[연료 및 윤활유부문] 엔진 베어링에서의 공기 혼입 윤활유의 하중 지지력에 관한 연구

박영환(Younghwan Park),장시열(Siyoul Jang) 한국자동차공학회 2001 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2001 No.11_1

This work analyzes the behaviors of aerated lubricant in the gap between con-rod bearing and journal. Aerated lubricant influences two major factors on the film formation. One is the density characteristics of the lubricant due to the volume change by the bubbles and the other is the viscosity characteristics of the lubricant due to the surface tension of the bubble. Those two major factors surprisingly increase the load capacity in certain ranges of bubble sizes and densities. Modified Reynolds' equation is developed with the consideration of aerated ratio in the lubricant and journal locus is computed with Mobility method with the computation of two dimensional pressure distribution over the bearing area.

이동 로봇의 주행 정보 정밀도 향상을 위한 바퀴에 작용하는 힘 추정

박영환(Younghwan Park),이지홍(Jihong Lee) 대한전기학회 2020 정보 및 제어 심포지엄 논문집 Vol.2020 No.10

從魯認『錦溪日記』的記錄看端午文化地域特徵與多元性

朴永煥 ( Park Younghwan ) 중국어문학회 2020 中國語文學誌 Vol.0 No.71

In general, the Dragon Boat Festival in China is outlined as May 5th, QuYuan, JingDu math: ‘dragon boat race’, ‘Eat Zongzi’ to celebrate him. However, if we take a look at ancient literature records, including the Chinese provinces, it reveals that there is a significant difference from this perception. GeumKye Diary by No-In, who escaped from Japan in Wanli 27(1599) and came to Fujian Province, vividly describes Fujian’s tradition of Dragon Boat Festival from the late 16th century in detail. However, the content goes beyond the common sense that we know about. First, the Dragon Boat Festival does not start on May 5th. It begins on May 1st, some regions even hold events until May 15th. Second, in the southern part of China, during the Dragon Boat Festival, people do ‘dragon boat race’ and Zongzi throwing, whereas the northern part of the country calls the Dragon Boat Festival ‘Girl’s Day,’ mainly performing walk activities. Third, during Korean-Chinese Dragon Boat Festival, Korea holds memorial activities for 500 righteous ancestors, including Tian Heng. It has nothing to do with QuYuan. Lastly, Fujan’s emphasis on the Dragon Boat Festival overwhelms other holidays. In conclusion, through GeumKye Dairy by No In, one can grasp pluralism and abundance of the Dragon Boat Festival in each Chinese region, uniqueness of Korean-Chinese Dragon Boat Festival, and trends of the Dragon Boat Festival, which are significantly helpful in grasping the contents of the different Dragon Boat Festival traditions in each era.

차량 좌석 대용 휠체어의 강도 시험법에 관한 연구

박영환(Younghwan Park),홍정화(Junghwa Hong),김경훈(Kyunghoon Kim),이인혁(Inhyuk Lee) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

As the number of wheelchair users increases, the safety of the wheelchair user is becoming a big concern. An increasing number of wheelchair users use their wheelchairs as motor vehicle seats when traveling. A standard requires that compliant wheelchairs be dynamically sled impact tested. However, testing to evaluate the crashworthiness of wheelchair seating systems (WCSS) independent of their wheelchair wheel is not addressed by this standard, To address this need, this study developed a method to evaluate the crashworthiness of WCSS with independent wheels using computer simulation. To secure the safety, minimum strength requirements for the wheelchair are proposed based on the Federal Motor Vehicle Safety Standard (FMVSS) 207 regulation for the normal seats used in the vehicle. This test protocols, used to test the strength of motor vehicle seats, were modified and used to test the strength of wheelchair frame. Forward and rearward loads were applied at the WCSS center of gravity (CGSS), and a moment was applied at the uppermost point of the seat back. From the simulation, we could know a stress distribution by the applied load. As the result of this study, presents the criteria to minimize the injury of the wheelchair passenger and provides design guidelines to the manufacturers of wheelchair.

해군 함정 레이더 디스플레이의 EID(Ecological Interface Design)를 위한 WDA(Work Domain Analysis) 적용

박영환(Younghwan Park),명노해(Rohae Myung) 한국HCI학회 2011 한국HCI학회 학술대회 Vol.2011 No.1

국외소재 고려시대 청동정병의 과학적 보존처리 -벨기에 왕립예술역사박물관 소장 유물을 중심으로-

박영환 ( Park Younghwan ),이재성 ( Lee Jaesung ) 공주대학교 문화재보존과학연구소 2022 문화재과학기술 Vol.17 No.1

한국-벨기에 수교 120주년을 기념하여 벨기에 왕립예술역사박물관에서 소장하고 있던 청동정병을 보존처리하였다. 청동정병은 군지형 정병으로 첨수대의 뚜껑이 개폐가 가능한 상태였다. 첨대의 주구 부분이 일부 결실되고 동체부의 보수 흔적이 있으며, 첨수대가 동체에 접합된 상태였다. 표면으로는 일부 부식물이 형성되어 있으나 안정한 상태로 보관 관리가 되었던 것으로 확인되었다. 청동정병은 구리-주석-납의 청동 합금을 주조하여 형태를 만들고, 따로 제작한 첨수대를 동체에 부착하고, 바닥면에 청동원판을 결합하는 과정으로 정병을 제작하였다. 또한 자외선, X선 등 비파괴 조사를 통해서는 합성수지로 보수한 흔적을 찾을 수 있는데, 청동정병의 동체부 상단과 바닥면 그리고 첨수대에서 보수한 흔적이 관찰된다. CT조사 결과 보수한 부분은 경미한 결함을 보수한 것으로 확인되었고, 수직 단면이 좌우 대칭처럼 일정하고 기벽의 두께도 일정한 부분은 정병을 정교하게 제작하기 위해 노력한 것으로 보인다. 청동정병과 보수 재료의 상태는 비교적 양호한 것으로 판단되어 보수 재료의 제거없이 원 형태를 유지하되 주구부의 결실 부분은 복원하는 방향으로 보존처리를 진행하였다. 결실부의 복원은 에폭시계 복원제를 주 재료로 제작하고, 이를 가역성이 있는 셀룰로오스계 접착제를 사용하여 접합함으로써 추후 쉽게 제거가 가능하도록 하였다. In commemoration of the 120th anniversary of the diplomatic relations between the Republic of Korea and the Kingdom of Belgium, the scientific conservation treatment for the bronze Kundika (a Buddhist ritual ewer) which has been kept in the collection of Royal Museums of Art and History (RMAH), Belgium was conducted. The bronze Kundika belongs to the type of Kunji(軍持) ewer and the lid of its spout is possible to be opened and closed. The mouth of its nozzle was partially missing and there were traces to have been restored in the past on the body where the spout was attached. Some corrosion products have been situated on the surface and however, it was identified to have been maintained under stable conditions for storage. This Kundika was manufactured by bronze alloying with Cu-Sn-Pb and the spout was separately crafted and attached to the body, and finally the round base was connected to the bottom. In addition, some traces to have been restored with synthetic resins in the past were found through the non-destructive analysis such as UV irradiation and X-ray photography, revealing traces from the upper part and base of the body as well as the spout. As a result of CT scan, formerly restored areas were identified to have been treated for minor flaws, and the symmetric vertical cross section and constant thickness of the wall indicated that efforts were made to manufacture the Kundika sophisticatedly. Based on that the condition of the Kindika and restoration materials used were judged to be relatively good, the conservation treatment was carried out in the manner of restoring missing areas on the mouth, keeping the original form without removing formerly used restoration materials. For the restoration of missing areas, epoxy-typed restoration materials were prepared as the main material and the reversible cellulose adhesives were used for connection, which will facilitate removal of adhesives easily in the future when necessary.

歐陽脩와 禪宗과의 交遊

박영환(Park, Younghwan) 國際言語文學會 2014 國際言語文學 Vol.- No.29

중국에서 한국어교육의 효율적 방안

박영환(Park Younghwan) 한국언어문학회 2007 한국언어문학 Vol.60 No.-

  This paper deals with the effective ways for teaching Korean to the students in China.<BR>  These efficient methods can be found in the five fields connected with teaching Korean.<BR>  They are building the teachers, reforming the curricula, publishing the textbooks, developing the teaching skills and changing the evaluating systems.<BR>  In the every field I suggest many successful ways concretely in order to satisfy the goal that the Chinese students can learn Korean easily, satisfactorily and effectively.<BR>  For example, in the part of the development and publication of the textbooks seven ideas are suggested as follows.<BR>  ① We should study deeply for publishing the useful textbooks.<BR>  ② Group researches can be more effective than the personal ones.<BR>  ③ Motivation and equivalence are very important.<BR>  ④ Many sorts of books should be published according to the user’s levels or needs.<BR>  ⑤ Korean textbooks must have the connection with the Korean culture.<BR>  ⑥ Handouts or guide books are needed to the teachers or the learners.<BR>  ⑦ We have to make sufficient programs for the learners to use multimedia.<BR>  By way of experiencing these elementary methods, I hope that most of students in China can learn Korean efficiently.

叶适的屈骚观研究

朴永煥(Park YoungHwan) 한국중어중문학회 2008 中語中文學 Vol.42 No.-

YeShi who represents the latter South-Song dynasty the world of thought are emphasizing the practicality and a utility of study. Consequently YeShi from the side of utility as prejudice is criticizing the evaluation which is negative about QuYuan of Han dynasty scholar. Therefore Yeshi is evaluating QuYuan's personality and a moral character very affirmatively from the side of utility At the same time, He is taking a serious view of the formal beauty of a sentence. It points that YeShi recognizes an aesthetic effect of the literature enough. His point of view like this is beautiful and splendid characteristic. And his point of view just reflects it in evaluation of QuYuan's literary work which is full of imagination. Though South-Song dynasty's people down played a sentence. he is different from them. A claim for his literature is very precious. Therefore. he affected out look on literature of other people directly, and he gave big influence in the time.

환자 SET-UP ERROR에 따른 선량분포와 DVH 변화 분석

김경태,주상규,안재홍,박영환,Kim KyoungTae,Ju SangGyu,Ahn JaeHong,Park YoungHwan 대한방사선치료학회 2004 大韓放射線治療技術學會誌 Vol.16 No.2

Introduction : The setup error due to the patient and the staff from radiation treatment as the reason which is important the treatment record could be decided is a possibility of effect. The SET-UP ERROR of the patient analyzes the effect of dose distribution and DVH from radiation treatment of the patient. Material & Methode : This test uses human phantom and when C-T scan doing, It rotated the Left direction of the human phantom and it made SET-UP ERROR , Standard plan and 3mm, 5mm, 7mm, 10mm, 15mm, 20mm with to distinguish, it made the C-T scan error. With the result, The SET-UP ERROR got each C-T image Using RTP equipment It used the plan which is used generally from clinical - Box plan, 3Dimension plan( identical angle 5beam plan) Also, ( CTV+1cm margin, CTV+0.5cm margin, CTV+0.3,cm margin = PTV) it distinguished the standard plan and each set-up error plan and The plan used a dose distribution and the DVH and it analyzed Result : The Box4 the plan and 3Dimension plan which it bites it got similar an dose distribution and DVH in 3mm, 5mm From rotation error and Rectilinear movement( $0\%{\sim}2\%$ ). Rotation error and rectilinear error 7mm, 10mm, 15mm, 20mm appeared effect it will go mad to a enough change in treatment ( $2\%{\sim}^11\%$ ) Conclusion : The diminishes the effect of the SET-UP ERROR must reduce move with tension of the patient Also, we are important accessory development and the supply that it reducing of reproducibility and the move 목적 : 방사선 치료에서 환자와 근무자에 의한 setup error등은 치료성적이 결정될 수 있는 중요한 요인이라고 볼 수 있다. 이에 환자와 근무자에 의한 SET-UP ERROR가 환자치료에 미치는 영향에 대하여 비교 분석하고자 한다. 대상 및 방법 : 실험은 human phantom을 이용하여 C-T scan시 Left방향의 Lateral Level을 0mm, 3mm, 5mm, 7mm, 10mm, 15mm, 20mm로 변화시켜 SET-UP ERROR를 유발하였고, 각각에 대하여 C-T scan을 시행하였고, SET-UP ERROR가 유발된 각각의 C-T image를 얻어 RTP장비를 이용하여 임상에서 많이 사용되는 plan을 사용하여 7개의 C-T image에 각각의 plan-대향이문조사plan, Box-4문조사plan, 3Dimension plan-3개를 시행하여 총 21개의 plan을 실시하였다. (CTV+1cm margin, CTV+0.5cm margin, CTV+0.3cm margin = PTV) 이렇게 얻어진 plan을 이용하여 SET-UP ERROR가 유발이 안된 0mm image의 plan 3개와 SET-UP ERROR가 있는 6개 image의 총 18개의 plan을 대향이문조사plan, Box4문조사plan, 3Dimension plan으로 나누어 선량분포와 DVH를 이용하여 비교 분석하였다. 결과 : SET-UP ERROR를 유발시킨 3mm, 5mm, 7mm C-T image에서는 대향이문조사plan을 제외하고는 모든 plan에서 충분히 치료에 영향을 미칠만한 변화가 나타났으며, Box4문조사plan에서는 SET-UP ERROR에 의한 CTV가 Field 밖으로 빠짐으로 선량분포와 DVH가 나빠지는 현상이 나타났다. 결론 : 환자의 움직임, CTV 3차원형태, CTV margin등이 치료에 영향을 미친다. 이러한 영향을 줄이기 위해서는 환자의 긴장감과 움직임을 줄일 수 있는 환자교육과 정확한 환자setup능력이 치료의 승패를 좌우한다고 생각된다. 또한 재현성과 움직임을 줄일 수 있는 accessory 개발과 보급이 중요하다.