控制论的鲁棒调节理论用于经济系统的调节

考虑如下系统: X(t 1)=AX(t) Bu(t) Y(t)=CX(t) (1—1)式中,X(t)为n维向量,u(t)为m维向量,Y(t)为r维输出向量。 式(1—1)所示系统渐近稳定的情况下,若输入u(t)=uλ~t,则当时间t足够大时,输出Y(t)趋于C(ZI—A)~(-1)B/z=λ。如果式(1—1)所示系统不是渐近稳定的,那么可采取反馈控制的极点配置理论。极点配置理论是指实际策略u(t)要依内部变量的信息反馈来定: u(t)=KX(t) V(t) (1—2)状态反馈后的闭环系统变为 X(t 1)=(A BK)x(t) BV(t) Y(t)=CX(t) (1—3) 只要式(1—1)所示开环系统R能控,则一定存在K阵,使闭环系统渐近稳定并具有良好的品质。如果闭环输入为V(t)=uλ~t,u为常向量,则时间t足够大时:     

控制理论中的稳定性分析应用于投资系统模型产出和价格调节

我们以状态方程为基础,如下: EX(t)=AX(t) Bu(t) (1—1) Y(t)=CX(t) 在控制论中,对以上的状态方程,有以下的定义和定理: 定义1.1:考虑式(1—1)所示系统,当输入u(t)为零时,无论初值X(O)为何有限值,若成立: limx(t)=0则称该系统是渐近稳定的。 当系统输入为零时,只作自由运动,若时间足够大时,系统自由运动消失回到平衡点,则称系统为渐近稳定。     

我国铝工业“六五”期间技术进步的经济效果分析

一、铝工业技术进步的经济效果测算1.技术水平值计算技术水平值的广义技术进步测度模式如下:A(t)=(Y/L)~(1-K/Y)(K/Y)~(-K/Y)式中:A(t)——t时间的技术水平值Y——总产值L——职工总人数K——固定资产净值或固定资产原值这个公式表明,技术水平主要由两个宏观量决定:一是原测算对象的全员劳动生产率(Y/L);二是原测算的单位产值资金率     

内部收益率计算的难题与解决方法

一、项目内部收益率的含义众所周知,内部收益率是使项目从开始建设到寿命期末(或计算期末)各年净现金流量折现值之和等于零的折现率。计算式为sum from t=0 to N(CI-CO)_(jt)(1+IRR_j)~(-t)=0 (1)式中:IRR_j——项目j的内部收益率;CI_(jt)——项目j第t年的现金流入;CO_(jt)——项目j第t年的现金流出;(CI-CO)_(jt)——项目j第t     

建设项目经济评价中的销售(营业)价格判据——兼论一种新的更完善的定价策略

一、综合销售(营业)价格(P_c~t) 1.综合销售(营业)价格(P_c~t)的定义 任何建设项目都以向社会提供一定数量的产品(服务)为目的。因此,每一个建设项目(不含房地产开发项目,下同)在其生产经营期(含投产期和达产期)内的任何一年,总存在一个综合销售(营业)价格(P_c~t),使下式成立: S~t=:P_c~tQ~t 或:P_c~t=S~t/Q~t………………………………………………………………………………① 其中:S~t——项目每t年的总产出,即总销售(营业)收入。 P_c~t——项目第t年的综合销售(营业)价格。     

加快发展醋酸乙烯及其下游产品

醋酸乙烯(VAc)是重要的有机化工原料，广泛用于生产聚醋酸乙烯(PVAc)、聚乙烯醇(PVA)、涂料、浆料、胶粘剂、维纶、薄膜、乙烯基共聚树脂、缩醛树脂等化工产品。2003年全球VAc生产能力约为500万t／a。2001年全球VAc消费量为411．8万t，消费结构为：乙烯-醋酸乙烯共聚物(EVA)36．5万t，占8．9％；PVAc178．9万t，占43．4％；PVA164．5万t，占39．9％；其它产品32．0万t，占7．8％。预计2006年和2011年VAc需求量将分别达476．5万t和537．0万t，2001—2006年和2006—2011年的年均需求增长率分别为3．0％和2．4％。     

对净现值法的一点改进

净现值法是银行或企业确定最佳投资方案的科学的折现方法。所谓折现法就是把各个投资项目中未来的投资额和所获的报酬全部折算成现在的价值,然后加以比较,从中选出最优的方案的方法。 未来的现金收支折算为现值时,一般的管理会计方面的书中所采用的公式为: P=sum from t=1 to n(1/t)C_t/(1 i)~t其中:P——现值 C_t——第t期收入或支出的现金(现金净流量) i——折现率(投资报酬率) n——资金在未来期间支出或收入的次数 例如,有一投资方案A,共有4年收入,分别为300,500,500,150万元,第4年末设备的残值为30万元,假定折现率为10％,则A方案各年的现金收入现值总和为: P=300/1 10％ 500/(1 10％)~2 500/(1 10％)~3 150/(1 10％)~4 30/(1 10％)~4 =1184.14(万元) 其净现值的计算公式为:     

关于长度计量室测量环境的几点要求

温度长度是温度的函数,其关系式如下:L_t=L_(20℃){1 [α_t β(t-20℃) γ(t-20℃)~2](t-20℃)}式中 L_t——温度t时的工件长度;L20℃——温度20℃时的工件长度;α_t——温度t时工件的一次线胀系数;β——工件的二次线胀系数;γ——工件的三次线胀系数.对于机械工业中的一般测量,上式可简化为:L_t=L_(20℃)[l α_t(t-20℃)]为了有一个共同的衡量长度尺寸的温度基础,世界各国都规定了标准量的温度为20℃,我国标准     

交叉路口通行能力的分析、计算与比较

根据交通工程理论的交叉口通行能力的停车线法计算公式,一条车道的设计通行能力的计算公式如下: 公式(1)——C_s=3600/T((t_g-t_o)/t 1)φ 式中:C_3一条直行车道的设计通行能力(pcu/h);T——信号灯周期(s):     

部分期刊设备工程文献索引

宋洪勇等.履带起重机力矩限制器的使用与维护.工程机械与维修,2012(4):148—149高琦琳.CX360型挖掘机奇特故障一例.工程机械,2012(4):68—70丁建国等.180t自卸车轮边减速器机座裂纹的焊接修复.矿     

煤炭行业“以量补亏”经营策略分析

当前,经济增速放缓,下游产业需求不稳定导致煤炭市场疲软。在煤炭行业不景气的情况下,煤炭厂商普遍选择"以量补亏"的策略继续扩大生产,获得短期的现金流量来弥补固定成本和投资风险。根据古诺模型分析与思考,"以量补亏"策略并不会给企业带来最大的利润,反而加剧产能过剩,让煤炭市场雪上加霜。只有煤炭行业进行集体决策,行业自救才是缓解当前危机的良策。     

Product Development as Core Competence: How Formal Product Development Practices Differ for Radical,More Innovative,and Incremental Product Innovations

Although universally recognized as an important consideration in building product development (PD) competency, the effect of a firm's ability to vary its PD practices to develop winning products has been given scant attention in large‐scale, multiorganizational, quantitative studies. This research explores differences in formal new PD practices among three project types—incremental, more innovative, and radical. Using a sample of 380 business units, this research investigates how development practices differ across these three classes of innovation with respect to the formal PD process, project organization, PD strategy, organizational culture, and senior management commitment. Our results diverge from several commonly held beliefs about formal PD processes and the management of radical versus incremental innovations. Our results indicate that radical projects are managed less flexibly than incremental projects. Instead of being an offshoot of less strategic planning, radical projects are just as strategically aligned as incremental projects. Instead of being informally introduced entrepreneurial adventures, radical projects are often the result of more formal ideation methods. While these results may be counterintuitive to suppositional models of how to radical innovation happens, it is the central theme of this research to show how radical innovation actually happens. Our findings also provide a foundation for reexamining the role of control in the management of innovation. As the level of innovativeness increased, so too did the amount of controls imposed—e.g., less flexibility in the development process, more professional, full‐time project leadership, centralized executive oversight for new products, and formal financial assessments of expected NP performance.     

企业营销中的量价决策初探

结合具体案例介绍了在运用概率的方法定量预测市场价格的基础上，按照利润最佳、产销均衡、库存合理的原则进行量价决策的方法。     

Passion for Work,Nonwork‐Related Excitement,and Innovation Managers’ Decision to Exploit New Product Opportunities

This article investigates the role of affect in innovation managers’ decision to exploit new product opportunities—a decision central to the innovation process. The model proposes that different types of passion can trigger managers’ exploitation decisions but that this effect is contingent on experiencing excitement from events outside their work environment. A field experiment with 90 owner–managers of young firms located in an innovation context (business incubators) shows that passion for work and nonwork‐related excitement levels interdependently impact innovation managers’ decision to exploit new product opportunities. Specifically, harmonious passion has a general positive effect on managers’ propensity to exploit. In contrast, the effect of obsessive passion is more complex and contingent on the additional excitement managers experience such that the positive relationship between obsessive passion and the decision to exploit is more positive with higher levels of excitement. These findings extend the product innovation management literature by acknowledging that decision‐makers’ affective experiences influence innovation decisions and provide a first step toward understanding the role of affect and passion in the product innovation context. Second, the finding that obsessive passion and nonwork‐related excitement interact in explaining opportunity exploitation decisions highlights the need to incorporate contingency relationships in models of innovation decision‐making. Third, in drawing on a field experiment and the experimental manipulation of managerial affect during the decision‐making task, this article answers a recent call in the project management literature to pursue less common methodological approaches and develop “broader theoretical schema” in order to enhance our understanding of innovation management. Finally, this study also has implications for practitioners because it can help innovation managers understand their own decision policies. To the extent that innovation managers are able to regulate their affective experiences, this improved understanding might prevent them from premature and faulty decision‐making.     

Inventory model for an inventory system with time-varying demand rate

The standard inventory problems of the multi-period have been modeled under different situations. Specifically we have considered the demand subjects of a continuous distribution and a discrete distribution, and whether the demand of each period is unchanged or not. A method to get an economic order quantity in inventory systems with discrete and unchanged demand was presented in a previous paper, and this method has been generalized to an inventory model with varying continuous demand. However, it was not achieved due to there being many classified cases in the general situations. In this article the above method is discussed in the case discrete demand to determine whether it increases or decreases from period to period. A theoretical method is presented by using previous results and some examples are given which suggest how the concept can handle on inventory system. In order to make the decision, an algorithm is also presented under some conditions, and examples are shown by using the computer software program, Mathematica, which helps to explain the findings. In general cases, we view the optimal policy in the inventory problems in only a few periods.     

On strategic management decision processes

This paper attempts to bridge the divide between rational/analytical and behavioural/political conceptions of strategic decision making. The linkages and interactions between these approaches to the making of strategic decisions are explored in the context of a specific decision arena—strategic energy management.     

Increase your divestment effectiveness

In many large diversified corporations there is a largely prevalent habit to consider divestment decisions as ‘top secret’: information concerning potential divestitures is restricted to top management and only a handful of senior managers are involved in the decision making process. The major assumption underlying such behaviour is the fear of failure; that is, top management is concerned about involving line—generally divisional—managers in the process of making up one's mind to divest (a time consuming process as will be seen later) and searching a potential acquirer, in the fear that such involvement might work in counteractive ways and perhaps cause the abortion of the project. As a result, information is most often withheld, decisions in progress are kept secret; an ‘underground’ strategy is developed. The purpose of this article is to show that the most successful divestments are precisely those where line management's co-operation has been elicited at very early stages and to suggest that such a participative management mode is likely to produce better results. Our research, based on the study of 14 divestments in the US and Europe (see Appendix), thus shows that the division manager is a key person on the divestment chess-board and accomplishes varied missions.     

论工程量清单计价及其推广意义

通过对广东省工程量清单计价模式的认识，阐明了推广工程量清单计价的意义以及推广过程中应完善的工作。     

系统工程在校风建设中应用初探

本文运用系统科学阐明了如何认识和分析校风,同时简述了运用系统分析、系统决策等方法来建设校风,变“经验决策”为“科学决策”,从而提高了工作水平。     

Networks and the Decision to Persist with Underperforming R&D Projects

Drawing on aspiration level theory and the networks literature, this paper develops a model toward decision makers' persistence with underperforming R&D projects based on the perceived properties of their personal network. The assumption is that positive feedback from network partners motivates persistence, and that this effect is multiplied when the decision makers' network is larger and denser, when network ties are predominantly strong, and when communication frequency within the network is high. The model is tested by a field experiment and conjoint methodology. Analysis of 1632 persistence decisions nested within 51 scientists responsible for R&D projects reveals that more positive feedback enhances persistence of underperforming R&D projects, and that this effect becomes stronger with increasing network size, network density, and communication frequency. These findings extend the project management literature by focusing on the social environment of the decision maker as one so far neglected factor in empirical studies on persistence decisions. Moreover, this study is among the first to investigate contingency relationships between feedback received from network partners and network structure. Finally, while most studies have emphasized that individuals and organizations can profit from their engagements in social networks, this paper suggests a potential dark side of networks by showing that networks can encourage decision makers to persist with their investment in an underperforming—and potentially failing—project. These results can help project managers involved in networking activities to better understand the effects of these activities on their decision policies, and thus draw better and more accurate decisions. Second, this study provides insights into how organizational strategy with respect to dissemination of R&D results and involvement of the organization's R&D managers in the scientific community influences the persistence of underperforming R&D projects, and thereby the organization's R&D expenditures. This can assist top managers to design financial controls and allocate financial resources to managers of underperforming R&D projects in line with the organization's networking strategy.