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Power-Based Arbitrary Decisional Actions in the Resolution of MIS Project Issues: A Project Manager's Action Research Perspective 总被引:1,自引:0,他引:1
As a management information systems (MIS) project manager and an action researcher, the author examined, over time, the influence on information system development (ISD) of the informal sociopolitical organizational actions. The paper reports two cases of action research findings concerning the effect on ISD project implementation processes of power-based arbitrary decisional actions in bureaucratic environments. The research focused on the relationship of such unilateral actions to the interconnected subprocesses of deliberate and conscious attempts by the ISD project members to define and resolve system implementation issues. A suggested conceptual framework for the issue-resolution processes (IRP's) and obstacle-coping processes (OCP's) is based on the author's IRP/OCP-related behavioral constructs and theoretical models dealing with soft-systems issues, especially appreciative system theory and soft-systems methodology, and innovative flexible, "complementarist" (Sinn, 1998) or pluralist problem-solving approaches. 相似文献
3.
基于核岭回归的非线性系统辨识及其应用 总被引:1,自引:0,他引:1
利用满足Mercer条件的核函数改进线性岭回归算法,提出一种新的直接优化的非线性核岭回归算法.与SVM算法相比,该方法的特点是通过对二次损失函数的优化计算,简化了不确定参数的数量,而且由于采用直接优化计算,能有效减少建模的时间,提高计算效率.仿真实验结果和对航煤干点的软测量应用结果都验证了该算法的有效性. 相似文献
4.
基于极限学习机的生化过程软测量建模 总被引:2,自引:0,他引:2
针对极限学习机方法隐层神经元数目过多的缺陷,提出一种改进的极限学习机方法。在单隐层前向神经网络的隐层中,增加一类分类神经元,从而形成了一种新的单隐层神经网络结构。针对不同类样本数不相同的问题,提出了处理方法,使得可以利用相同的隐层神经元对不同类的学习样本进行拟合,这使得网络的隐层神经元数目大大降低,从而简化了模型的结构,提高了神经网络的计算速度。将这一方法应用于诺西肽发酵过程,建立了菌体浓度的软测量模型,实现了菌体浓度的在线预估。 相似文献
5.
Shuyi Jia Guohong Wang Shuncheng Tan 《系统工程与电子技术(英文版)》2014,(2):183-193
The acceleration of a high maneuvering target in signal processing is helpful to enhance the performance of the tracker and facilitate the classification of targets. At present, most of the research on acceleration estimation is carried out in cases of a single target with time-frequency analysis methods such as fractional Fourier transform (FRFT), Hough-ambiguity transform (HAT), and Wigner-Vil e distribution (WVD), which need to satisfy enough time duration and sampling theorem. Only one reference proposed a method of acceleration estimation for multiple targets based on modified polynomial phase transform (MPPT) in the lin-ear frequency modulation (LFM) continuous-wave (CW) radar. The method of acceleration estimation for multiple targets in the pulse Doppler (PD) radar has not been reported so far. Compressive sensing (CS) has the advantage of sampling at a low rate and short duration without sacrificing estimation performance. There-fore, this paper proposes a new method of acceleration estimation for multiple maneuvering targets with the unknown number based on CS with pulse Doppler signals. Simulation results validate the effectiveness of the proposed method under several conditions with different duration, measurement numbers, signal to noise ra-tios (SNR), and regularization parameters, respectively. Simulation results also show that the performance of the proposed method is superior to that of FRFT and HAT in the condition of multiple targets. 相似文献
6.
胡逸萍 《兰州理工大学学报》1999,25(2):89-93
通过介绍汕头市明珠花园桩群整体抬浮及处理的情况,说明场地土大面积隆起是桩群抬浮的根本原因;并分析场地土隆起的机理,探讨避免或减少隆土的措施. 相似文献
7.
基于特征值的频谱感知算法仿真研究 总被引:1,自引:0,他引:1
频谱感知是认知无线网络中的一个重要功能,是实现其他功能的基础。研究了新型的基于特征值的感知算法,充分利用随机矩阵的渐近谱分布特性和特征值的收敛特性来设置判决门限,提高感知性能。理论分析和仿真结果均表明,新型算法性能明显优于典型的能量检测算法,克服了能量检测算法的噪声不确定性问题。Abstract: Spectrum Sensing is an important function in the cognitive radio networks.A new eigenvalue-based detection scheme for spectrum sensing was studied,and decision thresholds were set to have good performance by using the property of asymptotic spectrum distribution and convergence of maximum eigenvalue of random matrices.Theoretical analysis and simulations results show that the new detection scheme can obviously outperform the classical energy detection,and overcome the noise uncertainty problem. 相似文献
8.
研究了信用分析中的软计算方法——BP网络与自适应神经模糊推理,并对软计算方法与DEA、TOPSIS的结合运用作了进一步探讨。采用V-foldCross-validation技巧,利用样本公司实际指标数据对该模型的评分效果进行了实证研究。 相似文献
9.
In a previous paper the author introduced a concept called qualifying function as a conceptual tool for modeling and design. The concept was incorporated into the modeling phase of soft systems methodology (SSM), with the purpose of addressing some of the criticism directed toward the methodology, such as its tendency to result in regulatory, rather than radical, agendas for change. It was argued that the concept had the potential to help people in a particular problem situation to view the situation from new and different perspectives and that it could enrich the conceptual models by giving the transformation process a direction. The aim of this paper is to apply the concept, embedded in SSM, to a case study involving two projects, focused on creating new work opportunities, to explore the practical applicability and usefulness of the concept, both in general and as a part of the modeling phase of SSM. 相似文献
10.
基于多采样率数据的软测量模型 总被引:1,自引:0,他引:1
提出了一种利用具有不同采样率的过程数据建立软测量模型的方法.本文采用主成分分析技术对过程数据降维,然后用降维后的数据训练神经网络,建立软测量模型.通过仿真证明,该软测量模型结构简单,获得了过程输出变量在非采样时刻的估计值. 相似文献