• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.2
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• pp.61-70
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• 2008

Dynamic memory allocators are used for embedded systems to increase flexibility to manage unpredictable inputs and outputs. As embedded systems generally run continuously during their whole lifetime, fragmentation is one of important factors for designing the memory allocator. To minimize fragmentation, a budgeted memory allocator that has dedicated storage for predetermined objects is proposed. A budgeting method based on a mathematical analysis is also presented. Experimental results show that the size of the heap storage can be reduced by up to 49.5% by using the budgeted memory allocator instead of a state-of-the-art allocator. The reduced fragmentation compensates for the increased code size due to budgeted allocator when the heap storage is larger than 16KB.

• Korean Journal of Computational Design and Engineering
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• v.5 no.4
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• pp.373-379
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• 2000

This paper deals with the study of distributed design system and the implementation of JAVA based initial design system using CORBA/sup [1-3]/. In the state of initial design, designer should consider other information related to a design part. In this case, designer has a difficult problem to search and calculate distributed data. We propose a special connector named ‘Allocator’and implement an initial design system AIDS(Agent based Initial Design system). AIDS can help designer search and calculate the distributed information. In this study, JAVA and CORBA were chosen for handling network and distribute programming. AIDS focuses on the possibility of incremental concurrent design capability. AIDS is comported of Request-Agent, Calculator-Agent, View-Agent, Search-Agent, and ‘Allocator’. The proposed system can be used for designing initial design of a gripper in the web regardless of operating system.

• Journal of Digital Contents Society
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• v.9 no.1
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• pp.77-86
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• 2008

False sharing is a result of co-location of unrelated data in the same unit of memory coherency, and is one source of unnecessary overhead being of no help to keep the memory coherency in multiprocessor systems. Moreover, the damage caused by false sharing becomes large in proportion to the granularity of memory coherency. To reduce false sharing in page-based DSM systems, it is necessary to allocate unrelated data objects that have different access patterns into the separate shared pages. In this paper we propose sized and call-site tracing-based shared memory allocator, shortly SCSTallocator. SCSTallocator places each data object requested from the different call-sites into the separate shared pages, and at the same time places each data object that has different size into different shared pages. Consequently data objects that have the different call-site and different object size prohibited from being allocated to the same shared page. Our observations show that our SCSTallocator outperforms the existing dynamic shared memory allocators. By combining the two existing allocation technique, we can reduce a considerable amount of false sharing misses.

• Journal of KIISE:Software and Applications
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• v.29 no.12
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• pp.957-965
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• 2002

Garbage collection in the CLDC typically employs a stop-the-world GC algorithm which is performing a complete garbage collection when needed. This technique is unsuitable for the interactive Java embedded system because this can lead to long and unpredictable delays. In this paper, We present a garbage collection algorithm which reduces the average delay time and supports the interactive environment. Our garbage collector is composed of the allocator and the collector. The allocator determines the allocation position of free-list according to object size, and the collector uses an incremental mark-sweep algorithm. The garbage collector is called periodically by the thread scheduling policy and the allocator allocates the objects of marked state during collection cycle. Also, we introduce a color toggle mechanism that changes the meaning of the bit patterns at the end of the collection cycle. We compared the performance of our implementation with stop-the-world mark-sweep GC. The experimental results show that our algorithm reduces the average delay time and that it provides uniformly low response times.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.7
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• pp.708-712
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• 2008

Existing dynamic memory allocation schemes for general purpose operating system can not directly apply to the wireless sensor networks (WSNs). Because these schemes did not consider features of WSNs, they consume a lot of energy and waste the memory space caused by fragmentation. In this paper, we found features of WSNs applications and made the model which adapts these issues. Through this research, we suggest the slab allocator that reduces the execution time and the memory management space. Also, we evaluate the performance of our scheme by comparing to one of the previous systems.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10a
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• pp.265-266
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• 2007

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.4
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• pp.220-227
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• 2018

The cooperative game theory consists of a set of players and utility function that has positive values for a subset of players, called coalition, in the game. The purpose of cost allocation method is to allocate the relevant cost among game players in a fair and rational way. Therefore, cost allocation method based on cooperative game theory has been applied in many areas for fair and reasonable cost allocation. On the other hand, the desirable characteristics of the cost allocation method are Pareto optimality, rationality, and marginality. Pareto optimality means that costs are entirely paid by participating players. Rationality means that by joining the grand coalition, players do not pay more than they would if they chose to be part of any smaller coalition of players. Marginality means that players are charged at least enough to cover their marginal costs. If these characteristics are all met, the solution of cost allocation method exists in the core. In this study, proportional method is applied to EOQ inventory game and EPQ inventory game with shortage. Proportional method is a method that allocates costs proportionally to a certain allocator. This method has been applied to a variety of problems because of its convenience and simple calculations. However, depending on what the allocator is used for, the proportional method has a weakness that its solution may not exist in the core. Three allocators such as demand, marginal cost, and cost are considered. We prove that the solution of the proportional method to demand and the proportional method to marginal cost for EOQ game and EPQ game with shortage is in the core. The counterexample also shows that the solution of the proportional method to cost does not exist in the core.

• International Journal of Aerospace System Engineering
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• v.4 no.1
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• pp.1-8
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• 2017

This paper proposes the load distribution control allocation technique. The proposed method is designed by combining a conventional control allocation method with load distribution ability in order to reduce the stress acting on ailerons. By designing the weighting matrix as a function of the load distribution rule, the optimal deflection angles of each surface to satisfy both control goal and load distribution can be achieved. Moreover, rule based fault-tolerant control technique is also proposed. The rules are generated by considering both dominant control surfaces and the ratio of load distribution among surfaces. The performance of the proposed method is evaluated through numerical simulations.

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.125-143
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• 1997

As information is the critical resource of business, CIOs(chief information officers)' managerial roles become more important. CIOs work out the organization and information system strategies, introduce changes into organizations, communicate with chief executive officers and users, and take the responsibilities of the information system operation. The CIOs' managerial roles make affects on the information system performance and the organizational effectiveness. They are divided into six sub-roles; leader, liaison, entrepreneur, monitor, resource allocator and spokesman. The CIOs' influences on organizations are evaluated by information systems performance. User information satisfaction is one of the most valid information system evaluation criterions. User participation and user involvement are regarded as the antecedents of user satisfaction. This study investigates the effect of CIOs' managerial roles on user satisfaction, user participation, user involvement, CIOs' six managerial roles do not equally influence users. The results of this study have implications for the CIOs' managerial roles in organizations. As CIOs effectively perform managerial roles, user satisfaction is improved.

• Korean Management Science Review
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• v.25 no.2
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• pp.1-12
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• 2008

In the ultimatum game two players have to divide a certain amount of money between them. One player is the allocator and proposes a division of the money. The other is the recipient and can either accept or reject the proposed division. If the recipient accepts, the money is divided as proposed. If the recipient rejects, however, both players receive nothing. Purchase decisions could be classified on two basic factors (or dimensions) : involvement and think/feel in the FCB grid model. In this study we studied the influences of the two factors in purchase decisions on the choice of strategy (or propensity to fairness) in the ultimatum game. The empirical study showed that a decision maker chooses rational strategy more frequently when he (or she) is thinkful (or cognitive) in high involvement level.