A key problem of electronic commerce （for short e-commerce） is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other＇s items or none d...A key problem of electronic commerce （for short e-commerce） is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other＇s items or none do. A non-interactive optimistic fair exchange e-commerce protocol model based on the publicly verifiable secret sharing is presented. The main idea of our exchange protocol is to interchange verifiable and recoverable keys of the symmetric encryption for participants＇ items. So it is especially suitable for exchange of large-size items. Furthermore, our protocol is efficient and simple as it does not need interactive proof system which has been adopted by a large quantity of previously proposed fair exchange protocols. Based on a modified （2,2） secret sharing scheme, a concrete non-interactive fair exchange e-commerce protocol is designed.展开更多
THE long-term rise in exports has made an undeniable contribution to China＇s economic growth. As the world＇s biggest commodities trader, China＇s reliance on foreign trade was the highest among the world＇s economic...THE long-term rise in exports has made an undeniable contribution to China＇s economic growth. As the world＇s biggest commodities trader, China＇s reliance on foreign trade was the highest among the world＇s economic powers for many years.展开更多
Forum on China-Africa Cooperation prepares for the next 10 years of development AFTER a decade of robust development, the Forum on China-Africa Cooperation (FOCAC),a mechanism bridging the world’s largest developing ...Forum on China-Africa Cooperation prepares for the next 10 years of development AFTER a decade of robust development, the Forum on China-Africa Cooperation (FOCAC),a mechanism bridging the world’s largest developing country and the world’s largest developing continent,is preparing for development in the next decade with great optimism.展开更多
This year, the Fifth Ministerial Conference of the Forum on China-Africa Cooperation （FOCAC） will be held in China. Recently, Ambassador John Kayocle Shinkaiye, Chief of Staff, Bureau of the Chairperson of the Afric...This year, the Fifth Ministerial Conference of the Forum on China-Africa Cooperation （FOCAC） will be held in China. Recently, Ambassador John Kayocle Shinkaiye, Chief of Staff, Bureau of the Chairperson of the African Union Commission （AUC）, shared his thoughts with ChinAfrica reporter Liu Wei on the role that FOCAC has played in strengthening Sino-African relations, at the AU headquarters in Addis Ababa, Ethiopia. His thoughts are as follows展开更多
As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain ...As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain is connected with each other.After the development and accumulation of several decades,the new produced polyester,PTA and other plants keep展开更多
THE recent World Bank report of the continent＇s economy, ＂Africa＇s Pulse＂ laid out a very optimistic path for 2012. Coming offthe back of an average 4.9 percent growth in 2011, Sub-Saharan Africa is poised for goo...THE recent World Bank report of the continent＇s economy, ＂Africa＇s Pulse＂ laid out a very optimistic path for 2012. Coming offthe back of an average 4.9 percent growth in 2011, Sub-Saharan Africa is poised for good economic times ahead,展开更多
EACH new year promises much spirits are high, expectations large and friendships strengthened. By all accounts 2015 promises much for Sino-Affican cooperation. Admittedly, the threat of Ebola, as reported on extensive...EACH new year promises much spirits are high, expectations large and friendships strengthened. By all accounts 2015 promises much for Sino-Affican cooperation. Admittedly, the threat of Ebola, as reported on extensively in this magazine during 2014, casts a pall of negativity and tragic consequences across the continent, most notably West Africa. This killer pandemic, coupled with the perennial threat of instability and terrorism that haunts Africa, poses the biggest threat to development and the economy of the continent this year. It is little wonder then that China and Africa acknowledge the need to tightencooperation in these areas.展开更多
This paper presents an adaptive strategy called K-locking algorithm for concurrency control in database system.The algorithm integrates an optimistic approach with the K-lock mechanism to control the degree of transac...This paper presents an adaptive strategy called K-locking algorithm for concurrency control in database system.The algorithm integrates an optimistic approach with the K-lock mechanism to control the degree of transaction interference.It is shown that the K-locking strategy is adaptive to the changes in transaction parameters and outperforms both an optimistic approach and a pessimistic approach.展开更多
We consider the generalized flocking problem in multiagent systems, where the agents must drive a subset of their state variables to common values, while communication is constrained by a proximity relationship in ter...We consider the generalized flocking problem in multiagent systems, where the agents must drive a subset of their state variables to common values, while communication is constrained by a proximity relationship in terms of another subset of variables. We build a flocking method for general nonlinear agent dynamics, by using at each agent a near-optimal control technique from artificial intelligence called optimistic planning. By defining the rewards to be optimized in a well-chosen way, the preservation of the interconnection topology is guaranteed, under a controllability assumption. We also give a practical variant of the algorithm that does not require to know the details of this assumption, and show that it works well in experiments on nonlinear agents.展开更多
In this paper,we consider an optimistic nonlinear bilevel programming problem.Under some conditions,we first show that the sequence of solutions to penalty problems converges to the optimal solution of the original bi...In this paper,we consider an optimistic nonlinear bilevel programming problem.Under some conditions,we first show that the sequence of solutions to penalty problems converges to the optimal solution of the original bilevel programming problem.We then present an objective penalty method to solve such a problem.Finally,some numerical experiments are performed to illustrate its feasibility.展开更多
China’s redhot stock market is a place toharvest not only wealth, but also fame.Wang Zhongming, previously littleknown head of research with China’sstate-owned assets watchdog,became a cult hero to stock marketplaye...China’s redhot stock market is a place toharvest not only wealth, but also fame.Wang Zhongming, previously littleknown head of research with China’sstate-owned assets watchdog,became a cult hero to stock marketplayers overnight when he chal-lenged展开更多
The BRICS remain economically resilient Along with the recent economic contraction in some of the BRICS countries,the argument that this association of large emerging economies is faltering is pervasive again.In the c...The BRICS remain economically resilient Along with the recent economic contraction in some of the BRICS countries,the argument that this association of large emerging economies is faltering is pervasive again.In the current climate of global economic fragility,the BRICS have展开更多
MEMBERS of the audience listening to the melodious melody coming from the keyboards were unable to believe that the pianist had studied piano for only two months. The event was a special piano recital held on one June...MEMBERS of the audience listening to the melodious melody coming from the keyboards were unable to believe that the pianist had studied piano for only two months. The event was a special piano recital held on one June Sunday afternoon in the auditorium at the Dongcheng Normal School in Beijing. The pianists, the oldest 61 and the youngest 22, were al adult students at the Bao Huiqiao Piano Center, the first center in the country named after the famed Chinese pianist who serves as chairperson of the board. One performer, 61-year-old He Jiyuan,展开更多
Cyber threats and risks are increasing exponentially with time. For preventing and defense against these threats and risks, precise risk perception for effective mitigation is the first step. Risk perception is necess...Cyber threats and risks are increasing exponentially with time. For preventing and defense against these threats and risks, precise risk perception for effective mitigation is the first step. Risk perception is necessary requirement to mitigate risk as it drives the security strategy at the organizational level and human attitude at individual level. Sometime, individuals understand there is a risk that a negative event or incident can occur, but they do not believe there will be a personal impact if the risk comes to realization but instead, they believe that the negative event will impact others. This belief supports the common belief that individuals tend to think of themselves as invulnerable, i.e., optimistically bias about the situation, thus affecting their attitude for taking preventive measures due to inappropriate risk perception or overconfidence. The main motivation of this meta-analysis is to assess that how the cyber optimistic bias or cyber optimism bias affects individual’s cyber security risk perception and how it changes their decisions. Applying a meta-analysis, this study found that optimistic bias has an overall negative impact on the cyber security due to the inappropriate risk perception and considering themselves invulnerable by biasing that the threat will not occur to them. Due to the cyber optimism bias, the individual will sometimes share passwords by considering it will not be maliciously used, lack in adopting of preventive measures, ignore security incidents, wrong perception of cyber threats and overconfidence on themselves in the context of cyber security.展开更多
Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level...Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous.展开更多
基金This project was partially supported by the National Natural Science Foundation of China (60273049, 90104005).
文摘A key problem of electronic commerce （for short e-commerce） is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other＇s items or none do. A non-interactive optimistic fair exchange e-commerce protocol model based on the publicly verifiable secret sharing is presented. The main idea of our exchange protocol is to interchange verifiable and recoverable keys of the symmetric encryption for participants＇ items. So it is especially suitable for exchange of large-size items. Furthermore, our protocol is efficient and simple as it does not need interactive proof system which has been adopted by a large quantity of previously proposed fair exchange protocols. Based on a modified （2,2） secret sharing scheme, a concrete non-interactive fair exchange e-commerce protocol is designed.
文摘THE long-term rise in exports has made an undeniable contribution to China＇s economic growth. As the world＇s biggest commodities trader, China＇s reliance on foreign trade was the highest among the world＇s economic powers for many years.
文摘Forum on China-Africa Cooperation prepares for the next 10 years of development AFTER a decade of robust development, the Forum on China-Africa Cooperation (FOCAC),a mechanism bridging the world’s largest developing country and the world’s largest developing continent,is preparing for development in the next decade with great optimism.
文摘This year, the Fifth Ministerial Conference of the Forum on China-Africa Cooperation （FOCAC） will be held in China. Recently, Ambassador John Kayocle Shinkaiye, Chief of Staff, Bureau of the Chairperson of the African Union Commission （AUC）, shared his thoughts with ChinAfrica reporter Liu Wei on the role that FOCAC has played in strengthening Sino-African relations, at the AU headquarters in Addis Ababa, Ethiopia. His thoughts are as follows
文摘As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain is connected with each other.After the development and accumulation of several decades,the new produced polyester,PTA and other plants keep
文摘THE recent World Bank report of the continent＇s economy, ＂Africa＇s Pulse＂ laid out a very optimistic path for 2012. Coming offthe back of an average 4.9 percent growth in 2011, Sub-Saharan Africa is poised for good economic times ahead,
文摘EACH new year promises much spirits are high, expectations large and friendships strengthened. By all accounts 2015 promises much for Sino-Affican cooperation. Admittedly, the threat of Ebola, as reported on extensively in this magazine during 2014, casts a pall of negativity and tragic consequences across the continent, most notably West Africa. This killer pandemic, coupled with the perennial threat of instability and terrorism that haunts Africa, poses the biggest threat to development and the economy of the continent this year. It is little wonder then that China and Africa acknowledge the need to tightencooperation in these areas.
文摘This paper presents an adaptive strategy called K-locking algorithm for concurrency control in database system.The algorithm integrates an optimistic approach with the K-lock mechanism to control the degree of transaction interference.It is shown that the K-locking strategy is adaptive to the changes in transaction parameters and outperforms both an optimistic approach and a pessimistic approach.
基金supported by a Programme Hubert Curien-Brancusi cooperation grant(CNCS-UEFISCDI contract no.781/2014 and Campus France grant no.32610SE)supported by the Romanian National Authority for Scientific Research,CNCS-UEFISCDI(No.PNII-RU-TE-2012-3-0040)funded by the National Research Agency(ANR)project"Computation Aware Control Systems"(No.ANR-13-BS03-004-02)
文摘We consider the generalized flocking problem in multiagent systems, where the agents must drive a subset of their state variables to common values, while communication is constrained by a proximity relationship in terms of another subset of variables. We build a flocking method for general nonlinear agent dynamics, by using at each agent a near-optimal control technique from artificial intelligence called optimistic planning. By defining the rewards to be optimized in a well-chosen way, the preservation of the interconnection topology is guaranteed, under a controllability assumption. We also give a practical variant of the algorithm that does not require to know the details of this assumption, and show that it works well in experiments on nonlinear agents.
基金This work was supported by the National Natural Science Foundation of China(Nos.11501233 and 61673006)the Natural Science Research Project of Universities of Anhui Province(No.KJ2016B025).
文摘In this paper,we consider an optimistic nonlinear bilevel programming problem.Under some conditions,we first show that the sequence of solutions to penalty problems converges to the optimal solution of the original bilevel programming problem.We then present an objective penalty method to solve such a problem.Finally,some numerical experiments are performed to illustrate its feasibility.
文摘China’s redhot stock market is a place toharvest not only wealth, but also fame.Wang Zhongming, previously littleknown head of research with China’sstate-owned assets watchdog,became a cult hero to stock marketplayers overnight when he chal-lenged
文摘The BRICS remain economically resilient Along with the recent economic contraction in some of the BRICS countries,the argument that this association of large emerging economies is faltering is pervasive again.In the current climate of global economic fragility,the BRICS have
文摘MEMBERS of the audience listening to the melodious melody coming from the keyboards were unable to believe that the pianist had studied piano for only two months. The event was a special piano recital held on one June Sunday afternoon in the auditorium at the Dongcheng Normal School in Beijing. The pianists, the oldest 61 and the youngest 22, were al adult students at the Bao Huiqiao Piano Center, the first center in the country named after the famed Chinese pianist who serves as chairperson of the board. One performer, 61-year-old He Jiyuan,
文摘Cyber threats and risks are increasing exponentially with time. For preventing and defense against these threats and risks, precise risk perception for effective mitigation is the first step. Risk perception is necessary requirement to mitigate risk as it drives the security strategy at the organizational level and human attitude at individual level. Sometime, individuals understand there is a risk that a negative event or incident can occur, but they do not believe there will be a personal impact if the risk comes to realization but instead, they believe that the negative event will impact others. This belief supports the common belief that individuals tend to think of themselves as invulnerable, i.e., optimistically bias about the situation, thus affecting their attitude for taking preventive measures due to inappropriate risk perception or overconfidence. The main motivation of this meta-analysis is to assess that how the cyber optimistic bias or cyber optimism bias affects individual’s cyber security risk perception and how it changes their decisions. Applying a meta-analysis, this study found that optimistic bias has an overall negative impact on the cyber security due to the inappropriate risk perception and considering themselves invulnerable by biasing that the threat will not occur to them. Due to the cyber optimism bias, the individual will sometimes share passwords by considering it will not be maliciously used, lack in adopting of preventive measures, ignore security incidents, wrong perception of cyber threats and overconfidence on themselves in the context of cyber security.
基金supported by the National Natural Science Foundationof China (70771080)the National Science Foundation of Hubei Province(20091107)Hubei Province Key Laboratory of Systems Science in Metallurgical Process (B201003)
文摘Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous.
