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41.
Mono-elemental two-dimensional (2D) crystals (graphene, silicene, germanene, stanene, and so on), termed 2D-Xenes, have been brought to the forefront of scientific research. The stability and electronic properties of 2D-Xenes are main challenges in developing practical devices. Therefore, in this review, we focus on 2D free-standing group-IV graphene analogs (graphene quantum dots, silicane, and germanane) and the functionalization of these sheets with organic moieties, which could be handled under ambient conditions. We highlight the present results and future opportunities, functions and applications, and novel device concepts.  相似文献   
42.
Recently, the development of efficient and environmentally benign solvents has received great attention to replace current harsh organic solvents. In this context, low-transition-temperature mixtures (LTTMs) have emerged as favorable green solvents for biomass delignification. Palm oil biomass, empty fruit bunch (EFB) was pretreated with commercial l-malic acid and microwave hydrothermally extracted cactus malic acid-derived LTTMs at 60, 80, and 100 °C. The LTTMs applied in this study were derived from malic acid–choline chloride–water and malic acid–monosodium glutamate–water with a molar ratio of 2:4:2 and 3:1:5, respectively. Three first-order reactions were used to express the delignification kinetic model of EFB. The first term was based on the initial stage and assigned as infinite due to the fast rate of delignification which could not be detected. The second and third terms were proportional to bulk and residual delignification stages. A good agreement was obtained between the kinetic model and the experimental data obtained in this study with R2?≥?0.91. The activation energies for the delignification reactions using l-malic acid and cactus malic acid-based LTTMs in the bulk and residual stages were approximated as 36–56 and 19–26 kJ/mol and 34–90 and 47–87 kJ/mol, respectively.  相似文献   
43.
In this paper we introduce a roadmap algorithm for generating collision-free paths in terms of cubic B-spline curves for unmanned vehicles used in mining operations. The algorithm automatically generates collision-free paths that are curvature continuous with an upper bounded curvature and a small slope discontinuity of curvature at knots, when we are given the locations of the obstacles, the boundary geometry of the working area, positions and directions of the vehicle at the start, loading, and the goal points. Our algorithm also allows us to find a switch back point where the vehicle reverses its direction to enter the loading area. Examples are provided to demonstrate the effectiveness of the proposed algorithms.  相似文献   
44.
Danvy??s functional unparsing problem (Danvy in J. Funct. Program. 8(6), 621?C625, 1998) is to implement a type-safe ??printf?? function, which converts a sequence of heterogeneous arguments to a string according to a given format. The dual problem is to implement a type-safe ??scanf?? function, which extracts a sequence of heterogeneous arguments from a string by interpreting (Friedman and Wand in LFP, pp. 348?C355, 1984 and in Essentials of Programming Languages, MIT Press, 2008) the same format as an equally heterogeneous sequence of patterns that binds zero or more variables. We derive multiple solutions to both problems (Wand in J. ACM 27(1), 164?C180, 1980) from their formal specifications (Wand in Theor. Comput. Sci. 20(1), 3?C32, 1982). On one hand, our solutions show how the Hindley-Milner type system, unextended, permits accessing heterogeneous sequences with the static assurance of type safety. On the other hand, our solutions demonstrate the use of control operators (Felleisen et al. in Proceedings of the 1988 ACM Conference on Lisp and Functional Programming, pp. 52?C62, ACM Press, New York, 1988; Wand in POPL 85: Conference Record of the Annual ACM Symposium on Principles of Programming Languages, vol. 16, ACM Press, New York, 1985; Meyer and Wand in Logics of Programs, Lecture Notes in Computer Science, vol. 193, pp. 219?C224, Springer, Berlin, 1985) to communicate with formats as coroutines (Wand in Proceedings of the 1980 ACM Conference on Lisp and Functional Programming, vol. 12, pp. 285?C299, ACM Press, New York, 1980 and Haynes et al. in LFP, pp. 293?C298, 1984).  相似文献   
45.
46.
We propose wedge type light guide plate (LGP) adopting twin inclined cylindrical surfaces (TICS) at the incident part of a LGP. It has higher optical efficiency than conventional wedge type LGP. In dimension of LGP which the thickness of incident part is 1.5 mm and that of luminance part is 0.7 mm, the optical efficiency of wedge type LGP adopting TICS is expected to be 96% in comparison with a normal flat LGP. In addition, there is an advantage to reduce the non‐uniformity of vicinity of light emitted diodes (LEDs) by TICS reflecting light laterally. However, it is necessary that the LED centers are aligned with the intersections of TICS. The misalignment of LED causes non‐uniformity of optical profile that is slightly larger than a normal LGP.  相似文献   
47.
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   
48.
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 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   
49.
A magnetic probe array is constructed to measure precisely the spatial structure of a small fluctuating field included in a strong confinement field that varies with time. To exclude the effect of the confinement field, the magnetic probes consisting of figure-eight-wound coils are prepared. The spatial structure of the fluctuating field is obtained from a Fourier analysis of the probe signal. It is found that the probe array is more sensitive to the fluctuating field with a high mode number than that with a low mode number. An experimental demonstration of the present method is attempted using a field-reversed configuration plasma, where the fluctuating field with 0.1% of the confinement field is successfully detected.  相似文献   
50.
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   
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