• Journal of the Korean Institute of Gas
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• v.26 no.4
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• pp.41-57
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• 2022

The global demand for carbon neutrality in response to climate change is in a situation where it is necessary to prepare countermeasures for carbon trade barriers for some countries, including Korea, which is classified as an export-led economic structure and greenhouse gas exporter. Therefore, digital transformation, which is one of the predictable ways for the carbon-neutral transition model to be applied, should be introduced early. By applying digital technology to industrial gas manufacturing facilities used in one of the major industries, high-tech manufacturing industry, and hydrogen gas facilities, which are emerging as eco-friendly energy, abnormal detection, and diagnosis services are provided with cloud-based predictive diagnosis monitoring technology including operating knowledge. Here are the trends. Small and medium-sized companies that are in the blind spot of carbon-neutral implementation by confirming the direction of abnormal diagnosis predictive monitoring through optimization, augmented reality technology, IoT and AI knowledge inference, etc., rather than simply monitoring real-time facility status It can be seen that it is possible to disseminate technologies such as consensus knowledge in the engineering domain and predictive diagnostic monitoring that match the economic feasibility and efficiency of the technology. It is hoped that it will be used as a way to seek countermeasures against carbon emission trade barriers based on the highest level of ICT technology.

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.85-107
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• 2022

This study is to analyze the induced effect, network connectivity, and network visualization of the water transportation industry on the overall economy in relation to all industries. For this, various inducement coefficients of the water transportation industry are analyzed using industry linkage analysis and unit structure matrix, and network visualization analysis is performed using network connectivity and NetDraw using Ucinet 6 that utilizes unit structure matrix and inverse matrix function. As a result of the study, analysis results of input coefficient, production inducement coefficient, value-added inducement coefficient, and inter-industry chain effect were presented as various inducement coefficients in the water transportation industry. content was presented. Through this study, the current position and status of the water transportation industry and its relationship with all industries were confirmed, and the strategic relationship with which industries it should be presented was presented. In the future, it is necessary to further analyze the current status and trends of various induced effects, connectivity (centrality), and network visualization analysis using industry-related analysis published since the 2000s.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.18-18
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• 2020

금강하구와 같이 막힌 대형 하구는 근본적으로 복잡한 물리화학적 프로세스와 다양한 이해당사자간의 갈등 때문에 단편적인 접근으로는 관리의 한계가 있을 수밖에 없는 환경이다. 더욱이 하굿둑의 갑문을 열어 하구순환을 복원하는 해수유통 사업은 그 자체가 가지는 환경적 효용성의 확인과 기존 용수이용 체계의 전면적 변화와 관련된 상당한 비용이 요구된다는 면에서 특별한 논란이 되어왔다. 본 연구는 해수유통으로 인한 금강 하구해역의 수리, 수질, 퇴적 및 생태 등 다양한 환경적 변화를 집중적인 현장 조사 및 통합 모델링을 통해 정량적으로 예측하고 이를 지역 이해당사자 논의 체계인 금강하구해역정책협의회에 제공함으로써 해수유통과 연관된 이해당사자 간 갈등을 완화하고 과학적 자료에 근거한 정책결정을 지원하기 위해 수행되었다(과학-정책의 통합). 조사연구는 하굿둑 갑문 개방에 따른 다양한 시나리오별로 해수유통으로 인한 영향을 하구해역(하굿둑의 바다 쪽 해역)과 하구호(하굿둑의 하천 쪽 담수역)에 미치는 영향을 검토하였다(하천-하구호-연안해역의 공간적 통합). 시나리오는 하구해역정책협의회의 요구사항을 반영하여 개발되었고, 시나리오별 영향파악은 수리(조석 및 파랑 포함), 퇴적물 이동 및 수질은 Delft3D모델을, 유역으로부터의 유량 및 오염물질 부하량은 분포형 비점모델인 STREAM을, 김양식과 이매패류 생산량을 추정하는 생태모델은 통계기반의 포인트 모델을 통해 이루어졌다(수리-퇴적-수질-생태계 모델의 통합). 시나리오 분석결과, 상시 해수유통을 제외한 대부분의 하굿둑 부분 개방 시나리오에서는 하구해역에 미치는 영향이 제한적으로 나타나는 것으로 예측되었다. 이는 하굿둑 부분 개방에 따른 담수방류량 및 이에 대응하는 해수의 유동패턴이 현재와 크게 달라지지 않음을 반영한다. 반면 하구호에 대한 영향은 하구해역에 비해 하굿둑 갑문 운영시나리오에 따라 상대적으로 민감하게 변화되는 것으로 예측되었다. 갑문의 부분 개방을 통해 하구호의 수위를 현재 대비 5cm~50cm 변화시켰을 때 1psu 염분의 저층에서의 침투거리는 하굿둑 상류 6km~18km 정도로 예측되었고 갑문 개방에 의해 염분 침투 거리의 조절이 가능할 것으로 나타났다. 단, 사용된 통합모델은 수년간의 검보정 과정을 반복적으로 수행하여 예측의 정확도를 지속적으로 개선하였지만, 모델운영 자체의 불확실성을 고려할 때 실제 해수유통을 위해서는 시범개방을 통해 모델 예측의 결과를 확인할 필요가 있다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.26 no.2
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• pp.91-111
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• 2024

Most of utility cable tunnels are constructed utilizing shield TBM as part of the underground transmission line project. The TBM chamber is the only space inside the tunnel that encounters rock and soil, and is the place with the highest frequency of accident exposure, such as collapse and collision accidents. Since there is currently no way to measure the disc cutter wear from outside the chamber, frequent inspection by workers is essential. Accordingly, in this study, in order to prevent safety accidents inside the TBM chamber and expect the effect of shortening the construction period by reducing the number of chamber openings, the concept of disk cutter wear measurement technology was established and a prototype was produced. By considering prior technology and determining that magnetic sensors are most suitable for the excavation environment, wear measurement sensor package were developed integrating magnetic sensors, wireless communication modules, power supply, external casing, and monitoring systems. To verify the performance of the prototype in an actual excavation environment, a full-scale tunnelling test was performed using a 3.6 m EPB shield TBM. Based on the full-scale tests, five prototypes were operated normally among eight prototypes. It was analyzed that sensor measurement, wireless communication, and durability performance were secured within a maximum thrust of 3,000 kN and a rotation speed of 1.5 RPM.

• Journal of Environmental Health Sciences
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• v.50 no.2
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• pp.146-156
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• 2024

Background: Children who use playground facilities are exposed to potential risks due to the high concentration of heavy metals contained in the finishing materials of facilities in children's playgrounds. Objectives: The purpose of this study was to investigate the concentration of heavy metals in the finishing materials of outdoor children's playgrounds where harmful heavy metals exist in Gwangju and to conduct human risk assessment for children and adults by age to find the risks and limitations. Methods: The bottom and top layers of double-painted paint were peeled off and collected together from the finishing materials of children's play facilities such as slides, swings, and seesaws in 147 children's parks in Gwangju. Heavy metals were analyzed using ICP-OES, etc., and human risk assessment was performed using the concentrations of heavy metals. Results: Based on 1.0E-04, which requires legal regulation, CTE was found to pose a carcinogenic risk for preschool children and no carcinogenic risk for the rest of the age groups. However, RME showed that both men and women of all ages had a carcinogenic risk. For reference, when the carcinogenic risk was based on 1.0E-06, CTE was found to pose a carcinogenic risk from infants to elementary school students, and RME was found to have a carcinogenic risk in all age groups. It was judged that there is a non-carcinogenic risk if the non-carcinogenic risk exceeds 1 based on the hazard index (HI) 1. In CTE, there was no non-carcinogenic risk, and RME for preschooler males (1.49E+00) and females (1.56E+00) were found to have non-carcinogenic risk. Conclusions: This study was meaningful in that it examines the differences in the current management of heavy metals concentration standards and potential carcinogenic and non-carcinogenic risks to the human body and discusses the relationship between heavy metals and human health effects.

• Environmental and Resource Economics Review
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• v.14 no.4
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• pp.817-838
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• 2005

In this paper, the resource adequacy as well as the optimum fuel mix is obtained by the following procedures. First, the regulation body, the government agency, determine the reliability index as well as the optimum portfolio of the fuel mix during the planning horizon. Here, the resources with the characteristics of public goods such as demand-side management, renewable resources are assigned in advance. Also, the optimum portfolio is determined by reflecting the economics, environmental characteristics, public acceptance, regional supply and demand, etc. Second, the government announces the required amount of each fuel-type new resources during the planning horizon and the market participants bid to the government based on their own estimated fixed cost. Here, the government announces the winners of the each auction by plant type and the guaranteed fixed cost is determined by the marginal auction price by plant type. Third, the energy market is run and the surplus of each plant except their cost (guaranteed fixed cost and operating cost) is withdrew by the regulatory body. Here, to induce the generators to reduce their operating cost some incentives for each generator is given based on their performance. The performance is determined by the mechanism of the performance-based regulation (PBR). Here the free-riding performance should be subtracted to guarantee the transparent competition. Although the suggested mechanism looks like very regulated one, it provides two mechanism of the competition. That is, one is in the resource construction auction and the other is in the energy spot market. Also the advantages of the proposed method are it guarantee the proper resource adequacy as well as the desired fuel mix. However, this mechanism should be sustained during the transient period of the deregulation only. Therefore, generation resource planning procedure and market mechanisms are suggested to minimize possible stranded costs.

• Journal of Mushroom
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• v.7 no.3
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• pp.122-129
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• 2009

We determined the genetic relatedness among 81 commercial varieties of oyster mushrooms by either comparison of fruiting body characteristics or using PCR amplification with URP primers. Also, we assessed their temperature adaptation by using box cultivation. Based on our data, some varieties such as Wonhyung and variety 1, Suhan and variety 20, Wang-hukpyung and variety 4, Chunchu #2 and variety 6, Shinong #11 and variety 1, Samgu #1 and variety 2, showed the close genetic relatedness between each other. It is known that mushroom culture room is affected by outer temperature because mushroom need the adequate aeration for their growth. Therefore, in aspect of saving energy, the cultivation of season favorable mushroom species has been recommended. Eight different commercial varieties including Sa-chul, Yeoreum and Bunhong(Pink) grew well at high temperature ($16^{\circ}C$). Also, about 51 different oyster mushroom strains were good at relatively high temperature. However, other 64 different oyster mushroom varieties were grew well at low temperature ($11^{\circ}C$). Fourty-nine varieties were adapted well in most temperatures. The slow growth rate were observed in some varieties including Kun(P. eryngii ), Awi(P. nebrodensis ), and Cheunbok(P. abalonus ), which are not suitable for box cultivation. We believe that the culture characterization of each mushroom varieties should help many farmers in many aspects such as saving energy, quantity improvement and new variety development etc.

• Journal of Nutrition and Health
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• v.42 no.1
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• pp.23-37
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• 2009

The purpose of this study was to investigate the health status of preschool children using the questionnaires about dietary behaviors and anthropometric indices. And also nutritional status was investigated using questionnaires for 24-hr recall method. The study was conducted in 145 children aged 3 to 6 years and questionnaires for dietary behaviors and dietary intakes were performed by mothers of children in Ulsan. Just nine percent of children were graded as good in terms of having healthy eating habits, this means that the nutrition education for the dietary behaviors should be more focused on preschool children. With regard to the frequency of food intake, children consumed green & yellow vegetables less frequently, meanwhile consumed high protein source food (meat, egg and bean) and milk and its product more frequently. Children almost never consumed fried foods as often as 1-2 times a weak. In assessment of the health status, children have the highest prevalence of colds and allergy, but lower prevalence of clinical symptoms due to the nutritional deficiency. The mean height was $103.6\;{\pm}\;6.4\;cm$ and significantly different among age (p < 0.05), but was not significantly different between sex. The mean weight was $17.8\;{\pm}\;3.0\;kg$ and significantly different in 5, 6years old among age. By the WLI criteria, 11.1% of children were underweight and 17.4% of children were overweight or obese. By the Rohrer index criteria, any children were not underweight and 86.8% of children were overweight or obese. By the Kaup index criteria, 2.8% of children were underweight and 29.2% of children were overweight or obese. And Obesity Index criteria, 2.1% of children were underweight and 20.8% of children were overweight or obese. The results of obesity rate by all criteria except Rohrer index indicated similar level, were significantly high in age 3 with all criteria, and decreased with age increased. The energy intake of children was lower than EER (Estimated Energy Requirements) of Dietary Reference Intakes for Koreans (KDRIs) by as much as 85.7%. Acceptable Macronutrient Distribution Ranges (AMDR) was 62.6:21.5:15.7 as carbohydrate:protein:lipid, so children consumed protein more, but consumed lipid less compared with those of KDRIs. Vitamin A intake was 133% of recommended intakes (RI) and calcium intake which was identified as the nutrient most likely to be lacking in diets was 98.9% of RI. The intakes of all minerals and vitamins except folate were higher than KDRIs. 33.3% of children were distributed in insufficiency of energy intake, 42.7% of children were distributed in insufficiency of lipid intake. These results indicate that the need of developing of nutrition education program and further concern of a public health center, university and children care center about dietary life for preschool children.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.339-348
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• 2004

This study was peformed to assess the relationships among bone mineral density (BMD), Physiological characteristics and lifestyle factors in 61 premenopausal working women aged 30∼49 y in Busan. The BMDs of the lumbar spines (Ll∼L4), femoral necks (FN), ward's triangles (WT) and trochanters (TC) were measured by dual energy X-ray absorptiometry. Data for physiological characteristics and physical activity was assessed by questionnaire and usual intakes of coffee, green tea, alcohol, Coca cola by food frequency questionnaire. The BMDs of L14, FN, WT and TC were 1.02 g/$\textrm{cm}^2$, 0.76 g/$\textrm{cm}^2$,0.69 g/$\textrm{cm}^2$ and 0.66 g/$\textrm{cm}^2$respectively The BMD of FN was assessed as osteopenia by T-score. The BMD of WT was positively correlated with age of monarch (p<0.05) and the BMD of Ll4 was positively correlated with delivery number (p<0.05). The BMD of Ll4 was positively correlated with hours of outdoor activity per weekend and week (p<0.05, p<0.05). The BMDs of FN and WT (p<0.05, p<0.05) were positively correlated with intake of green tea per month and the BMD of FN (p<0.05) was positively correlated with intake of wine per month. But the BMD of Ll (p<0.05) was negatively correlated with intake of Coca cola per month. So nutritional education for increasing hours of outdoor activity and decreasing intake frequency of beverage contributing to diminishment of bone mineral density is needed for premenopausal working women to prevent osteoporosis.

• Journal of Nutrition and Health
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• v.42 no.1
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• pp.38-47
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• 2009

The purpose of the study was to develop an eating habit checklist for screening elementary school children at risk of inadequate micronutrient intake. Eating habits, food intake, and anthropometric data were collected from 142 children (80 boys and 62 girls) in the $4^{th}$ to $6^{th}$ grades of elementary schools. Percentage of Recommended Intakes (RI) and Mean Adequacy Ratio (MAR) of six micronutrients; vitamin A, riboflavin, vitamin C, calcium, iron, zinc, and the number of nutrients the children consumed below EAR among the six nutrients were used as indices to detect the risk of inadequate micronutrient intake. Pearson correlation coefficients were calculated between eating habit scores and inadequate micronutrient intake indices in order to select questions included in the checklist. Meal frequency, enough time for breakfast, regularity of dinner, appetite, eating frequencies of Kimchi, milk, fruits and beans showed significant correlations with indices of inadequate micronutrient intake. Stepwise regression analysis was performed to give each item a different weight by prediction strength. To determine the cut-off point of the test score, sensitivity, specificity, and positive predictive values were calculated. The 8-item checklist with test results from 0 to 12 points was developed, and those with equal or higher than 6 points were diagnosed as high-risk group of inadequate micronutrient intake, and those with 4 or 5 points were diagnosed as moderate-risk group. Among our subjects 14.1% was diagnosed as high-risk group, and 30.3% as moderate-risk group. The proportions of the subjects who consumed below EAR of all micronutrients but vitamin C were highest in the high-risk group, and there were significant differences in the proportions of the subjects with intake below EAR of all micronutrients except vitamin B6 among the three groups. This checklist will provide a useful screening tool to identify children at risk of inadequate micronutrient intake.