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961.
962.
F. M. Reza 《Journal of The Franklin Institute》1985,320(6)
The normal family of linear (time-variant) n-ports is introduced as the most natural extension of ordinary scalar driving-point immittance behaviour. The normality induces a certain symmetry and simplicity which merits due emphasis in future n-port research investigations. As an application of the concept of normality the overdamped-underdamped criterion is extended to n-ports. Also, an interesting problem of maximal power transfer is solved and the absolute energy invariant index calculated. This paper invites attention to the development of circuit synthesis procedures based on the algebraic structure of the normal family. 相似文献
963.
Andrea L. Kavanaugh Debbie Denise Reese John M. Carroll Mary Beth Rosson 《The Information Society》2005,21(2):119-131
Communities with high levels of social capital are likely to have a higher quality of life than communities with low social capital. This is due to the greater ability of such communities to organize and mobilize effectively for collective action because they have high levels of social trust, dense social networks, and well-established norms of mutuality (the major features of social capital). Communities with “bridging” social capital (weak ties across groups) as well as “bonding” social capital (strong ties within groups) are the most effective in organizing for collective action. People who belong to multiple groups act as bridging ties. When people with bridging ties use communication media, such as the Internet, they enhance their capability to educate community members and to organize, as needed, for collective action. This article summarizes evidence from stratified household survey data in Blacksburg, VA, showing that people with weak (bridging) ties across groups have higher levels of community involvement, civic interest, and collective efficacy than people without bridging ties among groups. Moreover, heavy Internet users with bridging ties have higher social engagement, use the Internet for social purposes, and have been attending more local meetings and events since going online than heavy Internet users with no bridging ties. These findings may suggest that the Internet—in the hands of bridging individuals-is a tool for enhancing social relations and information exchange, and for increasing face-to-face interaction, all of which help to build both bonding and bridging social capital in communities. 相似文献
964.
A. Bhise P. V. Krishnan R. Aggarwal M. Gaiha J. Bhattacharjee 《Indian journal of clinical biochemistry : IJCB》2005,20(2):4-9
The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was
detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6
weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin
levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and
19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter.
After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and
group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively),
serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein
increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6
fatty acid may be used as an adjunctive measure in the management of essential hypertension. 相似文献
965.
Gamma Glutamyl Transferase (γ-GT) is a microsomal enzyme. Its activity in serum is assayed in alcoholics with liver abscess
and alcoholics without liver abscess after screening by ultrasonography. The enzyme activity in serum is increased by 334%
in the patients with liver abscess compared to normal control subjects (p<0.0001), and 172% when compared to patients with
chronic alcoholism without liver abscess (p<0.0001). The enzyme activity was increased by 59.3% in the serum of patients without
liver abscess compared to the normal control subjects (p<0.001). Measurement of γ-GT in serum appears to be a sensitive index
in the diagnosis of alcoholics with liver abscess. 相似文献
966.
R. Nalini C. R. Wilma Delphine Silvia Purnima M. Makhija Sheila Uthappa 《Indian journal of clinical biochemistry : IJCB》2005,20(1):165-168
Prognostic factors influence the modality and course of therapy in breast cancer. These include both histopathological and
biochemical variables. This study was aimed to find out if any correlation exists between the biochemical tumor marker-serum
CA 15.3, and the lymph node staging of Nottingham’s Prognostic Index (NPI). It was observed that serum CA 15.3 showed a statistically
significant correlation with lymph node staging of NPI. Therefore it is concluded that CA 15.3 can be utilized as a useful
prognostic marker, particularly in cases where histopathological variables such as tumor size and grade have been altered
by pre-operative chemotherapy. 相似文献
967.
The purpose of this paper is to examine whether the technical universities have been more successful in facilitating the spillover and commercialization of knowledge. We compare the impact of technical and general universities on the performance of knowledge-based firms. Based on a unique data set consisting of publicly held high technology firms, the empirical evidence suggests that, in fact, firm performance is not influenced by the type of university. Technical universities do not have a differential impact on firm performance from more general universities. 相似文献
968.
The increasing number of interactions between Taiwan and the Mainland may bring in both opportunities and competitions among the companies in the region. Companies are forced to continuously change and develop to advance and to sustain in the competitive environment. It also holds true for the companies in the even more competitive high-tech industries. It is therefore of a value to study what challenges the high-tech firms are facing, how these challenges impact on their performance and how these firms are dealing with issues. Among the multiple challenges, supply chain operation has been a critical issue concerning the high-tech manufacturers.The purpose of this study is to investigate the relationships between the various supply chain operation determinants (relationships with business partners, internal operation) and the impacts of relationships with supply chain partners on the internal operation and the collective efficacy relating to the scheduling issues in high-tech manufacturing firms in Taiwan. A research framework linking internal operation and relationships with supply chain partners (supplier and customer) and individuals (perceived collective efficacy) is applied. 相似文献
969.
In this study, we explore the coordination performance of the geographically distributed software development teams by exploring OSS (Open Source Software) development dataset available through SourceForge.com. OSS team structures have traditionally been geographically dispersed and therefore, the coordination of post release activities such as testing efforts have been carried out by means of communication via electronic forms, such as email or message boards and forums. In our current communication-enriched environment, best practices for coordination are adopted by all software projects yet some still fail to achieve their target performance. Does team structure have any bearing on the performance outcome of the project? How does the communication between teams and their external parties affect ultimate success or failure of projects? We seek to answer above questions by applying existing theories and analytical methods from social networks for exploring the coordination performance of defect management activities found in OSS projects. We propose social networks based theoretical model for exploring distributed coordination structure and apply that for the case of OSS defect management process for exploring the structural properties, which induce the greatest coordination performance. The outcome of our suggest that there is correlation between certain network measures such as density, centrality and betweenness and coordination performance measures of defect management systems such as quality and timeliness. 相似文献
970.
Elsie L. Echeverri-Carroll Michael D. Oden David V. Gibson Evan A. Johnston 《Research Policy》2018,47(1):209-217
There has been considerable media coverage highlighting the lack of gender diversity in Silicon Valley, stressing the relatively low participation of women in the high-tech economy. Austin offers a unique case for testing whether similar gender issues characterized other high-tech regions because the city has historically benefited from the expansion of Silicon Valley’s large high-tech firms since the 1980s. The gender-biased business practices identified in Silicon Valley firms may have been transferred to their branch plants in Austin. Our analysis shows women’s losses in middle-skill occupation employment shares were concentrated in the low-tech industry and were partially offset by job share gains in high-skill occupations in the same sector between 1980 and 2015. Men’s losses in middle-skill occupation job share were also mainly concentrated in the low-tech sector but were partially offset by employment share gains in high-skill occupations only in the high-tech industry during this period. Women made large gains in relative real median wages only in high-skill occupations in the high-tech industry while their relative real median wages in other skill occupations and in the low-tech industry stagnated around zero during this period. Men’s gains in relative median wages were also concentrated only in the high-tech industry but were less than half of women’s and were negative (between ?10 and ?21 percent) in other occupations in the high-tech industry and across all occupations in the low-tech industry. As noted in previous studies, the impact of job polarization is not well understood across sectors and gender. This study finds the high-tech industry in Austin has had unintended consequences in terms of job polarization across gender, providing relatively fewer job opportunities in high-skill occupations to women than men but offering much higher gains in relative real median wages to women than men. Males also found relatively more job opportunities in high-skill occupations in the high-tech industry than women but experienced only half of women’s gains in relative median wages in this industry between 1980 and 2015. 相似文献