• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3399-3406
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• 2015

NRD(Network RamDisk) is a scheme which allows a system to use the memory of the remote systems just as his own block device via networking. Basically, it consists of a client requesting an NRD access and server providing the NRD. In this paper, we describe the design, implementation and experiment of the block device driver for accessing the NRD in the Linux kernel(2.6) level. First of all, we have analyzed the flow of processing the requests for accessing the block devices in the traditional Linux kernel and figured out the additional functions required for supporting the NRD. Then we have designed and implemented the device diver of NRD client and NRD server for providing these functions. Finally, we have established a NRD server system, and reviewed its functional feasibility by experimenting the requests of NRD access through the NRD device driver implemented on a NRD client.

• The Transactions of the Korea Information Processing Society
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• v.6 no.7
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• pp.1777-1788
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• 1999

The portability of Java language makes it possible to use heterogeneous computers without re-compiling of application programs. Java applet can also be transported to other computers via Web browser. In this research, a Cooperative Web Computing Environment(CWCE) that uses idle computers on the Intranet for cooperative parallel computing work is suggested. The CWCE allows to use more than a manager computer that sends applets and manages communication between other computers. The number of manager computers can be determined according to the characteristics of computing environment and any chosen application program. It can reduce the amount of communication overhead for the application programs especially with synchronized communication. For the CWCE, a decision function to determine the managing level is provided. The CWCE turns out to be useful computing environment for the applications with less computation request ratio and multi-managing can help to reduce the communication overhead especially for the applications with a high ratio of synchronization purpose communications.

• Journal of Internet Computing and Services
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• v.11 no.1
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• pp.153-165
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• 2010

In this paper, we proposed a Proactive Application Service Engine (PASE) supporting tailor-made distributed application services based on the Distributed Object Group Framework (DOGF) efficiently managing distributed objects, in the viewpoint of distributed application, composed application on network. The PASE consists of 3 layers which are the physical layer, the middleware layer, and the application layer. With the supporting services of the PASE, the grouping service manages the data gathered from H/W devices and the object's properties for application by user's request as a group. And the security service manages the access of gathered data and the object according to user's right. The data filtering service executes the filtering function to provide application with gathered data. The statistics service analysis past data. The diagnostic service diagnoses a present condition by using the gathered data. And the prediction service predicts a future's status based on the statistics service and the diagnostic service. For verifying the executability of the PASE's services, we applied to a greenhouse automatic control application in ubiquitous agriculture field.

• Journal of the Korean Society for Library and Information Science
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• v.8
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• pp.73-101
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• 1981

Retrieval effectiveness is the principal criterion for measuring the performance of an information retrieval system. The effectiveness of a retrieval system depends primarily on the extent to which it can retrieve wanted documents without retrieving unwanted ones. So, ultimately, effectiveness is a function of the relevant and nonrelevant documents retrieved. Consequently, 'relevance' of information to the user's request has become one of the most fundamental concept encountered in the theory of information retrieval. Although there is at present no consensus as to how this notion should be defined, relevance has been widely used as a meaningful quantity and an adequate criterion for measures of the evaluation of retrieval effectiveness. The recall and precision among various parameters based on the 'two-by-two' table (or, contingency table) were major considerations in this paper, because it is assumed that recall and precision are sufficient for the measurement of effectiveness. Accordingly, different concepts of 'relevance' and 'pertinence' of documents to user requests and their proper usages were investigated even though the two terms have unfortunately been used rather loosely in the literature. In addition, a number of variables affecting the recall and precision values were discussed. Some conclusions derived from this study are as follows: Any notion of retrieval effectiveness is based on 'relevance' which itself is extremely difficult to define. Recall and precision are valuable concepts in the study of any information retrieval system. They are, however, not the only criteria by which a system may be judged. The recall-precision curve represents the average performance of any given system, and this may vary quite considerably in particular situations. Therefore, it is possible to some extent to vary the indexing policy, the indexing policy, the indexing language, or the search methodology to improve the performance of the system in terms of recall and precision. The 'inverse relationship' between average recall and precision could be accepted as the 'fundamental law of retrieval', and it should certainly be used as an aid to evaluation. Finally, there is a limit to the performance(in terms of effectiveness) achievable by an information retrieval system. That is : "Perfect retrieval is impossible."

• Journal of Advanced Navigation Technology
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• v.17 no.5
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• pp.560-567
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• 2013

In this paper, it is proposed the fault detection method of the ASIC, without the Test Requirement Document(TRD), extracting internal logic circuit and analyzed the function of the ASIC using the multipurpose development program and simulation. If there don't have the TRD, it is impossible to analyze the operation of the circuit and find out the fault detection in any chip. Therefore, we make the TRD based on the analyzed logic data of the ASIC, and diagnose of the ASIC circuit at the gate level through the signal control of I/O pins using the Dynamic Pattern signal. According to the experimental results of the proposed method, we is confirmed the good performance of the fault detection capabilities which applied to the non-memory circuit.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.3
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• pp.89-94
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• 2019

K1A1 tank commander's primary thermal sight is a device that enables tank commanders to detect, identify, aim and track the target by observing targets in all directions during day, night and in situations of smokescreen and fog through $360^{\circ}$ rotation independent from the gunner's primary thermal sight and stabilizing the line of sight even under the vibrations occurring when the tank is standstill and moving. The main function of this device is to detect and process visible and thermal images and deliver the final images to the tank commander. One of the core parts to that end is the observation window (daytime/thermal image window). This core part is mounted at the entrance of the optical path for observing the target and plays the role of making visible light during the daytime and infrared light during the night pass through the target and transmitting the resultant images to the internal optical system of the tank commander's primary thermal sight. Such core parts have been selected as depot maintenance items so that they are replaced by new parts instead of being recycled when they are subjected to maintenance in most cases. That is, the military budget is wasted because such parts are replaced by new parts despite that they can be recycled for maintenance. Therefore, this study proposed a mounting tool for polishing and coating observation windows (daytime and thermal image window) using planar polishing equipment and DLC (Diamond-Like Carbon) coating equipment. In addition, this study presented an amendment (proposal) of the Depot Maintenance Work Request (DMWR) already published to verify the performance of recycled products including the establishment of inspection standards for recycling processes.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.2
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• pp.105-115
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• 2009

At the most recent, IPTV service is increasing, which isa communicative broadcasting fusion service that provides various multimedia contents interactively followed by user's request through super high-speed internet. For IPTV user service with high mobility, IPTV user's enrollment is essential. However, IPTV service provided to mobile users can't provide the certification of mobile user securely. This paper proposes light user certification protocol which can certificate mobile users by attaching RFID to IPTV STB for secure awareness of mobile users who get IPTV service. The proposed protocol prevent reply attack and man-in-the-middle attack from happening oftenin a wireless section by transmitting the result value hashed by hash function with both its' ID and random number received from tag after tag transmits random number which generated randomly in the process of certification of mobile user to IPTV STB.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.6
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• pp.115-125
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• 2001

Authentication and access control are essential requirements for the information security of distributed environment. Delegation is process whereby an initiator principal in a distributed environment authorizes another principal to carry out some functions on behalf of the former. Delegation of access rights also increases the availability of services offer safety in distributed environments. A delegation easily provides principal to grant privileges in the single domain with Role-Based Access Control(RBAC). But in the multi-domain, initiators who request delegation may require to limit the access right of their delegates with restrictions that are called delegate restriction to protect the abuse of privilege. In this paper, we propose the delegation view as function of delegation restrictions. Proposed delegation view model not only prevent over-exposure of documents from granting multiple step delegation to document sharing in multi-domain with RBAC infrastructure but also reduce overload of security administrator and communication.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.3
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• pp.929-946
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• 2022

Free viewpoint video (FVV) service is an immersive media service that allows a user to watch it from a desired location or viewpoint. It is composed of various forms according to the direction of the viewpoint of the provided video, and includes zoom in/out in the service. As consumers' demand for active watching is increasing, the importance of FVV services is expected to grow gradually. However, additional considerations are needed to seamlessly stream FVV service. FVV includes a plurality of videos, video changes may occur frequently due to movement of the viewpoint. Frequent occurrence of video switching or re-request another video can cause service delay and it also can lower user's quality of service (QoS). In this case, we assumed that if a video showing an object that the user wants to watch is selected and provided, it is highly likely to meet the needs of the viewer. In particular, it is important to provide an object-oriented FVV service when zooming in. When video zooming in in the usual way, it cannot be guaranteed to zoom in around the object. Zoom function does not consider about video viewing. It only considers the viewing screen size and it crop the video view as fixed screen location. To solve this problem, we propose a zoom in/out method of object-centered dynamic adaptive streaming of FVV in this paper. Through the method proposed in this paper, users can enjoy the optimal video service because they are provided with the desired object-based video.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.2
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• pp.17-26
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• 2023

Purpose: The purpose of this study is to identify policy implications for the construction of public health facilities in the field of international cooperation, by examining the case of establishing a health care delivery system using a public health center in a rural area of Paraguay. Methods: Firstly, to map the capacity of the 20 public health centers that were studied, we used the WHO Capacity Mapping tool to select and analyze relevant items. Secondly, to assess the utilization of public health centers, we conducted a direct visit survey and analyzed the results using the M-survey tool. Results: The floor plan of each public health center, the structure of the health center, the size of the population served by each health center, the number of monthly visitors, medical human resources, and the budget were classified by health center for comparative analysis. In addition, by utilizing the M-survey tool, we analyzed the general characteristics of the respondents, their perceptions of the purpose and accessibility of public health centers, their satisfaction with using public health centers, and the level of demand for public health centers to play a role in promoting community health. Implications: The results of this study suggest that access to public health facilities for residents in the research area was improved. By classifying public health centers into two types, these centers can perform the functions and roles of primary health facilities. A patient request and evacuation system was established in the research area. Finally, a network, such as a social prescribing program, is needed so that public health centers can function as a "setting" for community members to live together.