디자인을 기초로 한 어린이 미술교육

백종원 한국아동미술학회 2004 학술대회 Vol.2004 No.1

Analysis of a Slab and Slab Heater Cover in a Compact Endless Cast and Rolling Mill Process Using Finite Element Methods

백종원,오주원,정재숙,조용석,박성진 대한금속·재료학회 2019 대한금속·재료학회지 Vol.57 No.1

Compact Endless cast and rolling Mill (CEM) processes were developed and used to fabricate steel products such as steel slabs. However, the coiling furnace in this process was very expensive, so a new layout was suggested. As the coiling furnace was removed, the interval among the slab heaters had to be increased. This led to a temperature drop in the slab. The temperature distribution of the slab impacts quality, so new layout was developed. This paper presents a Finite Element Method (FEM) simulation of thermal behavior in the slab employing slab heater covers. All of the simulation results were verified by comparing them with experimental results. The slab moving distance at which the temperature was saturated during the process was determined to consider the steady-state and analyze the temperature distribution of the slab and slab heater. Those results revealed that the efficiency of heat conservation increased by more than 50% using the slab heater cover. Finally, a sensitivity analysis of the slab heater cover was conducted with respect to the cover design. The effects of insulator thickness, the gap distance between the slab and cover, and material parameters such as density, and specific heat were investigated to optimize the design of the slab heater cover to produce the best quality slab.

Effects of Glycine on the Development of Analgesic Tolerance to and Physical Dependence on Morphine in Mice

백종원,홍진태,윤영원,오기완 한국독성학회 2003 Toxicological Research Vol.19 No.4

This study was performed to investigate the effects of glycine on the development oftolerance to and physical dependence on morphine. Repeated administration of morphine (10 mg/kg) developed tolerance and physical dependence. Glycine (100, 200 and 400 mg/kg) was adminis-tered intraperitoneally (i.p.) to mice for 7 days prior to the morphine injection. Analgesic effects wereestimated by the tail flick methods. The inhibitory degre of the development of morphine-inducedanalgsic tolerance by i.p. administration of glycine was evidenced by the increase in analgesicresponse to morphine. Glycine inhibited the development of tolerance to morphine. In addition, weseparately measured jumping response as the naloxone-precipitated withdrawal sign in mice thathad received the same morphine. Glycine reduced the number of jumping behaviors in morphinedependent mice. These results suggest that glycine might be useful the prevention or treatment ofmorphine tolerance and physical dependence.

고분자의 자체발포를 이용한 세라믹 다공질체

백종원,김득중 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.7

Ceramic foams were prepared by a self-blowing process of a polysiloxane with A1$_2$O$_3$ as a filler. The release of water and ethanol vapor during the condensation reaction of the polymer triggered the pores in the polymer melt. The size. interconnectivity and shape of the pores in the ceramic foams were strongly dependent on the viscosity of the polymer melt, which could be varied by the content and size oi the filler. When the content of the filler inceased and the size of the filler decreased. the size of the pores were decreased and the thickness between the pores were increased. In the addition, the viscosity of polymer melt increased by the pretreatment at 130$^{\circ}C$ for Ire intermolecular cross linking thereby stabilizing the foam structure. The density and compressive strength of the ceramic foams were affected by the heating rate during the blowing process. 폴리실록산 고분자의 자가 발포과정을 이용하여 세라믹 다공질체를 제조하였다. 고분자가 가교반응을 하는 과정에서 발생하는 물과 알콜 증기를 이용하면 고분자 용융액 내에 기공을 형성할 수 있다. 세라믹 다공질체 내의 기공의 크기와 모양은 고분자 용융액의 점도에 따라 크게 달라진다. 충진제인 A1$_2$O$_3$ 함량이 증가하면 기공 크기는 감소하며 이는 A1$_2$O$_3$의 입자크기가 감소하여도 비슷한 양상을 보였다. 고분자 용융액의 점도는 고분자의 가교반응정도에 따라서도 영향을 받는다. 발포 전에 13$0^{\circ}C$에서 열처리를 하면 점도는 증가하며 다공질체의 기공 안정성은 증가한다. 제조된 세라믹 다공질체의 밀도와 압축강도는 발포과정에서의 승온속도에 따라 다른 값을 보였다.

Pressure Transmission in the Compaction Process of Nickel Powder Using the Finite Element Methods

백종원,박성진 대한금속·재료학회 2019 대한금속·재료학회지 Vol.57 No.2

The compression process is one of the more widely used industrial manufacturing methods for fabricating desired shape of specimens with various materials such as metals and ceramics. In the compaction process, the upper punch moves into the powder, and force is transmitted between particles, then achieving densification. In this process, the powder can be considered to be in a particulate state, which means that while the powder consists of solids, it has characteristics quite similar to the fluid. Therefore, particles in the process can be seen as responding to hydrostatic pressure, and it can be assumed that the pressure is constant. However, the forces acted on the inter-particle continue to change during the process. Many parameters affect the force change, including compaction speed and the contact angle between particles. However, it is very difficult to verify these effects through experiments because it is impossible to arrange the inter-particle angle. Therefore, in this study, the force transmission mechanism was simulated in the compaction process using FEM simulation. To examine the contact angle and force transmission between the particles, a green compact was modeled as individual particles rather than as a continuum green compact. Finally, it was confirmed through analysis that the pressure transmission between the particles remained constant during the compression process.

응급실에 내원한 요로결석 환자의 급성 통증 조절에 영향을 미치는 요인

백종원,성원영,이장영,이원석,양영모,서상원 대한응급의학회 2013 대한응급의학회지 Vol.24 No.4

Purpose: The most important step for patients who come to the emergency department with ureter stones is acute pain management. There have been insufficient studies on what factors affect acute pain management for ureteral colic the most. In this study, patients with ureteral colic were divided into two groups: one group, in which the pain was first managed with an analgesic, and another group with unmanaged pain, to find factors that most affect additive analgesics administration for ureter stones. Methods: There were 121 patients, eventually confirmed for the presence of ureter stones through a computed tomography CT scan, included in this study. When ureter stones were suspected after the initial patient evaluation,initial pain was assessed through numerical rating scale (NRS) and the first analgesic was administered once. Pain was reassessed through NRS after 30 minutes. At that time, if the pain was managed, the patient was assigned to Group 1. If the pain persisted, another analgesic was administered for the second and third time, and the patient was assigned to Group 2. Finally, ureter stones were identified through CT scan. Results: There were 58 patients (47.9%) in Group 1 and 63 patients (52.1%) in Group 2. There were no statistically significant differences in average age, serum creatinine,size of ureter stone, and severity of hematuria between the two groups. The differences in NRS measured initially and after 30 minutes were statistically significant (7.6±1.4 vs. 8.6±1.2, p<0.001; 1.4±1.3 vs. 6.6±1.9, p<0.001, respectively). The presence of hydronephrosis and perirenal edema were also statistically significant (p<0.001, p=0.007). The affecting factor for the administration of additive analgesics was hydronephrosis (odds ratio 7.213, p<0.001). Conclusion: Hydronephrosis is an important factor in the treatment of patients with additive analgesics. It can also be used as a predictive index to assess the severity of pain in patients with ureter stones.

경기 관람에 영향을 미치는 요인에 관한 선행연구 고찰

백종원 서울대학교 스포츠과학연구소 2014 스포츠과학리뷰 Vol.8 No.2

본 연구의 목적은 경기장 관람에 영향을 미치는 요인들에 대한 선행연구 고찰을 통해 서 경기 연맹 실무자들에게 스포츠 이벤트 활성화를 위한 기초자료를 제공하기 위한 것이다. 선행 연구 고찰 결과 스포츠 경기 관람에 영향을 주는 요인 가운데 선수 요인 과 팀 요인, 주말 경기 요인은 관람객 증가에 긍정적으로 작용하였다. 한편 텔레비전 중계방송 요인은 경기장 관람객 증가에 부정적인 요인으로 나타났다. 경기 관람에 영 양을 주는 다른 요인들은 경기 종목과 연구자에 따라 상반되는 결과를 보이고 있었다 The purpose of this study was to survey the sports attendance literature to get the factors which affect sport spectators. The result of this study reveals that the factors which spur game-day attendance were star players, high team quality and team ranking, and the kickoff time. On the other hand, television broadcasting reduces attendance.

골프 코칭 서비스품질에 관한 분석

백종원 서울대학교 스포츠과학연구소 2014 스포츠과학리뷰 Vol.8 No.1

본 연구의 목적은 골프 코치의 서비스 품질이 아마추어 골프 레슨 소비자들의 코치 선택에 어떻게 영향을 주는지를 알아보기 위한 것이다. 연구를 위한 설문조사는 SNS 를 통해 스노우볼 샘플링 방식으로 진행되었다. 최초 설문지 500부는 구글 독스 (Google docs.)를 통해 서울 소재의 한 골프연습장 회원에게 배포되었으며 설문조사 응답자에게 SNS를 통해 지인에게 설문지를 전달해 줄 것을 부탁하였다. 회수된 204부 의 설문지를 SPSS20.0을 통해서 통계적 분석을 실시하였으며 그 결과는 다음과 같다. 첫째, 아마추어 골퍼들의 코치 선택에 영향을 주는 요인은 코치의 성품, 친교/사교, 코 칭 능력 그리고 코치가 근무하는 근무지의 환경이었다. 이상 4가지 요인은 아마추어 골퍼들의 골프 코치선택에 68.8%까지 영향을 주었다. 둘째, 아마추어 골퍼들의 골프레 슨 참여 동기와 인구통계학적 요인은 골프 코치 선택에 거의 영향을 미치지 못했다. The purpose of this study was to find relationship between golfer's behavior in choosing their golf coach and the coacher's service quality. Snowball sampling was conducted for this study by SNS. Initially 500 questionnaires were given out to armature golfers in P golf range in Seoul through Google docs. Researchers also asked to participants to pass the questionnaires down to their friends through SNS. The total of 204 questionnaires were used for this study. As for statistical data analysis, factor analysis, t-test were conducted using SPSS 20.0. The result of this study were as followed. First, The factors that affect to armature golfers in choosing their golf coach are coach's personality, social network, coaching ability, and the facility where the coach works. These four factors affect up to 68.8% when armature golfers choose their golf coach. Second, motivations in participating golf lesson and demographic factors give very little affect to golfers in choosing their golf coach.

GIS를 이용한 교통 계획과 교통량 분석에 관한 연구

백종원 강원대학교 토목공학과 지구공간정보연구실 1993 지구공간정보공학연구 Vol.1 No.-

선택적 척추주위근 위축으로 인한 배굴증

백종원,김미애,손영호,강석윤 대한신경과학회 2008 대한신경과학회지 Vol.26 No.2