• Korean System Dynamics Review
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• v.9 no.1
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• pp.199-218
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• 2008

Empirical studies have shown that government and human service nonprofit organizations have maintained active partnerships to deliver human services for the past several decades. However, the previous researches on resource dependent government-nonprofit service delivery have revealed serious methodological limitations to adequately demonstrate the dynamic relationship between both sectors over time. Since the dynamics underlying the government-nonprofit service delivery is a complex process, in which multiple factors dynamically interact over time, the assumptions of system dynamics can help improve these methodological drawbacks. This study aims to explore methodological issues and weaknesses observed in empirical studies on resource dependent government-nonprofit service delivery in the United States, and further attempts to provide insights on future research toward a dynamic approach, bringing the assumptions of system dynamics to the challenges of the previous researches.

• The Journal of the Korea Contents Association
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• v.10 no.3
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• pp.80-91
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• 2010

Due to the convergence of broadcasting and communications, IPTV services are spotlighted as the that next-generation multimedia services. IPTV services should have functionality such as unlimited channel capacity, extension of media, QoS awareness and are required increasing traffic and quality control technology to adapt the attributes of IPTV service. Consequently, flow based quality control techniques are needed. Therefore, many studies for providing Internet QoS are performed at IETF (Internet Engineering Task Force). As the buffer management mechanism among IP QoS methods, active queue management method such as RED(Random Early Detection) and modified RED algorithms have proposed. However, these algorithms have difficulties to satisfy the requirements of various Internet user QoS. Therefore, in this paper we propose the Flow based AQM(Active Queue Management) algorithm for the multimedia services that request various QoS requirements. The proposed algorithm can converge the packet loss ratio to the target packet loss ratio of required QoS requirements. And we present a performance evaluation by the simulations using the ns-2.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12B
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• pp.2283-2291
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• 1999

Most of collaborative applications use the Server-Client paradigm where all requests of clients will be delivered first to server and that server distributes again the requests to the rest of clients. This server-oriented operation and data transmission mechanism always presents end-to-end communications between the server and clients that can notably decrease the overall performance of applications. In this paper, we propose a new design approach to inhibit the inefficiency of applications using active networking concepts. We propose the ASM service that offers an application-specific in-network multicast functions, the AMTC service and its tree algorithm that builds anon-core based shared tree for multicast. These proposed services locate in active nodes performing its services as part of the overall system to improve the performance of collaborative applications.

• The Korean Journal of Health Service Management
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• v.9 no.1
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• pp.123-131
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• 2015

The purpose of this study was to investigate the relationships among self-leadership, stress coping skills, and college life adjustment in nursing students. The data were collected using a self-reported questionnaire from November 4 to November 22. The subjects of the study were 335 nursing students in 1 nursing college located in K city. The data were analyzed by descriptive statistics, t-test, ANOVA, Scheffe's test, and multiple regression test using the SPSS Win. 18.0 program. The results were as follows: the mean score of self-leadership was 3.38, the mean score of stress coping skills was 3.45, and the mean score of college life adjustment was 3.35. There was a significant difference in college life adjustment according to motivation of entrance. Goal-setting, self-reward, and constructive ideas about the self-leadership and active stress coping skills were influencing factors of college life adjustment. In conclusion, it is necessary to increase the level of self leadership and active stress coping skills in nursing students. The results of this study suggest that it is necessary to develop diverse educational programs that can increase self-leadership and active coping skills.

• Journal of the Korea Society for Simulation
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• v.12 no.3
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• pp.55-68
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• 2003

As mobile IP has been suggested only to support mobility of mobile station(MS) by which it dose nothing but guarantee MS's new connection to the network, it is for nothing in Quality of Service(QoS) after handoff of MS. QoS is very important factor in mobile IP network to provide multimedia applications and real-time services in mobile environment, and it is closely related to handoff delay Therefore as a main issue in mobile IP research area, handoff delay problem is actively studied to guarantee and promote QoS. In this paper, in order to resolve such a problem, we suggest Simple Network Management Network(SNMP) information-based routing that adds keyword management method to information-based routing in active network, and then propose QoS controlled handoff by SNMP information-based routing. After setting up routing convergence time, modeling of suggested method and existing handoff method is followed in order to evaluate the simulations that are carried out with NS-2. The result of simulation show the improvement of handoff delay, and consequently it turns off the QoS has been improved considerably.

• Korean Journal of Childcare and Education
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• v.19 no.3
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• pp.41-57
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• 2023

Objective: The objective of this study is to classify the personality types of early childhood teachers and examine the variations in teacher self-efficacy and play support based on these personality types. Methods: The subjects of this study consisted of 302 early childhood teachers responsible for children aged 3 to 5 years old. The collected data were analyzed using cluster analysis and analysis of covariance. Results: Early childhood teachers were categorized into four types: the "sensitive group" (29%), the "conservative group" (10%), the "passive group" (28%), and the "active group" (34%). Significant differences in mean scores were observed for teacher self-efficacy and play support across these personality types. Notably, the active group demonstrated the highest levels of both teacher self-efficacy and play support. Consequently, the active group emerged as the most effective and functional personality type among early childhood teachers. Conclusion/Implications: This study emphasized the significance of early childhood teachers' personality types in their teaching practices, underscoring the importance of developing in-service and pre-service teacher education programs that take into account these personality types.

• Korea Science and Art Forum
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• v.19
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• pp.259-267
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• 2015

Product-Service Systems (PSS) has drawn significant attention since it can effectively address diverse values of consumers by integrating products and services. PSS has been defined as a system of products, services, supporting networks and infrastructure that is designed to satisfy customer needs and to generate values. Manufacturing companies can accomplish business innovation by devising new service elements and providing PSSs starting from their products. Such new efforts are called manufacturing servitization. With analysis of the company's business contexts, diverse strategies could be set for servitization. Services could be developed so that their product functions can be supported. On the other hand, new services could be devised to drive active emotional values of their customers in a broadly related manner with their products. In this way, different servitization strategies in service space could be employed. In this paper, the product-service integration spaces for comparison of product-service systems in manufacturing servitization is briefly sketched. Various issue spaces, termed dimensions, would be used including service space, customer space, value space and business model space. Diverse PSS cases, including well-known PSSs and brand new PSSs, will be classified and compared to demonstrate the product-service integration spaces.

• Journal of the Korea Society of Computer and Information
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• v.16 no.9
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• pp.131-143
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• 2011

Previous alerting service based on LBS was caused severe overload problem of server by using the method to confirm the location of each moving object on server. In this paper, by loading an App on smart moving object, we proposed a novel algorithm named ADAS(Active Disaster Alert Service) for accessing to the server site with oneself location information as needed and implemented the disaster alerting service system with visualization for user. In the proposed method, running App access to the server periodically with the present location coordinate gained from GPS module or network module and the ID of moving object. Then, the server compare the present location coordinate of moving object and the coordinates of disasters registered in DIDB and transmit the n NDIs existed in near distance orderly from the coordinate of present moving object to the client. The App compares the coordinate of present location for moving object and the coordinates of NDI is transmitted from server by real time and executes the service with classifying levels of alert into three steps such as danger, carefulness and safety. And new NDIs are gained by accessing DIDB on Server periodically during running App. Therefore, this will be become a novel method for reducing fundamentally the server overload problem in comparison with previous alerting service that the career of moving object is managed on server.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.149-157
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• 2019

Recent research has been actively carried out on systems that want to optimize resource utilization by analyzing the intended behavior and pattern of behavior of objects (users, consumers). A service system that applies information about an object's location or behavior must include a location trigger processing system for tracking an object's real-time location. In this paper, we analyze design problems for the implementation of a context-awareness based location trigger system, and present system models based on analysis details. For this purpose, this paper introduces the concept of location trigger for intelligent location tracking techniques about moving situations of objects, and suggests a mobile agent system with active rules that can perform monitoring and appropriate actions based on sensing information and location context information, and uses them to design and implement the location trigger system for context-awareness based location services. The proposed system is verified by implementing location trigger processing scenarios and trigger service and action service protocols. In addition, through experiments on mobile agents with active rules, it is suggested that the proposed system can optimize the role and function of the application system by using rules appropriate to the service characteristics and that it is scalable and effective for location-based service systems. This paper is a preliminary study for the establishment of an optimization system for utilizing resources (equipment, power, manpower, etc.) through the active characteristics of systems such as real-time remote autonomous control and exception handling over consumption patterns and behavior changes of power users. The proposed system can be used in system configurations that induce optimization of resource utilization through intelligent warning and action based on location of objects, and can be effectively applied to the development of various location service systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.11
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• pp.1050-1057
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• 2012

Super Wi-Fi is a newly emerging wireless Internet technology, which constitutes Wi-Fi networks using TV white space. A key technical challenge in the Super Wi-Fi applications is how to provide a seamless Internet service even when a Super WiFi user should give up the channel in use to the active incumbent user which is activated in the same service area, preventing from the service continuity in Super Wi-Fi. In this paper, we propose a channel handover method to support service continuity of Super Wi-Fi, in which an AP selects a new operational channel and provides the channel information for MSs. Therefore, the AP and the MSs can carry out seamless handover for Super Wi-Fi service. A performance evaluation shows that the proposed scheme is superior to the conventional Wi-Fi in channel mobility delay.