• Korean Journal of Social Welfare
• /
• v.56 no.4
• /
• pp.269-290
• /
• 2004

The purpose of this study was to examine the impact of psychosocial protective and risk factors on problem drinking among American adolescents. In addition, this study investigated the compensatory and buffering effects of psychosocial protective factors. The sample consisted 4,362 10th graders taken from the Monitoring the Future Study 2002. This study performed the hierarchical regression analysis for data analyses. The main findings provided that friend influence, sensation-seeking, and tolerance of deviance had significant positive relationships with problem drinking as risk factors. This study also revealed that negative perception on drinking, parental bonding, school bonding, and prosocial activity had significant direct impacts in decreasing problem drinking, which explains the compensatory effect of protective factors. Additionally, this study showed that negative perception on drinking had a significant buffering effect moderating friend influence on adolescents' opportunities exposed to problem drinking. The results of this study suggest some practical implications for preventive intervention programs that target adolescent problem drinking.

• Journal of the Korea Safety Management & Science
• /
• v.12 no.1
• /
• pp.35-42
• /
• 2010

Due to the industrialization and urbanization, the transport of hazardous materials increases, which rises possibilities in occurring prospective accidents in terms of hazardous material transport as well. This study applied the model developed from the previous research to analyze the scale of damage areas from the accidents related to hazardous material accidents, as well as suggested a method to measure automatically the scale of accident including casualties and environmental damage based on the guideline which suggests the quantities of hazardous materials exposed from an accident and was defined in the study of standardization for hazardous material classification. A buffering analysis technique of Geographic Information System (GIS) was applied for that. To apply the model which evaluates the scale of population and exposure to environment on each link, rail network, zones, rail accident data, rail freight trips, and locations of rivers etc were complied as a database for GIS analysis. In conclusion, a method to measure damage areas by the types of hazardous materials was introduced using a Clip and a Special Join technique for overlay analysis.

• The Journal of the Korea Contents Association
• /
• v.9 no.10
• /
• pp.258-267
• /
• 2009

This study purposed to develop GIS model for evaluating hospital location in a metropolitan city. Secondly, the suitability score of hospital was compared with the number of outpatient/inpatients of hospitals. This study used administrative data collected from the annual report of the 5 ward offices from Daejeon in Korea in 2004. 7 Acute care hospitals operated in Daejeon in 2004 were selected for the analysis. The suitability of hospitals in a metropolitan city was evaluated by the economic factors which were assumed to influence the health care demand. Each criterion was measured from each Dong. Correlation coefficients between the suitability score of hospital and the number of patients were varied depending on the buffering size. The relationship showed positive relationship with the number of inpatient (0.15) and outpatients (0.10) on the 0.5km buffering size. However, the correlation coefficients were changed to a negative direction or decreased when the buffering size was increased to 1.0km, 1.5km, and 2.0km.

• Perspectives in Nursing Science
• /
• v.13 no.2
• /
• pp.70-80
• /
• 2016

Purpose: This study examined the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea, focusing on the buffering effects of social support. Methods: We included 132 completed questionnaires in the analysis. The buffering effect was examined using a hierarchical regression analysis by adding interaction terms. Results: Health promotion scores were significantly higher in the group with a higher education level, lower depressive symptom scores, and higher levels of social support. However, no statistically significant differences were found in the health promotion behaviors by gender, age, spouse, job, financial stability, subjective health status, chronic disease, regular health checkups, or acculturation stress. The hierarchical regression analysis demonstrated that social support had a buffering effect on the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants. Specifically, the relationship between the acculturation stress stemming from the difficulties in the workplace and health promotion behaviors was attenuated by social support. Conclusion: These findings indicate that social support significantly moderates the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea. A variety of strategies to enhance social support should be incorporated in the health promotion programs to decrease the negative effects of acculturation stress in the Korean Chinese elderly living in Korea.

• Journal of Korea Multimedia Society
• /
• v.14 no.1
• /
• pp.54-75
• /
• 2011

PoC(Push-to-talk Over Cellular) is an integrated technology of group voice calls, video calls and internet based multimedia services. If a PoC user can not participate in the PoC session for various reasons such as an emergency situation, lack of battery capacity, then the user can use the PoC Box which has a similar functionality to the MM Box in the MMS(Multimedia Messaging Service). The RTSP(Real-Time Streaming Protocol) method is recommended to be used when there is a transmission session between the PoC box and a terminal. Since the existing VOD service uses a wired network, the packet size of RTSP-based VOD service is huge, however, the PoC service has wireless communication environments which have general characteristics to be used in RTSP method. Packet loss in a wired communication environments is relatively less than that in wireless communication environment, therefore, a buffering latency occurs in PoC service due to a play-out delay which means an asynchronous play of audio & video contents. Those problems make a user to be difficult to find the information they want when the media contents are played-out. In this paper, the following techniques and methods were proposed and their performance and superiority were verified through testing: cross-over dual reception buffering technique, advance partition multi-reception buffering technique, and on-demand multi-reception buffering technique, which are designed for effective picking up of information in media content being transmitted in short amount of time using RTSP when a user searches for media, as well as for reduction in playback delay; and same-priority packetization transmission method and priority-based packetization transmission method, which are media data packetization methods for transmission. From the simulation of functional evaluation, we could find that the proposed multiple receiving buffering and packetizing methods are superior, with respect to the media retrieval inclination, to the existing single receiving buffering method by 6-9 points from the viewpoint of effectiveness and excellence. Among them, especially, on-demand multiple receiving buffering technology with same-priority packetization transmission method is able to manage the media search inclination promptly to the requests of users by showing superiority of 3-24 points above compared to other combination methods. In addition, users could find the information they want much quickly since large amount of informations are received in a focused media retrieval period within a short time.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.11 no.2
• /
• pp.1-12
• /
• 2008

This paper identifies public transit-poors and derives spatial characteristics of the poors' distribution in an urban area by utilizing buffering analysis of geographic information systems and remote sensing techniques in the case of Daegu metropolitan city. Since special attention is given to elderlies, this study assigns three hundred meter buffer from bus/subway station as service boundary for elderlies. The results of this study tell us that 1) the transit-poors are concentrated on suburban and rural regions, 2) high proportions of the transit poors are elderlies with spatial variations in many regions, 3) the main housing type of the transit-poors is single detached house. We expect that this study can contribute to build an effective policy-making by showing essential technical processes and methods in identifying policy-need groups and their characteristics of spatial distribution.

• Journal of Digital Convergence
• /
• v.6 no.2
• /
• pp.117-125
• /
• 2008

High-volume web sites often use clusters of servers with load balancing as a way to increase the performance, scalability, and availability of the sites. Load balancing, usually performed by load balancer in front of such clusters, is a technique to spread workload between several computers or resources, in order to get optimal resource utilization or response time. In this paper we examine the performance for several configurations of cluster-based web servers using a simulation approach. We investigate two types of buffering scheme (common and local) for web clusters and three load balancing policies (uniformly random, round robin, and least queue first), using response time as a performance measure. We also examine two basic approaches of scaling web clusters: adding more servers of same type or upgrading the capacity of the servers in the clusters.

• ETRI Journal
• /
• v.17 no.1
• /
• pp.23-36
• /
• 1995

We present a performance evaluation model of cell reassembly mechanism in an ATM switching system. An ATM switching system may be designed so that communications between processors of its control part can be performed via its switching network rather than a separate inter-processor communications network. In such a system, there should be interface to convert inter-processor communication traffic from message format to cell format and vice versa, that is, mechanisms to perform the segmentation and reassembly sublayer. In this paper, we employ a continuous-time Markov chain for the performance evaluation model of cell reassembly mechanism with individual buffering, judicially defining the states of the mechanism. Performance measures such as message loss probability and average reassembly delay are obtained in closed forms. Some numerical illustrations are given for the performance analysis and dimensioning of the cell reassembly mechanism.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.12 no.1
• /
• pp.64-72
• /
• 2009

The method to generate a digital elevation model(DEM) from contour lines causes a problem in which the low relief landform cannot be clearly presented due to the fact that it is significantly influenced by the expression of micro landform elements according to the interval of contours. Thus, this study attempts to develop a landcover burning method that recovers the micro relief landform of the DEM, which applies buffering and map algebra methods by inputting the elevation information to the landcover. In the recovering process of the micro landform, the DEM was recovered using the buffering method and elevation information through the map algebra for the landcover element for the micro landform among the primary DEM generation, making landcover map, and landcover elements. The recovering of the micro landform was applied based on stream landforms. The recovering of landforms using the buffering method was performed for the bar, which is a polygonal element, and wetland according to the properties of concave/convex through generating contours with a uniform interval in which the elevation information applied to the recovered landform. In the case of the linear elements, such as bank, road, waterway, and tributary, the landform can be recovered by using the elevation information through applying a map algebra function. Because the polygonal elements, such as stream channel, river terrace, and artificial objects (farmlands) are determined as a flat property, these are recovered by inputting constant elevation values. The results of this study were compared and analyzed for the degree of landform expression between the original DEM and the recovered DEM. In the results of the analysis, the DEM produced by using the conventional method showed few expressions in micro landform elements. The method developed in this study well described wetland, bar, landform around rivers, farmland, bank, river terrace, and artificial objects. It can be expected that the results of this study contribute to the classification and analysis of micro landforms, plain and the ecology and environment study that requires the recovering of micro landforms around streams and rivers.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.43 no.5
• /
• pp.1-12
• /
• 2015

This study analyzes the physiological healing effects on users according to forest types. Forest types are classified into Chamaecyparis obtusa, Quercus serrata and Pinus densiflora and the subjects of this study, 64 hypertensives, 59 diabetics and 59 ordinary people, were tested to observe their physiological effects. The index of physiological reaction comprises electroencephalogram(EEG), heart rate variability(HRV), blood pressure and cortisol level. An analysis of the stress-buffering effect from the physiological reactions of the overall subjects indicates that Quercus serrata forests have a higher stress-buffering effect than others in terms of central nervous, endocrine and autonomic nervous systems. Chamaecyparis obtusa forests are contributory to soothing stress in the central nervous and endocrine systems. Pinus densiflora forests contribute in some indexes of the endocrine and autonomic nervous systems. In contrast, Pinus densiflora forests are less influential on a stress-buffering effect than the other two. In the level of the effect for lowering blood pressure, Chamaecyparis obtusa and Quercus serrata forests are more effective than Pinus densiflora forests. Therefore, staying in the first two forests can heighten the healing effect of the lowering of blood pressure for hypertensive patients. Every forest is efficacious to lowering diabetic blood glucose levels. Spending time in Quercus serrata forests is more effective for hypoglycemic.