Sharif Digital Repository

In a deregulated electric power utility industry in which a competitive electricity market can influence system reliability, market risks cannot be ignored. This paper (1) proposes an analytical probabilistic model for reliability evaluation of competitive electricity markets and (2) develops a methodology for incorporating the market reliability problem into HLII reliability studies. A Markov state space diagram is employed to evaluate the market reliability. Since the market is a continuously operated system, the concept of absorbing states is applied to it in order to evaluate the reliability. The market states are identified by using market performance indices and the transition rates... 

On pool market structure, the generating units are typically dispatched in order of lowest to highest bid as needed to meet demand requirement as well as considering network constraints. Generally, no account is taken of generating unit's reliability when scheduling them. This paper proposes a new structure for electricity market to consider generating unit's reliability in the scheduling problem. GAMS (General Algebraic Modeling System) language has been used to solve the social welfare maximization problem using CPLEX optimization software with mixed integer programming. ©2006 IEEE  

In parallel with enhancements in the technology of integrated circuits, transistors are implemented in silicon. Though the price is reduced; design is more complicated, which create the efficiency and power consumption. The reason why modern GDI-based circuit is the focus of attention is that in designing digital circuit, less power is required while more efficiency is obtained. Lowering the complexity of logic circuit can bring about reduction of power consumption, propagation delay and decrease circuit space. GDI-based integrated circuit resembles MOSFET transistors but have fewer transistors and higher performance capability. This study addresses two main areas which are Studying and... 

In this work we introduce Heterogeneous Interconnect for Low Resolution Cache Access (Helia). Helia improves energy efficiency in snoop-based chip multiprocessors as it eliminates unnecessary activities in both interconnect and cache. This is achieved by using innovative snoop filtering mechanisms coupled with wire management techniques. Our optimizations rely on the observation that a high percentage of cache mismatches could be detected by utilizing a small subset but highly informative portion of the tag bits. Helia relies on the snoop controller to detect possible remote tag mismatches prior to tag array lookup. Power is reduced as a) our wire management techniques permit slow... 

The decentralized security management in a pervasive computing environment' requires apportioning the environment into several security domains. In each security domain' an administrator (we call it authority) is responsible for specifying the security policies of the domain. Overlapping of security domains results in the requirement of cooperative security management in the shared/ overlapping domains. To satisfy this requirement' we propose an abstract security model' as well as its supplementary calculus of composite authorities. The security model is based on deontic logic and is independent of the domains' heterogeneity. The model's policy language (we call it MASL) enables multiple... 

Fifteen years after introduction of Business Process Reengineering (BPR) and a series of successful and not-so-successful BPR implementation, a revised methodology is needed to incorporate cases of major and sudden organizational or environmental changes with BPR. The new methodology can also be particularly applicable to project oriented businesses. September 11, Tsunami, and other major world events show that nothing is constant but change. A reengineered process may only stay as the environment factors stay the same. Therefore, the processes can no longer be the central focus of reengineering, but the output needs. Technology has enabled us to refocus and apply reengineering constantly to... 

Purpose - Aims to describe design, prototyping and characteristics of a pole climbing/manipulating robot with ability of passing bends and branches of the pole. Design/methodology/approach - Introducing a hybrid (parallel/serial) four degree of freedom (DOF) mechanism as the main part of the robot and also introduces a unique gripper design for pole climbing robots. Findings - Finds that a robot, with the ability of climbing and manipulating on poles with bends and branches, needs at least 4 DOFs. Also an electrical cylinder is a good option for climbing robots and has some advantages over pneumatic or hydraulic cylinders. Research limitations/implications - The robot is semi-industrial... 

Roadmapping, a tool of strategic planning, visualize where and how an organization will be in the future. Visualization of strategic programs assists people in the organization to understand the strategy which is a key for implementing strategy successfully. A generic roadmap is included of three main layers such as; market, product and technology. Decision making in each layer are done separately because of the nature of each layer. Therefore, decisions in roadmapping can be done with different tools. Whiles, decisions in each layer of the roadmap cannot be done without considering the upper or lower layer decisions. In this study we propose Fuzzy PROMETHEE method for integrating decisions... 

In this work we propose using heterogeneous interconnects in power-aware chip multiprocessors (also referred to as Helia). Helia improves energy efficiency in snoop-based chip multiprocessors as it eliminates unnecessary activities in both interconnect and cache. This is achieved by using innovative snoop filtering mechanisms coupled with wire management techniques. Our optimizations rely on the observation that a high percentage of cache mismatches could be detected by utilizing a small subset but highly informative portion of the tag bits. Helia comes in two variations: source-based (S-Helia) and destination-based (D-Helia). S-Helia relies on a global snapshot of remote caches collected in... 

This article deals with technology strategy and its linkage with overall strategy at multi-business, diversified groups. In the last two decades, the alignment of technology and business strategy has been one of the important research fields in strategy and technology management scopes. These researchs has been concentrated on single companies through which different frameworks, models & decision support tools have been developed and widely utilized by industries. Although multi-business and diversified groups play an important role in global and national economics and need a comprehensive and overall plan for the management of their diversified technological assets, there are few researchs... 

Graphics Processing Units (GPUS) are widely used as the accelerator of choice for applications with massively data-parallel tasks. However, recent studies show that GPUS suffer heavily from resource underutilization, which, combined with their large static power consumption, imposes a significant power overhead. One of the most power-hungry components of a GPU-the execution units-frequently experience idleness when (1) an underutilized warp is issued to the execution units, leading to partial lane idleness, and (2) there is no active warp to be issued for the execution due to warp stalls (e.g., waiting for memory access and synchronization). Although large in total, the idle time of... 

It is beyond dispute that technological change acts as a driver of economic growth. In developing countries where highly suffer from lack of this process, incremental innovation is considered as main source of technology capability building and development In moving toward this pass and to meet with time pressure of catching up, developing countries acquire the initial required knowledge base through technology absorption from outside sources; On the other hand as development is a lengthy process, it is important that the absorbed knowledge still has the potential of more advancement in future. Therefore a selection instrument with ability of assessing different knowledge base or... 

Negative Bias Temperature Instability (NBTI) in CMOS devices is known as the major source of aging effect which is leading to performance and reliability degradation in modern processors. Instruction-cache (I-cache), which has a decisive role in performance and reliability of the processor, is one of the most prone modules to NBTI. Variations in duty cycle and long-time residency of data blocks in I-cache lines (stress condition) are the two major causes of NBTI acceleration. This paper proposes a novel I-cache management technique to minimize the aging effect in the I-cache SRAM cells. The proposed technique consists of a smart controller that monitors the cache lines behavior and... 

The presence of energy hubs and the advancement in smart grid technologies have motivated system planners to deploy intelligent multicarrier energy systems entitled "smart energy hub" (S.E. Hub). In this paper, we model S.E. Hub, and propose a modern energy management technique in electricity and natural gas networks based on integrated demand side management (IDSM). In conventional studies, energy consumption is optimized from the perspective of each individual user without considering the interactions with each other. Here, the interaction among S.E. Hubs in IDSM program is formulated as a noncooperative game. The existence and uniqueness of a pure strategy Nash equilibrium (NE) is proved.... 

Changes in business environment are leading firms to adopt a new production model called agile manufacturing. This term moves away from the traditional mass production paradigm and focuses on manufacturing highly customised products when customers require them. In this paper, we present an initial approach to agile organisation based on case studies in an Iranian industrial organisation. An agile organisation conceptual model has been drawn up, based on the conclusions of the case study. The study presented here is of an exploratory factor analysis and the conclusions are drawn through path analysis, propose possible routes for future research in the field of agile organisation. By the... 

This paper proposes an N-modular redundancy (NMR) technique with low energy-overhead for hard real-time multi-core systems. NMR is well-suited for multi-core platforms as they provide multiple processing units and low-overhead communication for voting. However, it can impose considerable energy overhead and hence its energy overhead must be controlled, which is the primary consideration of this paper. For this purpose the system operation can be divided into two phases: indispensable phase and on-demand phase. In the indispensable phase only half-plus-one copies for each task are executed. When no fault occurs during this phase, the results must be identical and hence the remaining copies... 

The rapid increase of information on the web makes it necessary to improve information management techniques. One of the most important techniques is clustering web data. In this paper, we propose a new 3-phase clustering method that finds dense units in a data set using density-based algorithms. The distances in the dense units are stored in order in structures such as a min heap. In the extraction stage, these distances are extracted one by one, and their effects on the clustering process are examined. Finally, in the combination stage, clustering is completed using improved versions of well-known single and average linkage methods. All steps of the methods are performed in O(n log n) time... 

Purpose: This research attempts to formulate an analytical model for the studying and assessment of necessary factors that have strong effects on the level of Iranian Technology Park competitiveness. The result of this model leads to increasing the effectiveness and efficiency of Technology Parks planning stage. Methodology/Approach: The main framework of this research is based on studying the projects and research, which in their methods use the Porter's diamond model or SWOT analytical method. On the other hand, this framework is customized for the future needs of Technology Parks and clarifies the kind of information that must be gathered. Finding: Identification of the core competencies... 

In this paper, to set R&D priorities at sector level, a developed method is proposed which is combined of scenario planning and critical technologies method and then applied for prioritizing R&D issues of membrane technology in National Iranian Gas Company (NIGC). In the first phase (through 3 steps), scope of NIGC is mapped using national documents and viewpoints of experts and managers. This map includes main process of gas processing and gas conversions. Then strategic goals of gas industry including gas exports, conversions, injection and internal use, are developed. Also Strategic Technology Units (STUs) are identified and twenty distinct membrane technologies including technologies of... 

According to International Technology Roadmap for Semiconductors (ITRS), before the end of this decade, we will be entering the era of a billion transistors on a single chip. The major threat toward the achievement of billion transistor on a chip is poor scalability of current interconnect infrastructure. With the advent of "Network on Chip (NoC)" various characters and methodologies of traditional networks were hardly considered on-chip. Failure, Power and Area are the major concepts that should be considered when migrating from traditional interconnection networks to NoCs. In this paper we study the effects of faulty links and nodes on power and performance of mesh based NoC, Also several...