• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.272-287
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• 2013

This paper describes the importance of selecting explanatory variables(e.g. land price determinants) in hedonic pricing models employed in predicting real estate price, and explores dynamics of the land price determinants over time. The City of Junju was chosen as the study area, and repeated measured price data of standard lots over 17 years were analyzed. We applied a three-level modeling approach to this data in consideration of its nested data structure and longitudinal characteristics. Main land price determinants we focused on are primarily based on items included in the standard comparison table of land price, which is an official hedonic pricing model used by Government to estimate land price for tax levy. Our result shows that the land price fluctuation over 17 years was not uniform over the whole study area with each neighborhood revealing different price trend, and as such warrants longitudinal model components. In addition, some of determinants previously recognized as important were proved insignificant. It was also found that significant determinants at a particular time point lost its power gradually over time and vice versa. It is expected that more accurate prediction of price would be possible when taken account for this dynamics of price determinants over time in applying hedonic pricing model method.

• Korean Journal of Social Welfare
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• v.56 no.3
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• pp.279-301
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• 2004

Relations of factors associated with burnout were investigated among 124 child protective service workers currently working in Korean Child Abuse Prevention Centers nationwide. Three categories of factors associated with burnout were examined; (1) individual characteristics, (2) job-related characteristics, and (3) job-satisfaction. Social survey method using questionnaires by mail was employed. MBI(Maslach Burnout Inventory) for measuring burnout, a part of Smith, Kendal & Hulin's JDI(Job Description Index) for job-satisfaction, and a scale measuring the special characteristics of job developed by researchers were used. Mann-Whitney test and Kruskal-Wallis test were employed to analyze the data. Across all burnout sub-scales(emotional depletion, dehumanization of clients, lack of feelings of achievement), subjects reported a high degree(above the cutting point) of burnout. Several factors were identified as associated with burnout. Child protective service workers who are young, single with front line worker status reported higher burnout. Lack of education and training before the job location were another factors which contributed to worker burnout. Lack of proper supervision stood out as another burnout provoking factor. Job-satisfaction was negatively correlated with all three burnout sub-scales, which meant the lower the job-satisfaction, the higher the burnout of service workers. The findings implicate that the administrators of Child Abuse Prevention Centers should pay close attention to their workers' sign of burnout and develop carefully designed support system which include provision of excellent supervision, proper education and training opportunities and organizational effort to strengthen employees' overall job-satisfaction to secure their quality of services toward abused children and their family.

• Journal of Korea Port Economic Association
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• v.32 no.2
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• pp.105-122
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• 2016

Numerous studies have evaluated the status of seaports. However, the majority of the research has approached this topic from the view-point of port capabilities, including locational advantage, infrastructure, productivity, and competitiveness. The position and/or role of a port can be understood more precisely and comprehensively by considering the interconnectivity among ports making up enormous global transportation networks. The main objective of this study is to compare the status of 82 container ports on the trunk shipping routes between Asia and Europe by applying the concepts of structural equivalence and role equivalence proposed by the social network analysis method. Network similarities and differences among competing ports in the regions are assessed by analysing their structural equivalence. Furthermore, the hierarchical structures of the ports located on the trunks between Asia and Northwest Europe and between Asia and the Mediterranean are constructed by evaluating their role equivalence. The results of this empirical research shows that Singapore and Rotterdam possess the most significant positions on the ocean corridors between Asia and Northwest Europe. Singapore also holds a leading position on the Asia-Mediterranean shipping route. Lastly, no ports located in the Middle East or Mediterranean regions have an equivalent weight to those of Rotterdam, Hamburg, Antwerp on the Asia-Northwest Europe route.

• Journal of Preventive Medicine and Public Health
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• v.30 no.2 s.57
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• pp.392-401
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• 1997

Generally working environment and worker's health status of small scale industries (SSI) which employ less than 50 workers are known to be poorer than those of large scale industries(LSI) which employ more than 500 workers. However, according to the analysis of occupational injuries in Korea, prevalence rate of occupational injuries of SSI was 3.1 times as high as LSI. But there was no difference in prevalence rate of occupational disease and werkers with suspected occupational disease(D1) between SSI and LSI. To confirm these two different facts, we surveyed working environment and worker's health status of SSI and LSI in Kyeungin industrial complex. Workers in SSI were 10,878 and workers in LSI were 8,291 and number of hazardous agents in SSI were 3,554 and those of LSI were 1,916. We found following results. First, proportion of male workers and workers who were less than 30 yens old and more than 50 yens old was higher in SSI compared to LSI. Second, worker in SSI had more liver disease, viral hepatitis, and pneumoconiosis than in LSI, and there were more worker with suspected occupational disease, general disease, and worker needed close observation in SSI. But these effects had not statistical significance under the condition controlled by age and sex with logistic regression. Third, the numbers measured for specific chemicals, organic solvents, and heavy metals in SSI was more than in LSI. However there was on difference in the excess rate of each hazardous agent between SSI and LSI. As the above results workers' health status in SSI was poorer than in LSI, but these results were mainly due to the population structure difference. Although there were some limitation of this study and problems of sensitivity and validity for periodic health examination and working environment evaluation method, the concept that working environment and worker's health status in SSI should be reviewed. In future the study that will reveal the real weak point of SSI should be performed.

• Journal of the Korean Geotechnical Society
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• v.19 no.3
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• pp.53-64
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• 2003

Many transmission towers, high-rise buildings and bridges are constructed near steep slopes and are supported by large-diameter piles. These structures may be subjected to large lateral loads, such as violent winds and earthquakes. Widely used types of foundations for these structures are pier foundations, which have large-diameters with high stiffness. The behavior of a pier foundation subjected to lateral loads is similar to that of a short rigid pile because both elements seem to fail by rotation developing passive resistance on opposite faces above and below the rotation point, unlike the behavior of a long flexible pile. This paper describes the results of several numerical studies performed with a three-dimensional finite element method (FEM) of model tests of a laterally loaded short pile located near slopes, respectively. In this paper, the results of model tests of single piles and pile groups subjected to lateral loading, in homogeneous sand with 30$^{\circ}$ slopes and horizontal ground were analyzed by the 3-D FE analyses. The pile was assumed to be linearly elastic. The sand was assumed to have non-associative characteristics, following the MC-DP model. The failure criterion is governed by the Mohr-Coulomb equation and the plastic potential is given by the Drucker-Prager equation. The main purpose of this paper is the validation of the 3-D elasto-plastic FEM by comparisons with the experimental data.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.250-256
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• 2006

The revision of radio waves act, which took effect on July 1,2005, widened the bandwidth of PLC from $9kHz{\sim}450kHz$ to $9kHz{\sim}30MHz$. This high upper limit of frequency may cause the interference in HF wireless communications. From this point of view, the goal of this research is to suggest the estimation method of whether-or-not the interference occurs and furthermore offer countermeasures to avoid it hereafter. Ministry of Information and Communication Radio Research Laboratory(MIC-RRL)has been researching for the interference and devoting themselves to turn out how much it affects to HF wireless communications since the revision took effect. This research suggests some estimation methods with receivers, signal generators, or SINAD(Signal to Noise and Distortion) Meter which is so suitable for the RF environment that we can overcome the existing limit to the EMC environment. In addition, this research is focused on securing the environment for wireless communications by establishing the safety zone or suggesting the ways to prohibit the use of the bandwidth, which may cause serious interference, in order to minimize the effect of PLC on HF maritime mobile telecommunications.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.90-97
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• 2017

Construction of urban emergency shelters based on disaster-prevention green space is an important part of an urban disaster response plan. The accessibility of disaster-prevention green space is directly related to the disaster prevention service effect of green space. Taking the Jung-gu and Nam-gu districts of Ulsan city as research targets, the accessibility of three green spaces was analyzed by a network analysis method based on information regarding the distribution of population and green space and the urban road network. Two indicators for evaluating the service effect of green spaces were service population rate and service area rate. The results showed that the accessibility of the emergency refuge parks (5min) and central refuge parks was relatively good but the service area rate and service population rate of the emergency refuge parks (3min) and temporary refuge parks was less than 60%. In view of the overall situation, the service effect of disaster-prevention green space is at this point only general in Ulsan and there is great room for improvement.

• Polymer(Korea)
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• v.35 no.3
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• pp.203-209
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• 2011

Two smooth and textured surfaced HDPE geomembranes (GMs) were cut into dumbbell shape and notched where depth of the notch produced a ligament thickness of 10% to 90% of the nominal thickness with the specimen at 10% interval. A series of laboratory simulation test for installation damage were carried out at different loading cycles on HDPE GMs in accordance with ISO 10722 test method and the effect of number of loading cycle on installation damage was compared. It was found that yield stress and elongation at yield point decreased gradually as the notch depth was increased. Both installation damaged and notched, GMs were used to understand stress crack behavior and this behavior was observed through NCTL test at $50{\pm}1^{\circ}C$ at different yield stresses immerging in pH 4 and pH 12 buffer solutions. Over 35% tensile load, GMs became vulnerable to stress cracking. Both damaged and notched GMs showed the same trend. Especially, notched GMs showed less strength than installation damaged GMs at every stress cracking test condition.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.1
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• pp.154-178
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• 1999

Psoriasis is the recurrent disease of skin and till now its mechanism, pathogenesis and treatment are not clearly discovered. So, like these papers, we must investigate more safety and effective treatment of psoriasis. And I obtained the following condusions from the Oriental and Occidental bibliographic investigation. 1. In Oriental medicine. Baikbi, Pungsun, Eunselbyong, Songpisun, Baikselpung were the other names of Psoriasis. 2. In Occidental medicine, genetic factors, aggravation and inducible factors, biochemical factors, immunologic factors, disorder of epidermal kinetics, vascular malformation of dermis were cosidered to the pathogenic factors of psoriasis. 3. In Oriental medicine, the pathogenic factors of psoriasis were divided two parts. One is exogenous pathogenic factors which including the blood-heat, blood dryness, blood stasis, deficiency of liver and kidney, inharmony of impulsive and appointed pulsation, deficiency of blood. The other is exogenous pathogenic factors which including the wind-evil, wind-wetness, wind-heat, wind-cold, wetness-heat, cold-wetness, heat-evil. 4. In Occidental medicine, external applicative medicine, internal medicine, ultraviolet therapy, ultraviolet - external applicative medicine compound therapy and etc. were used the therapy of psoriasis. 5. In Oriental medicine, clean away heat and cooling blood, aliment the blood and moisturize, activating blood and expelling blood stasis, harmonize and invigorate the liver and kidney, invigorate the kidney, aliment the blood and moisturize the skin, aliment the blood and expelling the wind, expelling the wind and wetness, clean away heat and expelling wind, expelling the wind and scatter the cold, clean away heat and expelling the wetness, heat up the meridian and scatter the cold, clean away heat and remove the toxin and etc. were used the method of internal therapy of psoriasis. 6. Until Qing dynasty, wind expelling effective prescriptions like Bangpungtongsungsan, Sopungsan. Supungsunkisan and etc. were used and recently Yanghyelgeupungtang, Hwalhyelgeupungtang, Samultanggagam and etc. were used the internal therapy of psoriasis. 7. In the external therapy of psoriasis, Yuhonggo, Pungyugo, Sekryupiyeongo were used the plaster therapy and Folium Rerillae, Camphora, Fructus, Xanthii, Herba Spirodelae compound prescription were used the cleansing therapy, Okgisan, Chiunsan, Galmyogo, Hobunsan, Muisan, Madugo, Jeyugohengin were used the rubbing skin therapy. Rangdok Radix Aconiti, Bijeonilchoalkwang were used the attaching therapy, the extract of Rhizoma Et Radix Veratri was used the spreading pouder therapy. 8. In the acupuncture therapy of psoriasis, the Jelgol, chok Samni(S36), Kansa(P5), Haegye(S41), Wijung(B40) and etc. were used the acupuncture point, and the angle of helix incision threapy that disinfect and cut the angle of helix and plaster the Semen Glycine and Squama Manitis were used.

• Journal of Korea Water Resources Association
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• v.43 no.8
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• pp.695-707
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• 2010

The frequency and size of typhoon and local severe rainfall are increasing due to the climate change and the damage also increasing from typhoon and severe rainfall. The flood forecasting and warning system to reduce the damage from typhoon and severe rainfall needs forecasted rainfall using radar data and short-term rainfall forecasting model. For this reason, this study examined the applicability of short-term rainfall forecast using translation model with weather radar data to point out that the utilization of flood forecasting in Korea. This study estimated the radar rainfall using Least-square fitting method and estimated rainfall was used as initial field of translation model. The translation model have verified accuracy of forecasted radar rainfall through the comparison of forecasted radar rainfall and observed rainfall quantitatively and qualitatively. Almost case studies showed that accuracy is over 0.6 within 4 hours leading time and mean of correlation coefficient is over 0.5 within 1 hours leading time in Kwanak and Jindo radar site. And, as the increasing the leading time, the forecast accuracy of precipitation decreased. The results of the calculated Mean Area Precipitation (MAP) showed forecast rainfall tend to be underestimated than observed rainfall but the correlation coefficient more than 0.5. Therefore it showed that translation model could be accurately predicted the rainfall relatively. The present results indicate that possibility of translation model application of Korea just within 2 hours leading forecasted rainfall.