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Livestock production and population census in Pakistan:Determining their relationship with agricultural GDP using econometric analysis

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Information Processing in Agriculture 2017年第2期4卷 168-177页

作者： Abdul Rehman Luan Jingdong Abbas Ali Chandio Imran Hussain college of economics and Management Anhui Agricultural UniversityChina college of economics and Management Sichuan Agricultural UniversityChina Allama Iqbal Open University Pakistan

Livestock is a subsector of Pakistan agriculture which contributes approximately 56%of value addition in agriculture and nearly 11%to the gross domestic product(GDP).Livestock production makes a major contribution to agriculture value added *** order to highlight the actual performance of livestock production and livestock and poultry products,the study explored the relationship between agricultural GDP and livestock product output,including milk,beef,mutton,poultry meat,eggs,wool,hair,skins,hides and bones,in Pakistan over the 35 year period from 1980 to *** series data were collected from the National Food Security and Research,the Economic Survey of Pakistan and the Pakistan Bureau of Statistics(various publications).Livestock data were analysed using the ordinary least squares(OLS)method and the Augmented Dickey-Fuller(ADF)test,and the results were interpreted using the Johansen co-integration *** study found that the output of milk,fat,eggs,bones and mutton has a positive,significant relationship to the agricultural GDP of Pakistan,while the output of beef,poultry meat,wool,hair,skins and hides has a negative,insignificant relationship to the agricultural GDP of ***,the study suggests that the government of Pakistan initiates new funding schemes for the development of the livestock sector.

关键词： Livestock Population census Animal husbandry Poultry OLS Agricultural GDP

Pullback Attractors for Semi-uniformly Dissipative Dynamical Systems

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Journal of Donghua University(English Edition) 2010年第5期27卷 643-648页

作者：王灵芝汪永海 Antai college of economics & Management Shanghai Jiaotong University college of Science Donghua University

The existence of pullback attractors for semi-uniformly dissipative dynamical systems under some asymptotic compactness assumptions is considered.A sufficient condition for the existence of pullback attractors is ***,... 详细信息

关键词： non-autonomous pullback attractors semi-uniform

Optimizing checkpoint for scientific simulations

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第12期13卷 891-900页

作者： Xi-sheng XIAO Ying-ping HUANG Xi-hui ZHANG economics & Management college Southwest Jiaotong University Chengdu 610031 China Industrial and Commercial college Guizhou University of Finance and Economics Guiyang 550003 China college of Business University of North Alabama Florence AL 35632 USA

It is extremely time-consuming to restart a long-running simulation from the beginning when a failure *** is a viable solution that enables simulations to be resumed from the point of *** study three models to determine the optimal checkpoint interval between contiguous checkpoints so that the total execution time is minimized and we demonstrate that optimal checkpointing can facilitate *** study greatly advances our knowledge of and practice in optimizing long-running scientific simulations.

关键词： Checkpoint Long-running Optimizing Simulation

A New Macro Model for Traffic Flow on a Highway with Bus Stop

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Communications in Theoretical Physics 2011年第6期55卷 1113-1118页

作者：唐铁桥史彦锋黄海军尚华艳 School of Transportation Science and Engineering Beihang University School of economics and Management Beihang University Information college Capital University of Economics and Business

Based on the difference between the online bus stop and the offline bus stop, two macro models are developed to describe the two types of bus stops. The numerical results show that the two models can qualitatively reproduce some complex phenomena resulted by the two types of bus stops and that the otttine bus stop is more effective than the online bus stop when the initial density is relatively low.

关键词： traffic flow bus stop stability

Does oil price affect the value of firms？ Evidence from Tunisian listed firms

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Frontiers in Energy 2016年第1期10卷 1-13页

作者： Kaouther ZAABOUTI Ezzeddine BEN MOHAMED Abdelfettah BOURI Faculty of economics and Management of Sfax University of SfaxMonastir 5046 Tunisia Department of Accounting College of Business & Economics QassimUniversity Buraidah 51431 Kingdom of Saudi Arabia

A new debate on the potential impact of oil price changes on the value of firms was initiated in this paper. Using a stochastic frontier approach, an attempt was made to derive the optimal value Q＊ of firms and calculate the Q value observed. Then the shortfall （Q＊-Q） which represents the inefficiency term was explained. Starting from 19 industrial Tunisian firms listed on the Tunis Stock Exchange between 2007 and 2011, the fact that variation of oil prices can largely explain distortions in the value of firms was empirically demonstrated.

关键词： oil price value of firm stochastic frontier approach industrial Tunisian firms

Factors influencing hybrid maize farmers' risk attitudes and their perceptions in Punjab Province,Pakistan

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Journal of Integrative Agriculture 2018年第6期17卷 1454-1462页

作者： Shoaib Akhtar LI Gu-cheng Raza Ullah Adnan Nazir Muhammad Amjed Iqbal Muhammad Haseeb Raza Nadeem Iqbal Muhammad Faisal college of economics & Management Huazhong Agricultural University Institute of Agricultural and Resource economics University of Agriculture Faisalabad The Management School Lancaster University

Hybrid maize farmers have to face diverse kinds of climate, biological, price and financial risks. Farmers＇ risk perceptions and risk attitudes are essential elements influencing farm operations and management decisions. However, this important issue has been overlooked in the contemporary studies and therefore there is a dearth of literature on this important issue. The present research is therefore, an attempt to fill this gap. This study aims to quantify hybrid maize farmers＇ perceptions of disastrous risks, their attitudes towards risk and to explore the impacts of various farm and farm household factors on farmers＇ risk attitudes and risk perceptions. The present study is conducted in four hybrid maize growing districts of Punjab Province, Pakistan, using cross-sectional data of 400 hybrid maize farmers. Risk matrix and equally likely certainty equivalent （ELCE） method are used to rank farmers＇ perceptions of four catastrophic risk sources including climate, biological, price and financial risks and to investigate farmers＇ risk aversion attitudes, respectively. Furthermore, probit regression is used to analyze the determinants affecting farmers＇ risk attitudes and risk perceptions. The results of the study showed that majority of farmers are risk averse in nature and perceive price, biological and climate to be potential sources of risks to their farm enterprise. In addition, analysis divulges that distance from farm to main market, off-farm income, location dummies for Sahiwal and Okara, age, maize farming experience, access to extension agent, significantly （either negatively or positively） influence farmers＇ risk attitudes and risk perceptions. The study delivers valuable insights for farmers, agricultural insurance sector, extension services researchers and agricultural policy makers about the local understanding of risks to hybrid maize crop in developing countries, like Pakistan, and have implications for research on farmers＇ adaptation to exposed risks.

关键词： risk perceptions risk attitude hybrid maize determinants Punjab Pakistan

The p-moment exponential robust stability for stochastic systems with distributed delays and interval parameters

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Applied Mathematics and Mechanics(English Edition) 2009年第7期30卷 915-924页

作者：苏春华刘思峰 college of economics and Management Nanjing University of Aeronautics andAstronautics college of Mathematics and Information Science Xinyang Normal University

The p-moment exponential robust stability for stochastic systems with distributed delays and interval parameters is studied. By constructing the Lyapunov- Krasovskii functional and employing the decomposition technique of interval matrix and Ito＇s formula, the delay-dependent criteria for the p-moment exponential robust stability are obtained. Numerical examples show the validity and practicality of the presented criteria.

关键词： interval matrix stochastic systems distributed delays robust stability

Grey-based approach for estimating software reliability under nonhomogeneous Poisson process

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Journal of Systems Engineering and Electronics 2022年第2期33卷 360-369页

作者： LIU Xiaomei XIE Naiming college of economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China college of Science Jiujiang UniversityJiujiang 332005China

Due to the randomness and time dependence of the factors affecting software reliability, most software reliability models are treated as stochastic processes, and the non-homogeneous Poisson process(NHPP) is the most used ***, the failure behavior of software does not follow the NHPP in a statistically rigorous manner, and the pure random method might be not enough to describe the software failure behavior. To solve these problems, this paper proposes a new integrated approach that combines stochastic process and grey system theory to describe the failure behavior of software. A grey NHPP software reliability model is put forward in a discrete form, and a grey-based approach for estimating software reliability under the NHPP is proposed as a nonlinear multi-objective programming problem. Finally, four grey NHPP software reliability models are applied to four real datasets, the dynamic R-square and predictive relative error are calculated. Comparing with the original single NHPP software reliability model, it is found that the modeling using the integrated approach has a higher prediction accuracy of software reliability. Therefore, there is the characteristics of grey uncertain information in the NHPP software reliability models, and exploiting the latent grey uncertain information might lead to more accurate software reliability estimation.

关键词： software reliability model stochastic process uncertainty system non-homogeneous Poisson process grey system theory

DYNAMIC PORTFOLIO CHOICE UNDER THE TIME-VARYING,JUMPS,AND KNIGHT UNCERTAINTY OF ASSET RETURN PROCESS

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Journal of Systems Science & Complexity 2012年第5期25卷 896-908页

作者： Chaolin HE Weidong MENG School of Management Engineering Anhui Polytechnic University college of economics and Business Administration Chongqing University

By introducing a stochastic element to the double-jump diffusion framework to measure the Knight uncertainty of asset return process, this paper builds the model of dynamic portfolio choice, which maximizes the expected utility of terminal portfolio wealth. Through specifying the state function of uncertainty-aversion, it utilizes the max-min method to derive the analytical solution of the model to study the effect of the time-varying, jumps, and Knight uncertainty of asset return process on dynamic portfolio choice and their interactions. Results of comparative analysis show： The time-varying results in positive or negative intertemporal hedging demand of portfolio, which depends on the coefficient of investor＇s risk aversion and the correlation coefficient between return shift and volatility shift; the jumps in asset return overall reduce investor＇s demand for the risky asset, which can be enhanced or weakened by the jumps in volatility; due to the existing of the Knight uncertainty, the investor avoids taking large position on risky asset, and the resulting is the improving of portfolio＇s steady and immunity. At last, an empirical study is done based on the samples of Shanghai Exchange Composite Index monthly return data from January 1997 to December 2009, which not only tests the theoretical analysis but also demonstrates that the proposed method in the paper is useful from the aspect of portfotio＇s equivalent utility.

关键词： Conditional characteristic function dynamic portfolio jumps Knight uncertainty spec-tral generalized method of moments time-varying.