新世纪的挑战--生物复杂性研究

复杂性是生物学的固有属性。生物学系统，从细胞到生态系统，总是包含大量的以复杂方式相互作用的部分。尽管目前我们已经获得了大量关于这些组分的数据，但是实际上对所有复杂的生物学系统，我们都缺少一个真正的定量的和综合的整体的认识。研究生物复杂性是二十一世纪科学面临的一大挑战。本文介绍了美国国家科学基金会的生物复杂性研究计划，并通过一些例子对生物复杂性研究涉及的相关方面作了探讨。     

复杂性与不确定性：无线通信面临的双重挑战

深空通信、移动通信、军事通信等领域的发展面临新的难题，其核心挑战之一在于无线通信处理中存在难以克服的各种复杂性与不确定性的问题，如何实现突破已成为当今无线通信研究的前沿热点．本文以人工智能、蜂窝无线网络等发展为启示，介绍了一种基于结构处理的研究视角，并以无线通信中信息表征和信道编码等环节为例，在分析复杂性与不确定性问题的基础上，通过相应的结构处理有效克服无线通信的相关难题，并探讨了无线通信理论与技术发展的新途径．     

ABC:一种全生命周期软件体系结构建模方法

随着计算机硬件能力的快速增长和软件应用规模的不断扩大,软件的复杂性也在持续增长,并始终制约着软件开发效率和质量的有效提升.软件的结构复杂性,尤其是高层结构的复杂性,是软件复杂性的一种重要表现.如何实现对软件高层结构复杂性的有效控制,是当前开放、动态、难控的网络环境下大规模软件系统开发与演化所面临的主要问题.针对这个问题,我们将设计阶段高层结构复杂性的控制模型―软件体系结构模型―扩展到整个软件生命周期,提出了一种以体系结构为中心的软件开发方法―ABC.该方法将软件生命周期各阶段的核心制品与活动,统一到软件体系结构模型及对其连续迭代的细化、映射和转换,实现对软件高层结构复杂性的一致、灵活、系统化的建模和管理.本文旨在系统性地总结ABC方法在软件体系结构建模方面的成果,并重点介绍近几年在协同式特征建模、运行时体系结构生成、体系结构逆向恢复与建模等方面取得的新进展.     

煤层复杂性评价理论探讨

本文通过对影响因素的分析,发现煤层复杂性是受几何类因素和安全类因素综合作用的影响,其中几何类因素占主导地位;建立了相应的评价体系和评价模型;确定了8个一级指标、46个二级评价指标和28个三级评价指标;并应用层次分析法给出了各评价指标的权重。     

基于平均增益模型的连续型(1+1)进化算法计算时间复杂性分析

连续型进化算法的计算时间复杂性分析是进化计算理论研究的一项公开难题,目前相关研究成果较少.针对连续型(1+1)EA,基于适应值差函数提出了平均增益模型及其分析方法,给出了平均计算时间的计算理论,为算法的计算时间复杂性分析提供了依据.在此基础上,研究还选取了学术界关注的球形函数作为研究对象,分别推导了变异步长满足标准正态分布和均匀分布的连续型(1+1)EA在优化球形函数时的平均增益,并估算出了它们的平均计算时间.理论分析说明:1)两种算法的计算时间复杂性都是指数级的;2)在给定相同精度和初始适应值差的前提下,采用均匀分布变异算子的算法其寻优速度优于采用标准正态分布变异算子的算法.进一步地,通过数值实验对理论分析结果进行了验证,结果表明平均增益模型分析是有效的.     

5个态变量1个端口的细胞神经网络局部活动性理论

局部活动性原理自Chua于1997年提出后,为研究耦舍细胞出现复杂现象的起因提供了有力的工具,也为预测和判定某一类局部耦合非线性系统(反应扩散细胞神经网络系统)能否展示震荡或混沌等复杂的动力学行为提供了新的必要性的判据.在实际运用中,局部活动原理只提供了一个形式的判别框架,需要针对扩散反应CNN方程"态变量"和"端口"的个数建立相应的解析判别法.本文建立了5个态变量1个端口的反应扩散细胞神经网络方程的局部活动性理论的解析判别法,并给出了相应的判别法的4个定理的证明.通过这4个定理,可以对某类具有5个变量的非线性系统的复杂性进行分析和判断.     

耐用品及其易耗部件耐用度对双寡头企业均衡产量的影响研究

为了研究耐用品双寡头企业的竞争策略，基于Bulow的耐用度选择模型，建立了存在易耗部件情况下的双寡头耐用品企业两期需求一价格模型；求得了双寡头耐用品企业租赁情况下的两期均衡产量；并运用MATLAB软件对均衡解进行仿真，分析了双寡头耐用品企业自身和对手的耐用品耐用度及易耗部件耐用度对均衡产量影响。     

半κ—规约基上的最近平面算法

把LLL规约基之间的关系推广到半κ—规约基上去，然后分析了在半κ—规约基上最近平面算法，与Babai的结果相比，提高了近似率，并具有几乎相同的时间复杂性。     

基于企业声誉的行业协会功能研究

经过30年的改革开放，行业协会成为我国政府退出或转变其行业控制权的一种制度选择。本文在文献研究的基础上，提出行业协会功能的实现，可以促进企业声誉的形成与维护。一方面，行业协会可以为企业提供交流平台，使得声誉信息可以在企业之间低成本、快速地流通；另一方面，通过行业协会专业、灵活的仲裁功能，抑制企业的机会主义倾向。     

从网络科学发展观考察多层次的高科技企业网络

本文首先简要评述网络科学的研究特点后，提出统一混合网络模型，进而从网络科学发展观出发，着重概述我们对于多层次的高科技企业网络研究的若干进展，包括高科技网络的四个层次：中关村科技园网络、全国高新科技园区网络、全国高科技企业网络和世界五百强企业网络；最后提出面临的挑战性问题及几点建议。     

企业集成创新网络合作伙伴选择模型研究

综合考虑伙伴选择过程，并对现有的方法进行改进，提出了在任务分解基础上的一种新的合作伙伴选择模型及其实现方法。该模型不仅将抽象因素和可量化因素相结合，而且将成员间竞争实力与成员间的相容性相结合，保证了输出结果的客观、公正和有效；同时因为该模型每阶段都能缩小合作伙伴的选择范围，从而避免了大量无用的复杂运算；当模型输出结果与现实情况相背离时还可采取相应的调整策略。本模型具有较好的推广应用前景。     

Why do EMD‐based methods improve prediction? A multiscale complexity perspective

Empirical mode decomposition (EMD)‐based ensemble methods have become increasingly popular in the research field of forecasting, substantially enhancing prediction accuracy. The key factor in this type of method is the multiscale decomposition that immensely mitigates modeling complexity. Accordingly, this study probes this factor and makes further innovations from a new perspective of multiscale complexity. In particular, this study quantitatively investigates the relationship between the decomposition performance and prediction accuracy, thereby developing (1) a novel multiscale complexity measurement (for evaluating multiscale decomposition), (2) a novel optimized EMD (OEMD) (considering multiscale complexity), and (3) a novel OEMD‐based forecasting methodology (using the proposed OEMD in multiscale analysis). With crude oil and natural gas prices as samples, the empirical study statistically indicates that the forecasting capability of EMD‐based methods is highly reliant on the decomposition performance; accordingly, the proposed OEMD‐based methods considering multiscale complexity significantly outperform the benchmarks based on typical EMDs in prediction accuracy.     

Philosophy,history and sociology of science: Interdisciplinary relations and complex social identities

Sociology and philosophy of science have an uneasy relationship, while the marriage of history and philosophy of science has—on the surface at least—been more successful. I will take a sociological look at the history of the relationships between philosophy and history as well as philosophy and sociology of science. Interdisciplinary relations between these disciplines will be analysed through social identity complexity theory in order to draw out some conclusions on how the disciplines interact and how they might develop. I will use the relationships between the disciplines as a pointer for a more general social theory of interdisciplinarity which will then be used to sound a caution on how interdisciplinary relations between the three disciplines might be managed.     

Is complexity a scientific concept?

Complexity science has proliferated across academic domains in recent years. A question arises as to whether any useful sense of ‘generalized complexity’ can be abstracted from the various versions of complexity to be found in the literature, and whether it could prove fruitful in a scientific sense. Most attempts at defining complexity center around two kinds of notions: Structural, and temporal or dynamic. Neither of these is able to provide a foundation for the intuitive or generalized notion when taken separately; structure is often a derivative notion, dependent on prior notions of complexity, and dynamic notions such as entropy are often indefinable. The philosophical notion of process may throw light on the tensions and contradictions within complexity. Robustness, for instance, a key quality of complexity, is quite naturally understood within a process-theoretical framework. Understanding complexity as process also helps one align complexity science with holistically oriented predecessors such as General System Theory, while allowing for the reductionist perspective of complexity. These results, however, have the further implication that it may be futile to search for general laws of complexity, or to hope that investigations of complex objects in one domain may throw light on complexity in unrelated domains.     

OFDM系统中抑制PAPR的低复杂度SLM技术

主要研究了OFDM系统峰均比抑制算法中的选择性映射算法;在此基础上提出了一种能够降低系统复杂度的改进算法:TR-SLM算法;最后采用MATLAB仿真对这传统和改进的SLM算法进行仿真,并分析了这两种算法对PAPR抑制性能以及系统复杂度的影响。仿真结果表明,改进的SLM算法能很好的达到抑制PAPR目的。     

国企治理中内部人控制的环境与机理研究

内部人控制是我国国企治理中面临的一个严峻问题.本文认为,国企治理中的内部人控制既有来自社会、文化、心理方面的宏观原因,又具体地体现着现行产权和监督体制下的当事人与监管部门的博弈;国有企业的内部人控制很难根除,但可以通过相关制度、机制的不断完善进行预防和缓解     

Modelling and knowledge transfer in complexity science

I analyse the construction and transfer of models in complexity science. Thereby, I introduce a distinction between (i) vertical model construction, which is based on knowledge about a specific target system, (ii) horizontal model construction, which is based on the alteration of an existing model and therefore does not require any references to a specific target system; and (iii) the transfer of models, which consists of the assignment of an existing model to a new target system. I argue that, in complexity science, all three of those modelling activities take place. Furthermore, I show that these activities can be divided into two general categories: (i) the creation of a repository of models without specific target systems, which have been created by large-scale horizontal construction; and (ii) the transfer of these models to particular target systems in the natural sciences, which can also be followed by an extension of the transferred model through vertical construction of adaptions and additions to its dynamics. I then argue that this interplay of different modelling activities in complexity science provides a mechanism for the transfer of knowledge between different scientific fields. It is also crucial to the interdisciplinary nature of complexity science.