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11.
The Franklin Institute, Philadelphia, Pennsylvania awarded the 2001 Benjamin Franklin Medal in Life Science to Judah Folkman for his founding of the field of angiogenesis research and demonstration that angiogenesis is a necessary factor in the conversion of abnormal cells to malignant tumors.  相似文献   
12.
This study attempts to answer two questions. First, can a single cultural event impact the stock prices of a wide range of companies and sectors? Second, was the positive stock market response in the information technology (IT) sector as well as performing arts sector significant? To answer these questions, we examine whether a hit pop single, “Gangnam Style” by Park Jae-Sang in 2012, affected related sectors of the Korean stock market and whether market reactions went beyond the stock price of the singer’s agency to affect those of other firms. We use an event study approach. The results show two notable empirical findings. First, although the findings indicating abnormal returns and cumulative abnormal returns appear mixed, the overall results imply that the unprecedented worldwide hit single by the South Korean singer positively affected the Recreation & Culture and Digital Content sectors. In other words, the market interpreted the event as good news, with shareholders expecting positive effects on the related sectors. Second, a positive stock market response was observed in the IT sector as well.  相似文献   
13.
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics.  相似文献   
14.
In recent years, there has been rapid growth in the volume of research output on the topic of e-government. To understand this research better, we used content analysis of eighty-four papers in e-government-specific research outlets (two journals and one conference series). Our analytical focus took in five main aspects: perspectives on the impacts of e-government, research philosophy, use of theory, methodology and method, and practical recommendations. Normative evaluation identified some positive features, such as recognition of contextual factors beyond technology, and a diversity of referent domains and ideas. Alongside this, though, research draws mainly from a weak or confused positivism and is dominated by over-optimistic, a-theoretical work that has done little to accumulate either knowledge or practical guidance for e-government. Worse, there is a lack of clarity and lack of rigor about research methods alongside poor treatment of generalization. We suggest ways of strengthening e-government research but also draw out some deeper issues, such as the role of research philosophy and theory, and the institutional factors – particularly pressures of competition and time – that may constrain development of e-government as a research field.  相似文献   
15.
The implementation of e-government is a burgeoning phenomenon across the globe. It improves and enhances the infrastructures and services provided to the citizens. However, a review of the IS literature reveals that research on the implementation of e-government is rather limited, which could be due to the general misconception of the public sectors as rigid and risk-averse establishments. The shortage of studies on e-government’s implementation presents a knowledge gap that needs to be plugged. This gap is significantly amplified by the increasing number of e-government initiatives being implemented by governments in recent years. This paper describes and analyzes South Korea’s Supreme Court Registry Office, which has implemented e-government. The case study discusses practical implications and suggests future research areas. Findings of the study include the alignment of technology and business processes, integration of resources into core business activities, integrating stakeholders’ trust and commitment, and better understanding of the role of organizational learning, which can enhance the adoption and institutionalization of e-government initiatives.  相似文献   
16.
The role and continued relevance of state telecommunications regulators have been challenged by the development of competition, the introduction of new technologies, and the increasing dominance of federal authority. An important role that state utility commissions can play in the current telecommunications environment is to provide consumer education and information about consumer protection, competition, and universal service. Commissions can use their Web sites as effective tools in educating and informing consumers. This study analyzes the consumer-related telecommunications information included on the Web sites of the commissions in the 50 states and the District of Columbia to determine whether, and how well, state commissions are using their Web sites to educate and inform.  相似文献   
17.
Mass transport in porous materials is universal in nature, and its worth attracts great attention in many engineering applications. Plant leaves, which work as natural hydraulic pumps for water uptake, have evolved to have the morphological structure for fast water transport to compensate large water loss by leaf transpiration. In this study, we tried to deduce the advantageous structural features of plant leaves for practical applications. Inspired by the tissue organization of the hydraulic pathways in plant leaves, analogous double-layered porous models were fabricated using agarose hydrogel. Solute transport through the hydrogel models with different thickness ratios of the two layers was experimentally observed. In addition, numerical simulation and theoretical analysis were carried out with varying porosity and thickness ratio to investigate the effect of structural factors on mass transport ability. A simple parametric study was also conducted to examine unveiled relations between structural factors. As a result, the porosity and thickness ratio of the two layers are found to govern the mass transport ability in double-layered porous materials. The hydrogel models with widely dispersed pores at a fixed porosity, i.e., close to a homogeneously porous structure, are mostly turned out to exhibit fast mass transport. The present results would provide a new framework for fundamental design of various porous structures for effective mass transport.  相似文献   
18.
In this study, we simulated deformation and surfactant distribution on the interface of a surfactant-covered droplet using optical tweezers as an external source. Two optical forces attracted a single droplet from the center to both sides. This resulted in an elliptical shape deformation. The droplet deformation was characterized as the change of the magnitudes of surface tension and optical force. In this process, a non-linear relationship among deformation, surface tension, and optical forces was observed. The change in the local surfactant concentration resulting from the application of optical forces was also analyzed and compared with the concentration of surfactants subjected to an extensional flow. Under the optical force influence, the surfactant molecules were concentrated at the droplet equator, which is totally opposite to the surfactants behavior under extensional flow, where the molecules were concentrated at the poles. Lastly, the quasi-equilibrium surfactant distribution was obtained by combining the effects of the optical forces with the extensional flow. All simulations were executed by the lattice Boltzmann method which is a powerful tool for solving micro-scale problems.  相似文献   
19.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2001 Benjamin Franklin Medal in Earth Science to Rob Van der Voo for his outstanding contributions to the field of paleomagnetism and his reconstruction of ancient continental positions that have lead to a better understanding of plate tectonic processes for the past billion years of Earth history.  相似文献   
20.
A transaction log analysis of the Nanyang Technological University (NTU) OPAC was conducted to identify query and search failure patterns with the goal of identifying areas of improvement for the system. One semester’s worth of OPAC transaction logs were obtained and from these, 641,991 queries were extracted and used for this work. Issues investigated included query length, frequency and type of search options and Boolean operators used as well as their relationships with search failure. Among other findings, results indicate that a majority of the queries were simple, with short query lengths and a low usage of Boolean operators. Failure analysis revealed that on average, users had an almost equal chance of obtaining no records or at least one record to a submitted query. We propose enhancements and suggest future areas of work to improve the users’ search experience with the NTU OPAC.  相似文献   
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