• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.5
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• pp.99-105
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• 2007

This paper describes the investigation on the spot in relation to electrical safety of electrical installation in elementary middle high school. The investigation was carried out for power receiving system, classroom, chemistry room, music hall and so on. The investigation on the spot was performed by researcher, the related expert, engineer with over fifteen years of industry experience all over the country. As a result of investigation on the spot to 41 schools, common grounding methods at power receiving system were dominant. The risk factors include absence of control box of electric fan, non-installation of earth leakage circuit breaker to power source of experiment stand, use of non-grounding outlet.

• Journal of Communications and Networks
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• v.13 no.5
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• pp.472-480
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• 2011

In this paper, we investigate two new candidate transmission schemes, non-orthogonal frequency reuse (NOFR) and beam-hopping (BH). They operate in different domains (frequency and time/space, respectively), and we want to know which domain shows overall best performance. We propose a novel formulation of the signal-to-interference plus noise ratio (SINR) which allows us to prove the frequency/time duality of these schemes. Further, we propose two novel capacity optimization approaches assuming per-beam SINR constraints in order to use the satellite resources (e.g., power and bandwidth) more efficiently. Moreover, we develop a general methodology to include technological constraints due to realistic implementations, and obtain the main factors that prevent the two technologies dual of each other in practice, and formulate the technological gap between them. The Shannon capacity (upper bound) and current state-of-the-art coding and modulations are analyzed in order to quantify the gap and to evaluate the performance of the two candidate schemes. Simulation results show significant improvements in terms of power gain, spectral efficiency and traffic matching ratio when comparing with conventional systems, which are designed based on uniform bandwidth and power allocation. The results also show that BH system turns out to show a less complex design and performs better than NOFR system specially for non-real time services.

• Knowledge Management Research
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• v.21 no.2
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• pp.119-135
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• 2020

Owing to pandemic (COVID-19), the traditional face-to-face education method has been changed to the non-face-to-face real-time online education methods. Using a real time-based video conference system, synchronous education can be adopted by face-to-face class easily. Specially, it is very important to minimize the difference in learning effects between face-to-face and non-face-to-face in Entrepreneurship education. In this study, in order to derive the factors that affect the satisfaction of learners in synchronous online education, authors collected data from learners taking a synchronous entrepreneurship course. Through previous research, learned the reality of education and the composition of lessons. Spatiotemporal effectiveness, mentor ability, and educational environment influence learning satisfaction. PLS-SEM results revealed that it was confirmed that only spatiotemporal effects affect learner satisfaction. However, the education environment (fluent operation and convenience of function use of real-time based online conference system) effect teaching presence, class structure, and spatiotemporal effects. Through this research, we hope to provide theoretical and practical support for developing effective teacher activities, proper lesson structure, convenient function of the conference system, and learner-centered online learning environment when developing synchronous online classes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4241-4244
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• 2012

The lung adenocarcinoma is considered more aggressive than other types of non-small cell lung cancer. As metabolites of tryptophan degradation along the kynurenine pathway, including kynurenic acid, have been shown to induce immunosuppression and facilitate escape of tumor cells from immune surveillance, a hypothesis was set up that differences in biological behavior between types of lung cancer may be associated with altered activity of the kynurenine metabolic pathway. The aim of the study was to determine kynurenic acid levels in the serum of patients with bronchial adenocarcinoma for comparison with other types of non-small cell lung cancer. A total of 227 patients with non-small cell lung cancer were enrolled in the study, including 71 with adenocarcinoma and 96 with squamous cell carcinoma. Serum kynurenic acid concentration was determined with use of high performance liquid chromatography and fluorometry. The level of kynurenic acid in the serum of patients with adenocarcinoma was significantly higher than in those with squamous cell lung cancer ($107.1{\pm}62.8$ pmol/ml; 95%CI: 92.4 to 132.3 pmol/ml versus $82.1{\pm}47.6$ pmol/ml; 95%CI: 78.5 to 91.2 pmol/ml, respectively; p = 0.027). Differences between other histological types of lung cancer were insignificant. We conclude that increased activity of kynurenine metabolic pathway manifested by elevated serum kynurenic acid level may be one of the factors associated with clinically distinct biological behavior of adenocarcinoma, in particular high invasiveness and rapid progression.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.90-103
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• 2022

The purpose of this study is first to understand whether technology innovation capability, which is considered an important factor in the Root companies, directly affects the business performance of the company. Second, it was attempted to determine whether internal resources deemed necessary for a company's continuous competitive advantage and excellent business performance play a mediating role in the technological innovation capability of the Root companies and the business performance. The implications of this study derived from the research results are as follows: Among the elements of technology innovation capability, R&D capability, positively affects both financial and non-financial performance. It was confirmed that the investment ratio could positively affect financial performance such as sales, market share, and yield, and non-financial performance such as corporate image, employee satisfaction, and productivity. Among the factors of technology innovation capability, the technology innovation system positively affects both financial and non-financial performance. Therefore, it can be said that securing rights to owned technology, establishing technology and funding, efficient use of resources, etc., affects financial performance such as sales or market share of a company, and affect the company's production capacity, image, and employee satisfaction. It has been verified that internal resources, including financial, physical, and human resources, can mediate between the three elements of technology innovation capability and corporate financial and non-financial performance.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.221-221
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• 2015

Sustainable use of water resource and conservation of water quality are essential problems in the world. Especially, problems of water quality are serious one for human health as well as ecological system of all creatures on the earth. Recently, the importance of total effluent load as well as the concentrations of pollutant materials has been recognized not only for the conservation of water quality but also for sustainable water use in watersheds. However, the measurement or estimation of total effluent load from non-point source area such as farm lands or forests may be more difficult because both of concentration and discharge of the water are greatly changed depending on various factors especially metrological conditions such as rainfall, while the measurement from a point source area may be easy because the concentration of pollutant materials and amount of discharge water are relatively steady. Therefore, the total effluent load from a non-point source is often estimated by statistical relationships between concentration and discharge, which is called as L-Q equation. However, a lot of work and time are required to collect and analyze water samples and to get the accurate relationship or regressive equation. So, we proposed a new system for direct measurement of total effluent load of water quality from non-point source areas to solve the problem. In this system, the overflow depth at a hydraulic weir is measured with a pressure gage every hourly interval to calculate the amount of hourly discharge at first. Then, the operating time of a small electric pump to collect an amount of water which is proportional to the discharge is calculated to intake the water into a storage tank. The stored water is taken out a few days later in a case of storm event or several weeks later in a case of non-rainfall event and the concentrations of water quality such as total nitrogen and phosphorous are analyzed in a laboratory. Finally, total load of the water quality can be calculated by multiplying the concentration by the total volume of discharge. The system was installed in a small experimental forestry watershed to check the performance and know the total load of water quality from the forest. It was found that the system to collect a proportional amount of water to actual discharge operated perfectly and a total load of water quality was analyzed accurately. As the result, it was expected that the system will be very available to know the total load from a non-point source area.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.3069-3085
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• 2018

In this study, we examined the effect of non-cognitive factors on job tenure and tenure using KLIPS. We examine the internal consistency of the big5 personality trait and of the locus of control, and use the parameterized proportional hazards model. As a result, we confirmed that non-cognitive skill such as personality traits and locus of control affect individual labor market performance. Conscientiousness has shown that the job seeking period of adult job seekers is lengthened, thereby lowering the unemployment rate. It can be understood that high attentiveness under uncertainty can misinterpret information, and that lack of decision restricts escape from unemployment. In the tenure analysis, people with internal locus of control tendency were less likely to leave the job due to longer tenure. Those who have internal control can not only be preferred by the organization but also the internal control tendency seems to be the factor that maintains the long-term job because of the motivation and self-control of their actions.

• Journal of computational fluids engineering
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• v.22 no.1
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• pp.88-94
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• 2017

The IR signal entering into a sensor is composed of the following components: the self-emitted component directly from the object surface, the reflected components of the solar and sky irradiance at the object surface, and the scattered component by the atmosphere without reference to any object surfaces. The self-emitted and reflected components from the object can be lowered by the atmospheric layer between the object and the IR sensor. The principle factors influencing the atmospheric transmittance are the air temperature, the relative humidity and the observation distance. Previous studies on IR signal transmission through the atmosphere are focused on uniform atmospheric conditions and the non-uniform nature of the atmosphere was not properly treated in modeling. In this study, we use the local atmospheric transmittance to simulate the non-uniform atmosphere in analyzing the IR signal from the object surface. The results show that the nonuniform analysis of the atmosphere becomes more important as the wavelength of IR signal increases.

• Korean Journal of Environment and Ecology
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• v.3 no.1
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• pp.81-94
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• 1989

Use impacts to trail and campground deteriorations and their changes of natural environment were studied in Mt. Kaya National Park in 1989. The entire width, bare width and maximum depth of trail as the trail condition were significantly greater on the more heavily used trail. Deteriorations of trail which were surveyed at the total of 51 were significantly different from those of non-deteriorated points. The changes of soil and vegetation of trailsides were not found at a uniform tendency but could be more clearly grouped by the types of user's disturbance, and use impact on trailside had reached 15m inside of forest. Percentage of area for Class 5 in campsite was about 36% and about 69% of campsite area was more severe than Class 3. Recreational activities retarded the diameter growth of trees in campsite and accelerated the different composition of species. Soil and vegetative factors adapted to understand the difference of use amount and the realm of use impact could be sorted. The realm influenced by user's disturbance was about 50m from the core of campsite. Fraxinus rhynchophylla, Rhus trichocarpa, Symplocos chinensis for. pilosa and Stephanandra incisa were considered as the tolerant species to user's impact.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.305-327
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• 1999

In the paper insight is given in the legislation policy to restrain environmental pollution by pig husbandry, focused on The Netherlands (Mineral Accounting System). Besides, nutritional measures are presented to reduce environmental pollution by lowering excretion of N and P, emphasizing (multi) phase feeding, the use of low protein, synthetic amino acids supplemented diets, phytase and its effect on phosphorus and calcium digestibility, its interaction with phytic acid and proteins, and the environmental impact of the use of phytase in pig diets. Also, nutritional means are indicated to reduce ammonia volatilization from pig operations. It is concluded that nutrition management can substantially contribute to reduction of N and P excretion by pigs, mainly by lowering dietary protein levels, (multi) phase feeding and the use of microbial phytase, and that the use of phytase on a large scale in The Netherlands has a tremendous environmental impact. In 20 years the excretion of P in growing-finishing pigs has more than halved. Ammonia emission from manure of pigs can be reduced substantially by lowering dietary protein content, but also by including additional non-starch polysaccharides in the diet. A very promising method to reduce ammonia emission is to manipulate dietary cation-anion difference, e.g. by adding acidifying salts to the diet, which will lower pH of urine substantially. Further research is desirable. This also applies to determining dietary factors influencing the odour release from manure. Finally, some speculation on the future of pig farming from an environmental viewpoint is presented.