• 한국산림과학회지
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• 제82권2호
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• pp.128-138
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• 1993

본 연구는 한국(韓國)의 임업실정(林業實情)에 부합되는 산림소득세(山林所得稅)의 개선방안(改善方案)을 다루고 있다. 특히, 그러한 개선방안(改善方案)이 결과적으로 임업투자(林業投資)를 촉진시킬 수 있도록 하기 위한 특별한 고려가 이루어졌다. 현행 산림소득세제(山林所得稅制)와 같이 인공조임목(人工造林木)에 대한 완전면제(完全免除)보다는 임업투자(林業投資)가 이루어지는 즉시 손금(損金)으로 처리할 수 있는 제도의 확립이 매우 중요하다는 것을 연구결과(硏究結果)를 통하여 밝혔으며, 이에 대한 구체적인 적용방법(適用方法)등에 관하여도 다각적인 검토가 이루어졌다. 또한, 이러한 제도는 이미 선진국(先進國)의 경우에 있어서도 보편적으로 채택되고 있음을 제시하고 있다.

• Journal of Welding and Joining
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• 제17권6호
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• pp.84-89
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• 1999

Most of ferrous b.c.c weld materials may experience martensitic transformation during rapid cooling after welding. It is well known that volume expansion due to the phase transformation could influence on the relaxation of welding residual stress. To apply this effect practically, it is a prerequisite to establish a numerical model which is able to estimate the effect of phase transformation on residual stress relaxation quantitatively. For this purpose, the analysis is carried out in two regions. i.e., heating and cooling, because the variation of material properties following a phase transformation in cooling is different in comparison with the case in heating, even at the same temperature. The variation of material properties following phase transformation is considered by the adjustment of specific heat and thermal expansion coefficient, and the distribution of residual stress in analysis is compared with that of experiment by previous study. consequently, in this study, simplified numerical procedures considering phase transformation, which based on a commercial finite element package was established through comparing with the experimental data of residual stress distribution by other researcher. To consider the phase transformation effect on residual stress relaxation, the transition of mechanical and thermal property such as thermal expansion coefficient and specific heat capacity was found by try and error method in this analysis.

• 전기학회논문지
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• 제61권9호
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• pp.1232-1241
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• 2012

The ac side current of an high voltage direct current (HVDC) converter is characterized by highly non-sinusoidal waveform. If the harmonic current is allowed to flow in the connected ac system, it may cause unacceptable levels of distortion. Therefore, ac side filters are required as part of the total HVDC converter station, in order to reduce the harmonic distortion of the ac side current and voltage to acceptably low levels. The ac side filters are also employed to compensate network requested reactive power because HVDC converters also consume substantial reactive power. Among different types of filters, double-tuned filters have been widely utilized for HVDC system. This paper presents two design methods of double-tuned filter; equivalent method and parametric method. Using a parametric method, in particular the paper proposes a new design algorithm for a realistic system. Finally, the performance of the design algorithm is evaluated for a 80kV HVDC system in Jeju island with PSCAD/EMTDC program. The results cleary demonstrate the effectiveness of proposed design method in harmonics elimination and steady-state stability.

• 한국전자통신학회논문지
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• 제13권6호
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• pp.1257-1262
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• 2018

본 논문에서는 보안 감시 카메라 영상을 활용하여 화재 검출을 위한 효과적인 심층학습 방안을 제안한다. AlexNet 모델을 기준으로 효과적인 화재 검출을 위한 커널 크기와 커널 이동 간격의 변화에 따른 분류 성능을 비교 분석한다. 학습을 위한 데이터셋은 정상과 화재 2가지 클래스로 분류한다, 정상 영상에는 구름과 안개 낀 영상을 포함하고, 화재 영상에는 연기와 화염을 각각 포함한다. AlexNet 모델의 첫 번째 계층의 커널 크기와 이동 간격에 따른 분류 성능 분석 결과 커널의 크기는 크고, 이동 간격은 작을수록 화재 분류 성능이 우수한 것을 확인할 수 있다.

• 전력전자학회논문지
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• 제27권5호
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• pp.425-430
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• 2022

A pumped storage power station is an important means to solve the problem of peak load regulation and ensures the safety of power grid operation. The doubly fed variable-speed pumped storage (DFVSPS) system adopts a doubly fed induction machine (DFIM) to replace the synchronous machine used in traditional pumped storage. The stator of DFIM is connected to the power grid, and the three-phase excitation windings are symmetrically distributed on the rotor. Excitation current is supplied by the converter. The active and reactive power of the unit can be quickly adjusted by adjusting the amplitude, frequency, and phase of the rotor-side voltage or current through the converter. Compared with a conventional pumped storage hydropower station (C-PSH), DFVSPS power stations have various operating modes and frequent start-up and shutdown. This study introduces the structure and principle of the DFVSPS unit. Mathematical models of the unit, including a model of DFIM, a model of the pump-turbine, and a model of the converter and its control, are established. Fast power control strategies are proposed for the unit model. A 300 MW model of the DFVSPS unit is established in MATLAB/Simulink, and the response characteristics in generating mode are examined.

• 대한조선학회논문집
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• 제61권4호
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• pp.278-288
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• 2024

According to International Association of Classification Societies (IACS) Unified Requirement (UR) E26, ships contracted for construction after July 1, 2024 should be designed, constructed, commissioned and operated taking into account of cyber security. In particular, ship network monitoring tools should be installed in accordance with requirement 4.3.1 in IACS UR E26. In this paper, we propose a Security Information and Event Management (SIEM) security policy model for ships as an effective threat detection method by analyzing the cyber security regulations and ship network status in the maritime domain. For this purpose, we derived the items managed in the SIEM from the maritime cyber security regulations such as those of International Maritime Organization (IMO) and IACS, and defined 14 detection policies considering the status of the ship network. We also presents the detection policy for non-expert crews to understand it, and occurrence conditions depending on the ship's network environment to minimize indiscriminate alarms. We expect that the results of this study will help improve the efficiency of ship SIEM to be installed in the future.

• 대한조선학회논문집
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• 제49권1호
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• pp.87-92
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• 2012

Alignment of the main plates during the tack welding is essential to block assembly since most of the curved blocks and outfitting parts are assembled on the jigs and fixtures. Tact welding of main plates is the initial process of the curved hull block assembly. Due to the heavy weight of the main plates it is difficult to locate the plate on the accurate position of the jig and fixtures before welding. The conventional masonry process requires much time and manual work in order to achieve the accurate alignment. This labour-intensive process results in relatively high errors and correction works. Due to their larger dimensions and heavier weights, these hull blocks are not ergonomically desirable and, therefore, various mechanical devices such as hydraulic balancers or hydraulic jigs are used for the plate alignment. In this study, the position-sensing scheme implemented by sensors is presented in order to align the main plates on the accurate position during the hull block assembly. Integrating the Infrared photo sensors and micro processor unit, a small scaled prototype of the position-sensing module is developed to determine the alignment of main plates.

• 산학경영연구
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• 제20권1호
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• pp.123-143
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• 2007

이 연구는 조세특례제한법상 세액공제 및 세액감면 등의 직접감면과 준비금 손금산입 등의 간접감면의 세제혜택이 기업가치와 관련성이 있는지를 Ohlson(1995)모형을 토대로 1999년부터 2001년까지 3개년도 제조업을 대상으로 총 497개를 대상으로 실증분석하였다. 연구결과 주주지분 장부가치측면에서 직접 감면제도에 의한 기업합리화 적립금(누적액)과 당기전입 기업합리화적립금이 기업가치에 긍정적인 정(+)의 영향을 미치는 것으로 나타났다. 이는 세제지원의 성격과 사후관리제도의 정도 및 지속성의 차이로 인하여 기업가치 관련성에 있어서 서로 차이가 있을 수 있음을 보여주는 것이라 할 수 있다. 특히, 주주지분 장부가치측면과 회계이익측면에서 각각의 감면제도가 기업가치에 미치는 정도의 차이가 있는 것으로 나타났다. 이는 정책당국에서 간접감면제도의 조세정책적 실효성을 재검토 할 필요성의 여지를 가질 수 있음을 보여주고 있다.

• 한국한의학연구원논문집
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• 제5권1호
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• pp.101-110
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• 1999

In Sasang constitutional medicine, the classification of Sasang constitutional types (Tae-Yang, Tae-Eum, So-Yang, and So-Eum) is important for the treatment. There are some problems with the methods used for classifying Sasang constitutional types; old methods such as pulse-palpation are not considered objective and recent methods such as immunohematology are considered expensive, painful and time-consuming. To overcome these problems, a body measurement and finger prints analysis were performed. The purpose of this study was to determine whether the palm prints and the palm creases could be helpful in classifying Sasang constitutional types. Thus, we looked for characteristics of the palm prints and the palm creases according to Sasang constitutional types. Before analyzing the palm prints and palm creases, 760 Korean (465 males, 295 females) were surveyed using two kinds of questionnaires for classifying Sasang constitutional types. As there were no Tae-Yang individuals, we were only able to identify the characteristics of the palm prints and the palm creases for Tae-Eum (288 persons), So-Yang (193 persons), and So-Eum (279 persons) individuals. In this study, the terminal points of D, closed crease, and open crease seemed to be helpful in classifying Tae-Eum and So-Eum individuals. Terminal point 11 and closed crease were frequent in Tae-Eum individuals; whereas, terminal point 7 and open crease were frequent in So-Eum individuals. Therefore, the palm prints and the palm creases seem to contribute to the classification of Sasang constitutional types.

• Journal of Nutrition and Health
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• 제39권6호
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• pp.529-538
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• 2006

The prevalence of chronic diseases have been rising in the developing countries because of their increased animal foods consumption and Western lifestyle. Lately, vegetarian diet that exclude animal products get public attention. The purpose of this study was to evaluate the nutritional status and dietary quality of vegetarians, and their consumption of vitamin K and was also assessed. Vegetarians including strict vegan and lacto-ovo-vegetarian consumed their diet at least over 6 months. Carnivores were gender and age matched with vegetarians and they consumed over 50% of protein and fat from animal sources. Current nutrient intakes and dietary quality were assessed using 3-day food records and intake of vitamin K was calculated from the data base of 'Provisional Table on the vitamin K contents of foods, USA'. Blood sample were collected and biochemical parameters and plasma phylloquinone concentrations were analyzed. Anthropometric data from vegetarian and carnivore were not significantly different. The intake of calories, protein, vitamin $B_2$, Ca and Zn of the vegetarians were remarkably lower than RDA for each nutrient. Moreover, index of nutritional quality and nutrient adequacy ratio of vegetarians were lower than those of carnivore. Vegetarian consumed less fat and the ratio of n-6/n-3 fatty acid was lower in vegetarian. The intake of essential amino acids in vegetarian was significantly lower than that of carnivore. The vitamin K consumption and plasma phylloquinone concentration of vegetarian were significantly higher than those of carnivore (p<0.05). The dietary vitamin K consumption was positively correlated with plasma phylloquinone levels in vegetarian (p<0.01).