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131.
“云南契丹后裔”又称本人(或本族),是北方古老游牧民族——契丹族的遗裔;这一族群在内蒙古民族研究所和云南民族研究所等多方机构的协作下于1992年被发现,一时学界震惊;自此,云南契丹后裔便成为学界关注的焦点,众多学科研究闻风而来,各项研究成果颇丰,而针对这些研究成果分门别类地进行归纳和总结,则有助于对云南契丹后裔这一族群的研究工作更好地深入开展. 相似文献
132.
对海峡西岸经济区民营经济较发达的福州、厦门、泉州3个城市28家大中型民营企业职工体育基本特征进行分析。提出既有时代特征又具地域特色的"层级型"、"福利型"、"自治型"、"共建型"、"圈子型"、"营销型"、"带动型"民营企业职工体育发展模式,为民营企业职工体育和谐发展提供参考。 相似文献
133.
Many services can be self-provided. An individual user or a user firm can, for example, choose to do its own accounting - choose to self-provide that service - instead of hiring an accounting firm to provide it. Since users can ‘serve themselves’ in many cases, it is reasonable to suspect that they can also innovate with respect to the services they self-provide - possibly without the assistance of service providers.In this paper, we conduct the first quantitative exploration of the importance of services innovation by users, focusing on the field of commercial and retail banking services. We find that 55% of today's computerized commercial banking services were first developed and implemented by non-bank firms for their own use, and 44% of today's computerized retail banking services were first developed and implemented by individual service users rather than by commercial financial service providers. Manual precursors to these services - manual procedures that carried out functions similar to computerized services in our sample - were almost always developed by users as self-services.Our empirical findings differ significantly from prevalent producer-centered views of service development. We speculate that the patterns we have observed in banking with respect to the major role of users in service development will prove to be quite general. If so, this will be an important matter: on the order of 75% of GDP in advanced economies today is derived from services. We discuss the implications of our findings for research and practice in service development. 相似文献
134.
提出了802.11s无线Mesh网络中协作多样性感知的路由度量,并提出了适应无线Mesh网络特点的协作式路由协议(CDARP)与协作媒体访问控制协议(CMAC).通过构建协作虚拟节点、计算协作链路度量,CDARP-CMAC能够选择最合理的路径进行协作数据传输.实验结果表明,与最优路径的协作机制相比,CDARP-CMAC协议提高了网络有效吞吐量5%~13%;同时降低了数据包丢包率5%~10%. 相似文献
135.
We first present in this paper an analytical view of heuristic retrieval constraints which yields simple tests to determine
whether a retrieval function satisfies the constraints or not. We then review empirical findings on word frequency distributions
and the central role played by burstiness in this context. This leads us to propose a formal definition of burstiness which
can be used to characterize probability distributions with respect to this phenomenon. We then introduce the family of information-based
IR models which naturally captures heuristic retrieval constraints when the underlying probability distribution is bursty
and propose a new IR model within this family, based on the log-logistic distribution. The experiments we conduct on several
collections illustrate the good behavior of the log-logistic IR model: It significantly outperforms the Jelinek-Mercer and
Dirichlet prior language models on most collections we have used, with both short and long queries and for both the MAP and
the precision at 10 documents. It also compares favorably to BM25 and has similar performance to classical DFR models such
as InL2 and PL2. 相似文献
136.
Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body. 相似文献
137.
Allan J. Hicks Zoe L. Carwardine Mike J. Hallworth Eric S. Kilpatrick 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(1)
IntroductionIt is often quoted that 70% of clinical decisions are based on laboratory results, but the evidence to substantiate this claim is lacking. Since clinical guidelines aim to document best-practice decision making for specific disease conditions, inclusion of any laboratory test means that the best available evidence is recommending clinicians use it. Cardiovascular disease (CVD) is the world’s most common cause of mortality, so this study reviewed all CVD guidelines published by five national/international authorities to determine what proportion of them recommended laboratory testing.Materials and methodsFive leading CVD guidelines were examined, namely the European Society of Cardiology (ESC), the UK National Institute for Health and Clinical Excellence (NICE), the American College of Cardiology (ACC), the Australian Heart Foundation (AHF) and the Cardiac Society of Australia and New Zealand (CSANZ).ResultsA total of 101 guidelines were reviewed. Of the 33 individual ESC guidelines relating to CVD, 24/33 made a direct reference to the use of clinical laboratory tests in either diagnosis or follow-up treatment. The same applied to 15/20 of NICE guidelines, 24/32 from the ACC and 15/16 from the AHF/CSANZ. Renal function and blood count testing were the most recommended (39 and 26 times), with lipid, troponin and natriuretic peptide measurement advocated 25, 19 and 19 times respectively.ConclusionsThis study has shown that laboratory testing is advocated by between 73% and 94% of individual CVD guideline recommendations from five national/international authorities. This provides an index to assess the potential value of laboratory medicine to healthcare. 相似文献
138.
在我国高职英语教学中,阅读教学是非常基础,也是非常重要的一部分。改善高职英语阅读教学,有利于提升学生的核心素养。基于此,该文重点针对核心素养导向下的高职英语阅读教学方法进行了详细的分析。 相似文献
139.
Eric S. Zeemering 《Government Information Quarterly》2021,38(1):101539
The organization of city government into specialized departments allows cities to accomplish an array of service delivery tasks. Government reformers argue this fragmentation creates coordination challenges when problems spillover the lines of specialized agencies. Functional fragmentation also poses coordination challenges for government communication with the public through social media. The global SARS-CoV-2 pandemic and COVID-19 disease provide an opportunity to investigate the consequences of functional fragmentation in city government for social media communication about public health and pandemic response. A comparative case analysis of three cities using data from city agency Twitter accounts and key informant interviews demonstrates the consequences of fragmentation for internal coordination, as well as public outreach. The experiences of Atlanta, San Francisco, and Washington, DC in the early days of the pandemic provide pragmatic insights for city officials and illustrate the theoretical importance of giving attention to whole of government approaches to city social media communication. 相似文献
140.
Miriam L. Matteson Yue Ming David E. Silva 《Library & information science research》2021,43(2):101093
Library employees hold perceptions about the fairness of the outcomes, processes, and interpersonal treatment in their workplaces. When employees feel the workplace is fair they are more likely to feel commitment to the organization, perform in-role and extra-role tasks, and experience job satisfaction. When employees perceive injustice in the workplace, research points to negative outcomes such as withholding work or even sabotage. To understand the antecedents of organizational justice, researchers carried out a national survey of librarians to compare the predictive power of perceived organizational support, job autonomy, job feedback, and job stress. Results indicate that increasing librarians' perceptions of organizational support and their autonomy, and providing meaningful and timely job feedback can increase overall perceptions of justice. Managers can enhance a climate of justice in their workplaces by developing strategies that target organization support, autonomy, and feedback to reduce a sense of injustice between and among employees. 相似文献