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51.
This paper explores the interrelationship between agricultural policies and development by means of a dynamically recursive, computable general equilibrium model applied to Sri Lanka. The agricultural policies investigated include elimination of the food subsidy, land reform, and technical change in agriculture. The goals considered are the levels and growth rates of GNP and employment, the distribution of income, and the real income level of the lowest income group. The study provides a quantitative assessment of the association between policies and goals and identifies the key economic mechanisms in this association. 相似文献
52.
Hira L. Koul 《Revue canadienne de statistique》1978,6(2):249-271
A class of tests is proposed for testing H0 F?(x) = e?λx, λ > 0, x≥0 vs. H1 F?(x + y) ≤ F?(x)F?(y), x, y≥0, with strict inequality for some x, y ≥ 0 (F = new is better than used). Efficiency comparisons of some tests within the class are made and a new test is proposed on the basis of these comparisons. Consistency and the asymptotic normality of the class of tests is proved under fairly broad conditions on the underlying entities. 相似文献
53.
Bela Balassa 《Journal of Policy Modeling》1980,2(3):437-455
This paper examines prospective changes in trade in manufactured goods between the industrial and the developing countries. Assuming the continuation of the policies followed by the industrial countries, it is projected that the manufactured imports of these countries from the developing countries would rise at an average annual rate of 12.5% between 1978 and 1980 while their manufactured exports would increase 9 7% a year. Nonetheless, the export surplus of the industrial countries in trade in manufactured goods would rise, contributing to the growth of industrial output. The expansion of their exports of manufactured goods would also contribute to economic growth in the developing countries, and both groups of countries would benefit from specialization according to comparative advantage. 相似文献
54.
Steven Walfish Douglas Wentz Peggy Benzing Fran Brennan Steven Champ 《Evaluation and program planning》1981,4(2):163-168
This paper reports the results of a needs assessment study conducted by a university-based alcohol abuse prevention project. Data are presented on the drinking patterns and drinking problems of a random sample of 462 students. Results suggest that students are experiencing numerous difficulties in the physical, educational, legal and psychosocial areas due to their use of alcoholic beverages. Implications for prevention and intervention programming are discussed and the need for planning programs from a data-based perspective rather than a rational and intuitive approach is stressed. 相似文献
55.
Stephen Magura 《Children and youth services review》1981,3(3):193-212
The prevention of foster care became an important issue for child welfare services during the 1970s. Two main types of prevention models have emerged: crisis intervention programs intended to prevent imminent placement and intensive service programs designed to avert those crisis situations that precipitate placement. A critical analysis of several project evaluations leads to the conclusion that neither model has been markedly successful. Low nominal project placement rates seem attributable to inability to predict placements and to client selection biases. From a strictly financial perspective, preventive services have been considerably more expensive than regular services, including temporary family foster care. Data from a new demonstration project in New Jersey illustrate various problems in providing and evaluating preventive services to families referred to protective service agencies. Implications of the findings for prevention programs and policies are discussed, and a new direction focused on truly early intervention with children and families is proposed. 相似文献
56.
通过引入自相关分析,将GM(1,1)与GM(1,N)两者的优点有机结合,运用GM(1,1)预测模型所需的数据量,达到GM(1,N)预测模型所具有的预测精度,减少灰色模型的预测误差。 相似文献
57.
肯尼思·沃尔兹的新现实主义是国际政治研究的里程碑,但学界对这一里程碑含义的理解可能存在偏差。这一理论不是国际政治研究科学化的起点,而是对古典现实主义核心论点的历史性再诠释。沃尔兹和其他古典现实主义者一样认为人的理性能力存在限度,相信实力对比是进行利益划分的客观依据,劝告政治家遵行责任伦理。古典现实主义者与沃尔兹之间的差异并没有想象的大,古典现实主义者也强调安全,他们发现国际政治中存在着安全困境,追求过多权力会导致不安全,国家追求权力应适可而止。古典现实主义者还发现世界政治中因果关系非常复杂,事件的结果绝少和当事者的动机一致,“事与愿违”是政治中的常态,这与沃尔兹强调的“系统效应”相似。新古典现实主义者试图将沃尔兹的理论进一步科学化,他们希望结合结构变量与单元变量,提出更科学的理论解释、预测国家的行为,这不仅误解了沃尔兹,也背离了现实主义传统。 相似文献
58.
Optimal string alignment is used to discover evolutionary relationships or mutations in DNA/RNA or protein sequences. Errors, missing parts or uncertainty in such a sequence can be covered with wild cards, so-called wild bases. This makes an alignment possible even when the data are corrupted or incomplete. The extended pairwise local alignment of wild card DNA/RNA sequences requires additional calculations in the dynamic programming algorithm and necessitates a subsequent best- and worst-case analysis for the wild card positions. In this paper, we propose an algorithm which solves the problem of input data wild cards, offers a highly flexible set of parameters and displays a detailed alignment output and a compact representation of the mutated positions of the alignment. An implementation of the algorithm can be obtained at https://github.com/sysbio-bioinf/swat+ and http://sysbio.uni-ulm.de/?Software:Swat+. 相似文献
59.
本试验选择朋娜脐橙(Skagg’sBonanzaNavel),在萌芽期和花芽分化期叶片施用15N硫铵,(32)P磷酸二氢纳和(15)N尿素,研究脐橙在萌芽期、初花期、生理落果期以及花芽分化期氮、磷营养吸收运转分配规律.结果表明开花这个生理过程需消耗大量氮、磷营养.同时在落花落果期,落花落果的(32)P放射比强度和NDFF%都比座果的小,说明,氮磷营养条件是引起脐橙落花落果的主要原因之一.而且,GA3+BA,GA3激素处理能吸引氮磷营养向幼果运输,此结果与GA3+BA,GA3处理提高座果率和减少落果率相一致. 相似文献
60.
研究了琥珀酸双(2-乙基己酯)磺酸钠(AOT)、甲苯(T)、乙酰胺(EM)、丙烯酰胺(AM)、N-异丙基丙烯酰胺(NIPAM)、N,N-亚甲基双丙烯酰胺(BIS)、水组成的六种微乳液体系,以电导法和目视法测定了其相区临界点电导率,并绘制了各自的拟三元相图;以偶氮二异丁腈(AIBN)为引发剂,在微乳液中制备了聚丙烯酰胺及聚N-异丙基丙烯酰胺超细微粒.用IR谱对其进行了验证,以扫描电镜观察了其外部结构特征,测得微粒平均粒径为0.05~0.10μm.实验表明,可在微乳液中制备PAM及PNIPAM超细微粒. 相似文献