When a hard drive (HDD) is recycled, it is recommended that all files on the HDD are repeatedly overwritten with random strings for protecting their confidentiality. However, it takes a long time to overwrite them. This problem is solved by applying the -- transform (AONT) to the filesystem of the HDD. To use the HDD economically, it is desirable to use a length-preserving AONT (LP-AONT). Whereas previous AONTs cause the increase of size of a file, and no LP-AONT is secure under previous security definitions. However, it does not mean that the LP-AONT is useless;previous security definitions are too strict in practical applications. Then, by introducing the ambiguity of a message, we propose more practical security definitions of the AONT. We also show the secure implementation of the LP-AONT under the proposed security definitions. The analysis shows that our implementation is nearly optimal in terms of the success probability of an adversary. It means that the ambiguity of one message block allows us to construct the LP-AONT as secure as previous AONTs.

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When a hard drive (HDD) is recycled, it is recommended that all files on the HDD are repeatedly overwritten with random strings for protecting their confidentiality. However, it takes a long time to overwrite them. This problem is solved by applying the -- transform (AONT) to the filesystem of the HDD. To use the HDD economically, it is desirable to use a length-preserving AONT (LP-AONT). Whereas previous AONTs cause the increase of size of a file, and no LP-AONT is secure under previous security definitions. However, it does not mean that the LP-AONT is useless;previous security definitions are too strict in practical applications. Then, by introducing the ambiguity of a message, we propose more practical security definitions of the AONT. We also show the secure implementation of the LP-AONT under the proposed security definitions. The analysis shows that our implementation is nearly optimal in terms of the success probability of an adversary. It means that the ambiguity of one message block allows us to construct the LP-AONT as secure as previous AONTs.

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1. The negative potential shift, having variable durations (from 250 msec to several sec) and occurring in -- fashion by white matter stimulation, was studied with the microelectrode in the cerebellum of the rabbit anaesthetized with Nembutal. The shift ranged from several to 60 mV in magnitude. The shift was recorded from the molecular layer as well as from the layer of Purkinje cell bodies, but never observed in the white matter.
2. The shift was always preceded by the sequential spike discharge of the Purkinje cell dendrites, but did not influence the excitability of the dendrites. Furthermore, no intracellular potentials were ever recorded from the Purkinje cell dendrites and cell bodies, which could account for the long-lasting potential shif t. These results show that the shift is recorded when the microelectrode tip is positioned close to the Purkinje cell membrane, but it does not originate in the Purkinje cell. All other nerve cells in the cerebellar cortex are also excluded as candidates for possible site of origin of the shift because they are physically not in a close relationship with the Purkinje cell dendrites. Possible site of origin of the shift was discussed.
3. During the shift amplitude of the spike of the Purkinje cell dendrites increased and positive-negative spikes of its cell body were converted into monophasic-positive spikes. Possible mechanism for this phenomenon was discussed.

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Cryptography is now popularized and is widely used anywhere for many aims such as data confidentiality and integrity. The cryptographic key has a limited lifetime. For example, the National Institute of Standards and Technology published SP800-57 in order to provide cryptographic key management guidance, and it strictly limits the lifetime of the cryptographic key and the lifetime of encrypted data. That means, the data encryption key is required to be periodically updated and the associated encrypted data is required to be re-encrypted with the new key each time. The cost, especially network traffic, is crucial if the encrypted data is away from the key. In this paper we discuss what to be achieved by key updating and propose a key update mechanism reducing the communication and computation cost of re-encryption.

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This paper proposes secure regenerating codes that are composed of non-secure regenerating codes and a new

-- transform. Unlike the previous analysis of secure regenerating codes, the security of the proposed codes is analyzed in the sense of the indistinguishability. The advantage of the proposed codes is that the overhead caused by the security against eavesdropping is much less than that of previous secure regenerating codes. The security of the proposed codes against eavesdropping mainly depends on the new -- transform.

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Network coding (NC) is considered a new paradigm for distributed networks. However, NC has an

-- property. In this paper, we propose a sparse recovery approach using sparse sensing matrix to solve the NC -- problem over a finite field. The effectiveness of the proposed approach is evaluated based on a sensor network.

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The cake cutting problem is concerned with the fair allocation of a divisible good among agents whose preferences vary over it. Recently, designing strategy-proof (SP) cake cutting mechanisms has caught considerable attention from AI and MAS researchers. Previous works assumed that an agent’s utility function is additive so that theoretical analysis becomes tractable. However, in practice, agents have non-additive utility over a resource. In this paper, we consider the

-- utility function as a representative example of non-additive utility because it can widely cover agents’ preferences for such real-world resources as the usage of meeting rooms, time slots for computational resources, bandwidth usage, and so on. We first show the incompatibility between envy-freeness (EF) and Pareto efficiency (PE) when each agent has -- utility. We next propose a SP mechanism that satisfy PE, which is based on the serial dictatorship mechanism, at the sacrifice of EF. To address computational feasibility, we propose a heuristic-based allocation algorithm to find a near-optimal allocation in time polynomial in the number of agents, since the problem of finding a PE allocation is NP-hard. As another approach that abandons PE, we develop an EF and SP mechanism. Furthermore, we argue about false-name-proofness (FNP), which is the expansion of SP, and propose FNP and EF cake cutting mechanism. Finally, we evaluate our proposed mechanisms by computational experiments.

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The development of techniques for calibrating the trip distribution models from traffic volumes to obtain the O-D matrices is well advanced. Therefore, positive results on this development will be further developed by combining trip distribution and mode choice model (TDMC) and calibrating it using low cost traffic (passenger) volumes information (see Tamin 1997; Tamin and Purwanti, O 2002). As usual, the traffic (passenger) counts are expressed as a function of model form and relevant parameters. In this case , the TDMC model is represented by a function of a model formand relevant parameters. The previous research still in a burden condition of which is not realistic for some road network in urban area. So, the main objective of this research is the application of a combined trip distribution-mode choice model estimated from traffic count under equilibrium condition.

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This paper aims to analyze empirically the impact of selecting travel demand forecast techniques on estimation of user's benefit stemming from transportation investment. Three techniques are discussed in the paper: the multinominal logit (MNL), user equilibrium (UE) and -- (AON). These three techniques are compared in the empirical analysis of the urban railway project in Tokyo based on the same data set. Consequently, it is found that the user's benefit estimated by the MNL is largest, whereas the benefit by the UE is smaller than the benefit estimated by the MNL by about 10 % and the benefit estimated by the AON is smaller than the MNL by about 20%. Finally, some policy implications related to choosing the travel demand forecast techniques in transportation planning are discussed.

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Grimshaw & Mester 1988(以下G&M)は,スルは空の項構造をもつ軽動詞であり,語彙部門で動作性名詞(以下VN)と複合動詞を形成すると論じた.例えばVNがAgent, Goa1, Themeの項をもっている場合,スルは項構造全てを継承することも,部分的に継承すること(AgentとGoa1のみ継承)も可能なのである.本稿ではそのような語彙部門での複合動詞の形成は,VNに対する統語的制約(かきまぜ移動不可能)を説明できないとし,LF部門においてスルとVNが(不連続)複合動詞を形成すると論じる.複合動詞の一部となるVNはいかなる連体修飾も許さず,「の」格の項による修飾も許さない.即ちG&Mが認める部分的な項構造の継承は起こらないと主張する.これにより,G&Mの提唱する階層性をもつ項構造を想定することなく,いわゆる階層性違反(ThemeがGoalを残してVN句の外に現れる)を排除することが可能である.

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AONT (

-- Transform) is a kind of (n, n)-threshold secret sharing scheme that distributes a message m into a set of n shares such that the message m can be reconstructed if and only if n shares are collected. At CRYPTO 2000, Desai proposed a simple and faster AONT based on the CTR mode of encryption (called CTRT) and proved its security in the ideal cipher model. Though AES-128, whose key length k = 128 and block length l = 128, can be used in CTRT as a block cipher, AES-256 and AES-192 cannot be used due to its intrinsic restriction of k ≤ l. In this paper, we propose an extended CTRT (for short, XCTRT) suitable for AES-256. By thoroughly evaluating all the tricky cases, we prove that XCTRT is secure in the ideal cipher model under the same CTRT security definition. Also, we discuss the security result of XCTRT in concrete parameter settings. For more flexibility of key length, we propose a variant of XCTRT dealing with l<k ≤ 2l by slightly modifying the construction of the last block. After showing implementation details and performance evaluation of CTRT, XCTRT, and the variant, we can say that our XCTRT and its variant have high-speed encoding and decoding performance and are quite practical enough to be deployed in real-world applications.

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近年，アイデアをもつ人が不特定多数の支援者からインターネット経由で資金を募るクラウドファンディングの取り組みが盛り上がりをみせている。当初は，災害復興やスポーツ，音楽，映画，地域活性化などに関するプロジェクトが立ち上げられ，数々のプロジェクトが目標とする支援金額を集めることに成功した。ここ2，3年では，国内外で研究費獲得のためのクラウドファンディングが盛んに実施されるようになってきている。本稿では，世界の学術系クラウドファンディングの現状を整理するとともに，国内初の取り組みである「academist（アカデミスト）」の紹介を通して，学術系クラウドファンディングの可能性について考えていきたい。

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はじめに:慢性疼痛に合併するうつなどの精神症状の報告は多いが,慢性疼痛に陥りやすい性格の特徴についての報告は見受けられない.慢性疼痛と関連が深いとされる痛みの認知様式としてcatastrophizing,破局的思考が挙げられるが,強迫神経症の認知様式である脅威の"過大評価",一種の強迫行為として"反芻"があるなど破局的思考に至る要素は十分に備えている.慢性疼痛の治療では破局的思考に対する認知行動療法などが有効であると言われているが,強迫性格のある慢性疼痛患者に対して特有の有効なアプローチがないか検討してみた.結果:すべての症例で強迫性の有無にかかわらず,破局的思考,回避行動がみられたが,強迫傾向のある慢性疼痛患者の場合には,回避行動をする一方で,日常生活において,過剰な身体負荷を無意識にしていることがわかった.強迫傾向のある慢性疼痛患者では過剰な身体負荷をしていないか問診したり,身体負荷を制限する視点も必要と思われる.

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1. Potential changes in response to antidromic and mechanical stimuli were recorded across an oil-saline interface placed close to or at the non-myelinated terminal of the Pacinian corpuscle, of which the lamellae had been removed up to the central core.
2. An antidromic stimulus produced a diphasic potential indicating that an antidromic impulse can invade the terminal, while a mechanical stimulus generated a diphasic response of an -- nature superimposed on a graded response, or on the receptor potential. This -- response to mechanical stimuli can be abolished and the antidromic impulse becomes monophasic when procaine, choline or cooling is applied to the terminal.
3. When a mechanical stimulus was delivered within a few msec after an antidromic impulse, the -- response to mechanical stimuli was abolished, and only the receptor potential was observed during the refractory period of the terminal. The amplitude of the receptor potential became smaller as the interval between the mechanical and antidromic stimuli was shortened. The depression of the receptor potential could not be observed, when the terminal was made inexitable by procaine, choline and cooling so that antidromic impulses could not invade the terminal.
4: The relative amplitude of the maximum receptor potential, the all-ornothing impulse at the terminal and the mechanically and antidromatically elicited impulses at the first node of Ranvier was measured; their average ratio being 0.49: 0.36: 0.85: 1.
5. The receptor potential has a rise time of about 1 msec and the time constant of decay of its exponential falling phase is 0.9 msec, which is smaller than that obtained in intact Pacinian corpuscles.

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The optical-response extraction of Au(III) with an azo compound, bis(2,2′-dipyridyl-6-yl)diazene (BDPDA), was studied. The distribution ratio of Au was increased by the configuration change of BDPDA from trans to cis under UV irradiation (340 nm); however, the distribution ratios under UV irradiation were less than 3 times those under VIS irradiation (465 nm). For further improvement of optical-response extraction, the synergistic extraction of Au using octanoic acid as a synergist was tested. Octanoic acid was coordinated mainly with the complex of Au and cis-BDPDA, and effectively enhanced the hydrophobicity of the complex. The distribution ratio of Au under the UV irradiation increased with increasing the concentration of octanoic acid in the organic phase. In the presence of 3 mol/L octanoic acid, the distribution ratio under the UV irradiation reached up to 10 times that under the VIS irradiation.

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