• 전기의세계
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• 제30권1호
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• pp.47-54
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• 1981

The fabrication of Langevin type vibrators producing relatively high sonic and ultrasonic energy is described. The dependence of the acoustic output and the frequency characteristics on the thickness of the steel plates and the pressure at the ceramics are investigated. As results, the acoustic output of Langevin type vibrators are relatively high, and the resonant frequency is decreassed by thickening the steel plates and lowering the pressure at the ceramics. Using these results, sonic and ultrasonic vibrator whose resonant frequency is determined can be designed.

• 대한가정학회지
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• 제36권2호
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• pp.1-18
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• 1998

The purpose of this study is to investigate some influencing factors related to housewives' environmental concern and environmental management behavior. Data were collected from questionaire with 786 housewives who live in Jeonbuk area. The results could be summarized as follows. The level of environmental concern was relatively high and differed significantly according to the level of innovation, residence, the level of education, and age of wives. But the level of environmental management behavior was relatively low, especially clothing disposal behavior and buying something to eat. These findings pointed that the program of environmental education should be more pragmatic.

• 한국세라믹학회지
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• 제17권1호
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• pp.35-41
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• 1980

Alumina extraction from raw Hadong kaolin with sulfuric acid was studied to obtain relatively pure alumina. Factors as acid concentration, heating temperature and conditions of ammonium alum crystal formation from extracted solution are also surveyed and most of iron oxide in kaolin is eliminated in crystallization of ammonium alum. Pure crystal obtained from the extracted solution with ammonium sulfate is relatively free from iron containment in mother liquor. Alumina in ammonium alum crystal is converted to gibbsite form after complete hydrolysis in ammonia gas.

• Journal of Chest Surgery
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• 제22권3호
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• pp.498-502
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• 1989

Carcinosarcoma is the group of neoplasms possessing both carcinomatous parenchyma and sarcomatous stroma. These tumors are relatively uncommon and may arise in variable organs. In this case, a 62-year-old male patient was admitted to our department due to left chest pain and general weakness of three months duration. The chest x-ray revealed egg-sized, relatively well defined lobulated soft tissue mass in left paracardiac area. Left lower lobectomy was performed under the preoperative impression of lung cancer. Pathologic examination of the resected lung revealed carcinosarcoma without regional lymph node metastasis. Patient is doing well at present without any chemotherapy.

• Bulletin of the Korean Chemical Society
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• 제19권11호
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• pp.1198-1202
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• 1998

Aminolysis of aryl thiol-2-furoates and thiol-2-thiophenates with benzylainines are investigated in acetonitrile at 50.0 ℃. Relatively large selectivity parameters, ρx(βx), ρz(βx) and ρxz (> 0) together with the valid reactivity-selectivity principle are consistent with a stepwise acyl transfer mechanism with rate-limiting expulsion of the leaving group, thiophenolate anion, from the tetrahedral intermediate, T±. The first-order kinetics with respect to the benzylamine concentration and the relatively large secondary kinetic isotope effect involving deuterated benzylamine nucleophiles suggest a four-center type transition state in which concurrent leaving group departure and proton transfer are involved.

• 대한수학회보
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• 제26권2호
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• pp.115-118
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• 1989

• 대한수학회보
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• 제24권1호
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• pp.53-54
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• 1987

• 한국언론정보학보
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• 제78권
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• pp.141-176
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• 2016

본고는 기존의 미디어산업 분석에서 사용된 정태적 집중지표가 일부 유형에 한정되어 있다는 것에 주목하고 새로운 정태적 집중지표의 활용 가능성을 탐색하였다. 특히, 산업 내의 불평등 구조를 포착하는 타일지수는 미디어 산업의 정태적 분석에 있어서 유용하게 사용될 수 있다. 동태적 경쟁을 포착하는 여러 유형의 이동지표도 미디어 산업을 동태적 시각에서 분석하는 데에 있어서 다양한 정보를 제공한다. 타일지수와 이동지표들을 활용하여 2001년에서 2015년까지 전국종합일간지 시장구조를 분석한 결과는 다음과 같다. 시장규모 변화 추세를 보면 매출액 규모는 감소했다. 반면에 자산 규모는 U자형의 추세를 보였는데, 이는 자기자본비율의 증가에 기인한다. 또한 발행부수 및 유료부수 규모도 감소했다(2010~2014년). 자산 기준으로 보면 시장집중도 뿐만 아니라 조중동 그룹과 기타 그룹 간 불균등도가 이명박 정부에서 가장 높았다. 매출액 기준으로 보면 시장집중도는 노무현 정부에서 가장 낮았으며 그룹 간 불균등도는 박근혜 정부 초기에서 가장 높았다. 전반적으로 신문사들의 자산과 매출액은 각각 평균으로 수렴하려는 이동성을 보였다. 그리고 자산에 비해 매출액으로, 매출액에 비해 발행부수로 시장점유율을 측정할 경우에 동태적 경쟁의 정도는 약하게 나타났다.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.440-449
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• 1994

Current risk assessment practices largely reflect the need for a consistent set of relatively rapid, first-cut procedures to assess 'plausible upper limits' of various risks. These practices have important roles to play in 1) screening candidate hazards for initial attention and 2) directing attention to cases where moderate-cost measures to control exposures are likely to be warranted, in the absence of further extensive (and expensive) data gathering and analysis. A problem with the current practices, however, is that they have led assessors to do a generally poor job of analyzing and expressing uncertainties, fostering 'One-Number Disease' (in which everything from one's social policy position on risk acceptance to one's technical judgment on the likelihood of different cancer dose-response relationships is rolled into a single quantity). At least for analyses that involve relatively important decisions for society (both relatively large potential health risks and relatively large potential economic costs or other disruptions), we can and should at least go one further step - and that is to assess and convey both a central tendency estimate of exposure and risk as well as our more conventional 'conservative' upper-confidence-limit values. To accomplish this, more sophisticated efforts are needed to appropriately represent the likely effects of various sources of uncertainty along the casual chain from the release of toxicants to the production of adverse effects. When the effects of individual sources of uncertainty are assessed (and any important interactions included), Monte Carlo simulation procedures can be used to produce an overall analysis of uncertainties and to highlight areas where uncertainties might be appreciably reduced by further study. Beyond the information yielded by such analyses for decision-making in a few important cases, the value of doing several exemplary risk assessments in. this way is that a set of benchmarks can be defined that will help calibrate the assumptions used in the larger number of risk assessments that must be done by 'default' procedures.

• 한국실내디자인학회논문집
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• 제19권4호
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• pp.82-89
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• 2010

The studies published up to now, related to the correlation between spatial structure and visitors' behavior in a museum are rather relatively lacking when it comes to the in-depth consideration for the effect of the actual exhibition environment. So the main purpose of this study is to define the correlation between the light environment and the visitors' behavior. Towards this end, this study uses 'space syntax' to quantify the spatial structure with 'integration', 'connectivity' and 'control value'. Meanwhile, 'tracking score' and 'tracking frequency' were selected as the scope among the indices of behavior's analysis. The results of this study are as follows; First, integration and correlation of tracking score and tracking frequency are lowest when it comes to the extra large historical museums where the difference of intensity of illumination by each convex space. Meanwhile, the most considerable effect is exerted by control value. Compared to tracking score, tracking frequency is closely related to 'syntactic variables'. Second, visitors do not take the short cut the dark exhibition space even when very dark exhibition spaces continue after passing through relatively bright space. Analysis of visitors' behavior by control value in the exhibition space composed of this type of intensity of illumination environment is not valid. Third, visitors move to relatively brighter transitional space compared to the exhibition space with low intensity of illumination when passing through dark exhibition continually. Meanwhile, when visitors pass through the exhibition space there is some difference intensity of illumination they move to relatively dark exhibition center among the subsequent exhibition spaces. Accordingly, when the composition of exhibition space that continues onto the environment of low intensity of illumination is inevitable, differentiating intensity of illumination appropriately would be effective in inducing visit to the subsequent exhibition space.