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201.
分析了基于知识产权的组织间关系网络的基本内涵和构成要素,将基于知识产权的组织间关系网络的生命周期划分为5个阶段——创立阶段、成长阶段、成熟阶段、衰退阶段和解散阶段,具体论述了各阶段的组织间关系网络的演化特征。以对450家企业的深度访谈和问卷调查为基础,通过描述性统计分析、因子分析以及多元方差分析来实证研究目标一致性、信息沟通以及信任等关系属性在各阶段的传递规律。研究结果表明,基于知识产权的组织间关系属性的顶峰阶段并非都出现在关系生命周期的成熟阶段。 相似文献
202.
Inventory management (IM) performance is affected by the forecasting accuracy of both demand and supply. In this paper, an inventory knowledge discovery system (IKDS) is designed and developed to forecast and acquire knowledge among variables for demand forecasting. In IKDS, the TREes PArroting Networks (TREPAN) algorithm is used to extract knowledge from trained networks in the form of decision trees which can be used to understand previously unknown relationships between the input variables so as to improve the forecasting performance for IM. The experimental results show that the forecasting accuracy using TREPAN is superior to traditional methods like moving average and autoregressive integrated moving average. In addition, the knowledge extracted from IKDS is represented in a comprehensible way and can be used to facilitate human decision-making. 相似文献
203.
Unreliable and inaccurate property valuation has been associated with techniques currently used in property valuation. A possible explanation for these findings may be due to the utilisation of traditional valuation methods. In the current study, an artificial neural network (ANN) is applied in property valuation using the Lagos metropolis property market as a representative case. Property sales transactions data (11 property attributes and property value) were collected from registered real estate firms operating in Lagos, Nigeria. The result shows that the ANN model possesses a good predictive ability, implying that it is suitable and reliable for property valuation. The relative importance analysis conducted on the property attributes revealed that the number of servants’ quarters is the most important attribute affecting property values. The findings suggest that the ANN model could be used as a tool by real estate stakeholders, especially valuers and researchers for property valuation. 相似文献
204.
Jieun Jeon Suckchul Hong Taeyong Yang 《Technology Analysis & Strategic Management》2016,28(6):733-754
Challenges faced by the biotechnology and pharmaceutical industry, including reduced R&D productivity and the expiration of drugs that are high in demand, are recently being addressed through technological innovation. Such innovations are highly likely to change the structure and functioning of the industry. Since 2000, biotechnology and pharmaceutical companies have actively made strategic alliance, and technological innovations have changed the source of innovation from R&D to entrepreneurship within the industry. In this study, we identify the evolution of entrepreneurship and discuss the changes caused by technological advancements since 1980 by analysing patterns of exporting and acquiring technology data from Medtrack. Over difference period, biopharmaceutical firms have gained new knowledge and improved technology, and have implemented this newly acquired knowledge and innovation to introduce drugs to the market. 相似文献
205.
铁路IP数据网与综合IT网“两网融合”对提高网络资源利用率及信息化建设起着至关重要的作用.介绍铁路IP数据网与综合IT网的现状,分析“两网融合”的可行性,提出了相应的改造思路及解决方案,以适应当前铁路运输通信发展需求. 相似文献
206.
传统的无线定位方法直接应用于车辆自组织网络(VANET)时,会被窃听方利用定位信息,从而导致严重的安全隐患。为此,提出基于Bancroft方法的双群组合定位算法,用于保障车辆自组织网络中车辆定位的安全性和准确性。算法利用两个群组的智能车辆节点分别进行定位,利用两组解分别反求伪距值,如果所获得的伪距值与经过节点钟差修正后的原始伪距值基本一致,则认为这一组解为最终的定位结果,从而保证了定位的正确性。同时,双群定位的信息分散性保证了系统整体的安全性。理论分析及算法仿真表明,双群联合定位算法可使窃听方的误码率稳定在较高水平。 相似文献
207.
Due to the advantages of being able to function under harsh environmental conditions and serving as a distributed condition information source in a networked monitoring system, the fibre Bragg grating (FBG) sensor network has attracted considerable attention for equipment online condition monitoring. To provide an overall conditional view of the mechanical equipment operation, a networked service-oriented condition monitoring framework based on FBG sensing is proposed, together with an intelligent matching method for supporting monitoring service management. In the novel framework, three classes of progressive service matching approaches, including service-chain knowledge database service matching, multi-objective constrained service matching and workflow-driven human-interactive service matching, are developed and integrated with an enhanced particle swarm optimisation (PSO) algorithm as well as a workflow-driven mechanism. Moreover, the manufacturing domain ontology, FBG sensor network structure and monitoring object are considered to facilitate the automatic matching of condition monitoring services to overcome the limitations of traditional service processing methods. The experimental results demonstrate that FBG monitoring services can be selected intelligently, and the developed condition monitoring system can be re-built rapidly as new equipment joins the framework. The effectiveness of the service matching method is also verified by implementing a prototype system together with its performance analysis. 相似文献
208.
采用多元层级回归方法,对影响供应商创新能力的驱动因素以及供应商在供应链网络中的等级位置对各驱动因素与供应商创新能力间关系的调节作用进行了理论探讨和实证分析。结果显示:在跨国外包情景下,发包方支持、共享活动和联结强度对供应商的创新能力具有显著的积极影响;供应商在供应链网络中的等级位置对联结强度与供应商创新能力间关系具有显著的正向调节作用,对共享活动与供应商创新能力间关系的正向调节作用不稳定。 相似文献
209.
Giovanni Facchini Eleonora Patacchini Max F. Steinhardt 《The Scandinavian journal of economics》2015,117(2):619-649
We study immigrant assimilation by analyzing whether friendship with natives is a measure of cultural assimilation, and by investigating the formation of social ties. Using the German Socio‐Economic Panel, we find that immigrants with a German friend are more similar to natives than those without German friends, along several important dimensions, including concerns about the economy, an interest in politics, and a host of policy issues. Turning to friendship acquisition, we find that becoming employed, time spent in the host country, the birth of a child, residential mobility, and additional education acquired in the host country are significant drivers of social network variation. 相似文献
210.
针对全货运航空公司,研究其货运航线网络的构建问题。基于单分配严格枢纽航线网络,对传统模型进行改进。以各航线上货物的委托运输成本和自有机队的运输成本,取代传统的单位运输成本和折扣因子,考虑枢纽点的中转成本和载运率对路径选择的影响。结合航空货运夜航的特征考虑各机队夜间可用时间的限制,以总成本最小为目标,构建数学模型,采用LINGO优化软件求解,验证模型的有效性,为全货运航空公司构建货运航线网络提供参考。 相似文献