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摘要： Legislators and industry leaders claim that patent strength in the United States has declined, causing firms to innovate in foreign countries. Because, however, patent law is bound by strict territorial limitations, one cannot strengthen patent protection by innovating abroad; as a result, scholarship has largely dismissed the theory that foreign patents have any effect on where firms invent. In essence, then, there is a debate pitting industry leaders against scholarship about whether firms can use offshore innovation to secure stronger patent rights, influencing the rate of innovation. To resolve this puzzle, we offer a novel theory of patent rights--which we empirically test--to dispel the positions taken by both scholarship and industry leaders. Given that technology is generally developed in one country, the innovation process exposes the typical inventor to infringement claims only in that jurisdiction. In turn, we demonstrate that inventors have powerful, counterintuitive incentives to develop technology where patent rights are weaker and enforcement is cheaper. Specifically, it typically costs more to defend a patent infringement claim in the United States than to lose one in another country (the cost to litigate a patent in the United States averages about $3.5 million and royalty awards have surpassed $2.5 billion). Our findings suggest that industry advocates and patent scholars overestimate how much innovation strong patent protection generates while underestimating the deterrent effect of these high costs of patent enforcement. This empirical research contributes to the theoretical understanding of patent rights by shedding new light on this important, yet largely dismissed, dimension of where innovation takes place. We received invaluable support from international research organizations and patent attorneys working for top-tier law firms. Notably, the Global IP Project, a multinational research group spearheaded by Finnegan, Henderson, Farabow, Garret

关键词： Computer science   Materials science   Pharmaceutical chemistry   Morphological operations   Image processing   Biomaterials   Microstructural analysis   Medical information systems   Data analysis   Data visualization   Computational materials science   Materials characterization   Materials structure   Microstructure   BONE-GRAFT   IMAGE   SEGMENTATION   BIOMATERIALS  

摘要： Numerous clinical studies have demonstrated the influence of the size, number and shape of pores into calcium phosphate ceramics on the process of bone regeneration. The main objective of this study is to determine the microstructure, the morphological characteristics and classes of pores of the prepared hydroxyapatite bioceramic using an adaptive method based on the mathematical morphological operations. The study was carried out using X-ray microtomography and Scanning Electron Microscopy images. The conventional method of openings alone presents limitation of calculation and not sufficient to achieve our objective. The proposed method allowed us to extract local characteristics and calculate precisely the morphological parameters while preserving the original volume of pores. The number and classes of pores with their size, surface of contact of the component and the number of connected pores to each pore were calculated. The method is subjectively and quantitatively evaluated using different computed phantoms and its efficiency is clearly demonstrated through the different reports and measurements generated. The proposed method can have interesting applications in the characterization of porous materials used in the medical field or in other sectors.

摘要： The authors discusses the relative paucity of U.S. high school and college students who are interested in computer science (CS) as a field of study and the experience of teaching first-year college students CS. The article examines steps being taken in U.S. states such as California and Texas to promote interest in CS among students and implementing CS education.

关键词： Citation analysis   Author-related factors   Future research performance   Bibliometric analysis   Information science   Computer science   BIBLIOMETRIC INDICATORS   INFORMATION-SCIENCE   RESEARCH IMPACT   H-INDEX   COLLABORATION   NETWORKS   CITATION   PUBLICATIONS   PRODUCTIVITY   AUTHORSHIP  

摘要： This paper examines how early career-related factors can predict the future research performance of computer and information scientists. Although a few bibliometric studies have previously investigated multiple factors relating to early career scientists that significantly predict their future research performance, there have been limited studies on early career-related factors affecting scientists in the fields of information science and computer science. This study analyzes 4102 scientists whose publishing careers started in the same year. The criteria used to quantify future research performance of the target scientists included the number of publications and citation counts of publications in a 4-year citation window to indicate future research productivity and research impact, respectively. These criteria were regressed on 13 early career-related factors. The results showed that these factors accounted for about 27% and 23% of the future productivity of the target scientists in terms of journal articles and conference papers, respectively; these 13 factors were also responsible for 19% of the future impact of target scientists' journal articles and 19% of the future impact of their conference papers. The factor that most contributed to explaining the future research performance (i.e. publication numbers) and future research impact (i.e. citation counts of publications) was the number of publications (both journal articles and conference papers) produced by the target scientists in their early career years.

关键词： Social capital   Prosocial attitudes   Death penalty   Capital punishment   GOVERNMENT PERFORMANCE   PUNISHMENT   THREAT   TRUST  

摘要： The division of opinions among Americans over the use of the death penalty is owed to a myriad of factors. While a number of works have examined public opinion on the death penalty, the extant literature does not examine the role of social capital as a determinant of support for or opposition to the death penalty. Here, it is argued that social capital explains in part why some Americans oppose the death penalty while other Americans do not. This investigation contends that social capital makes people less likely to support government action to kill convicted murderers. This hypothesis is confirmed. Utilizing data taken from the 2008 American National Election Study, the results of the logistic regression analyses show that social capital is inversely related to support for the death penalty.

关键词： Chan-Chuang qigong   stroke   mental aspect   mind-body interactive exercise   physical aspect   quality of life   rehabilitation   HEART-RATE-VARIABILITY   TAI CHI   ISCHEMIC-STROKE   AUTONOMIC DYSFUNCTION   CANCER-PATIENTS   REHABILITATION   DEPRESSION   THERAPY   ANXIETY   INTERVENTION  

摘要： Background: Stroke, a medical condition that causes physical disability and mental health problems, impacts negatively on quality of life. Post-stroke rehabilitation is critical to restoring quality of life in these patients. Objectives: This study was designed to evaluate the effect of a mind-body interactive qigong intervention on the physical and mental aspects of quality of life, considering bio-physiological and mental covariates in subacute stroke inpatients. Methods: A randomized controlled trial with repeated measures design was used. A total of 68 participants were recruited from the medical and rehabilitation wards at a teaching hospital in northern Taiwan and then randomly assigned either to the Chan-Chuang qigong group, which received standard care plus a 10-day mind-body interactive exercise program, or to the control group, which received standard care only. Data were collected using the National Institutes of Health Stroke Scale, Hospital Anxiety and Depression Scale, Short Form-12, stroke-related neurologic deficit, muscular strength, heart rate variability and fatigue at three time points: pre-intervention, halfway through the intervention (day 5) and on the final day of the intervention (day 10). Results: The results of the mixed-effect model analysis showed that the qigong group had a significantly higher quality of life score at day 10 (p<0.05) than the control group. Among the covariates, neurologic deficit (p=0.04), muscle strength (p=0.04), low frequency to high frequency ratio (p=0.02) and anxiety (p=0.04) were significantly associated with changes in quality of life. Conversely, heart rate, heart rate variability (standard deviation of normal-to-normal intervals, low frequency and high frequency), fatigue and depression were not significantly associated with change in quality of life (p >0.05). Conclusions: This study supports the potential benefits of a 10-day mind-body interactive exercise (Chan-Chuang qigong) program for subacute stroke i

关键词： Semiotics   Grounding   Cognitive systems   Computer science   Robot sensing systems   Artificial intelligence (AI)   developmental robotics   language acquisition   symbol emergence   symbol grounding   GROUNDING TRANSFER   YOUNG-CHILDREN   LANGUAGE   ACQUISITION   COMPREHENSION   ORGANIZATION   RECOGNITION   EVOLUTION   ROBOTICS   INFANTS  

摘要： Humans use signs, e.g., sentences in a spoken language, for communication and thought. Hence, symbol systems like language are crucial for our communication with other agents and adaptation to our real-world environment. The symbol systems we use in our human society adaptively and dynamically change over time. In the context of artificial intelligence (AI) and cognitive systems, the symbol grounding problem has been regarded as one of the central problems related to symbols. However, the symbol grounding problem was originally posed to connect symbolic AI and sensorimotor information and did not consider many interdisciplinary phenomena in human communication and dynamic symbol systems in our society, which semiotics considered. In this paper, we focus on the symbol emergence problem, addressing not only cognitive dynamics but also the dynamics of symbol systems in society, rather than the symbol grounding problem. We first introduce the notion of a symbol in semiotics from the humanities, to leave the very narrow idea of symbols in symbolic AI. Furthermore, over the years, it became more and more clear that symbol emergence has to be regarded as a multifaceted problem. Therefore, second, we review the history of the symbol emergence problem in different fields, including both biological and artificial systems, showing their mutual relations. We summarize the discussion and provide an integrative viewpoint and comprehensive overview of symbol emergence in cognitive systems. Additionally, we describe the challenges facing the creation of cognitive systems that can be part of symbol emergence systems.

关键词： Indexes   Search engines   Heuristic algorithms   Approximation algorithms   Google   Companies   Computer science   Index shard   search engine   replication   resource usage   heuristic algorithms  

摘要： With the rapid growth of the Web scale, large scale search engines have to set up a huge number of machines to place the index files of the Web contents. The index files are normally divided into smaller index shards which are often replicated so that queries can be processed in parallel. We observe from real systems that the index shard replication strategy could have a significant impact on the resource usage. In this paper, we investigate the index shard replication problem with the goal of minimizing the resource usage in search engine datacenters. We consider both the offline version and online version of the problem, and formulate the problems as non-linear integer programming problems. We propose several heuristic algorithms to approximate the optimal solution. The proposed algorithms are evaluated by extensive experiments using both synthetic data and real data from commercial search engines. The results demonstrate the effectiveness of the proposed algorithms. Our work also yields many insights about the impact of different input properties on the performance of each algorithm. We believe that this paper will provide valuable guidance to the design of the index shard replication strategy in practice.

关键词： Trematodes   Himasthla sp.   Parasites   Ocean acidification and warming   Cercariae   Marine ecology   Survival   ULTRAVIOLET-RADIATION   TEMPERATURE   CERCARIAE   SURVIVAL   TRANSMISSION   EMERGENCE   INFECTIVITY   METABOLISM   THERMODYNAMICS   INCREASES  

摘要： Human activities have caused an increase in atmospheric CO2 over the last 250 years, leading to unprecedented rates of change in seawater pH and temperature. These global scale processes are now commonly referred to as ocean acidification and warming, and have the potential to substantially alter the physiological performance of many marine organisms. It is vital that the effects of ocean acidification and warming on marine organisms are explored so that we can predict how marine communities may change in future. In particular, the effect of ocean acidification and warming on host-parasite dynamics is poorly understood, despite the ecological importance of these relationships. Here, we explore the response of one himasthlid trematode, Himasthla sp., an abundant and broadly distributed species of marine parasite, to combinations of elevated temperature and pCO(2) that represent physiological extremes, pre-industrial conditions, and end of century predictions. Specifically, we quantified the life span of the free-living cercallal stage under elevated temperature and pCO(2), focussing our research on functional life span (the time cercariae spend actively swimming) and absolute life span (the period before death). We found that the effects of temperature and pCO(2) were complex and interactive. Overall, increased temperature negatively affected functional and absolute life span, e.g. across all pCO(2) treatments the average time to 50% cessation of active swimming was approximately 8 h at 5 degrees C, 6 h at 15 degrees C, 4 h at 25 degrees C, and 2 h at 40 degrees C. The effect of pCO(2), which significantly affected absolute life span, was highly variable across temperature treatments. These results strongly suggest that ocean acidification and warming may alter the transmission success of trematode cercariae, and potentially reduce the input of cercariae to marine zooplankton. Either outcome could substantially alter the community structure of coastal marine systems.

关键词： Time-varying systems   Linear systems   Control theory   Physics   Sociology   Computer science   Discrete linear time-varying system   Lyapunov exponent   upper Bohl exponent   STABILITY  

摘要： In this paper, we present necessary and sufficient conditions for two given functions to be the Lyapunov and the upper Bohl exponent of a certain discrete linear system with diagonal coefficients. The obtained conditions have a form of easily verifiable algebraic conditions.