To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, t...To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, the long-term debt ratio was adopted as the measure of the capital structure, and the total asset growth and sales growth were chosen to measure the growth of high-tech firms. Regression analysis shows that there is a significant relationship between environment risk, growth and performance of hightech firms measured by the return on equity and cash flow, respectively.展开更多
奇异值分解(Singular value decomposition,SVD)作为一种有效的信号降噪方法广泛应用于旋转机械振动信号周期性瞬态冲击提取中。传统SVD以能量为导向,无法提取出能量较弱但含故障信息丰富的奇异分量(Singular Component,SC)。为此,提出...奇异值分解(Singular value decomposition,SVD)作为一种有效的信号降噪方法广泛应用于旋转机械振动信号周期性瞬态冲击提取中。传统SVD以能量为导向,无法提取出能量较弱但含故障信息丰富的奇异分量(Singular Component,SC)。为此,提出加权firm阈值奇异值分解(Weighted Firm Singular Value Decomposition,WFSVD)方法。该方法首先引入平方包络谱峭度(Squared Envelope Spectrum Kurtosis,SESK)作为量化故障敏感度的指标,以评估各个SC所含故障信息的丰富程度;其次,将SESK作为权重因子引入到基于firm阈值的SC去噪中,设计基于SESK的加权firm阈值SC去噪策略;最后,重构信号,实现信号降噪并有效提取故障特征。对于仿真信号与试验数据的分析验证了所提方法在周期性微弱瞬态冲击提取及旋转机械故障诊断中的有效性。展开更多
Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface dur...Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface during low-velocity impact.In this investigation,the firm embedding behavior of AGP was observed by impact experiments.Corresponding numerical simulations provided a better understanding of this process.Experimental and numerical results indicated that the firm embedding behavior of AGP was mainly due to the filling-material in the groove rather than the friction between the projectile and target,unlike traditional shape such as conical projectile.According to observation,firm embedding process can generally be subdivided into four stages:initial-cratering stage,groove-filling stage,fillingmaterial failure stage and rebound vibration stage.Moreover,the damage mechanics of target material around crater was obtained through microscopic tests.A comparison of the cross-sectional figures between the experiment and simulation proved that the analysis and the proposed method were reasonable and feasible,which further demonstrated that the firm embedding behavior has application potential in new concept warheads.展开更多
Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much infor...Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much information a pedestrian can perceive,thus the number of pedestrians within the visual field can be used to estimate waiting time at the exit.Besides,the choice firmness that reflects the degree to which a pedestrian would persist in his/her previous choice of exit is proposed.By integrating game theory into a cellular automata simulation framework,the pedestrian exit choice mechanism is investigated and explicitly modeled in this paper.A systematic analysis of the key factors influencing pedestrian evacuation is conducted,including visual radius and choice firmness of a pedestrian,initial crowd distribution of the room,exit layout as well as exit width.It is found that low choice firmness level can lead to unnatural pedestrian behavior such as wandering,which is adverse to evacuation.The longer the pedestrian's visual radius,the earlier the pedestrian can determine his/her final selection of the exit.Compared with the scenario where the pedestrians are randomly distributed,pedestrians clustered together in a corner of the room lead to high crowd density and imbalanced use of exits.Furthermore,the exit layout and exit width also have a certain influence on pedestrian evacuation process.The results of this paper may be of benefit to the formulation of behavioral rules in other pedestrian simulation models.展开更多
Aiming at the deficiency of exterminating measures of Chinese firm safety management, a simulation model of Chinese firm＇s safety management capability based on the organizational learning theory, in which the simula...Aiming at the deficiency of exterminating measures of Chinese firm safety management, a simulation model of Chinese firm＇s safety management capability based on the organizational learning theory, in which the simulation method of system dynamics is utilized. The level variable and rate variable are designed based on the practical situation and change situation of corresponding variables of firm＇s safety management ca- pability. Simulation firms are built with accident case groups of the oil industry, chemical industry, machine industry, coal mining industry, and weapon industry. Through analyzing the simulation result, the growth law of Chinese firm＇s safety management capability is obtained as follows： the accumulating and the coupling of safety knowledge should be emphasized at the same time; the balance of learning behavior of individual, group and organization should be considered together; different types of Chinese firm should take different safety policies according to their practical situations.展开更多
The relationship between options and agency costs in levered firms is studied by modeling the effect of executive stock options on the manager's investment strategy in levered firms. Stock options do not necessari...The relationship between options and agency costs in levered firms is studied by modeling the effect of executive stock options on the manager's investment strategy in levered firms. Stock options do not necessarily aggravate agency costs in levered firms. The corporate governance affects agency costs greatly. If debt-holders were entitled to design executive stock options together with stockholders, by allocating power properly between stockholders and debt-holders, firm value could be enhanced greatly. The following way of allocating power between the two parties is proposed: the exercise price should be the weighted average of the stockholders' and debt-holders' suggested exercise prices. The weight allocated to debt-holders is positively related to the amount of debts that debt-holders lend to stockholders.展开更多
Recent studies in complexity science have uncovered temporal regularities in the dynamics of impact along scientific and other creative careers, but they did not extend the obtained insights to firms. In this paper, w...Recent studies in complexity science have uncovered temporal regularities in the dynamics of impact along scientific and other creative careers, but they did not extend the obtained insights to firms. In this paper, we show that firms' technological impact patterns cannot be captured by the state-of-the-art dynamical models for the evolution of scientists' research impact, such as the Q model. Therefore, we propose a time-varying returns model which integrates the empiricallyobserved relation between patent order and technological impact into the Q model. The proposed model can reproduce the timing pattern of firms' highest-impact patents accurately. Our results shed light on modeling the differences behind the impact dynamics of researchers and firms.展开更多
Increasing attention has been focused on the extent to which corporate political connections influence the growing pollution due to the rapid growth in the popularity of firm pollution in developing countries.We adopt...Increasing attention has been focused on the extent to which corporate political connections influence the growing pollution due to the rapid growth in the popularity of firm pollution in developing countries.We adopt a static threshold regression model to investigate the effects of heterogeneous environmental regulation on political connections and firm pollution based on the panel data from China’s A-share listed companies from 2012 to 2019.The empirical results show a non-linear relationship between the degree of political connection of listed company executives and the level of firm pollution.And the relationship between the two roughly presents a U-shaped relationship under the action of the marketincentive environmental regulation threshold.However,it roughly presents an inverted N-shaped relationship under the action of the command-control environmental regulation threshold.Additionally,the group test results show that the existence of regional and ownership heterogeneity causes certain differences in the environmental behaviour of politically connected enterprises.These findings indicate that diverse environmental regulations are needed to promote sustainable green development and to further expand the theoretical and practical exploration of political connections on firm pollution.展开更多
China National Offshore Oil Co. (CNOOC) and two other companies had jointly signed two new production-sharing contracts to explore offshore oil and natural gas fields in Myanmar. CNOOCs Myanmar Ltd., China Huanqiu ...China National Offshore Oil Co. (CNOOC) and two other companies had jointly signed two new production-sharing contracts to explore offshore oil and natural gas fields in Myanmar. CNOOCs Myanmar Ltd., China Huanqiu Contracting and Engineering Corp. and Golden Aaron Pte. Ltd. of Singapore had signed contracts with展开更多
China and Kazakhstan are reviewing the possibil-ity of building a pipeline to deliver natural gas fromwestern Kazakhstan to Xinjiang Uygur AutonomousRegion,on China’s western border,to satisfy the
With the measurement of dividend payout ratio, logistic regression index value and the firm size financing constraints, this paper investigated the investment behavior of China’s manufacturing firms over the period f...With the measurement of dividend payout ratio, logistic regression index value and the firm size financing constraints, this paper investigated the investment behavior of China’s manufacturing firms over the period from 1998 to 2003, and the relationship between financing constraints and corporate investment using the OLS regression method. The empirical evidence shows that there are certain extent financing constraints in China’s manufacturing firms, but the results are different with different variables to measure the financing constraints.展开更多
ZTE Corporation, a publicly-listed global provider of telecommunications equipment and network solutions, has become the first Chinese telecom company to be issued with a CC （Common Criteria for IT security evaluatio...ZTE Corporation, a publicly-listed global provider of telecommunications equipment and network solutions, has become the first Chinese telecom company to be issued with a CC （Common Criteria for IT security evaluation） security certificate.展开更多
Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditiona...Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditionally seen as vital to understand the incentives for research and development activities in firms. However, they do not fully define the technology regimes, when one asks how the knowledge based firm competes. Therefore, the dynamic nature of firm capabilities and knowledge development in terms of expansion and in terms of deepening are also discussed. These two additional aspects of knowledge implies that even if all firms in an industry can be considered to be knowledge intensive these firms do also differ. Using cases of entrepreneurial start-up firms in Sweden, we illustrate whether our conceptual ideas of knowledge development help us understand the diversity and contradictions of firm evolution. Our finding is that firm evolution and capability development is dependent upon both the potential for expanding knowledge, such as by innovations, and by deepening the understanding within established knowledge, such as by learning. This implies that the shaping of a science based industry must be seen in relation both to the value of current knowledge and capabilities together with the sometimes only limited and temporarily advantages of radical innovations.展开更多
基金The Fok Ying-Tong Education Founda-tion for Young Teachers in the Higher Education Institutions of China (No101084)Science and Technology Foundationof Liaoning Province (No1051354)
文摘To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, the long-term debt ratio was adopted as the measure of the capital structure, and the total asset growth and sales growth were chosen to measure the growth of high-tech firms. Regression analysis shows that there is a significant relationship between environment risk, growth and performance of hightech firms measured by the return on equity and cash flow, respectively.
基金financially supported by the National Natural Science Foundation of China [grant number 11472053]
文摘Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface during low-velocity impact.In this investigation,the firm embedding behavior of AGP was observed by impact experiments.Corresponding numerical simulations provided a better understanding of this process.Experimental and numerical results indicated that the firm embedding behavior of AGP was mainly due to the filling-material in the groove rather than the friction between the projectile and target,unlike traditional shape such as conical projectile.According to observation,firm embedding process can generally be subdivided into four stages:initial-cratering stage,groove-filling stage,fillingmaterial failure stage and rebound vibration stage.Moreover,the damage mechanics of target material around crater was obtained through microscopic tests.A comparison of the cross-sectional figures between the experiment and simulation proved that the analysis and the proposed method were reasonable and feasible,which further demonstrated that the firm embedding behavior has application potential in new concept warheads.
基金the National Natural Science Foundation of China(Grant No.71904116)the Fund from the Shanghai Municipal Commission of Science and Technology,China(Grant Nos.19DZ1209600 and 18DZ1201500)。
文摘Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much information a pedestrian can perceive,thus the number of pedestrians within the visual field can be used to estimate waiting time at the exit.Besides,the choice firmness that reflects the degree to which a pedestrian would persist in his/her previous choice of exit is proposed.By integrating game theory into a cellular automata simulation framework,the pedestrian exit choice mechanism is investigated and explicitly modeled in this paper.A systematic analysis of the key factors influencing pedestrian evacuation is conducted,including visual radius and choice firmness of a pedestrian,initial crowd distribution of the room,exit layout as well as exit width.It is found that low choice firmness level can lead to unnatural pedestrian behavior such as wandering,which is adverse to evacuation.The longer the pedestrian's visual radius,the earlier the pedestrian can determine his/her final selection of the exit.Compared with the scenario where the pedestrians are randomly distributed,pedestrians clustered together in a corner of the room lead to high crowd density and imbalanced use of exits.Furthermore,the exit layout and exit width also have a certain influence on pedestrian evacuation process.The results of this paper may be of benefit to the formulation of behavioral rules in other pedestrian simulation models.
基金the National Social Science Foundation of China (07BJY080)
文摘Aiming at the deficiency of exterminating measures of Chinese firm safety management, a simulation model of Chinese firm＇s safety management capability based on the organizational learning theory, in which the simulation method of system dynamics is utilized. The level variable and rate variable are designed based on the practical situation and change situation of corresponding variables of firm＇s safety management ca- pability. Simulation firms are built with accident case groups of the oil industry, chemical industry, machine industry, coal mining industry, and weapon industry. Through analyzing the simulation result, the growth law of Chinese firm＇s safety management capability is obtained as follows： the accumulating and the coupling of safety knowledge should be emphasized at the same time; the balance of learning behavior of individual, group and organization should be considered together; different types of Chinese firm should take different safety policies according to their practical situations.
文摘The relationship between options and agency costs in levered firms is studied by modeling the effect of executive stock options on the manager's investment strategy in levered firms. Stock options do not necessarily aggravate agency costs in levered firms. The corporate governance affects agency costs greatly. If debt-holders were entitled to design executive stock options together with stockholders, by allocating power properly between stockholders and debt-holders, firm value could be enhanced greatly. The following way of allocating power between the two parties is proposed: the exercise price should be the weighted average of the stockholders' and debt-holders' suggested exercise prices. The weight allocated to debt-holders is positively related to the amount of debts that debt-holders lend to stockholders.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61673150 and 11622538)financial support from the URPP Social Networks at the University of Zurich+1 种基金the UESTC professor research start-up (Grant No. ZYGX2018KYQD215)the Science Strength Promotion Programme of UESTC,Chengdu。
文摘Recent studies in complexity science have uncovered temporal regularities in the dynamics of impact along scientific and other creative careers, but they did not extend the obtained insights to firms. In this paper, we show that firms' technological impact patterns cannot be captured by the state-of-the-art dynamical models for the evolution of scientists' research impact, such as the Q model. Therefore, we propose a time-varying returns model which integrates the empiricallyobserved relation between patent order and technological impact into the Q model. The proposed model can reproduce the timing pattern of firms' highest-impact patents accurately. Our results shed light on modeling the differences behind the impact dynamics of researchers and firms.
基金This work was supported by National Natural Science Foundation of China[No.72091515]the Natural Science Fund of Hunan Province(2022JJ40647).
文摘Increasing attention has been focused on the extent to which corporate political connections influence the growing pollution due to the rapid growth in the popularity of firm pollution in developing countries.We adopt a static threshold regression model to investigate the effects of heterogeneous environmental regulation on political connections and firm pollution based on the panel data from China’s A-share listed companies from 2012 to 2019.The empirical results show a non-linear relationship between the degree of political connection of listed company executives and the level of firm pollution.And the relationship between the two roughly presents a U-shaped relationship under the action of the marketincentive environmental regulation threshold.However,it roughly presents an inverted N-shaped relationship under the action of the command-control environmental regulation threshold.Additionally,the group test results show that the existence of regional and ownership heterogeneity causes certain differences in the environmental behaviour of politically connected enterprises.These findings indicate that diverse environmental regulations are needed to promote sustainable green development and to further expand the theoretical and practical exploration of political connections on firm pollution.
文摘China National Offshore Oil Co. (CNOOC) and two other companies had jointly signed two new production-sharing contracts to explore offshore oil and natural gas fields in Myanmar. CNOOCs Myanmar Ltd., China Huanqiu Contracting and Engineering Corp. and Golden Aaron Pte. Ltd. of Singapore had signed contracts with
文摘China and Kazakhstan are reviewing the possibil-ity of building a pipeline to deliver natural gas fromwestern Kazakhstan to Xinjiang Uygur AutonomousRegion,on China’s western border,to satisfy the
基金Funded by the Natural Science Foundation of China (No. 70372041).
文摘With the measurement of dividend payout ratio, logistic regression index value and the firm size financing constraints, this paper investigated the investment behavior of China’s manufacturing firms over the period from 1998 to 2003, and the relationship between financing constraints and corporate investment using the OLS regression method. The empirical evidence shows that there are certain extent financing constraints in China’s manufacturing firms, but the results are different with different variables to measure the financing constraints.
文摘ZTE Corporation, a publicly-listed global provider of telecommunications equipment and network solutions, has become the first Chinese telecom company to be issued with a CC （Common Criteria for IT security evaluation） security certificate.
文摘Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditionally seen as vital to understand the incentives for research and development activities in firms. However, they do not fully define the technology regimes, when one asks how the knowledge based firm competes. Therefore, the dynamic nature of firm capabilities and knowledge development in terms of expansion and in terms of deepening are also discussed. These two additional aspects of knowledge implies that even if all firms in an industry can be considered to be knowledge intensive these firms do also differ. Using cases of entrepreneurial start-up firms in Sweden, we illustrate whether our conceptual ideas of knowledge development help us understand the diversity and contradictions of firm evolution. Our finding is that firm evolution and capability development is dependent upon both the potential for expanding knowledge, such as by innovations, and by deepening the understanding within established knowledge, such as by learning. This implies that the shaping of a science based industry must be seen in relation both to the value of current knowledge and capabilities together with the sometimes only limited and temporarily advantages of radical innovations.
