T-NBC:透明的MPI非阻塞集合操作

在不修改应用程序的前提下,在MPI通信库中将阻塞的集合操作转化为非阻塞的实现可以将集合通信与紧跟在集合操作之后的计算重叠起来,从而提高应用的性能.在应用中,集合操作之后的计算包括集合通信无关的计算和集合通信相关的计算两类.集合通信可以与前者很好地重叠;由于后者需要访问通信数据,与后者的重叠和集合通信中多个集合子消息的通...     

A Study of Process Arrival Patterns for MPI Collective Operations

Process arrival pattern, which denotes the timing when different processes arrive at an MPI collective operation, can have a significant impact on the performance of the operation. In this work, we characterize the process arrival patterns in a set of MPI programs on two common cluster platforms, use a micro-benchmark to study the process arrival patterns in MPI programs with balanced loads, and investigate the impacts of different process arrival patterns on collective algorithms. Our results show that (1) the differences between the times when different processes arrive at a collective operation are usually sufficiently large to affect the performance; (2) application developers in general cannot effectively control the process arrival patterns in their MPI programs in the cluster environment: balancing loads at the application level does not balance the process arrival patterns; and (3) the performance of collective communication algorithms is sensitive to process arrival patterns. These results indicate that process arrival pattern is an important factor that must be taken into consideration in developing and optimizing MPI collective routines. We propose a scheme that achieves high performance with different process arrival patterns, and demonstrate that by explicitly considering process arrival pattern, more efficient MPI collective routines than the current ones can be obtained.     

Computer Operations: A Case of Management Neglect

Although potential payoffs from IS operations can be much greater than those from systems development, development gets most of management's IS attention. Operations consumes more than twice the budget of IS development. High-performance IS operations is often the foundation of new strategic IS applications. And users and top managers both cite operational performance when evaluating corporate IS activities. Yet operations gets little attention or recognition; this column explores this situation.     

Crisis Crowdsourcing Framework: Designing Strategic Configurations of Crowdsourcing for the Emergency Management Domain

Crowdsourcing is not a new practice but it is a concept that has gained substantial attention during recent disasters. Drawing from previous work in the crisis informatics, disaster sociology, and computer-supported cooperative work (CSCW) literature, this paper first explains recent conceptualizations of crowdsourcing and how crowdsourcing is a way of leveraging disaster convergence. The CSCW concept of “articulation work” is introduced as an interpretive frame for extracting the salient dimensions of “crisis crowdsourcing.” Then, a series of vignettes are presented to illustrate the evolution of crisis crowdsourcing that spontaneously emerged after the 2010 Haiti earthquake and evolved to more established forms of public engagement during crises. The best practices extracted from the vignettes clarified the efforts to formalize crisis crowdsourcing through the development of innovative interfaces designed to support the articulation work needed to facilitate spontaneous volunteer efforts. Extracting these best practices led to the development of a conceptual framework that unpacks the key dimensions of crisis crowdsourcing. The Crisis Crowdsourcing Framework is a systematic, problem-driven approach to determining the why, who, what, when, where, and how aspects of a crowdsourcing system. The framework also draws attention to the social, technological, organizational, and policy (STOP) interfaces that need to be designed to manage the articulation work involved with reducing the complexity of coordinating across these key dimensions. An example of how to apply the framework to design a crowdsourcing system is offered with a discussion on the implications for applying this framework as well as the limitations of this framework. Innovation is occurring at the social, technological, organizational, and policy interfaces enabling crowdsourcing to be operationalized and integrated into official products and services.     

Oil Spill: Management Crisis or Crisis Management?

Stock values and earnings of Ashland Oil and Exxon were analyzed to determine if a correlation existed between a rapid, positive management response and minimization of the financial impact following an oil spill. The results showed a positive correlation for the company that employed, what experts call, ‘good’crisis management techniques.     

Explaining the Emergence of Different European Union Crisis and Emergency Management Structures

Two European Union (EU) tools were adopted to enhance cooperation among Member States in the case of crises and emergencies (natural, industrial or man‐made) occurring both inside and outside the EU borders: first, the EU has developed a new tool in the field of civil protection that has been managed by the Directorate General Environment of the European Commission under the label of the Community Civil Protection Mechanism since 2001. Second, the Emergency and Crisis Coordination Arrangements (CCA), under the responsibility of the European Council, have been developed since 2005. Using a sociological neo‐institutionalist approach based on the concept of ‘divergent isomorphism’, the paper explains who and what the sources of EU integration process were leading to the coexistence of these two structures. Two case studies are presented using process tracing to demonstrate that two different pre‐existing organizational models were copied to create the EU structures of crisis and emergency management: that of the Community Marine pollution framework for the Community Civil Protection Mechanism and that of NATO for the CCA.     

Plague: A Challenge for Urban Crisis Management

The return of Plague, an unforgotten scourge of mankind, once again reminds us that it continues to smoulder in populations of wild rodents in natural foci throughout the world. Its occasional outbreaks remind one of the devastation it caused in the past. The 1994 outbreak in Surat caused local panic (mass hysteria) and international concern, leading to the imposition of travel and trade restrictions by a number of countries. The authenticity of the crucial decision in declaring the epidemic as ‘Plague’ and, later, different institutional initiatives taken for isolating the germ (Y. pestis) were subject to many controversies. The uniqueness of an extra band in its protein profile created much speculation among the media. This gave momentum to various notions, as to whether the disaster was natural or man‐made. In spite of all these short‐comings, the decision came to identify the epidemic as Plague and the entire catastrophic incidence was controlled within a week, with a low mortality rate. This paper traces the chronological evolution of the Plague epidemic and analyses the critical issues of its management, undertaken by various authorities and individuals, including a common citizenary. The emerging key issues of this catastrophic incident are discussed and an anatomy of the crisis is presented. The lessons learnt are put towards a model for strengthening long‐term planning against any such sudden natural or man‐made disaster.     

Quality Indicators for Crisis Communication to Support Emergency Management by Public Authorities

The purpose of this paper is to develop a framework for performance indicators to measure and improve crisis communication preparedness of public authorities. Such an instrument supporting organizational learning has not yet been developed for crisis communication. Literature is used to create a basis and the framework is derived from a process model with various phases integrating communication activities with crisis management. In the paper, the development of the instrument is explained and justified. Furthermore, an example of its use is provided in which the instrument is used for an auditor evaluation of a water contamination case. A next step for future research could be to analyze and compare a number of measurements.     

A Challenging View of Data Center Operations Management

Although the data center performs almost all of the business functions Involved In managing an entire company, few organizations offer the data center professional the respect and advancement opportunity accorded the MIS department. The data center environment can be challenging and rewarding, providing an opportunity for career advancement—but both the organization and the data center staff must recognize this fact.     

Early-Warning-Signals Management: A Lesson from the Barings Crisis

The collapse of Barings was not an isolated event of its type. Rather, it characterizes an increasingly prevalent aspect of business settings as we approach the end of the second millennium. This paper surveys theoretical references in the crisis-and-decline literature to factors triggering crises. In particular, it emphasizes perceived organizational failure to notice and act on early-warning-signals (EWS). The paper presents a framework of organizational crisis-causal factors. These factors are tabulated to form a basis for models illustrating causes of organizational crises and poor EWS management. Validity and usefulness of the framework are tested through application to the Barings crisis.The presentation of some causal factors framework provides a diagnostic/predictive tool for use by crisis management (CM) strategists and regulators. It permits the un-learning of a frequent, yet detrimental, repercussion of managerial ineptitude. The paper proceeds by, first, discussing EWS management as contributing to the CM theory base. These contributions are presented as general categories of crisis-creating and EWS management-averting factors. Categories of crisis sources and pertinent key issues are then tabulated, followed by formal propositions. Next, the paper presents, and analyses against the background of crisis-causal factors, the case of the Barings debacle of 1995. A research agenda is proposed aimed at enhancing the empirical approach to studying EWS. Finally, comment is offered on the validity of the framework presented in the paper and the ways in which it might be used by CM strategists.     

A New Approach to Crisis Management

The key to effective crisis management lies not so much with the writing of detailed manuals (that have a low likelihood of being used, and an even lower likelihood of being useful) and practising location evacuations as with structured and continuous learning processes designed to equip key managers with the capabilities, flexibility and confidence to deal with sudden and unexpected problems/events – or shifts in public perception of any such problems/events.     

The Role of Computers and Decision Aids in Crisis Management: A Developer's Report

The development of usable software for crisis-management applications is overdue. This progress report outlines a recent experience with building a proactive software program for crisis-management capabilities. Furthermore, the author reflects on the appropriate role of information technology in crisis situations, given that often information technology is the precipitating cause for corporate crises.     

Generic Expert Systems for Management Applications: The Operations Advisor and the Management Advisor

The Operations Advisor and the Management Advisor are AI-based executive decision support systems. The Operations Advisor (OA) enables managers to improve manufacturing strategy. It makes possible manufacturing policies that take full advantage of strategic interactions among capacity utilization, inventories, lead times, and unit costs.The Management Advisor (MA) values strategic business proposals (building a new plant, developing a new product, etc.). It helps managers assess the attractiveness of new business opportunities, and the impact of proposed changes in existing business policy.     

Enhancing Knowledge Management and Decision-Making Capability of China’s Emergency Operations Center Using Big Data

Emerging communication and computing technologies such as social media, Internet of Things and big data provide great opportunities to improve information management systems for emergency operations. This paper studies the issues of information management at China’s Emergency Operations Center (EOC), and proposes a data-driven knowledge management system (KMS) to support decisionmaking, coordination, and collaboration within EOCs and with the public. In the proposed KMS, big data analytics is employed to gather and analyze information from different knowledge domains and track how a crisis evolves in physical world and in cyber space. The proposed system aims at improving situation awareness of public opinions and regulating human behaviors in regards to an emergency. A case study is presented to explain how the proposed system is applied to improve decision-making during emergency.