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101.
Yuhao Wu Yuki Manabe Tetsuya Kanda Daniel M. German Katsuro Inoue 《Empirical Software Engineering》2017,22(3):1194-1222
Free and open source software (FOSS) plays an important role in source code reuse practice. They usually come with one or more software licenses written in the header part of source files, stating the requirements and conditions which should be followed when been reused. Removing or modifying the license statement by re-distributors will result in the inconsistency of license with its ancestor, and may potentially cause license infringement. In this paper, we describe and categorize different types of license inconsistencies and propose a method to detect them. Then we applied this method to Debian 7.5 and a collection of 10,514 Java projects on GitHub and present the license inconsistency cases found in these systems. With a manual analysis, we summarized various reasons behind these license inconsistency cases, some of which imply potential license infringement and require attention from the developers. This analysis also exposes the difficulty to discover license infringements, highlighting the usefulness of finding and maintaining source code provenance. 相似文献
102.
How the human central nervous system adjusts sensorimotor coordination to haptic stimuli is a major topic in several fields including robotics. There are studies focusing on contact positioning tasks such as catching a ball or a volley in tennis, where position control of a human hand is required only at the moment of contact for successful completion of the tasks. A previous study dealt with a task of catching a ball in a virtual environment, and reported an interesting observation of the learning process in the relationship between operational performance and energy consumption of an operator; however, the operational condition given to the operators in the previous study seemed to be relatively simple. The interest in this paper is similar to that of the previous study; however, this paper considers application of a slightly more complex operational condition to a task of catching a ball. For corresponding to increase of difficulty in operation in the task, two movements of a paddle for catching a ball are given to operators, and difference between the movements is observed. Although the final goal of the study in this paper is similar to that in the previous study, this paper considers how learning effect can be observed in operational performance by comparing the performance of novice operators with that of experienced operators. The comparison shows differences in the performances between the operators from three analytic aspects. This paper also considers how many operations are required for novice operators to exhibit the learning effect in operational performance. 相似文献
103.
Real-time traffic will be a predominant traffic type in the next generation networks, and networks with 100% reliability and
availability will be required by real-time premium traffic. It is believed that QoS guarantees could be better provided by
connection oriented networks such as Multi Protocol Label Switching (MPLS). These connection oriented networks are more vulnerable
to network failure. Conventional path protection methods perform re-routing to cope with this. However, re-routing always
causes packet losses and results in service outage. These losses are bursty in nature and highly degrade the QoS of the real-time
premium traffic. Thus, 100% availability cannot be achieved by conventional methods. The novel path protection proposed in
this paper recovers the bursty packet losses due to re-routing by using forward error correction (FEC) path. Therefore, it
can provide network architecture with no service outage for such traffic. The numerical results show that the proposed method
can achieve a very high availability for real-time premium traffic in future IP/MPLS networks.
Mitsuo Hayasaka received B.E. and M.E. degrees from the University of Electro-Communications, Tokyo, Japan in 2000 and 2002, respectively. He is currently a Ph.D. student at the University of Electro-Communications, Tokyo, Japan. His research interests involve QoS controls of real-time multimedia communications, and reliable network architecture. He is a member of IEEE, IEICE and IPSJ. Tetsuya Miki received the B.E. degree from the University of Electro-Communications, Tokyo, Japan in 1965, the M.E. and Ph.D. degrees from Tohoku University, Sendai, Japan in 1967 and 1970, respectively. He joined the Electrical Communication Laboratories of NTT in 1970, where he engaged in the research and development of high-speed digital transmission systems using coaxial cable, fiber-optical transmission systems including the initial WDM technologies, fiber-to-the-home systems, ATM systems, network management systems, and broadband network architecture. He is currently a Professor at the University of Electro-Communications, Tokyo, Japan, and is interested in photonic networks, community networks, access networks, and dependable networks. A fellow of the IEEE and IEICE, he also served as vice-president of the IEEE Communications Society in 1998 and 1999 and as vice-president of IEICE in 2003 and 2004. 相似文献
Mitsuo HayasakaEmail: |
Mitsuo Hayasaka received B.E. and M.E. degrees from the University of Electro-Communications, Tokyo, Japan in 2000 and 2002, respectively. He is currently a Ph.D. student at the University of Electro-Communications, Tokyo, Japan. His research interests involve QoS controls of real-time multimedia communications, and reliable network architecture. He is a member of IEEE, IEICE and IPSJ. Tetsuya Miki received the B.E. degree from the University of Electro-Communications, Tokyo, Japan in 1965, the M.E. and Ph.D. degrees from Tohoku University, Sendai, Japan in 1967 and 1970, respectively. He joined the Electrical Communication Laboratories of NTT in 1970, where he engaged in the research and development of high-speed digital transmission systems using coaxial cable, fiber-optical transmission systems including the initial WDM technologies, fiber-to-the-home systems, ATM systems, network management systems, and broadband network architecture. He is currently a Professor at the University of Electro-Communications, Tokyo, Japan, and is interested in photonic networks, community networks, access networks, and dependable networks. A fellow of the IEEE and IEICE, he also served as vice-president of the IEEE Communications Society in 1998 and 1999 and as vice-president of IEICE in 2003 and 2004. 相似文献
104.
Japanese/English Cross-Language Information Retrieval: Exploration of Query Translation and Transliteration 总被引:1,自引:0,他引:1
Cross-language information retrieval (CLIR), where queriesand documents are in different languages, has of late become one ofthe major topics within the information retrieval community. Thispaper proposes a Japanese/English CLIR system, where we combine aquery translation and retrieval modules. We currently target theretrieval of technical documents, and therefore the performance of oursystem is highly dependent on the quality of the translation oftechnical terms. However, the technical term translation is stillproblematic in that technical terms are often compound words, and thusnew terms are progressively created by combining existing basewords. In addition, Japanese often represents loanwords based on itsspecial phonogram. Consequently, existing dictionaries find itdifficult to achieve sufficient coverage. To counter the firstproblem, we produce a Japanese/English dictionary for base words, andtranslate compound words on a word-by-word basis. We also use aprobabilistic method to resolve translation ambiguity. For the secondproblem, we use a transliteration method, which corresponds wordsunlisted in the base word dictionary to their phonetic equivalents inthe target language. We evaluate our system using a test collectionfor CLIR, and show that both the compound word translation andtransliteration methods improve the system performance. 相似文献
105.
This letter presents a new algorithm for blind dereverberation and echo cancellation based on independent component analysis (ICA) for actual acoustic signals. We focus on frequency domain ICA (FD-ICA) because its computational cost and speed of learning convergence are sufficiently reasonable for practical applications such as hands-free speech recognition. In applying conventional FD-ICA as a preprocessing of automatic speech recognition in noisy environments, one of the most critical problems is how to cope with reverberations. To extract a clean signal from the reverberant observation, we model the separation process in the short-time Fourier transform domain and apply the multiple input/output inverse-filtering theorem (MINT) to the FD-ICA separation model. A naive implementation of this method is computationally expensive, because its time complexity is the second order of reverberation time. Therefore, the main issue in dereverberation is to reduce the high computational cost of ICA. In this letter, we reduce the computational complexity to the linear order of the reverberation time by using two techniques: (1) a separation model based on the independence of delayed observed signals with MINT and (2) spatial sphering for preprocessing. Experiments show that the computational cost grows in proportion to the linear order of the reverberation time and that our method improves the word correctness of automatic speech recognition by 10 to 20 points in a RT??= 670 ms reverberant environment. 相似文献
106.
M Kusunoki K Kimura M Nakamura Y Isaka S Yoneda H Abe 《Canadian Metallurgical Quarterly》1981,1(4):413-417
The contribution of hematocrit (Ht) changes on cerebral blood flow (CBF) and brain oxygenation in ischemic cerebrovascular disease is still controversial. In the present study, effects of Ht variations of CBF and oxygen delivery were investigated in patients with ischemic cerebrovascular disease. CBF was measured by the Xe-133 intracarotid injection method in 27 patients, whose diagnoses included completed stroke, reversible ischemic neurological deficit, and transient ischemic attack. Ht values in the patients ranged from 31 to 53%. There was a significant inverse correlation between CBF and Ht in these Ht ranges. Oxygen delivery, i.e., the product of arterial oxygen content and CBF, increased with Ht elevation and reached the maximum level in the Ht range of 40-45% and then declined. The CBF-Ht and oxygen transport-Ht relations observed in our study were similar to those in the glass-tube model studies by other workers rather than to those in intact animal experiments. From these results, it is conceivable that in ischemic cerebrovascular disease, the vasomotor adjustment was impaired in such a manner that the relations among Ht, CBF, and oxygen delivery were different from those in healthy subjects. Further, an "optimal hematocrit" for brain oxygenation was also discussed. 相似文献
107.
T. Sasaki N. Yoneyama A. Suzuki I. Ito N. Kobayashi Y. Ikemoto H. Kimura N. Hanasaki H. Tajima 《Journal of Low Temperature Physics》2006,142(3-4):377-382
The electronic phase separation on macroscopic scale is studied in the organic Mott system κ-(BEDT-TTF)2Cu[N(CN)2]Br by means of scanning microregion infrared spectroscopy using the synchrotron radiation. The phase separation appears in
the vicinity of the Mott boundary in the single crystals of which the band width is controlled by partly substituting the
BEDT-TTF molecule with the deuterated one. The transport properties under the phase separation are considered to be influenced
by the percolation process of the domains. 相似文献
108.
Ichiro Takano Yoshiharu Arai Michiko Sasaki Yoshio Sawada Kaori Yamada Takayoshi Yagasaki Yuji Kimura 《Vacuum》2006,80(7):788-792
Biodegradable plastics can be used as conventional plastics, while on disposal they decompose to water and carbon dioxide by microorganisms existing in natural environment. Products using biodegradable plastics have recently been developed in many companies pursuing ecology. In this study, surface modification of biodegradable plastics was carried out by inert ion beams for improvement of photo deterioration under an ultraviolet ray. The hardness of biodegradable plastics tended generally to decrease with irradiation of an ultraviolet ray. In this method, the hardness of ion-bombarded biodegradable plastics was kept at an initial value under an ultraviolet ray, because the modified layer by ion bombardment intercepted an ultraviolet ray. The hardness of He+ ion-bombarded biodegradable plastics showed larger value than that of Ar+ ion bombardment. He+ ion bombardment at ion energy of 10 keV produced the suitable property with both of high transmittance of a visible ray and high interception of an ultraviolet ray in a surface layer of biodegradable plastics. 相似文献
109.
In system identification, the error evolution is composed of two decoupled parts: one is the identifying information on the current estimation residual, while the other is past arithmetic errors. Previous recursive algorithms only considered how to update current prediction errors. Up to now, research has mostly been based on recursive least-squares (RLS) methods. In this note, a general recursive identification method is proposed for discrete systems. Using this new algorithm, a recursive empirical frequency-domain optimal parameter (REFOP) estimate is established. The REFOP method has the advantage of resisting disturbance noise. Some simulations are included to illustrate the new method's reliability. 相似文献
110.
Baku Katagiri Tetsuya Miyashita Takahiro Ishinabe Tatsuo Uchida 《Journal of the Society for Information Display》2003,11(3):585-590
Abstract— One problem with front‐projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front‐projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room. 相似文献