著者
松原 繁夫 横尾 真 Shigeo Matsubara Makoto Yokoo
雑誌
人工知能学会誌 = Journal of Japanese Society for Artificial Intelligence (ISSN:09128085)
巻号頁・発行日
vol.15, no.5, pp.912-921, 2000-09-01

Internet and agent technologies have facilitated world-wide trade, but we sometimes encounter risky situation in exchange processes involving goods and money, i. e., fraud. This problem is becoming more serious with the growing popularity of person-to-person trade. One of the reasons for such fraud is that obtaining a new identifier in netwoeks is cheap. This makes it difficult to exclude malicious agents from trade. One solution is the imposition of an entry fee. However, if an entry fee is expensive, it discourages newcomers from starting deals. To resolve the conflict between safety and convenience, we have developed two kinds of exchange mechanisms that guarantee against defection from a contract. One reduces the entry fee by integrating multiple deals and controlling goods and money flows. We also show an extension of this mechanism that can reduce the entry fee more while taking a longer time to complete the exchange process. The other reduces the entry fee by incorporating a third party agent into the exchange process. We examine the lower bound of the entry fee for each mechanism and provide a calculation method that is able to obtain this value in linear time.
著者
広瀬 正幸 伊藤 琢巳 松原 仁 Masayuki Hirose Takumi Ito Hitoshi Matsubara
雑誌
人工知能学会誌 = Journal of Japanese Society for Artificial Intelligence (ISSN:09128085)
巻号頁・発行日
vol.13, no.3, pp.452-460, 1998-05-01

Several techniques have been developed to solve puzzle problems in conventional AI, but there are few attempts to compose problems automatically by computers. Tsume-Shogi, a mating problem of Japanese Chess, is a kind of puzzles that is created and solved according to specific rules. This paper presents a system to compose Tsume-Shogi problems by reverse method. The search space increases enormously when the reverse method is adopted, but we can reduce it by using some constraints. We conducted several experiments with our method to compose Tsume-Shogi problems and showed that our system could compose some good short Tsume-Shogi problems and some special Kyuku-Tsume problems.