철도사고 대피경로 탐색을 위한 다수상품 유통문제와 최단경로 해법 연구

장병만(Byung Man Chang),김시곤(Si-Gon Kim) 한국철도학회 2007 한국철도학회논문집 Vol.10 No.5

유방향의 복수 최단 경로 문제 해법 연구

장병만(Chang, Byung Man),민윤홍(Min, Yoon Hong) 대한산업공학회 2008 대한산업공학회 춘계학술대회논문집 Vol.2008 No.5

This paper presents a new algorithm procedure for the K shortest path problem in a directed network. After a shortest path is produced with Dijkstra algorithm, detouring paths through inward arcs to every vertex of the shortest path are generated. A length of a detouring path is the sum of both the length of the inward arc and the difference between the shortest distance from the origin to the head vertex and that to the tail vertex. K-1 shorter paths are selected among the detouring paths and put into the set of K paths. Then detouring paths through inward arcs to every vertex of the second shortest path are generated, and the K paths are selected and rearranged in the ascending order of lengths. This procedure of generating the detouring paths and rearranging the set is repeated for the K-1st path of the set. A computational result is suggested to show an efficiency of this procedure. This algorithm can be applied to a problem of generating the detouring paths for ITS and network routing problems.

유방향의 복수 최단 경로 문제 해법 연구

장병만(Chang, Byung Man),민윤홍(Min, Yoon Hong) 한국경영과학회 2008 한국경영과학회 학술대회논문집 Vol.2008 No.5

This paper presents a new algorithm procedure for the K shortest path problem in a directed network. After a shortest path is produced with Dijkstra algorithm, detouring paths through inward arcs to every vertex of the shortest path are generated. A length of a detouring path is the sum of both the length of the inward arc and the difference between the shortest distance from the origin to the head vertex and that to the tail vertex. K-1 shorter paths are selected among the detouring paths and put into the set of K paths. Then detouring paths through inward arcs to every vertex of the second shortest path are generated, and the K paths are selected and rearranged in the ascending order of lengths. This procedure of generating the detouring paths and rearranging the set is repeated for the K-1st path of the set. A computational result is suggested to show an efficiency of this procedure. This algorithm can be applied to a problem of generating the detouring paths for ITS and network routing problems.

공공차량 경로문제의 이중 최단나무 결합 해법

장병만(Byung-Man Chang) 대한산업공학회 1990 대한산업공학회지 Vol.16 No.2

복수 최단 경로의 새로운 해법에 관한 연구

장병만(Byung Man Chang) 한국경영과학회 2008 經營 科學 Vol.25 No.2

This paper presents a new algorithm for the f{ shortest paths problem in a network. After a shortest path is produced with Dijkstra algorithm, detouring paths through inward arcs to every vertex of the shortest path are generated. A length of a detouring path is the sum of both the length of the inward arc and the difference between the shortest distance from the origin to the head vertex and that to the tail vertex. K-1 shorter paths are selected among the detouring paths and put into the set of K paths. Then detouring paths through inward arcs to every vertex of the second shortest path are generated. If there is a shorter path than the current Kth path in the set, this path is placed in the set and the Kth path is removed from the set, and the paths in the set is rearranged in the ascending order of lengths. This procedure of generating the detouring paths and rearranging the set is repeated until the K<SUP>th</SUP>-l path of the set is obtained. The computational results for networks with about 1,000,000 nodes and 2,700,000 arcs show that this algorithm can be applied to a problem of generating the detouring paths in the metropolitan traffic networks.

유방향의 복수 최단 경로 해법에 관한 연구

장병만(Byung-Man Chang),김시곤(Si-Gon Kim) 한국SCM학회 2008 한국SCM학회지 Vol.8 No.1

BBSA 유도체의 가수분해메카니즘과 반응속도론적 연구

이석우,장병만,이광일,이기창,Suck-Woo Lee,Byung-Man Jang,Gwang Il Lee,Gi Chang Lee 대한화학회 1992 대한화학회지 Vol.36 No.6

N-Benzylidenebenzenesulfonamide 유도체의 가수분해 반응속도를 $25^{\circ}C$의 수용액에서 자외선 분광기를 사용하여 측정하고 넓은 pH 범위에 적용될 수 있는 반응속도식을 유도하였다. 가수분해 반응속도에 미치는 치환기 효과를 검토하기 위하여 Hammett plot를 한 결과 전자 끄는기에 의하여 반응속도가 촉진됨을 알 수 있었다. 가수분해 최종 생성물은 benzenesulfonamide와 benzaldehyde 이었으며 가부분해 반응속도 상수 측정과 반응속도식의 유도, 치환기 효과, general base 효과 및 최종생성물의 결과로부터 n-benzylidenebenzenesulfonamide 유도체의 가수분해 반응은 pH 0.2${\sim}$2.5에서는 hydronium ion에 의해서, pH 3.0${\sim}$8.0 사이에서는 중성의 물분자에 의하여 가수분해가 일어나고 pH 8.5 이상에서는 hydroxide ion에 의하여 진행됨을 알 수 있었다. The kinetics of the hydrolysis of N-benzylidenebenzenesulfonamide derivatives have been investigated by ultraviolet spectrophotometry in $H_2O$ at $25^{\circ}C$. A rate equation which can be applied over a wide pH range was obtained. The substituent effect on the hydrolysis of N-benzylidenebenzenesulfonamide derivatives were studied and rate of hydrolysis is known to be accelerated by electron withdrowing group. Final product of the hydrolysis was benzenesulfonamide and benzaldehyde. Base on the rate equation, substituent effect, general base effect and final products, hydrolysis of N-benzylidenebenzenesulfonamide derivatives seemed to be initiated by the hydronium ion at the pH 0.2${\sim}$2.5 and proceeded by the neutral $H_2O$ molecule at pH 3.0${\sim}$8.0 but proceeded by the hydroxide ion at above pH 8.5.

α-Phenyl-N-iso-Propylnitrone 유도체의 가수분해 반응 메카니즘과 반응 속도론적 연구

곽천근,장병만,이석우,이기창 ( Chun Geun Kwak,Byung Man Jang,Seok Woo Lee,Ki Chang Lee ) 한국유화학회 1994 한국응용과학기술학회지 Vol.11 No.1

The rate constants of hydrolysis of α-phenly-N-iso-propylnitrone and its derivatives have been determined by UV spectrophotmetry at 25℃ and a rate equation which can be applied over a wide pH range was obtained. On the basis of rate equations derived and judging from the hydrolysis products obtained and general base and substituent effect, plausible mechanism of hydrolysis in various pH range have been proposed. Below pH 4.5, the hydrolysis was initiated by the protonation and followed by the addition of water to α-carbon. Above pH 10.0, the hydrolysis was proceeded by the addition of hydroxide ion to α=carbon. In the range of 4.5~10.0, the addition of water to nitrone was rate controlling step.

Dihydro-1,4-oxathiin 유도체의 가수분해 Mechanism과 반응속도론적 연구

이광일,곽천근,장병만,김영주,한호규,남기달,이기창,Lee, Kwang Il,Kwak, Chun Geun,Jang, Byung Man,Kim, Young Ju,Hahn, Hoh Gyu,Nam, Kee Dal,Lee, Ki Chang 대한화학회 1996 대한화학회지 Vol.40 No.2

Dihydro-1, 4-oxathiin 유도체의 가수분해 반응속도를 25.deg.C의 수용액에서 자외선 분광기를 사용하여 측정하고 넓은 pH범위에서 적용될 수 있는 반응속도식을 유도하였다. 가수분해 반응속에에 미치는 치환기 효과를 검토하기 위하여 Hammett plot한 결과 전자 끄는기에 의하여 반응속도가 촉진됨을 확인할 수 있었다. 가수분해 최종 생성물은 2-(2-hydroxyethylthio)acetoacetanilide enol형이었다. 가수분해 반응속도상수 측정실험과 반응식 유도과장, 일반염기 효과, 치환기 효과 및 최종 생성물의 결과로부터 dihydro-1, 4-oxathiin 유도체의 기수분해 반응 메카니즘을 제안하였다. pH3.5이하에서는 양서자가 첨가된 dihydro-1, 4-oxathiin의 2번 탄소에 물분자의 공격에 의해 진행되며, pH3.5 이상에서는 2번 탄소에 히드록시이온의 첨가에 의하여 진행됨을 알 수 있었다. pH4.0-9.0사이에서는 dihydro-1, 4-oxathiin에 중성의 물분자가 첨가되는 것이 속도결정단계임을 알았다. The kinetics of the hydrolysis of dihydro-1, 4-oxathiin derivatives were investigated by ultraviolet spectrophotometry in H2O at $25^{\circ}C.$ A rate equation which can be applied over a wide pH range was obtained. The substituent effects on the hydrolysis of dihydro-1, 4-oxathiin derivatives were studied and the rate of hydrolysis was shown to be accelerated by electron accepting groups. Final product of the hydrolysis was 2-(2-hydroxyethylthio)acetoacet-anilide enol form. On the basis of rate equations derived and judging from hydrolysis products obtained and from general base effect and substituent effects, plausible mechanism of the hydrolysis in various pH range have been proposed. Below pH 3.5, the hydrolysis was initiated by the protonation and followed by the addition of water to 2-carbon. Above pH 10.0, the hydrolysis was proceeded by the addition of hydroxide to 2-carbon. In the range of pH 4.0∼10.0, the addition of water to dihydro-1,4-oxathiin is rate controlling step.

담지된 Pb 촉매에 의한 Ethylene Glycol 로부터 Oxalic Acid 의 합성

이광일,곽천근,장병만 ( Kwang Il Lee,Chun Geun Kwak,Byung Man Chang ) 한국공업화학회 1995 공업화학 Vol.6 No.6

Pd 금속을 활성탄에 담지 시킨 촉매를 제조하여 주 촉매로 사용하였고, 아울러 Pd와 Ni, Cu 및 Co와 같은 함금 촉매를 제조하여 ethylene glycol로부터 oxalic acid의 합성에 관하여 연구하였다. 본 연구에서 사용된 촉매는 함침법 중 흡착법과 초기 함침법으로 제조하였으며, 초기 함침법에서는 함침 과정이 끝난 촉매를 120℃에서 12시간 건조 시킨 후 430℃에서 수소 가스를 통과 시키면서 8시간 소성하여 환원 시킬 때 수율이 좋은 결과를 나타냈다. 값비싼 귀금속 촉매의 양을 줄이고 Ni, Cu 및 Co 등을 조촉매로 사용하여 활성도를 조사한 결과, Co를 사용한 촉매에서 활성이 우수하였다. 촉매의 특성을 조사하기 위하여 SEM-EDAX, X-ray diffraction 및 BET장치를 이용하였으며 촉매의 제조방법에 따라 촉매의 활성도가 다르게 나타남을 알 수 있었다. To investigate the optimum catalytic condition in the synthesis of oxalic acid from ethylene glycol, we empolyed palladium catalyst supported on activated carbon or bimetallic catalysts such as palladium-cobalt, palladium-nickel and palladium-copper supported on activated carbon. In this way, catalysts were prepared either by adsortion method or by incipient wetness method. The most effective catalyst was obtained when the catalyst was dried at 120℃ for 12hrs, followed by the reduction at 430℃ under the stream of hydrogen gas for 8hrs. In an attempt to reduce the amount of expensive noble metals to be used as a catalyst, we studied the effect of metallic promoters such as cobalt, nickel and copper as a co-catalyst. Cobalt was the only effective one when used along with palladium catalyst. In order to characterize the catalyst, we utilized scanning electron microscopy-energy dispersive X-ray spectrometer, X-ray diffraction and BET surface area. The activity of catalyst was shown to be changed depending upon how it was prepared.