• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.537-541
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• 1999

Fish heads of the main by-product is fishery processing were treated to extract nutrients by heating the fish heads with 1.5 or 3.0 times added water during 9, 12 or 15 hours. The yield, chemical compositions and physical properties of the hydrothermal extracts were studied. The yield was increased with the amount of water added and the extracting hours. The extract contained about $80\%$ protein in solid basis, but has no lipid. In essential amino acid, glutamic acid was most abundant and Iysine was abundant. In free amino acid, $\delta$-hydroxylysine and L-histidine in Cypyrinus carpio linnaeus had 5 times more than those in Onchorhynchus keta, The solution of the extracts was known as Newtonian fluid and the color of the extracts showed lower whiteness, higher redness and higher yellowness.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.3
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• pp.76-88
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• 2016

Machine to Machine (M2M) is a technology that presents communication between two or more devices with or without human intervention. M2M communications can be applied for various use cases such as environmental monitoring, health care, smart metering and etc. In most use cases, M2M utilizes sensor nodes to collect data from the intended environment and the data is transmitted back to M2M application through other devices (gateways, sink nodes). In some use cases, M2M devices are being designed to store and process sensor data for improving the reliability of the service; Gateways and sink nodes are also intended to store and process the gathered data from sensor nodes. This kind of approach is very challenging for both academy and industry. In order to enhance the performance of this approach, in this paper, we propose our Common Service Security Platform (CSSP) for M2M devices and gateways. CSSP platform presents solutions for the devices and gateways by making them operate more accurately and efficiently. Besides, we present a comparative analysis of communication protocols and present their performance in accordance with selected metrics.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.467-467
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• 2016

암거는 일반적으로 용수나 배수용의 수로가 도로, 철도, 제방 등의 아래에 매설 된 수로를 지칭한다. 이러한 암거는 산업발전으로 사회기반시설의 신설 및 확충, 재정비 등으로 많이 활용되고 있다. 최근 들어 기후로 인한 재해가 급증하면서 이러한 시설물에 대한 안정성 및 관리에 대한 관심이 높아지고 있는 것이 현실이다. 특히 소하천은 집수면적 및 유로연장이 짧고 하상경사가 급하기 때문에 홍수에 취약하다. 즉, 빨라진 유속으로 인해 구조물 주변의 세굴에 의한 유실, 토사유출로 인한 하상퇴적, 부유물로 인한 차단으로 인해 통수에 지장을 받아 피해가 발생하게 된다. 이러한 암거시설물 피해는 2차 피해로 이어질 수 있으며 사회기반시설 파괴로 도시기능이 마비되고 인근 주변지역에 침수로 인한 재산 및 인명피해까지 발생시킬 수 있는 피해 잠재능력을 보유하고 있다. 그러나 피해에 대한 예방대책은 유지관리를 통해 지속적으로 관리하는 것이 대부분의 지침 등에 소개된 내용들이다. 본 연구에서는 암거를 대상으로 암거의 폐색으로 인해 암거주변에서 변화되는 흐름특성을 축소모형을 통해 검토하고자 하였다. 암거 축소모형실험은 1.5m 폭을 갖는 직선수로에서 수행하였으며, 암거모형은 도로암거표준도(2008)를 참조하여 $3m{\times}3m$ 수로암거를 대상으로 1/10 축소모형을 제작하였다. 암거유입부 퇴적으로 인한 암거의 차단률(차단면적/암거단면적)은 차단이 발생하지 않는 0% 조건에서부터 10%, 20%, 30%, 40%, 50% 조건에 대해 실험을 수행하였다. 실험결과 차단에 따른 암거 상류단의 수위는 차단이 없는 암거의 경우에 비해 차단율이 높아질수록 암거유입부 수위는 20.4% ~ 82.7% 상승하는 것으로 나타났다. 암거의 차단률이 40% 이상일 경우 높아진 수위로 인해 암거통로의 윗상면부까지 다다르고 있으며 50%일 경우 암거를 통과하는 흐름이 자유수면흐름이 아닌 오리피스 흐름이 발생하는 것으로 나타났다. 암거유입부 차단으로 인한 암거주변의 최대유속은 암거 직하류부에서 주로 발생하여 암거 유출부에서의 최대유속은 차단율이 증가할수록 선형적으로 증가하는 것으로 나타났으며 암거 유출부에서의 유속은 차단전의 조건(0%) 대비 4.2% ~ 35.5% 까지 상승하는 것으로 나타났다. 이와 같은 결과를 토대로 고려하였을 때 대부분 산지부에서 설치되는 암거의 경우 유속이 불가피하게 증가하게 됨으로 유속에 따른 유속조절방안(차단 및 우회시설) 및 세굴대책을 세워야 할 것으로 판단된다.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.903-915
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• 2011

Recently, anaerobic methane production of agricultural waste biomass has received increasing attention. Until now domestic BMP (Biochemical methane potential) studies concerned with agricultural waste biomass have concentrated on the several waste biomass such as livestock manure, food waste, and sewage sludge from WWTP (Waste water treatment plant). Especially, the lack of standardization study of BMP assay method has caused the confused comprehension and interpretation in the comparison of BMP results from various researchers. Germany and USA had established the standard methods, VDI 4630 and ASTM E2170-01, for the analysis of BMP and anaerobic organic degradation, respectively. In this review, BMP was defined in the aspect of organic material represented as COD (Chemical oxygen demand) and VS (Volatile solid), and the influence of several parameters on the methane potential of the feedstock was presented. In the investigation of domestic BMP case studies, BMP results of 18 biomass species generating from agriculture and agro-industry were presented. And BMP results of crop species reported from foreign case studies were presented according to the classification system of crops such as food crop, vegetables, oil seed and specialty crop, orchards, and fodder and energy crop. This review emphasizes the urgent need for characterizing the innumerable kind of biomass by their capability on methane production.

• Journal of the Korean Geotechnical Society
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• v.37 no.10
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• pp.13-25
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• 2021

The most widely used method for determining the blast effects of explosives is the Trauzl test. This test is used to measure the explosive power (strength) of a substance by determining volume increase, which is produced by the detonation of a tested explosive charge in the cavity of a lead block with defined quality and size. In this paper, Trauzl lead block test and High speed 3D-DIC (Digital Image Correlation) system were conducted to evaluate the stemming effect of the blast hole. The effects of stemming materials can be expressed as the expansion of the cavity in a standard lead block through explosion of the explosives. The blasting experiment was conducted with emulsion explosives. The stemming material in the blast hole of lead block, which was adopted in this study, were using sand and stone chips. Results of blasting experiment and numerical analysis showed that the expansion rates of lead block were most affected by stone chips followed by sand. Also, as result of dynamic strain measurement on the lead block surface of High speed 3D-DIC system, the displacement and surface strain on the block were the highest in the experiment case of stone chips stemming.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.550-560
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• 2018

Many countries have provided support for research and development and implemented policies for Advanced Driver Assistance Systems (ADAS) for enhancing the safety of vehicles. With such efforts, the toll of casualties due to traffic accidents has decreased gradually. Korea has exhibited the lowest toll of casualties due to traffic accidents and is ranked 32nd in mortality among the 35 OECD members. Traffic accidents typically fall into three categories depending on the cause of the accident: vehicle to vehicle (V2V), vehicle to pedestrian (V2P), and vehicle independent. Most accidents are caused by drivers' mistakes in recognition, judgment, or operation. ADAS has been proposed to prevent and reduce accidents from such human errors. Moreover, the global automobile industry has recently been developing various safety measures, but on-road tests are still limited and contain various risks. Therefore, this study investigated the international standards for evaluation tests with regard to the assessment techniques in braking capability to cope with the limitations of on-road tests. A theoretical formula for braking force and a control algorithm are proposed, which were validated by comparing the results with those from an on-road test. These results verified the braking force depending on the functions of ADAS. The risks of on-road tests can be reduced because the proposed theoretical formula allows a prediction of the tendencies.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.175-180
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• 2018

In this study, CFRP was manufactured with the laminate angle of $45^{\circ}$. The specimen of TDCB bonded with the adhesive for structure was designed by CATIA and the analysis was progressed by using the finite element analysis program of ANSYS. This study model was designed on the basis of British industry and ISO standard and the configuration factor(m) was established with variable according to the angle of model configuration. As the study result of this paper, the maximum deformations at the specimens with the tapered angles of $4^{\circ}$ and $8^{\circ}$ become most as 12.628 mm and least as 12.352mm respectively. Also, the maximum equivalent stresses at the specimens with the tapered angles of $6^{\circ}$ and $8^{\circ}$ become most as 9210.3 MPa and least as 4800.5 MPa respectively. The damage data of TDCB structure with the laminate angle which was manufactured with CFRP could be secured through this study result. As the damage data of TDCB structure bonded with CFRP obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the machine or structure at real life.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.565-572
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• 2019

As a public research institute, government-supported institutes have led the industrial development and the advancement of science and technology in Korea. Robert Levering has annually selected 'Fortune 100 GPTW(Great Place to Work)' by measuring the Trust Index which was originated by himself. The objectives of this study are to attempt newly to analyze the inter-relations among 5 elements of GPTW trust index such as credibility, respect, fairness, camaraderie, and pride perceived by the K institute's 262 employees; to verify that GPTW trust index is valid for the selection of the fortune 100 GPTW. Amart PLS 2.0 and SPSS 18 were utilized for the statistical analysis. The results of this study are as follows. Credibility has positive effect to pride; respect has positive effect to pride and camaraderie; fairness has positive effect to camaraderie; and camaraderie has positive to pride. Pride and camaraderie have positive effect to the perceived GPTW. Recent studies mainly focused on the relations between GPTW trust index as independent, mediating variables or parameters and organizational performances. It is meaningful that this study has firstly tried to analyze the inter-relations among 5 elements of the trust index for the employees of research institute. This study has implication that the in order to enhance the performance the institute has to manage GPTW trust index perceived by the employees.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.781-792
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• 2018

In modern society, as technology develops and industry diversifies, students can choose from a variety of career paths. Since science, technology, engineering, and mathematics require a longer education and experience than other fields, it is important to design science education policies based on the competencies required for science, technology, engineering, and mathematics (STEM) occupations. This study explores the definition of science and technology manpower and STEM occupations and identifies core competencies of STEM occupations using standard job information operated and maintained by the US Department of Labor ($O^*NET$). We specially analyzed ratings of the importance of skills (35 ratings), knowledge (33 ratings), and work activities (41 ratings) conducting descriptive analysis and principal component analysis (PCA). As a result, core competencies of STEM occupations consist of STEM problem-solving competency, Management competency, Technical competency, Social service competency, Teaching competency, Design competency, Bio-chemistry competency, and Public service competency, which accounts for 70% of the total variance. This study can be a reference for setting the curriculum and educational goals in secondary and college education by showing the diversity of science and technology occupations and the competencies required for STEM occupations.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1327-1337
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• 2018

Aviation fuel oil is more strictly controlled than other transport fuels because it can lead to major accidents in the event of a problem. The quality standards of the aircraft are specified by the domestic Korean Standard, the American Society for Testing and Materials and the International Air Transport Association, respectively. From 2016 to 2017, the quality analysis of 6 items such as aromatic content, sulfur content and distillation characteristics was carried out on the jet fuel produced at five domestic refineries. Domestic production of jet fuel has been shown to be in conformity with the quality standards and has been maintained at a constant level throughout the year. Compared with the specification of ASTM and IATA the aromatic content of domestic KS specification is set to be strictly 1.5 wt% higher than the ASTM and IATA setting specification, but it satisfies this specification sufficiently. In addition, other items such as sulfur content, distillation property and flash point satisfied both domestic and international specification.