• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3B
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• pp.487-492
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• 2000

The ABR(available bit rate) service has been developed to support data application over ATM(asynchronous Transfer mode) networks, and TCP is the most widely used transport layer protocol in existing data networks. Thus, the performance improvement of TCP over ABR is an issue of cardinal importance. In this paper, we propose algorithm of the adjustment of congestion window size utilizing RM(resource Management) cell information. The motivation is to use more reliable information in ER(explicit rate) field within RM cell to determine TCP window size. Simulations are performance using the suggested algorithm is improved, as compared to TCP-reno.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.127-141
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• 2014

A Vehicle Tracking System consists of GPS tracking device which fits into the vehicle and captures the GPS location information at regular intervals to a central GIS server, and GIS tracking server providing three major responsibilities: receiving data from the GPS tracking unit, securely storing it, and serving this information on demand of the user. GPS based tracking systems supporting a multi-session processing among RMA, RM, and RCP can make a quick response to various services including other vehicle information between RSU and OBU on demand of the user. In this paper we design RSU lower layers and RCP applications in OBU for a multisession processing simulation and test message processing transactions among RMA-RM and RM-RCP. Furthermore, we implement the additional functions of handling access commands simultaneously on multiple service resources which are appropriate for the experimental testing conditions. In order to make a multi-session processing test, it reads 30 resource data,0002/0001 ~ 0002/0030, in total and then occurs 30 session data transmissions simultaneously. We insert a sequence number field into a special header of dummy data as a corresponding response to check that the messages are received correctly. Thus, we find that GIS service system with a multi-session processing is able to provide additional 30 services in a same speed of screen presentation loading while identifying the number of session processing of Web GIS service, the number of OBU service, and the speed of screen presentation loading by comparing a single session and a multi-session of GIS service system.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.2
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• pp.15-24
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• 2016

GPS(Global Positioning System) location tracking is a method for taking the precise coordinates after the coordinates are obtained by a GPS receiver, and displaying them on the map. In this paper with WAVE(Wireless Access for Vehicular Environment) simulation, we show that various services such as vehicle tracking service, real-time road conditions service and logistics can go tracking service, control and operation services according to the vehicle position and the traveling direction by using the GPS position data. A vehicle tracking system using GPS is automatically able to manage multiple RCP when exchanging data between RMA and the RCP, and it provides rapid requests and responses. To verify that multiple sessions between RMA and RM, as well as multiple sessions between RMA and RCP are able to be implemented, we take RMA as a RCP application on an OBU, until the RMA is receiving data response from corresponding RM. As a result of this experiment, we show that the response speeds of single session between RMA and RM using 1, 2, 3, and 4 kbyte unit data are similar, 62.32ms, 62.65ms, 63.02ms, and 63.48ms, respectively. Likewise, those of 128 muliple sessions using 1, 2, 3, and 4 kbyte unit data are not much more time difference, 298.08ms, 302.21ms, 322.85ms, and 329.62ms, respectively.

• Journal of the Korea Society for Simulation
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• v.12 no.4
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• pp.51-59
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• 2003

Real-Time applications on Grid environment have several problems in terms of resource management addressed as follows; (1) dynamic resource allocation to provide QoS objectives, (2) heterogeneous resources that is different scale, or capacity in same unit, and (3) resource availability, and resource needs. This paper describes the techniques of resource manager (RM) handling above problems to support QoS of dynamic real-time applications on Grid. The contributions of this paper to solve problems are as follows: unification of dynamic resource requirements among heterogeneous hosts, control of resources in heterogeneous environments, and dynamic load balancing/sharing. Our heuristic allocation scheme works not only 257% better than random, 142% better than round robin, and 36.4% better than least load in QoS sensitivity, but also 38.6% better than random, 28.5% better than round robin, and 31.6% better than least load in QoS.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.5
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• pp.187-198
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• 2008

This paper develops a framework for efficient resource management within the grid service environment. Resource management is the core element of the grid service; therefore, GridRMF(Grid Resource Management Framework) is modeled and developed in order to respond to such variable characteristics of resources as accordingly as possible. GridRMF uses the participation level of grid resource as a basis of its hierarchical management. This hierarchical management divides managing domains into two parts: VMS(Virtual Organization Management System) for virtual organization management and RMS(Resource Management System) for metadata management. VMS mediates resources according to optimal virtual organization selection mechanism, and responds to malfunctions of the virtual organization by LRM(Local Resource Manager) automatic recovery mechanism. RMS, on the other hand, responds to load balance and fault by applying resource status monitoring information into adaptive performance-based task allocation algorithm.

• Journal of Family Resource Management and Policy Review
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• v.15 no.1
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• pp.177-197
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• 2011

This study was designed to develop the evaluation scale for health-grade of families. For this goal the related references and the programs of Healthy-Families-Center were analyzed. In the context with the goals and objects of programs in Healthy-Families-Center the index for the evaluation the health-grade of families was deducted. And the concrete items of health-grade of families in 3 parts(R: relation, M: management, E: environment) was discussed. In order to verify the validity and significance of the scale the survey for 200 samples was performed and the data from 191 samples was statistically analyzed. We suggested the application methods of this evaluation scale for health-grade of families. So the 8 types of families were came out: RME, RMe, RmE, rME, Rme, rMe, rmE, rme. Using this type of families the consulting and counselling for the enhancement of health-grade can be developed. We reached the conclusion that this evaluation scale has to be continuously developed and eleborated because the health-grade of families is one of the most important index for the effect of programs of Healthy Families Center.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.1
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• pp.79-86
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• 2013

In this paper which it is relating to the DSRC system based road side equipment, we propose the protocol stack architecture of road side equipment and the process structure of the main RM, L7 and LLC layers which is road side equipment device as well. And also we design the signal flow and data-transfer process as well between road side equipment and on board equipment to describe the installation process between road side equipment and von board equipment based on DSRC system. Thus, it is possible to provide various application services between intelligent transportation systems of road side equipment and local server, as well as it enables the local server managing the memorys of on board equipment which entry in service area thru the road side equipment.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.1
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• pp.39-43
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• 2007

In high speed communication networks, the determination of a transmission rate is critical for the stability of a closed-loop network system with the congestion control scheme. In ATM networks, the available bit rate (ABR) service is based on a feedback mechanism, i.e., the network status is transferred to the ABR source by a resource management (RM) cell. RM cells contain the traffic information of the downstream nodes for the traffic rate control. However, the traffic status of the downstream nodes can not be directly transferred to the source node in the IP based networks. In this paper, a new rate-based congestion control scheme using an exponential weighted moving average algorithm is proposed to build an efficient feedback control law for congestion avoidance in high speed communication networks. The proposed congestion control scheme assures the stability of switch buffers and higher link utilization of the network. Moreover, we note that the proposed congestion scheme can flexibly work along with the increasing number of input sources in the network, which results in an improved scalability.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.61-73
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• 2014

An automatic vehicle location tracing system is to build GIS server and on transmission for providing service in various ways by collecting a GPS location information from each vehicle. It is to save GPS data from OBU built-in on the vehicle and transmit the GPS data using the RSU on the roadside and WAVE communication technology. The collected data from the RSU is transmitted to the GIS server and stored in DB(database) and based on the GPS data that was collected from the each vehicle the system is to provide user service to suit the applications so it is to provide various services between RSU and OBU. In this paper, by implementing a multi-session process between the RM and the RMA a variety of services between RSU and OBU are provided. In addition, the system is designed and implemented using GPS to provide a variety of services, for the services provided from each RMA by configuring them as an independent session so it enables a variety of services implemented from one of RSU. With the result of the comparative analysis on the multi-session processing and single-session processing it shows that the differenes of them are minor in repect of the data loss rate and the data transfer rate but various services can be provided.

• Journal of Distribution Science
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• v.18 no.11
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• pp.91-103
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• 2020

The recent Covid-19 outbreak has caused severe disruption of the global supply chain, which tests firms' ability to survive and build resilience. The concept of adaptive supply chain management (A-SCM) has never been tested against a severe supply chain disruption, such as a pandemic. Purpose: The aim of this study is to examine how firms in Indonesia develop resilience through the implementation of components of adaptive supply chain management, namely risk management, resource reconfiguration and supply chain flexibility, in order to survive severe supply chain disruption. Research design, data and methodology: A qualitative method and PLS-SEM were used to analyze 120 data collected from Indonesian manufacturing firms in various industries. Results: The findings show that risk management, resource reconfiguration, and supply chain flexibility are important components that make up A-SCM. However, only risk management contributes to help build firm resilience in the presence of severe supply chain disruption. Conclusions: The components of A-SCM have been empirically tested. The implication is that managers should carefully use RM to prepare firms for different scenarios to develop contingency strategies. This research contributes to the supply chain management body of knowledge in the context of pandemic-level disruption and broadens the dynamic capabilities perspective.