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排序方式: 共有476条查询结果,搜索用时 20 毫秒
81.
Continuous monitoring systems generate continuous business intelligence by gathering text from a range of sources and typically storing that text information using snippets of text. Further, continuous monitoring systems derive information from those snippets, such as sentiment and new concepts emerging in the text, beyond the existing ontology and dictionaries. However, it is difficult for users to gather much additional information from large quantities of text snippets. As a result, this paper investigates introducing the notion of “knowledge graphs” into such systems and analyzes some of the potential applications and capabilities in business intelligence settings. As part of that analysis, this paper extends current-generation continuous monitoring systems to include knowledge graphs.  相似文献   
82.
研究利用Matching Pursuit(MP)方法实现的图像稀疏分解算法,针对其中关键难题,提出利用在低维空间的搜索实现高维空间的搜索的快速方法。算法的有效性为实验结果所证实。  相似文献   
83.
We present a formalized account of decision making as a multistep process that involves several classes of participating entities. The purpose of this article is to lay the foundations for a conceptual framework in which decision support systems can be placed. A series of increasingly formal representations of the decision problem are developed, from a mental model conceived by the decision maker to a knowledge base that may be used in a decision support system. The reformulations of the decision problem lead us to contemplate different forms of support: for mental models, for formal models (this includes supporting measurement and representation), for solution, and for communication.  相似文献   
84.
巨灾债券与巨灾保险风险分散   总被引:4,自引:0,他引:4  
巨灾债券,作为一种债权合同,相对于巨灾再保险而言,虽然是一个两极端产品,但在分散风险方面具有其不可比拟的优势。在大额损失时,巨灾债券是巨灾再保险的一种很好的替代产品。另外,巨灾风险债券的发行对巨灾再保险免赔额具有积极影响。  相似文献   
85.
Axiomatic approach to approximate solutions in multiobjective optimization   总被引:1,自引:0,他引:1  
An axiomatic approach is introduced in order to study the approximate solution map of a vector optimization problem in the image space. We investigate the possibility to formulate an appropriate notion of approximate solutions that is compatible with von Neumann–Morgenstern utility theory. An impossibility result is proved in the sense that, whenever all of the axioms are satisfied, either the set of the approximate solutions is a subset of the exact solutions of the problem, or it coincides with the whole admissible set. Moreover, the geometry of the approximate solution map is studied in some special cases.   相似文献   
86.
Background and aim: The impact of nocturia (getting up at night to void) on health-related quality-of-life (HRQoL) is often under-estimated. This study investigated the relative burden in terms of HRQoL and utilities of nocturia in a real-world setting.

Methods: Patient data were collected from two surveys: a nocturia-specific, cross-sectional survey of physicians and their patients (DSP), and a general UK population health survey (HSFE). Utilities (EQ-5D-5L), productivity (Work Productivity and Activity Index), and the impact of nocturia symptoms (Nocturia Impact Diary and Overactive Bladder Questionnaires) were assessed against the number of voids. A robust linear regression model with propensity score weights was used to control for confounding factors in estimating utilities.

Results: Physician-recorded data were available from 8,738 patients across the US, Germany, Spain, France, and the UK; of these, 5,335 (61%) included patient-reported outcomes. In total, 6,302 controls were drawn from the two surveys and compared to 1,104 nocturia patients. Deterioration of HRQoL was associated with increasing number of night-time voids (p?p?p?Limitations: The cause of nocturia is multifactorial and the mostly elderly patients may have several concomitant diseases. The authors tried to adjust for the most common ones, but there may be diseases or unknown relationships not included.

Conclusions: Nocturia negatively affected HRQoL and patient utility. A clear effect is seen already at two voids per night. Every effort should, therefore, be made to reduce nocturia below the bother threshold of two voids per night.  相似文献   
87.
Members are the most important stakeholders in membership organizations; their involvement can enhance organizational effectiveness, accountability, and legitimacy. Previous literature, however, has primarily explored these concepts by focusing on staff involvement or client participation. This paper examines the determinants of members’ involvement in membership organizations using cross-sectional data from Lebanese membership organizations. Primary findings suggest that members’ involvement is affected by the gender of leadership, internal fiscal capacity, and the size of the organization; small organizations, those led by women, and organizations with greater internal fiscal capacity are more likely to have greater participation by members.  相似文献   
88.
Tourism research has recently been informed by non-representational theories to highlight the socio-material, embodied and heterogeneous composition of tourist experiences. These advances have contributed to further reflexivity and called for novel ways to animate representations. On this background, this article develops the notion ‘distorted representation’ to illustrate that blurred and obscure photos can in fact be intelligible and sensible in understanding tourism. Through an exploration of the overwhelmed and unintended practices of visual fieldwork, distorted representation illustrates how photographic materialities, performativities and sensations contribute to new tourism knowledges. While highlighting the potential of distorted representation, the article posits a cautionary note in regards to the influential role of academic journals in determining the qualities of visual data. The article exemplifies distorted representation through three impressionistic tales derived from ethnographic research on the European rail travel phenomenon: interrail.  相似文献   
89.
The famous Afriat’s theorem from the theory of revealed preferences establishes necessary and sufficient conditions for the existence of utility function for a given set of choices and prices. The result on the existence of a homogeneous utility function can be considered as a particular fact of the Monge–Kantorovich mass transportation theory. In this paper we explain this viewpoint and discuss some related questions.  相似文献   
90.
《Journal of medical economics》2013,16(11):1307-1316
Abstract

Objective:

The objective of the study was to conduct a systematic review of utility weight estimates relevant to economic models for wet age-related macular degeneration (wAMD).

Methods:

A systematic literature search of PubMed, Embase, the Cochrane Library, and EconLit was performed (January 1995–December 2010) and then updated (October 2010–May 2012; February 2012–July 2013) identifying articles reporting utilities in patients with wAMD and visual impairment. Extracted studies were also assessed for compliance with the NICE reference case.

Results:

Of 2415 articles identified from the searches, 212 articles were reviewed in full, and 17 selected for data extraction. Most studies used time trade-off (TTO) techniques to estimate utilities; other methods included standard gamble, EuroQoL Health Questionnaire 5 Dimensions (EQ-5D); Short-Form 6D Health Status Questionnaire (SF-6D); and Health Utilities Index Mark III (HUI3). Correlation between utility estimates and visual acuity (VA) differed between the instruments. Time trade-off methods were more sensitive to VA changes than standard gamble methods. HUI3 estimates were most highly correlated with VA changes, followed by TTO; no trend was observed between VA and EQ-5D or SF-6D utility weights. Six of the 17 studies complied with the NICE reference case.

Conclusions:

Several instruments have been used to elicit utilities from patients with wAMD. Because TTO methods were more sensitive to VA changes than standard gamble and HUI3 estimates were most highly correlated with VA changes, TTO and HUI3 may be suitable methods for economic evaluations in these patients. The EQ-5D and SF-6D were poor indicators of the impact of VA on HRQL.  相似文献   
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