著者

Yoshifumi Manabe Tatsuaki Okamoto

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.7, no.3, pp.992-999, 2012 (Released:2012-09-15)

参考文献数

18

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This paper discusses cake-cutting protocols when the cake is a heterogeneous good, represented by an interval on the real line. We propose a new desirable property, the meta-envy-freeness of cake-cutting, which has not been formally considered before. Meta-envy-free means there is no envy on role assignments, that is, no party wants to exchange his/her role in the protocol with the one of any other party. If there is an envy on role assignments, the protocol cannot be actually executed because there is no settlement on which party plays which role in the protocol. A similar definition, envy-freeness, is widely discussed. Envy-free means that no player wants to exchange his/her part of the cake with that of any other player's. Though envy-freeness was considered to be one of the most important desirable properties, envy-freeness does not prevent envy about role assignment in the protocols. We define meta-envy-freeness to formalize this kind of envy. We propose that simultaneously achieving meta-envy-free and envy-free is desirable in cake-cutting. We show that current envy-free cake-cutting protocols do not satisfy meta-envy-freeness. Formerly proposed properties such as strong envy-free, exact, and equitable do not directly consider this type of envy and these properties are very difficult to realize. This paper then shows cake-cutting protocols for two and three party cases that simultaneously achieves envy-free and meta-envy-free. Last, we show meta-envy-free pie-cutting protocols.

著者

Ippei Torii Kaoruko Ohtani Takahito Niwa Naohiro Ishii

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.7, no.3, pp.1173-1179, 2012 (Released:2012-09-15)

参考文献数

13

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This paper attempts to activate a large scale shopping district (shotengai) using new internet techniques. Recently decline of shotengai is a serious problem by development of large shopping centers. We made a new approach with internet techniques to activate shotengai, which is a typical Japanese shopping district. The Osu Shotengai is one of the most famous shotengai in Nagoya, Japan, which includes about 400 stores. We developed Osu shotengai official web site, called “At Osu.” First, the information of 400 stores in Osu shotengai, which includes 9 streets, was collected. Then we created an interactive “Information Visualization System” to put fresh information of shotengai on the web site in real time. It includes “Comment Upload System, ” where store owners can upload their comments and informing news directly on the web site. Further, we developed a new approach to stimulate store owners motivations for participating in the web site. And we also mention about an attractive and interactive web design using twitters to get opinions of users. By developing the new web site, the number of visitors of “At Osu” has increased rapidly. Many articles about this new approach to activate shotengai with a web site were published in newspapers or magazines and we have receives many inquiries.

著者

Tomoki Watanabe Satoshi Ito Kentaro Yokoi

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.5, no.2, pp.659-667, 2010 (Released:2010-06-15)

参考文献数

23

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The purpose of the work reported in this paper is to detect humans from images. This paper proposes a method for extracting feature descriptors consisting of co-occurrence histograms of oriented gradients (CoHOG). Including co-occurrence with various positional offsets, the feature descriptors can express complex shapes of objects with local and global distributions of gradient orientations. Our method is evaluated with a simple linear classifier on two well-known human detection benchmark datasets: “DaimlerChrysler pedestrian classification benchmark dataset” and “INRIA person data set”. The results show that our method reduces the miss rate by half compared with HOG, and outperforms the state-of-the-art methods on both datasets. Furthermore, as an example of a practical application, we applied our method to a surveillance video eight hours in length. The result shows that our method reduces false positives by half compared with HOG. In addition, CoHOG can be calculated 40% faster than HOG.

著者

Piyoros Tungthamthiti Kiyoaki Shirai Masnizah Mohd

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.12, pp.80-102, 2017 (Released:2017-06-15)

参考文献数

29

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Recognition of sarcasm in microblogging is important in a range of NLP applications, such as opinion mining. However, this is a challenging task, as the real meaning of a sarcastic sentence is the opposite of the literal meaning. Furthermore, microblogging messages are short and usually written in a free style that may include misspellings, grammatical errors, and complex sentence structures. This paper proposes a novel method for identifying sarcasm in tweets. It combines two supervised classifiers, a Support Vector Machine (SVM) using N-gram features and an SVM using our proposed features. Our features represent the intensity and contradictions of sentiment in a tweet, derived by sentiment analysis. The sentiment contradiction feature also considers coherence among multiple sentences in the tweet, and this is automatically identified by our proposed method using unsupervised clustering and an adaptive genetic algorithm. Furthermore, a method for identifying the concepts of unknown sentiment words is used to compensate for gaps in the sentiment lexicon. Our method also considers punctuation and the special symbols that are frequently used in Twitter messaging. Experiments using two datasets demonstrated that our proposed system outperformed baseline systems on one dataset, while producing comparable results on the other. Accuracy of 82% and 76% was achieved in sarcasm identification on the two datasets.

著者

Yu Liu Kento Emoto Kiminori Matsuzaki Zhenjiang Hu

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.9, no.1, pp.73-82, 2014 (Released:2014-03-15)

参考文献数

28

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MapReduce programming model attracts a lot of enthusiasm among both industry and academia, largely because it simplifies the implementations of many data parallel applications. In spite of the simplicity of the programming model, there are many applications that are hard to be implemented by MapReduce, due to their innate characters of computational dependency. In this paper we propose a new approach of using the programming pattern accumulate over MapReduce, to handle a large class of problems that cannot be simply divided into independent sub-computations. Using this accumulate pattern, many problems that have computational dependency can be easily expressed, and then the programs will be transformed to MapReduce programs executed on large clusters. Users without much knowledge of MapReduce can also easily write programs in a sequential manner but finally obtain efficient and scalable MapReduce programs. We describe the programming interface of our accumulate framework and explain how to transform a user-specified accumulate computation to an efficient MapReduce program. Our experiments and evaluations illustrate the usefulness and efficiency of the framework.

著者

Sayaka Akioka Yuki Ohno Midori Sugaya Tatsuo Nakajima

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.6, no.4, pp.1149-1157, 2011 (Released:2011-12-15)

参考文献数

24

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This paper proposes SPLiT (Scalable Performance Library Tool) as the methodology to improve performance of applications on multicore processors through CPU and cache optimizations on the fly. SPLiT is designed to relieve the difficulty of the performance optimization of parallel applications on multicore processors. Therefore, all programmers have to do to benefit from SPLiT is to add a few library calls to let SPLiT know which part of the application should be analyzed. This simple but compelling optimization library contributes to enrich pervasive servers on a multicore processor, which is a strong candidate for an architecture of information appliances in the near future. SPLiT analyzes and predicts application behaviors based on CPU cycle counts and cache misses. According to the analysis and predictions, SPLiT tries to allocate processes and threads sharing data onto the same physical cores in order to enhance cache efficiency. SPLiT also tries to separate cache effective codes from the codes with more cache misses for the purpose of the avoidance of cache pollutions, which result in performance degradation. Empirical experiments assuming web applications validated the efficiency of SPLiT and the performance of the web application is improved by 26%.

著者

Yuuichi Nakano Mitsuo Iwadate Hideaki Umeyama Y-h. Taguchi

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.9, no.1, pp.141-154, 2014 (Released:2014-03-15)

参考文献数

15

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Type III secretion system (T3SS) effector protein is a part of bacterial secretion systems. T3SS exists in the pathogenic and symbiotic bacteria. How the T3SS effector proteins in these two classes differ from each other should be interesting. In this paper, we successfully discriminated T3SS effector proteins between plant pathogenic, animal pathogenic and plant symbiotic bacteria based on feature vectors inferred computationally by Yahara et al. only from amino acid sequences. This suggests that these three classes of bacteria employ distinct T3SS effector proteins. We also hypothesized that the feature vector proposed by Yahara et al. represents protein structure, possibly protein folds defined in Structural Classification of Proteins (SCOP) database.

著者

Satoshi Yoshida Takashi Uemura Takuya Kida Tatsuya Asai Seishi Okamoto

出版者

Information and Media Technologies 編集運営会議

雑誌

Information and Media Technologies (ISSN:18810896)

巻号頁・発行日

vol.7, no.1, pp.129-140, 2012 (Released:2012-03-15)

参考文献数

32

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We address the problem of improving variable-length-to-fixed-length codes (VF codes). A VF code that we deal here with is an encoding scheme that parses an input text into variable length substrings and then assigns a fixed length codeword to each parsed substring. VF codes have favourable properties for fast decoding and fast compressed pattern matching, but they are worse in compression ratio than the latest compression methods. The compression ratio of a VF code depends on the parse tree used as a dictionary. To gain a better compression ratio we present several improvement methods for constructing parse trees. All of them are heuristical solutions since it is intractable to construct the optimal parse tree. We compared our methods with the previous VF codes, and showed experimentally that their compression ratios reach to the level of state-of-the-art compression methods.