Multiconfiguration Aerosol TRacker of mIXing state (MATRIX). This new scheme is unique and advances the representation of organic aerosols in models in that, contrary to the traditional treatment of organic aerosols as non-volatile in most climate models and in the original version of MATRIX, this new scheme treats them as semi-volatile. Such treatment is important because low-volatility organics contribute significantly to the growth of particles. The new scheme includes several classes of semi-volatile organic compounds from the VBS framework that can partition among aerosol populations in MATRIX, thus representing the growth of particles via condensation of low volatility organic vapors. Results from test cases representing Mexico City and a Finish forrest condistions show good representation of the time evolutions of concentration for VBS species in the gas phase and in the condensed particulate phase. Emitted semi-volatile primary organic aerosols evaporate almost completely in the high volatile range, and they condense more efficiently in the low volatility range.

Aerosol Climate Time Series Evaluation In ESA Aerosol_cci

Science.gov (United States)

Popp, T.; de Leeuw, G.; Pinnock, S.

2015-12-01

Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. By the end of 2015 full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which are also validated. The paper will summarize and discuss the results of major reprocessing and validation conducted in 2015. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension with successor instruments of the Sentinel family will be described and the complementarity of the different satellite aerosol products

Rethinking basic concepts in ICRP's system of dose limitation

International Nuclear Information System (INIS)

Mills, W.A.; Mossman, K.L.

1991-01-01

The present criterion for radiation protection appears to be exposure reduction rather than adequate protection of health. The 1990 ICRP draft recommendations for a system of dose limitation would further implement this more restrictive criterion by implementing certain academic concepts and assumptions. These concepts and assumptions are discussed and the suggestion is made that the radiation protection community needs to carefully examine the need for the complex system proposed

New Federalism: Back to Basics.

Science.gov (United States)

Durenberger, Dave

1983-01-01

The senator explains the basic concepts of New Federalism, including a rethinking of responsibilities and intergovernmental relations and a reconsideration of the role of state and local government. (SK)

Algorithm of Data Reduce in Determination of Aerosol Particle Size Distribution at Damps/C

International Nuclear Information System (INIS)

Muhammad-Priyatna; Otto-Pribadi-Ruslanto

2001-01-01

The analysis had to do for algorithm of data reduction on Damps/C (Differential Mobility Particle Sizer with Condensation Particle Counter) system, this is for determine aerosol particle size distribution with range 0,01 μm to 1 μm in diameter. Damps/C (Differential Mobility Particle Sizer with Condensation Particle Counter) system contents are software and hardware. The hardware used determine of mobilities of aerosol particle and so the software used determine aerosol particle size distribution in diameter. The mobilities and diameter particle had connection in the electricity field. That is basic program for reduction of data and particle size conversion from particle mobility become particle diameter. The analysis to get transfer function value, Ω, is 0.5. The data reduction program to do conversation mobility basis become diameter basis with number efficiency correction, transfer function value, and poly charge particle. (author)

Improving the Lung Delivery of Nasally Administered Aerosols During Noninvasive Ventilation—An Application of Enhanced Condensational Growth (ECG)

Science.gov (United States)

Tian, Geng; Hindle, Michael

2011-01-01

Abstract Background Aerosol drug delivery during noninvasive ventilation (NIV) is known to be inefficient due to high depositional losses. To improve drug delivery efficiency, the concept of enhanced condensational growth (ECG) was recently proposed in which a submicrometer or nanoaerosol reduces extrathoracic deposition and subsequent droplet size increase promotes lung retention. The objective of this study was to provide proof-of-concept that the ECG approach could improve lung delivery of nasally administered aerosols under conditions consistent with NIV. Methods Aerosol deposition and size increase were evaluated in an adult nose–mouth–throat (NMT) replica geometry using both in vitro experiments and CFD simulations. For the ECG delivery approach, separate streams of a submicrometer aerosol and warm (39°C) saturated air were generated and delivered to the right and left nostril inlets, respectively. A control case was also considered in which an aerosol with a mass median aerodynamic diameter (MMAD) of 4.67 μm was delivered to the model. Results In vitro experiments showed that the ECG approach significantly reduced the drug deposition fraction in the NMT geometry compared with the control case [14.8 (1.83)%—ECG vs. 72.6 (3.7)%—control]. Aerosol size increased from an initial MMAD of 900 nm to a size of approximately 2 μm at the exit of the NMT geometry. Results of the CFD model were generally in good agreement with the experimental findings. Based on CFD predictions, increasing the delivery temperature of the aerosol stream from 21 to 35°C under ECG conditions further reduced the total NMT drug deposition to 5% and maintained aerosol growth by ECG to approximately 2 μm. Conclusions Application of the ECG approach may significantly improve the delivery of pharmaceutical aerosols during NIV and may open the door for using the nasal route to routinely deliver pulmonary medications. PMID:21410327

Basic Finite Element Method

International Nuclear Information System (INIS)

Lee, Byeong Hae

1992-02-01

This book gives descriptions of basic finite element method, which includes basic finite element method and data, black box, writing of data, definition of VECTOR, definition of matrix, matrix and multiplication of matrix, addition of matrix, and unit matrix, conception of hardness matrix like spring power and displacement, governed equation of an elastic body, finite element method, Fortran method and programming such as composition of computer, order of programming and data card and Fortran card, finite element program and application of nonelastic problem.

Overview of 3D-TRACE, a NASA Initiative in Three-Dimensional Tomography of the Aerosol-Cloud Environment

Science.gov (United States)

Davis, Anthony; Diner, David; Yanovsky, Igor; Garay, Michael; Xu, Feng; Bal, Guillaume; Schechner, Yoav; Aides, Amit; Qu, Zheng; Emde, Claudia

2013-04-01

microphysical properties, can be reconstructed from multi-angle/multi-spectral imaging radiometry and, more and more, polarimetry. Specific technologies of interest are computed tomography (reconstruction from projections), optical tomography (using cross-pixel radiation transport in the diffusion limit), stereoscopy (depth/height retrievals), blind source and scale separation (signal unmixing), and disocclusion (information recovery in the presence of obstructions). Later on, these potentially powerful inverse problem solutions will be fully integrated in a versatile satellite data analysis toolbox. At present, we can report substantial progress at the component level. Specifically, we will focus on the most elementary problems in atmospheric tomography with an emphasis on the vastly under-exploited class of multi-pixel techniques. One basic problem is to infer the outer shape and mean opacity of 3D clouds, along with a bulk measure of cloud particle size. Another is to separate high and low cloud layers based on their characteristically different spatial textures. Yet another is to reconstruct the 3D spatial distribution of aerosol density based on passive imaging. This suite of independent feasibility studies amounts to a compelling proofof- concept for the ambitious 3D-Tomographic Reconstruction of the Aerosol-Cloud Environment (3D-TRACE) project as a whole.

Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

Energy Technology Data Exchange (ETDEWEB)

Turner, David, D.; Ferrare, Richard, A.

2011-07-06

The 'Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds' project focused extensively on the analysis and utilization of water vapor and aerosol profiles derived from the ARM Raman lidar at the Southern Great Plains ARM site. A wide range of different tasks were performed during this project, all of which improved quality of the data products derived from the lidar or advanced the understanding of atmospheric processes over the site. These activities included: upgrading the Raman lidar to improve its sensitivity; participating in field experiments to validate the lidar aerosol and water vapor retrievals; using the lidar aerosol profiles to evaluate the accuracy of the vertical distribution of aerosols in global aerosol model simulations; examining the correlation between relative humidity and aerosol extinction, and how these change, due to horizontal distance away from cumulus clouds; inferring boundary layer turbulence structure in convective boundary layers from the high-time-resolution lidar water vapor measurements; retrieving cumulus entrainment rates in boundary layer cumulus clouds; and participating in a field experiment that provided data to help validate both the entrainment rate retrievals and the turbulent profiles derived from lidar observations.

Lidar data assimilation for improved analyses of volcanic aerosol events

Science.gov (United States)

Lange, Anne Caroline; Elbern, Hendrik

2014-05-01

Observations of hazardous events with release of aerosols are hardly analyzable by today's data assimilation algorithms, without producing an attenuating bias. Skillful forecasts of unexpected aerosol events are essential for human health and to prevent an exposure of infirm persons and aircraft with possibly catastrophic outcome. Typical cases include mineral dust outbreaks, mostly from large desert regions, wild fires, and sea salt uplifts, while the focus aims for volcanic eruptions. In general, numerical chemistry and aerosol transport models cannot simulate such events without manual adjustments. The concept of data assimilation is able to correct the analysis, as long it is operationally implemented in the model system. Though, the tangent-linear approximation, which describes a substantial precondition for today's cutting edge data assimilation algorithms, is not valid during unexpected aerosol events. As part of the European COPERNICUS (earth observation) project MACC II and the national ESKP (Earth System Knowledge Platform) initiative, we developed a module that enables the assimilation of aerosol lidar observations, even during unforeseeable incidences of extreme emissions of particulate matter. Thereby, the influence of the background information has to be reduced adequately. Advanced lidar instruments comprise on the one hand the aspect of radiative transfer within the atmosphere and on the other hand they can deliver a detailed quantification of the detected aerosols. For the assimilation of maximal exploited lidar data, an appropriate lidar observation operator is constructed, compatible with the EURAD-IM (European Air Pollution and Dispersion - Inverse Model) system. The observation operator is able to map the modeled chemical and physical state on lidar attenuated backscatter, transmission, aerosol optical depth, as well as on the extinction and backscatter coefficients. Further, it has the ability to process the observed discrepancies with lidar

Basic concept of fuel safety design and assessment for sodium-cooled fast reactor

International Nuclear Information System (INIS)

Nakae, Nobuo; Baba, Toshikazu; Kamimura, Katsuichiro

2013-03-01

'Philosophy in Safety Evaluation of Fast Breeder Reactors' was published as a guideline for safety design and safety evaluation of Sodium-Cooled Fast Reactor in Japan. This guideline points out that cladding creep and swelling due to internal pressure should be taken into account since the fuel is used under high temperature and high burnup, and that fuel assembly deformation and the prevention from coolant channel blockage should be taken into account in viewpoints of nuclear and thermal hydraulic design. However, the requirements including their criteria and evaluation items are not described. Two other domestic guidelines related to core design are applied for fuel design of fast reactor, but the description is considered to not be enough to practically use. In addition, technical standard for nuclear fuel used in power reactors is also applied for fuel inspection. Therefore, the technical standard and guideline for fuel design and safety evaluation are considered to be very important issue for nuclear safety regulation. This document has been developed according to the following steps: The guidelines and the technical standards, which are prepared in foreign countries and international organization, were reviewed. The technical background concerning fuel design and safety evaluation for fast reactor was collected and summarized in the world wide scale. The basic concept of fuel safety design and assessment for sodium-cooled fast reactor was developed by considering a wide range of views of the specialists in Japan. In order to discuss the content with foreign specialists IAEA Consultancy Meetings have been held on January, 2011 and January, 2012. The participants of the meeting came from USA, UK, EC, India, China and South Korea. The specialists of IAEA and JNES were also joined. Although this document is prepared for application to 'Monju'(prototype LMFR), it may be applied to experimental, demonstration and commercial types of LMFR after revising it by taking

Aerosol retrieval experiments in the ESA Aerosol_cci project

Directory of Open Access Journals (Sweden)

T. Holzer-Popp

2013-08-01

Full Text Available Within the ESA Climate Change Initiative (CCI project Aerosol_cci (2010–2013, algorithms for the production of long-term total column aerosol optical depth (AOD datasets from European Earth Observation sensors are developed. Starting with eight existing pre-cursor algorithms three analysis steps are conducted to improve and qualify the algorithms: (1 a series of experiments applied to one month of global data to understand several major sensitivities to assumptions needed due to the ill-posed nature of the underlying inversion problem, (2 a round robin exercise of "best" versions of each of these algorithms (defined using the step 1 outcome applied to four months of global data to identify mature algorithms, and (3 a comprehensive validation exercise applied to one complete year of global data produced by the algorithms selected as mature based on the round robin exercise. The algorithms tested included four using AATSR, three using MERIS and one using PARASOL. This paper summarizes the first step. Three experiments were conducted to assess the potential impact of major assumptions in the various aerosol retrieval algorithms. In the first experiment a common set of four aerosol components was used to provide all algorithms with the same assumptions. The second experiment introduced an aerosol property climatology, derived from a combination of model and sun photometer observations, as a priori information in the retrievals on the occurrence of the common aerosol components. The third experiment assessed the impact of using a common nadir cloud mask for AATSR and MERIS algorithms in order to characterize the sensitivity to remaining cloud contamination in the retrievals against the baseline dataset versions. The impact of the algorithm changes was assessed for one month (September 2008 of data: qualitatively by inspection of monthly mean AOD maps and quantitatively by comparing daily gridded satellite data against daily averaged AERONET sun

The analysis and perspectives of studying basic and special types of self-determination according to A.L. Zhuravlev’s and A.B. Kupreichenko’s concept.

Directory of Open Access Journals (Sweden)

Vorobieva, A.E.

2015-07-01

Full Text Available An analysis of Russian and foreign ways of understanding the phenomenon of self-determination has been performed. It has been found that the concept of individual and group self-determination by A.L. Zhuravlev and A.B. Kupreichenko is the most developed in modern Russian psychological science. Using the concept as a basis, the conceptual schemes (made by A.E. Vorobieva and A.A. Akbarova of studies of personal, moral, social and economic self-determination were considered as the examples of the basic and special types of self-determination. Moral self-determination was studied with questions about ideas of morality, moral strategies and personality orientation, attitude toward unethical phenomena, ability for self-regulation and emotional intellect. Social and economic self-determination were studied with questions that show one’s social level, satisfaction with economic and social status and their dynamics, a valuation of favorable circumstances for an increase of status and economic activity. Value and anti-value, spheres and forms of showing of social and living personality’s activity were also determined. Fundamental differences (variability, success criteria, implementation in behavior, a level of ability to control a process, the role of external factors and similarities (successfulness, a formation level, a range, dynamics, conceptions, strategy, values, factors between the components of the conceptual schemes of these types of selfdetermination were identified. The principles of studying (proportion of basic and specific types of self-determination, a display of resultative, procedural and formal-dynamic characteristics, consideration of factors of different levels of basic and special types of self-determination were suggested.

The Two-Column Aerosol Project: Phase I - Overview and Impact of Elevated Aerosol Layers on Aerosol Optical Depth

Science.gov (United States)

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon P.; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.;

The Two-Column Aerosol Project: Phase I - Overview and Impact of Elevated Aerosol Layers on Aerosol Optical Depth

Energy Technology Data Exchange (ETDEWEB)

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.; Hair, John; Hostetler, Chris A.; Hubbe, John M.; Jefferson, Anne; Johnson, Roy; Kassianov, Evgueni I.; Kluzek, Celine D.; Kollias, Pavlos; Lamer, Katia; Lantz, K.; Mei, Fan; Miller, Mark A.; Michalsky, Joseph; Ortega, Ivan; Pekour, Mikhail S.; Rogers, Ray; Russell, P.; Redemann, Jens; Sedlacek, Art; Segal Rozenhaimer, Michal; Schmid, Beat; Shilling, John E.; Shinozuka, Yohei; Springston, Stephen R.; Tomlinson, Jason M.; Tyrrell, Megan; Wilson, Jacqueline; Volkamer, Rainer M.; Zelenyuk, Alla; Berkowitz, Carl M.

2016-01-08

The Two-Column Aerosol Project (TCAP), which was conducted from June 2012 through June 2013, was a unique field study that was designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere at a number of altitudes, from near the surface to as high as 8 km, within two atmospheric columns; one located near the coast of North America (over Cape Cod, MA) and a second over the Atlantic Ocean several hundred kilometers from the coast. TCAP included the yearlong deployment of the U.S. Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) that was located at the base of the Cape Cod column, as well as summer and winter aircraft intensive observation periods of the ARM Aerial Facility. One important finding from TCAP is the relatively common occurrence (on four of six nearly cloud-free flights) of elevated aerosol layers in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). These layers contributed up to 60% of the total aerosol optical depth (AOD) observed in the column. Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning aerosol and nitrate compared to the aerosol found near the surface.

The Two-Column Aerosol Project: Phase I—Overview and impact of elevated aerosol layers on aerosol optical depth

Science.gov (United States)

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon P.; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.; Hair, Johnathan W.; Hostetler, Chris A.; Hubbe, John; Jefferson, Anne; Johnson, Roy; Kassianov, Evgueni I.; Kluzek, Celine D.; Kollias, Pavlos; Lamer, Katia; Lantz, Kathleen; Mei, Fan; Miller, Mark A.; Michalsky, Joseph; Ortega, Ivan; Pekour, Mikhail; Rogers, Ray R.; Russell, Philip B.; Redemann, Jens; Sedlacek, Arthur J.; Segal-Rosenheimer, Michal; Schmid, Beat; Shilling, John E.; Shinozuka, Yohei; Springston, Stephen R.; Tomlinson, Jason M.; Tyrrell, Megan; Wilson, Jacqueline M.; Volkamer, Rainer; Zelenyuk, Alla; Berkowitz, Carl M.

2016-01-01

The Two-Column Aerosol Project (TCAP), conducted from June 2012 through June 2013, was a unique study designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere between and within two atmospheric columns; one fixed near the coast of North America (over Cape Cod, MA) and a second moveable column over the Atlantic Ocean several hundred kilometers from the coast. The U.S. Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) was deployed at the base of the Cape Cod column, and the ARM Aerial Facility was utilized for the summer and winter intensive observation periods. One important finding from TCAP is that four of six nearly cloud-free flight days had aerosol layers aloft in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). These layers contributed up to 60% of the total observed aerosol optical depth (AOD). Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning material and nitrate compared to aerosol found near the surface. In addition, while there was a great deal of spatial and day-to-day variability in the aerosol chemical composition and optical properties, no systematic differences between the two columns were observed.

Basic concepts and assumptions behind the ICRP recommendations

International Nuclear Information System (INIS)

Lindell, B.

1981-03-01

The paper gives a review of the current radiation protection recommendations by the International Commission on Radiological Protection (ICRP). It discusses concepts like stochastic effects, radiation detriments, collective dose, dose equivalent and dose limits. (G.B.)

Special aerosol sources for certification and test of aerosol radiometers

International Nuclear Information System (INIS)

Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E.

1991-01-01

The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author)

Special aerosol sources for certification and test of aerosol radiometers

Energy Technology Data Exchange (ETDEWEB)

Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E. (Union Research Institute of Instrumentation, Moscow (USSR))

1991-01-01

The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author).

Aerosols and the lungs

International Nuclear Information System (INIS)

1987-01-01

The lectures of the colloquium are discussed in summary form. There were 5 lectures on aerosol deposition, 5 on aerosol elimination, 7 on toxicology, and 7 on the uses of aerosols in medical therapy. In some cases aerosols with radioactive labels were used. Several lectures reviewed the kinetics and toxicology of airborne environmental pollutants. (MG) [de

Basic nucleonics. 2. ed.

International Nuclear Information System (INIS)

Guzman, M.E.

1989-01-01

This book is oriented mainly towards professionals who are not physicists or experts in nuclear sciences, physicians planning to specialize in nuclear medicine or radiotherapy and technicians involved in nuclear applications. The book covers the fundamental concepts of nuclear science and technology in a simple and ordered fashion. Theory is illustrated with appropriate exercises and answers. With 17 chapters plus 3 appendices on mathematics, basic concepts are covered in: nuclear science, radioactivity, radiation and matter, nuclear reactions, X rays, shielding and radioprotection

Aerosols and Climate

Indian Academy of Sciences (India)

Large warming by elevated aerosols · AERONET – Global network (NASA) · Slide 25 · Slide 26 · Slide 27 · Slide 28 · Slide 29 · Slide 30 · Slide 31 · Long-term trends - Trivandrum · Enhanced warming over Himalayan-Gangetic region · Aerosol Radiative Forcing Over India _ Regional Aerosol Warming Experiment ...

Impact of cloud-borne aerosol representation on aerosol direct and indirect effects

Directory of Open Access Journals (Sweden)

S. J. Ghan

2006-01-01

Full Text Available Aerosol particles attached to cloud droplets are much more likely to be removed from the atmosphere and are much less efficient at scattering sunlight than if unattached. Models used to estimate direct and indirect effects of aerosols employ a variety of representations of such cloud-borne particles. Here we use a global aerosol model with a relatively complete treatment of cloud-borne particles to estimate the sensitivity of simulated aerosol, cloud and radiation fields to various approximations to the representation of cloud-borne particles. We find that neglecting transport of cloud-borne particles introduces little error, but that diagnosing cloud-borne particles produces global mean biases of 20% and local errors of up to 40% for aerosol, droplet number, and direct and indirect radiative forcing. Aerosol number, aerosol optical depth and droplet number are significantly underestimated in regions and seasons where and when wet removal is primarily by stratiform rather than convective clouds (polar regions during winter, but direct and indirect effects are less biased because of the limited sunlight there and then. A treatment that predicts the total mass concentration of cloud-borne particles for each mode yields smaller errors and runs 20% faster than the complete treatment. The errors are much smaller than current estimates of uncertainty in direct and indirect effects of aerosols, which suggests that the treatment of cloud-borne aerosol is not a significant source of uncertainty in estimates of direct and indirect effects.

Effects of multiple scattering and atmospheric aerosol on the polarization of the twilight sky

International Nuclear Information System (INIS)

Ugolnikov, Oleg S.; Postylyakov, Oleg V.; Maslov, Igor A.

2004-01-01

The paper presents a review of a number of wide-angle polarization CCD-measurements of the twilight sky in V and R color bands with effective wavelengths 550 and 700nm. The basic factors affecting (usually decreasing) the polarization of the twilight sky are the atmospheric aerosol scattering and multiple scattering. These effects were distinguished from each other, and a method of multiple-scattering separation is discussed. The results are compared with the data of numerical simulation of radiative transfer in the atmosphere for different aerosol models. The whole twilight period is divided into different stages with different mechanisms forming the twilight-sky polarization properties

Pseudo-populations a basic concept in statistical surveys

CERN Document Server

Quatember, Andreas

2015-01-01

This book emphasizes that artificial or pseudo-populations play an important role in statistical surveys from finite universes in two manners: firstly, the concept of pseudo-populations may substantially improve users’ understanding of various aspects in the sampling theory and survey methodology; an example of this scenario is the Horvitz-Thompson estimator. Secondly, statistical procedures exist in which pseudo-populations actually have to be generated. An example of such a scenario can be found in simulation studies in the field of survey sampling, where close-to-reality pseudo-populations are generated from known sample and population data to form the basis for the simulation process. The chapters focus on estimation methods, sampling techniques, nonresponse, questioning designs and statistical disclosure control.This book is a valuable reference in understanding the importance of the pseudo-population concept and applying it in teaching and research.

Regional and monthly and clear-sky aerosol direct radiative effect (and forcing derived from the GlobAEROSOL-AATSR satellite aerosol product

Directory of Open Access Journals (Sweden)

G. E. Thomas

2013-01-01

Full Text Available Using the GlobAEROSOL-AATSR dataset, estimates of the instantaneous, clear-sky, direct aerosol radiative effect and radiative forcing have been produced for the year 2006. Aerosol Robotic Network sun-photometer measurements have been used to characterise the random and systematic error in the GlobAEROSOL product for 22 regions covering the globe. Representative aerosol properties for each region were derived from the results of a wide range of literature sources and, along with the de-biased GlobAEROSOL AODs, were used to drive an offline version of the Met Office unified model radiation scheme. In addition to the mean AOD, best-estimate run of the radiation scheme, a range of additional calculations were done to propagate uncertainty estimates in the AOD, optical properties, surface albedo and errors due to the temporal and spatial averaging of the AOD fields. This analysis produced monthly, regional estimates of the clear-sky aerosol radiative effect and its uncertainty, which were combined to produce annual, global mean values of (−6.7 ± 3.9 W m⁻² at the top of atmosphere (TOA and (−12 ± 6 W m⁻² at the surface. These results were then used to give estimates of regional, clear-sky aerosol direct radiative forcing, using modelled pre-industrial AOD fields for the year 1750 calculated for the AEROCOM PRE experiment. However, as it was not possible to quantify the uncertainty in the pre-industrial aerosol loading, these figures can only be taken as indicative and their uncertainties as lower bounds on the likely errors. Although the uncertainty on aerosol radiative effect presented here is considerably larger than most previous estimates, the explicit inclusion of the major sources of error in the calculations suggest that they are closer to the true constraint on this figure from similar methodologies, and point to the need for more, improved estimates of both global aerosol loading and aerosol optical properties.

Particle characterization at rural, suburban and urban aerosol sampling sites in Hungary

International Nuclear Information System (INIS)

Borbely-Kiss, I.; Koltay, E.; Szabo, G.; Meszaros, E.; Molnar, A.; Bozo, L.

1994-01-01

The study of atmospheric aerosols originating from natural and anthropogenic processes is of basic importance for a detailed understanding of the physics and chemistry of the atmosphere. Particle Induced X-ray Emission (PIXE) technique has been used by the authors for studying regularly the elemental composition of rural, suburban, and urban aerosols collected at six sampling sites in Hungary. Observed data presented in terms of concentrations and regional signature values and evaluated wind sector partition and in transport modelling revealed the natural/anthropogenic contribution to the moderate air pollution here. Dry deposition velocities have been deduced for elements V, Cr, Mn, Co, Ni, Cu, Zn, Cd, and Pb. Model calculations based on annual emission data and observed elemental concentrations resulted in total dry and wet deposition masses of the above elements to the territory of the country. At the same time, deduced budget data for the emission and deposition of the constituents indicated whether the country represents a net source or a sink for the above mentioned elements in the regional aerosol transport between neighbouring countries. Evidences have been found for intrusion events of Saharan aerosol to the atmosphere of Hungary. Part of the data collected recently will be evaluated in the frame-work of an international co-ordinated research programme. (author)

Learning basic programming using CLIS through gamification

Science.gov (United States)

Prabawa, H. W.; Sutarno, H.; Kusnendar, J.; Rahmah, F.

2018-05-01

The difficulty of understanding programming concept is a major problem in basic programming lessons. Based on the results of preliminary studies, 60% of students reveal the monotonous of learning process caused by the limited number of media. Children Learning in Science (CLIS) method was chosen as solution because CLIS has facilitated students’ initial knowledge to be optimized into conceptual knowledge. Technological involvement in CLIS (gamification) helped students to understand basic programming concept. This research developed a media using CLIS method with gamification elements to increase the excitement of learning process. This research declared that multimedia is considered good by students, especially regarding the mechanical aspects of multimedia, multimedia elements and aspects of multimedia information structure. Multimedia gamification learning with the CLIS model showed increased number of students’ concept understanding.

TOMS Absorbing Aerosol Index

Data.gov (United States)

Washington University St Louis — TOMS_AI_G is an aerosol related dataset derived from the Total Ozone Monitoring Satellite (TOMS) Sensor. The TOMS aerosol index arises from absorbing aerosols such...

Atmospheric aerosol system: An overview

International Nuclear Information System (INIS)

Prospero, J.M.; Charlson, R.J.; Mohnen, V.; Jaenicke, R.; Delany, A.C.; Moyers, J.; Zoller, W.; Rahn, K.

1983-01-01

Aerosols could play a critical role in many processes which impact on our lives either indirectly (e.g., climate) or directly (e.g., health). However, our ability to assess these possible impacts is constrained by our limited knowledge of the physical and chemical properties of aerosols, both anthropogenic and natural. This deficiency is attributable in part to the fact that aerosols are the end product of a vast array of chemical and physical processes. Consequently, the properties of the aerosol can exhibit a great deal of variability in both time and space. Furthermore, most aerosol studies have focused on measurements of a single aerosol characteristic such as composition or size distribution. Such information is generally not useful for the assessment of impacts because the degree of impact may depend on the integral properties of the aerosol, for example, the aerosol composition as a function of particle size. In this overview we discuss recent work on atmospheric aerosols that illustrates the complex nature of the aerosol chemical and physical system, and we suggest strategies for future research. A major conclusion is that man has had a great impact on the global budgets of certain species, especially sulfur and nitrogen, that play a dominant role in the atmospheric aerosol system. These changes could conceivably affect climate. Large-scale impacts are implied because it has recently been demonstrated that natural and pollutant aerosol episodes can be propagated over great distances. However, at present there is no evidence linking anthropogenic activities with a persistent increase in aerosol concentrations on a global scale. A major problem in assessing man's impact on the atmospheric aerosol system and on global budgets is the absence of aerosol measurements in remote marine and continental areas

Deriving Aerosol Characteristics Over the Ocean from MODIS: Are We There Yet?

Science.gov (United States)

Remer, L. A.; Tanre, D.

2006-12-01

The MODerate resolution Imaging Spectroradiometer (MODIS) has been successfully retrieving aerosol characteristics over the ocean since shortly after the launch of the Terra satellite at the end of 1999. With its wide spectral range (0.47 to 2.13 μm) MODIS is able to derive spectral aerosol optical depth and information on the size of the aerosol particles. The products were quickly validated, the validation confirmed, and the products are now in wide use across the scientific community. The MODIS aerosol products over ocean are an outstanding success story, but are we done? As the years progress and we gain experience in using the products, evaluating them and nudging even greater information from them, we discover new challenges. Firstly, we continue to find issues affecting the integrity of the products we now produce. We need to find methods to reduce the uncertainty introduced by clouds that go beyond the classical concept of cloud masking and cloud contamination. Some of these novel cloud effects on aerosol retrieval include 3D scattering of light from cloud sides. Another issue that needs resolution is the uncertainty introduced by nonspherical particle shapes. Secondly, when MODIS was new we were excited to have spectral optical depth and particle size information. Now we find that aerosol characterization is still incomplete. We need more information. Are we there yet? Well, no, but we can see the future. To meet these new challenges we will need information beyond the spectral radiances that MODIS measures. We can see the future of satellite derivation of aerosol characteristics, and it looks more and more like a multi-sensor future.

Development and validation of the aerosol transport module gamma-FP for evaluating radioactive fission product source terms in a VHTR

Energy Technology Data Exchange (ETDEWEB)

Yoon, Churl; Lim, Hong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-12-15

Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model, and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data, which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

Study on adsorption behavior of radioiodine gas using incense stick aerosol

International Nuclear Information System (INIS)

Murata, Mikio; Noguchi, Hiroshi; Kato, Shohei; Kokubu, Morinobu

1987-01-01

Adsorption of radioactive elemental iodine gas ( 131 I 2 ) on incense stick aerosol particles has been studied to provide basic data for a realistic and precise assessment of dose to the public due to radioiodine released from nuclear facilities. A mixture of iodine gas and aerosol was passed once through a glass vessel to cause the adsorption reaction. The adsorption was studied at different reaction times, initial I 2 gas concentrations and particle number concentrations. The results showed that the adsorption reached an equilibrium in about 2 min at the initial I 2 gas concentration of 10 -10 g/cm 3 . The proportion of iodine adsorbed by the aerosol particles was almost constant, about 25 % at the initial I 2 gas concentrations below 10 -11 g/cm 3 and at the reaction time of 1 min, and decreased with increase of the initial concentration over 10 -11 g/cm 3 . The adsorption isotherm of the aerosol for the gas was obtained from the experimental data. The semi-empirical equations to explain the adsorption reaction were also obtained based on the experimental data and the FUCHS's equation relating to vaporization of a droplet. The sticking probability in the equations was estimated to be 7.6 x 10 -3 . The calculated results using the equations were in good agreement with the experimental ones. (author)

Facility of aerosol filtration

Energy Technology Data Exchange (ETDEWEB)

Duverger de Cuy, G; Regnier, J

1975-04-18

Said invention relates to a facility of aerosol filtration, particularly of sodium aerosols. Said facility is of special interest for fast reactors where sodium fires involve the possibility of high concentrations of sodium aerosols which soon clog up conventional filters. The facility intended for continuous operation, includes at the pre-filtering stage, means for increasing the size of the aerosol particles and separating clustered particles (cyclone separator).

Antarctic aerosols - A review

Science.gov (United States)

Shaw, Glenn E.

1988-02-01

Tropospheric aerosols with the diameter range of half a micron reside in the atmosphere for tens of days and teleconnect Antarctica with other regions by transport that reaches planetary scales of distances; thus, the aerosol on the Antarctic ice represents 'memory modules' of events that took place at regions separated from Antarctica by tens of thousands of kilometers. In terms of aerosol mass, the aerosol species include insoluble crustal products (less than 5 percent), transported sea-salt residues (highly variable but averaging about 10 percent), Ni-rich meteoric material, and anomalously enriched material with an unknown origin. Most (70-90 percent by mass) of the aerosol over the Antarctic ice shield, however, is the 'natural acid sulfate aerosol', apparently deriving from biological processes taking place in the surrounding oceans.

Characterization of urban aerosol using aerosol mass spectrometry and proton nuclear magnetic resonance spectroscopy

Science.gov (United States)

Cleveland, M. J.; Ziemba, L. D.; Griffin, R. J.; Dibb, J. E.; Anderson, C. H.; Lefer, B.; Rappenglück, B.

2012-07-01

Particulate matter was measured during August and September of 2006 in Houston as part of the Texas Air Quality Study II Radical and Aerosol Measurement Project. Aerosol size and composition were determined using an Aerodyne quadrupole aerosol mass spectrometer. Aerosol was dominated by sulfate (4.1 ± 2.6 μg m-3) and organic material (5.5 ± 4.0 μg m-3), with contributions of organic material from both primary (˜32%) and secondary (˜68%) sources. Secondary organic aerosol appears to be formed locally. In addition, 29 aerosol filter samples were analyzed using proton nuclear magnetic resonance (1H NMR) spectroscopy to determine relative concentrations of organic functional groups. Houston aerosols are less oxidized than those observed elsewhere, with smaller relative contributions of carbon-oxygen double bonds. These particles do not fit 1H NMR source apportionment fingerprints for identification of secondary, marine, and biomass burning organic aerosol, suggesting that a new fingerprint for highly urbanized and industrially influenced locations be established.

Basics of Solar Heating & Hot Water Systems.

Science.gov (United States)

American Inst. of Architects, Washington, DC.

In presenting the basics of solar heating and hot water systems, this publication is organized from the general to the specific. It begins by presenting functional and operational descriptions of solar heating and domestic hot water systems, outlining the basic concepts and terminology. This is followed by a description of solar energy utilization…

East Asian Studies of Tropospheric Aerosols and their Impact on Regional Climate (EAST -AIRC): An overview

Science.gov (United States)

Zhangqing, Li; Li, C.; Chen, H.; Tsay, S.-C.; Holben, B.; Huang, J.; Li, B.; Maring, H.; Qian, Y.; Shi, G.;

Uptake of Alkylamines on Dicarboxylic Acids Relevant to Secondary Organic Aerosol Formation

Science.gov (United States)

Marrero-Ortiz, W.; Secrest, J.; Zhang, R.

2017-12-01

Aerosols play a critical role in climate directly by scattering and absorbing solar radiation, and indirectly by functioning as cloud condensation nuclei (CCN); both represent the largest uncertainties in climate predictions. New particle formation contributes significantly to CCN production; however, the mechanisms related to particle nucleation and growth processes are not well understood. Organic acids are atmospherically abundant, and their neutralization by low molecular weight amines may result in the formation of stable low volatility aminium salt products contributing to the growth of secondary organic aerosols and even the alteration of the aerosol properties. The acid-base neutralization of particle phase succinic acid and tartaric acid by low molecular weight aliphatic amines, i.e. methylamine, dimethylamine, and trimethylamine, has been investigated by employing a low-pressure fast flow reactor at 298K with an ion drift - chemical ionization mass spectrometer (ID-CIMS). The heterogeneous uptake is time dependent and influenced by organic acids functionality, alkylamines basicity, and steric effect. The implications of our results to atmospheric nanoparticle growth will be discussed.

The Java Series: Basic Concepts in Object Oriented Programming

CERN Multimedia

CERN. Geneva

2000-01-01

The talk will be general enough not to require any previous knowledge of any programming language but some insight in software development would be convenient. In the same way, the talk will give you the basics to learn any OO based methodology or language.

The Extended Enterprise concept

DEFF Research Database (Denmark)

Larsen, Lars Bjørn; Vesterager, Johan; Gobbi, Chiara

1999-01-01

This paper provides an overview of the work that has been done regarding the Extended Enterprise concept in the Common Concept team of Globeman 21 including references to results deliverables concerning the development of the Extended Enterprise concept. The first section presents the basic concept...... picture from Globeman21, which illustrates the Globeman21 way of realising the Extended Enterprise concept. The second section presents the Globeman21 EE concept in a life cycle perspective, which to a large extent is based on the thoughts and ideas behind GERAM (ISO/DIS 15704)....

Astronomy: a proposal to promote meaningful learning of basic concepts of Astronomy in the shaping of teachers of High School Education

Directory of Open Access Journals (Sweden)

Luiz Marcelo Darroz

2013-04-01

Full Text Available One presents, in this article, the process of drawing up and developing a didactic proposal about basic concepts of Astronomy. This proposal, which sought to build an educational path for the occurrence of significant learning of the concepts covered, was developed under an extension course to a group of 13 students graduating from teacher training in High School of a public school in Passo Fundo, Rio Grande do Sul. Initially one has developed the teaching methodology following from the Theory of Meaningful Learning Conceptions. The traces of meaningful learning have been obtained by means of instruments of research and evaluation, such as conceptual maps and role playing of the studied contents where the students transposed the approached subjects into new contexts. The obtained results from the learning questionnaires reached a high rate of hits. Through the registries of the meetings and the representations by drawings of the concepts, one has noticed that the students have genuinely understood the approached subjects. Through the conceptual maps the students were able to establish a progressive differentiation and an integrative reconciliation of the concepts. Thus, it was concluded that a methodology that takes into consideration what the student already knows it is essential to develop the joy of Science, the construction of meaning and appreciation of what is being learned.

Aerosol Indices Derived from MODIS Data for Indicating Aerosol-Induced Air Pollution

Directory of Open Access Journals (Sweden)

Junliang He

2014-02-01

Full Text Available Aerosol optical depth (AOD is a critical variable in estimating aerosol concentration in the atmosphere, evaluating severity of atmospheric pollution, and studying their impact on climate. With the assistance of the 6S radiative transfer model, we simulated apparent reflectancein relation to AOD in each Moderate Resolution Imaging Spectroradiometer (MODIS waveband in this study. The closeness of the relationship was used to identify the most and least sensitive MODIS wavebands. These two bands were then used to construct three aerosol indices (difference, ratio, and normalized difference for estimating AOD quickly and effectively. The three indices were correlated, respectively, with in situ measured AOD at the Aerosol Robotic NETwork (AERONET Lake Taihu, Beijing, and Xianghe stations. It is found that apparent reflectance of the blue waveband (band 3 is the most sensitive to AOD while the mid-infrared wavelength (band 7 is the least sensitive. The difference aerosol index is the most accurate in indicating aerosol-induced atmospheric pollution with a correlation coefficient of 0.585, 0.860, 0.685, and 0.333 at the Lake Taihu station, 0.721, 0.839, 0.795, and 0.629 at the Beijing station, and 0.778, 0.782, 0.837, and 0.643 at the Xianghe station in spring, summer, autumn and winter, respectively. It is concluded that the newly proposed difference aerosol index can be used effectively to study the level of aerosol-induced air pollution from MODIS satellite imagery with relative ease.

Observational evidence for the aerosol impact on ice cloud properties regulated by cloud/aerosol types

Science.gov (United States)

Zhao, B.; Gu, Y.; Liou, K. N.; Jiang, J. H.; Li, Q.; Liu, X.; Huang, L.; Wang, Y.; Su, H.

2017-12-01

The interactions between aerosols and ice clouds (consisting only of ice) represent one of the largest uncertainties in global radiative forcing from pre-industrial time to the present. The observational evidence for the aerosol impact on ice cloud properties has been quite limited and showed conflicting results, partly because previous observational studies did not consider the distinct features of different ice cloud and aerosol types. Using 9-year satellite observations, we find that, for ice clouds generated from deep convection, cloud thickness, cloud optical thickness (COT), and ice cloud fraction increase and decrease with small-to-moderate and high aerosol loadings, respectively. For in-situ formed ice clouds, however, the preceding cloud properties increase monotonically and more sharply with aerosol loadings. The case is more complicated for ice crystal effective radius (Rei). For both convection-generated and in-situ ice clouds, the responses of Rei to aerosol loadings are modulated by water vapor amount in conjunction with several other meteorological parameters, but the sensitivities of Rei to aerosols under the same water vapor amount differ remarkably between the two ice cloud types. As a result, overall Rei slightly increases with aerosol loading for convection-generated ice clouds, but decreases for in-situ ice clouds. When aerosols are decomposed into different types, an increase in the loading of smoke aerosols generally leads to a decrease in COT of convection-generated ice clouds, while the reverse is true for dust and anthropogenic pollution. In contrast, an increase in the loading of any aerosol type can significantly enhance COT of in-situ ice clouds. The modulation of the aerosol impacts by cloud/aerosol types is demonstrated and reproduced by simulations using the Weather Research and Forecasting (WRF) model. Adequate and accurate representations of the impact of different cloud/aerosol types in climate models are crucial for reducing the

Basic standards for radiation protection

International Nuclear Information System (INIS)

Webb, G.A.M.

1982-01-01

The basic standards for radiation protection have been based, for many years, on the recommendations of the International Commission of Radiological Protection. The three basic standards recommended by the Commission may be summarized as ''justification, optimization of protection and adherence to dose limitations. The applications of these basic principles to different aspects of protection are briefly summarized and the particular ways in which they have been applied to waste described in more detail. The application of dose limits, both in the control of occupational exposure and in regulating routine discharges of radioactive effluents is straight forward in principle although the measurement and calculational requirements may be substantial. Secondary standards such as derived limits may be extremely useful and the principles underlying their derivation will be described. Optimization of protection is inherently a more difficult concept to apply in protection and the various techniques used will be outlined by with particular emphasis on the use of cost benefit analysis are recommended by the ICRP. A review will be given of the problems involved in extending these basic concepts of the ICRP to probabilistic analyses such as those required for assessing the consequences of accidents or disruptive events in long term repositories. The particular difficulties posed by the very long timescales involved in the assessment of waste management practices will be discussed in some detail. (orig./RW)

How important is organic aerosol hygroscopicity to aerosol indirect forcing?

International Nuclear Information System (INIS)

Liu Xiaohong; Wang Jian

2010-01-01

Organics are among the most abundant aerosol components in the atmosphere. However, there are still large uncertainties with emissions of primary organic aerosol (POA) and volatile organic compounds (VOCs) (precursor gases of secondary organic aerosol, SOA), formation of SOA, and chemical and physical properties (e.g., hygroscopicity) of POA and SOA. All these may have significant impacts on aerosol direct and indirect forcing estimated from global models. In this study a modal aerosol module (MAM) in the NCAR community atmospheric model (CAM) is used to examine sensitivities of aerosol indirect forcing to hygroscopicity (represented by a single parameter 'κ' ) of POA and SOA. Our model simulation indicates that in the present-day (PD) condition changing the 'κ' value of POA from 0 to 0.1 increases the number concentration of cloud condensational nuclei (CCN) at supersaturation S = 0.1% by 40-80% over the POA source regions, while changing the 'κ' value of SOA by ± 50% (from 0.14 to 0.07 and 0.21) changes the CCN concentration within 40%. There are disproportionally larger changes in CCN concentration in the pre-industrial (PI) condition. Due to the stronger impact of organics hygroscopicity on CCN and cloud droplet number concentration at PI condition, global annual mean anthropogenic aerosol indirect forcing (AIF) between PD and PI conditions reduces with the increase of the hygroscopicity of organics. Global annual mean AIF varies by 0.4 W m -2 in the sensitivity runs with the control run of - 1.3 W m -2 , highlighting the need for improved understanding of organics hygroscopicity and its representation in global models.

Concept theory

DEFF Research Database (Denmark)

Hjørland, Birger

2009-01-01

  Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

Containment aerosol behaviour simulation studies in the BARC nuclear aerosol test facility

International Nuclear Information System (INIS)

Mayya, Y.S.; Sapra, B.K.; Khan, Arshad; Sunny, Faby; Nair, R.N.; Raghunath, Radha; Tripathi, R.M.; Markandeya, S.G.; Puranik, V.D.; Ghosh, A.K.; Kushwaha, H.S.; Shreekumar, K.P.; Padmanabhan, P.V.A.; Murthy, P.S.S.; Venlataramani, N.

2005-02-01

A Nuclear Aerosol Test Facility (NATF) has been built and commissioned at Bhabha Atomic Research Centre to carry out simulation studies on the behaviour of aerosols released into the reactor containment under accident conditions. This report also discusses some new experimental techniques for estimation of density of metallic aggregates. The experimental studies have shown that the dynamic densities of aerosol aggregates are far lower than their material densities as expected by the well-known fractal theory of aggregates. In the context of codes, this has significant bearing in providing a mechanistic basis for the input density parameter used in estimating the aerosol evolution characteristics. The data generated under the quiescent and turbulent conditions and the information on aggregate densities are now being subjected to the validation of the aerosol behaviour codes. (author)

Basic concepts in marine biology and ecology

International Nuclear Information System (INIS)

Small, L.F.

1997-01-01

An introduction to the marine biota, and how the biota interact with their physico-chemical environment, is given in this chapter. In particular, food web and trophic level relationships are discussed, from phytopIankton production through consumer organisms and the ''microbial loop''. The effects of organism size and functional relationships within the food web paradigm are emphasized, rather than taxonomic relationships. Examples initially given in terms of carbon, nitrogen, or energy transfer through food webs are placed in context with radionuclide transfer and the concept of biomagnification. (author)

Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

International Nuclear Information System (INIS)

Kanai, Taizo; Furuya, Masahiro; Arai, Takahiro; Nishi, Yoshihisa

2016-01-01

Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

Energy Technology Data Exchange (ETDEWEB)

Kanai, Taizo, E-mail: t-kanai@criepi.denken.or.jp; Furuya, Masahiro, E-mail: furuya@criepi.denken.or.jp; Arai, Takahiro, E-mail: t-arai@criepi.denken.or.jp; Nishi, Yoshihisa, E-mail: y-nishi@criepi.denken.or.jp

2016-07-15

Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

Basic physics for all

CERN Document Server

Kumar, B N

2012-01-01

This is a simple, concise book for both student and non-physics students, presenting basic facts in straightforward form and conveying fundamental principles and theories of physics. This book will be helpful as a supplement to class teaching and to aid those who have difficulty in mastering concepts and principles.

DARE : Dedicated Aerosols Retrieval Experiment

NARCIS (Netherlands)

Smorenburg, K.; Courrèges-Lacoste, G.B.; Decae, R.; Court, A.J.; Leeuw, G. de; Visser, H.

2004-01-01

At present there is an increasing interest in remote sensing of aerosols from space because of the large impact of aerosols on climate, earth observation and health. TNO has performed a study aimed at improving aerosol characterisation using a space based instrument and state-of-the-art aerosol

Filter-based Aerosol Measurement Experiments using Spherical Aerosol Particles under High Temperature and High Pressure

Energy Technology Data Exchange (ETDEWEB)

Lee, Jong Chan; Jung, Woo Young; Lee, Hyun Chul; Lee, Doo Young [FNC TECH., Yongin (Korea, Republic of)

2016-05-15

Optical Particle Counter (OPC) is used to provide real-time measurement of aerosol concentration and size distribution. Glass fiber membrane filter also be used to measure average mass concentration. Three tests (MTA-1, 2 and 3) have been conducted to study thermal-hydraulic effect, a filtering tendency at given SiO{sub 2} particles. Based on the experimental results, the experiment will be carried out further with a main carrier gas of steam and different aerosol size. The test results will provide representative behavior of the aerosols under various conditions. The aim of the tests, MTA 1, 2 and 3, are to be able to 1) establish the test manuals for aerosol generation, mixing, sampling and measurement system, which defines aerosol preparation, calibration, operating and evaluation method under high pressure and high temperature 2) develop commercial aerosol test modules applicable to the thermal power plant, environmental industry, automobile exhaust gas, chemical plant, HVAC system including nuclear power plant. Based on the test results, sampled aerosol particles in the filter indicate that important parameters affecting aerosol behavior aerosols are 1) system temperature to keep above a evaporation temperature of ethanol and 2) aerosol losses due to the settling by ethanol liquid droplet.

Aerosol Chemical Composition and its Effects on Cloud-Aerosol Interactions during the 2007 CHAPS Experiment

Science.gov (United States)

Lee, Y.; Alexander, L.; Newburn, M.; Jayne, J.; Hubbe, J.; Springston, S.; Senum, G.; Andrews, B.; Ogren, J.; Kleinman, L.; Daum, P.; Berg, L.; Berkowitz, C.

2007-12-01

Chemical composition of submicron aerosol particles was determined using an Aerodyne Time-of-Flight Aerosol Mass Spectrometer (AMS) outfitted on the DOE G-1 aircraft during the Cumulus Humilis Aerosol Processing Study (CHAPS) conducted in Oklahoma City area in June 2007. The primary objective of CHAPS was to investigate the effects of urban emissions on cloud aerosol interactions as a function of processing of the emissions. Aerosol composition was typically determined at three different altitudes: below, in, and above cloud, in both upwind and downwind regions of the urban area. Aerosols were sampled from an isokinetic inlet with an upper size cut-off of ~1.5 micrometer. During cloud passages, the AMS also sampled particles that were dried from cloud droplets collected using a counter-flow virtual impactor (CVI) sampler. The aerosol mass concentrations were typically below 10 microgram per cubic meter, and were dominated by organics and sulfate. Ammonium was often less than required for complete neutralization of sulfate. Aerosol nitrate levels were very low. We noted that nitrate levels were significantly enhanced in cloud droplets compared to aerosols, most likely resulting from dissolution of gaseous nitric acid. Organic to sulfate ratios appeared to be lower in cloud droplets than in aerosols, suggesting cloud condensation nuclei properties of aerosol particles might be affected by loading and nature of the organic components in aerosols. In-cloud formation of sulfate was considered unimportant because of the very low SO2 concentration in the region. A detailed examination of the sources of the aerosol organic components (based on hydrocarbons determined using a proton transfer reaction mass spectrometer) and their effects on cloud formation as a function of atmospheric processing (based on the degree of oxidation of the organic components) will be presented.

Water content of aged aerosol

OpenAIRE

G. J. Engelhart; L. Hildebrandt; E. Kostenidou; N. Mihalopoulos; N. M. Donahue; S. N. Pandis

2010-01-01

The composition and physical properties of aged atmospheric aerosol were characterized at a remote sampling site on the northern coast of Crete, Greece during the Finokalia Aerosol Measurement Experiment in May 2008 (FAME-2008). A reduced Dry-Ambient Aerosol Size Spectrometer (DAASS) was deployed to measure the aerosol water content and volumetric growth factor of fine particulate matter. The particles remained wet even at relative humidity (RH) as low as 20%. The aerosol was acidic during mo...

Aerosol effects on UV radiation

International Nuclear Information System (INIS)

Koepke, P.; Reuder, J.; Schwander, H.

2000-01-01

The reduction of erythemally weighted UV-irradiance (given as UV index, UVI) due to aerosols is analyzed by variation of the tropospheric particles in a wide, but realistic range. Varied are amount and composition of the particles and relative humidity and thickness of the mixing layer. The reduction of UVI increases with aerosol optical depth and the UV change is around 10% for a change aerosol optical depth from 0.25 to 0.1 and 0.4 respectively. Since both aerosol absorption and scattering are of relevance, the aerosol effect depends besides total aerosol amount on relative amount of soot and on relative humidity

Aerosol sampler for analysis of fine and ultrafine aerosols

Czech Academy of Sciences Publication Activity Database

Mikuška, Pavel; Čapka, Lukáš; Večeřa, Zbyněk

2018-01-01

Roč. 1020 (2018), s. 123-133 ISSN 0003-2670 R&D Projects: GA ČR(CZ) GA14-25558S Institutional support: RVO:68081715 Keywords : atmospheric aerosols * aerosol collection * chemical composition Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 4.950, year: 2016

Aerosol retrieval algorithm for the characterization of local aerosol using MODIS L1B data

International Nuclear Information System (INIS)

Wahab, A M; Sarker, M L R

2014-01-01

Atmospheric aerosol plays an important role in radiation budget, climate change, hydrology and visibility. However, it has immense effect on the air quality, especially in densely populated areas where high concentration of aerosol is associated with premature death and the decrease of life expectancy. Therefore, an accurate estimation of aerosol with spatial distribution is essential, and satellite data has increasingly been used to estimate aerosol optical depth (AOD). Aerosol product (AOD) from Moderate Resolution Imaging Spectroradiometer (MODIS) data is available at global scale but problems arise due to low spatial resolution, time-lag availability of AOD product as well as the use of generalized aerosol models in retrieval algorithm instead of local aerosol models. This study focuses on the aerosol retrieval algorithm for the characterization of local aerosol in Hong Kong for a long period of time (2006-2011) using high spatial resolution MODIS level 1B data (500 m resolution) and taking into account the local aerosol models. Two methods (dark dense vegetation and MODIS land surface reflectance product) were used for the estimation of the surface reflectance over land and Santa Barbara DISORT Radiative Transfer (SBDART) code was used to construct LUTs for calculating the aerosol reflectance as a function of AOD. Results indicate that AOD can be estimated at the local scale from high resolution MODIS data, and the obtained accuracy (ca. 87%) is very much comparable with the accuracy obtained from other studies (80%-95%) for AOD estimation

Comprehensive Measurement of Atmospheric Aerosols with a Wide Range Aerosol Spectrometer

International Nuclear Information System (INIS)

Keck, L; Pesch, M; Grimm, H

2011-01-01

A wide range aerosol spectrometer (WRAS) was used for comprehensive long term measurements of aerosol size distributions. The system combines the results of an optical aerosol spectrometer with the results of a Scanning Mobility Particle Sizer (SMPS) to record essentially the full size range (5 nm - 32 μm) of atmospheric particles in 72 channels. Measurements were carried out over one year (2009) at the Global Atmospheric Watch (GAW)-Station Hohenpeissenberg, Bavaria. Total particle number concentrations obtained from the aerosol size distributions were compared to the total number concentrations measured by a Condensation Particle Counter (CPC). The comparison showed an excellent agreement of the data. The high time resolution of 5 minutes allows the combination of the measured size distributions with meteorological data and correlations to gaseous pollutants (CO, NOx and SO2). A good correlation of particle number and CO concentrations was found for long distance transported small particles, which were probably mainly soot particles. Correlations to NOx were observed for aerosols from local sources such as traffic emissions. The formation of secondary aerosols from gaseous precursors was also observed. Episodes of relatively high concentration of particles in the range of 2-3 μm were probably caused by pollen.

The DRAGON aerosol research facility to study aerosol behaviour for reactor safety applications

International Nuclear Information System (INIS)

Suckow, Detlef; Guentay, Salih

2008-01-01

During a severe accident in a nuclear power plant fission products are expected to be released in form of aerosol particles and droplets. To study the behaviour of safety relevant reactor components under aerosol loads and prototypical severe accident conditions the multi-purpose aerosol generation facility DRAGON is used since 1994 for several projects. DRAGON can generate aerosol particles by the evaporation-condensation technique using a plasma torch system, fluidized bed and atomization of particles suspended in a liquid. Soluble, hygroscopic aerosol (i.e. CsOH) and insoluble aerosol particles (i.e. SnO 2 , TiO 2 ) or mixtures of them can be used. DRAGON uses state-of-the-art thermal-hydraulic, data acquisition and aerosol measurement techniques and is mainly composed of a mixing chamber, the plasma torch system, a steam generator, nitrogen gas and compressed air delivery systems, several aerosol delivery piping, gas heaters and several auxiliary systems to provide vacuum, coolant and off-gas treatment. The facility can be operated at system pressure of 5 bars, temperatures of 300 deg. C, flow rates of non-condensable gas of 900 kg/h and steam of 270 kg/h, respectively. A test section under investigation is attached to DRAGON. The paper summarizes and demonstrates with the help of two project examples the capabilities of DRAGON for reactor safety studies. (authors)

Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

Energy Technology Data Exchange (ETDEWEB)

Richard A. Ferrare; David D. Turner

2011-09-01

Project goals: (1) Use the routine surface and airborne measurements at the ARM SGP site, and the routine surface measurements at the NSA site, to continue our evaluations of model aerosol simulations; (2) Determine the degree to which the Raman lidar measurements of water vapor and aerosol scattering and extinction can be used to remotely characterize the aerosol humidification factor; (3) Use the high temporal resolution CARL data to examine how aerosol properties vary near clouds; and (4) Use the high temporal resolution CARL and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds.

Aerosols CFA 97

International Nuclear Information System (INIS)

Anon.

1998-01-01

During the thirteen congress on aerosols several papers were presented about the behaviour of radioactive aerosols and their impact on environment, or the exposure to radon and to its daughters, the measurement of the size of the particulates of the short-lived radon daughters and two papers about the behaviour of aerosols in containment during a fission products release in the primary circuit and susceptible to be released in atmosphere in the case of containment failure. (N.C.)

Health as a basic human need: would this be enough?

Science.gov (United States)

de Campos, Thana Cristina

2012-01-01

Although the value of health is universally agreed upon, its definition is not. Both the WHO and the UN define health in terms of well-being. They advocate a globally shared responsibility that all of us - states, international organizations, pharmaceutical corporations, civil society, and individuals - bear for the health (that is, the well-being) of the world's population. In this paper I argue that this current well-being conception of health is troublesome. Its problem resides precisely in the fact that the well-being conception of health, as an all-encompassing label, does not properly distinguish between the different realities of health and the different demands of justice, which arise in each case. In addressing responsibilities related to the right to health, we need to work with a more differentiated vocabulary, which can account for these different realities. A crucial distinction to bear in mind, for the purposes of moral deliberation and the crafting of political and legal institutions, is the difference between basic and non-basic health needs. This distinction is crucial because we have presumably more stringent obligations and rights in relation to human needs that are basic, as they justify stronger moral claims, than those grounded on non-basic human needs. It is important to keep this moral distinction in mind because many of the world's problems regarding the right to health relate to basic health needs. By conflating these needs with less essential ones, we risk confusing different types of moral claims and weakening the overall case for establishing duties regarding the right to health. There is, therefore, a practical need to reevaluate the current normative conception of health so that it distinguishes, within the broad scope of well-being, between what is basic and what is not. My aim here is to shed light onto this distinction and to show the need for this differentiation. I do so, first, by providing, on the basis of David Miller

A multi-crucible core-catcher concept: Design considerations and basic results

International Nuclear Information System (INIS)

Szabo, I.

1995-01-01

A multi-crucible core-catcher concept to be implemented in new light water reactor containments has recently been proposed. This paper deals with conceptual design considerations and the various ways this type of core-catcher could be designed to meet requirements for reactor application. A systematic functional analysis of the multi-crucible core-catcher concept and the results of the preliminary design calculation are presented. Finally, the adequacy of the multi-crucible core-catcher concept for reactor application is discussed. (orig.)

The ion–aerosol interactions from the ion mobility and aerosol ...

Indian Academy of Sciences (India)

2005-02-18

aerosol interactions from the ion mobility and aerosol particle size distribution measurements on January 17 and February 18, 2005 at Maitri, Antarctica – A case study. Devendraa Siingh Vimlesh Pant A K Kamra. Volume 120 Issue 4 August ...

Parameters influencing the aerosol capture performance of the Submerged-Bed Scrubber

International Nuclear Information System (INIS)

Ruecker, C.M.; Scott, P.A.

1987-04-01

The Submerged-Bed Scrubber (SBS) is a novel air cleaning device that has been investigated by Pacific Northwest Laboratory (PNL) for scrubbing off gases from liquid-fed ceramic melters used to vitrify high-level waste (HLW). The concept for the SBS was originally conceived at Hanford for emergency venting of a reactor containment building. The SBS was adapted for use as a quenching scrubber at PNL because it can cool the hot melter off gas as well as remove over 90% of the airborne particles, thus meeting the minimum particulate decontamination factor (DF) of 10 required of a primary scrubber. The experiments in this study showed that the submicron aerosol DF for the SBS can exceed 100 under certain conditions. A conventional device, the ejector-venturi scrubber (EVS), has been previously used in this application. The EVS also adequately cools the hot gases from the melter while exhibiting aerosol removal DFs in the range of 5 to 30. In addition to achieving higher DFs than the EVS, however, the SBS has the advantage of being a passive system, better suited to the remote environment of an HLW processing system. The objective of this study was to characterize the performance of the SBS and to improve the aerosol capture efficiency by modifying the operating procedure or the design. A partial factorial experimental matrix was completed to determine the main effects of aerosol solubility, inlet off-gas temperature, inlet off-gas flow rate, steam-to-air ratio, bed diameter and packing diameter on the particulate removal efficiency of the SBS. Several additional experiments were conducted to measure the influence of the inlet aerosol concentration and scrubbing-water concentration on aerosol-removal performance. 33 refs., 17 figs., 14 tabs

Conceptions of health service robots

DEFF Research Database (Denmark)

Lystbæk, Christian Tang

2015-01-01

Technology developments create rich opportunities for health service providers to introduce service robots in health care. While the potential benefits of applying robots in health care are extensive, the research into the conceptions of health service robot and its importance for the uptake...... of robotics technology in health care is limited. This article develops a model of the basic conceptions of health service robots that can be used to understand different assumptions and values attached to health care technology in general and health service robots in particular. The article takes...... a discursive approach in order to develop a conceptual framework for understanding the social values of health service robots. First a discursive approach is proposed to develop a typology of conceptions of health service robots. Second, a model identifying four basic conceptions of health service robots...

Aerosol Observing System (AOS) Handbook

Energy Technology Data Exchange (ETDEWEB)

Jefferson, A

2011-01-17

The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

Teaching the basic concepts of the Special Relativity in the secondary school in the framework of the Theory of Conceptual Fields of Vergnaud

Science.gov (United States)

Rita Otero, Marıa; Arlego, Marcelo; Prodanoff, Fabiana

2016-05-01

In this work, we investigate the conceptualization of the basic aspects of Special Relativity (SR) at secondary school level. We have conducted our research along the lines of the Theory of Conceptual Fields (TCF) proposed by Vergnaud (Vergnaud G., Infancia y Aprendizaje, 36 (2013) 131). The investigation consisted in the design, implementation and evaluation of a didactic sequence specially elaborated to conceptualize the basic aspects of SR. The proposal is composed by eight situations, complemented with a set of exercises. It was carried out in two classrooms with students of the last year of secondary level (17years old, N = 43 . The conceptualization was analyzed in a classroom context, where the selected situations are essential to promote the emergence of the relevant concepts.

Teaching the basic concepts of the Special Relativity in the secondary school in the framework of the Theory of Conceptual Fields of Vergnaud

International Nuclear Information System (INIS)

Otero, Maria Rira; Arlego, Marcelo; Prodanoff, F.

2015-01-01

In this work, we investigate the conceptualization of the basic aspects of Special Relativity (SR) at secondary school level. We have conducted our research along the lines of the Theory of Conceptual Fields (TCF) proposed by Vergnaud (Vergnaud G., Infancia y Aprendizaje, 36 (2013) 131). The investigation consisted in the design, implementation and evaluation of a didactic sequence specially elaborated to conceptualize the basic aspects of SR. The proposal is composed by eight situations, complemented with a set of exercises. It was carried out in two classrooms with students of the last year of secondary level (17 years old, N = 43). The conceptualization was analyzed in a classroom context, where the selected situations are essential to promote the emergence of the relevant concepts.

Basic of X-ray diffraction

International Nuclear Information System (INIS)

Giacovazzo, C.

1996-01-01

The basic concepts of X-ray diffraction may be more easily understood if it is made preliminary use of a mathematical background. In these pages the authors will first define the delta function and its use for the representation of a lattice. Then the concepts of Fourier transform and convolution are given. At the end of this talk one should realize that a crystal is the convolution of the lattice with a function representing the content of the unit cell

Basic of X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Giacovazzo, C [Bari Univ. (Italy). Dip. Geomineralogico

1996-09-01

The basic concepts of X-ray diffraction may be more easily understood if it is made preliminary use of a mathematical background. In these pages the authors will first define the delta function and its use for the representation of a lattice. Then the concepts of Fourier transform and convolution are given. At the end of this talk one should realize that a crystal is the convolution of the lattice with a function representing the content of the unit cell.

Basic statistics for social research

CERN Document Server

Hanneman, Robert A; Riddle, Mark D

2012-01-01

A core statistics text that emphasizes logical inquiry, notmath Basic Statistics for Social Research teaches core generalstatistical concepts and methods that all social science majorsmust master to understand (and do) social research. Its use ofmathematics and theory are deliberately limited, as the authorsfocus on the use of concepts and tools of statistics in theanalysis of social science data, rather than on the mathematicaland computational aspects. Research questions and applications aretaken from a wide variety of subfields in sociology, and eachchapter is organized arou

Giant Magnetoresistance: Basic Concepts, Microstructure, Magnetic Interactions and Applications.

Science.gov (United States)

Ennen, Inga; Kappe, Daniel; Rempel, Thomas; Glenske, Claudia; Hütten, Andreas

2016-06-17

The giant magnetoresistance (GMR) effect is a very basic phenomenon that occurs in magnetic materials ranging from nanoparticles over multilayered thin films to permanent magnets. In this contribution, we first focus on the links between effect characteristic and underlying microstructure. Thereafter, we discuss design criteria for GMR-sensor applications covering automotive, biosensors as well as nanoparticular sensors.

Basic radiation oncology

International Nuclear Information System (INIS)

Beyzadeoglu, M. M.; Ebruli, C.

2008-01-01

Basic Radiation Oncology is an all-in-one book. It is an up-to-date bedside oriented book integrating the radiation physics, radiobiology and clinical radiation oncology. It includes the essentials of all aspects of radiation oncology with more than 300 practical illustrations, black and white and color figures. The layout and presentation is very practical and enriched with many pearl boxes. Key studies particularly randomized ones are also included at the end of each clinical chapter. Basic knowledge of all high-tech radiation teletherapy units such as tomotherapy, cyberknife, and proton therapy are also given. The first 2 sections review concepts that are crucial in radiation physics and radiobiology. The remaining 11 chapters describe treatment regimens for main cancer sites and tumor types. Basic Radiation Oncology will greatly help meeting the needs for a practical and bedside oriented oncology book for residents, fellows, and clinicians of Radiation, Medical and Surgical Oncology as well as medical students, physicians and medical physicists interested in Clinical Oncology. English Edition of the book Temel Radyasyon Onkolojisi is being published by Springer Heidelberg this year with updated 2009 AJCC Staging as Basic Radiation Oncology

Aerosol-foam interaction experiments

International Nuclear Information System (INIS)

Ball, M.H.E.; Luscombe, C.DeM.; Mitchell, J.P.

1990-03-01

Foam treatment offers the potential to clean gas streams containing radioactive particles. A large decontamination factor has been claimed for the removal of airborne plutonium dust when spraying a commercially available foam on the walls and horizontal surfaces of an alpha-active room. Experiments have been designed and undertaken to reproduce these conditions with a non-radioactive simulant aerosol. Careful measurements of aerosol concentrations with and without foam treatment failed to provide convincing evidence to support the earlier observation. The foam may not have been as well mixed with the aerosol in the present studies. Further work is required to explore more efficient mixing methods, including systems in which the aerosol steam is passed through the foam, rather than merely spraying foam into the path of the aerosol. (author)

Arctic Aerosols and Sources

DEFF Research Database (Denmark)

Nielsen, Ingeborg Elbæk

2017-01-01

Since the Industrial Revolution, the anthropogenic emission of greenhouse gases has been increasing, leading to a rise in the global temperature. Particularly in the Arctic, climate change is having serious impact where the average temperature has increased almost twice as much as the global during......, ammonium, black carbon, and trace metals. This PhD dissertation studies Arctic aerosols and their sources, with special focus on black carbon, attempting to increase the knowledge about aerosols’ effect on the climate in an Arctic content. The first part of the dissertation examines the diversity...... of aerosol emissions from an important anthropogenic aerosol source: residential wood combustion. The second part, characterizes the chemical and physical composition of aerosols while investigating sources of aerosols in the Arctic. The main instrument used in this research has been the state...

The Impact of Aerosol Particle Mixing State on the Hygroscopicity of Sea Spray Aerosol.

Science.gov (United States)

Schill, Steven R; Collins, Douglas B; Lee, Christopher; Morris, Holly S; Novak, Gordon A; Prather, Kimberly A; Quinn, Patricia K; Sultana, Camille M; Tivanski, Alexei V; Zimmermann, Kathryn; Cappa, Christopher D; Bertram, Timothy H

2015-06-24

Aerosol particles influence global climate by determining cloud droplet number concentrations, brightness, and lifetime. Primary aerosol particles, such as those produced from breaking waves in the ocean, display large particle-particle variability in chemical composition, morphology, and physical phase state, all of which affect the ability of individual particles to accommodate water and grow into cloud droplets. Despite such diversity in molecular composition, there is a paucity of methods available to assess how particle-particle variability in chemistry translates to corresponding differences in aerosol hygroscopicity. Here, an approach has been developed that allows for characterization of the distribution of aerosol hygroscopicity within a chemically complex population of atmospheric particles. This methodology, when applied to the interpretation of nascent sea spray aerosol, provides a quantitative framework for connecting results obtained using molecular mimics generated in the laboratory with chemically complex ambient aerosol. We show that nascent sea spray aerosol, generated in situ in the Atlantic Ocean, displays a broad distribution of particle hygroscopicities, indicative of a correspondingly broad distribution of particle chemical compositions. Molecular mimics of sea spray aerosol organic material were used in the laboratory to assess the volume fractions and molecular functionality required to suppress sea spray aerosol hygroscopicity to the extent indicated by field observations. We show that proper accounting for the distribution and diversity in particle hygroscopicity and composition are important to the assessment of particle impacts on clouds and global climate.

Primary aerosol and secondary inorganic aerosol budget over the Mediterranean Basin during 2012 and 2013

Science.gov (United States)

Guth, Jonathan; Marécal, Virginie; Josse, Béatrice; Arteta, Joaquim; Hamer, Paul

2018-04-01

In the frame of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx), we analyse the budget of primary aerosols and secondary inorganic aerosols over the Mediterranean Basin during the years 2012 and 2013. To do this, we use two year-long numerical simulations with the chemistry-transport model MOCAGE validated against satellite- and ground-based measurements. The budget is presented on an annual and a monthly basis on a domain covering 29 to 47° N latitude and 10° W to 38° E longitude. The years 2012 and 2013 show similar seasonal variations. The desert dust is the main contributor to the annual aerosol burden in the Mediterranean region with a peak in spring, and sea salt being the second most important contributor. The secondary inorganic aerosols, taken as a whole, contribute a similar level to sea salt. The results show that all of the considered aerosol types, except for sea salt aerosols, experience net export out of our Mediterranean Basin model domain, and thus this area should be considered as a source region for aerosols globally. Our study showed that 11 % of the desert dust, 22.8 to 39.5 % of the carbonaceous aerosols, 35 % of the sulfate and 9 % of the ammonium emitted or produced into the study domain are exported. The main sources of variability for aerosols between 2012 and 2013 are weather-related variations, acting on emissions processes, and the episodic import of aerosols from North American fires. In order to assess the importance of the anthropogenic emissions of the marine and the coastal areas which are central for the economy of the Mediterranean Basin, we made a sensitivity test simulation. This simulation is similar to the reference simulation but with the removal of the international shipping emissions and the anthropogenic emissions over a 50 km wide band inland along the coast. We showed that around 30 % of the emissions of carbonaceous aerosols and 35 to 60 % of the exported carbonaceous aerosols originates from the marine and

191 Students' Self-Concept and Their Achievement in Basic Science ...

African Journals Online (AJOL)

User

2011-07-21

Jul 21, 2011 ... Achievement Test in Basic showed Science (SATBS) were employed as .... Higher Studies; Teacher-Students opinion and found out that students .... Factors and Pupils Leaning Outcome in Bended Primary Science Project,.

Stable generator of polydisperse aerosol

Czech Academy of Sciences Publication Activity Database

Mikuška, Pavel

2001-01-01

Roč. 32, Suppl. 1 (2001), s. S823-S824 ISSN 0021-8502. [European Aerosol Conference 2001. Leipzig, 03.09.2001-07.09.2001] R&D Projects: GA AV ČR IAA4031105 Institutional research plan: CEZ:AV0Z4031919 Keywords : aerosol generator * fine aerosol * polydisperse aerosol Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.605, year: 2001

Aerosol counterflow two-jets unit for continuous measurement of the soluble fraction of atmospheric aerosols.

Science.gov (United States)

Mikuska, Pavel; Vecera, Zbynek

2005-09-01

A new type of aerosol collector employing a liquid at laboratory temperature for continuous sampling of atmospheric particles is described. The collector operates on the principle of a Venturi scrubber. Sampled air flows at high linear velocity through two Venturi nozzles "atomizing" the liquid to form two jets of a polydisperse aerosol of fine droplets situated against each other. Counterflow jets of droplets collide, and within this process, the aerosol particles are captured into dispersed liquid. Under optimum conditions (air flow rate of 5 L/min and water flow rate of 2 mL/min), aerosol particles down to 0.3 microm in diameter are quantitatively collected in the collector into deionized water while the collection efficiency of smaller particles decreases. There is very little loss of fine aerosol within the aerosol counterflow two-jets unit (ACTJU). Coupling of the aerosol collector with an annular diffusion denuder located upstream of the collector ensures an artifact-free sampling of atmospheric aerosols. Operation of the ACTJU in combination with on-line detection devices allows in situ automated analysis of water-soluble aerosol species (e.g., NO2-, NO3-)with high time resolution (as high as 1 s). Under the optimum conditions, the limit of detection for particulate nitrite and nitrate is 28 and 77 ng/m(3), respectively. The instrument is sufficiently rugged for its application at routine monitoring of aerosol composition in the real time.

American Association for Aerosol Research (AAAR) `95

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The Fourteenth annual meeting of the American Association for Aerosol Research was held October 9-13, 1995 at Westin William Penn Hotel in Pittsburgh, PA. This volume contains the abstracts of the papers and poster sessions presented at this meeting, grouped by the session in which they were presented as follows: Radiation Effects; Aerosol Deposition; Collision Simulations and Microphysical Behavior; Filtration Theory and Measurements; Materials Synthesis; Radioactive and Nuclear Aerosols; Aerosol Formation, Thermodynamic Properties, and Behavior; Particle Contamination Issues in the Computer Industry; Pharmaceutical Aerosol Technology; Modeling Global/Regional Aerosols; Visibility; Respiratory Deposition; Biomass and Biogenic Aerosols; Aerosol Dynamics; Atmospheric Aerosols.

The Correlation Study of Interest at Physics and Knowledge of Mathematics Basic Concepts towards the Ability to Solve Physics Problems of 7th Grade Students at Junior High School in Ambon Maluku Province, Indonesia

Directory of Open Access Journals (Sweden)

Izaak Hendrik Wenno

2015-01-01

Full Text Available The purpose of the study is to determine the relation between interest at Physics and knowledge of Mathematics basic concepts with the ability to solve Physics problems. The populations are all students in the 7th grade at the junior high school in Ambon, Maluku, Indonesia. The used sample schools are Junior High Schools 8, 9, and 10 during 2013/2014 academic year with 44 students per school. Two independent variables and one dependent variable are studied. The independent variables are the interest at Physics (X1 and the knowledge of Mathematics basic concepts (X2, while the dependent variable is the ability to solve Physics problems (Y. Data collection technique for X1 is an interview with questionnaire instrument, while for the X2 and Y is using the test technique with test items instrument. The obtained data from the measurements were analyzed with descriptive analysis and inferential analysis. The results show that there is a positive relation between interest at Physics and knowledge of Mathematics basic concepts with students’ ability to solve Physics problems.

Size distributions of aerosols produced from substitute materials by the Laskin cold DOP aerosol generator

International Nuclear Information System (INIS)

Hinds, W.; Macher, J.; First, M.W.

1981-01-01

Test aerosols of di(2-ethylhexyl)phthalate (DOP) produced by Laskin nozzle aerosol generators are widely used for in-place filter testing and respirator fit testing. Concern for the health effects of this material has led to a search for substitute materials for test aerosols. Aerosols were generated with a Laskin generator and diluted 6000-fold with clean air. Size distributions were measured for DOP, di(2-ethylhexyl)sebecate, polyethylene glycol, mineral oil, and corn oil aerosols with a PMS ASAS-X optical particle counter. Distributions were slightly bimodal with count median diameters from 0.22 to 0.30 μm. Size distributions varied little with aerosol material, operating pressure, or liquid level. Mineral oil and corn oil gave the best agreement with the DOP size distribution

Aerosol effects in radiation transfer

International Nuclear Information System (INIS)

Binenko, V.I.; Harshvardhan, H.

1993-01-01

The radiative properties and effects of aerosols are assessed for the following aerosol sources: relatively clean background aerosol, dust storms and dust outbreaks, anthropogenic pollution, and polluted cloud layers. Studies show it is the submicron aerosol fraction that plays a dominant radiative role in the atmosphere. The radiative effect of the aerosol depends not only on its loading but also on the underlying surface albedo and on solar zenith angle. It is only with highly reflecting surfaces such as Arctic ice that aerosols have a warming effect. Radiometric, microphysical, mineral composition, and refractive index measurements are presented for dust and in particular for the Saharan aerosol layer (SAL). Short-wave radiative heating of the atmosphere is caused by the SAL and is due mainly to absorption. However, the SAL does not contribute significantly to the long-wave thermal radiation budget. Field program studies of the radiative effects of aerosols are described. Anthropogenic aerosols deplete the incoming solar radiation. A case field study for a regional Ukrainian center is discussed. The urban aerosol causes a cooling of metropolitan centers, compared with outlying areas, during the day, which is followed by a warming trend at night. In another study, an increase in turbidity by a factor of 3 due to increased industrialization for Mexico City is noted, together with a drop in atmospheric transmission by 10% over a 50-year period. Numerous studies are cited that demonstrate that anthropogenic aerosols affect both the microphysical and radiative properties of clouds, which in turn affect regional climate. Particles acting as cloud nuclei are considered to have the greatest indirect effect on cloud absorptivity of short-wave radiation. Satellite observations show that low-level stratus clouds contaminated by ship exhaust at sea lead to an increase in cloud albedo

Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment – 2008

Directory of Open Access Journals (Sweden)

L. Hildebrandt

2010-05-01

Full Text Available Aged organic aerosol (OA was measured at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2008 (FAME-2008, which was part of the EUCAARI intensive campaign of May 2008. The site at Finokalia is influenced by air masses from different source regions, including long-range transport of pollution from continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS was employed to measure the size-resolved chemical composition of non-refractory submicron aerosol (NR-PM₁, and to estimate the extent of oxidation of the organic aerosol. Factor analysis was used to gain insights into the processes and sources affecting the OA composition. The particles were internally mixed and liquid. The largest fraction of the dry NR-PM₁ sampled was ammonium sulfate and ammonium bisulfate, followed by organics and a small amount of nitrate. The variability in OA composition could be explained with two factors of oxygenated organic aerosol (OOA with differing extents of oxidation but similar volatility. Hydrocarbon-like organic aerosol (HOA was not detected. There was no statistically significant diurnal variation in the bulk composition of NR-PM₁ such as total sulfate or total organic aerosol concentrations. However, the OA composition exhibited statistically significant diurnal variation with more oxidized OA in the afternoon. The organic aerosol was highly oxidized, regardless of the source region. Total OA concentrations also varied little with source region, suggesting that local sources had only a small effect on OA concentrations measured at Finokalia. The aerosol was transported for about one day before arriving at the site, corresponding to an OH exposure of approximately 4×10¹¹ molecules cm⁻³ s. The constant extent of oxidation suggests that atmospheric aging results in a highly oxidized OA at these OH exposures, regardless of the aerosol source.

The Efficacy of Multimedia Modules for Teaching Basic Literacy-Related Concepts

Science.gov (United States)

Sayeski, Kristin L.; Kennedy, Michael J.; de Irala, Sandra; Clinton, Elias; Hamel, Melissa; Thomas, Kristen

2015-01-01

Researchers have found that teacher preparation programs are not universally preparing teacher candidates in concepts associated with the alphabetic principle. Yet, the majority of students with reading disabilities or who struggle with beginning reading have difficulty with phonology and concepts associated with the alphabetic principle. The…

Revisiting the Basic Symptom Concept: Towards Translating Risk Symptoms for Psychosis into Neurobiological Targets

Directory of Open Access Journals (Sweden)

Frauke eSchultze-Lutter

2016-01-01

Full Text Available In its initial formulation, the concept of basic symptoms (BSs integrated findings on the early symptomatic course of schizophrenia and first in vivo evidence of accompanying brain aberrations. It argued that the subtle subclinical disturbances in mental processes described as BSs were the most direct self-experienced expression of the underlying neurobiological aberrations of the disease. Other characteristic symptoms of psychosis (e.g., delusions, hallucinations were conceptualized as secondary phenomena, resulting from dysfunctional beliefs and suboptimal coping styles with emerging BSs and/or concomitant stressors. While BSs can occur in many mental disorders, in particular affective disorders, a subset of perceptive and cognitive BSs appear to be specific to psychosis and are currently employed in two alternative risk criteria. However, despite their clinical recognition in the early detection of psychosis, neurobiological research on the aetiopathology of psychosis with neuroimaging methods has only just begun to consider the neural correlate of BSs. This perspective paper reviews the emerging evidence of an association between BSs and aberrant brain activation, connectivity patterns, and metabolism, and outlines promising routes for the use of BSs in aetiopathological research on psychosis.

Production of Highly Charged Pharmaceutical Aerosols Using a New Aerosol Induction Charger.

Science.gov (United States)

Golshahi, Laleh; Longest, P Worth; Holbrook, Landon; Snead, Jessica; Hindle, Michael

2015-09-01

Properly charged particles can be used for effective lung targeting of pharmaceutical aerosols. The objective of this study was to characterize the performance of a new induction charger that operates with a mesh nebulizer for the production of highly charged submicrometer aerosols to bypass the mouth-throat and deliver clinically relevant doses of medications to the lungs. Variables of interest included combinations of model drug (albuterol sulfate) and charging excipient (NaCl) as well as strength of the charging field (1-5 kV/cm). Aerosol charge and size were measured using a modified electrical low pressure impactor system combined with high performance liquid chromatography. At the approximate mass median aerodynamic diameter (MMAD) of the aerosol (~0.4 μm), the induction charge on the particles was an order of magnitude above the field and diffusion charge limit. The nebulization rate was 439.3 ± 42.9 μl/min, which with a 0.1% w/v solution delivered 419.5 ± 34.2 μg of medication per minute. A new correlation was developed to predict particle charge produced by the induction charger. The combination of the aerosol induction charger and predictive correlations will allow for the practical generation and control of charged submicrometer aerosols for targeting deposition within the lungs.

Amide proton transfer imaging in clinics: Basic concepts and current and future use in brain tumors and stoke

Energy Technology Data Exchange (ETDEWEB)

Park, Ji Eun [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Jahng, Geon Ho [Dept. of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Seoul (Korea, Republic of); Jeong, Ha Kyu [Philips Korea, Seoul (Korea, Republic of)

2016-12-15

Amide proton transfer (APT) imaging is gaining attention as a relatively new in vivo molecular imaging technique that has higher sensitivity and spatial resolution than magnetic resonance spectroscopy imaging. APT imaging is a subset of the chemical exchange saturation transfer mechanism, which can offer unique image contrast by selectively saturating protons in target molecules that get exchanged with protons in bulk water. In this review, we describe the basic concepts of APT imaging, particularly with regard to the benefit in clinics from the current literature. Clinical applications of APT imaging are described from two perspectives: in the diagnosis and monitoring of the treatment response in brain glioma by reflecting endogenous mobile proteins and peptides, and in the potential for stroke imaging with respect to tissue acidity.

Retrieving aerosol in a cloudy environment: aerosol product availability as a function of spatial resolution

Directory of Open Access Journals (Sweden)

L. A. Remer

2012-07-01

Full Text Available The challenge of using satellite observations to retrieve aerosol properties in a cloudy environment is to prevent contamination of the aerosol signal from clouds, while maintaining sufficient aerosol product yield to satisfy specific applications. We investigate aerosol retrieval availability at different instrument pixel resolutions using the standard MODIS aerosol cloud mask applied to MODIS data and supplemented with a new GOES-R cloud mask applied to GOES data for a domain covering North America and surrounding oceans. Aerosol product availability is not the same as the cloud free fraction and takes into account the techniques used in the MODIS algorithm to avoid clouds, reduce noise and maintain sufficient numbers of aerosol retrievals. The inherent spatial resolution of each instrument, 0.5×0.5 km for MODIS and 1×1 km for GOES, is systematically degraded to 1×1, 2×2, 1×4, 4×4 and 8×8 km resolutions and then analyzed as to how that degradation would affect the availability of an aerosol retrieval, assuming an aerosol product resolution at 8×8 km. The analysis is repeated, separately, for near-nadir pixels and those at larger view angles to investigate the effect of pixel growth at oblique angles on aerosol retrieval availability. The results show that as nominal pixel size increases, availability decreases until at 8×8 km 70% to 85% of the retrievals available at 0.5 km, nadir, have been lost. The effect at oblique angles is to further decrease availability over land but increase availability over ocean, because sun glint is found at near-nadir view angles. Finer resolution sensors (i.e., 1×1, 2×2 or even 1×4 km will retrieve aerosols in partly cloudy scenes significantly more often than sensors with nadir views of 4×4 km or coarser. Large differences in the results of the two cloud masks designed for MODIS aerosol and GOES cloud products strongly reinforce that cloud masks must be developed with specific purposes in mind and

Radiative Importance of Aerosol-Cloud Interaction

Science.gov (United States)

Tsay, Si-Chee

1999-01-01

Aerosol particles are input into the troposphere by biomass burning, among other sources. These aerosol palls cover large expanses of the earth's surface. Aerosols may directly scatter solar radiation back to space, thus increasing the earth's albedo and act to cool the earth's surface and atmosphere. Aerosols also contribute to the earth's energy balance indirectly. Hygroscopic aerosol act as cloud condensation nuclei (CCN) and thus affects cloud properties. In 1977, Twomey theorized that additional available CCN would create smaller but more numerous cloud droplets in a cloud with a given amount of liquid water. This in turn would increase the cloud albedo which would scatter additional radiation back to space and create a similar cooling pattern as the direct aerosol effect. Estimates of the magnitude of the aerosol indirect effect on a global scale range from 0.0 to -4.8 W/sq m. Thus the indirect effect can be of comparable magnitude and opposite in sign to the estimates of global greenhouse gas forcing Aerosol-cloud interaction is not a one-way process. Just as aerosols have an influence on clouds through the cloud microphysics, clouds have an influence on aerosols. Cloud droplets are solutions of liquid water and CCN, now dissolved. When the cloud droplet evaporates it leaves behind an aerosol particle. This new particle does not have to have the same properties as the original CCN. In fact, studies show that aerosol particles that result from cloud processing are larger in size than the original CCN. Optical properties of aerosol particles are dependent on the size of the particles. Larger particles have a smaller backscattering fraction, and thus less incoming solar radiation will be backscattered to space if the aerosol particles are larger. Therefore, we see that aerosols and clouds modify each other to influence the radiative balance of the earth. Understanding and quantifying the spatial and seasonal patterns of the aerosol indirect forcing may have

Unveiling aerosol-cloud interactions - Part 1: Cloud contamination in satellite products enhances the aerosol indirect forcing estimate

Science.gov (United States)

Christensen, Matthew W.; Neubauer, David; Poulsen, Caroline A.; Thomas, Gareth E.; McGarragh, Gregory R.; Povey, Adam C.; Proud, Simon R.; Grainger, Roy G.

2017-11-01

Increased concentrations of aerosol can enhance the albedo of warm low-level cloud. Accurately quantifying this relationship from space is challenging due in part to contamination of aerosol statistics near clouds. Aerosol retrievals near clouds can be influenced by stray cloud particles in areas assumed to be cloud-free, particle swelling by humidification, shadows and enhanced scattering into the aerosol field from (3-D radiative transfer) clouds. To screen for this contamination we have developed a new cloud-aerosol pairing algorithm (CAPA) to link cloud observations to the nearest aerosol retrieval within the satellite image. The distance between each aerosol retrieval and nearest cloud is also computed in CAPA. Results from two independent satellite imagers, the Advanced Along-Track Scanning Radiometer (AATSR) and Moderate Resolution Imaging Spectroradiometer (MODIS), show a marked reduction in the strength of the intrinsic aerosol indirect radiative forcing when selecting aerosol pairs that are located farther away from the clouds (-0.28±0.26 W m-2) compared to those including pairs that are within 15 km of the nearest cloud (-0.49±0.18 W m-2). The larger aerosol optical depths in closer proximity to cloud artificially enhance the relationship between aerosol-loading, cloud albedo, and cloud fraction. These results suggest that previous satellite-based radiative forcing estimates represented in key climate reports may be exaggerated due to the inclusion of retrieval artefacts in the aerosol located near clouds.

Devices and methods for generating an aerosol

KAUST Repository

Bisetti, Fabrizio

2016-03-03

Aerosol generators and methods of generating aerosols are provided. The aerosol can be generated at a stagnation interface between a hot, wet stream and a cold, dry stream. The aerosol has the benefit that the properties of the aerosol can be precisely controlled. The stagnation interface can be generated, for example, by the opposed flow of the hot stream and the cold stream. The aerosol generator and the aerosol generation methods are capable of producing aerosols with precise particle sizes and a narrow size distribution. The properties of the aerosol can be controlled by controlling one or more of the stream temperatures, the saturation level of the hot stream, and the flow times of the streams.

The GRAPE aerosol retrieval algorithm

Directory of Open Access Journals (Sweden)

G. E. Thomas

2009-11-01

Full Text Available The aerosol component of the Oxford-Rutherford Aerosol and Cloud (ORAC combined cloud and aerosol retrieval scheme is described and the theoretical performance of the algorithm is analysed. ORAC is an optimal estimation retrieval scheme for deriving cloud and aerosol properties from measurements made by imaging satellite radiometers and, when applied to cloud free radiances, provides estimates of aerosol optical depth at a wavelength of 550 nm, aerosol effective radius and surface reflectance at 550 nm. The aerosol retrieval component of ORAC has several incarnations – this paper addresses the version which operates in conjunction with the cloud retrieval component of ORAC (described by Watts et al., 1998, as applied in producing the Global Retrieval of ATSR Cloud Parameters and Evaluation (GRAPE data-set.

The algorithm is described in detail and its performance examined. This includes a discussion of errors resulting from the formulation of the forward model, sensitivity of the retrieval to the measurements and a priori constraints, and errors resulting from assumptions made about the atmospheric/surface state.

Aerosol in the containment

International Nuclear Information System (INIS)

Lanza, S.; Mariotti, P.

1986-01-01

The US program LACE (LWR Aerosol Containment Experiments), in which Italy participates together with several European countries, Canada and Japan, aims at evaluating by means of a large scale experimental activity at HEDL the retention in the pipings and primary container of the radioactive aerosol released following severe accidents in light water reactors. At the same time these experiences will make available data through which the codes used to analyse the behaviour of the aerosol in the containment and to verify whether by means of the codes of thermohydraulic computation it is possible to evaluate with sufficient accuracy variable influencing the aerosol behaviour, can be validated. This report shows and compares the results obtained by the participants in the LACE program with the aerosol containment codes NAVA 5 and CONTAIN for the pre-test computations of the test LA 1, in which an accident called containment by pass is simulated

CATS Aerosol Typing and Future Directions

Science.gov (United States)

McGill, Matt; Yorks, John; Scott, Stan; Palm, Stephen; Hlavka, Dennis; Hart, William; Nowottnick, Ed; Selmer, Patrick; Kupchock, Andrew; Midzak, Natalie;

Aerosol processing: a wind of innovation in the field of advanced heterogeneous catalysts.

Science.gov (United States)

Debecker, Damien P; Le Bras, Solène; Boissière, Cédric; Chaumonnot, Alexandra; Sanchez, Clément

2018-04-16

Aerosol processing is long known and implemented industrially to obtain various types of divided materials and nanomaterials. The atomisation of a liquid solution or suspension produces a mist of aerosol droplets which can then be transformed via a diversity of processes including spray-drying, spray pyrolysis, flame spray pyrolysis, thermal decomposition, micronisation, gas atomisation, etc. The attractive technical features of these aerosol processes make them highly interesting for the continuous, large scale, and tailored production of heterogeneous catalysts. Indeed, during aerosol processing, each liquid droplet undergoes well-controlled physical and chemical transformations, allowing for example to dry and aggregate pre-existing solid particles or to synthesise new micro- or nanoparticles from mixtures of molecular or colloidal precursors. In the last two decades, more advanced reactive aerosol processes have emerged as innovative means to synthesise tailored-made nanomaterials with tunable surface properties, textures, compositions, etc. In particular, the "aerosol-assisted sol-gel" process (AASG) has demonstrated tremendous potential for the preparation of high-performance heterogeneous catalysts. The method is mainly based on the low-cost, scalable, and environmentally benign sol-gel chemistry process, often coupled with the evaporation-induced self-assembly (EISA) concept. It allows producing micronic or submicronic, inorganic or hybrid organic-inorganic particles bearing tuneable and calibrated porous structures at different scales. In addition, pre-formed nanoparticles can be easily incorporated or formed in a "one-pot" bottom-up approach within the porous inorganic or hybrid spheres produced by such spray drying method. Thus, multifunctional catalysts with tailored catalytic activities can be prepared in a relatively simple way. This account is an overview of aerosol processed heterogeneous catalysts which demonstrated interesting performance in

Stratospheric Aerosol Measurements

Science.gov (United States)

Pueschel, Rudolf, F.; Gore, Warren J. (Technical Monitor)

1998-01-01

Stratospheric aerosols affect the atmospheric energy balance by scattering and absorbing solar and terrestrial radiation. They also can alter stratospheric chemical cycles by catalyzing heterogeneous reactions which markedly perturb odd nitrogen, chlorine and ozone levels. Aerosol measurements by satellites began in NASA in 1975 with the Stratospheric Aerosol Measurement (SAM) program, to be followed by the Stratospheric Aerosol and Gas Experiment (SAGE) starting in 1979. Both programs employ the solar occultation, or Earth limb extinction, techniques. Major results of these activities include the discovery of polar stratospheric clouds (PSCs) in both hemispheres in winter, illustrations of the impacts of major (El Chichon 1982 and Pinatubo 1991) eruptions, and detection of a negative global trend in lower stratospheric/upper tropospheric aerosol extinction. This latter result can be considered a triumph of successful worldwide sulfur emission controls. The SAGE record will be continued and improved by SAGE III, currently scheduled for multiple launches beginning in 2000 as part of the Earth Observing System (EOS). The satellite program has been supplemented by in situ measurements aboard the ER-2 (20 km ceiling) since 1974, and from the DC-8 (13 km ceiling) aircraft beginning in 1989. Collection by wire impactors and subsequent electron microscopic and X-ray energy-dispersive analyses, and optical particle spectrometry have been the principle techniques. Major findings are: (1) The stratospheric background aerosol consists of dilute sulfuric acid droplets of around 0.1 micrometer modal diameter at concentration of tens to hundreds of monograms per cubic meter; (2) Soot from aircraft amounts to a fraction of one percent of the background total aerosol; (3) Volcanic eruptions perturb the sulfuric acid, but not the soot, aerosol abundance by several orders of magnitude; (4) PSCs contain nitric acid at temperatures below 195K, supporting chemical hypotheses

The deposition - a modern phenomenon in the evaluation of inhalation risk of mining aerosols

Directory of Open Access Journals (Sweden)

Ľubomír Legáth

2007-04-01

Full Text Available The deposition is defined as an array of processes causing a part of the inhaled aerosol to remain (after its expiration in the respiratory tract. The particles retained in the respiratory tract are called deposits. The deposition encompasses of three different mechanisms: impaction, sedimentation and Brown molecular movement combined with the diffusion. The impaction remains the most potential contribution to the deposition in the conductive zone of the respiratory tract. While the sedimentation and diffusion in conjunction with the Brown molecular movement have a major impact in the respiratory area with the zero flow movement. The above listed mechanisms participate with the different ratio to the deposition at respective parts of the respiratory tract.The deposition depends on physical and chemical properties of inhaled aerosols as well as on the susceptibility of each individual. The size, shape, mass, and electric charges are among the basic characteristics of aerosols. The individual susceptibility is mainly influenced by an anatomical arrangement of respiratory tract, tidal volume, frequency of breathing, and breath holding.

Radioactive aerosols. [In Russian

Energy Technology Data Exchange (ETDEWEB)

Natanson, G L

1956-01-01

Tabulations are given presenting various published data on safe atmospheric concentrations of various radioactive and non-radioactive aerosols. Methods of determination of active aerosol concentrations and dispersion as well as the technical applications of labeled aerosols are discussed. The effect of atomic explosions are analyzed considering the nominal atomic bomb based on /sup 235/U and /sup 232/Pu equivalent to 20,000 tons of TNT.

Devices and methods for generating an aerosol

KAUST Repository

Bisetti, Fabrizio; Scribano, Gianfranco

2016-01-01

Aerosol generators and methods of generating aerosols are provided. The aerosol can be generated at a stagnation interface between a hot, wet stream and a cold, dry stream. The aerosol has the benefit that the properties of the aerosol can

Concepts of particle physics

International Nuclear Information System (INIS)

Gottfried, K.; Weisskopf, V.F.

1984-01-01

This volume elucidates basic and well-established concepts of particle physics for the autodidact who is curious about recent developments in fundamental physics. Elementary quantum mechanics is a background must. Contents, abridged: The evolution of the particle concept before the advent of quantum mechanics. Nonrelativistic quantum mechanics and atomic physics. Relativistic quantum theory. Nuclear phenomena. Subnuclear phenomena. Index

Integral fast reactor concept

International Nuclear Information System (INIS)

Chang, Y.I.; Marchaterre, J.F.; Sevy, R.H.

1984-01-01

Key features of the IFR consist of a pool-type plant arrangement, a metal fuel-based core design, and an integral fuel cycle with colocated fuel cycle facility. Both the basic concept and the technology base have been demonstrated through actual integral cycle operation in EBR-II. This paper discusses the inherent safety characteristics of the IFR concept

An aerosole generator for production of radioactive aerosoles by evaporating uranium dioxide

International Nuclear Information System (INIS)

Pusch, W.M.

1975-01-01

In the Institut for Biology of the Austrian Research Center at Seibersdorf an experiment is running to study the behaviour of radioactive aerosoles in the organism of miniature swines after inhalation. In the work under discussion the aerosole generator of the equipment used for this inhalation experiments is described by means of which the aerosole-air mixtures are produced. The main part of this generator is a gas burner for evaporating irradiated UO 2 -pellets. (orig.) [de

A study of the attachment of thoron decay products to aerosols using an aerosol centrifuge

International Nuclear Information System (INIS)

Menon, V.B.; Kotrappa, P.; Bhanti, D.P.

1980-01-01

An aerosol centrifuge is used for the study of the attachment of thoron decay products to aerosol particles under dynamic flow conditions. The number concentration of aerosols was kept high (10 5 to 10 6 particles cm -3 ) as compared to the number of decay product atoms (10 2 to 10 3 cm -3 ) as is usually the case in a mine atmosphere. The polydispersed aerosols flow in and out of a chamber containing a steady source of thoron and the aerosols tagged with the decay products were separated into different size groups by an aerosol centrifuge (Lovelace Aerosol Particle Separator). The average activity per particle was fitted as a power function of the radius in the form of Asub(p) = aRsup(b). The average value of b was found to be 1.08 +- 0.054 for particles in the radii range 0.25 to 1.35 μm and 1.34 +- 0.12 for particles in the radii range 0.1 to 0.33 μm. (author)

Finish-Kazakhstan cooperation on an aerosols sampling - testing of a new methods for nuclear monitoring improvement

International Nuclear Information System (INIS)

Tarvajnen, M.; Akhmetov, M.A.; Ptitskaya, L.D.; Osintsev, A.Yu.; Zhantikin, T.M.; Eligbaeva, G.

2001-01-01

The aerosols sampling is the powerful method of air radioactivity monitoring both the natural and artificial origin. Up to the today the IAEA does not engage of aerosols sampling study. To study of possibility of this method examination for radiation monitoring - the state authorities of Finland and the Republic of Kazakhstan - Department of Radiation and Nuclear Safety (Stuck) and Kazakhstan Atomic Energy Committee - jointly carried out the field tests in Kazakhstan. The test was began in the Kurchatov in April 2000 - at the desire of IAEA working team on Iraq - close to former Semipalatinsk test site and was ended in Astana in August of 2001. The main aim of the field test was study of possibility and appropriateness of concept and technology of aerosols sampling developed for the complete condition of environment. In the paper the role of participating sides in the field test and main results and conclusions are discussed as well. The gained experience will allow developing the method aerosols sampling for IAEA international safeguard measures strengthening application

Modification of Local Urban Aerosol Properties by Long-Range Transport of Biomass Burning Aerosol

Directory of Open Access Journals (Sweden)

Iwona S. Stachlewska

2018-03-01

Full Text Available During August 2016, a quasi-stationary high-pressure system spreading over Central and North-Eastern Europe, caused weather conditions that allowed for 24/7 observations of aerosol optical properties by using a complex multi-wavelength PollyXT lidar system with Raman, polarization and water vapour capabilities, based at the European Aerosol Research Lidar Network (EARLINET network urban site in Warsaw, Poland. During 24–30 August 2016, the lidar-derived products (boundary layer height, aerosol optical depth, Ångström exponent, lidar ratio, depolarization ratio were analysed in terms of air mass transport (HYSPLIT model, aerosol load (CAMS data and type (NAAPS model and confronted with active and passive remote sensing at the ground level (PolandAOD, AERONET, WIOS-AQ networks and aboard satellites (SEVIRI, MODIS, CATS sensors. Optical properties for less than a day-old fresh biomass burning aerosol, advected into Warsaw’s boundary layer from over Ukraine, were compared with the properties of long-range transported 3–5 day-old aged biomass burning aerosol detected in the free troposphere over Warsaw. Analyses of temporal changes of aerosol properties within the boundary layer, revealed an increase of aerosol optical depth and Ångström exponent accompanied by an increase of surface PM10 and PM2.5. Intrusions of advected biomass burning particles into the urban boundary layer seem to affect not only the optical properties observed but also the top height of the boundary layer, by moderating its increase.

Basic mathematics for the biological and social sciences

CERN Document Server

Marriott, F H C

2013-01-01

Basic Mathematics for the Biological and Social Sciences deals with the applications of basic mathematics in the biological and social sciences. Mathematical concepts that are discussed in this book include graphical methods, differentiation, trigonometrical or circular functions, limits and convergence, integration, vectors, and differential equations. The exponential function and related functions are also considered. This monograph is comprised of 11 chapters and begins with an overview of basic algebra, followed by an introduction to infinitesimal calculus, scalar and vector quantities, co

Updated aerosol module and its application to simulate secondary organic aerosols during IMPACT campaign May 2008

Directory of Open Access Journals (Sweden)

Y. P. Li

2013-07-01

Full Text Available The formation of Secondary organic aerosol (SOA was simulated with the Secondary ORGanic Aerosol Model (SORGAM by a classical gas-particle partitioning concept, using the two-product model approach, which is widely used in chemical transport models. In this study, we extensively updated SORGAM including three major modifications: firstly, we derived temperature dependence functions of the SOA yields for aromatics and biogenic VOCs (volatile organic compounds, based on recent chamber studies within a sophisticated mathematic optimization framework; secondly, we implemented the SOA formation pathways from photo oxidation (OH initiated of isoprene; thirdly, we implemented the SOA formation channel from NO3-initiated oxidation of reactive biogenic hydrocarbons (isoprene and monoterpenes. The temperature dependence functions of the SOA yields were validated against available chamber experiments, and the updated SORGAM with temperature dependence functions was evaluated with the chamber data. Good performance was found with the normalized mean error of less than 30%. Moreover, the whole updated SORGAM module was validated against ambient SOA observations represented by the summed oxygenated organic aerosol (OOA concentrations abstracted from aerosol mass spectrometer (AMS measurements at a rural site near Rotterdam, the Netherlands, performed during the IMPACT campaign in May 2008. In this case, we embedded both the original and the updated SORGAM module into the EURopean Air pollution and Dispersion-Inverse Model (EURAD-IM, which showed general good agreements with the observed meteorological parameters and several secondary products such as O3, sulfate and nitrate. With the updated SORGAM module, the EURAD-IM model also captured the observed SOA concentrations reasonably well especially those during nighttime. In contrast, the EURAD-IM model before update underestimated the observations by a factor of up to 5. The large improvements of the modeled

Aerosol characterization during project POLINAT

Energy Technology Data Exchange (ETDEWEB)

Hagen, D.E.; Hopkins, A.R.; Paladino, J.D.; Whitefield, P.D. [Missouri Univ., Rolla, MO (United States). Cloud and Aerosol Sciences Lab.; Lilenfeld, H.V. [McDonnell Douglas Aerospace-East, St. Louis, MO (United States)

1997-12-31

The objectives of the aerosol/particulate characterization measurements of project POLINAT (POLlution from aircraft emissions In the North ATlantic flight corridor) are: to search for aerosol/particulate signatures of air traffic emissions in the region of the North Atlantic Flight Corridor; to search for the aerosol/particulate component of large scale enhancement (`corridor effects`) of air traffic related species in the North Atlantic region; to determine the effective emission indices for the aerosol/particulate component of engine exhaust in both the near and far field of aircraft exhaust plumes; to measure the dispersion and transformation of the aerosol/particulate component of aircraft emissions as a function of ambient condition; to characterize background levels of aerosol/particulate concentrations in the North Atlantic Region; and to determine effective emission indices for engine exhaust particulates for regimes beyond the jet phase of plume expansion. (author) 10 refs.

Aerosol characterization during project POLINAT

Energy Technology Data Exchange (ETDEWEB)

Hagen, D E; Hopkins, A R; Paladino, J D; Whitefield, P D [Missouri Univ., Rolla, MO (United States). Cloud and Aerosol Sciences Lab.; Lilenfeld, H V [McDonnell Douglas Aerospace-East, St. Louis, MO (United States)

1998-12-31

The objectives of the aerosol/particulate characterization measurements of project POLINAT (POLlution from aircraft emissions In the North ATlantic flight corridor) are: to search for aerosol/particulate signatures of air traffic emissions in the region of the North Atlantic Flight Corridor; to search for the aerosol/particulate component of large scale enhancement (`corridor effects`) of air traffic related species in the North Atlantic region; to determine the effective emission indices for the aerosol/particulate component of engine exhaust in both the near and far field of aircraft exhaust plumes; to measure the dispersion and transformation of the aerosol/particulate component of aircraft emissions as a function of ambient condition; to characterize background levels of aerosol/particulate concentrations in the North Atlantic Region; and to determine effective emission indices for engine exhaust particulates for regimes beyond the jet phase of plume expansion. (author) 10 refs.

The effects of aerosols on climate

International Nuclear Information System (INIS)

Boucher, O.

1997-01-01

Atmospheric aerosols (fine particles suspended in the atmosphere) can play two roles in the Earth’s radiation budget. In cloud-free air, aerosols scatter sunlight, some of which is reflected back to space (direct effect). Aerosols also determine the microphysical and optical properties of clouds (indirect effect). Whereas changes in natural aerosols are probably small during the last 100 years, there has been a large increase in the concentration of anthropogenic aerosols. The magnitude of their radiative effects is still very uncertain but seems to be sufficient to mask part of the global warming expected to stem from anthropogenic greenhouse gases. This paper presents the physical mechanisms of aerosol influence on climate. We then estimate the anthropogenic aerosol radiative effects and assess the climate response to these perturbations. (author) [fr

Air classifier technology (ACT) in dry powder inhalation. Part 1 : Introduction of a novel force distribution concept (FDC) explaining the performance of a basic air classifier on adhesive mixtures

NARCIS (Netherlands)

de Boer, A H; Hagedoorn, P; Gjaltema, D; Goede, J; Frijlink, H W

2003-01-01

Air classifier technology (ACT) is introduced as part of formulation integrated dry powder inhaler development (FIDPI) to optimise the de-agglomeration of inhalation powders. Carrier retention and de-agglomeration results obtained with a basic classifier concept are discussed. The theoretical

Water content of aged aerosol

Directory of Open Access Journals (Sweden)

G. J. Engelhart

2011-02-01

Full Text Available The composition and physical properties of aged atmospheric aerosol were characterized at a remote sampling site on the northern coast of Crete, Greece during the Finokalia Aerosol Measurement Experiment in May 2008 (FAME-2008. A reduced Dry-Ambient Aerosol Size Spectrometer (DAASS was deployed to measure the aerosol water content and volumetric growth factor of fine particulate matter. The particles remained wet even at relative humidity (RH as low as 20%. The aerosol was acidic during most of the measurement campaign, which likely contributed to the water uptake at low RH. The water content observations were compared to the thermodynamic model E-AIM, neglecting any contribution of the organics to aerosol water content. There was good agreement between the water measurements and the model predictions. Adding the small amount of water associated with the organic aerosol based on monoterpene water absorption did not change the quality of the agreement. These results strongly suggest that the water uptake by aged organic aerosol is relatively small (a few percent of the total water for the conditions during FAME-08 and generally consistent with what has been observed in laboratory experiments. The water concentration measured by a Q-AMS was well correlated with the DAASS measurements and in good agreement with the predicted values for the RH of the Q-AMS inlet. This suggests that, at least for the conditions of the study, the Q-AMS can provide valuable information about the aerosol water concentrations if the sample is not dried.

AEROSOL VARIABILITY OBSERVED WITH RPAS

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B. Altstädter

2013-08-01

Full Text Available To observe the origin, vertical and horizontal distribution and variability of aerosol particles, and especially ultrafine particles recently formed, we plan to employ the remotely piloted aircraft system (RPAS Carolo-P360 "ALADINA" of TU Braunschweig. The goal of the presented project is to investigate the vertical and horizontal distribution, transport and small-scale variability of aerosol particles in the atmospheric boundary layer using RPAS. Two additional RPAS of type MASC of Tübingen University equipped with turbulence instrumentation add the opportunity to study the interaction of the aerosol concentration with turbulent transport and exchange processes of the surface and the atmosphere. The combination of different flight patterns of the three RPAS allows new insights in atmospheric boundary layer processes. Currently, the different aerosol sensors are miniaturized at the Leibniz Institute for Tropospheric Research, Leipzig and together with the TU Braunschweig adapted to fit into the RPAS. Moreover, an additional meteorological payload for measuring temperature, humidity and turbulence properties is constructed by Tübingen University. Two condensation particle counters determine the total aerosol number with a different lower detection threshold in order to investigate the horizontal and vertical aerosol variability and new particle formation (aerosol particles of some nm diameter. Further the aerosol size distribution in the range from about 0.300 to ~5 μm is given by an optical particle counter.

Aerosols from biomass combustion

Energy Technology Data Exchange (ETDEWEB)

Nussbaumer, T

2001-07-01

This report is the proceedings of a seminar on biomass combustion and aerosol production organised jointly by the International Energy Agency's (IEA) Task 32 on bio energy and the Swiss Federal Office of Energy (SFOE). This collection of 16 papers discusses the production of aerosols and fine particles by the burning of biomass and their effects. Expert knowledge on the environmental impact of aerosols, formation mechanisms, measurement technologies, methods of analysis and measures to be taken to reduce such emissions is presented. The seminar, visited by 50 participants from 11 countries, shows, according to the authors, that the reduction of aerosol emissions resulting from biomass combustion will remain a challenge for the future.

Sodium aerosol recovering device

International Nuclear Information System (INIS)

Fujimori, Koji; Ueda, Mitsuo; Tanaka, Kazuhisa.

1997-01-01

A main body of a recovering device is disposed in a sodium cooled reactor or a sodium cooled test device. Air containing sodium aerosol is sucked into the main body of the recovering device by a recycling fan and introduced to a multi-staged metal mesh filter portion. The air about against each of the metal mesh filters, and the sodium aerosol in the air is collected. The air having a reduced sodium aerosol concentration circulates passing through a recycling fan and pipelines to form a circulation air streams. Sodium aerosol deposited on each of the metal mesh filters is scraped off periodically by a scraper driving device to prevent clogging of each of the metal filters. (I.N.)

Aerosols from biomass combustion

Energy Technology Data Exchange (ETDEWEB)

Nussbaumer, T.

2001-07-01

This report is the proceedings of a seminar on biomass combustion and aerosol production organised jointly by the International Energy Agency's (IEA) Task 32 on bio energy and the Swiss Federal Office of Energy (SFOE). This collection of 16 papers discusses the production of aerosols and fine particles by the burning of biomass and their effects. Expert knowledge on the environmental impact of aerosols, formation mechanisms, measurement technologies, methods of analysis and measures to be taken to reduce such emissions is presented. The seminar, visited by 50 participants from 11 countries, shows, according to the authors, that the reduction of aerosol emissions resulting from biomass combustion will remain a challenge for the future.

Global simulations of aerosol processing in clouds

Directory of Open Access Journals (Sweden)

C. Hoose

2008-12-01

Full Text Available An explicit and detailed representation of in-droplet and in-crystal aerosol particles in stratiform clouds has been introduced in the global aerosol-climate model ECHAM5-HAM. The new scheme allows an evaluation of the cloud cycling of aerosols and an estimation of the relative contributions of nucleation and collision scavenging, as opposed to evaporation of hydrometeors in the global aerosol processing by clouds. On average an aerosol particle is cycled through stratiform clouds 0.5 times. The new scheme leads to important changes in the simulated fraction of aerosol scavenged in clouds, and consequently in the aerosol wet deposition. In general, less aerosol is scavenged into clouds with the new prognostic treatment than what is prescribed in standard ECHAM5-HAM. Aerosol concentrations, size distributions, scavenged fractions and cloud droplet concentrations are evaluated and compared to different observations. While the scavenged fraction and the aerosol number concentrations in the marine boundary layer are well represented in the new model, aerosol optical thickness, cloud droplet number concentrations in the marine boundary layer and the aerosol volume in the accumulation and coarse modes over the oceans are overestimated. Sensitivity studies suggest that a better representation of below-cloud scavenging, higher in-cloud collision coefficients, or a reduced water uptake by seasalt aerosols could reduce these biases.

REVIVING SOME BASIC CONCEPTS IN ETHICAL REGISTER

Directory of Open Access Journals (Sweden)

CARMEN COZMA

2015-11-01

Full Text Available Being sensitive to the challenges placed before us in a globalizing world, it is obviously that the ethical benchmark became one of the priorities in our individual and communitarian life. An in-depth knowledge of both the axiological and normative dimensions of ethics can open an important way for an adequate approach of today’s problems. By rethinking the foundations, we may reach accuracy as regards what does really matter in life. So, a call to revive some value-laden concepts coming from the ancient Greek moral philosophy represents the aim of this paper, to emphasize the support given us by healthy roots for reflection and understanding, in part at least, our present problematic situation in the world.

The background aerosol in the lower stratosphere and the tropospheric aerosol in the Alps. Final report; Das Hintergrundaerosol der unteren Stratosphaere und das troposphaerische Aerosol der Alpen. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Jaeger, H.; Trickl, T.

2001-06-04

As a contribution to the German Aerosol-Lidar Network lidar backscatter measurements have been carried out at Garmisch-Partenkirchen in a wide range of the atmosphere from next to the ground to altitudes beyond 30 km. The investigations, on one hand, were devoted to establishing a climatology of the aerosol extinction coefficient for the northern Alps and to prolonging the long-term measurement series of the stratospheric aerosol. On the other hand, aerosol was used as a tracer of polluted air masses in atmospheric transport studies (orographically induced vertical transport, advection of Saharan dust, as well as aerosol advection from the North american boundary layer and from large-scale wild fire in the United States and Canada). These transport processes given the seasonal cycle of the aerosol throughout the troposphere. In the free troposphere a pronounced spring-time aerosol maximum was found. The stratospheric aerosol concentration had decayed to a background-type level during the reporting period. As a consequence, the influence of smaller aerosol contributions could be distinguished such as the eruption of the volcano Shishaldin (Alaska) and aircraft emissions. (orig.) [German] Im Rahmen des deutschen Aerosollidarnetzes wurden in Garmisch-Partenkirchen Lidar-Rueckstreumessungen in einem weiten Bereich der Atmosphaere von Bodennaehe bis in ueber 30 km Hoehe durchgefuehrt. Die Arbeiten dienten zum einen der Erstellung einer Klimatologie des Aerosol-Extinktionskoeffizienten fuer die Nordalpen sowie der Verlaengerung der seit 1976 erstellten Langzeitmessreihe des stratosphaerischen Aerosols. Zum anderen fanden atmosphaerische Transportstudien statt, bei denen das Aerosol als 'Tracer' fuer Luftverschmutzung verwendet wurde (orographisch induzierter Vertikaltransport, Advektion von Saharastaub und Aerosoladvektion aus der nordamerikanischen Genzschicht und von grossflaechigen Waldbraenden in den U.S.A. und Kanada). Diese Transportprozesse bestimmen den

Statistically Optimized Inversion Algorithm for Enhanced Retrieval of Aerosol Properties from Spectral Multi-Angle Polarimetric Satellite Observations

Science.gov (United States)

Dubovik, O; Herman, M.; Holdak, A.; Lapyonok, T.; Taure, D.; Deuze, J. L.; Ducos, F.; Sinyuk, A.

2011-01-01

The proposed development is an attempt to enhance aerosol retrieval by emphasizing statistical optimization in inversion of advanced satellite observations. This optimization concept improves retrieval accuracy relying on the knowledge of measurement error distribution. Efficient application of such optimization requires pronounced data redundancy (excess of the measurements number over number of unknowns) that is not common in satellite observations. The POLDER imager on board the PARASOL microsatellite registers spectral polarimetric characteristics of the reflected atmospheric radiation at up to 16 viewing directions over each observed pixel. The completeness of such observations is notably higher than for most currently operating passive satellite aerosol sensors. This provides an opportunity for profound utilization of statistical optimization principles in satellite data inversion. The proposed retrieval scheme is designed as statistically optimized multi-variable fitting of all available angular observations obtained by the POLDER sensor in the window spectral channels where absorption by gas is minimal. The total number of such observations by PARASOL always exceeds a hundred over each pixel and the statistical optimization concept promises to be efficient even if the algorithm retrieves several tens of aerosol parameters. Based on this idea, the proposed algorithm uses a large number of unknowns and is aimed at retrieval of extended set of parameters affecting measured radiation.

Projects for the implementation of science technology society approach in basic concept of natural science course as application of optical and electrical instruments’ material

Science.gov (United States)

Satria, E.

2018-03-01

Preservice teachers in primary education should be well equipped to meet the challenges of teaching primary science effectively in 21century. The purpose of this research was to describe the projects for the implementation of Science-Technology-Society (STS) approach in Basic Concept of Natural Science course as application of optical and electrical instruments’ material by the preservice teachers in Elementary Schools Teacher Education Program. One of the reasons is the lack of preservice teachers’ ability in making projects for application of STS approach and optical and electrical instruments’ material in Basic Concept of Natural Science course. This research applied descriptive method. The instrument of the research was the researcher himself. The data were gathered through observation and documentation. Based on the results of the research, it was figured out that preservice teachers, in groups, were creatively and successful to make the projects of optical and electrical instruments assigned such as projector and doorbell. It was suggested that the construction of the instruments should be better (fixed and strong structure) and more attractive for both instruments, and used strong light source, high quality images, and it could use speaker box for projector, power battery, and heat sink for electrical instruments.

Sensitivity Studies on the Influence of Aerosols on Cloud and Precipitation Development Using WRF Mesoscale Model Simulations

Science.gov (United States)

Thompson, G.; Eidhammer, T.; Rasmussen, R.

2011-12-01

Using the WRF model in simulations of shallow and deep precipitating cloud systems, we investigated the sensitivity to aerosols initiating as cloud condensation and ice nuclei. A global climatological dataset of sulfates, sea salts, and dust was used as input for a control experiment. Sensitivity experiments with significantly more polluted conditions were conducted to analyze the resulting impacts to cloud and precipitation formation. Simulations were performed using the WRF model with explicit treatment of aerosols added to the Thompson et al (2008) bulk microphysics scheme. The modified scheme achieves droplet formation using pre-tabulated CCN activation tables provided by a parcel model. The ice nucleation is parameterized as a function of dust aerosols as well as homogeneous freezing of deliquesced aerosols. The basic processes of aerosol activation and removal by wet scavenging are considered, but aerosol characteristic size or hygroscopicity does not change due to evaporating droplets. In other words, aerosol processing was ignored. Unique aspects of this study include the usage of one to four kilometer grid spacings and the direct parameterization of ice nucleation from aerosols rather than typical temperature and/or supersaturation relationships alone. Initial results from simulations of a deep winter cloud system and its interaction with significant orography show contrasting sensitivities in regions of warm rain versus mixed liquid and ice conditions. The classical view of higher precipitation amounts in relatively clean maritime clouds with fewer but larger droplets is confirmed for regions dominated by the warm-rain process. However, due to complex interactions with the ice phase and snow riming, the simulations revealed the reverse situation in high terrain areas dominated by snow reaching the surface. Results of other cloud systems will be summarized at the conference.

Clinical Correlations as a Tool in Basic Science Medical Education

Directory of Open Access Journals (Sweden)

Brenda J. Klement

2016-01-01

Full Text Available Clinical correlations are tools to assist students in associating basic science concepts with a medical application or disease. There are many forms of clinical correlations and many ways to use them in the classroom. Five types of clinical correlations that may be embedded within basic science courses have been identified and described. (1 Correlated examples consist of superficial clinical information or stories accompanying basic science concepts to make the information more interesting and relevant. (2 Interactive learning and demonstrations provide hands-on experiences or the demonstration of a clinical topic. (3 Specialized workshops have an application-based focus, are more specialized than typical laboratory sessions, and range in complexity from basic to advanced. (4 Small-group activities require groups of students, guided by faculty, to solve simple problems that relate basic science information to clinical topics. (5 Course-centered problem solving is a more advanced correlation activity than the others and focuses on recognition and treatment of clinical problems to promote clinical reasoning skills. Diverse teaching activities are used in basic science medical education, and those that include clinical relevance promote interest, communication, and collaboration, enhance knowledge retention, and help develop clinical reasoning skills.

Retrievals and uncertainty analysis of aerosol single scattering albedo from MFRSR measurements

International Nuclear Information System (INIS)

Yin, Bangsheng; Min, Qilong; Joseph, Everette

2015-01-01

Aerosol single scattering albedo (SSA) can be retrieved from the ratio of diffuse horizontal and direct normal fluxes measured from multifilter rotating shadowband radiometer (MFRSR). In this study, the measurement channels at 415 nm and 870 nm are selected for aerosol optical depth (AOD) and Angstrom coefficient retrievals, and the measurements at 415 nm are used for aerosol SSA retrievals with the constraint of retrieved Angstrom coefficient. We extensively assessed various issues impacting on the accuracy of SSA retrieval from measurements to input parameters and assumptions. For cloud-free days with mean aerosol loading of 0.13–0.60, our sensitivity study indicated that: (1) 1% calibration uncertainty can result in 0.8–3.7% changes in retrieved SSA; (2) without considering the cosine respond correction and/or forward scattering correction will result in underestimation of 1.1–3.3% and/or 0.73% in retrieved SSA; (3) an overestimation of 0.1 in asymmetry factor can result in an underestimation of 2.54–3.4% in retrieved SSA; (4) for small aerosol loading (e.g., 0.13), the uncertainty associated with the choice of Rayleigh optical depth value can result in non-negligible change in retrieved SSA (e.g., 0.015); (5) an uncertainty of 0.05 for surface albedo can result in changes of 1.49–5.4% in retrieved SSA. We applied the retrieval algorithm to the MFRSR measurements at the Atmospheric Radiation Measurements (ARM) Southern Great Plains (SGP) site. The retrieved results of AOD, Angstrom coefficient, and SSA are basically consistent with other independent measurements from co-located instruments at the site. - Highlights: • Aerosol SSA is derived from MFRSR measured diffuse to direct normal irradiance ratio. • We extensively assessed various issues impacting on the accuracy of SSA retrieval. • The issues are mainly from measurements and model input parameters and assumptions. • We applied the retrieval algorithm to the MFRSR measurements at ARM SGP

The physico-chemical evolution of atmospheric aerosols and the gas-particle partitioning of inorganic aerosol during KORUS-AQ

Science.gov (United States)

Lee, T.; Park, T.; Lee, J. B.; Lim, Y. J.; Ahn, J.; Park, J. S.; Soo, C. J.; Desyaterik, Y.; Collett, J. L., Jr.

2017-12-01

Aerosols influence climate change directly by scattering and absorption and indirectly by acting as cloud condensation nuclei and some of the effects of aerosols are reduction in visibility, deterioration of human health, and deposition of pollutants to ecosystems. Urban area is large source of aerosols and aerosol precursors. Aerosol sources are both local and from long-range transport. Long-range transport processed aerosol are often dominant sources of aerosol pollution in Korea. To improve our knowledge of aerosol chemistry, Korea and U.S-Air Quality (KORUS-AQ) of Aircraft-based aerosol measurement took place in and around Seoul, Korea during May and June 2016. KORUS-AQ campaigns were conducted to study the chemical characterization and processes of pollutants in the Seoul Metropolitan area to regional scales of Korean peninsula. Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed on aircraft platforms on-board DC-8 (NASA) aircraft. We characterized aerosol chemical properties and mass concentrations of sulfate, nitrate, ammonium and organics in polluted air plumes and investigate the spatial and vertical distribution of the species. The results of studies show that organics is predominant in Aerosol and a significant fraction of the organics is oxygenated organic aerosol (OOA) at the high altitude. Both Nitrate and sulfate can partition between the gas and particle phases. The ratios for HNO3/(N(V) (=gaseous HNO3 + particulate Nitrate) and SO2/(SO2+Sulfate) were found to exhibit quite different distributions between the particles and gas phase for the locations during KORUS-AQ campaign, representing potential for formation of additional particulate nitrate and sulfate. The results of those studies can provide highly resolved temporal and spatial air pollutant, which are valuable for air quality model input parameters for aerosol behaviour.

The treatment of bronchial obstruction by beta/sub 2/-agonist and anti-cholinergic aerosol. Advantages of associating the two types of substance

Energy Technology Data Exchange (ETDEWEB)

Minette, A.; Marcq, M.

1980-01-01

The authors review the basic aspects of bronchodilatory treatment using beta/sub 2/-agonist and atropinic aerosols; present the results of a review of literature on the subject of the toxicity of various vector gases used in aerosols of this type; discuss the problems associated with the deposition disparity of aerosols in normal and pathological lungs; present and discuss the results of the prevalence of positive responses to atropine methyl-nitrate and to beta-agonist given in aerosol form to a group of subjects with reversible bronchial obstruction; discuss the advantages of oxitropium bromide, an atropic substance which has recently been discovered and which is apparently more interesting than ipratropium bromide, against the background of the ventilatory effects as observed for these 2 substances on 19 patients suffering from reversible bronchial obstruction; and discuss the advantages of associating atropinic and beta/sub 2/-agonist substances in the same aerosol on the bass of the effects of a recently-developed preparation which combines fenoterol and ipratropium bromide. 57 refs.

MATRIX (Multiconfiguration Aerosol TRacker of mIXing state: an aerosol microphysical module for global atmospheric models

Directory of Open Access Journals (Sweden)

S. E. Bauer

2008-10-01

Full Text Available A new aerosol microphysical module MATRIX, the Multiconfiguration Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS climate model (ModelE are described. This module, which is based on the quadrature method of moments (QMOM, represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol population, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble aerosol populations.

A detailed model description and results of box-model simulations of various aerosol population configurations are presented. The box model experiments demonstrate the dependence of cloud activating aerosol number concentration on the aerosol population configuration; comparisons to sectional models are quite favorable. MATRIX is incorporated into the GISS climate model and simulations are carried out primarily to assess its performance/efficiency for global-scale atmospheric model application. Simulation results were compared with aircraft and station measurements of aerosol mass and number concentration and particle size to assess the ability of the new method to yield data suitable for such comparison. The model accurately captures the observed size distributions in the Aitken and accumulation modes up to particle diameter 1 μm, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment

Cloud-Resolving Model Simulations of Aerosol-Cloud Interactions Triggered by Strong Aerosol Emissions in the Arctic

Science.gov (United States)

Wang, H.; Kravitz, B.; Rasch, P. J.; Morrison, H.; Solomon, A.

2014-12-01

Previous process-oriented modeling studies have highlighted the dependence of effectiveness of cloud brightening by aerosols on cloud regimes in warm marine boundary layer. Cloud microphysical processes in clouds that contain ice, and hence the mechanisms that drive aerosol-cloud interactions, are more complicated than in warm clouds. Interactions between ice particles and liquid drops add additional levels of complexity to aerosol effects. A cloud-resolving model is used to study aerosol-cloud interactions in the Arctic triggered by strong aerosol emissions, through either geoengineering injection or concentrated sources such as shipping and fires. An updated cloud microphysical scheme with prognostic aerosol and cloud particle numbers is employed. Model simulations are performed in pure super-cooled liquid and mixed-phase clouds, separately, with or without an injection of aerosols into either a clean or a more polluted Arctic boundary layer. Vertical mixing and cloud scavenging of particles injected from the surface is still quite efficient in the less turbulent cold environment. Overall, the injection of aerosols into the Arctic boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. The pure liquid clouds are more susceptible to the increase in aerosol number concentration than the mixed-phase clouds. Rain production processes are more effectively suppressed by aerosol injection, whereas ice precipitation (snow) is affected less; thus the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. Aerosol injection into a clean boundary layer results in a greater cloud albedo increase than injection into a polluted one, consistent with current knowledge about aerosol-cloud interactions. Unlike previous studies investigating warm clouds, the impact of dynamical feedback due to precipitation changes is small. According to these results, which are dependent upon the representation of ice nucleation

Triatominae biochemistry goes to school: evaluation of a novel tool for teaching basic biochemical concepts of Chagas disease vectors.

Science.gov (United States)

Cunha, Leonardo Rodrigues; Cudischevitch, Cecília de Oliveira; Carneiro, Alan Brito; Macedo, Gustavo Bartholomeu; Lannes, Denise; Silva-Neto, Mário Alberto Cardoso da

2014-01-01

We evaluate a new approach to teaching the basic biochemistry mechanisms that regulate the biology of Triatominae, major vectors of Trypanosoma cruzi, the causative agent of Chagas disease. We have designed and used a comic book, "Carlos Chagas: 100 years after a hero's discovery" containing scientific information obtained by seven distinguished contemporary Brazilian researchers working with Triatominaes. Students (22) in the seventh grade of a public elementary school received the comic book. The study was then followed up by the use of Concept Maps elaborated by the students. Six Concept Maps elaborated by the students before the introduction of the comic book received an average score of 7. Scores rose to an average of 45 after the introduction of the comic book. This result suggests that a more attractive content can greatly improve the knowledge and conceptual understanding among students not previously exposed to insect biochemistry. In conclusion, this study illustrates an alternative to current strategies of teaching about the transmission of neglected diseases. It also promotes the diffusion of the scientific knowledge produced by Brazilian researchers that may stimulate students to choose a scientific career. © 2014 The International Union of Biochemistry and Molecular Biology.

Contents and assessment of basic tourism resources

OpenAIRE

Knezevic, Rade

2008-01-01

The article looks at the attractive factors of basic tourism resources and the structure of their attractions. The general term ‘resource’ refers to both natural and anthropogenic resources, while the content of this concept refers to elements used in creating a tourism product. Basic tourism resources are the most important factors of tourism processes, with a vital attribute of direct and indirect tourism resources being their substitutability. Natural (biotropic) resources are consid...

Development and first application of an Aerosol Collection Module (ACM) for quasi online compound specific aerosol measurements

Science.gov (United States)

Hohaus, Thorsten; Kiendler-Scharr, Astrid; Trimborn, Dagmar; Jayne, John; Wahner, Andreas; Worsnop, Doug

2010-05-01

Atmospheric aerosols influence climate and human health on regional and global scales (IPCC, 2007). In many environments organics are a major fraction of the aerosol influencing its properties. Due to the huge variety of organic compounds present in atmospheric aerosol current measurement techniques are far from providing a full speciation of organic aerosol (Hallquist et al., 2009). The development of new techniques for compound specific measurements with high time resolution is a timely issue in organic aerosol research. Here we present first laboratory characterisations of an aerosol collection module (ACM) which was developed to allow for the sampling and transfer of atmospheric PM1 aerosol. The system consists of an aerodynamic lens system focussing particles on a beam. This beam is directed to a 3.4 mm in diameter surface which is cooled to -30 °C with liquid nitrogen. After collection the aerosol sample can be evaporated from the surface by heating it to up to 270 °C. The sample is transferred through a 60cm long line with a carrier gas. In order to test the ACM for linearity and sensitivity we combined it with a GC-MS system. The tests were performed with octadecane aerosol. The octadecane mass as measured with the ACM-GC-MS was compared versus the mass as calculated from SMPS derived total volume. The data correlate well (R2 0.99, slope of linear fit 1.1) indicating 100 % collection efficiency. From 150 °C to 270 °C no effect of desorption temperature on transfer efficiency could be observed. The ACM-GC-MS system was proven to be linear over the mass range 2-100 ng and has a detection limit of ~ 2 ng. First experiments applying the ACM-GC-MS system were conducted at the Jülich Aerosol Chamber. Secondary organic aerosol (SOA) was formed from ozonolysis of 600 ppbv of b-pinene. The major oxidation product nopinone was detected in the aerosol and could be shown to decrease from 2 % of the total aerosol to 0.5 % of the aerosol over the 48 hours of

Establishing the Basic Concepts of a Healthy Physical Education through an Expert Method

Directory of Open Access Journals (Sweden)

Carlos Javier López Gutiérrez

2011-11-01

Full Text Available This paper investigates the basic knowledge needed by the sports practitioner who wishes to have a healthy physical education. To determine the necessary basic knowledge, we used a methodology of standard expertise, delving further into the subject by means of a semistructured interview. The interview was taped, transcribed and analyzed through the program Nudist NVivo. We have grouped the common responses emerging from the analysis into different categories, thus obtaining a total of 9 basic considerations which should be habitually transmitted to Physical Education students, so that they may achieve adequate self-management in the practice of physical activity.

Play Therapy: Basics and Beyond.

Science.gov (United States)

Kottman, Terry

This book provides an atheoretical orientation to basic concepts involved in play therapy and an introduction to different skills used in play therapy. The demand for mental professionals and school counselors who have training and expertise in using play as a therapeutic tool when working with children has increased tremendously. In response to…

Meteorological support for aerosol radiometers: special aerosol sources

Energy Technology Data Exchange (ETDEWEB)

Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

1988-07-01

A new method is described for transfer of the measure of unit volume activity of radioactive aerosols from the state special standard to the working instruments in the stage of regular operation. The differences from existing methods are examined. The principal distinction of the new method is the possibility of direct (rather than through the conversion factor) determination and subsequent testing of the fundamental meteorological characteristics of the instrument by means of special aerosol sources, which fosters a significant reduction in individual components of the indicated errors.

Potential climatic effects of anthropogenic aerosols

International Nuclear Information System (INIS)

Pueschel, R.F.

1993-01-01

Aerosols act as part of the climate system through their influence on solar and terrestrial radiation. The effect of anthropogenic aerosols on the reduction of visibility is explored in this chapter. Elemental carbon has been identified as the most effective visibility-reducing species. Most of the visibility reduction is due to particles with diameter smaller than 2.5 μm. Studies indicate that sulfate is also a very important aerosol species that results in low visibility and high turbidity. Radiative properties such as aerosol single-scattering albedo values and absorption-to-backscatter ratios purported to produce warming or cooling effects of aerosols are discussed. It is concluded that aerosol clouds have a tendency to cool when they are over a low-albedo surface and have a tendency to warm when they are over high-albedo surfaces such as snow. Anthropogenic aerosols have a tendency to warm the earth's atmospheric system, based on calculations and assumed aerosol optical properties. However, this effect is somewhat offset by the absorption and re-emission into space of infrared terrestrial radiation. The net effect depends on the ratio of the absorption coefficients in the visible and infrared and also on the surface albedo. The effects on infrared radiation are documented for two anthropogenic aerosol sources in the United States, the Denver metropolitan area and power plant plumes in New Mexico, through calculations and measurements. Measured cooling rates within an aerosol plume are not sufficient to offset the warming rate due to absorption of short-wave radiation. Research indicates that anthropogenic aerosols can possibly cause local-scale warming of the atmosphere, but global-scale climatic effects remain an open question

Basics of Computer Networking

CERN Document Server

Robertazzi, Thomas

2012-01-01

Springer Brief Basics of Computer Networking provides a non-mathematical introduction to the world of networks. This book covers both technology for wired and wireless networks. Coverage includes transmission media, local area networks, wide area networks, and network security. Written in a very accessible style for the interested layman by the author of a widely used textbook with many years of experience explaining concepts to the beginner.

Spatiotemporal variability and contribution of different aerosol types to the aerosol optical depth over the Eastern Mediterranean

Directory of Open Access Journals (Sweden)

A. K. Georgoulias

2016-11-01

Full Text Available This study characterizes the spatiotemporal variability and relative contribution of different types of aerosols to the aerosol optical depth (AOD over the Eastern Mediterranean as derived from MODIS (Moderate Resolution Imaging Spectroradiometer Terra (March 2000–December 2012 and Aqua (July 2002–December 2012 satellite instruments. For this purpose, a 0.1° × 0.1° gridded MODIS dataset was compiled and validated against sun photometric observations from the AErosol RObotic NETwork (AERONET. The high spatial resolution and long temporal coverage of the dataset allows for the determination of local hot spots like megacities, medium-sized cities, industrial zones and power plant complexes, seasonal variabilities and decadal averages. The average AOD at 550 nm (AOD550 for the entire region is ∼ 0.22 ± 0.19, with maximum values in summer and seasonal variabilities that can be attributed to precipitation, photochemical production of secondary organic aerosols, transport of pollution and smoke from biomass burning in central and eastern Europe and transport of dust from the Sahara and the Middle East. The MODIS data were analyzed together with data from other satellite sensors, reanalysis projects and a chemistry–aerosol-transport model using an optimized algorithm tailored for the region and capable of estimating the contribution of different aerosol types to the total AOD550. The spatial and temporal variability of anthropogenic, dust and fine-mode natural aerosols over land and anthropogenic, dust and marine aerosols over the sea is examined. The relative contribution of the different aerosol types to the total AOD550 exhibits a low/high seasonal variability over land/sea areas, respectively. Overall, anthropogenic aerosols, dust and fine-mode natural aerosols account for ∼ 51, ∼ 34 and ∼ 15 % of the total AOD550 over land, while, anthropogenic aerosols, dust and marine aerosols account ∼ 40, ∼ 34

Aerosol characterization over the southeastern United States using high resolution aerosol mass spectrometry: spatial and seasonal variation of aerosol composition, sources, and organic nitrates

Science.gov (United States)

Xu, L.; Suresh, S.; Guo, H.; Weber, R. J.; Ng, N. L.

2015-04-01

contributes 63-100% of total measured nitrates in summer. Further, the contribution of organic nitrates to total OA is estimated to be 5-12% in summer, suggesting that organic nitrates are important components in the ambient aerosol in the southeastern US. The spatial distribution of OA is investigated by comparing simultaneous HR-ToF-AMS measurements with ACSM measurements at two different sampling sites. OA is found to be spatially homogeneous in summer, possibly due to stagnant air mass and a dominant amount of regional SOA in the southeastern US. The homogeneity is less in winter, which is likely due to spatial variation of primary emissions. We observed that the seasonality of OA concentration shows a clear urban/rural contrast. While OA exhibits weak seasonal variation in the urban sites, its concentration is higher in summer than winter for rural sites. This observation from our year-long measurements is consistent with 14 years of organic carbon (OC) data from the SouthEastern Aerosol Research and Characterization (SEARCH) network. The comparison between short-term measurements with advanced instruments and long-term measurements of basic air quality indicators not only tests the robustness of the short-term measurements but also provides insights in interpreting long-term measurements. We find that OA factors resolved from PMF analysis on HR-ToF-AMS measurements have distinctly different diurnal variations. The compensation of OA factors with different diurnal trends is one possible reason for the repeatedly observed, relatively flat OA diurnal profile in the southeastern US. In addition, analysis of long-term measurements shows that the correlation between OC and sulfate is substantially higher in summer than winter. This seasonality could be partly due to the effects of sulfate on isoprene SOA formation as revealed by the short-term, intensive measurements.

MATRIX-VBS (v1.0): Implementing an Evolving Organic Aerosol Volatility in an Aerosol Microphysics Model

Science.gov (United States)

Gao, Chloe Y.; Tsigaridis, Kostas; Bauer, Susanne E.

2017-01-01

The gas-particle partitioning and chemical aging of semi-volatile organic aerosol are presented in a newly developed box model scheme, where its effect on the growth, composition, and mixing state of particles is examined. The volatility-basis set (VBS) framework is implemented into the aerosol microphysical scheme MATRIX (Multiconfiguration Aerosol TRacker of mIXing state), which resolves mass and number aerosol concentrations and in multiple mixing-state classes. The new scheme, MATRIX-VBS, has the potential to significantly advance the representation of organic aerosols in Earth system models by improving upon the conventional representation as non-volatile particulate organic matter, often also with an assumed fixed size distribution. We present results from idealized cases representing Beijing, Mexico City, a Finnish forest, and a southeastern US forest, and investigate the evolution of mass concentrations and volatility distributions for organic species across the gas and particle phases, as well as assessing their mixing state among aerosol populations. Emitted semi-volatile primary organic aerosols evaporate almost completely in the intermediate-volatility range, while they remain in the particle phase in the low-volatility range. Their volatility distribution at any point in time depends on the applied emission factors, oxidation by OH radicals, and temperature. We also compare against parallel simulations with the original scheme, which represented only the particulate and non-volatile component of the organic aerosol, examining how differently the condensed-phase organic matter is distributed across the mixing states in the model. The results demonstrate the importance of representing organic aerosol as a semi-volatile aerosol, and explicitly calculating the partitioning of organic species between the gas and particulate phases.

Raman microscopy of size-segregated aerosol particles, collected at the Sonnblick Observatory in Austria

Science.gov (United States)

Ofner, Johannes; Kasper-Giebl, Anneliese; Kistler, Magdalena; Matzl, Julia; Schauer, Gerhard; Hitzenberger, Regina; Lohninger, Johann; Lendl, Bernhard

2014-05-01

Size classified aerosol samples were collected using low pressure impactors in July 2013 at the high alpine background site Sonnnblick. The Sonnblick Observatory is located in the Austrian Alps, at the summit of Sonnblick 3100 m asl. Sampling was performed in parallel on the platform of the Observatory and after the aerosol inlet. The inlet is constructed as a whole air inlet and is operated at an overall sampling flow of 137 lpm and heated to 30 °C. Size cuts of the eight stage low pressure impactors were from 0.1 to 12.8 µm a.d.. Alumina foils were used as sample substrates for the impactor stages. In addition to the size classified aerosol sampling overall aerosol mass (Sharp Monitor 5030, Thermo Scientific) and number concentrations (TSI, CPC 3022a; TCC-3, Klotz) were determined. A Horiba LabRam 800HR Raman microscope was used for vibrational mapping of an area of about 100 µm x 100 µm of the alumina foils at a resolution of about 0.5 µm. The Raman microscope is equipped with a laser with an excitation wavelength of 532 nm and a grating with 300 gr/mm. Both optical images and the related chemical images were combined and a chemometric investigation of the combined images was done using the software package Imagelab (Epina Software Labs). Based on the well-known environment, a basic assignment of Raman signals of single particles is possible at a sufficient certainty. Main aerosol constituents e.g. like sulfates, black carbon and mineral particles could be identified. First results of the chemical imaging of size-segregated aerosol, collected at the Sonnblick Observatory, will be discussed with respect to standardized long-term measurements at the sampling station. Further, advantages and disadvantages of chemical imaging with subsequent chemometric investigation of the single images will be discussed and compared to the established methods of aerosol analysis. The chemometric analysis of the dataset is focused on mixing and variation of single compounds at

Aerosol generation and delivery in medical applications

International Nuclear Information System (INIS)

Soni, P.S.; Raghunath, B.

1998-01-01

It is well established that radioaerosol lung technique by inhalation is a very versatile technique in the evaluation of health effects and medical diagnostic applications, especially to detect chronic obstructive pulmonary diseases, their defence mechanism permeability and many others. Most important part of aerosol technology is to generate reproducibly stable diagnostic radioaerosols of known characteristics. Many compressed air atomisers are commercially available for generating aerosols but they have limited utility in aerosol inhalation, either because of large droplet size, low aerosol output or high airflow rates. There is clearly a need for a versatile and economical aerosol generation/inhalation system that can produce dry labelled aerosol particles with high deep lung delivery efficiency suitable for clinical studies. BARC (Bhabha Atomic Research Centre) has developed a dry aerosol generation/delivery system which operates on compressed air and generates dry polydisperse aerosols. This system is described along with an assessment of the aerosol characteristics and efficiency for diagnosis of various respiratory disorders

A Concept Transformation Learning Model for Architectural Design Learning Process

Science.gov (United States)

Wu, Yun-Wu; Weng, Kuo-Hua; Young, Li-Ming

2016-01-01

Generally, in the foundation course of architectural design, much emphasis is placed on teaching of the basic design skills without focusing on teaching students to apply the basic design concepts in their architectural designs or promoting students' own creativity. Therefore, this study aims to propose a concept transformation learning model to…

Mathematical Modeling in Mathematics Education: Basic Concepts and Approaches

Science.gov (United States)

Erbas, Ayhan Kürsat; Kertil, Mahmut; Çetinkaya, Bülent; Çakiroglu, Erdinç; Alacaci, Cengiz; Bas, Sinem

2014-01-01

Mathematical modeling and its role in mathematics education have been receiving increasing attention in Turkey, as in many other countries. The growing body of literature on this topic reveals a variety of approaches to mathematical modeling and related concepts, along with differing perspectives on the use of mathematical modeling in teaching and…

Aerosol Retrievals from Proposed Satellite Bistatic Lidar Observations: Algorithm and Information Content

Science.gov (United States)

Alexandrov, M. D.; Mishchenko, M. I.

2017-12-01

Accurate aerosol retrievals from space remain quite challenging and typically involve solving a severely ill-posed inverse scattering problem. We suggested to address this ill-posedness by flying a bistatic lidar system. Such a system would consist of formation flying constellation of a primary satellite equipped with a conventional monostatic (backscattering) lidar and an additional platform hosting a receiver of the scattered laser light. If successfully implemented, this concept would combine the measurement capabilities of a passive multi-angle multi-spectral polarimeter with the vertical profiling capability of a lidar. Thus, bistatic lidar observations will be free of deficiencies affecting both monostatic lidar measurements (caused by the highly limited information content) and passive photopolarimetric measurements (caused by vertical integration and surface reflection).We present a preliminary aerosol retrieval algorithm for a bistatic lidar system consisting of a high spectral resolution lidar (HSRL) and an additional receiver flown in formation with it at a scattering angle of 165 degrees. This algorithm was applied to synthetic data generated using Mie-theory computations. The model/retrieval parameters in our tests were the effective radius and variance of the aerosol size distribution, complex refractive index of the particles, and their number concentration. Both mono- and bimodal aerosol mixtures were considered. Our algorithm allowed for definitive evaluation of error propagation from measurements to retrievals using a Monte Carlo technique, which involves random distortion of the observations and statistical characterization of the resulting retrieval errors. Our tests demonstrated that supplementing a conventional monostatic HSRL with an additional receiver dramatically increases the information content of the measurements and allows for a sufficiently accurate characterization of tropospheric aerosols.

What is the impact of natural variability and aerosol-cloud interaction on the effective radiative forcing of anthropogenic aerosol?

Science.gov (United States)

Fiedler, S.; Stevens, B.; Mauritsen, T.

2017-12-01

State-of-the-art climate models have persistently shown a spread in estimates of the effective radiative forcing (ERF) associated with anthropogenic aerosol. Different reasons for the spread are known, but their relative importance is poorly understood. In this presentation we investigate the role of natural atmospheric variability, global patterns of aerosol radiative effects, and magnitudes of aerosol-cloud interaction in controlling the ERF of anthropogenic aerosol (Fiedler et al., 2017). We use the Earth system model MPI-ESM1.2 for conducting ensembles of atmosphere-only simulations and calculate the shortwave ERF of anthropogenic aerosol at the top of the atmosphere. The radiative effects are induced with the new parameterisation MACv2-SP (Stevens et al., 2017) that prescribes observationally constrained anthropogenic aerosol optical properties and an associated Twomey effect. Firstly, we compare the ERF of global patterns of anthropogenic aerosol from the mid-1970s and today. Our results suggest that such a substantial pattern difference has a negligible impact on the global mean ERF, when the natural variability of the atmosphere is considered. The clouds herein efficiently mask the clear-sky contributions to the forcing and reduce the detectability of significant anthropogenic aerosol radiative effects in all-sky conditions. Secondly, we strengthen the forcing magnitude through increasing the effect of aerosol-cloud interaction by prescribing an enhanced Twomey effect. In that case, the different spatial pattern of aerosol radiative effects from the mid-1970s and today causes a moderate change (15%) in the ERF of anthropogenic aerosol in our model. This finding lets us speculate that models with strong aerosol-cloud interactions would show a stronger ERF change with anthropogenic aerosol patterns. Testing whether the anthropogenic aerosol radiative forcing is model-dependent under prescribed aerosol conditions is currently ongoing work using MACv2-SP in

Satellite Remote Sensing: Aerosol Measurements

Science.gov (United States)

Kahn, Ralph A.

2013-01-01

Aerosols are solid or liquid particles suspended in the air, and those observed by satellite remote sensing are typically between about 0.05 and 10 microns in size. (Note that in traditional aerosol science, the term "aerosol" refers to both the particles and the medium in which they reside, whereas for remote sensing, the term commonly refers to the particles only. In this article, we adopt the remote-sensing definition.) They originate from a great diversity of sources, such as wildfires, volcanoes, soils and desert sands, breaking waves, natural biological activity, agricultural burning, cement production, and fossil fuel combustion. They typically remain in the atmosphere from several days to a week or more, and some travel great distances before returning to Earth's surface via gravitational settling or washout by precipitation. Many aerosol sources exhibit strong seasonal variability, and most experience inter-annual fluctuations. As such, the frequent, global coverage that space-based aerosol remote-sensing instruments can provide is making increasingly important contributions to regional and larger-scale aerosol studies.

MODIS Observation of Aerosols over Southern Africa During SAFARI 2000: Data, Validation, and Estimation of Aerosol Radiative Forcing

Science.gov (United States)

Ichoku, Charles; Kaufman, Yoram; Remer, Lorraine; Chu, D. Allen; Mattoo, Shana; Tanre, Didier; Levy, Robert; Li, Rong-Rong; Kleidman, Richard; Lau, William K. M. (Technical Monitor)

2001-01-01

Aerosol properties, including optical thickness and size parameters, are retrieved operationally from the MODIS sensor onboard the Terra satellite launched on 18 December 1999. The predominant aerosol type over the Southern African region is smoke, which is generated from biomass burning on land and transported over the southern Atlantic Ocean. The SAFARI-2000 period experienced smoke aerosol emissions from the regular biomass burning activities as well as from the prescribed burns administered on the auspices of the experiment. The MODIS Aerosol Science Team (MAST) formulates and implements strategies for the retrieval of aerosol products from MODIS, as well as for validating and analyzing them in order to estimate aerosol effects in the radiative forcing of climate as accurately as possible. These activities are carried out not only from a global perspective, but also with a focus on specific regions identified as having interesting characteristics, such as the biomass burning phenomenon in southern Africa and the associated smoke aerosol, particulate, and trace gas emissions. Indeed, the SAFARI-2000 aerosol measurements from the ground and from aircraft, along with MODIS, provide excellent data sources for a more intensive validation and a closer study of the aerosol characteristics over Southern Africa. The SAFARI-2000 ground-based measurements of aerosol optical thickness (AOT) from both the automatic Aerosol Robotic Network (AERONET) and handheld Sun photometers have been used to validate MODIS retrievals, based on a sophisticated spatio-temporal technique. The average global monthly distribution of aerosol from MODIS has been combined with other data to calculate the southern African aerosol daily averaged (24 hr) radiative forcing over the ocean for September 2000. It is estimated that on the average, for cloud free conditions over an area of 9 million square kin, this predominantly smoke aerosol exerts a forcing of -30 W/square m C lose to the terrestrial

Basic concepts of philosophy of management and corporations

DEFF Research Database (Denmark)

Rendtorff, Jacob Dahl

2013-01-01

This chapter presents some fundamental concepts of the philosophy of management and corporations by addressing the problem of corporate legitimacy and Immanuel Kant’s distinction between theoretical, practical, and aesthetic reason and judgment. This chapter begins with a general definition...... of philosophy of management and corporations and continues by presenting its ontological and epistemological underpinnings. This approach is used to address the relation between economics, business ethics, and philosophy of management. Finally, ethical and aesthetic judgment is presented as the mediator between...... theoretical, aesthetic, and practical reason in philosophy of management....

Modelling and numerical simulation of the General Dynamic Equation of aerosols; Modelisation et simulation des aerosols atmospheriques

Energy Technology Data Exchange (ETDEWEB)

Debry, E.

2005-01-15

Chemical-transport models are now able to describe in a realistic way gaseous pollutants behavior in the atmosphere. Nevertheless atmospheric pollution also exists as fine suspended particles, called aerosols, which interact with gaseous phase, solar radiation, and have their own dynamic behavior. The goal of this thesis is the modelling and numerical simulation of the General Dynamic Equation of aerosols (GDE). Part I deals with some theoretical aspects of aerosol modelling. Part II is dedicated to the building of one size resolved aerosol model (SIREAM). In part III we perform the reduction of this model in order to use it in dispersion models as POLAIR3D. Several modelling issues are still opened: organic aerosol matter, externally mixed aerosols, coupling with turbulent mixing, and nano-particles. (author)

The European aerosol budget in 2006

Directory of Open Access Journals (Sweden)

J. M. J. Aan de Brugh

2011-02-01

Full Text Available This paper presents the aerosol budget over Europe in 2006 calculated with the global transport model TM5 coupled to the size-resolved aerosol module M7. Comparison with ground observations indicates that the model reproduces the observed concentrations quite well with an expected slight underestimation of PM₁₀ due to missing emissions (e.g. resuspension. We model that a little less than half of the anthropogenic aerosols emitted in Europe are exported and the rest is removed by deposition. The anthropogenic aerosols are removed mostly by rain (95% and only 5% is removed by dry deposition. For the larger natural aerosols, especially sea salt, a larger fraction is removed by dry processes (sea salt: 70%, mineral dust: 35%. We model transport of aerosols in the jet stream in the higher atmosphere and an import of Sahara dust from the south at high altitudes. Comparison with optical measurements shows that the model reproduces the Ångström parameter very well, which indicates a correct simulation of the aerosol size distribution. However, we underestimate the aerosol optical depth. Because the surface concentrations are close to the observations, the shortage of aerosol in the model is probably at higher altitudes. We show that the discrepancies are mainly caused by an overestimation of wet-removal rates. To match the observations, the wet-removal rates have to be scaled down by a factor of about 5. In that case the modelled ground-level concentrations of sulphate and sea salt increase by 50% (which deteriorates the match, while other components stay roughly the same. Finally, it is shown that in particular events, improved fire emission estimates may significantly improve the ability of the model to simulate the aerosol optical depth. We stress that discrepancies in aerosol models can be adequately analysed if all models would provide (regional aerosol budgets, as presented in the current study.

Aerosol metrology: aerodynamic and electrostatic techniques

International Nuclear Information System (INIS)

Prodi, V.

1988-01-01

Aerosols play an ever increasing role in science, engineering and especially in industrial and environmental hygiene. They are being studied since a long time, but only recently the progress in aerosol instrumentation has made it possible to pose of aerosol metrology, especially the problem of absolute measurements, as based directly on measurements of fundamental quantities. On the basis of absolute measurements, the hierarchy of standards can be prepared and adequately disseminated. In the aerosol field, the quantities to be measured are mainly size, charge, density, and shape. In this paper a possible standardisation framework for aerosols is proposed, for the main physical quantities

Landscape fires dominate terrestrial natural aerosol - climate feedbacks

Science.gov (United States)

Scott, C.; Arnold, S.; Monks, S. A.; Asmi, A.; Paasonen, P.; Spracklen, D. V.

2017-12-01

The terrestrial biosphere is an important source of natural aerosol including landscape fire emissions and secondary organic aerosol (SOA) formed from biogenic volatile organic compounds (BVOCs). Atmospheric aerosol alters the Earth's climate by absorbing and scattering radiation (direct radiative effect; DRE) and by perturbing the properties of clouds (aerosol indirect effect; AIE). Natural aerosol sources are strongly controlled by, and can influence, climate; giving rise to potential natural aerosol-climate feedbacks. Earth System Models (ESMs) include a description of some of these natural aerosol-climate feedbacks, predicting substantial changes in natural aerosol over the coming century with associated radiative perturbations. Despite this, the sensitivity of natural aerosols simulated by ESMs to changes in climate or emissions has not been robustly tested against observations. Here we combine long-term observations of aerosol number and a global aerosol microphysics model to assess terrestrial natural aerosol-climate feedbacks. We find a strong positive relationship between the summertime anomaly in observed concentration of particles greater than 100 nm diameter and the anomaly in local air temperature. This relationship is reproduced by the model and driven by variability in dynamics and meteorology, as well as natural sources of aerosol. We use an offline radiative transfer model to determine radiative effects due to changes in two natural aerosol sources: landscape fire and biogenic SOA. We find that interannual variability in the simulated global natural aerosol radiative effect (RE) is negatively related to the global temperature anomaly. The magnitude of global aerosol-climate feedback (sum of DRE and AIE) is estimated to be -0.15 Wm-2 K-1 for landscape fire aerosol and -0.06 Wm-2 K-1 for biogenic SOA. These feedbacks are comparable in magnitude, but opposite in sign to the snow albedo feedback, highlighting the need for natural aerosol feedbacks to

Aerosol physical and optical properties in the Eastern Mediterranean Basin, Crete, from Aerosol Robotic Network data

Directory of Open Access Journals (Sweden)

A. Fotiadi

2006-01-01

Full Text Available In this study, we investigate the aerosol optical properties, namely aerosol extinction optical thickness (AOT, Angström parameter and size distribution over the Eastern Mediterranean Basin, using spectral measurements from the recently established FORTH (Foundation for Research and Technology-Hellas AERONET station in Crete, for the two-year period 2003–2004. The location of the FORTH-AERONET station offers a unique opportunity to monitor aerosols from different sources. Maximum values of AOT are found primarily in spring, which together with small values of the Angström parameter indicate dust transported from African deserts, whereas the minimum values of AOT occur in winter. In autumn, large AOT values observed at near-infrared wavelengths arise also from dust transport. In summer, large AOT values at ultraviolet (340 nm and visible wavelengths (500 nm, together with large values of the Angström parameter, are associated with transport of fine aerosols of urban/industrial and biomass burning origin. The Angström parameter values vary on a daily basis within the range 0.05–2.20, and on a monthly basis within the range 0.68–1.9. This behaviour, together with broad frequency distributions and back-trajectory analyses, indicates a great variety of aerosol types over the study region including dust, urban-industrial and biomass-burning pollution, and maritime, as well as mixed aerosol types. Large temporal variability is observed in AOT, Angström parameter, aerosol content and size. The fine and coarse aerosol modes persist throughout the year, with the coarse mode dominant except in summer. The highest values of AOT are related primarily to southeasterly winds, associated with coarse aerosols, and to a less extent to northwesterly winds associated with fine aerosols. The results of this study show that the FORTH AERONET station in Crete is well suited for studying the transport and mixing of different types of aerosols from a variety

Basics concepts and clinical applications of oxygen-enhanced MR imaging

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Hatabu, Hiroto

2007-01-01

Oxygen-enhanced MR imaging is a new technique, and its physiological significance has not yet been fully elucidated. This review article covers (1) the theory of oxygen enhancement and its relationship with respiratory physiology; (2) design for oxygen-enhanced MR imaging sequencing; (3) a basic study of oxygen-enhanced MR imaging in animal models and humans; (4) a clinical study of oxygen-enhanced MR imaging; and (5) a comparison of advantages and disadvantages of this technique with those of hyperpolarized noble gas MR ventilation imaging. Oxygen-enhanced MR imaging provides not only the ventilation-related, but also respiration-related information. Oxygen-enhanced MR imaging has the potential to replace nuclear medicine studies for the identification of regional pulmonary function, and many investigators are now attempting to adapt this technique for routine clinical studies. We believe that further basic studies as well as clinical applications of this new technique will define the real significance of oxygen-enhanced MR imaging for the future of pulmonary functional imaging and its usefulness for diagnostic radiology and pulmonary medicine

Students' Conceptions of Function Transformation in a Dynamic Mathematical Environment

Science.gov (United States)

Daher, Wajeeh; Anabousy, Ahlam

2015-01-01

The study of function transformations helps students understand the function concept which is a basic and main concept in mathematics, but this study is problematic to school students as well as college students, especially when transformations are performed on non-basic functions. The current research tried to facilitate grade 9 students'…

Aerosol volatility in a boreal forest environment

Science.gov (United States)

Häkkinen, S. A. K.; ńijälä, M.; Lehtipalo, K.; Junninen, H.; Virkkula, A.; Worsnop, D. R.; Kulmala, M.; Petäjä, T.; Riipinen, I.

2012-04-01

Climate and health effects of atmospheric aerosols are determined by their properties such as their chemical composition. Aerosol chemical composition can be studied indirectly by measuring volatility of aerosol particles. The volatility of submicron aerosol particles (20-500 nm) was studied in a boreal forest site at SMEAR II (Station for Measuring Ecosystem-Atmosphere Relations II) station (Vesala et al., 1998) in Hyytiälä, Finland, during 01/2008-05/2010. The instrument used for the measurements was VDMPS (Volatility Differential Mobility Particle Sizer), which consists of two separate instruments: DMPS (Differential Mobility Particle Sizer, Aalto et al., 2001) and TD (Thermodenuder, Wehner et al., 2002). Aerosol evaporation was examined by heating the aerosol and comparing the total aerosol mass before and after heating. In the VDMPS system ambient aerosol sample was heated up to temperatures ranging from 80 °C to 280 °C. The higher the heating temperature was the more aerosol material was evaporated. There was a non-volatile residual present in aerosol particles when heated up to 280 °C. This residual explained (20±8)% of the total aerosol mass. Aerosol non-volatile mass fraction was highest during winter and smallest during summer months. The role of black carbon in the observed non-volatile residual was determined. Black carbon explained 40 to 90% of the non-volatile mass. Especially during colder seasons noticeable amount of non-volatile material, something else than black carbon, was observed. According to Kalberer et al. (2004) some atmospheric organic species can form polymers that have high evaporation temperatures. Also low-volatile organic salts may contribute to the non-volatile aerosol (Smith et al., 2010). Aerosol mass composition measured directly with AMS (Aerosol Mass Spectrometer, Jayne et al., 2000) was analyzed in order to examine the properties of the non-volatile material (other than black carbon). The AMS measurements were performed

A new experimental facility for studying aerosol sampling in workplace environments

International Nuclear Information System (INIS)

Fauvel, S.; Witstchger, O.

2000-01-01

The european council directive 96/29/EURATOM requires its implementation into national regulations. This directive lays down basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiations. This directive allows to use aerosol characteristics (particle size distribution, airborne concentration, morphology and chemical composition) measured in workplace to assess the effective radiation dose of workers resulting from the intake by inhalation of airborne radionuclides. Tests of performances of instruments used for the health-related sampling of particles in workplace are usually carried out in a wind tunnel or a calm air chamber. In these test conditions, instruments are exposed to uniform wind and steady homogeneous aerosol. In a real workplace situation, these instruments are usually exposed to highly non-uniform airflows and local emissions of particles. Moreover, it is not clear how differences in airflow pattern, proximity of the localised contamination source, worker location or activity would affect the personal/static measurement ratio. The objective of our experimental work is to investigate the relevant parameters that affect the aerosol characteristics in the microenvironment of a worker (including breathing zone) and in the workplace. The first part of that study was to design and built an experimental room CEPIA (french acronym for room for studying personal and area samplers). The ventilated chamber (volume 36 m 3 ) is equipped with an air delivery system to insure different ventilation patterns and flowrates. The CEPIA chamber should offer possibilities for performing experiments in situations representing a workplace environment, with airflows and aerosol parameters well controlled and characterised. (authors)

PRONET: Basic concepts of a system of Artificial Intelligence

Directory of Open Access Journals (Sweden)

S. Lasai

1999-12-01

Full Text Available In the work are expounded the principles and basic elements of a system of artificial intelligence. Knowledge representation develops according to the method settled for processing. A thing, a phenomenon can be determined or established by more modules subject to their state as well as the links and relations between them. The system creates a set of blocks (modules for which the concurrent work is pre- established. The volume of knowledge can be also increased without increasing the number of blocks.

Basic accelerator optics

CERN Document Server

CERN. Geneva. Audiovisual Unit

1985-01-01

A complete derivation, from first principles, of the concepts and methods applied in linear accelerator and beamline optics will be presented. Particle motion and beam motion in systems composed of linear magnets, as well as weak and strong focusing and special insertions are treated in mathematically simple terms, and design examples for magnets and systems are given. This series of five lectures is intended to provide all the basic tools required for the design and operation of beam optical systems.

Microphysical and chemical characteristics of near-water aerosol over White and Kara Seas

Science.gov (United States)

Terpugova, S. A.; Polkin, V. V.; Panchenko, M. V.; Golobokova, L. P.; Kozlov, V. S.; Shmargunov, V. P.; Shevchenko, V. P.; Lisitzin, A. P.

2009-04-01

undergo anthropogenic pollution through the atmospheric channels and are under permanent anthropogenic loading. They are coastal regions of Dvina Gulf and river Severnaya Dvina mouth, Kandalaksha Bay (near to the river Kandalaksha mouth), as well as coastal regions of Kola Peninsula. The work was supported in part by the Program of basic researches of Presidium RAS No. 17 "Basic problems of oceanology: physics, geology, biology, ecology", the project "Investigations of the properties and regularities of variability of atmospheric aerosol over ocean".

Basic Emotions: A Reconstruction

Science.gov (United States)

Mason, William A.; Capitanio, John P.

2016-01-01

Emotionality is a basic feature of behavior. The argument over whether the expression of emotions is based primarily on culture (constructivism, nurture) or biology (natural forms, nature) will never be resolved because both alternatives are untenable. The evidence is overwhelming that at all ages and all levels of organization, the development of emotionality is epigenetic: The organism is an active participant in its own development. To ascribe these effects to “experience” was the best that could be done for many years. With the rapid acceleration of information on how changes in organization are actually brought about, it is a good time to review, update, and revitalize our views of experience in relation to the concept of basic emotion. PMID:27110280

Electrochemistry. The basics, with examples

Energy Technology Data Exchange (ETDEWEB)

Lefrou, Christine [LEPMI, Saint Martin d' Heres (France); Poignet, Jean-Claude; Fabry, Pierre

2012-07-01

This book offers original and new approaches to the teaching of electrochemical concepts, principles and applications. Throughout the text the authors provide a balanced coverage of the thermodynamic and kinetic processes at the heart of electrochemical systems. The first half of the book outlines fundamental concepts appropriate to undergraduate students and the second half gives an in-depth account of electrochemical systems suitable for experienced scientists and course lecturers. Concepts are clearly explained and mathematical treatments are kept to a minimum or reported in appendices. This book features: 1. Questions and answers for self-assessment 2. Basic and advanced level numerical descriptions. 3. Illustrated electrochemistry applications This book is accessible to both novice and experienced electrochemists and supports a deep understanding of the fundamental principles and laws of electrochemistry.

Aerosol characterization over the southeastern United States using high-resolution aerosol mass spectrometry: spatial and seasonal variation of aerosol composition and sources with a focus on organic nitrates

Science.gov (United States)

Xu, L.; Suresh, S.; Guo, H.; Weber, R. J.; Ng, N. L.

2015-07-01

on the HR-ToF-AMS measurements, we estimate that the nitrate functionality from organic nitrates contributes 63-100 % to the total measured nitrates in summer. Furthermore, the contribution of organic nitrates to total OA is estimated to be 5-12 % in summer, suggesting that organic nitrates are important components in the ambient aerosol in the southeastern USA. The spatial distribution of OA is investigated by comparing simultaneous HR-ToF-AMS measurements with ACSM measurements at two different sampling sites. OA is found to be spatially homogeneous in summer due possibly to stagnant air mass and a dominant amount of regional secondary organic aerosol (SOA) in the southeastern USA. The homogeneity is less in winter, which is likely due to spatial variation of primary emissions. We observe that the seasonality of OA concentration shows a clear urban/rural contrast. While OA exhibits weak seasonal variation in the urban sites, its concentration is higher in summer than winter for rural sites. This observation from our year-long measurements is consistent with 14 years of organic carbon (OC) data from the SouthEastern Aerosol Research and Characterization (SEARCH) network. The comparison between short-term measurements with advanced instruments and long-term measurements of basic air quality indicators not only tests the robustness of the short-term measurements but also provides insights in interpreting long-term measurements. We find that OA factors resolved from PMF analysis on HR-ToF-AMS measurements have distinctly different diurnal variations. The compensation of OA factors with different diurnal trends is one possible reason for the repeatedly observed, relatively flat OA diurnal profile in the southeastern USA. In addition, analysis of long-term measurements shows that the correlation between OC and sulfate is substantially stronger in summer than winter. This seasonality could be partly due to the effects of sulfate on isoprene SOA formation as revealed by

Ambient Observations of Aerosols, Novel Aerosol Structures, And Their Engineering Applications

Science.gov (United States)

Beres, Nicholas D.

The role of atmospheric aerosols remains a crucial issue in understanding and mitigating climate change in our world today. These particles influence the Earth by altering the Earth's delicate radiation balance, human health, and visibility. In particular, black carbon particulate matter remains the key driver in positive radiative forcing (i.e., warming) due to aerosols. Produced from the incomplete combustion of hydrocarbons, these compounds can be found in many different forms around the globe. This thesis provides an overview of three research topics: (1) the ambient characterization of aerosols in the Northern Indian Ocean, measurement techniques used, and how these aerosols influence local, regional, and global climate; (2) the exploration of novel soot superaggregate particles collected in the Northern Indian Ocean and around the globe and how the properties of these particles relate to human health and climate forcing; and (3) how aerogelated soot can be produced in a novel, one-step method utilizing an inverted flame reactor and how this material could be used in industrial settings.

Influences of in-cloud aerosol scavenging parameterizations on aerosol concentrations and wet deposition in ECHAM5-HAM

Directory of Open Access Journals (Sweden)

B. Croft

2010-02-01

Full Text Available A diagnostic cloud nucleation scavenging scheme, which determines stratiform cloud scavenging ratios for both aerosol mass and number distributions, based on cloud droplet, and ice crystal number concentrations, is introduced into the ECHAM5-HAM global climate model. This scheme is coupled with a size-dependent in-cloud impaction scavenging parameterization for both cloud droplet-aerosol, and ice crystal-aerosol collisions. The aerosol mass scavenged in stratiform clouds is found to be primarily (>90% scavenged by cloud nucleation processes for all aerosol species, except for dust (50%. The aerosol number scavenged is primarily (>90% attributed to impaction. 99% of this impaction scavenging occurs in clouds with temperatures less than 273 K. Sensitivity studies are presented, which compare aerosol concentrations, burdens, and deposition for a variety of in-cloud scavenging approaches: prescribed fractions, a more computationally expensive prognostic aerosol cloud processing treatment, and the new diagnostic scheme, also with modified assumptions about in-cloud impaction and nucleation scavenging. Our results show that while uncertainties in the representation of in-cloud scavenging processes can lead to differences in the range of 20–30% for the predicted annual, global mean aerosol mass burdens, and near to 50% for accumulation mode aerosol number burden, the differences in predicted aerosol mass concentrations can be up to one order of magnitude, particularly for regions of the middle troposphere with temperatures below 273 K where mixed and ice phase clouds exist. Different parameterizations for impaction scavenging changed the predicted global, annual mean number removal attributed to ice clouds by seven-fold, and the global, annual dust mass removal attributed to impaction by two orders of magnitude. Closer agreement with observations of black carbon profiles from aircraft (increases near to one order of magnitude for mixed phase clouds

A study of the attachment of thoron decay products to aerosols using an aerosol centrifuge

International Nuclear Information System (INIS)

Balakrishnan, V.

1979-01-01

The physical attachment of radioactive decay products (particulate, not gas) to polydisperse fluorescein aerosal particles in two size ranges 0.1 μM-0.33 μM radius and 0.25 μM-1.35 μM radius has been studied under dynamic conditions with a view to find the fraction of thoron decay products attached to the aerosals and the particle size distribution of the host aerosols in the atmosphere of uranium mines. The experimental set-up and procedure are described. An aerosol cloud of fluorescein was introduced into a reaction chamber containing a steady source of thoron and decay products were allowed to interact and attach to the aerosols in the chamber. To simulate conditions normally encountered in uranium mining and milling operations, the concentration of aerosol particles was kept high as compared to the number of decay products. The Lovelace Aerosol Particle Separator, which is an advanced, continuous centrifugal aerosol separator, was used to sample and separate the tagged aerosols into various size groups. The radioactivity associated with each group was determined. The results show the same dependence of attachment of decay products on the size of aerosol particles as predicted by the diffusion theory proposed by Lassen and Rau (1960), even though the experimental conditions of the present study do not conform to those required to satisfy the above mentioned diffusion theory. The method employed in this work to study attachment is reproducible and simple and can be adopted in uranium and thorium mines and associated processing industries. (M.G.B.)

A characterization of Arctic aerosols on the basis of aerosol optical depth and black carbon measurements

Directory of Open Access Journals (Sweden)

R. S. Stone

2014-06-01

Full Text Available Abstract Aerosols, transported from distant source regions, influence the Arctic surface radiation budget. When deposited on snow and ice, carbonaceous particles can reduce the surface albedo, which accelerates melting, leading to a temperature-albedo feedback that amplifies Arctic warming. Black carbon (BC, in particular, has been implicated as a major warming agent at high latitudes. BC and co-emitted aerosols in the atmosphere, however, attenuate sunlight and radiatively cool the surface. Warming by soot deposition and cooling by atmospheric aerosols are referred to as “darkening” and “dimming” effects, respectively. In this study, climatologies of spectral aerosol optical depth AOD (2001–2011 and Equivalent BC (EBC (1989–2011 from three Arctic observatories and from a number of aircraft campaigns are used to characterize Arctic aerosols. Since the 1980s, concentrations of BC in the Arctic have decreased by more than 50% at ground stations where in situ observations are made. AOD has increased slightly during the past decade, with variations attributed to changing emission inventories and source strengths of natural aerosols, including biomass smoke and volcanic aerosol, further influenced by deposition rates and airflow patterns.

Global two-channel AVHRR aerosol climatology: effects of stratospheric aerosols and preliminary comparisons with MODIS and MISR retrievals

International Nuclear Information System (INIS)

Geogdzhayev, Igor V.; Mishchenko, Michael I.; Liu Li; Remer, Lorraine

2004-01-01

We present an update on the status of the global climatology of the aerosol column optical thickness and Angstrom exponent derived from channel-1 and -2 radiances of the Advanced Very High Resolution Radiometer (AVHRR) in the framework of the Global Aerosol Climatology Project (GACP). The latest version of the climatology covers the period from July 1983 to September 2001 and is based on an adjusted value of the diffuse component of the ocean reflectance as derived from extensive comparisons with ship sun-photometer data. We use the updated GACP climatology and Stratospheric Aerosol and Gas Experiment (SAGE) data to analyze how stratospheric aerosols from major volcanic eruptions can affect the GACP aerosol product. One possible retrieval strategy based on the AVHRR channel-1 and -2 data alone is to infer both the stratospheric and the tropospheric aerosol optical thickness while assuming fixed microphysical models for both aerosol components. The second approach is to use the SAGE stratospheric aerosol data in order to constrain the AVHRR retrieval algorithm. We demonstrate that the second approach yields a consistent long-term record of the tropospheric aerosol optical thickness and Angstrom exponent. Preliminary comparisons of the GACP aerosol product with MODerate resolution Imaging Spectrometer (MODIS) and Multiangle Imaging Spectro-Radiometer aerosol retrievals show reasonable agreement, the GACP global monthly optical thickness being lower than the MODIS one by approximately 0.03. Larger differences are observed on a regional scale. Comparisons of the GACP and MODIS Angstrom exponent records are less conclusive and require further analysis

Laser-Induced Breakdown Spectroscopy (LIBS) in a Novel Molten Salt Aerosol System.

Science.gov (United States)

Williams, Ammon N; Phongikaroon, Supathorn

2017-04-01

In the pyrochemical separation of used nuclear fuel (UNF), fission product, rare earth, and actinide chlorides accumulate in the molten salt electrolyte over time. Measuring this salt composition in near real-time is advantageous for operational efficiency, material accountability, and nuclear safeguards. Laser-induced breakdown spectroscopy (LIBS) has been proposed and demonstrated as a potential analytical approach for molten LiCl-KCl salts. However, all the studies conducted to date have used a static surface approach which can lead to issues with splashing, low repeatability, and poor sample homogeneity. In this initial study, a novel molten salt aerosol approach has been developed and explored to measure the composition of the salt via LIBS. The functionality of the system has been demonstrated as well as a basic optimization of the laser energy and nebulizer gas pressure used. Initial results have shown that this molten salt aerosol-LIBS system has a great potential as an analytical technique for measuring the molten salt electrolyte used in this UNF reprocessing technology.

AEROSOL AND GAS MEASUREMENT

Science.gov (United States)

Measurements provide fundamental information for evaluating and managing the impact of aerosols on air quality. Specific measurements of aerosol concentration and their physical and chemical properties are required by different users to meet different user-community needs. Befo...

Fundamental concepts of mathematics

CERN Document Server

Goodstein, R L

Fundamental Concepts of Mathematics, 2nd Edition provides an account of some basic concepts in modern mathematics. The book is primarily intended for mathematics teachers and lay people who wants to improve their skills in mathematics. Among the concepts and problems presented in the book include the determination of which integral polynomials have integral solutions; sentence logic and informal set theory; and why four colors is enough to color a map. Unlike in the first edition, the second edition provides detailed solutions to exercises contained in the text. Mathematics teachers and people

Comprehensive Airborne in Situ Characterization of Atmospheric Aerosols: From Angular Light Scattering to Particle Microphysics

Science.gov (United States)

Espinosa, W. Reed

A comprehensive understanding of atmospheric aerosols is necessary both to understand Earth's climate as well as produce skillful air quality forecasts. In order to advance our understanding of aerosols, the Laboratory for Aerosols, Clouds and Optics (LACO) has recently developed the Imaging Polar Nephelometer instrument concept for the in situ measurement of aerosol scattering properties. Imaging Nephelometers provide measurements of absolute phase function and polarized phase function over a wide angular range, typically 3 degrees to 177 degrees, with an angular resolution smaller than one degree. The first of these instruments, the Polarized Imaging Nephelometer (PI-Neph), has taken part in five airborne field experiments and is the only modern aerosol polar nephelometer to have flown aboard an aircraft. A method for the retrieval of aerosol optical and microphysical properties from I-Neph measurements is presented and the results are compared with existing measurement techniques. The resulting retrieved particle size distributions agree to within experimental error with measurements made by commercial optical particle counters. Additionally, the retrieved real part of the refractive index is generally found to be within the predicted error of 0.02 from the expected values for three species of humidified salt particles, whose refractive index is well established. A synopsis is then presented of aerosol scattering measurements made by the PI-Neph during the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) and the Deep Convection Clouds and Chemistry (DC3) field campaigns. To better summarize these extensive datasets a novel aerosol classification scheme is developed, making use of ancillary data that includes gas tracers, chemical composition, aerodynamic particle size and geographic location, all independent of PI-Neph measurements. Principal component analysis (PCA) is then used to reduce the

Teaching Basic Probability in Undergraduate Statistics or Management Science Courses

Science.gov (United States)

Naidu, Jaideep T.; Sanford, John F.

2017-01-01

Standard textbooks in core Statistics and Management Science classes present various examples to introduce basic probability concepts to undergraduate business students. These include tossing of a coin, throwing a die, and examples of that nature. While these are good examples to introduce basic probability, we use improvised versions of Russian…

Importance of aerosol non-sphericity in estimating aerosol radiative forcing in Indo-Gangetic Basin.

Science.gov (United States)

Srivastava, Parul; Dey, Sagnik; Srivastava, Atul Kumar; Singh, Sachchidanand; Mishra, S K; Tiwari, Suresh

2017-12-01

Aerosols are usually presumed spherical in shape while estimating the direct radiative forcing (DRF) using observations or in the models. In the Indo-Gangetic Basin (IGB), a regional aerosol hotspot where dust is a major aerosol species and has been observed to be non-spherical in shape, it is important to test the validity of this assumption. We address this issue using measured chemical composition at megacity Delhi, a representative site of the western IGB. Based on the observation, we choose three non-spherical shapes - spheroid, cylinder and chebyshev, and compute their optical properties. Non-spherical dust enhances aerosol extinction coefficient (β ext ) and single scattering albedo (SSA) at visible wavelengths by >0.05km -1 and >0.04 respectively, while it decreases asymmetry parameter (g) by ~0.1. Accounting non-sphericity leads top-of-the-atmosphere (TOA) dust DRF to more cooling due to enhanced backscattering and increases surface dimming due to enhanced β ext . Outgoing shortwave flux at TOA increases by up to 3.3% for composite aerosols with non-spherical dust externally mixed with other spherical species. Our results show that while non-sphericity needs to be accounted for, choice of shape may not be important in estimating aerosol DRF in the IGB. Copyright © 2017 Elsevier B.V. All rights reserved.

Direct measurement of aerosol shape factors

International Nuclear Information System (INIS)

Zeller, W.

1983-12-01

The dynamic shape factor whereas the coagulation shape factor is an average over the total examined size range. The experiments have shown that the results of experiments with a certain aerosol system cannot be transferred to other aerosol systems without further consideration. The outer shape of particles of a certain size depends on the specific properties of the material as well as on the experimental conditions during the aerosol generation. For both aerosol systems examined the mean dynamic shape factor, averaged over the total examined size range, agrees roughly with the coagulation shape factor. (Description of aerosol centrifuge and of differential mobility analyzer). (orig./HP) [de

Basic concepts on threat, vulnerability and risk associated to a process of massive use of gaseous fuels

International Nuclear Information System (INIS)

Ospina G, J.A.

1998-01-01

The massive use of gaseous fuels, natural gas and liquefied gas of the oil or G.L.P., demands the implementation and complex technologies utilization in each one of the technical activities operative that transportation, distribution and consumption of these fuels requires, in order to accomplish each one of they in the form most efficient and possible insurance. Natural phenomena (earthquakes, landslides) and technical phenomena and caused by the man (terrorism, not appropriate designs of transportation and distribution net, wrong manipulation of the gas equipment) represent a latent danger for the distributors as well as for the users of the gas, generating a threat, of large proportions, for the normal development of the program of massive use of the gas, in any geographical environment where this is implemented. In this article are described the disaster concepts, threat, vulnerability and risk and the form as are related to the project of massive use of the gas, basically to transportation areas, distribution and final use

Basic concepts of Density Functional Theory: Electronic structure calculation

International Nuclear Information System (INIS)

Sharma, B. Indrajit

2016-01-01

We are looking for a material which possesses the required properties as demanded for technological applications. For this we have to repeat the preparation of the appropriate materials and its characterizations. So, before proceeding to experiments, one can study on computer generated structure and predict the properties of the desired material. To do this, a concept of Density Functional Theory comes out. (paper)

Climate forcing by anthropogenic aerosols

Energy Technology Data Exchange (ETDEWEB)

Charlson, R J; Schwartz, S E; Hales, J M; Cess, R D; Coakley, Jr, J A; Hansen, J E; Hofmann, D J [University of Washington, Seattle, WA (USA). Inst. for Environmental Studies, Dept. of Atmospheric Sciences

1992-01-24

Although long considered to be of marginal importance to global climate change, tropospheric aerosol contributes substantially to radiative forcing, and anthropogenic sulfate aerosol in particular has imposed a major perturbation to this forcing. Both the direct scattering of short wavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate aerosol particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square metre, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the aerosol forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. Aerosol effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of aerosol climate forcing and on the controlling chemical and physical processes. 73 refs., 4 figs., 2 tabs.

Climate forcing by anthropogenic aerosols.

Science.gov (United States)

Charlson, R J; Schwartz, S E; Hales, J M; Cess, R D; Coakley, J A; Hansen, J E; Hofmann, D J

1992-01-24

Although long considered to be of marginal importance to global climate change, tropospheric aerosol contributes substantially to radiative forcing, and anthropogenic sulfate aerosol in particular has imposed a major perturbation to this forcing. Both the direct scattering of shortwavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate aerosol particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square meter, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the aerosol forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. Aerosol effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of aerosol climate forcing and on the controlling chemical and physical processes.

High Altitude Emissions of Black Carbon Aerosols: Potential Climate Implications

Science.gov (United States)

Satheesh, S. K.

2017-12-01

Synthesizing a series of ground-based and airborne measurements of aerosols over the Indian region during summer and pre-monsoon seasons have revealed the persistence of elevated absorbing aerosol layers over most of the Indian region; more than 50% of which located above clouds. Subsequent, in situ measurements of black carbon (BC) using high-altitude balloons, showed surprising layers with high concentrations in the middle and upper troposphere even at an altitude of 8 to 10 kms. Simultaneous measurements of the vertical thermal structure have shown localized warming due to BC absorption leading to large reduction in lapse rate and sharp temperature inversion, which in turn increases the atmospheric stability. This aerosol-induced stable layer is conducive for maintaining the black carbon layer longer at that level, leading thereby to further solar absorption and subsequently triggering dry convection. These observations support the `solar escalator' concept through which absorption-warming-convection cycles lead to self-lifting of BC to upper troposphere or even to lower stratosphere under favorable conditions in a matter of a few days. Employing an on-line regional chemistry transport model (WRF-Chem), incorporating aircraft emissions, it is shown that emissions from high-flying aircrafts as the most likely source of these elevated black carbon layers. These in-situ injected particles, produce significant warming of the thin air in those heights and lift these layers to even upper tropospheric/lower stratospheric heights, aided by the strong monsoonal convection occurring over the region, which are known to overshoot the tropical tropopause leading to injection of tropospheric air mass (along with its constituent aerosols) into the stratosphere, especially during monsoon season when the tropical tropopause layer is known to be thinnest. These simulations are further supported by the CALIPSO space-borne LIDAR derived extinction coefficient profiles. Based on

Papers of the 15. french congress on the aerosols CFA 99; Actes du 15. congres francais sur les aerosols CFA 99

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

This french congress on the aerosols took place in Paris the 8 and 9 december 1999. It was presented in four main themes: bio-aerosols and filtering; the aerosols metrology; the aerosols in the environment; aerosols physic and applications. Seven papers have been analyzed in INIS data base for their specific interest in the nuclear industry. They concern the aerosol capture simulation, the aerosols sampling in workplace environment, a ring-effect ion generator development for the charge and the neutralization of an aerosol cloud, the radon 222 characterization in a house, a particle re-entrainment, the electrical charge process of beta emitter radioactive aerosols, the simulation of air flows in many filters. The other ones are analyzed in the ETDE data base. (A.L.B.)

LEVEL OF KNOWLEDGE OF THE BASIC CONCEPTS OF PHYSICAL EVALUATION FOR THE PROFESSIONALS IN THE ACADEMICS OF THE CITY OF JOÃO PESSOA - PB

Directory of Open Access Journals (Sweden)

Rodrigo Benevides Ceriani

2005-10-01

Full Text Available The objective of this study is to verify the level of knowledge of the basic concepts of physical evaluation for the responsible professionals for this practice in the academies. He/she/you elapses of a traverse study, of field, with professionals that act in the area of Physical Evaluation, registered by CREF 10 - PB/RN. questionnaire of open and closed questions was Applied in 39 individuals. The statistics was applied of percentile of frequency through spreadsheet Excel. The results found that: 61,54% collect for the physical activity, being in 41,66% of the cases, 15 real; 69,23% don't include in the registration; 84,61% have knowledge of the one that is test; 61,54% of the one that it is to measure and 53,45% of the one that it is to evaluate. Three people were found without graduation in physical education, or in another course of superior level, acting in the area Conclusions: They still act inside of the academies, directly with the physical evaluation, professionals not graduated in physical education or in another course of superior level. Many appraisers don't possess the basic theoretical knowledge regarding the concepts that involve to test, to measure and to evaluate. In general it is collected by the physical evaluation, being most included in the customer's registration

The continuous field measurements of soluble aerosol compositions at the Taipei Aerosol Supersite, Taiwan

Science.gov (United States)

Chang, Shih-Yu; Lee, Chung-Te; Chou, Charles C.-K.; Liu, Shaw-Chen; Wen, Tian-Xue

The characteristics of ambient aerosols, affected by solar radiation, relative humidity, wind speed, wind direction, and gas-aerosol interaction, changed rapidly at different spatial and temporal scales. In Taipei Basin, dense traffic emissions and sufficient solar radiation for typical summer days favored the formation of secondary aerosols. In winter, the air quality in Taipei Basin was usually affected by the Asian continental outflows due to the long-range transport of pollutants carried by the winter monsoon. The conventional filter-based method needs a long time for collecting aerosols and analyzing compositions, which cannot provide high time-resolution data to investigate aerosol sources, atmospheric transformation processes, and health effects. In this work, the in situ ion chromatograph (IC) system was developed to provide 15-min time-resolution data of nine soluble inorganic species (Cl -, NO 2-, NO 3-, SO 42-, Na +, NH 4+, K +, Mg 2+ and Ca 2+). Over 89% of all particles larger than approximately 0.056 μm were collected by the in situ IC system. The in situ IC system is estimated to have a limit of detection lower than 0.3 μg m -3 for the various ambient ionic components. Depending on the hourly measurements, the pollutant events with high aerosol concentrations in Taipei Basin were associated with the local traffic emission in rush hour, the accumulation of pollutants in the stagnant atmosphere, the emission of industrial pollutants from the nearby factories, the photochemical secondary aerosol formation, and the long-range transport of pollutants from Asian outflows.

Aerosol Inlet Characterization Experiment Report

Energy Technology Data Exchange (ETDEWEB)

Bullard, Robert L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kuang, Chongai [Brookhaven National Lab. (BNL), Upton, NY (United States); Uin, Janek [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, Scott [Brookhaven National Lab. (BNL), Upton, NY (United States); Springston, Stephen R. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2017-05-01

The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility Aerosol Observation System inlet stack was characterized for particle penetration efficiency from 10 nm to 20 μm in diameter using duplicate scanning mobility particle sizers (10 nm-450 nm), ultra-high-sensitivity aerosol spectrometers (60 nm-μm), and aerodynamic particle sizers (0.5 μm-20 μm). Results show good model-measurement agreement and unit transmission efficiency of aerosols from 10 nm to 4 μm in diameter. Large uncertainties in the measured transmission efficiency exist above 4 μm due to low ambient aerosol signal in that size range.

Aerosols produced by evaporation of a uranium wire; Aerosols produits par evaporation d'un fil d'uranium

Energy Technology Data Exchange (ETDEWEB)

Morel, C [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1968-03-01

This work is devoted to the study of the aerosols formed when an uranium wire is evaporated in a normal or rarefied atmosphere, either with or without a drying agent. The heating of the wire can be either fast or slow. The first part is a study of aerosol production apparatus and of methods of measuring the aerosol. The second part presents the results obtained with various aerosols: the particles produced by the wire are less than one micron; during rapid heating, the granulometric distribution of the aerosol obeys a log-normal law; during slow heating, the distribution has two modes: one near 0.05 micron, the other close to 0.01 micron. (author) [French] Ce travail est consacre a l'etude des aerosols formes lors de l'evaporation d un fil d'uranium en atmosphere normale ou rarefiee en presence ou non de dessechant. Le chauffage du fil peut etre rapide ou lent. La premiere partie est une etude des appareils de production et des methodes de mesures de l'aerosol. La seconde partie consigne les resultats obtenus sur les differents aerosols: les particules emises par le fil sont inferieures au micron; lors d'un chauffage rapide, la repartition granulometrique de l'aerosol suit une loi log-normale; lors d un chauffage lent, la repartition presente deux modes: l'un voisin de 0.05 micron, l'autre voisin de 0.01 micron. (auteur)

Beschrijving van een verdampings-condensatie aerosol generator voor de produktie van submicron aerosol

NARCIS (Netherlands)

Feijt; A.*; Meulen; A.van der

1985-01-01

Dit rapport is een handleiding voor een bedrijfszeker, routinematig gebruik van een zgn. Evaporation-Condensation aerosol Conditioner. Met deze aerosol generatie apparatuur kunnen op stabiele, reproduceerbare manier zeer hoge concentraties (tot 1 miljoen deeltjes per cc) monodispers submicron

Aerosol Optical Properties Measured Onboard the Ronald H. Brown During ACE Asia as a Function of Aerosol Chemical Composition and Source Region

Science.gov (United States)

Quinn, P. K.; Coffman, D. J.; Bates, T. S.; Welton, E. J.; Covert, D. S.; Miller, T. L.; Johnson, J. E.; Maria, S.; Russell, L.; Arimoto, R.

2004-01-01

During the ACE Asia intensive field campaign conducted in the spring of 2001 aerosol properties were measured onboard the R/V Ronald H. Brown to study the effects of the Asian aerosol on atmospheric chemistry and climate in downwind regions. Aerosol properties measured in the marine boundary layer included chemical composition; number size distribution; and light scattering, hemispheric backscattering, and absorption coefficients. In addition, optical depth and vertical profiles of aerosol 180 deg backscatter were measured. Aerosol within the ACE Asia study region was found to be a complex mixture resulting from marine, pollution, volcanic, and dust sources. Presented here as a function of air mass source region are the mass fractions of the dominant aerosol chemical components, the fraction of the scattering measured at the surface due to each component, mass scattering efficiencies of the individual components, aerosol scattering and absorption coefficients, single scattering albedo, Angstrom exponents, optical depth, and vertical profiles of aerosol extinction. All results except aerosol optical depth and the vertical profiles of aerosol extinction are reported at a relative humidity of 55 +/- 5%. An over-determined data set was collected so that measured and calculated aerosol properties could be compared, internal consistency in the data set could be assessed, and sources of uncertainty could be identified. By taking into account non-sphericity of the dust aerosol, calculated and measured aerosol mass and scattering coefficients agreed within overall experimental uncertainties. Differences between measured and calculated aerosol absorption coefficients were not within reasonable uncertainty limits, however, and may indicate the inability of Mie theory and the assumption of internally mixed homogeneous spheres to predict absorption by the ACE Asia aerosol. Mass scattering efficiencies of non-sea salt sulfate aerosol, sea salt, submicron particulate organic

Glyoxal contribution to aerosols over Los Angeles

Science.gov (United States)

Balcerak, Ernie

2012-01-01

Laboratory and field studies have indicated that glyoxal (chemical formula OCHCHO), an atmospheric oxidation product of isoprene and aromatic compounds, may contribute to secondary organic aerosols in the atmosphere, which can block sunlight and affect atmospheric chemistry. Some aerosols are primary aerosols, emitted directly into the atmosphere, while others are secondary, formed through chemical reactions in the atmosphere. Washenfelder et al. describe in situ glyoxal measurements from Pasadena, Calif., near Los Angeles, made during summer 2010. They used three different methods to calculate the contribution of glyoxal to secondary atmospheric aerosol and found that it is responsible for 0-0.2 microgram per cubic meter, or 0-4%, of the secondary organic aerosol mass. The researchers also compared their results to those of a previous study that calculated the glyoxal contribution to aerosol for Mexico City. Mexico City had higher levels of organic aerosol mass from glyoxal. They suggest that the lower contribution of glyoxal to aerosol concentrations for Los Angeles may be due to differences in the composition or water content of the aerosols above the two cities. (Journal of Geophysical Research-Atmospheres, doi:10.1029/2011JD016314, 2011)

Aerosol processes relevant for the Netherlands

NARCIS (Netherlands)

Brugh, Aan de J.M.J.

2013-01-01

Particulate matter (or aerosols) are particles suspended in the atmosphere. Aerosols are believed to be the most important pollutant associated with increased human mortality and morbidity. Therefore, it is important to investigate the relationship between sources of aerosols (such as industry)

Climate implications of carbonaceous aerosols: An aerosol microphysical study using the GISS/MATRIX climate model

International Nuclear Information System (INIS)

Bauer, Susanne E.; Menon, Surabi; Koch, Dorothy; Bond, Tami; Tsigaridis, Kostas

2010-01-01

Recently, attention has been drawn towards black carbon aerosols as a likely short-term climate warming mitigation candidate. However the global and regional impacts of the direct, cloud-indirect and semi-direct forcing effects are highly uncertain, due to the complex nature of aerosol evolution and its climate interactions. Black carbon is directly released as particle into the atmosphere, but then interacts with other gases and particles through condensation and coagulation processes leading to further aerosol growth, aging and internal mixing. A detailed aerosol microphysical scheme, MATRIX, embedded within the global GISS modelE includes the above processes that determine the lifecycle and climate impact of aerosols. This study presents a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative forcing. Our best estimate for net direct and indirect aerosol radiative forcing change is -0.56 W/m 2 between 1750 and 2000. However, the direct and indirect aerosol effects are very sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative forcing change can vary between -0.32 to -0.75 W/m 2 depending on these carbonaceous particle properties. Assuming that sulfates, nitrates and secondary organics form a coating shell around a black carbon core, rather than forming a uniformly mixed particles, changes the overall net radiative forcing from a negative to a positive number. Black carbon mitigation scenarios showed generally a benefit when mainly black carbon sources such as diesel emissions are reduced, reducing organic and black carbon sources such as bio-fuels, does not lead to reduced warming.

Design e-learning with flipped learning model to improve layout understanding the concepts basic of the loop control structure

Science.gov (United States)

Handayani, D. P.; Sutarno, H.; Wihardi, Y.

2018-05-01

This study aimed in design and build e-learning with classroom flipped model to improve the concept of understanding of SMK students on the basic programming subject. Research and development obtained research data from survey questionnaire given to students of SMK class X RPL in SMK Negeri 2 Bandung and interviews to RPL productive teacher. Data also obtained from questionnaire of expert validation and students' assessment from e-learning with flipped classroom models. Data also obtained from multiple-choice test to measure improvements in conceptual understanding. The results of this research are: 1) Developed e- learning with flipped classroom model considered good and worthy of use by the average value of the percentage of 86,3% by media experts, and 85,5% by subjects matter experts, then students gave judgment is very good on e-learning either flipped classroom model with a percentage of 79,15% votes. 2) e-learning with classroom flipped models show an increase in the average value of pre-test before using e-learning 26.67 compared to the average value post-test after using e- learning at 63.37 and strengthened by the calculation of the index gains seen Increased understanding of students 'concepts by 50% with moderate criteria indicating that students' understanding is improving.

Effects of Geographic Information System on the Learning of Environmental Education Concepts in Basic Computer-Mediated Classrooms in Nigeria

Directory of Open Access Journals (Sweden)

Ayobami Gideon Adeleke

2017-12-01

Full Text Available This research paper specifically examined the impact of Geographic Information System (GIS integration in a learning method and on the performance and retention of Environmental Education (EE concepts in basic social studies. Non-equivalent experimental research design was employed. 126 pupils in four intact, computer-mediated classrooms were sampled. Instruments included Envi-Geo Info System (EGIS package and Environmental Information Achievement Test (EAT. The study found no significant effect of treatment on performances of participants in EGIS integrated treatment groups. No significant effect was found across the groups on pupils retention even though, treatment groups retention mean was higher than contemporaries. The study concluded that, adaptation of EGIS into sorted EE concepts will improve learning and might boost retention even in computer-mediated social studies classroom provided the use of GIS is made feasible in Nigeria and adopted into teaching-learning process. It recommended that stakeholders in Nigerian education system should foster workable strategies to improve teaching and learning and that, the use of GIS locally must be placed in the national education objectives. It is in the best interest of the people to learn the rudiments of personal safety, spatial development, incidental natural alerts, as well as preventions and solutions

Constraining the instantaneous aerosol influence on cloud albedo.

Science.gov (United States)

Gryspeerdt, Edward; Quaas, Johannes; Ferrachat, Sylvaine; Gettelman, Andrew; Ghan, Steven; Lohmann, Ulrike; Morrison, Hugh; Neubauer, David; Partridge, Daniel G; Stier, Philip; Takemura, Toshihiko; Wang, Hailong; Wang, Minghuai; Zhang, Kai

2017-05-09

Much of the uncertainty in estimates of the anthropogenic forcing of climate change comes from uncertainties in the instantaneous effect of aerosols on cloud albedo, known as the Twomey effect or the radiative forcing from aerosol-cloud interactions (RFaci), a component of the total or effective radiative forcing. Because aerosols serving as cloud condensation nuclei can have a strong influence on the cloud droplet number concentration ( N d ), previous studies have used the sensitivity of the N d to aerosol properties as a constraint on the strength of the RFaci. However, recent studies have suggested that relationships between aerosol and cloud properties in the present-day climate may not be suitable for determining the sensitivity of the N d to anthropogenic aerosol perturbations. Using an ensemble of global aerosol-climate models, this study demonstrates how joint histograms between N d and aerosol properties can account for many of the issues raised by previous studies. It shows that if the anthropogenic contribution to the aerosol is known, the RFaci can be diagnosed to within 20% of its actual value. The accuracy of different aerosol proxies for diagnosing the RFaci is investigated, confirming that using the aerosol optical depth significantly underestimates the strength of the aerosol-cloud interactions in satellite data.

Importance of Raman Lidar Aerosol Extinction Measurements for Aerosol-Cloud Interaction Studies

Directory of Open Access Journals (Sweden)

Han Zaw

2016-01-01

Full Text Available Using a UV Raman Lidar for aerosol extinction, and combining Microwave Radiometer derived Liquid Water Path (LWP with Multifilter Rotating Shadowband Radiometer derived Cloud Optical depth, to get cloud effective radius (Reff, we observe under certain specialized conditions, clear signatures of the Twomey Aerosol Indirect effect on cloud droplet properties which are consistent with the theoretical bounds. We also show that the measurement is very sensitive to how far the aerosol layer is from the cloud base and demonstrate that surface PM25 is far less useful. Measurements from both the DOE ARM site and new results at CCNY are presented.

On the implications of aerosol liquid water and phase separation for organic aerosol mass

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset contains data presented in the figures of the paper "On the implications of aerosol liquid water and phase separation for organic aerosol mass"...

Basic general concepts in the network analysis

Directory of Open Access Journals (Sweden)

Boja Nicolae

2004-01-01

Full Text Available This survey is concerned oneself with the study of those types of material networks which can be met both in civil engineering and also in electrotechnics, in mechanics, or in hydrotechnics, and of which behavior lead to linear problems, solvable by means of Finite Element Method and adequate algorithms. Here, it is presented a unitary theory of networks met in the domains mentioned above and this one is illustrated with examples for the structural networks in civil engineering, electric circuits, and water supply networks, but also planar or spatial mechanisms can be comprised in this theory. The attention is focused to make evident the essential proper- ties and concepts in the network analysis, which differentiate the networks under force from other types of material networks. To such a network a planar, connected, and directed or undirected graph is associated, and with some vector fields on the vertex set this graph is endowed. .

Background aerosol over the Himalayas and Tibetan Plateau: observed characteristics of aerosol mass loading

Science.gov (United States)

Liu, Bin; Cong, Zhiyuan; Wang, Yuesi; Xin, Jinyuan; Wan, Xin; Pan, Yuepeng; Liu, Zirui; Wang, Yonghong; Zhang, Guoshuai; Wang, Zhongyan; Wang, Yongjie; Kang, Shichang

2017-01-01

To investigate the atmospheric aerosols of the Himalayas and Tibetan Plateau (HTP), an observation network was established within the region's various ecosystems, including at the Ngari, Qomolangma (QOMS), Nam Co, and Southeastern Tibetan (SET) stations. In this paper we illustrate aerosol mass loadings by integrating in situ measurements with satellite and ground-based remote sensing datasets for the 2011-2013 period, on both local and large scales. Mass concentrations of these surface atmospheric aerosols were relatively low and varied with land cover, showing a general tendency of Ngari and QOMS (barren sites) > Nam Co (grassland site) > SET (forest site). Daily averages of online PM2.5 (particulates with aerodynamic diameters below 2.5 µm) at these sites were sequentially 18.2 ± 8.9, 14.5 ± 7.4, 11.9 ± 4.9 and 11.7 ± 4.7 µg m-3. Correspondingly, the ratios of PM2.5 to total suspended particles (TSP) were 27.4 ± 6.65, 22.3 ± 10.9, 37.3 ± 11.1 and 54.4 ± 6.72 %. Bimodal mass distributions of size-segregated particles were found at all sites, with a relatively small peak in accumulation mode and a more notable peak in coarse mode. Diurnal variations in fine-aerosol masses generally displayed a bi-peak pattern at the QOMS, Nam Co and SET stations and a single-peak pattern at the Ngari station, controlled by the effects of local geomorphology, mountain-valley breeze circulation and aerosol emissions. Dust aerosol content in PM2.1 samples gave fractions of 26 % at the Ngari station and 29 % at the QOMS station, or ˜ 2-3 times that of reported results at human-influenced sites. Furthermore, observed evidence confirmed the existence of the aerodynamic conditions necessary for the uplift of fine particles from a barren land surface. Combining surface aerosol data and atmospheric-column aerosol optical properties, the TSP mass and aerosol optical depth (AOD) of the Multi-angle Imaging Spectroradiometer (MISR) generally decreased as land cover changed from

Light-absorbing Aerosol Properties in the Kathmandu Valley during SusKat-ABC Field Campaign

Science.gov (United States)

Kim, S.; Yoon, S.; Kim, J.; Cho, C.; Jung, J.

2013-12-01

Light-absorbing aerosols, such as black carbon (BC), are major contributors to the atmospheric heating and the reduction of solar radiation reaching at the earth's surface. In this study, we investigate light-absorption and scattering properties of aerosols (i.e., BC mass concentration, aerosol solar-absorption/scattering efficiency) in the Kathmandu valley during Sustainable atmosphere for the Kathmandu valley (SusKat)-ABC campaign, from December 2012 to February 2013. Kathmandu City is among the most polluted cities in the world. However, there are only few past studies that provide basic understanding of air pollution in the Kathmandu Valley, which is not sufficient for designing effective mitigation measures (e.g., technological, financial, regulatory, legal and political measures, planning strategies). A distinct diurnal variation of BC mass concentration with two high peaks observed during wintertime dry monsoon period. BC mass concentration was found to be maximum around 09:00 and 20:00 local standard time (LST). Increased cars and cooking activities including substantial burning of wood and other biomass in the morning and in the evening contributed to high BC concentration. Low BC concentrations during the daytime can be explain by reduced vehicular movement and cooking activities. Also, the developmements of the boundary layer height and mountain-valley winds in the Kathmandu Valley paly a crucial role in the temproal variation of BC mass concentrations. Detailed radiative effects of light-absorbing aerosols will be presented.

Aerosol filtration with metallic fibrous filters

International Nuclear Information System (INIS)

Klein, M.; Goossens, W.R.A.

1983-01-01

The filtration efficiency of stainless steel fibrous filters (BEKIPOR porous mats and sintered webs) is determined using submicronic monodisperse polystyrene aerosols. Lasers spectrometers are used for the aerosol measurements. The parameters varied are the fiber diameter, the number of layers, the aerosol diameter and the superficial velocity. Two selected types of filters are tested with polydisperse methylene blue aerosols to determine the effect of bed loading on the filter performance and to test washing techniques for the regeneration of the filter

Infrared remote sensing of atmospheric aerosols; Apports du sondage infrarouge a l'etude des aerosols atmospheriques

Energy Technology Data Exchange (ETDEWEB)

Pierangelo, C

2005-09-15

The 2001 report from the Intergovernmental Panel on Climate Change emphasized the very low level of understanding of atmospheric aerosol effects on climate. These particles originate either from natural sources (dust, volcanic aerosols...) or from anthropogenic sources (sulfates, soot...). They are one of the main sources of uncertainty on climate change, partly because they show a very high spatio-temporal variability. Observation from space, being global and quasi-continuous, is therefore a first importance tool for aerosol studies. Remote sensing in the visible domain has been widely used to obtain a better characterization of these particles and their effect on solar radiation. On the opposite, remote sensing of aerosols in the infrared domain still remains marginal. Yet, not only the knowledge of the effect of aerosols on terrestrial radiation is needed for the evaluation of their total radiative forcing, but also infrared remote sensing provides a way to retrieve other aerosol characteristics (observations are possible at night and day, over land and sea). In this PhD dissertation, we show that aerosol optical depth, altitude and size can be retrieved from infrared sounder observations. We first study the sensitivity of aerosol optical properties to their micro-physical properties, we then develop a radiative transfer code for scattering medium adapted to the very high spectral resolution of the new generation sounder NASA-Aqua/AIRS, and we finally focus on the inverse problem. The applications shown here deal with Pinatubo stratospheric volcanic aerosol, observed with NOAA/HIRS, and with the building of an 8 year climatology of dust over sea and land from this sounder. Finally, from AIRS observations, we retrieve the optical depth at 10 {mu}m, the average altitude and the coarse mode effective radius of mineral dust over sea. (author)

DARE: a dedicated aerosols retrieval instrument

NARCIS (Netherlands)

Court, A.J.; Smorenburg, K.; Courrèges-Lacoste, G.B.; Visser, H.; Leeuw, G. de; Decae, R.

2004-01-01

Satellite remote sensing of aerosols is a largely unresolved problem. A dedicated instrument aimed at aerosols would be able to reduce the large uncertainties connected to this kind of remote sensing. TNO is performing a study of a space based instrument for aerosol measurements, together with the

Data assimilation of CALIPSO aerosol observations

Directory of Open Access Journals (Sweden)

T. T. Sekiyama

2010-01-01

Full Text Available We have developed an advanced data assimilation system for a global aerosol model with a four-dimensional ensemble Kalman filter in which the Level 1B data from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO were successfully assimilated for the first time, to the best of the authors' knowledge. A one-month data assimilation cycle experiment for dust, sulfate, and sea-salt aerosols was performed in May 2007. The results were validated via two independent observations: 1 the ground-based lidar network in East Asia, managed by the National Institute for Environmental Studies of Japan, and 2 weather reports of aeolian dust events in Japan. Detailed four-dimensional structures of aerosol outflows from source regions over oceans and continents for various particle types and sizes were well reproduced. The intensity of dust emission at each grid point was also corrected by this data assimilation system. These results are valuable for the comprehensive analysis of aerosol behavior as well as aerosol forecasting.

Operational aerosol and dust storm forecasting

International Nuclear Information System (INIS)

Westphal, D L; Curtis, C A; Liu, M; Walker, A L

2009-01-01

The U. S. Navy now conducts operational forecasting of aerosols and dust storms on global and regional scales. The Navy Aerosol Analysis and Prediction System (NAAPS) is run four times per day and produces 6-day forecasts of sulfate, smoke, dust and sea salt aerosol concentrations and visibility for the entire globe. The Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS (registered) ) is run twice daily for Southwest Asia and produces 3-day forecasts of dust, smoke, and visibility. The graphical output from these models is available on the Internet (www.nrlmry.navy.mil/aerosol/). The aerosol optical properties are calculated for each specie for each forecast output time and used for sea surface temperature (SST) retrieval corrections, regional electro-optical (EO) propagation assessments, and the development of satellite algorithms. NAAPS daily aerosol optical depth (AOD) values are compared with the Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) AOD values. Visibility forecasts are compared quantitatively with surface synoptic reports.

Multi-sensor cloud and aerosol retrieval simulator and remote sensing from model parameters - Part 2: Aerosols

Science.gov (United States)

Wind, Galina; da Silva, Arlindo M.; Norris, Peter M.; Platnick, Steven; Mattoo, Shana; Levy, Robert C.

2016-07-01

The Multi-sensor Cloud Retrieval Simulator (MCRS) produces a "simulated radiance" product from any high-resolution general circulation model with interactive aerosol as if a specific sensor such as the Moderate Resolution Imaging Spectroradiometer (MODIS) were viewing a combination of the atmospheric column and land-ocean surface at a specific location. Previously the MCRS code only included contributions from atmosphere and clouds in its radiance calculations and did not incorporate properties of aerosols. In this paper we added a new aerosol properties module to the MCRS code that allows users to insert a mixture of up to 15 different aerosol species in any of 36 vertical layers.This new MCRS code is now known as MCARS (Multi-sensor Cloud and Aerosol Retrieval Simulator). Inclusion of an aerosol module into MCARS not only allows for extensive, tightly controlled testing of various aspects of satellite operational cloud and aerosol properties retrieval algorithms, but also provides a platform for comparing cloud and aerosol models against satellite measurements. This kind of two-way platform can improve the efficacy of model parameterizations of measured satellite radiances, allowing the assessment of model skill consistently with the retrieval algorithm. The MCARS code provides dynamic controls for appearance of cloud and aerosol layers. Thereby detailed quantitative studies of the impacts of various atmospheric components can be controlled.In this paper we illustrate the operation of MCARS by deriving simulated radiances from various data field output by the Goddard Earth Observing System version 5 (GEOS-5) model. The model aerosol fields are prepared for translation to simulated radiance using the same model subgrid variability parameterizations as are used for cloud and atmospheric properties profiles, namely the ICA technique. After MCARS computes modeled sensor radiances equivalent to their observed counterparts, these radiances are presented as input to

Multi-Sensor Cloud and Aerosol Retrieval Simulator and Remote Sensing from Model Parameters . Part 2; Aerosols

Science.gov (United States)

Wind, Galina; Da Silva, Arlindo M.; Norris, Peter M.; Platnick, Steven; Mattoo, Shana; Levy, Robert C.

2016-01-01

The Multi-sensor Cloud Retrieval Simulator (MCRS) produces a simulated radiance product from any high-resolution general circulation model with interactive aerosol as if a specific sensor such as the Moderate Resolution Imaging Spectroradiometer (MODIS) were viewing a combination of the atmospheric column and land ocean surface at a specific location. Previously the MCRS code only included contributions from atmosphere and clouds in its radiance calculations and did not incorporate properties of aerosols. In this paper we added a new aerosol properties module to the MCRS code that allows users to insert a mixture of up to 15 different aerosol species in any of 36 vertical layers. This new MCRS code is now known as MCARS (Multi-sensor Cloud and Aerosol Retrieval Simulator). Inclusion of an aerosol module into MCARS not only allows for extensive, tightly controlled testing of various aspects of satellite operational cloud and aerosol properties retrieval algorithms, but also provides a platform for comparing cloud and aerosol models against satellite measurements. This kind of two-way platform can improve the efficacy of model parameterizations of measured satellite radiances, allowing the assessment of model skill consistently with the retrieval algorithm. The MCARS code provides dynamic controls for appearance of cloud and aerosol layers. Thereby detailed quantitative studies of the impacts of various atmospheric components can be controlled. In this paper we illustrate the operation of MCARS by deriving simulated radiances from various data field output by the Goddard Earth Observing System version 5 (GEOS-5) model. The model aerosol fields are prepared for translation to simulated radiance using the same model sub grid variability parameterizations as are used for cloud and atmospheric properties profiles, namely the ICA technique. After MCARS computes modeled sensor radiances equivalent to their observed counterparts, these radiances are presented as input to

Transportation Emissions: some basics

DEFF Research Database (Denmark)

Kontovas, Christos A.; Psaraftis, Harilaos N.

2016-01-01

transportation and especially carbon dioxide emissions are at the center stage of discussion by the world community through various international treaties, such as the Kyoto Protocol. The transportation sector also emits non-CO2 pollutants that have important effects on air quality, climate, and public health......Transportation is the backbone of international trade and a key engine driving globalization. However, there is growing concern that the Earth’s atmospheric composition is being altered by human activities, including transportation, which can lead to climate change. Air pollution from....... The main purpose of this chapter is to introduce some basic concepts that are relevant in the quest of green transportation logistics. First, we present the basics of estimating emissions from transportation activities, the current statistics and future trends, as well as the total impact of air emissions...

The impacts of aerosol loading, composition, and water uptake on aerosol extinction variability in the Baltimore–Washington, D.C. region