• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.225-226
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• 2007

• Journal of Biosystems Engineering
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• 제13권3호
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• pp.11-19
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• 1988

분무량(噴霧量) 및 유량계수(流量係數)에 관(關)한 많은 연구(硏究)가 실험결과자료(實驗結果資料)에 기초하여 수행(遂行)되어졌다. 그러나 공시체(供試體)의 노즐의 특성(特性)에 따라서 유선(流線)의 특성(特性)이 다르므로 많은 실험결과(實驗結果) 및 해석(解析)이 서로 상치되는 점이 많다. 본(本) 연구(硏究)에서는 이론분석결과(理論分析結果)가 실험결과(實驗結果)와 다소 다르더라도 노즐 설계(設計)의 실제응용면(實際應用面)에서 필요(必要)한 노즐구조(構造)의 기본기능(基本機能)을 이론적(理論的)으로 분석(分析), 이해(理解)시키고저 한다. 이론분석(理論分析)의 결과(結果)는 다음과 같다. 공동면적(空洞面積)은 분구경(噴口徑), 와실경(渦室徑), 중자도구경(中子導溝徑) 및 중자도구각(中子導溝角)에 관계되고 있으며, 특히 중자도구각(中子導溝角)이 공동현상(空洞現象)에 큰 영향을 미친다. $$r_r{^6}-3r_o{^2}r_r{^4}+[3r_o{^4}+\frac{r_c{^4}r_o{^2}}{(r_c-r_g)^2\;tan^2{\theta}}]r_r{^2}-r_o{^6}=0$$ 반경방향(半徑方向) 힘의 요소(要素)로 인(因)한 유량계수(流量係數)($C_t$)는 산출식(算出式)은 아래와 같다. $$C_t=[1-(\frac{r_r}{r_o})^2]^{3/2}$$ 분무각(噴霧角)(${\alpha}$)은 공동반경(空洞半徑) 및 분구반경(噴口半徑)에 의(依)하여 변화(變化)된다. $${\alpha}=2\;tan^{-1}\(\frac{r^r}{\sqrt{r_o{^2}-r_r{^2}}}\)$$분무각(噴霧角)은 특히 와실유선각(渦室流線角)의 영향을 많이 받음을 시사하고 있다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.587-590
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• 2000

The new core making method economized on core sand requested. The new method is heating core box until it reaches reasonable temperature and then spraying core sand with core binder into core box. Inner temperature distribution have to uniform in order to form core of uniform thickness. Therefore, in this study we treat of inner temperature distribution of core box in priority. First, determine proper torch number. Next, optimize the torch position to minimize the average of absolute deviation(AVEDEV) of inner temperature. The results are as followed : 1. The torch number that makes inner temperature distribution about $300^\circ{C}$ uniformly is 25. 2. When $S_H$ and $S_V$ is 0.7, the torch position is optimized and AVEDEV is 5.85.

• 음성과학
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• 제10권4호
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• pp.229-239
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• 2003

The purposes of this study are; to investigate the swallowing mechanism of stroke patients with different consistencies through the modified barium swallowing(MBS); and to establish preliminary data on the differences in swallowing durations. 4 different kinds of consistency-water, nectar, pudding, and crackers-were given to 6 stroke patients and their swallowing durations recorded through the fluoroscopy were measured in 1/100 second units. The results show that first swallowing time(FST), the oral preparatory duration(OPD), and the pharyngeal response duration(PRD) were delayed in swallowing thicker consistencies. However, water exhibited delayed oral and pharyngeal phase relative to its consistency and 50% of subjects showed oral loss of water. The relationship between consistencies and swallowing durations and the clinical issues on the stroke population were discussed.

• Journal of Acupuncture Research
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• 제19권1호
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• pp.46-53
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• 2002

Objective : The purpose of this study is to find out the effects of Jungja and Jungseon-Hyeol on the patients of neck pain. Methods : A retrospective study has been carried out for 30 cases of neck pain patients who visited Dongseo Oriental Medical Hospital from August 1, 2001 to september 30, 2001. We have treated them with acupuncture treatment of Jungja and Jungseon-Hyeol. Results : We have found out the excellent effects of Jungja and Jungseon-Hyeol on the patients of neck pain. Conclusion : The acupuncture treatment of Jungja and Jungseon-Hyeol is useful on the patients of neck pain.

• 한국안전학회지
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• 제11권3호
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• pp.25-32
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• 1996

This study is a survey on the effect of working security and worksite environment connected to the worst case of noise and dust which was generated in the manufacturing workshop of machinery and easting. The noise intensity of the manufacturing process tends to increase up to the limited strength of 90db (A) or the higher during the last 4~5 years in 1990~1994. This result requires a significant improvement of worksite environment of unit workshop. The concentration of dust in the gouging process tends to increase to a significantly high level compared with other worksite, which also requires a local ventilation method to reduce the dust diffusion. Organic solvents used most frequently in the manufacturing process machinery were the aromatic hydrocarbons, but were gradually diversed in recent years.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2004년도 추계학술발표논문집(상)
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• pp.955-958
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• 2004

웹접근성은 능력, 기술이나 상황에 관계없이 모든 인터넷 사용자에게 제공되는 정보와 서비스의 가용성을 의미한다. 시각 장애인, 난독중자, 청각장애인 등과 같은 사용자 그룹은 대부분의 웹사이트에서 접근장벽을 경험하고 있다. 한국의 공공기관 웹사이트에 대한 접근성 보고도 2003년 최초로 발표되었으나, 지방 자치단체에 관한 것은 발표된 바 없다. 본 연구에서는 충북지역의 웹 접근성을 평가하였다. 그 결과 거의 보든 대상 사이트가 접근성이 떨어지며, 접근성 교육이 웹 관리자나 프로그래머에게 시급히 필요한 것으로 보인다.

• 한국정밀공학회지
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• 제19권1호
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• pp.43-47
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• 2002

The new core making method economizing the amount of core sand has been requested. The new method is that a core box is heated until it reaches reasonable temperature and then core sand with core binder is sprayed into the core box. Since inner temperature distribution have to be uniform in order to form uniform thickness of core, we studied inner temperature distribution of core box. First, we determined proper number of torches and optimized torch positions to minimize the average of absolute deviation(AVEDEV) of inner temperature. The results are as fellowed: 1. The number of torches that enables uniform inner temperature distribution about $300^{\circ}C$ is 25. 2. When $S_H$ and $S_V$ is 0.7, the torch positions are optimized and AVEDEV is 5.85.

• 한국주조공학회지
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• 제42권1호
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• pp.61-66
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• 2022

Hydraulic units are important components of agricultural and construction machinery, and thus require high-quality castings. However, gas defects occurring inside the sand cores of the castings due to the resin used is a problem. This study therefore aimed to develop a casting simulation method that can clarify the gas defect positions. Gas defects are thought to be caused by gas generated after the molten metal fills up the mold cavity. The gas constant is the most effective factor for simulating this gas generated from sand cores. It is calculated by gas generating temperature and analysis of composition in the inert gas atmosphere modified according to the mold filling conditions of molten metal. It is assumed that gases generated from the inside of castings remain if the following formula is established. [Time of occurrence of gas generation] + [Time of occurrence of gas floating] > [Time of occurrence of casting surface solidification] The possibility of gas defects is evaluated by the time of occurrence of gas generation and gas floating calculated using the gas constant. The residual position of generated gases is decided by the closed loops indicating the final solidification location in the casting simulation. The above procedure enables us to suggest suitable casting designs with zero gas defects, without the need to repeat casting tests.

• 농업과학연구
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• 제5권1호
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• pp.29-34
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• 1978

Gun-type nozzle에 있어서 입자(粒子)의 미립화(微粒化)를 개선(改善)코저 절선속도(切線速度)를 증가(增加)하는 방법(方法)의 일환(一環)으로 Screw 중자(中子)를 제작(製作) 장치(裝置)한 Nozzle로 실내(室內)에서 분무실험(噴霧實驗)한 결과(結果) 다음과 같은 결론(結論)을 얻었다. 분무입자(噴霧粒子)의 직경(直徑)이 클수록 분무도달거리(噴霧到達距離)는 컸으며 Screw중자(中子)를 장치(裝置)하였을 때가 장치(裝置)하지 않았을 때에 비(比)하여 분무입자(噴霧粒子)의 미립화(微粒化)는 현저히 양호(良好)하였고 분무도달거리(噴霧到達距離)는 분구(噴口)가 소구경시(小口徑時)에는 거의 차이(差異)가 없었으나 분구(噴口)가 증대(增大)함에 따라서 현저히 짧아졌다. 최고(最高) 도달거리(到達距離) 지점(地點)부터 1~2m의 분무도달거리(噴霧到達距離)에 있어서는 기류부유이동(氣流浮遊移動)의 현상(現象)으로 분무입자(噴霧粒子)가 작아졌다.