Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Kyoto University|
IBARAKI Toshihide Kyoto University. Professor, 工学部, 教授 (50026192)
YVES CRAMA University of Limburg, 経済学部, 準教授
ALEXANDER V. ロシア科学院, システム研究所, 上級研究員
ART LIESTMAN Simon Fraser University, 計算科学部, 教授
SLOWOMIR PIL Simon Fraser University, 計算科学部, 教授
TIKO KAMEDA Simon Fraser University, 計算科学部, 教授
YAMASHITA Masahumi Hiroshima University. Professor, 工学部, 教授 (00135419)
KATOH Naoki Kobe University of Commerce. Professor, 管理科学部, 教授 (40145826)
OHNISHI Masamitsu Tohoku University. Associate Professor, 経済学部, 助教授 (10160566)
NAGAMOCHI Hiroshi Kyoto University. Assistant Professor, 工学部, 助手 (70202231)
FUKUSHIMA Masao Kyoto University. associate Professor, 工学部, 助教授 (30089114)
KARZANOV Alexander V. Russian Academy of Science, system Institute. Senior Researcher
LIESTMAN Art Simon Fraser University. professor
HELL Pavol Simon Fraser University. Professor
PILARSKI Slowomir Simon Fraser University. Assistant Professor
KAMEDA Tiko Simon Fraser University. Professor
CRAMA Yves University of Limburg. Associate Professor
SLOWOMIR Pil Simon Fraser大学, 情報学部, 助教授
ART Liestman Simon Fraser大学, 情報学部, 準教授
POVOL Hell Simon Fraser大学, 情報学部, 教授
TIKO Kameda Simon Fraser大学, 情報学部, 教授
|Project Period (FY)
1991 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥6,000,000 (Direct Cost : ¥6,000,000)
Fiscal Year 1992 : ¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1991 : ¥3,000,000 (Direct Cost : ¥3,000,000)
|Keywords||Distributed databases / Distributed algorithms / Coteries / Graphs and networks / Minimum cut / Concurrency control / Nonlinear optimization / 分散デ-タベ-ス / 排他制御 / コテリ- / グラフの連結性 / ブ-ル代数|
In these two years of this joint reseatch, we could invite Professor Kmeda (twice) and Professor Pilarski from Canada, and Professor karzanov from Russia, and could send Professor Ibaraki (three times), Dr. Nagamochi and Dr.Ohnishi to Canada. The following is a list of the main results of this study on "Distributed algorithms for database management, control and recovery.
1. Study of coteries as a mutual exclusion mechanism of distributes systems. First, it was pointed out that mathematical properties of coteries can be lucidly described by using the concept of Boolean functions, particularly by the concept of dual minority and self-duality. Based on this, structure of an optimal coterie in the sense of maximizing the availability was clarified for the ring and related newtworks. An efficient algorithm to compute such coteries was also proposed.
2. Study on the concurrency control of database systems. For the cautious scheduler, which had been proposed by our group, an new algorithm was proposed to improve its concurrency. Its mathematical properties were also discussed.
3. Study on the connectivity of graph and networks. When distributed systems are represented at networks, its connectivity (i.e., minimum cut) is an important measure of its capacity and reliability. We proposed a new algorithm, which is different from the existing ones in the sense of not relying on the maximum flow algorithms, and proved that it is faster than any known algorithm.
4. Study on nonlinear optimization. The problem of optimal distributed systems becomes that of nonlinear optimization if we take into account the nonlinearity of system components. For this purpose, we study nonlinear optimization algorithms, and proposed in this period a new descent algorithm for the problem of variational inequalities, which is a generalization of a nonlinear optimization problem.