• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.511-525
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• 1995

To elucidate some DNA adducts as a biological marker for workers of chromate pigment, the effects of chromium exposure on the formation of 8-hydroxydeoxyguanosine(8-OH-dG) and sister chromatid exchanges(SCEs) frequency in 38 workers of a pigment plant in Bucheon which utilized lead chromates, were examined. The chromium contents of venous blood and urine were measured as working environmental exposure level. The concentrations of 8-OH-dG in DNA isolated from lymphocytes were determined with high performance liquid chromatography and electrochemical detector and denoted as a molar ratio of 8-OH-dG to deoxyguanosine(dG). The SCEs frequency were analyzed in DNA isolated from lymphocytes. A significant correlation was found between creatinine adjusted urine chromium concentration and the molar ratio of 8-OH-dG to dG(r=0.47, p<0.01). After adjusting the current smoking habit, the correlation coefficient was increased(r=0.62, p<0.05). However, there was no significant correlation between the SCE frequency and chromium exposure. This significant results between molar ratio of 8-OH-dG to dG and chromium exposure are in good agreement with in vitro studies that support the importance of DNA adduct formation for the carcinogenic effect of chromium.

• Analytical Science and Technology
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• v.23 no.1
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• pp.1-14
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• 2010

It is of importance that all countries in worldwide, including EU and China, have adopted the Restrictions on the use of certain Hazardous Substances (RoHS) for all electronics. IEC62321 document, which was published by the International Electronics Committee (IEC) can have conflicts with the standards in the market. On the contrary Publicly Accessible Specification (PAS) for sampling published by IEC TC111 can be adopted for complementary application. In this work, we tried to find a route to disassemble and disjoint cellular phone sample, based on PAS and compare the screening methods available in the market. For this work, the cellular phone produced in 2001, before the regulation was born, was chosen for better detection. Although X-ray Fluorescence (XRF) showed excellent performance for screening, fast and easy handling, it can give information on the surface, not the bulk, and have some limitations due to significant matrix interference and lack of variety of standards for quantification. It means that screening with XRF sometimes requires supplementary tool. There are several techniques available in the market of analytical instruments. Laser ablation (LA) ICP-MS, energy dispersive (ED) XRF and scanning electron microscope (SEM)-energy dispersive X-ray (EDX) were demonstrated for screening a cellular phone. For quantitative determination, graphite furnace atomic absorption spectrometry (GF-AAS) was employed. Experimental results for Pb in a battery showed large difference in analytical results in between XRF and GF-AAS, i.e., 0.92% and 5.67%, respectively. In addition, the standard deviation of XRF was extremely large in the range of 23-168%, compared with that in the range of 1.9-92.3% for LA-ICP-MS. In conclusion, GF-AAS was required for quantitative analysis although EDX was used for screening. In this work, it was proved that LA-ICP-MS can be used as a screening method for fast analysis to determine hazardous elements in electrical products.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2465-2472
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• 2014

Background: The American Joint Committee on Cancer (AJCC) published a new staging system ($7^{th}$ edition) in 2009. In our study, we evaluated the survival results and prognostic factors among T4 local advanced non-small cell lung cancer (LA-NSCLC) patients in a large heterogeneous group, in accordance with this new system. Materials and Methods: We retrospectively evaluated the files of 122 T4 N0-3 M0 LA-NSCLC patients, identified according to the new staging system, treated at two centers between November 2003 and June 2012. Variables correlating with univariate survival at p<0.20 were later included in multivariate Cox regression analysis. Here, selection of relevant predictors of survival was carried out in accordance with the likelihood ratio formula with p<0.05 regarded as significant. Results: The median age was 60 and the median follow-up period was 17.4 months. Median overall survival (OS) was 18.3 months, the 1 year overall survival (OS) rate was 72%, and the 5 year OS rate was 28%. Statistically significant predictors of survival were (p<0.20) ECOG-PS (Eastern Cooperative Oncology Group Performance Status), age, T4 factor subgroup, stage and primary treatment in OS univariate analysis. On multivariate analysis for OS ECOG-PS (p=0.001), diagnostic stage (p=0.021), and primary treatment (p=0.004) were significant. In the group receiving non-curative treatment, the median OS was 11.0 months, while it was 19.0 months in the definitive RT group and 26.6 months in the curative treatment group. There was a significant difference between the non-curative group and the groups which had definitive RT and curative operations (respectively p<0.001 and p=0.001) in terms of OS, but not between the groups which had definitive RT and curative operations. The median event free survival (EFS) rate was 9.9 months, with rates of 46% and 19% at 3 and 5 years, respectively. On univariate analysis of EFS rate with ECOG-PS, weight loss and staging, statistical significance was found only for thorax computerized tomography (CT)+18F-fluorodeoxy-glucose positron emission tomography-CT (PET-CT) use, stage and primary treatment (p<0.20). In multivariate analysis with EFS, only the primary treatment was statistically significant (p=0.001). In the group receiving non-curative treatment, the median EFS was 10.5 months while in the curative operation group it was 14.7 months. When all the primary treatment groups were taken into consideration, grade III/IV side effect swas observed in 57 patients (46.6%). Esophagitis was most prominent among those that received definitive radiotherapy. Conclusions: Independent prognostic factors among these 122 heterogeneous LA-NSCLC T4 N0-3 M0 patients were age at diagnosis, ECOG-PS, stage and primary treatment, the last also being a significant prognostic indicator of EFS. Our findings point to the importance of appropriate staging and a multidisciplinary approach with modern imaging methods in this patient group. In those with T4 lesions, treatment selection and the effective use of curative potential should be the most important goal of clinical care.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.73-84
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• 2018

Recently, the importance of flame retardation treatment technology has been emphasized due to the increase in urban fire accidents and fire damage incidents caused by building exterior materials. Particularly, in the utilization of wood-based building materials, the flame retarding treatment technology is more importantly evaluated. An Intumescent system is one of the non-halogen flame retardant treatment technologies and is a system that realizes flame retardancy through foaming and carbonization layer formation. To apply the Intumescent system, composite material was prepared by using Ethylene vinyl acetate (EVA) as a matrix. To enhance the flame retardant properties of the Intumescent system, a nano-clay was applied together. Composite materials with Intumescent system and nano - clay technology were processed into sheet - like test specimens, and then a new structure of cross laminated timber with improved flame retardant properties was fabricated. In the evaluation of combustion characteristics of composite materials using Intumescent system, it was confirmed that the maximum heat emission was reduced efficiently. Depending on the structure attached to the surface, the CLT had two stages of combustion. Also, it was confirmed that the maximum calorific value decreased significantly during the deep burning process. These characteristics are expected to have a delayed combustion diffusion effect in the combustion process of CLT. In order to improve the performance, the flame retardation treatment technique for the surface veneer and the optimization technique of the application of the composite material are required. It is expected that it will be possible to develop a CLT structure with improved fire characteristics.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.54-65
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• 2017

The purpose of this study is to investigate the perception of landscape law and institutions and to provide basic data for improvement of landscape systems. Specifically, we analyzed the importance and achievement of various landscape systems, and examined the understanding and perception of government officers in landscape plan, landscape project, landscape agreement, landscape reviews and landscape committees, landscape ordinance, and landscape administration. The main results of the study are summarized as follows. 1. Overall, the landscape administration system was highly interested, and it was also positive about the utility of the landscape law and the landscape charter. As a result of analysis of the IPA, the landscape plan and the landscape policy plan need to be intensively improved. 2. The landscape plan is mostly used for the purpose of responding to the scenery review or complaint request, but about 10.8% of respondents said that they did not refer it at all, so it is urgent to make the contents of the landscape plan real and improve the performance. Although many officers thought that less than 18 months would be quite enough for landscape plans, but it is necessary to change this duration issue. 3. In order to improve landscape projects and landscape agreements, it seems that budget securing, experts, and promotional organizations should be improved first. 4. It is urgently necessary to enhance the understanding about overall landscape law and systems of landscape review committee in order to supplement the landscape review and the landscape committee. 5. Administrative support such as personnel recruitment is required for landscape ordinance and landscape administration, and it is also found that many officers also have a great burden in making subjective judgment as the person in charge. There could be a positive bias in the results of the study, because the survey was conducted only for public officials who participated in the education. But the result will be helpful to look at the overall tendency of the landscape system. I hope that it will help improve the landscape system in the future much more realistic.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.410-416
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• 2016

After the Sewol Ferry accident, the importance of maritime safety has been emphasized in Korea. In particular, educational and experience training are not only being conducted for maritime personnel but also in schools and at maritime-related organizations in order to broadly instill maritime safety awareness. Based on SOLAS regulations, safety education for sailors conducted every 10 days passenger boats, and fire-fighting drills and abandon-ship training should be conducted once a month on merchant ships. After the Sewol Ferry accident, the maximum number of trainees was reduced from 40 to 20 in order to improve the effectiveness of these training sessions by requiring all trainees to participate in the actual training. The current training process consists of two steps: textbook-based theoretical training and actual practice. Current training environment provides limited capability from human and facility recourses which limit the numbers of trainee participated and system operation time. By introducing the simulation training, it will improve the trainee skill and performance prior to the on-site training and allow the more effective and rapid progress on actual practice. Therefore, it will be proposed the three-step training method in order to improve the effectiveness on fire-fighting drill in Maritime Safety Education on this study. This study suggests a three step training method that would increase the efficiency of maritime safety education. An image-training step to enhance individual task awareness and equipment usage via simulation techniques after theoretical training has been added. To implement this simulation, a virtual training session will be conducted before actual training, based on knowledge obtained from theoretical training, which is expected to increase the speed with which trainees can adapt during the practical training session. In addition, due to the characteristics of the simulation, repeated training is possible for reaction drills in emergency circumstances and other various scenarios that are difficult to replicate in actual training. The efficiency of training is expected to improve because trainees will have practiced before practical training takes place, which will decrease the time needed for practical training and increase the number of training sessions that can be executed, increasing the efficiency of training overall. This study considers development methods for fire-fighting drill simulations using virtual reality techniques.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.8-9
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• 2017

Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.96-106
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• 2013

The aim of this study was to reveal the advantages and disadvantages of Terelj Mongolian National Park based on the impressions of foreign and domestic travelers, and subsequently suggest supporting ideas to make this tourist attraction more enjoyable for travelers. A statistical program(SPSS 20.0) and an IPA matrix method were used to reveal the impressions of travelers and the results showed the following ideas. First, we made the technical analyses to demonstrate the characteristics of the current natural scenery which travelers want to see and the results indicated that both Korean and Mongolian travelers overall were not satisfied and the Park was not as they had imagined. The second part of the research highlighted the differences between the impressions held by Mongolian and Korean travelers, which showed dissimilarities in cultural resources, food, variety of events, cultural functions and parking, all of which were shown as important criteria in sightseeing. The variations were found in scenes of nature, variety of programs, and food, areas which revealed and were very important in the overall satisfaction of travelers. Third, the IPA method was used for analyze the advantages and disadvantages of Terelj National Park. The Mongolian travelers nominated the width of the road, cleanliness, variety of events and parking are the most essential things to feel satisfied, but Koreans selected safety of travel, accommodation, the width of the road and cleanliness. Finally, we analyzed the feelings of the travelers at the end of their trip. The Mongolian travelers preferred the area resource and environment convenience to feel satisfaction. For Korean travelers, the area resource is the most important when choosing travelling sights. Based on these results, if we take responsibility to protect the beauty of nature, and create a sightseeing place using natural sources, while also making more comfortable accommodations and improving the services, it can be a more unique place than others and lead to greater overall satisfaction for travelers.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.211-220
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• 1994

The critical need of forest road for enchanting the additional values of various forest products, in addition, giving more recreational opportunity to citizen, has been recognized. In this study the present author aimed to ascertain the most effective construction working plan of forest road being tit to Korean geographic condition. To execute this research program, four locations in national forest of Kangweon-do district and other four locations in private forest in Chollabuk-do district both where forest roads have previously been constructed were selected to analyze the effectiveness basing upon the various factors separately or in combination. The results are summarized as follows ; 1. The investment efficiency in forest road construction showed to increase in the area where terrain factors and district social factors rate is high, and to decrease in the area where forest status factors and forest road structure factors rate is high. So in future the Forest Resource Development Model of forest road should take more importance particularly on those area having terrain factor ratio is low. The extractable value of constructed forest road based on forest status factors rate is expected to increase in case of high considerably. 2. To construct of forest road for increasing multiple use of forests, forest road should be construct with priority on area where obtained total score by evaluation factors is high. And these evaluation factors should take possible determine the position of forest road construction. 3. The following five types of forest road basing upon function performance are suggested with regard to the place where road is constructed. (1) Forest Utilization Model ; where forest status factors and forest road structure factors rate are over 60%. (2) Forest Resource Development Model ; where terrain factors, forest status factors, forest road structure factors and district social factors rate are less than 60%. (3) Community Development Model ; where terrain factors, forest road structure factors and district social factors rate are over 60% but forest status factors rate are less than 60%. (4) Recreation and Health Model ; where terrain factors, forest status factors, forest road structure factors and district social factors rate are over 60%. (5) Multiple Use Model ; where both forest status factors and district social factors rate are over 60%.

• Journal of Distribution Research
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• v.17 no.3
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• pp.59-92
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• 2012

With accumulated research evidence, there is little doubt that leadership behavior is related to a wide variety of positive individual and organizational outcomes. Indeed, leadership behavior has been empirically linked to increased employee satisfaction, organizational commitment, extra effort, turnover intention, organizational citizenship behavior, and overall employee performance. Although leadership behavior has been linked to a number of positive organizational outcomes, research regarding the antecedents of such behavior is limited. Especially there is little research dealing with the antecedents of inter-organizational leadership behavior. This study interests in inter-organizational ethical leadership among marketing channel members. In both the mass media and the academic association, there has been a surge in interest in the ethical and unethical behavior of leaders. Although the corporate scandals in recent years may explain much of the mass media and popular focus, academics' interest has been limited by evidence that ethical leadership behavior is associated with both positive and negative inter-organizational processes and performances. This study tried to contribute to this body of knowledge by examining antecedents of ethical leadership. Ethical leadership is defined "the demonstration of normatively appropriate conduct through personal actions and interpersonal relationships, and the promotion of such conduct to followers through two-way communication, reinforcement, and decision-making." Ethical leaders not only inform individuals of the behefits of ethical behavior and the cost of inappropriate behavior, such leaders also set clear standards and use rewards and fair and balanced punishment to hold followers accountable for their ethical conduct. Despite the assume importance and prominence of ethical leadership among organizations, there are still many questions relating to its antecedents and consequences. One is whether the likelihood of an leading organization being perceived as an ethical leader among other following organizations in marketing channels can be predicted using its characteristics and inter-organizational relationship maintenance skills. Identifying trait and skill antecedents will aid in the development of strategies for selecting and developing ethical leaders and determining the best means to reinforce ethical behaviors. The purpose of this study is to investigate the effects of three categorized variables on ethical leadership of channel leader. To be concrete, this study develops a model of the antecedents of three conceptually distinct forms of channel leader characteristics, such as organizational traits, inter-organizational relationship maintenance strategies, and supplier management strategies, and tests the hypothesized differential effects on ethical leadership of marketing channel leaders. The reason why this study deals with discount store channel is that there is very strong inter-dependence between a discount store and its suppliers. Their strong inter-dependence makes their relationship as the relationship between a leader and suppliers and creates an atmosphere that leadership occur without difficulty. The research model is as follows. For the purpose of empirical testing, 295 respondents of suppliers of discount store channel in Korea were surveyed. The procedures included scale reliability, and discriminant and convergent validity were used to validate measures. Also, the reliability measurements traditionally employed, such as the Cronbach's alpha, were used. All the reliabilities were greater than .70. This study conducted confirmatory factor analyses to assess the validity of our measurements. All items loaded significantly on their respective constructs(with the lowest t-value being 15.2), providing support for convergent validity. We then examined composite reliability and average variance extracted(AVE). The composite reliability of each construct was greater than .70. The AVE of each construct was greater than .50. This study tested research model using Partial Least Square(PLS). The estimation of the structural equation model revealed an acceptable fit of the model to the data($r^2$=.851). Thus, This study concluded that the model fit was considered acceptable. The results of PLS are as follows. The results indicated that conscientiousness, openness, conflict management, social networks, training, fair reward had positive effects on ethical leadership of channel leaders. On the other hand, emotional insecure had negative effect and agreeableness, assurance, and inter-organizational communication had no significant effect on supply chain leadership.