금속쐐기와 기능강화동적쐐기의 조사야 주변부 선량 비교

박종민,김희정,민제순,이제희,박찬일,예성준,Park, Jong-Min,Kim, Hee-Jung,Min, Je-Soon,Lee, Je-Hee,Park, Charn-Il,Ye, Sung-Joon 한국의학물리학회 2007 의학물리 Vol.18 No.3

방사선 방호의 측면에서 기능강화동적쐐기가 금속쐐기에 비하여 가지는 이점을 평가하기 위하여 각각의 쐐기에서 산란되는 조사야 주변부 선량을 측정하였다. 측정 장비는 2D Array를 사용하였고 장비의 신뢰성을 검증하기 위하여 측정값과 치료계획장치에서 계산된 결과를 비교하였다. $15^{\circ},\;30^{\circ},\;45^{\circ},\;60^{\circ}$의 금속쐐기와 기능강화동적쐐기를 사용하였을 때에 선원표면간거리를 80 cm에서 90 cm로 변화시키며 조사야 주변부의 선량백분율을 측정하였다. 광자선의 에너지는 6 MV와 15 MV를 사용하였다. 측정은 0.5 cm 깊이에서 조사야 경계로부터 1 cm부터 5 cm까지 1 cm 간격으로 이루어졌다. 열형광선량계를 사용하여 절대 선량을 측정하였다. 2D Array를 사용하여 측정하였을 경우, 기능강화동적쐐기를 사용하였을 때의 조사야 주변부 선량백분율($1.4%{\sim}11.9%$)이 금속쐐기를 사용하였을 때($2.5%{\sim}12.4%$)에 비하여 낮았다. 15 MV의 에너지를 사용했을 경우에 6 MV의 에너지를 사용했을 경우보다 조사야 주변부 평균 선량백분율이 2.9% 높았다. 선원표면간거리가 80 cm일 경우에 90 cm일 경우보다 선량백분율의 차이를 분명히 확인할 수 있었다. 쐐기의 Heel 방향의 선량백분율이 Toe방향의 선량백분율보다 평균적으로 0.9% 낮았다. 열형광선량계를 이용한 절대 선량 측정에서도 2D Array를 사용하여 측정한 경우와 합치하는 결과가 나왔다. 기능강화동적쐐기는 임상에서 조사야 주변부의 정상조직에 불필요하게 산란되어 전달되는 선량을 감소시켜준다. 이러한 이점은 쐐기의 각도가 증가하고 선원표면간거리가 감소할수록 더욱 부각된다. In order to evaluate the radio-protective advantage of an enhanced dynamic wedge (EDW) over a physical wedge (PW), we measured peripheral doses scattered from both types of wedges using a 2D array of ion-chambers. A 2D array of ion-chambers was used for this purpose. In order to confirm the accuracy of the device we first compared measured profiles of open fields with the profiles calculated by our commissioned treatment planning system. Then, we measured peripheral doses for the wedge angles of $15^{\circ},\;30^{\circ},\;45^{\circ},\;and\;60^{\circ}$ at source to surface distances (SSD) of 80 cm and 90 cm. The measured points were located at 0.5 cm depth from 1 cm to 5 cm outside of the field edge. In addition, the measurements were repeated by using thermoluminescence dosimeters (TLD). The peripheral doses of EDW were (1.4% to 11.9%) lower than those of PW (2.5% to 12.4%). At 15 MV energy, the average peripheral doses of both wedges were 2.9% higher than those at 6MV energy. At a small SSD (80 cm vs. 90 cm), peripheral dose differences were more recognizable. The average peripheral doses to the heel direction were 0.9% lower than those to the toe direction. The results from the TLD measurements confirmed these findings with similar tendency. Dynamic wedges can reduce unnecessary scattered doses to normal tissues outside of the field edge in many clinical situations. Such an advantage is more profound in the treatment of steeper wedge angles, and shorter SSD.

침수피해에 의한 벼 감수량 추정기법 개발

박종민,김상민,성충현,박승우,Park , Jong-Min,Kim , Sang-Min,Seong, Chung-Hyun,Park, Seung-Woo 한국농공학회 2004 한국농공학회논문집 Vol.46 No.5

The amount of rice yield reduction due to inundation should be estimated to analyse economic efficiency of the farmland drainage improvement projects because those projects are generally promoted to mitigate flood inundation damage to rice in Korea. Estimation of rice yield reduction will also provide information on the flood risk performance to farmers. This study presented the relationships between inundated durations and rice yield reduction rates for different rice growth stages from the observed data collected from 1966 to 2000 in Korea, and developed the rice yield reduction estimation model (RYREM). RYREM was applied to the test watershed for estimating the rice yield reduction rates and the amount of expected average annual rice yield reduction by the rainfalls with 48 hours duration, 10, 20, 50, 100, 200 years return periods.

항통을 주소로 내원(來院)한 크론병(Chron's disease) 호전 1례

박종민,김호준,금동호,박영회,이명종,Park, Jong-Min,Kim, Ho-Jun,Keum, Dong-Ho,Park, Young-Hoi,Lee, Myeong-Jong 척추신경추나의학회 2010 척추신경추나의학회지 Vol.5 No.1

항통을 주소로 내원한 환자의 크론병에 대한 침구(鍼灸)치료로 복통 및 설사의 관해 상태가 되는 양호한 효과를 얻었기에 보고하는 바이다. 다만, 치료 기간이 짧아 증상의 변화의 추적이 필요한 상태이며, 다양한 임상적 연구를 위한 임상사례 데이터가 축적되어야 할 것으로 사료된다. Objective: This study evaluated the effects of Oriental treatments on one patient who was diagnosed to Crohn's disease. Methods: One patient was diagnosed as Crohn's disease by physician. We used acupuncture and moxibustion at 曲池(LI11), 天樞(S25), 足三里(ST36), 合谷(LI4) and (GL25), 2 times per week about one month. We analyzed the change symptom by Crohn's disease activity index(Harvey-Bradshaw index) before and after treatment. Results: After treating acupuncture and moxibustion in the case, We found out that the Crohn's disease activity index score was significantly improved after treatment. First the number of liquid or very soft stool was decreased to 2 times a day and the stools became more solid condition. The abdominal pain and use of anti-diarrhea medication score came to none. The well being score set slightly below poor condition. Conclusions: These result suggest acupuncture, moxibustion were effective to Crohn's disease clinical symptom. These could help patient ordinary life by reducing abdominal pain and diarrhea.

란탄족 원소의 전기화학적 환원에 관한 연구 (제 1 보)

박종민,강삼우,도이미,한양수,손병찬,Park, Jong Min,Gang, Sam U,Do, Lee Mi,Han, Yang Su,Son, Byeong Chan 대한화학회 1990 대한화학회지 Vol.34 No.6

수용액에서 가벼운 란탄족 금속이온의 전기화학적 거동을 직류 폴라로그래피, 펄스차이 폴라로그래피 및 순환 전압전류법으로 연구하였다. La$^{3+}$, Pr$^{3+}$ 및 Nd$^{3+}$의 환원은 0.1 M LiCl 지지전해질에서 3전자가 관여하는 비가역적인 반응이었다. Sm$^{3+}$의 환원은 0.1 M TMAI 지지전해질에서 1전자에 이어 2전자가 관여하는 비가역적인 반응이었으며, Eu$^{3+}$의 환원은 0.1 M LiCl 지지전해질에서 1전자에 이어 2전자가 관여하는 유사가역반응 및 비가역반응이었다. 펄스차이 폴라로그래피에 의하면 pH 4 이하에서는 수소이온의 촉매효과에 의하여 가수분해된 란탄족 금속이온 (Ln(OH)$^{2+}$)은 란탄족 금속이온(Ln$^{3+}$)보다 양전위에서 환원되었으며, 봉우리 전류의 크기는 Eu$^{3+}$ < Sm$^{3+}$ < Nd$^{3+}$ < Pr$^{3+}$ < La$^{3+}$ 순으로 증가하였다. 순환 전압전류법에서 주사속도 변화에 대한 전류함수의 크기는 [H$^{+}$]/[Ln$^{3+}$]의 비에 의존하였으며, pH 및 란탄족 금속이온의 농도가 낮을수록 수소이온에 의한 반응 또는 촉매전류가 증가하였다. Voltammetric behavior of some light lanthanide ions (La$^{3+}$, Pr$^{3+}$, Nd$^{3+}$, Sm$^{3+}$, and Eu$^{3+}$) in various supporting electrolytes has been investigated by several electrochemical techniques. The peak potentials and the peak currents, their dependency on the concentration, temperature and pH effects, the reversibility of the electrode reactions are described. The reduction of La$^{3+}$, Pr$^{3+}$ and Nd$^{3+}$ in 0.1 M lithium chloride proceeds by a three-electron change directly to the metallic state (Ln$^{3+}$ + 3e- → Ln$^0$) and charge transfer is totally irreversible. However, the reduction of Sm$^{3+}$ in 0.1 M tetramethylammonium iodide and Eu$^{3+}$ in 0.1 M lithium chloride proceeds in two stages (Ln$^{3+}$ + e- → Ln$^{2+}$ and Ln$^{2+}$ + 2e- → Ln$^0$). At pH values lower than ca.4 the hydrated lanthanide species (Ln(OH)$^{2+}$) reduced before the lanthanide ions (Ln$^{3+}$) due to the catalytic effect of hydrogen ions, and peak current increase with in the order Eu$^{3+}$ < Sm$^{3+}$ < Nd$^{3+}$ < Pr$^{3+}$ < La$^{3+}$ in differential pulse polarography. Some representative plots of $i_{pc}V^{-1/2} (proportional to current function) vs. V show considerable influence of hydrogen ion/lanthanide ion concentration in cyclic voltammetry. It is shown that a reaction of lanthanide ions with proton and/or water and catalytic reaction is enhanced at lower pH and at decreased lanthanide ion concentration.

The Password base System for the safe and Efficient Identification

박종민,박병전,Park, Jong-Min,Park, Byung-Jun The Korea Institute of Information and Commucation 2009 한국정보통신학회논문지 Vol.13 No.1

Almost all network systems provide an authentication mechanism based on user ID and password. In such system, it is easy to obtain the user password using a sniffer program with illegal eavesdropping. The one-time password and challenge-response method are useful authentication schemes that protect the user passwords against eavesdropping. In client/server environments, the one-time password scheme using time is especially useful because it solves the synchronization problem. In this paper, we propose a new identification scheme One Pass Identification. The security of Password base System is based on the square root problem, and Password base System is secure against the well known attacks including pre-play attack, off-line dictionary attack and server comprise. A number of pass of Password base System is one, and Password base System processes the password and does not need the key. We think that Password base System is excellent for the consuming time to verify the prover. 사용자 고유번호와 패스워드 기반의 사용자 인증 매커니즘을 수행하는 네트워크 시스템 환경에서는 스니퍼 프로그램 등을 이용하여 불법 도청함으로써 쉽게 사용자의 패스워드를 알아낼 수 있다. 이러한 불법적인 도청에 의한 패스워드 노출 문제를 해결하는 방법으로 일회용 패스워드, Challenge-Response 인증 방식이 유용하게 사용되며, 클라이언트/서버 환경에서는 별도 동기가 필요 없는 시간을 이용한 일회용 패스워드 방식이 특히 유용하게 사용될 수 있다. 본 논문에서는 안전성은 Square root problem에 기초를 두고 있고, 프리플레이 공격, 오프라인 사전적 공격 그리고 서버 등을 포함하여 지금까지 잘 알려진 공격(해킹)들에 대해서 안전성을 높이기 위한 암호기반 시스템을 제안한다. 암호기반 시스템 확인은 패스워드를 생성하는데 특별한 키를 생성할 필요가 없다는 것이다. 암호기반 시스템은 검증자를 확인하는데 걸리는 시간이 적게 소요되면서 특출하다.

벌크화물용 포장용기의 최적 설계(I)-알고리즘 개발

박종민,권순구,Park, Jong-Min,Kwon, Soon-Goo 한국포장학회 2000 한국포장학회지 Vol.6 No.1

In optimum design of packaging container for bulk materials, minimum board area, compression performance and distribution efficiency must be considered. In this study, mathematical models for minimum board area (RMA), compression strength (CS) and maximum compression strength per unit board area (MCSA) of container as algorithm for optimum design of packaging conatiner for bulk materials were developed as follows : RMA=f(V,D), ${\alpha}_{RMA}=f(V,D)$, MCSA=f(V,D), and ${\alpha}_{MCSA}=f(V,D)$. In order to develop these models, compression test according to various dimensions of container and response surface analysis for minimum board area, compression strength, and maximum compression strength per unit board area of container were carried out. In developed models, volume and depth of container were principal independent variables. Through the verified results for these models, optimum design of packaging container on the design conditions and limit conditions was possible. These models might be used in developing optimum design software of packaging container for bulk materials.

농업협동조합 개혁

박종민,Park Jong Min 한국관개배수위원회 2004 한국관개배수논문집 Vol.11 No.2

통기성 상자 구조물의 강도적 최적화 연구(I)-실증 분석

박종민,Park, Jong-Min 한국포장학회 2001 한국포장학회지 Vol.7 No.2

현재 국내에는 통기성 상자의 설계에 관한 기준이 마련되어 있지않아, 통기공으로 인한 상자 압축강도 저하와 통기성 면에서도 좋지 않은 형편이다. 선진 외국과는 물류 및 포장환경이 다르고, 방법에 있어서도 큰 차이가 있기 때문에 외국의 사례를 국내의 포장설계에 적용하는 데는 한계가 있다. 따라서 본 연구는 현재 국내에서 유통되는 통기성 상자에 대한 실태분석과 온 습도 변화에 따른 압축강도 저하와 통기성을 분석하므로써, 통기성 상자의 최적설계를 위한 설계 기준을 마련하고자 수행되었다. 현행 유통되는 통기성 상자의 통기공의 면적 비율은 $1.41{\sim}2.65%$ 였으며, 통기공의 형태, 크기 및 위치가 매우 다양하여, 이로 인한 상자 압축강도 저하율은 $8.5{\sim}20.2%$의 범위에 있었다. 대체로 통기공의 면적비율 보다는 통기공의 형태와 위치가 상자의 압축강도 저하에 미치는 더 중요한 요인으로 분석되었다. 통기공의 면적비율이 클 수록 온도와 상대습도의 평형도달시간은 짧았으며, 온도가 상대습도에 비하여 더 빨리 형평상태에 도달하였으며, 또한 통기공의 면적 비율이 같은 경우, 통기공의 형태에 따른 온도 및 상대습도의 평형도달 시간과 평형도달 온 습도에 있어서는 큰 차이가 없었다. The design criteria of ventilating container is not provided yet in Korea. This caused strength reduction due to the ventilating hole and bad ventilating performance. The purposes of this study were to survey the present situation of ventilating container in Korea, to analyze the strength reduction on the atmosphere condition variation, and to provide the criteria for the optimum design of ventilating container. The ventilating area of container was $1.41{\sim}2.65%$, and strength reduction due to the varied pattern, size and location of ventilating hole was $8.5{\sim}20.2%$. The effect on the strength reduction from the pattern and location of ventilating hole was bigger than that from the ventilating area. Equilibrium arrival time of temperature and relative humidity was shorter as the ventilating area was bigger, and temperature reached to the equilibrium state earlier than the relative humidity. There was no significant difference on the ventilating hole pattern between equilibrium arrival time of temperature and relative humidity and equilibrium arrival temperature and relative humidity if the ventilating area was the same.

종이성형구조물의 휨강성에 대한 실험적 연구

박종민,이명훈,Park, Jong-Min,Lee, Myung-Hoon 한국포장학회 1999 한국포장학회지 Vol.5 No.2

Top-to-bottom compression strength of corrugated fiberboard boxes is partly dependent on the load-carrying ability of the central panel areas. The ability of these central areas to resist bending under load will increase the stacking strength of the box. The difference of box compression strengths, among boxes which are made with identical dimensions and fabricated with same components but different flute sizes, is primarily due to difference of the flexural stiffness of the box panels. Top-to-bottom compression strength of a box is accurately predicted by flexural stiffness measurements and the edge crush test of the combined boards. This study was rallied out to analyze the flexural stiffness, maximum bending force and maximum deflection for various corrugated fiber-boards by experimental investigation. There were significant differences between the machine direction (MD) and the cross-machine direction (CD) of corrugated fiberboards tested. It was about 50% in SW and DW, and $62%{\sim}74%$ in dual-medium corrugated fiberboards(e.g. DM, DMA and DMB), respectively. There were no significant differences of maximum deflection in machine direction among the tested fiberboards but, in cross direction, DM showed the highest value and followed by SW, DMA, DMB and DW in order. For the corrugated fiberboards tested, flexural stiffness in machine direction is about $29%{\sim}48%$ larger than cross direction, and difference of flexural stiffness between the two direction is the lowest in DMA and DMB.

농업$\cdot$농촌 용수 종합이용계획

박종민,Park Jong-min 한국관개배수위원회 1999 한국관개배수논문집 Vol.6 No.2