• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.4
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• pp.405-413
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• 2015

In the US, the number of cases of subterranean water contamination from tritium leaking through a damaged buried nuclear power plant pipe continues to increase, and the degradation of the buried metal piping is emerging as a major issue. A pipe blocked from corrosion and/or degradation can lead to loss of cooling capacity in safety-related piping resulting in critical issues related to the safety and integrity of nuclear power plant operation. The ASME Boiler and Pressure Vessel Codes Committee (BPVC) has recently approved Code Case N-755 that describes the requirements for the use of polyethylene (PE) pipe for the construction of Section III, Division 1 Class 3 buried piping systems for service water applications in nuclear power plants. This paper contains tensile and slow crack growth (SCG) test results for high-density polyethylene (HDPE) pipe welds under the environmental conditions of a nuclear power plant. Based on these tests, the fracture surface of the PENT specimen was analyzed, and the fracture mechanisms of each fracture area were determined. Finally, by using 3D finite element analysis, limit loads of HDPE related to premature failure were verified.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.205-216
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• 2007

South Korea is the representative consumption country of herbal medicines and most of herbal medicines circulating in Korea have been importing from the developing countries of Southeast Asia such as China, Vietnam, Indonesia and so forth. Domestic hygiene and safety are continuously proposed because herbal medicines which are circulating have the possibility could remain contaminants or residues. Physicochemical contaminants such as heavy metals, persistent organic pollutants, radionucleosides, microbial toxins, biological contaminants such as microorganisms and animals, agrochemical residues such as pesticides, substances used for fumigation, antiviral agents, and solvent residues are classified as major contaminants and residues in herbal medicines from 2005 September WHO.$^{1)}$ Currently our administration have established a permission standard and the inspection criteria against the heavy metal, the residual pesticides and a residual sulfur dioxide. Furthermore our administration is continuously monitoring and conducting researches for the policies and their scientific ground against herbal medicines. But the appearances or discoveries of the harmful new species due to environmental and industrial developments are becoming social problems. Therefore it may be necessary to continuously consider and investigate regarding hereupon. Recently, the contamination of the mycotoxins against foods such as cereals, nuts and the powdered red pepper have developed and started became problematic issue, and possibility of contamination against the herbal medicine is proposed. And since populations who are using the herbal medicines very limited to several nations, recognition and researches about contamination of mycotoxins in herbal medicines are very insufficient. Therefore it will be need to more focus on the international regulation of quality control and safety for herbal medicines. Now on, we are going to introduce the importance, occurrence, characteristic properties, World-wide research trends and detoxification of aflatoxins, which is known as the most potent mutagen, carcinogen and teratogen mycotoxins.

• Journal of Korean Society of Transportation
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• v.30 no.4
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• pp.21-32
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• 2012

Exclusive bus lane (EBL) is typically located in the roadway median, and is accessed by weaving across the GPLs(general purpose lanes) before entering from the left lane of the GPLs. To maximize the potential for successful EBL operations, a critical design issue that requires special attention is the length of bus weaving section before entering EBL. The process of developing guidelines for the length of bus weaving section can be supported by a sensitivity analysis of performance measure (safety) with respect to the bus weaving distance. However, field data are difficult to obtain due to inherent complexity in creating performance measure (safety) samples under various interesting flows and bus weaving distance that are keys to research success. In this paper, VISSIM simulation is applied to simulate the operation of roadway weaving areas with EBL, and based on vehicle trajectory data from microscopic traffic simulation models, the Surrogate Safety Assessment Model (SSAM) computes the number of surrogate conflicts (or degree of safety) with respect to the bus weaving distance. Then, a multiple linear regression (MLR) model using safety data (number of surrogate conflicts) is developed. Finally, guidelines for bus weaving distance are established based on the developed MLR. Developed guidelines explicitly indicate that a longer bus weaving distance is required to maintain desired safety as weaving volume increases.

• Environmental and Resource Economics Review
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• v.22 no.2
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• pp.367-391
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• 2013

After the Fukushima nuclear accident, the external costs of generating electricity from nuclear power plants such as additional safety compliance costs and possible accident risk action costs have gained increasing attention from the public, policy-makers and politicians. Consequently, estimates of the external costs of nuclear power are very deliberate issue that is at the center of the controversy in Korea. In this paper, we try to calculate the external costs associated with the safety of the nuclear power plants, particularly focusing on additional safety compliance costs and possible accident risk action costs. To estimate the possible accident risk action costs, we adopt the damages expectation approach that is very similar way from the external cost calculation of Japanese government after the Fukushima accident. In addition, to estimate additional safety compliance costs, we apply the levelized cost of generation method. Furthermore, we perform the sensitivity analysis to examine how much these social costs increase the electricity price rate. Estimation results of the additional security measure cost is 0.53Won/kWh ~ 0.80Won/kWh depending on the capacity factor, giving little change on the nuclear power generation cost. The estimates of possible accident risk action costs could be in the wide range depending on the different damages of the nuclear power accident, probability of the severe nuclear power accident and the capacity factor. The preliminary results show that it is 0.0025Won/kWh ~ 26.4188Won/kWh. After including those two external costs on the generation cost of a nuclear power plant, increasing rate of electricity price is 0.001%~10.0563% under the capacity factor from 70% to 90%. This paper tries to examine the external costs of nuclear power plants, so as to include it into the generation cost and the electricity price. This paper suggests one of the methodologies that we might internalize the nuclear power generations' external cost, including it into the internal generation cost.

• Archives of design research
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• v.19 no.3 s.65
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• pp.105-116
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• 2006

In product manufacturing industries, a recent issue is the green concept. The green concept is a complicated area. If the green concept is for products, its serious issues have to be criticized. Although the importance of the green concept has overflowed, its influences have not been disputed vigorously. So this study is to critic the serious issues of the green concept in aesthetics in product design, manufacturing, and products' prices. The green environment has four representative elements: systems, policies, minds, and technologies, but they are not in the field of design. An element of the green concept, green design is also a sub concept for design, so it should be based on aesthetics. It is green aesthetics. But since green design first appeared, it has never approached by aesthetics because it has mostly had social meanings and expectations. So for green aesthetics, to think about what makes a product, and what can be aesthetic issues among them are important. Products consist of form, structure, material, and technology. Form means different shapes in a structure, but there cannot be any specific directions for a green concept. Structure has two kinds: interior and exterior structure. While interior structure has a technological character, exterior structure is deeply related with aesthetics, but it has also no chance for green concept. Material can be divided as two also: aesthetic and technological. Aesthetics materials mean the colors, opacity, and tactile sense of materials, but they are not aesthetic issues. Technological materials are recycled materials or non-recycled materials. Even if recycled materials are used today, they are close to systems or policies rather than aesthetics. With this result, green aesthetics is a very difficult concept. Second, green products are usually 30% more expensive than general products. But every consumer has his or her own economical conditions, and nobody can coerce consumers into buying expensive green products for green environments. And green products without good quality cannot satisfy consumers. This means that green concept is not accomplished by just manufacturing green products. Third, although a lot of proposals have appeared as green design in exhibitions, most of them are close to craft because they are so hard to be manufactured. Manufacturing is the first consideration for products. These three issues are enough to explain why green concept is complicated in manufacturing products. If they are not solved, the green concept is just a fiction. So if this study proposes a turning point against blind green-oriented atmosphere, it will be meaningful enough.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.1
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• pp.1-10
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• 2018

During early pregnancy, before the development of a functioning thyroid gland, thyroid stimulating hormone (TSH) is a very sensitive marker of thyroid dysfunction during pregnancy. Normal values have been modified during gestation with a downward shift. The fetus is influenced by the TSH supplied by the mother. TSH and free thyroxine (FT4) concentrations vary during pregnancy and conventional units can vary between laboratories. A downward shift of the TSH reference range occurs during pregnancy, with a decrease in both the lower and upper limits of maternal TSH, relative to the typical non-pregnant TSH reference range. Each laboratory produces its own reference TSH and FT4 concentrations because there are many different assays that yield different results in pregnancy. Therefore, automated immunoassays used for serum FT4 analysis are still used widely, but the important considerations discussed above must be noted. The use of population-based, trimester-specific reference ranges remains the best way to handle this issue The slight downward shift in the upper reference range of TSH occurring in the latter first trimester (7~12 weeks) of pregnancy, typically not observed prior to 7 weeks. Their use indicates high or low levels in a quantitative manner independent of the reference ranges. These data highlight the importance of calculating population-based pregnancy-specific thyroid parameter reference intervals. A precision medicine initiative in this area will require the collection and analysis of a large number of genetic, biological, psychosocial, and environmental variables in large cohorts of individuals. Large prospective randomized controlled trials will be needed to resolve these controversies.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.5
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• pp.343-353
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• 2013

Recently, the landscape change by development has become more important and it's been stipulated that environmental effects evaluation must include LIA which reflects the said issue. Even though the selection of viewpoints which have the biggest impact on LIA result is stipulated in accordance with related rules, the criteria are inconsistent. Therefore, LIA experts' or project developers' subjective opinions have been very influential. In this case, wrong viewpoints which do not meet the selection criteria could be selected based on a discretionary interpretation on them, which could in turn substantially reduce an accuracy and reliability of the LIA results. Therefore, this research suggested the reverse-viewshed frequency technique as method that can be verified accuracy and reliability of viewpoints. And it has comparatively analyzed effective viewpoints using reverse-viewshed frequency analysis on viewpoints which were selected for LIA. As a result, the average validity was just 58% of total viewpoints used in construction sites. And the validity of viewpoints decreased as viewshed frequency increased. Based on results above, it was able to verify that the unreasonable points of a substantial proportion have been used as viewpoints in LIA process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.619-626
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• 2020

The development of new antifreeze mixtures containing non-amine-type corrosion inhibitors, which considers environmental protection, has become a major issue. In this study, four non-amine-type corrosion inhibitors were synthesized and used to produce five kinds of new antifreeze for automobiles to evaluate the rate of copper corrosion. The effects were evaluated by the weight change, surface observation, roughness measurement, and measurement of copper elution in the solution. The amount of copper eluted measured by ICP from Sample 4 was small, and the elution rate was prolonged. Sample 4 showed the best anti-corrosion performance owing to a corrosion suppression effect by passivating copper because the metal surface was smooth after the test, and the corrosion product layer was formed evenly on the surface as small local corrosion was observed. The major corrosion inhibitor added to Sample 4 was 1-aminomethyl(N',N'-di(2-hydroxyethyl)benzotrazole, which contained a certain amount in Sample 5 to show relatively high local corrosion but passivation in progress. Therefore, among the four corrosion inhibitors, 1-aminomethyl(N',N'-di(2-hydroxyethyl)benzotrazole had the highest corrosion inhibitory effect. This corrosion inhibitor prevents corrosion by promoting the passivation of copper on the antifreeze.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.1
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• pp.125-132
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• 2017

Objective: Along with increasing livestock products via intensive rearing, the accumulation of livestock manure has become a serious issue due to the fact that there is finite land for livestock manure recycling via composting. The nutrients from livestock manure accumulate on agricultural land and the excess disembogues into streams causing eutrophication. In order to systematically manage nutrient loading on agricultural land, quantifying the amount of nutrients according to their respective sources is very important. However, there is a lack of research concerning nutrient loss from livestock manure during composting or storage on farms. Therefore, in the present study we quantified the nutrients from dairy cattle manure that were imparted onto agricultural land. Methods: Through investigation of 41 dairy farms, weight reduction and volatile solids (VS), total nitrogen (TN), and total phosphorus (TP) changes of dairy cattle manure during the storage and composting periods were analyzed. In order to support the direct investigation and survey on site, the three cases of weight reduction during the storing and composting periods were developed according to i) experiment, ii) reference, and iii) theoretical changes in phosphorus content (${\Delta}P=0$). Results: The data revealed the nutrient loading coefficients (NLCs) of VS, TN, and TP on agricultural land were 1.48, 0.60, and 0.66, respectively. These values indicated that the loss of nitrogen and phosphorus was 40% and 34%, respectively, and that there was an increase of VS since bedding materials were mixed with excretion in the barn. Conclusion: As result of nutrient-footprint analyses, the amounts of TN and TP particularly entered on arable land have been overestimated if applying the nutrient amount in fresh manure. The NLCs obtained in this study may assist in the development of a database to assess the accurate level of manure nutrient loading on soil and facilitate systematic nutrient management.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.350-359
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• 2009

This thesis in the social welfare-related institutions in the Seoul area, art therapy and the therapist based on the status of welfare-related agencies in the community of art therapy is to present possibilities and challenges. Research results presented by Health and Welfare, where seven of the 14 kinds of social welfare facilities, participate in the survey and the target organ, 45.1% of art therapy's role in social welfare-related institutions and gradually establish the location was the result. Art therapy is to conduct the current difficulties in institutions about the environmental factors related to a professional therapist and art therapist in the therapist's expansion as a major research and maintenance was network. Welfare-related agencies and community relationships we maintain mutual relationship, and are formed within the community have an effect on consciousness and collectivization. To provide the opportunity which realize the value in the art therapy by applying more to expand the variety of professional method. First, secure the facility of art therapy environment and the therapists. Second, if the art therapy association secures the integrated system, it makes a connection with professional therapists to improve recruitment environment in the art therapy community and therapists need to be addressed by all involved is a challenge. Third, a therapist for the duration of training in order to access a variety of academic and clinical research is the importance of the process of learning the training and supervision is to discuss the issue.