• Journal of Internet Computing and Services
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• v.1 no.2
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• pp.11-18
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• 2000

In this paper we present a new extensible model based upon the concept of subtransactions in real-time transaction systems. The nested transaction model originally proposed by J. Moss is extended for real-time uniprocessor transaction systems by adding explicit timing constraints. Based upon the model, an integrated concurrency control and scheduling algorithm is developed, that not only guarantees timing constraints of a set of real-time transactions but also maintains consistency of the database. The algorithm is based on the priority ceiling protocol of Sha et al. We prove that the Real-Time Nested Priority Ceiling Protocol prevents unbounded blocking and deadlock, and maintains the serializability of a set of real-time transactions. We use the upper bound on the duration that a transaction can be blocked to show that it is possible to analyze the schedulability of a transaction set using rate-monotonic priority assignment. This work is viewed as a step toward multiprocessor and distributed real-time nested transaction systems. Also, it is possible to be extended to include the real-time multimedia transactions in the emerging web-based database application areas.

• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.2158-2170
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• 1999

It has been required more reliable communication on processes and improvement of system performance as distributed systems using multicast protocol became widespread. In distributed environment maintaining data consistency through asynchronous execution of processes and coordinating the activities of them would occurs. This paper proposes a total ordering algorithm, TORMP, in order to resolve these problems. TORMP takes advantage of multicast protocol and uses an effective token passing method. It reduces a process delaying time before transmitting its message by multicasting a token simultaneously to every process that initiates the request of the message. Moreover, the processes receiving the token start multicasting the message at the same time, which causes to cut down the overall transmission dely. In case that one process sends a message, TORMP hardly uses the procedure of controlling for ordering. It gives fairly the right of sending messages to all processes in a group with utilizing vector clock. In TORMP, unlike other algorithms, the number of packets generated during ordering process does not depend on the number of processes.

• The Transactions of the Korea Information Processing Society
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• v.7 no.1
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• pp.156-165
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• 2000

This paper proposes an integrated system for interworking different network management protocols. The interworking system between SNMP(Simple Network Management Protocol) and CMIP(Common Management Information Protocol) has been designed. We defined new managed object architecture using MOVI(Managed Object View Interface) concept and implemented an extended GDMO(EGDMO) compiler. An access mechanism for consistency control and atomic action on the sharing resources has been defined. Thus, even if a new management protocol would be introduced, new gateway system need not to be redesigned. It can be achieved with minimum modification of the view interface of managed objects. As a managed object can support various view interfaces, several network management protocols can directly access it. This approach, therefore, provides some benefits. For instance, manager can access managed objects without additional functions and tools. Ti, also, could be achieved interworking between SNMP and CMIP with minimum modification on the view interface of the managed objects defined previously. It is able to interwork more complicated network management protocols and to increase usefulness of SNMP and CMIP.

• Journal of the Korean Society for Library and Information Science
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• v.58 no.2
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• pp.225-249
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• 2024

The purpose of this study is to develop an evaluation tool for map-based data visualization platforms and to conduct heuristic usability evaluations on existing platforms representing inter-regional information. We compared and analyzed the usability evaluation criteria of map-based platforms from the previous studies along with Nielsen's (1994) 10 usability evaluation principles. We proposed nine evaluation criteria, including (1) visibility, (2) representation of the real world, (3) consistency and standards, (4) user control and friendliness, (5) flexibility, (6) design, (7) compatibility, (8) error prevention and handling, and (9) help provision and documentation. Additionally, to confirm the effectiveness of the proposed criteria, four experts was invited to evaluate five domestic and international map-based data visualization platforms. As a result, the experts were able to rank the usability of the five platforms using the proposed map-based data visualization usability evaluation criteria, which included quantified scores and subjective opinions. The results of this study are expected to serve as foundational material for the future development and evaluation of map-based visualization platforms.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.1
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• pp.39-67
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• 1987

The purpose of this thesis is to suggest objective basic data for the environmental design through the quantitative analysis of the visual quality included in the physical environment of forest landscape. For this, landscape values of forest landscape have been evaluated by using the Iverson method, the images structure of forest landscape's main utilizing space have been analysed by the factor analysis algorithm, degree of visual preferences have been pleasured mainly by questionnaries and SBE method, and finally these thesis can be summarized as fallow LCP with high values of Iverson factors I and IV yield high landscape value. Specifically, Iverson factor IV has been found to play the dominant. For all experimental points, significant seasonal variations in S.D. scale values have been observed. In natural parks, where artificial structures are complementary to the natural landscape, main factors of image are S.D. scales such as the visual sequence, the formal simplicity of structures, the emphasis, the unification of heterogeneous factors and the assimilation. Factors covering the spatial image of natural parks have been found to be the overall evaluation, the individual characteristics, the tidiness, the potentiality, the dignity, the intimacy and the space volume. For all seasons, factors such as the individual characteristics, the dignity, the tidiness, the potentiality, yield high factor scores. As for factors determining the degree of visual preference, variables such as the summit, the skyline, rocks, the water and the degree of natural destruction by artificial structures yield high values for all seasons.

• Proceedings of the ESK Conference
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• 1993.10a
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• pp.46-55
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• 1993

조종사가 수행하는 조종 업무는 여러 정보를 동시에 지각하여 처리하여 야 하는 복잡한 작업으로 구성되어 있어, 조종사에게는 고도의 인간성능이 요구되고 있다. 또한 조종기술을 습득하기 위해서는 많은 훈련시간과 비용 이 소요되며, 조종사의 실수는 치명적인 사고를 초래한다. 따라서 조기에 비행 부적격자를 판별하고, 미흡한 조종 적성을 함양시킬 수 있는 교육 . 훈련 프로그램을 조종 후보생에게 적용시키는 분석적 조종적성 진단 체계 개발은 조 종사의 도태율 감소, 효율적인 비행훈련, 비행 안전사고 감소 등의 측면에서 절실하게 요구되고 있다. 본 연구에서는 조종 업무 수행시 요구되는 여러 인간 기능의 중요도 차이를 조종 적성 평가 체제에 적용하기 위해서, 각 적성 검사 항목들의 상대적 중요도를 분석하고 이의 타당성을 평가하였다. 적성검사 항목의 상대적 중요도 분석은 조종적성검사 계층구조의 각 수준별 쌍체 비교 평가와 AHP(Analytic Hierarchy Process) 분석에 의한 상대적 중요도 산출 및 평가, 그리고 일관성 지수(Consistency Index)에 의한 분석 결과의 조정을 통해 이루어 졌다. 적성검사 항목의 쌍체 비교 평가는 심리기능검사, 비행자질 검사 등 총 29개 적성검사 항목에 대해 검사를 받았고 또한 초등비행 훈련과정을 수료한 조종 학생들에 의해 이루어 졌다. 상대적 중요도를 분석한 결과 심리기능 검사(W=0.30)가 다른 검사에 비하여 조종적성 평가에 중요한 검사로 나타났으며, 세부 항목으로는 주의 분배력(W=0.13), 추적능력(0.06) 등이 상대적으로 중요한 검사 항목으로 나타났다. 또한 상대적 중요도 결과를 적용한 적성검사 성적이 적용하지 않은 적성검사 성적에 비해 비행성적에 대한 예측 능력이 좋은 것으로 평가되었다.al age)가 있다는 것을 의미하는 것이다. 한편, 생산현장에서는 자동화, 기계화가 진보되어 육체적인 노동이 경감된 결과, 중고령자라도 할 수 있는 작업이 많아지고 있다. 또, VDT (Visual Dislay Terminal) 작업과 같은 정보처리 작업의 수요가 증가하여 그 인재의 부족이 지적되고 있다. 따라서 중고령자의 기능을 조사하여 어떠한 작업에 적합한가를 판단하는 것이 중요한 과제로 되었다. 그러나 노동에는 많은 기능이 관여 하고, 그 내용에 따라서 요구되는 기능이 서로 다르기 때문에 노동적응능력의 기본적인 기능으로 보여지는 것에 좁혀서 작업능력의 연령증가 변화에 대하여다원적 평가를 하는 것이 실제적이라고 할 수 있다. 따라서 본 연구에서는 인간이 가지고 있는 다수의 기능중에서 수지교 치성과 연령증가와의 관계를 조사한다. 만약 연령증가 만으로 수지교치성을 평가 할 수 없는 경우에는 어떠한 요인이 수지기민성의 변화에 영향을 미치는가를 검토한다.t list)에서 자동적으로 사건들의 순서가 결정되도록 확장하였으며, 설비 제어방식에 있어서도 FIFO, LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과

• Journal of the Korea Society of Computer and Information
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• v.18 no.6
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• pp.63-70
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• 2013

In accordance with the advancement of IT, application systems with various and complex functions are being required. Such application systems are typically built based on database in order to manage data efficiently. But most object-oriented analysis design methodologies for developing web application systems have not been providing interconnections with the database. Since the requirements regarding the security issues increased, the importance of security has become emphasized. However, since the security is usually considered at the last step of development, it is difficult to apply the security during the whole process of system development, from the requirement analysis to implementation. Therefore, this paper suggests an object-oriented analysis and design methodology for secure database design from the requirement analysis to implementation. This object-oriented analysis and design methodology for secure database design offers correlations with database that most existing object-oriented analysis and design methodologies could not provide. It also uses UMLsec, the modeling language, to apply security into database design. In addition, in order to implement security, RBAC (Role Based Access Control) of relational database is used.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.3
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• pp.322-331
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• 2003

As the complexity of a 3D game is increased by various factors of the game scenario, it has a problem for controlling the interrelation of the game objects. Therefore, a game system has a necessity of the coordination of the responses of the game objects. Also, it is necessary to control the behaviors of animations of the game objects in terms of the game scenario. To produce realistic game simulations, a system has to include a structure for designing the interactions among the game objects. This paper presents a method that designs the dynamic control mechanism for the interaction of the game objects in the game scenario. For the method, we suggest a game agent system as a framework that is based on intelligent agents who can make decisions using specific rules. Game agent systems are used in order to manage environment data, to simulate the game objects, to control interactions among game objects, and to support visual authoring interface that ran define a various interrelations of the game objects. These techniques can process the autonomy level of the game objects and the associated collision avoidance method, etc. Also, it is possible to make the coherent decision-making ability of the game objects about a change of the scene. In this paper, the rule-based behavior control was designed to guide the simulation of the game objects. The rules are pre-defined by the user using visual interface for designing their interaction. The Agent State Decision Network, which is composed of the visual elements, is able to pass the information and infers the current state of the game objects. All of such methods can monitor and check a variation of motion state between game objects in real time. Finally, we present a validation of the control method together with a simple case-study example. In this paper, we design and implement the supervised classification systems for high resolution satellite images. The systems support various interfaces and statistical data of training samples so that we can select the most effective training data. In addition, the efficient extension of new classification algorithms and satellite image formats are applied easily through the modularized systems. The classifiers are considered the characteristics of spectral bands from the selected training data. They provide various supervised classification algorithms which include Parallelepiped, Minimum distance, Mahalanobis distance, Maximum likelihood and Fuzzy theory. We used IKONOS images for the input and verified the systems for the classification of high resolution satellite images.

• The Transactions of the Korea Information Processing Society
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• v.4 no.4
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• pp.1089-1099
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• 1997

The Q.2931 protocol describes the point-to-point basic call/connection controal at user-network interface(UNI) and is the core part of the Signalling Capability Set 2 step 1 (CS 2.1) of B-ISDN in ITU-T.The adtivities on CS 2.1 is also under study in korea and categorized as the first stage.The Q.2931 protocol should be applied to various devices with cinsistency especially among network divices.But , It is hard to inmplement this protocol into a de-vice with cinsistency because this protocol has so many optious.Especially, the divice that charges for network foles must takes into account of various considerations.In this paper, we focused our study on the optional in-formantion elments of the Q.2931, and would like ot redefine the chracteristics of optional information elements for the point of the national boundary and proposed some common actions to the devies with network role.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.1
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• pp.35-41
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• 2002

It is extremely important to minimize network access time in constructing a high-performance PC cluster system For an SCI based PC cluster it is possilbe to reduce the network access time by maintaining network cache in each cluster node, This paper presents a CC-NUMA card that utilizes network cache for SCI based PC clustering The CC-NUMA card is directly plugged into the PCI solot of each node, and contains shared memory network cache, and interconnection modules. The network cache is maintained for the shared memory on the PCI bus of cluster nodes. The coherency mechanism between the network cache and the shared memory is based on the IEEE SCI standard. A CC-NUMA prototype card is developed to evaluate the performance of the system. According to the experiments. the cluster system with the CC-NUMA card showed considerable improvements compared with an SCI based clustser without network cache.