Showing papers on "Literature survey published in 2003"
TL;DR: In this paper, the authors provide an up-to-date critical survey of still-and video-based face recognition research, and provide some insights into the studies of machine recognition of faces.
Abstract: As one of the most successful applications of image analysis and understanding, face recognition has recently received significant attention, especially during the past several years. At least two reasons account for this trend: the first is the wide range of commercial and law enforcement applications, and the second is the availability of feasible technologies after 30 years of research. Even though current machine recognition systems have reached a certain level of maturity, their success is limited by the conditions imposed by many real applications. For example, recognition of face images acquired in an outdoor environment with changes in illumination and/or pose remains a largely unsolved problem. In other words, current systems are still far away from the capability of the human perception system.This paper provides an up-to-date critical survey of still- and video-based face recognition research. There are two underlying motivations for us to write this survey paper: the first is to provide an up-to-date review of the existing literature, and the second is to offer some insights into the studies of machine recognition of faces. To provide a comprehensive survey, we not only categorize existing recognition techniques but also present detailed descriptions of representative methods within each category. In addition, relevant topics such as psychophysical studies, system evaluation, and issues of illumination and pose variation are covered.
6,384 citations
TL;DR: The technical feasibility of various low-cost adsorbents for heavy metal removal from contaminated water has been reviewed and it is evident from the literature survey of about 100 papers that low- cost adsorbent have demonstrated outstanding removal capabilities for certain metal ions as compared to activated carbon.
3,072 citations
TL;DR: This survey detected species-level paraphyly or polyphyly in 23% of 2319 assayed species, demonstrating this phenomenon to be statistically supported, taxonomically widespread, and far more common than generally recognized.
Abstract: ▪ Abstract Many uses of gene trees implicitly assume that nominal species are monophyletic in their alleles at the study locus. However, in well-sampled gene trees, certain alleles in one species may appear more closely related to alleles from different species than to other conspecific alleles. Such deviations from species-level monophyly have a variety of causes and may lead to erroneous evolutionary interpretations if undetected. The present paper describes the causes and consequences of these paraphyletic and polyphyletic patterns. It also provides a detailed literature survey of mitochondrial DNA studies on low-level animal phylogeny and phylogeography, results from which reveal the frequency of nonmonophyly and patterns of interpretation and sampling. This survey detected species-level paraphyly or polyphyly in 23% of 2319 assayed species, demonstrating this phenomenon to be statistically supported, taxonomically widespread, and far more common than generally recognized. Our findings call for increa...
2,025 citations
TL;DR: In this article, the authors summarized current thinking on technological change in the broader economics literature, surveys the growing economic literature on the interaction between technology and the environment, and explores the normative implications of these analyses.
Abstract: Environmental policy discussions increasingly focus on issues related to technological change This is partly because the environmental consequences of social activity are frequently affected by the rate and direction of technological change, and partly because environmental policy interventions can themselves create constraints and incentives that have significant effects on the path of technological progress This chapter summarizes current thinking on technological change in the broader economics literature, surveys the growing economic literature on the interaction between technology and the environment, and explores the normative implications of these analyses We begin with a brief overview of the economics of technological change, and then examine theory and empirical evidence on invention, innovation, and diffusion and the related literature on the effects of environmental policy on the creation of new, environmentally friendly technology We conclude with suggestions for further research on technological change and the environment
641 citations
TL;DR: Doctors should require strict indications for the use of spinal anesthetic procedures in patients receiving anticoagulant therapy, even if the incidence of spinal hematoma following this combination is low, and close monitoring of the neurological status of the patient is warranted.
Abstract: Spinal hematoma has been described in autopsies since 1682 and as a clinical diagnosis since 1867. It is a rare and usually severe neurological disorder that, without adequate treatment, often leads to death or permanent neurological deficit. Epidural as well as subdural and subarachnoid hematomas have been investigated. Some cases of subarachnoid spinal hematoma may present with symptoms similar to those of cerebral hemorrhage. The literature offers no reliable estimates of the incidence of spinal hematoma, perhaps due to the rarity of this disorder. In the present work, 613 case studies published between 1826 and 1996 have been evaluated, which represents the largest review on this topic to date. Most cases of spinal hematoma have a multifactorial etiology whose individual components are not all understood in detail. In up to a third of cases (29.7%) of spinal hematoma, no etiological factor can be identified as the cause of the bleeding. Following idiopathic spinal hematoma, cases related to anticoagulant therapy and vascular malformations represent the second and third most common categories. Spinal and epidural anesthetic procedures in combination with anticoagulant therapy represent the fifth most common etiological group and spinal and epidural anesthetic procedures alone represent the tenth most common cause of spinal hematoma. Anticoagulant therapy alone probably does not trigger spinal hemorrhage. It is likely that there must additionally be a "locus minoris resistentiae" together with increased pressure in the interior vertebral venous plexus in order to cause spinal hemorrhage. The latter two factors are thought to be sufficient to cause spontaneous spinal hematoma. Physicians should require strict indications for the use of spinal anesthetic procedures in patients receiving anticoagulant therapy, even if the incidence of spinal hematoma following this combination is low. If spinal anesthetic procedures are performed before, during, or after anticoagulant treatment, close monitoring of the neurological status of the patient is warranted. Time limits regarding the use of anticoagulant therapy before or after spinal anesthetic procedures have been proposed and are thought to be safe for patients. Investigation of the coagulation status alone does not necessarily provide an accurate estimate of the risk of hemorrhage. The most important measure for recognizing patients at high risk is a thorough clinical history. Most spinal hematomas are localized dorsally to the spinal cord at the level of the cervicothoracic and thoracolumbar regions. Subarachnoid hematomas can extend along the entire length of the subarachnoid space. Epidural and subdural spinal hematoma present with intense, knife-like pain at the location of the hemorrhage ("coup de poignard") that may be followed in some cases by a pain-free interval of minutes to days, after which there is progressive paralysis below the affected spinal level. Subarachnoid hematoma can be associated with meningitis symptoms, disturbances of consciousness, and epileptic seizures and is often misdiagnosed as cerebral hemorrhage based on these symptoms. Most patients are between 55 and 70 years old. Of all patients with spinal hemorrhage, 63.9% are men. The examination of first choice is magnetic resonance imaging. The treatment of choice is surgical decompression. Of the patients investigated in the present work, 39.6% experienced complete recovery. The less severe the preoperative symptoms are and the more quickly surgical decompression can be performed, the better are the chances for complete recovery. It is therefore essential to recognize the relatively typical clinical presentation of spinal hematoma in a timely manner to allow correct diagnostic and therapeutic measures to be taken to maximize the patient's chance of complete recovery.
601 citations
TL;DR: This paper surveys knowledge management (KM) development using a literature review and classification of articles from 1995 to 2002 with keyword index in order to explore how KM technologies and applications have developed in this period.
Abstract: This paper surveys knowledge management (KM) development using a literature review and classification of articles from 1995 to 2002 with keyword index in order to explore how KM technologies and applications have developed in this period. Based on the scope of 234 articles of knowledge management applications, this paper surveys and classifies KM technologies using the seven categories as: KM framework, knowledge-based systems, data mining, information and communication technology, artificial intelligence/expert systems, database technology, and modeling, together with their applications for different research and problem domains. Some discussion is presented, indicating future development for knowledge management technologies and applications as the followings: (1) KM technologies tend to develop towards expert orientation, and KM applications development is a problem-oriented domain. (2) Different social studies methodologies, such as statistical method, are suggested to implement in KM as another kind of technology. (3) Integration of qualitative and quantitative methods, and integration of KM technologies studies may broaden our horizon on this subject. (4) The ability to continually change and obtain new understanding is the power of KM technologies and will be the application of future works.
523 citations
TL;DR: In this article, a need statement is visualised based on a holistic concept of food production for the vegetable industry, recording occurrence, quantities and utilisation of the residual products, and a literature survey, covering more than 160 articles from all over the world, plus their own investigations summarises the latest knowledge in the above-mentioned field and outline prospects for future economic treatment of vegetable co-products.
519 citations
01 Jul 2003
TL;DR: The authors survey supervisors' ratings, analyses of piece-rates and employer-employee datasets as well as other approaches used to estimate how individual productivity varies with age, finding that older individuals maintain a relatively high productivity level in work tasks where experience and verbal abilities matter more.
Abstract: This article surveys supervisors' ratings, analyses of piece-rates and employer-employee datasets as well as other approaches used to estimate how individual productivity varies with age. The causes of productivity variations over the life cycle are addressed with an emphasis on how cognitive abilities affect labour market performance. Earnings tend to increase until relative late in the working life, while most evidence suggests that individuals' job performance tends to increase in the first few years of one's entry into the labour market, before it stabilises and often decreases towards the end of one's career. Productivity reductions at older ages are particularly strong when problem solving, learning and speed are important, while older individuals maintain a relatively high productivity level in work tasks where experience and verbal abilities matter more.
510 citations
TL;DR: In this article, a review of work on solar distillation, its present status in the world today and its future perspective has been made, including water sources, water demand, availability of potable water and purification methods including the state of art and historical background.
442 citations
Book•
18 Aug 2003
TL;DR: In this paper, the authors introduce decision-making units (DMUs) and the concepts of Efficiency Measurement (EM) and Frontier Analysis (FSA) to evaluate the efficiency of DMUs.
Abstract: PART ONE: INTRODUCTION Decision-Making Units Basic Concepts of Efficiency Measurement Graphical Description - Frontier Analysis Strongly and Weakly Efficient DMUs Exercises PART TWO: MATHEMATICAL PROGRAMMING ASPECTS OF DEA Mathematical Formulation Exercises Dual DEA Models Multiplier and Envelopment DEA Programmes Input and Output Oriented Envelopment DEA Programs Relationships among Different DEA Formulations Exercises PART THREE: ECONOMIES OF SCALE Returns to Scale and DEA Variable Returns to Scales Multiplier DEA Programs Technical and Scale Efficiencies Estimation of the Most Productive Scale Size Investigating the Returns to Scale Properties of a DMU Exercises PART FOUR: MISCELLANEOUS DEA MODELS AND RECENT DEVELOPMENTS Multiplicative DEA Models Additive Models Time Series Analysis using DEA Some Extensions of DEA Exercises Other DEA Models and Extensions PART FIVE: COMPUTER-BASED SUPPORT FOR DEA Computational Features of DEA DEA Software Internet Support for DEA A Brief Description of DEA Software PART SIX: DEA BIBLIOGRAPHY AND APPLICATIONS Brief Literature Survey Selected DEA Applications PART SEVEN: SOME ADDITIONAL DISCUSSION ON DATA ENVELOPMENT ANALYSIS Some Considerations on the Application Procedure of DEA Strengths and Limitations
438 citations
TL;DR: The aim was to generate and prove the concept of “smart” plants to monitor plant phosphorus (P) status in Arabidopsis, and to allow precision management of P fertilization, thereby maintaining yields while reducing costs, conserving natural resources, and preventing pollution.
Abstract: Our aim was to generate and prove the concept of "smart" plants to monitor plant phosphorus (P) status in Arabidopsis. Smart plants can be genetically engineered by transformation with a construct containing the promoter of a gene up-regulated specifically by P starvation in an accessible tissue upstream of a marker gene such as beta-glucuronidase (GUS). First, using microarrays, we identified genes whose expression changed more than 2.5-fold in shoots of plants growing hydroponically when P, but not N or K, was withheld from the nutrient solution. The transient changes in gene expression occurring immediately (4 h) after P withdrawal were highly variable, and many nonspecific, shock-induced genes were up-regulated during this period. However, two common putative cis-regulatory elements (a PHO-like element and a TATA box-like element) were present significantly more often in the promoters of genes whose expression increased 4 h after the withdrawal of P compared with their general occurrence in the promoters of all genes represented on the microarray. Surprisingly, the expression of only four genes differed between shoots of P-starved and -replete plants 28 h after P was withdrawn. This lull in differential gene expression preceded the differential expression of a new group of 61 genes 100 h after withdrawing P. A literature survey indicated that the expression of many of these "late" genes responded specifically to P starvation. Shoots had reduced P after 100 h, but growth was unaffected. The expression of SQD1, a gene involved in the synthesis of sulfolipids, responded specifically to P starvation and was increased 100 h after withdrawing P. Leaves of Arabidopsis bearing a SQD1::GUS construct showed increased GUS activity after P withdrawal, which was detectable before P starvation limited growth. Hence, smart plants can monitor plant P status. Transferring this technology to crops would allow precision management of P fertilization, thereby maintaining yields while reducing costs, conserving natural resources, and preventing pollution.
01 Jun 2003
TL;DR: A survey of the academic literature on the impact of natural resources on an economy can be found in this article, where the authors assess how the literature explains the transmission mechanisms between resource revenues and economic damage, and what political reforms might be needed to carry out the necessary policies to avoid negative impacts.
Abstract: Common sense and economic theory suggest large revenues from natural resource projects should generate economic progress and development. Yet much evidence argues the opposite and that resource-rich countries suffer from ‘resource curse’. This paper provides a survey of the academic literature on the impact of natural resources on an economy. The topic has long attracted interest in the economics literature but more recently, interest has revived. The paper first considers the large body of empirical work examining the relationship between resource abundance, poor economic performance and poverty. While this evidence supports the view of a negative impact, it is not without criticism and some assert a few countries managed instead to receive a ‘blessing’. The paper assesses how the literature explains the transmission mechanisms between resource revenues and economic damage. Six areas are discussed: a long-term decline in terms of trade; revenue volatility; Dutch disease; crowding out effects; increasing the role of the state; and the socio-cultural and political impacts. Finally, various options from the literature to avoid negative impacts are analysed: not developing the mineral deposits; diversifying the economy away from dependence on oil, gas and mineral exports; sterilising the incoming revenue; the use of stabilisation and oil funds; and reconsidering investment policies. The paper finishes by assessing what political reforms might be needed to carry out the necessary policies to avoid negative impacts.
TL;DR: In this article, the authors report on exploratory research on the potential of shared learning between firms, where common interests and interdependence provide motivation for experience sharing and other forms of synergy in learning.
Abstract: As firms struggle to cope with an increasingly turbulent and uncertain economic environment there is widespread recognition of the importance of organisational learning. One option is to look at the potential of shared learning between firms, where common interests and interdependence provide motivation for experience sharing and other forms of synergy in learning. A particular version of inter-firm learning is the use of supply chains as a mechanism for upgrading and transferring “appropriate practice” and this article reports on exploratory research on this theme. It draws on a literature survey and a detailed study of six UK supply chains at various stages of implementing supply chain learning.
TL;DR: It is suggested that shifts in the dominance of different bacterial strains in the environment are probably responsible for the large variation in bacterial biomass C : P, as has been suggested for crustacean zooplankton.
Abstract: Summary 1. We examined the relative importance of resource composition (carbon : phosphorus molar ratios which varied between 9 and 933) and growth rate (0·5‐1·5 h - 1 ) to biomass carbon : nitrogen : phosphorus stoichiometry and nucleic acid content in Escherichia coli grown in chemostats, and in other heterotrophic prokaryotes using published literature. 2. Escherichia coli RNA content and the contribution of RNA-P to total cellular P increased with increasing growth rate at all supply C : P ratios. Growth rate had a much stronger effect on biomass C : P than did supply C : P, and increased RNA content resulted in low biomass C : P and N : P ratios. 3. However, we observed only twofold variations in biomass C : P and N : P ratios in the experiments, despite a difference of two orders of magnitude in C : P and N : P supply. The response of biomass C : P and N : P ratios to alteration of the supply C : P and N : P ratios revealed that E. coli was strongly homeostatic in its elemental composition. 4. This result, and a literature survey, suggest that each heterotrophic bacterial strain regulates its elemental composition homeostatically within a relatively narrow range of characteristic biomass C : P and N : P ratios. 5. Thus shifts in the dominance of different bacterial strains in the environment are probably responsible for the large variation in bacterial biomass C : P, as has been suggested for crustacean zooplankton. These findings indicate that bacteria are more like animals than plants in terms of biomass C : P and N : P homeostasis.
TL;DR: This paper explores theoretical issues in ergonomics related to semantics and emotional content of design to find answers to the following questions: how to design products triggering ‘happiness’ in one's mind; which product attributes help in the communication of positive emotions; and finally, how to evoke such emotions through a product.
Abstract: This paper explores theoretical issues in ergonomics related to semantics and the emotional content of design. The aim is to find answers to the following questions: how to design products triggering "happiness" in one's mind; which product attributes help in the communication of positive emotions; and finally, how to evoke such emotions through a product. In other words, this is an investigation of the "meaning" that could be designed into a product in order to "communicate" with the user at an emotional level. A literature survey of recent design trends, based on selected examples of product designs and semantic applications to design, including the results of recent design awards, was carried out in order to determine the common attributes of their design language. A review of Good Design Award winning products that are said to convey and/or evoke emotions in the users has been done in order to define good design criteria. These criteria have been discussed in relation to user emotional responses and a selection of these has been given as examples.
13 Jan 2003
TL;DR: This paper provides a detailed survey of past work on document structure analysis algorithms and summarize the limitations of past approaches.
Abstract: Document structure analysis can be regarded as a syntactic analysis problem. The order and containment relations among the physical or logical components of a document page can be described by an ordered tree structure and can be modeled by a tree grammar which describes the page at the component level in terms of regions or blocks. This paper provides a detailed survey of past work on document structure analysis algorithms and summarize the limitations of past approaches. In particular, we survey past work on document physical layout representations and algorithms, document logical structure representations and algorithms, and performance evaluation of document structure analysis algorithms. In the last section, we summarize this work and point out its limitations.
TL;DR: In this article, the formation of chemically bonded phosphate ceramics is discussed and it is shown that the dissolution is the controlling step and developed a general dissolution model of the kinetics of formation.
Abstract: This is the first of three papers in which the kinetics of formation of chemically bonded phosphate ceramics is discussed. A literature survey indicates that the formation of such ceramics is a three-step process. First, oxides dissolve in a phosphoric acid or an acid phosphate solution and metal ions are released into the solution. The aquoions formed from these cations then react with phosphate anions and form a gel of metal hydrophosphates. In the last step, the saturated gel crystallizes into a ceramic. In this paper, we have proposed that the dissolution is the controlling step and developed a general dissolution model of the kinetics of formation of these ceramics. As an example, the model is used to discuss the kinetics of formation of magnesium phosphate ceramics in detail. In the second and third papers, the model has been used to develop processes to form ceramics of alumina and iron oxides.
TL;DR: In this article, a thorough investigation on the performance of broadband direct irradiance prediction using solar radiation models is detailed, and two new models were specifically developed for this study to provide state-of-the-art modelling of the broadband transmittances associated with the most important extinction processes in the atmosphere.
TL;DR: Temperature-driven shifts in nutrient content of organisms are likely to resonate in diverse ecological patterns and processes, including latitudinal and altitudinal patterns of nutrient content, foraging decisions by organisms living in strong temperature gradients, and patterns of biodiversity.
Abstract: Summary 1. Temperature strongly affects virtually all biological rate processes, including many central to organismal fitness such as growth rate. A second factor related to growth rate is organismal chemical composition, especially C : N : P stoichiometry. This association arises because high rates of growth require disproportionate investment in N- and P-rich biosynthetic cellular structures. Here the extent to which these factors interact is examined ‐ does acclimation temperature systematically affect organismal chemical composition? 2. A literature survey indicates that cold-acclimated poikilotherms contain on average 30‐50% more nitrogen [N], phosphorus [P], protein and RNA than warm-exposed conspecifics. The primary exception was bacteria, which showed increases in RNA content but no change in protein content at cold temperatures. 3. Two processes ‐ changes in nutrient content (or concentration) and in organism size ‐ contribute to the overall result. Although qualitatively distinct, both kinds of change lead to increased total catalytic capacity in cold-exposed organisms. 4. Temperature-driven shifts in nutrient content of organisms are likely to resonate in diverse ecological patterns and processes, including latitudinal and altitudinal patterns of nutrient content, foraging decisions by organisms living in strong temperature gradients, and patterns of biodiversity.
TL;DR: In this paper, the authors provide a state-of-the-art summary of risk assessment in energy trading, including portfolio analysis and hedging instruments, and provide a comprehensive critical literature survey of what has been applied to date in the power markets.
Abstract: This paper provides a state-of-the-art summary of risk assessment in energy trading. Techniques from financial engineering are needed by electric energy companies to manage price risk. These tools are needed by suppliers, distributors, and traders in a competitive electric power marketplace. Tools that have been adapted to the specific environment of the electric power system include portfolio analysis and hedging instruments. This paper provides a comprehensive critical literature survey of what has been applied to date in the power markets and which areas continue to need additional research. One example market scenario is used throughout the paper to demonstrate the usefulness of the risk assessment methods.
TL;DR: This paper reviews and classifies literature on the use of discrete event simulation for manufacturing system design and operation problems and a classification of a subset of these publications and the research and applications that underlie these publications.
TL;DR: In this article, the authors expand the existing knowledge about the determinants of corruption and provide incremental information to help the policy makers fight against this cancerous social disease, and find that economic freedom, socio-political stability, tradition of law abidance and national cultures are the major variables that dictate the degree of corruption.
Abstract: The background literature survey points to the fact that the degree of corruption is a function of multiple factors of a society. Thus, it is imperative to take a more comprehensive and cross‐disciplinary approach to understand the complete picture of corruption. The research findings indicate economic freedom, socio‐political stability, tradition of law abidance and national cultures are the major variables that dictate the degree of corruption. This study expands the existing knowledge about the determinants of corruption and provides incremental information to help the policy makers fight against this cancerous social disease.
TL;DR: The framework presented in this paper was developed from an analysis of environmental management practices in a number of companies along with a thorough literature survey and how the most important parts of the framework were computerised using KBS techniques.
Abstract: This paper outlines the development of a knowledge-based system (KBS) which integrates environmental factors into the supplier selection process. The system employs both case-based reasoning (CBR) and decision support components including multi-attribute analysis (MAA). Traditionally, when evaluating supplier performance, companies have considered factors such as price, quality, flexibility etc. However, with environmental pressures increasing, many companies have begun to consider environmental issues and the measurement of their suppliers' environmental performance. The framework presented in this paper was developed from an analysis of environmental management practices in a number of companies along with a thorough literature survey. The paper then outlines how the most important parts of the framework were computerised using KBS techniques. An evaluation of the system implemented in a multinational company is presented along with proposals for future system enhancements.
TL;DR: The main purpose of the article is to conduct performance comparisons on optical switching technologies in terms of basic performance, network requirements, and system requirements based on a literature survey.
Abstract: Optical switching technologies are very crucial to future mobile broadband all-optical IP networks. Many different optical switching technologies are currently available or under development. The main purpose of the article is to conduct performance comparisons on optical switching technologies in terms of basic performance, network requirements, and system requirements based on a literature survey. The technologies include switching based on optical microelectromechanical systems (MEMS), thermal optical switching, electro-optic switching, and acousto-optic switching technologies. Each optical switching technology has unique performance characteristics specific to the utilized optical phenomena. It might be crucial to integrate some technologies together to achieve a better solution for optical switching. Optical switching is a very hot topic attracting much research effort. Optical MEMS-based switching technology might be one of the most promising approaches at present. Many new optical switching technologies might be created in the near future. Through the impact of nanotechnology, some innovative approaches to optical switching might emerge.
TL;DR: It is calculated that, when analysing bulk zooplankton, inclusion of the gut mass may introduce substantial errors of >3 per thousand, and it appears prudent to perform the simple procedure of gut clearance, especially for copepod species.
Abstract: A literature survey of zooplankton stable isotope studies revealed inconsistencies between authors concerning (a) fixation and (b) allowance for gut clearance of zooplankton prior to δ13C and δ15N determinations. To address whether commonly used preservation techniques induce changes in stable isotope values, fresh lake zooplankton (control) were compared with preserved (ethanol, methanol, formaldehyde, gluteraldehyde, frozen and shock frozen) material. Differences of up to 1.1‰ for carbon and 1.5‰ for nitrogen isotopic signatures were found. Even freezing, the most frequently used method identified from the literature, caused significant changes compared with the control. We advocate the use of fresh material prepared immediately whenever possible, or complementary testing of the preservative method to be used. Larger organisms are routinely eviscerated, or specific tissues are dissected, and analysed for stable isotopes to reduce errors introduced via the gut contents. Yet zooplankton gut clearance is rarely performed: the gut content assumed to be negligible relative to organism mass. Experimental determinations of relative gut mass, from both original and compiled data, range from 1–26% for different zooplankton species. Using reported isotopic values of basal resources from natural systems, we calculated that, when analysing bulk zooplankton, inclusion of the gut mass may introduce substantial errors of >3‰. Thus it appears prudent to perform the simple procedure of gut clearance, especially for copepod species.
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TL;DR: In this article, the causes of productivity variations over the life cycle are addressed with an emphasis on how cognitive abilities affect labor market performance, finding that individual job performance decreases from around 50 years of age, which contrasts almost life-long increases in wages.
Abstract: This article surveys supervisors’ ratings, work-sample tests, analyzes of employer-employee datasets and other approaches used to estimate how individual productivity varies by age. The causes of productivity variations over the life cycle are addressed with an emphasis on how cognitive abilities affect labor market performance. Individual job performance is found to decrease from around 50 years of age, which contrasts almost life-long increases in wages. Productivity reductions at older ages are particularly strong for work tasks where problem solving, learning and speed are needed, while in jobs where experience and verbal abilities are important, older individuals’ maintain a relatively high productivity level.
TL;DR: The objective of this study was to compare the work-rest schedules for VDT operators considering data entry and mental arithmetic tasks and found the 15/micro schedule resulted in the highest speed, accuracy, and performance for both of the tasks, compared with the 60/10 and 30/5 schedules.
Abstract: Consideration of the literature survey indicates that video display terminal (VDT) operators tend to have a high incidence of musculoskeletal problems, visual fatigue, and job stress. Although a number of ergonomic improvements in workstation design and work environment can help to reduce these problems, a proper work-rest schedule deserves consideration since it is easily applicable and inexpensive. The objective of this study was to compare the work-rest schedules for VDT operators considering data entry and mental arithmetic tasks. An experiment was conducted with 10 male college students as participants. The methodology included a discomfort questionnaire and performance measures. The independent variables were the work-rest schedule (60-minute work/10-minute rest, 30-minute work/5-minute rest, and 15-minute work/micro breaks) and the type of task (data entry and a mental arithmetic task). The results were analysed using multiple analysis of variance followed by separate analyses. The 15/micro schedule resulted in significantly lower discomfort in the neck, lower back, and chest than the other schedules for data entry task. The 30/5 schedule followed by 15/micro schedule resulted in the lowest eyestrain and blurred vision. Discomfort in the elbow and arm was the lowest with the 15/micro schedule for the mental arithmetic task. The 15/micro schedule resulted in the highest speed, accuracy, and performance for both of the tasks, compared with the 60/10 and 30/5 schedules. The data entry task resulted in significantly increased speed, accuracy, and performance, and lower shoulder and chest discomfort than the mental arithmetic task.
TL;DR: This review reports the recent advances made on the therapeutical potential of aurones in different biological areas and discusses their synthesis, structure-activity relationships, and the importance of the substitution pattern.
Abstract: Aurones [2-benzylidenebenzofuran-3(2H)-ones] are the secondary metabolites natural compounds belong to the flavonoids family, and structurally are the isomers of flavones, widely present in fruits and flowers where they play significant role in the pigmentation of the part of plant in which they occur. Literature survey clearly indicates that flavones, chalcones, flavonols and isoflavones have been studied largely for their therapeutical potential. Somehow, aurones still are less studied and it is only recently that these compounds have begun to be investigated. In this review, we report the recent advances made on the therapeutical potential of aurones in different biological areas. Their synthesis, structure-activity relationships, the importance of the substitution pattern will also be discussed. Finally, some aspects regarding the possible development of aurones will be highlighted briefly.
TL;DR: The objective was to determine differences between industries which may provide information for benchmarking purposes and the results show significant differences in the design of Web sites across these different industry groups.
Abstract: For corporations engaged in e‐commerce, the Web serves as their primary interface with customers. Consequently, quality Web site design is a critical success factor for corporations with an e‐commerce strategy. However, no comprehensive and coherent set of evaluation criteria exists that corporations and researchers can use to examine Web sites. This paper fills this gap by proposing Web site evaluation criteria and applying these criteria to different industry groups within Korea. Based on the literature survey, six categories of Web site evaluation criteria are defined: business function; corporation credibility; contents reliability; Web site attractiveness; systematic structure; and navigation. Using these criteria, Web sites in 12 industries were evaluated to determine if there are differences in Web site design between industries. The objective was to determine differences between industries which may provide information for benchmarking purposes. The results show significant differences in the design of Web sites across these different industry groups.
TL;DR: In this paper, the authors derived the lens-redshift probability distribution, allowing for mass and number density evolution of the lensing galaxies, and applied this test to a much enlarged sample of lens systems.
Abstract: The redshifts of lens galaxies in known gravitational lens systems probe the volume distribution of the lensing mass. Following earlier work by Kochanek, we rederive the lens-redshift probability distribution, allowing for mass and number density evolution of the lensing galaxies, and apply this test to a much enlarged sample of lens systems. From a literature survey of all known lenses, we have selected an unbiased sample of 15 lenses with complete redshift information. For a flat universe and no lens evolution, we can only put an upper limit on the cosmological constant of Ω Λ 175 km s - 1 for elliptical galaxies is required (95 per cent CL).