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排序方式: 共有511条查询结果,搜索用时 15 毫秒
1.
Deepmala Gupta Arvind Kumar Dwivedi Madhu Tripathi 《Lakes & Reservoirs: Research and Management》2019,24(4):391-393
Knowledge of the length–weight relationships (LWRs) of fish is an important tool to understand fish body form, growth pattern, stock management and their conservation. The present study focused on investigating the length–weight relationships for five catfish species, Pachypterus atherinoides (Bloch, 1794), belonging to family Horabagridae; Batasio batasio (Hamilton, 1822) family Bagridae; Bagarius yarrelli (Sykes, 1839), family Gogangra viridescens (Hamilton, 1822); and Sisor rhabdophorus (Hamilton, 1822) belonging to family Sisoridae. Specimens were collected from the middle stretch of the Ganga River in India from November 2016 to May 2018. A total of 174 specimens of five fish species were collected, and their total lengths were measured to the nearest centimetre and the body weight to the nearest gram. The value of the parameter slope (b) of LWRs of the five species ranged from 2.86 (B. yarrelli) to 3.16 (G. viridescens), with a mean value of 2.99. The results of the present study documented the new maximum total length (TL) for P. atherinoides and S. rhabdophorus. The present study also provides the first reference regarding LWRs for S. rhabdophorus. 相似文献
2.
Because of undesirable side effects of chemical methods pulsed underwater corona discharges are emerging as a potential future advanced oxidation process (AOP) for water disinfection. In pulsed corona discharges a discharge channel is created, which contains a non-thermal plasma with a low degree of ionisation and low electron densities, but with electron energies of up to 10 eV. It has been demonstrated that electrons with this energy can dissociate water and oxygen molecules and produce various reactive radicals (*OH, H*, O*, HO2*), molecular species (H2O2, H2, O2), ultraviolet radiation and shock waves. It is supposed that the combination of all effects leads to a very efficient killing of microorganisms. To understand this in detail and to improve the efficiency of the overall system there is the need to develop suitable diagnostic methods for the quantitative determination of the various oxidants produced during the discharge. In this paper we present preliminary experimental results obtained with different chemical probes for *OH radicals, and H2O2 produced by pulsed corona discharges. 相似文献
3.
In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied. 相似文献
4.
This article examines the debate on reforms in industrial relations law in India, needed to support its economic liberalisation programme. Analysing a distinctively Indian experience of state intervention in industrial relations, it concludes that the thrust of the reform should be towards entrusting union recognition and promotion of dispute settlement to an authority that is independent of the state executive. 相似文献
5.
6.
Summary In the study of information theoretic measures, additivity has been the basic requirement. However it is quite interesting to investigate the sub-additive measures. Starting from subadditivity for measures associated with a pair of distributions of a discrete random variable, it has been changed into an equality relation using another function of a pair of distributions., Under the sum property of the function and the measures, the relation is expressed in terms of a functional equation of which the most general complex solutions have been obtained. In terms of the real continuous solutions of the functional equation, the sub-additive measures of Relative information and Inaccuracy have been defined and characterized. Particular cases and simple properties particularly the convexities of some of these new measures have also been studied. 相似文献
7.
B. C. Gupta 《Metrika》1973,20(1):209-214
Summary In this paper, relationships between generalizedh-statistics which estimate powers and products of central moments unbiasedly and the polykays by using ordered partitions are established. A table expressing generalizedh-statistics of weight 12 in terms of polykays and vice versa is presented. Expressions of weight less than 12 are obtained from this table.
This research has been supported by a grant from FINEP/Ministério do Planejamento e Coordenacão Geral to the IMUFRJ. 相似文献
Zusammenfassung In der vorliegenden Arbeit wird mittels geordneter Zerlegungen eine Beziehung zwischen verallgemeinerterh-Statistik, welche Potenzen und Produkte von zentralen Momenten erwartungstreu abschätzt, und polykays hergestellt. Eime Tabele mit verallgemeinerterh-Statistik vom Gewicht 12 in polykay-Termen, und umgekehrt, wird gegeben. Gewichtsausdrücke kleiner als 12 werden aus dieser Tabelle gewonnen.
This research has been supported by a grant from FINEP/Ministério do Planejamento e Coordenacão Geral to the IMUFRJ. 相似文献
8.
This note analyses the effect of the policy of tightening Intellectual Property Rights (IPR) on the rate of innovation in
the North and on the welfare in both North and South in a model which is otherwise identical to Helpman (1993) except in the
concept of knowledge capital. We assume that the South based imitated products do not contribute to the knowledge capital
in the North. It is shown that the tightening of IPR raises the rate of innovation in the North and may improve the welfare
of both North and South. These results are significantly different from those in Helpman (1993). 相似文献
9.
Sunil Gupta 《Marketing Letters》1994,5(1):5-17
This paper examines the role of managerial judgment in forming a final forecast, or judging the achievability of a critical level of sales, when multiple forecasts or opinions are available to the decision maker. Several factors that can help improve the quality of human intervention are identified and incorporated in a decision aid. Experimental results show that aided combination can help the decision maker exploit her relevant private information and mitigate the generally observed negative effects of human intervention. Further, the results suggest that emphasizing expected sales, even when the organization is primarily interested in go/no-go decisions, helps improve performance. Several suggestions for future research are presented.
相似文献
10.
Gupta MR 《Journal of development economics》1993,41(1):137-151
"A theoretical model of rural-urban migration has been developed with special reference to the informal sector. The wage rate and employment in the informal sector are determined endogenously. The paper shows the simultaneous existence of open unemployment and informal sector in the urban area in migration equilibrium. The effects of alternative subsidy policies on unemployment and welfare of the workers are studied." The model is intended primarily for use in analyzing trends and policies in developing countries. 相似文献