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991.
This paper investigates the completion and the zero prime factorization for matrices over a K-Hermite ring. The authors have generalized Kaplansky’s related results, solved similar Lin-Bose problem and generalized Serre problem over a K-Hermite ring. 相似文献
992.
Hybrid systems are dynamical systems with interacting discrete computation and continuous physical processes, which have become more common, more indispensable, and more complicated in our modern life. Particularly, many of them are safety-critical, and therefore are required to meet a critical safety standard. Invariant generation plays a central role in the verification and synthesis of hybrid systems. In the previous work, the fourth author and his coauthors gave a necessary and sufficient condition for a semi-algebraic set being an invariant of a polynomial autonomous dynamical system, which gave a confirmative answer to the open problem. In addition, based on which a complete algorithm for generating all semi-algebraic invariants of a given polynomial autonomous hybrid system with the given shape was proposed. This paper considers how to extend their work to non-autonomous dynamical and hybrid systems. Non-autonomous dynamical and hybrid systems are with inputs, which are very common in practice; in contrast, autonomous ones are without inputs. Furthermore, the authors present a sound and complete algorithm to verify semi-algebraic invariants for non-autonomous polynomial hybrid systems. Based on which, the authors propose a sound and complete algorithm to generate all invariants with a pre-defined template. 相似文献
993.
Cristine Margaret R. Atienza 《Systemic Practice and Action Research》2017,30(6):569-592
This paper features the implementation of an extensive insider action research, exhaustively following the framework of Coghlan and Brannick (2010, 2014). It consisted of two action research projects - the thesis action research and the core action research - which were done in a parallel manner, both following the iterative cycles of constructing, planning, taking, and evaluating action. The thesis action research was aimed at developing a theory on building organizational identity from the viewpoint of an organizational founder. On the other hand, the core action research was focused on promoting the specific identity of the Institute for Integrality, Inc. Quality and rigor were observed in the implementation of the action research cycles. In the fieldwork, there were three main cycles undertaken – understanding organizational identity, fine-tuning the practice of this identity, and designing the integration of this identity in organizational culture. Thereafter, significant learnings were derived from meta-learning in the form of content, process, and premise reflections. Finally, through the critical reflection of the project in the light of the experience and theory, A-Founder’s Integrative Theory of Organizational Identity Building was derived. 相似文献
994.
Vikas Rai Bhatnagar 《Systemic Practice and Action Research》2017,30(4):339-376
This insider action research study differentiates between developing leaders and leadership, evolves a systemic leadership model, and intervenes on the human, social and processes dimensions for developing leadership. This is a real-time study and responds to the organizational reality of fast pace of change and its systemic nature. Consequently, the research too is fast to guide actions and influence positive changes in the organization. As the action research addresses a systemic reality, research and contributions are in multiple aspects, with new techniques having huge implications for theory building as well as improving practice. The study provides a structural solution to perceived lack of commitment in senior colleagues—a syndrome I acronym as HILE (High Intentions and Lukewarm Execution)–by re-designing organizational processes and making time available for its effective utilization in developing leadership. A new technique of triggering major changes in organizations termed “concept sublimation” distils concept from the statements of major stakeholder and sublimates it from lower to higher unit of analysis and to higher levels of positivity. Statistical simplification of a competency framework by applying concepts from Euclidian geometry and making it effective is yet a unique contribution of this action research study. The study adapts the competing values framework in developing a method of assessing cultural congruence of a candidate with the culture of the organization. The uniqueness of the study lies in bridging the gap in the literature by actually and systemically developing leadership in an organization and providing pragmatic insights on developing leadership while also creating knowledge for theory building. 相似文献
995.
Learning organisation literature has widely discussed the connections between “double-loop” learning and its significance to organisational performance, but paying little attention to tools and systems that can operationalise “double-loop” learning in organisations. This paper investigates the impact of applying a systems approach for service operations design, expressed as the Vanguard Method (Seddon, Freedom from command and control: a better way to make the work work, 2003), in order to activate “double-loop” learning in service organisations. Two case studies were conducted in the banking mortgage operations and adults’ social care services in the UK, using the dimensions of the learning organisation questionnaire (DLOQ), semi-structured interviews, observations, and documents. The findings of the cross-case analysis support the link of applying the Vanguard Method with operationalising “double-loop” learning through three main factors, namely systematic-operations improvement, organisational capacity development, and outside-in mode of work; that are all embedded into the seven dimensions of the DLOQ. The value of this paper is the introduction of a service operations design tool that can activate “double-loop” learning performance in the fast changing knowledge era. It also provides an impetus for service organisations to creatively influence employees’ competencies to effectively improve internal systems. 相似文献
996.
Zhang F.Wu Q.Zeng G. 《复杂系统与复杂性科学》2017,(1):81-87
We consider an SIRS epidemic model with a general direct immunization rate on networks. By constructing suitable Lyapunov functions, we find that the dynamical behvaior of the model is completely determined by the epidemic threshold λc. When λ≤λc, the disease-free equilibrium is globally asymptotically stable; when λ>λc, the endemic equilibrium is globally asymptotically stable. In addition, we propose a uniform direct immunization and a targeted direct immunization. The results show that under the same average immunization rate s there exists a critical immunization-lost rate δc so that the epidemic threshold of the targeted direct immunization is smaller (larger) than that of the uniform direct immunization if δ<δc(δ>δc). © 2017, The Journal of Agency of Complex Systems and Complexity Science. All right reserved. 相似文献
997.
The Kinetic Monte Carlo(KMC) is one of the commonly used methods for simulating radiation damage of materials. Our team develops a parallel KMC software named Crystal-KMC, which supports the Embedded Atom Method(EAM) potential energy and utilizes the Message Passing Interface(MPI) technology to simulate the vacancy transition of the Copper(Cu) element under neutron radiation. To make better use of the computing power of modern supercomputers, we develop the parallel efficiency optimization model for the Crystal-KMC on Tianhe-2, to achieve a larger simulation of the damage process of materials under irradiation environment. Firstly, we analyze the performance bottleneck of the Crystal-KMC software and use the MIC offload statement to implement the operation of key modules of the software on the MIC coprocessor. We use Open MP to develop parallel optimization for the Crystal-KMC, combined with existing MPI inter-process communication optimization, finally achieving hybrid parallel optimization. The experimental results show that in the single-node CPU and MIC collaborative parallel mode, the speedup of the calculation hotspot reaches 30.1, and the speedup of the overall software reaches 7.43. 相似文献
998.
COMPARISON OF TWO METHODS OF OPERATING THEATRE PLANNING: APPLICATION IN BELGIAN HOSPITAL 总被引:3,自引:0,他引:3
Sondes CHAABANE~ Nadine MESKENS~ Alain GUINET~ Marius LAURENT~ ~LAMIH laboratory Valenciennes University Valenciennes Cedex France ~MAAD Laboratory FUCAM Mons Belgium ~LIESP Laboratory INSA-Lyon France ~CHU de TIVOLI La Louvière Belgium 《系统科学与系统工程学报(英文版)》2008,17(2):171-186
Operating Theatre is the centre of the hospital management's efforts. It constitutes the most expensive sector with more than 10% of the intended operating budget of the hospital. To reduce the costs while maintaining a good quality of care, one of the solutions is to improve the existent planning and scheduling methods by improving the services and surgical specialty coordination or finding the best estimation of surgical case durations. The other solution is to construct an effective surgical case plan and schedule. The operating theatre planning and scheduling is the two important steps, which aim to make a surgical case programming with an objective of obtaining a realizable and efficient surgical case schedule. This paper focuses on the first step, the operating theatre planning problem. Two planning methods are introduced and compared. Real data of a Belgian university hospital "Tivoli" are used for the experiments. 相似文献
999.
An improved branch-and-bound algorithm to minimize the weighted flowtime on identical parallel machines with family setup times 总被引:1,自引:0,他引:1
Belgacem BETTAYEB Imed KACEM Kondo H.ADJALLAH LOSI-ICD CNRS FRE Universitéde technologie de Troyes France 《系统科学与系统工程学报(英文版)》2008,17(4):446-459
This article investigates identical parallel machines scheduling with family setup times. The objective function being the weighted sum of completion times, the problem is known to be strongly NP-hard. We propose a constructive heuristic algorithm and three complementary lower bounds. Two of these bounds proceed by elimination of setup times or by distributing each of them to jobs of the corresponding family, while the third one is based on a lagrangian relaxation. The bounds and the heuristic are incorporated into a branch-and-bound algorithm. Experimental results obtained outperform those of the methods presented in previous works, in term of size of solved problems. 相似文献
1000.
The satellite constellation classes, which are suitable for the medium earth orbit tracking and data relay satellite system (MEO-TDRSS) of China, are investigated. On the basis of the functionality and the traffic distribution characteristic of MEO-TDRSS, the coverage performance and inter-satellite link properties of four different constellation schemes are compared by simulations. Simulation results indicate that the rosette and common-track constellations, whose satellites are distributed on the celestial sphere more uniformly, are appropriate for the implementation of MEO-TDRSS of China. 相似文献