• Journal of KIISE:Information Networking
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• v.30 no.5
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• pp.595-603
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• 2003

To provide mobile nodes with continuous communication services, it is important to reduce the packet losses during handoffs. The handoffs of mobile nodes cause packet losses and decrease of TCP throughput on account of a variety of factors. One of those is the congestion in the new cell. Due to the congestion, not only the node moving into the cell but also the already existing nodes that were successfully communicating in the cell suffer the performance degradation. In this paper we propose a new handoff mechanism called‘packet freeze control’, which avoids the congestion caused by handoffs by regulating the influx of traffic burst into the new cell. Packet freeze control is applicable to a wireless network domain in which FAs(Foreign Agents) are connected hierarchically and constitute a logical tree. It gradually increases the number of packets transferred to the new cell by buffering packets in the FAs on the packet delivery path over the wireless network domain. The simulation results show that the proposed mechanism not only reduces the packet losses but also enhances the TCP throughput of other mobile nodes in the cell.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.26-36
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• 2013

Highway traffic safety evaluation of area on the basis of the accident rate has a limitation, thus its result is dependent on the exposure variables. It works an obstacle to decision making for effective budget execution. In this paper, we developed a methodology of taking simultaneously macroscopic exposure indicators into account in evaluating the safety using least squares method. The weight of exposure indicators to make up of highway traffic safety evaluation index is that accident rate per population, accident rate per registration vehicle and accident rate per length of road is 0.29, 0.52 and 0.19 respectively and calculated the highway traffic safety index of total local governments in Korea. The methodology to calculate highway traffic safety evaluation index proposed in this paper can be utilized in executing the traffic safety policies to increase the efficiency of investment about traffic safety budget.

• Korea journal of population studies
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• v.8 no.2
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• pp.46-67
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• 1985

In this paper, an attempt has been made to examine the pattern of mortality in Korea during 1970~80. By applying the age-sex specific mortality rates quoted from 1978~79 life tables for Korea published by NBOS, EPB to those of the West pattern of regional model life tables and the far eastern pattern of model life tables for developing countries, life expectancy at birth were calculated. Also the author reviewed the trends of death rates, life expectancy and cause of death using vital registration data and other materials. Summarized results are as follows; 1. Crude death rates in Korea was reduced to one fifth in the 1983 compared to that in 1920's. Life expectancy also improved to almost double in 1985 compared to 1920's. But the difference in the life expectancy between male and female increased during that period and it was recorded as 6.4 years in 1985. This discrepancy was mainly due to the different tempo of decreasing in mortality level by sex, particularly, for the age 40 and above. 2. For the pattern of mortality in Korea, it showed that female mortality could accounted closer to the West pattern model life tables. There were high similarity between actual pattern prevalent in Korea and West pattern. And its coefficient of variance was also very low. However for the case of male, it was difficult to find the exact model life tables for explaining the actual situation on the male mortality pattern which means exist considerable dissimilarity in older ages. The Far eastern pattern of U.N. model life tables show better results than West pattern, however, the deviation of the pattern to actual was severe. Also in Far eastern pattern, high coefficient of variance was existed. Furthermore it was found in the paper that the mortality level of Korean male for the age 40 and above were much higher than that of Far eastern pattern which was reflected the high mortality of the male adult in Far east region. 3. The analysis of cause of death showed that circulatory disease such as cerebrovascular disease and hypertensive disease accounted for the leading cause of death in Korea for the age 40 and above. There should he paid special attention to chronic retrogressive diseases for the older age groups. For younger age groups, injury and poisoning were reported as important cause of death.

• Journal of the Korea Convergence Society
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• v.10 no.5
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• pp.341-349
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• 2019

The purpose of this study is to analyze the problems facing the youth soccer league(i-league) and present their development directions. The study method used focus group interviews. The results of the study are summarized into three: First, promotion and regional league operation were highlighted as problems of i-League and the solution was the unification system of the Korean Olympic Committee(KOC) and the Korea Football Association(KFA), and the operation of each region by itself. Second, issues resulting from the integration of youth club league and i-league were revealed as level differences by teams and leak of the motivation for winning. Operation of the elevating system was proposed as a solution, and such as fare play team award, voluntary activity team award will derive important virtues for youth. Third, KOC and KFA need additional support for various environments and administrative areas such as facility security, training for leaders and officials, and registration of players.

• Research in Community and Public Health Nursing
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• v.32 no.1
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• pp.107-115
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• 2021

Purpose: The purpose of this study is to identify factors associated with smoking relapse within six months after quit attempts among workers in small and medium-sized enterprises in South Korea. Methods: The analysis was conducted for a total of 194 people who attempted to quit smoking by applying for a smoking cessation support service at the Regional Tobacco Control Center. The data used in the study were extracted from the Smoking Cessation Service Integrated Information System. Kaplan-Meier estimator and Cox proportional hazards regression model were used to identify variables associated with smoking relapse within six months' time period. Results: Smoking relapse rate within six months was 66.0%, and variables associated with relapse included the cases such as carbon monoxide (CO) at the time of registration (HR: 2.15, 95% CI: 1.10~4.22 for CO ≥20 ppm or more vs.CO <10 ppm), the average number of cigarettes smoked per day (HR: 1.04, 95% CI: 1.00~1.07), and the number of counseling(HR: 0.60, 95% CI: 0.54~0.67). Conclusion: Smoking characteristics and counseling showed one of the strongest correlations with relapse within six months. This implies that it is necessary to understand the smoking characteristics and patterns of workers and to provide continuous smoking cessation counseling tailored to individual characteristics for effective smoking relapse prevention.

• Journal of Korean Society of Archives and Records Management
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• v.23 no.1
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• pp.127-132
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• 2023

The Incheon Medical Center Institutional Review Board (IRB), a department that reflects the characteristics of Incheon Medical Center, a medical and public institution, was established in 2013. IRB contributes to performing its role as a local accountable care hospital and protecting researchers and subjects by proving the ethics of research conducted at the medical center. So far, IRB has reviewed a total of 80 research proposals for human subject research and human-derived material research, and it currently exists as an independent department directly under the president of the medical center. This paper aims to explain the registration and preservation of IRB-related records, the maintenance of the Records Management Standard Table and related regulations, and archives, as well as to present limitations and improvements in the disclosure, utilization, and classification of records.

• Journal of the Korean Regional Science Association
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• v.36 no.1
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• pp.51-67
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• 2020

The purpose of this study is to estimate the housing area per capita for verifying if the public Big Data, of the building ledger and resident registration ledger, can be used as well as the National Census and Housing Survey. The Mankiw and Weil (MW) model was constructed by extracting samples of general detached houses and flat houses from the public big data, and compared with the result from traditional survey method. Then, the MW models of 25 municipalities in Seoul was established. As a result, it can be confirmed that it is possible to establish MW models comparable to regular surveys using public big data, and to establish a model for each basic localities which was difficult to use as a regular survey method. Public Big Data has the advantage of expanding the knowledge frontier, but there are some limitations because it uses data generated for other original purposes. Also, the difficult process of accessing personal information is a burden to carry out analysis. It is expected that continuing research should be needed on how public Big Data would be processed to complement or replace traditional statistical surveys.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.51-55
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• 2009

Jayoung was bred within the potato breeding program of Highland Agriculture Research Center (HARC), National Institute of Crop Science. It was originated from a cross made between Atlantic as a female and AG34314 as a male parent in 2003. Jayoung was evaluated as a clone number Daegwan 1-104 for the growth and tuber characteristics, yielding ability, and resistance to major potato diseases in the regional yield trials from 2006 to 2007. Finally, this clone was renamed as Jayoung and was presented to Korean Seed & Variety Service in 2007 for registration as a new potato cultivar. Jayoung has a oval shape, shallow eye depth, dark purple skinned and fleshed tuber characteristics. Its mean tuber yields from the regional yield trials was 37.3 MT/ha, and it showed the highest yield in spring cropping. Jayoung showed high resistance to both common scab (Streptomyces scabies) and potato leaf roll virus (PLRV), however it was susceptible to late blight (Phytophthora infestans). The dry matter content of Jayoung was fairy high 20.3%, therefore it is suitable for both chip processing and table usage. Its anthocyanin content was the highest in autumn cropping as 43.7 mg/100 g fresh weight and its mean anthocyanin content was 4.7 times higher than that of Jasim.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.502-506
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• 2009

"Hongyoung" was bred within the potato breeding program of National Institute of Highland Agriculture (NIHA). It was originated from a cross made between Atlantic as a female and AG34314 as a male parent in 2003. "Hongyoung" was evaluated as a clone number Daegwan 1-102 for the growth and tuber characteristics, yielding ability, and resistance to major diseases in the regional yield trials from 2006 to 2007. Finally, this clone was renamed as "Hongyoung" and was presented to Korean Seed & Variety Service in 2007 for registration as a new potato cultivar. "Hongyoung" has a round shape, shallow eye depth, red skinned and fleshed tuber characteristics. Its mean tuber yields from the regional yield trials was 37.4 MT/ha, and it showed the highest yield in spring cropping. "Hongyoung" showed high resistance to common scab (Streptomyces scabies) and potato leaf roll virus (PLRV), however it was susceptible to both potato virus Y (PVY) and late blight (Phytophthora infestans). The dry matter content of "Hongyoung" was low to medium 17.7%, therefore it is suitable for table use. Its anthocyanin content was the highest in autumn cropping with 31.8 mg/100g fresh weight and it contained 3.6 times higher anthocyanin than the control, Jasim.

• Korean Journal of Remote Sensing
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• v.31 no.5
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• pp.449-459
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• 2015

The conventional National Forest Inventory(NFI)-based forest carbon stock estimation method is suitable for national-scale estimation, but is not for regional-scale estimation due to the lack of NFI plots. In this study, for the purpose of regional-scale carbon stock estimation, we created grid-based forest carbon stock maps using spatial ancillary data and two types of up-scaling methods. Chungnam province was chosen to represent the study area and for which the $5^{th}$ NFI (2006~2009) data was collected. The first method (method 1) selects forest type map as ancillary data and uses regression model for forest carbon stock estimation, whereas the second method (method 2) uses satellite imagery and k-Nearest Neighbor(k-NN) algorithm. Additionally, in order to consider uncertainty effects, the final AGB carbon stock maps were generated by performing 200 iterative processes with Monte Carlo simulation. As a result, compared to the NFI-based estimation(21,136,911 tonC), the total carbon stock was over-estimated by method 1(22,948,151 tonC), but was under-estimated by method 2(19,750,315 tonC). In the paired T-test with 186 independent data, the average carbon stock estimation by the NFI-based method was statistically different from method2(p<0.01), but was not different from method1(p>0.01). In particular, by means of Monte Carlo simulation, it was found that the smoothing effect of k-NN algorithm and mis-registration error between NFI plots and satellite image can lead to large uncertainty in carbon stock estimation. Although method 1 was found suitable for carbon stock estimation of forest stands that feature heterogeneous trees in Korea, satellite-based method is still in demand to provide periodic estimates of un-investigated, large forest area. In these respects, future work will focus on spatial and temporal extent of study area and robust carbon stock estimation with various satellite images and estimation methods.