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201.
For a connected graph \(G = \left( V,E\right) \), a set \(S\subseteq E(G)\) is called a total edge-to-vertex monophonic set of a connected graph G if the subgraph induced by S has no isolated edges. The total edge-to-vertex monophonic number \(m_{tev}(G)\) of G is the minimum cardinality of its total edge-to-vertex monophonic set of G. The total edge-to-vertex monophonic number of certain classes of graphs is determined and some of its general properties are studied. Connected graphs of size \(q \ge 3 \) with total edge-to-vertex monophonic number q is characterized. It is shown that for positive integers \(r_{m},d_{m}\) and \(l\ge 4\) with \(r_{m}< d_{m} \le 2 r_{m}\), there exists a connected graph G with \(\textit{rad}_ {m} G = r_{m}\), \(\textit{diam}_ {m} G = d_{m}\) and \(m_{tev}(G) = l\) and also shown that for every integers a and b with \(2 \le a \le b\), there exists a connected graph G such that \( m_{ev}\left( G\right) = b\) and \(m_{tev}(G) = a + b\). A forcing subset for S of minimum cardinality is a minimum forcing subset of S. The forcing total edge-to-vertex monophonic number of S, denoted by \(f_{tev}(S)\) is the cardinality of a minimum forcing subset of S. The forcing total edge-to-vertex monophonic number of G, denoted by \(f_{tev}(G) = \textit{min}\{f_{tev}(S)\}\), where the minimum is taken over all total edge-to-vertex monophonic set S in G. The forcing total edge-to-vertex monophonic number of certain classes of graphs are determined and some of its general properties are studied. It is shown that for every integers a and b with \(0 \le a \le b\) and \(b \ge 2\), there exists a connected graph G such that \(f_{tev}(G) = a\) and \( m _{tev}(G) = b\), where \( f _{tev}(G)\) is the forcing total edge-to-vertex monophonic number of G.  相似文献   
202.
In this article, we examine birth cohort differences in parents’ provision of monetary help to adult children with particular focus on the extent to which cohort differences in family structure and the transition to adulthood influence these changes. Using data from the Health and Retirement Study from 1994 to 2010, we compare financial help to children of three respondent cohorts as the parents in these birth cohorts from ages 53–58 to 57–62. We find that transfers to children have increased among more recent cohorts. Two trends—declining family size and children’s delay in marriage—account for part of the increase across cohorts. However, other trends, such as the increase in the number of stepchildren and increasing child’s income level, tend to decrease the observed cohort trend.  相似文献   
203.
Over the past five years the Artificial Intelligence Center at SRI has been developing a new technology to address the problem of automated information management within real- world contexts. The result of this work is a body of techniques for automated reasoning from evidence that we call evidential reasoning. The techniques are based upon the mathematics of belief functions developed by Dempster and Shafer and have been successfully applied to a variety of problems including computer vision, multisensor integration, and intelligence analysis.

We have developed both a formal basis and a framework for implementating automated reasoning systems based upon these techniques. Both the formal and practical approach can be divided into four parts: (1) specifying a set of distinct propositional spaces, (2) specifying the interrelationships among these spaces, (3) representing bodies of evidence as belief distributions, and (4) establishing paths of the bodies for evidence to move through these spaces by means of evidential operations, eventually converging on spaces where the target questions can be answered. These steps specify a means for arguing from multiple bodies of evidence toward a particular (probabilistic) conclusion. Argument construction is the process by which such evidential analyses are constructed and is the analogue of constructing proof trees in a logical context.

This technology features the ability to reason from uncertain, incomplete, and occasionally inaccurate information based upon seven evidential operations: fusion, discounting, translation, projection, summarization, interpretation, and gisting. These operation are theoretically sound but have intuitive appeal as well.

In implementing this formal approach, we have found that evidential arguments can be represented as graphs. To support the construction, modification, and interrogation of evidential arguments, we have developed Gister. Gister provides an interactive, menu-driven, graphical interface that allows these graphical structures to be easily manipulated.

Our goal is to provide effective automated aids to domain experts for argument construction. Gister represents our first attempt at such an aid.  相似文献   

204.
埃德加·莫兰的复杂性思想主体包括三大理论:建立在有序性与无序性统一基础上的自组织理论、建立在整体与部分相互决定基础上的多样性理论以及建立在主客体相整合基础上的自我反思理论.莫兰的复杂性思想与"简单范式"针锋相对,自然构成了时以"简单范式"为基础的人类学的批判.本文以人类学研究的某些方面,如研究主体、文化的整体性、观察角度、价值取向、工作思路、研究态度以及研究角色等为例,进行了评析.  相似文献   
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Quantitative research has resulted in inconsistent evidence for the existence of a sexual double standard, leading Crawford and Popp ( 2003 ) to issue a call for methodological innovation. The implicit association test (IAT; Greenwald, McGhee, & Schwartz, 1998 ) is a measure that may provide a means to examine the double standard without the contamination of the demand characteristics and social desirability biases that plague self-report research (Marks & Fraley, 2005 ). The purpose of this study was to examine the factors influencing explicit and implicit double standards, and to examine the relationship between these explicit and implicit double standards, and levels of socially desirable responding. One hundred and three university students completed a sexual double standard IAT, an explicit measure of the double standard, and measures of socially desirable responding. Hierarchical regression analysis indicated that levels of socially desirable responding were not related to implicit or explicit double standards. Men endorsed a stronger explicit traditional double standard than women, whereas for implicit sexual standards, men demonstrated a relatively gender-neutral evaluation and women demonstrated a strong reverse double standard. These results suggest the existence of a complex double standard, and indicate that more research of sexual attitudes should include implicit measures.  相似文献   
208.
A necessary and sufficient condition for dominant strategy implementability when preferences are quasilinear is that, for every individual i and every choice of the types of the other individuals, all k-cycles in i’s allocation graph have nonnegative length for every integer k ≥ 2. Saks and Yu (Proceedings of the 6th ACM conference on electronic commerce (EC’05), pp 286–293, 2005) have shown that when the number of outcomes is finite and i’s valuation type space is convex, nonnegativity of the length of all 2-cycles is sufficient for the nonnegativity of the length of all k-cycles. In this article, it is shown that if each individual’s valuation type space is a full-dimensional convex product space and a mild domain regularity condition is satisfied, then (i) the nonnegativity of all 2-cycles implies that all k-cycles have zero length and (ii) all 2-cycles having zero length is necessary and sufficient for dominant strategy implementability.  相似文献   
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210.
In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A partnership of local officials, agricultural development staff, and students worked with the outside team to craft a survey of agricultural traders working between northern Uganda and Southern Sudan the steps approach of a collaborative model. The goal was to create a market directory of use to producers, government officials and others interested in stimulating agricultural trade. The directory of agricultural producers and distributors served as an agricultural development and promotion tool as did the collaborative process itself.  相似文献   
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