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Setting of Linear Analysis on Manifolds - Jurgen Eichhorn - Bog - Nova Science Publishers Inc - Plusbog.dk

Fixed Bed Reactors with Gradient Catalysts - Elena S Borisova - Bog - Nova Science Publishers Inc - Plusbog.dk

Fixed Bed Reactors with Gradient Catalysts - Elena S Borisova - Bog - Nova Science Publishers Inc - Plusbog.dk

High-energy catalytic processes operated in fixed bed reactors are widely used in many fields of chemical engineering, so the improvement of specific intensities of such processes to minimise the equipment size and related capital cost, to enhance the reliability is of great importance. The specific features of such processes are reactant concentration gradients through the bed length which may cause considerable temperature gradients in exo-endothermic reactions; therefore, the catalysts used for the existing and innovative high-energy catalytic processes must meet severe requirements. The catalytic processes in fixed bed reactors are rather complicated and usually include the chemical reactions, the processes of mass and heat transfer and reactant adsorption/desorption. As a result, a specially organised catalytic fixed bed with non-uniform properties (gradient catalysts) may appear more appropriate in some cases than the uniform one. At present, the ideas of gradient catalysts are used for creation the new type of after-burning catalysts, for microchannel reactors. In the theoretical investigation the attention is being increasingly focused on the complex approach based on the optimisation of heat and mass transfer and of the activity of the whole catalyst bed through the optimal bed packing, granule shape, distribution of the active component, heat conductivity etc., i.e. through creation of some optimal gradient medium for conducting the catalytic process. Fundamentals for optimisation of the spatial bed structure, in particular for optimisation of the active component distribution through the bed length, are developed intensively with regard to synthesis of new materials and creation of new methods for arranging reaction beds (for example, in microchannel reactors). The authors of the present book are the first who propose to use the variational approach for solving these problems, so they theoretically formulated the problem of a catalytic process optimisation by means of non-uniform spatial active sites distribution and obtained the analytic solutions for several cases

DKK 405.00
1

Method for Analysis of Transmission Lines Terminated by Nonlinear Loads - - Bog - Nova Science Publishers Inc - Plusbog.dk

Method for Analysis of Transmission Lines Terminated by Nonlinear Loads - - Bog - Nova Science Publishers Inc - Plusbog.dk

The main purpose of the present book is to propose a method for solving the mixed problem for transmission line systems reducing it to a neutral equation (or system) on the boundary. Arising non-linearities in the neutral systems are caused by non-linear characteristics of the RGCL-loads. In view of the applications we consider mainly periodic and oscillatory problems for loss-less transmission lines. We point out, however, that here we propose an extended procedure for reducing the mixed problem for lossless and lossy transmission lines. We introduce also an extension of Heaviside condition and this way we can consider the case of time-varying specific parameters-per-unit length resistance, conductance, inductance and capacitance. We find a solution of the obtained neutral equations by discovering operators whose fixed points in suitable function spaces are periodic or oscillatory solutions of the formulating problems. Using fixed point theorems for contractive mappings in uniform and metric spaces (proved by the author in the previous papers) we prove existence -- uniqueness results for periodic and oscillatory problems. We obtain also successive approximations of the solution with respect to a suitable family of pseudo-metrics and give an estimate of the rate of convergence. Although the question of finding the initial approximation is not trivial. We show that one can begin with a simple harmonic initial approximation. The rate of convergence depends on the parameters of the transmission lines and characteristics of the non-linear RCL-loads. Our conditions are applicable even in some cases to non-uniform transmission lines. Numerical examples demonstrate the applicability of the main results to design of circuits. It is easy to verify a system of inequalities between basic parameters without examining the proofs of the theorems.

DKK 722.00
1

Toward a Science of Clinical Psychology - - Bog - Nova Science Publishers Inc - Plusbog.dk

Geometric Properties & Problems of Thick Knots - Claus Ernst - Bog - Nova Science Publishers Inc - Plusbog.dk

How Crime in the United States Is Measured - Logan Rishard - Bog - Nova Science Publishers Inc - Plusbog.dk

How Crime in the United States Is Measured - Logan Rishard - Bog - Nova Science Publishers Inc - Plusbog.dk

Crime data collected through the Uniform Crime Reports (UCR), the National Incident-Based Reporting System (NIBRS), and the National Crime Victimisation Survey (NCVS) are used by Congress to inform policy decisions and allocate federal criminal justice funding to states. As such, it is important to understand how each program collects and reports crime data, and the limitations associated with the data. This book reviews (1) the history of the UCR, the NIBRS, and the NCVS; (2) the methods each program uses to collect crime data; and (3) the limitations of the data collected by each program. The book then compares the similarities and differences of UCR and NCVS data. It concludes by reviewing issues related to the NIBRS and the NCVS. The UCR represents the first effort to create a national, standardised measure of the incidence of crime. It was conceived as a way to measure the effectiveness of local law enforcement and to provide law enforcement with data that could be used to help fight crime. UCR data are now used extensively by researchers, government officials, and the media for research, policy, and planning purposes. The UCR also provides some of the most commonly cited crime statistics in the United States. The UCR reports offence and arrest data for 8 different Part I offences and arrest data for 21 different Part II offences. The NIBRS was developed by the Federal Bureau of Investigation to respond to the law enforcement community''s belief that the UCR needed to be updated to provide more in-depth data to meet the needs of law enforcement into the 21st century. The NIBRS collects data, including data on offence(s), offender(s), victim(s), arrestee(s), and any property involved in an offence, for 46 different Group A offences and 11 different Group B offences. Despite the more detailed crime data that the NIBRS can provide, nation-wide implementation of the program has been slow, for a variety of reasons, including cost considerations. The NCVS is the primary source of information on the characteristics of criminal victimisation, and on the number and types of crime not reported to law enforcement. The NCVS has four major objectives: (1) to develop detailed information about the victims and consequences of crime, (2) to estimate the number and types of crimes not reported to police, (3) to provide uniform measures of selected types of crimes, and (4) to permit comparisons over time and population type (e.g., urban, suburban, and rural). The NCVS asks respondents whether they have been the victim of rape and sexual assault, robbery, simple and aggravated assault, purse snatching/pick-pocketing, burglary, theft, or motor vehicle theft. In addition to collecting data on the number of victimisations, the NCVS gathers data on the details of each incident of victimisation.

DKK 514.00
1

Youth Gangs - - Bog - Nova Science Publishers Inc - Plusbog.dk

Youth Gangs - - Bog - Nova Science Publishers Inc - Plusbog.dk

Gang activity and related violence threaten public order in a diverse range of communities in the United States today. Congress has long recognised that this problem affects a number of issues of federal concern, and federal legislation has been introduced in the 110th Congress to address some aspects of the issue. Youth gangs have been an endemic feature of American urban life. They are well attested as early as the 18th century and have been a recurrent subject of concern since then. Contemporary views of the problem have been formed against the background of a significant adverse secular trend in gang activity during the last four decades. In particular, the rapid growth of gang membership, geographical dispersion, and criminal involvement during the violent crime epidemic; associated with the emergence of the crack cocaine market during the mid-1980s to the early 1990s; have intensified current concerns. The experience of those years continues to mark both patterns of gang activity and public policy responses toward them. Policy development and implementation in this area are be-devilled by discrepant uses of the term "gang" and the absence of uniform standards of statistical reporting. There are reasons for special care in the use of data on gangs and their activity. Without a standardised definition of what is meant by "gang", such as the age group or activities engaged in by its members, or standardised reporting among the state, local, tribal, and federal levels of government, it is difficult to target anti-gang initiatives and evaluate their effectiveness. According to a national gang survey, the most recent estimate indicates that there were about 760,000 gang members in 24,000 gangs in the United States in 2004. This book provides background information on the issue of youth gangs, including data on gangs and gang crime. It reviews existing anti-gang initiatives at the federal, state, and local levels, and describes some of the legislation proposed during the 110th Congress to address the gang problem, as well as some of the issues raised by those bills.

DKK 608.00
1

COPD & the Workplace - Jordan Minov - Bog - Nova Science Publishers Inc - Plusbog.dk

COPD & the Workplace - Jordan Minov - Bog - Nova Science Publishers Inc - Plusbog.dk

Chronic obstructive pulmonary disease (COPD) is a major cause of disability and is the fourth leading cause of death throughout the world. Although cigarette smoking is the major and best studied causative factor of COPD, there is consistent evidence that a substantial proportion of COPD cases cannot be explained by smoking. Other noxious particles and gases, such as workplace dusts, vapours, fumes or gases, indoor air pollution from burning biomass fuels during cooking foods and heating spaces, and air pollution in urban areas are important risk factors of COPD. According to collected data, 15-20% of COPD cases are likely to be caused or made worse by work; around 4,000 COPD deaths every year are related to workplace exposures, and 40% of COPD patients are below the retirement age. The development of COPD as a consequence of workplace exposure is a matter of growing interest and importance. There is no doubt that certain workplace exposures enhance the risk of COPD and may do so independently of or in concordance with cigarette smoking. The evidence is most coherent for work that entails exposure to coal, silica, welding fumes, cadmium fumes, cotton dust, farming dusts, grain dust and/or wood dust. The research found consistent associations between workplace exposures and COPD across a wide range of sectors, describing a nearly uniform pattern of exposure-response relationships. Based on the research, affected occupations include miners, construction workers, road workers, tunnel workers, welders, glass workers, metal workers, foundry workers, textile workers, farm laborers, wood workers, chemical workers, and rubber workers; in other words, a working population including millions and millions workers worldwide have been affected. It seems that occupational risk for COPD, although variable, is smaller compared with that of cigarette smoking. However, it affects a large proportion of the population and its contribution to the total burden of COPD cannot not be neglected. In addition, existing evidence indicates that workplace exposure may influence the course of COPD as factors with significant impacts on the progression and severity of the disease. As in the case of the workplace agents being causative factors of COPD, the mechanisms underlying this effect still are not fully understood. This monograph contains seven chapters which cover the most important aspects of this issue. It summarizes results of the studies performed in this area of research and conclusions based on them. This monograph also presents the author''s view regarding the influence of workplace exposures on the development and progression of COPD. In addition, it may be a basis for further research for better understanding of the association between COPD and workplace exposures.

DKK 1034.00
1

Child Welfare - Emilie Stoltzfus - Bog - Nova Science Publishers Inc - Plusbog.dk

Child Welfare - Emilie Stoltzfus - Bog - Nova Science Publishers Inc - Plusbog.dk

While child welfare programs are a primary responsibility of state and local governments, the federal government appropriates close to $7 billion annually to support these programs (primarily for foster care and adoption assistance) and states are required to meet certain federal policies in order to receive this funding. Child and Family Services Reviews (CFSRs) gauge state efforts and ability to achieve the primary goals of safety and permanence for children, and well-being for children and their families. The review is intended both to measure state compliance with federal child welfare policy and to strengthen and improve state child welfare programs. The Department of Health and Human Services (HHS) conducted the initial round of onsite reviews between March 2001 and March 2004. No state was found to be in substantial conformity with all of the outcomes and systems assessed. Some critics of the CFSR argue that while the outcomes reviewed are on target, the criteria established to determine state achievement of those outcomes may give misleading information about a state''s performance. Although much attention has focused on states'' uniform inability to meet all of the federal criteria, the reviews also showed certain relative strengths. States showed the greatest ability to ensure that children were not exposed to child abuse and neglect and remained safely in their homes whenever appropriate and possible, and in preserving their family relationships and connections. They had the most difficulty in achieving permanent and stable living arrangements for children, enhancing the capacity of families to meet the needs of their children and in seeing that appropriate mental and physical health services were available to children served. Information regarding ensuring provision of educational services to children was more mixed. In addition to reviewing outcomes, the CFSR assesses state compliance with federal child welfare policy by examining certain federally required systems. States were most likely to be found successful at operating a statewide information system; maintaining foster and adoptive parent licensing, training, recruitment and retention; and responding to community concerns. They were least likely to have a strong service array or case review system in place. Ratings of state quality assurance and training systems were more mixed. To avoid immediate assessment of penalties for failure to comply with federal policy, each state was required to develop a Program Improvement Plan (PIP). A PIP must address each one of the outcomes or systems with which a state was found to be out of substantial conformity and must describe the state''s specific plan for moving toward full conformity with federal policy. A few states have successfully completed their PIPS but most are still in the process of implementing them. The Children''s Bureau has begun planning for a second round of CFSRs and onsite reviews will likely begin in FY2006. This book describes the origins and design of CFSRs before turning to its primary discussion: state performance in the initial round of CFSRs.

DKK 687.00
1