• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2627-2640
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• 1998

In this paper, we analyze the performance of the virtual cell system[1] for the transmission of IP datagrams in mobile computer communications. A virtual cell consistsof a group of physical cells shose base stationsl are implemented b recote bridges and interconnected via high speed datagram packet switched networks. Host mobility is supported at the data link layer using the distributed hierachical location information of mobile hosts. Given mobility and communication ptems among physical cells, the problem of deploying virtual cells is equivalent to the optimization cost for the entire system where interclster communication is more expesive than intracluster communication[2]. Once an iptimal partitionof disjoint clusters is obtained, we deploy the virtual cell system according to the topology of the optimal partition such that each virtual cell correspods to a cluser. To analyze the performance of the virtual cell system, we adopt a BCMP open multipel class queueing network model. In addition to mobility and communication patterns, among physical cells, the topology of the virtual cell system is used to determine service transition probabilities of the queueing network model. With various system parameters, we conduct interesting sensitivity analyses to determine network design tradeoffs. The first application of the proposed model is to determine an adequate network bandwidth for base station networking such that the networks would not become an bottleneck. We also evaluate the network vlilization and system response time due to various types of messages. For instance, when the mobile hosts begin moving fast, the migration rate will be increased. This results of the performance analysis provide a good evidence in demonsratc the sysem effciency under different assumptions of mobility and communication patterns.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.714-719
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• 2005

The paper attempts to design and implement the system which can remotely check visitors' speech or Image by a mobile phone. This system is designed to recognize who a visitor is through the automatic calling service, not through a short message, via the mobile phone, even when the home owner is outside. In general, door locks are controlled through the home Server, but it is more effective to control door locks by using DTMF signal from a real-time point of view. The technology suggested in this paper makes it possible to communicate between the visiter and the home owner by making a phone call to tile home owner's mobile phone automatically when the visiter visits the house even if the home owner is outside, and if necessary, it allows for the home owner to control the door lock remotely. Thanks to the system, the home owner is not restricted by time or space for checking the visitor's identification and controlling the door lock. In addition, the security system is improved by changing from the existing password form to the combination of password and speaker verification lot the verification procedure required for controlling the door lock and setting the environment under consideration of any disadvantages which may occur when the mobile Phone is lost. Also, any existing problems such as reconnection to tile network for controlling tile door lock are solved by controlling the door lock in real time by use of DTMF signal while on the phone.

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.568-583
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• 1994

In the changing social and economic conditions, reorientation of the health care system is a process of rearranging health care resources keeping in mind the appropriativeness, relevancy, and efficacy of health care programs. Also it has been recognized recently that the CHP program is in need of review for the same reasons, that is to say, the ease in which health care facilities are available, the high rate of coverage with insurance and the development of an effective transportation system. Therefore there is a social inclination to think that there are no remote areas and to question the roles of public health facilities, health centers, health sub centers and CHP posts. This paper was done to review problems and to propose new directions for the CHP system. The findings of this study are as follows ; 1) It is necessary that primary health care should be simplified into three parts, medical treatment, preventive care services and the organization of administration and logistics. Also each department should be supplemented with the appropriate professional personnel in order to develop a task oriented system. The reorientation of the CHP system should be managed in keeping with that of other public health care systems. Therefore it is necessary to look at the CHP system problems as one aspect of the reorientation process of public health care systems, and to work to find new ways to address these problems. 2) The location of the CHP post should be decided by the needs of the community in both the medical and preventive areas. If the people have a minimum need, the location of the CHP post should be altered and the existing roles of the CHP should be modified to allow for flexibility according to the community needs. 3) Use of the problem solving method in regular team meetings will prove to be as efficient as continuing education programs in improving job competancy. 4) The supervision of CHP's activities should be made by the same type professional personnel, that is, senior CHPs or charge nurses in the public health center at the county level. 5) The operational expensies of CHP post should be supported by the administrative department of the public health center and should create working conditions that will allow the CHP to concentrate on community health service programs. 6) The organizations for community participation, working committees, community health workers and a number of the local assembly, should be activated to provide for participation in finding solutions to health related problems in the com-munity.

• The KIPS Transactions:PartA
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• v.10A no.5
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• pp.529-538
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• 2003

The speedy development of the world-wide web is rapidly growing the internet-based tools for the remote instruction. In interchanging and expressing the information of one another on the web, it is produced through the form of HTML(Hyoertext Text Markup Language). However, the structural disadvantage of the HTML is becoming to require a powerful XML(eXtensible Markup Language) which can store all the sphere of data, and transform them into another form. Nevertheless, because the powerful XML(eXtensible Markup Language). However necessary that XML standard should be applied appropriately. Because existing lecture data of cyber education sites cannot be shared, the users should passively use only the functions offered by cyber school. To solve the problem of this limit, in this study, the standardized data structure for XML is defined, and system model for processing between the server and the client is provided. By storing the lecture data of cyber education sites as XML on the web, stored data came to be reused without changing on any site. In the view of Users, they could used the Internet service with equipment that they want at any place and any time. To control any kinds of CK\LMS(Cyber Lecture Management System) for Administrator and Users, we offered a variety of Multimedia applications and an easy interface and built a new style of CLMS. Therefore, by strong and extracting the data related with the virtual education of the secondary school through the form of XML, for the effective interchange and sharing of the information, maximum utilization of the information can be achieved.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.5
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• pp.41-48
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• 2005

OSGi(Open Service Gateway Initiative) offers a unique opportunity for pervasive computing as a potential framework for achieving interoperability between various sensors, home appliances, and networked devices. The OSGi framework supports a remote installation of a bundle, which is a unit that installs and deploys services. However, in order for the bundle in execution to migrate, a specific form of bundle such a mobile agent, is needed one which is able to move through a heterogeneous network. This paper proposes a method that can manage bundles like these dynamic agents, in order to ensure the mobility of entities in multiple OSGi framework environments. For our purposes, we have designed the mobile agent management system for managing the lifecycle and mobility of agents in the OSGi framework. The mobile agent management system we are proposing implements a bundle form which can perform in an OSGi framework as well as manage autonomous mobile services. As a result, mobility in a pervasive environment will be supported more efficiently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4536-4542
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• 2011

RFID technology uses communication through the use of radio waves to transfer data between a reader and an electronic tag attached to an object for the purpose of identification and tracking. RFID technology can be applied to the various service areas such as, position determination technology, remote processing management and information exchange between objects by collecting, storing, processing, and tracing their informations from the tag attached to the objects using electronic wave by recognizing the information and environment of those objects. However, to revitalize these various services, it is important to test the RFID tag performance. But There are few instructions which have and hold the RFID emulator technology for organizing the RFID international test environment. Also there are not many manufacturing companies which recognize about the exact RFID test standard and requirements for the International Standards. In this paper, a construction of Tag Performance test environments and test methods are suggested which are required by EPCglobal or ISO/IEC. Details about RFID Tag performance test items proposed by ISO/IEC FDIS 18046-3 are explained, performed RFID Tag performance test through the performing test against each measured item, and draw a result for the RFID Tag performance of International Standards.

• Journal of Korean Society of Transportation
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• v.26 no.6
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• pp.39-47
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• 2008

With dramatic development of IT technology and start of DMB service, installing the DMB equipment in a vehicle for watching TV programs and literal or pictorial traffic information are increasing. Watching the DMB during driving the vehicle could cause visual and cognitive distraction to drivers as much as eating food, operating radio and using mobile phone. However, there is not much empirical research for this topic and no research examined the effect of watching the DMB on driving behaviors in Korea. So, the present study examined the effect of watching the DMB on the driving behaviors with car simulator experiment. Within subject design was used in the study. That is, all subjects drove the vehicle both in the watching DMB condition and the non-watching DMB condition. The results indicated that subjects in the watching DMB condition took longer time to arrive at the destination and operated accelerator and brake pedal rapidly than subjects in the non-watching DMB condition. That is, their overall driving stability was lower than non-watching subjects'. Additionally, we examined the difference among the DMB control conditions (i.e., keypad condition, touch-pad condition and remote controller condition) in the driving behaviors. Finally, we discussed the limitations and the implications of the present study.

• Journal of Cadastre & Land InformatiX
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• v.49 no.2
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• pp.135-149
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• 2019

This article analyzed economic effects of changes in spatial accessibility on regional touruism expenditure structure resulting from highway investments on Gangwon province, Korea. The Seemingly Unrelated Regress(SUR) model is applied to analyze the structure of change in tourism expenditure of Gangwon Province, and the competition and complementary relationship of tourist demand were analyzed among 18 counties in Gangwon by Dendrinos-Sonis method. The spatial accessibility has a significant effect on the increase in amount of tourist expenditure, but by 1% increase in the accessibility resulted in a reduction of length of stay -0.18% and travel costs -0.34% by respectively. The most powerful variable for improving the on-site economy is the tourist service establishment, which increases one unit, the amount of tourist expenditure increased by 3.6%. Moreover, the competition and supplemental relationship of tourism demands in Gangwon was decided by the conditions under which traffic flow with passing occurred, such as inland or ocean-typed travel attractions, adjacent or remote regions to the highway. The limitations of this study were not able to use raw data of tourism expenditures before and after the opening the highway due to the restriction of priority data, and further research on the appropriate level of spatial accessibility for the regional economy is needed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.261-269
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• 1989

Agricultural activities in Chejudo require more specialized weather services in this region. The meteorological information available from the Korea Meteorological Service (KMS) is limited in its areal coverage because the KMS stations are located along the narrow band of coastal area. topoclimatological technique which makes use of empirical relationships between the topography and the weather can be applied to produce reasonable estimates of the climatic variables such as air temperature and precipitation over remote land area where routine observations are rare. Presentation of these estimates in a from of fine-mesh grid map can also be helpful to upgrade the quality of weather services in this region. Altitude values of the 250 m grid points were read from a 1: 25000 topographic map and the mean altitude, the mean slope, and the aspect of the slope were determined for each 1 km$^2$ land area from these altitude data. Daily minimum air temperature data were collected from 18 points in Chejudo during the winter period from November 1987 to February 1988. The data were grouped into 3 sets based on synoptic pressure pattern. Departures from the KMS observations were regressed to the topographical variables to delineate empirical relationships between the local minimum temperature under specific pressure patterns and the site topography. The selected regression equations were used to calculate the daily minimum temperature for each 1 km$^2$ land area under the specific pressure patterns. The outputs were presented in a fine-mesh grid map with a 6-level contour capability.

• Journal of Internet Computing and Services
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• v.15 no.5
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• pp.83-93
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• 2014

Providing personalized services customized to users' needs and preferences becomes highlighted as a key area of user-context computing. It is essential for context-aware technology to be developed more intelligent and meaningful services by being widely applied to a variety of sectors and domains. SDO (Standard Development Organization) such as MPEG and W3C has been actively developed to be standardized services and to improve context-awareness services. Yet current standards related to context-aware technology, such as MPEG-7, MPEG-21, MPEG-V, and emotionML, are not capable enough to support various systems and diverse services. Against this backdrop, the MPEG User Description, referred to also as MPEG-UD Standard, is to ensure interoperability among recommendation services, which take into account user's context when generating recommendations to users. In this light, we introduce standards related to the user context and propose the structure for RD-Engine and the Remote Responsive User Interface(RRUI) system in reference to MPEG-UD. This system collects unit resources matching specific condition according to the user's contexts described by MPEG-UD. In so doing, it improves adaptive user interface considering device features in real-time. By automatically generating adaptive user interfaces tailored to an individual's contexts, the proposed system aims to achieve high-quality user experience for a complex service.