A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gr...A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS method.Under some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection technique.Finally,the effectiveness and application prospects of the proposed method are verified by numerical experiments.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
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
An efficient SQP algorithm for solving nonlinear degenerate problems is proposed in the paper. At each iteration of the algorithm, a quadratic programming subproblem, which is always feasible by introducing a slack va...An efficient SQP algorithm for solving nonlinear degenerate problems is proposed in the paper. At each iteration of the algorithm, a quadratic programming subproblem, which is always feasible by introducing a slack variable, is solved to obtain a search direction. The steplength along this direction is computed by employing the 1∞ exact penalty function through Armijo-type line search scheme. The algorithm is proved to be convergent globally under mild conditions.展开更多
In this paper, we present a theoretical analysis on stability and convergence of the cautious control, which has advantages over the traditional certainty equivalence adaptive control, since it takes the parameter est...In this paper, we present a theoretical analysis on stability and convergence of the cautious control, which has advantages over the traditional certainty equivalence adaptive control, since it takes the parameter estimation error into account in the design, and is also one-step-ahead optimal in the mean square sense under Gaussian assumptions.展开更多
China’s bank credit hit a record high in the first quarter, boosted by the 4-trillion-yuan ($585-billion) stimulus plan, indicating a faster economic recovery in China compared with other countries. But Ba Shusong, D...China’s bank credit hit a record high in the first quarter, boosted by the 4-trillion-yuan ($585-billion) stimulus plan, indicating a faster economic recovery in China compared with other countries. But Ba Shusong, Deputy Director of the Research Institute of Finance under the Development Research Center of the State Council, describes China’s bank credit supplies as "excessively accommodative" from January to March.展开更多
欧元伴随1999年新年钟声而诞生。她在世界各地的国际外汇交易市场的亮相的消息成为新闻传媒的一个亮点。1999年1月4日上海一家大报的头条新闻是:上海金融界“欧元总动员”。打开1999年1月5日清晨的Internet,首先映入眼帘的消息是:欧元...欧元伴随1999年新年钟声而诞生。她在世界各地的国际外汇交易市场的亮相的消息成为新闻传媒的一个亮点。1999年1月4日上海一家大报的头条新闻是:上海金融界“欧元总动员”。打开1999年1月5日清晨的Internet,首先映入眼帘的消息是:欧元闪亮登场,美元不见惊慌。这篇文章写得精彩,信息丰富。美元,在本文称为“the worl’s most sought-after reserve currency”,对于欧元的面世,自然别有一番滋味在心头。这种微妙的心情在本文表现得淋漓尽致。当然,在种种复杂的情绪中,文章披露的两条倒也不无道理: 1....Europe might turn its back on(不理睬)Problems elsewhere in theworld economy as it concentrates on making its unprecedented currency unionwork. 2....the focus on the euro must not deflect(使偏斜)from structuralreforms to reduce sky-high unemployment rates m much of Europe. 美国人的担心(The euro will start to challenge the dollar as the world’slead currency)是否会成为现实,何时会成为现实。国人尚须拭目以待。现在就下结论,未免为时过早。 此外,本文有几处措辞极为成功,读者不妨细读慢赏。】展开更多
基金supported by the Guangxi Science and Technology base and Talent Project(AD22080047)the National Natural Science Foundation of Guangxi Province(2023GXNFSBA 026063)+1 种基金the Innovation Funds of Chinese University(2021BCF03001)the special foundation for Guangxi Ba Gui Scholars.
文摘A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS method.Under some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection technique.Finally,the effectiveness and application prospects of the proposed method are verified by numerical experiments.
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,
基金Supported by the National Natural Science Foundation of China(No.10671060)the Specialized Research Found for the Doctoral Program of Higher Education(No.20030532006)
文摘An efficient SQP algorithm for solving nonlinear degenerate problems is proposed in the paper. At each iteration of the algorithm, a quadratic programming subproblem, which is always feasible by introducing a slack variable, is solved to obtain a search direction. The steplength along this direction is computed by employing the 1∞ exact penalty function through Armijo-type line search scheme. The algorithm is proved to be convergent globally under mild conditions.
基金supported by the National Natural Science Foundation of China(Grant Nos.60221301 and 60334040)the Basic Research Funds of Beijing Institute of Technology.
文摘In this paper, we present a theoretical analysis on stability and convergence of the cautious control, which has advantages over the traditional certainty equivalence adaptive control, since it takes the parameter estimation error into account in the design, and is also one-step-ahead optimal in the mean square sense under Gaussian assumptions.
文摘China’s bank credit hit a record high in the first quarter, boosted by the 4-trillion-yuan ($585-billion) stimulus plan, indicating a faster economic recovery in China compared with other countries. But Ba Shusong, Deputy Director of the Research Institute of Finance under the Development Research Center of the State Council, describes China’s bank credit supplies as "excessively accommodative" from January to March.
文摘欧元伴随1999年新年钟声而诞生。她在世界各地的国际外汇交易市场的亮相的消息成为新闻传媒的一个亮点。1999年1月4日上海一家大报的头条新闻是:上海金融界“欧元总动员”。打开1999年1月5日清晨的Internet,首先映入眼帘的消息是:欧元闪亮登场,美元不见惊慌。这篇文章写得精彩,信息丰富。美元,在本文称为“the worl’s most sought-after reserve currency”,对于欧元的面世,自然别有一番滋味在心头。这种微妙的心情在本文表现得淋漓尽致。当然,在种种复杂的情绪中,文章披露的两条倒也不无道理: 1....Europe might turn its back on(不理睬)Problems elsewhere in theworld economy as it concentrates on making its unprecedented currency unionwork. 2....the focus on the euro must not deflect(使偏斜)from structuralreforms to reduce sky-high unemployment rates m much of Europe. 美国人的担心(The euro will start to challenge the dollar as the world’slead currency)是否会成为现实,何时会成为现实。国人尚须拭目以待。现在就下结论,未免为时过早。 此外,本文有几处措辞极为成功,读者不妨细读慢赏。】
