This paper describes a high-speed MT connector assembly method. This technique uses adhesive with a short hardening time, is highly reliable and does not require a polishing process, thus reducing the connector assembly time. First, we investigated an alpha-cyanoacrylate adhesive that hardens quickly and whose adhesive strength does not decrease under high humidity and high temperature conditions, thus ensuring its excellent reliability for outside use. In addition, we investigated variations in the position of the fiber endface on the ferrule endface with a view to obtaining a low insertion loss. Based on the results, we assembled an MT connector using our proposed high-speed assembly method. We confirmed that the assembly time could be reduced to less than 70% of the time required with the conventional method. MT connectors assembled using this technique have a low insertion loss and stable environmental characteristics.

Let G = (V,E) be an edge weighted graph with n vertices and m edges. For a given integer p with 1 < p < n, we call a set X V of p vertices a p-maximizer if X has a property that the edge-connectivity of the graph obtained by contracting X into a single vertex is no less than that of the graph obtained by contracting any other subset of p vertices. In this paper, we first show that there always exists an ordering v1,v2,...,vn of vertices in V such that, for each i = 2,3,...,n - 1, set {v1,v2,...,vi} is an i-maximizer. We give an O(mn + n2log n) time algorithm for finding such an ordering and then show an application to the source location problem.

iPat/OMP is an interactive parallelization assistance tool for OpenMP. In the present paper, we describe the design concept of iPat/OMP, the parallelization sequence achieved by the tool and its current implementation status. In addition, we present an evaluation of the performance of the implemented functionalities. The experimental results show that iPat/OMP can detect parallelism and create an appropriate OpenMP directive for several for-loops.

FPGAs (Field-Programmable Gate Arrays) have been widely used as coprocessors to boost the performance of data-intensive applications [1],[2]. However, there are several challenges to further boost FPGA performance: the communication overhead between the host workstation and the FPGAs can be substantial; large-scale applications cannot fit in a single FPGA because of its limited capacity; mapping an application algorithm to FPGAs still remains a daunting job in configurable system design. To circumvent these problems, we propose in this paper the FPGA-based Hierarchical-SIMD (H-SIMD) machine with its codesign of the Pyramidal Instruction Set Architecture (PISA). PISA comprises high-level instructions implemented as FPGA functions of coarse-grain SIMD (Single-Instruction, Multiple-Data) tasks to facilitate ease of program development, code portability across different H-SIMD implementations and high performance. We assume a multi-FPGA board where each FPGA is configured as a separate SIMD machine. Multiple FPGA chips can work in unison at a higher SIMD level, if needed, controlled by the host. Additionally, by using a memory switching scheme and the high-level PISA to partition applications into coarse-grain tasks, host-FPGA communication overheads can be hidden. We enlist the two-dimensional Fast Fourier Transform (2D FFT) to test the effectiveness of H-SIMD. The test results show sustained high performance for this problem. The H-SIMD machine even outperforms a Xeon processor for this problem.

An FRPA (frequency reuse power allocation) technique by employing the frequency reuse notion as a strategy for overcoming the ICI (intercell interference) and maintaining the QoS (quality of service) at the cell boundary is described for broadband cellular networks. In the scheme, the total bandwidth is divided into sub-bands and two different power levels are then allocated to sub-bands based on the frequency reuse for forward-link cell planning. In order to prove the effectiveness of the proposed algorithm, a Monte Carlo simulation was performed based on the Chernoff upper bound. The simulation shows that this technique can achieve a high channel throughput while maintaining the required QoS at the cell boundary.

This paper introduces a network-aware video delivery framework where the quality-of-service (QoS) interaction between prioritized packet video and relative differentiated service (DiffServ) network is taken into account. With this framework, we propose a dynamic class mapping (DCM) scheme to allow video applications to cope with service degradation and class-based resource constraint in a time-varying network environment. In the proposed scheme, an explicit congestion notification (ECN)-based feedback mechanism is utilized to notify the status of network classes and the received service quality assessment to the end-host applications urgently. Based on the feedback information, DCM agent at ingress point can dynamically re-map each packet onto a network class in order to satisfy the desired QoS requirement. Simulation results verify the enhanced QoS performance of the streaming video application by comparing the static class-mapping and the class re-mapping based on loss-driven feedback.

This paper presents CPPC (Controller/Precompiler for Portable Checkpointing), a checkpointing tool designed for heterogeneous clusters and Grid infrastructures through the use of portable protocols, portable checkpoint files and portable code. It works at variable level being user-directed, thus generating small checkpoint files. It allows parallel processes to checkpoint independently, without runtime coordination or message-logging. Consistency is achieved at restart time by negotiating the restart point. A directive-based checkpointing precompiler has also been implemented to ease up user's effort. CPPC was designed to work with parallel MPI programs, though it can be used with sequential ones, and easily extended to parallel programs written using different message-passing libraries, due to its highly modular design. Experimental results are shown using CPPC with different test applications.

Multi-projector technology has been under consideration in recent years. This technology allows the generation of wide field of view and high-resolution images in a cost-effective manner. It is expected to be applied extensively to training simulators where vivid immersive sensations and precision are required. However, in many systems the viewing frustums cannot be automatically assigned for distributed rendering, and the required manual setup is complicated and difficult. This is because the camera should be coincide exactly with a desired eye point to avoid perspective distortions. For the actual applications, the camera is seldom able to be set up at the desired eye point because of physical constraints, e.g., a narrow cockpit with many instruments. To resolve this issue, we have developed a "virtual camera method" that yields high-precision calibration regardless of the camera position. This method takes advantage of the quadratic nature of the display surface. We developed a practical real-time multi-projector display system for applications such as training simulators, that require high-accuracy in geometry and rapid response time.

This paper presents a way of using a linear regression model to produce a single-valued criterion that indicates the perceived importance of each block in a stream of speech blocks. This method is superior to the conventional approach, voice activity detection (VAD), in that it provides a dynamically changing priority value for speech segments with finer granularity. The approach can be used in conjunction with scalable speech coding techniques in the context of IP QoS services to achieve a flexible form of quality control for speech transmission. A simple linear regression model is used to estimate a mean opinion score (MOS) of the various cases of missing speech segments. The estimated MOS is a continuous value that can be mapped to priority levels with arbitrary granularity. Through subjective evaluation, we show the validity of the calculated priority values.

In RSA public-key cryptosystem, a small private key is often preferred for efficiency but such a small key could degrade security. Thus the Chinese Remainder Theorem (CRT) is tactically used, especially in time-critical applications like smart cards. As for using the CRT in RSA, care must be taken to resist partial key exposure attacks. While it is common to choose two distinct primes with similar size in RSA, May has shown that a composite modulus N can be factored in the balanced RSA with the CRT of half of the least (or most) significant bits of a private key is revealed with a small public key. However, in the case that efficiency is more critical than security, such as smart cards, unbalanced primes might be chosen. Thus, we are interested in partial key exposure attacks to the unbalanced RSA with the CRT. In this paper, we obtain the similar results as the balanced RSA. We show that in the unbalanced RSA if the N1/4 least (or most) significant bits are revealed, a private key can be recovered in polynomial time under a small public key.

Real-time applications are indispensable for conducting research and business in government, industry, and academic organizations. Recently, real-time applications with security requirements increasingly emerged in large-scale distributed systems such as Grids. However, the complexities and specialties of diverse security mechanisms dissuade users from employing existing security services for their applications. To effectively tackle this problem, in this paper we propose a security middleware (SMW) model from which security-sensitive real-time applications are enabled to exploit a variety of security services to enhance the trustworthy executions of the applications. A quality of security control manager (QSCM), a centerpiece of the SMW model, has been designed and implemented to achieve a flexible trade-off between overheads caused by security services and system performance, especially under situations where available resources are dynamically changing and insufficient. A security-aware scheduling mechanism, which plays an important role in QSCM, is capable of maximizing quality of security for real-time applications running in distributed systems as large-scale as Grids. Our empirical studies based on real world traces from a supercomputing center demonstratively show that the proposed model can significantly improve the performance of Grids in terms of both security and schedulability.

An algorithm is described for solving the node-to-set disjoint paths problem in bi-rotator graphs, which are obtained by making each edge of a rotator graph bi-directional. The algorithm is of polynomial order of n for an n-bi-rotator graph. It is based on recursion and divided into three cases according to the distribution of destination nodes in the classes into which the nodes in a bi-rotator graph are categorized. We estimated that it obtains 2n-3 disjoint paths with a time complexity of O(n5), that the sum of the path lengths is O(n3), and that the length of the maximum path is O(n2). Computer experiment showed that the average execution time was O(n3.9) and, the average sum of the path lengths was O(n3.0).

In [5], the following pyramid construction problem was proposed: Given nonnegative valued functions ρ and µ in d variables, we consider the optimal pyramid maximizing the total parametric gain of ρ against µ. The pyramid can be considered as the optimal unimodal approximation of ρ relative to µ, and can be applied to hierarchical data segmentation. In this paper, we give efficient algorithms for a couple of two-dimensional pyramid construction problems.

In many parallel programs, run-time array redistribution is usually required to enhance data locality and reduce remote memory access on the distributed memory multicomputers. In general, array distribution can be classified into regular distribution and irregular distribution according to the distribution fashion. Many methods for performing regular array redistribution have been presented in the literature. However, for the heterogeneous computation environment, irregular array redistributions can be used to adjust data assignment at run-time. In this paper, an Essential Cycle Calculation method for unequal block sizes array redistribution is presented. In the ECC method, a processor first computes the source/destination processor/data sets of array elements in the first essential cycle of the local array it owns. From the source/destination processor/data sets of array elements in the first essential cycle, we can construct packing/unpacking pattern tables. Since each essential cycle has the same communication pattern, based on the packing/unpacking pattern tables, a processor can pack/unpack array elements efficiently. To evaluate the performance of the ECC method, we have implemented this method on an IBM SP2 parallel machine and compare it with the Sequence method. The cost models for these methods are also presented. The experimental results show that the ECC method greatly outperforms the Sequence method for all test samples.

In everyday life, a situation often occurs wherein two or more persons with different personal schedules must determine a single job schedule. The authors focus on the practical concept of rent and loan and propose a scheduling system. This system generates a schedule that automatically coordinates with a state involving minimum rent and loan. They also propose a method that employs the analytic network process (ANP) for setting individual priorities based on the rent and loan information. Furthermore, the authors implement the proposed system as a simulation system and verify whether it generates a fair schedule by computing the sum of the rent and loan of different individuals. The result shows that in comparison with human scheduling, the proposed method generates a fairer schedule by computing the rent and loan of each individual.

Differentiated-services model has been prevailed as a scalable solution to provide quality of service over the Internet. Many researches have been focused on per hop behavior or a single domain behavior to enhance quality of service. Thus, there are still difficulties in providing the end-to-end guaranteed service when the path between sender and receiver includes multiple domains. Furthermore differentiated-services model mainly considers quality of service for traffic aggregates due to the scalability, and the quality of service state may be time varying according to the network conditions in the case of relative service model, which make the problem more challenging to guarantee the end-to-end quality-of-service. In this paper, we study class mapping mechanisms along the path to provide the end-to-end guaranteed quality of service with the minimum networking price over multiple differentiated-services domains. The proposed mechanism includes an effective implementation of relative differentiated-services model, quality of service advertising mechanism and class selecting mechanisms. Finally, the experimental results are provided to show the performance of the proposed algorithm.

This paper investigates zero pronouns in Korean, especially focusing on the center transitions of adjacent utterances under the framework of Centering Theory. Four types of nominal entity (Epair, Einter, Eintra, and Enon) from Centering Theory are defined with the concept of inter-, intra-, and pairwise salience. For each entity type, a case study of zero phenomena is performed through analyzing corpus and building a pronominalization model. This study shows that the zero phenomena of entities which have been neglected in previous Centering works are explained via the center transition of the second previous utterance, and provides valuable results for pronominalization of such entities, such as p2-trans rule. We improve the accuracy of pronominalization model by optimal feature selection and show that our accuracy outperforms the accuracy of previous works.

This study is devoted to a half-wave dipole with a conductor plane at a distance much smaller than a quarter wavelength which we designate as an ultra low profile dipole (ULPD) antenna in this paper. The concerns of ULPD antenna are the feeding method and the impedance matching, because the input impedance usually tends to be lowered by the existence of a metallic structure in its proximity. In this paper, we propose a ULPD antenna with an excellent impedance matching and a coaxial feed built within the antenna structure so that the external matching and a balun are not required. A coaxial cable is used as a feed line and extended to be a half of a half wavelength dipole. The other half is made up of a parasitic element, which is connected to the outer conductor of the coaxial radiator. To make a matching, the outer conductor of the coaxial radiator is stripped off at a suitable length, and the total length of a dipole is considered for its resonance at a desired frequency of 2 GHz. The experiment has been conducted. The results show the return loss of -27 dB and the maximum gain of 9 dBi in the normal direction to the conductor plane. The computational results are also obtained, which agree well with the experimental results.

Cross-document personal name resolution is the process of identifying whether or not a common personal name mentioned in different documents refers to the same individual. Most previous approaches usually rely on lexical matching such as the occurrence of common words surrounding the entity name to measure the similarity between documents, and then clusters the documents according to their referents. In spite of certain successes, measuring similarity based on lexical comparison sometimes ignores important linguistic phenomena at the semantic level such as synonym or paraphrase. This paper presents a semantics-based approach to the resolution of personal name crossover documents that can make the most of both lexical evidences and semantic clues. In our method, the similarity values between documents are determined by estimating the semantic relatedness between words. Further, the semantic labels attached to sentences allow us to highlight the common personal facts that are potentially available among documents. An evaluation on three web datasets demonstrates that our method achieves the better performance than the previous work.

The 5-cm-diameter double-sided YBa2Cu3O7 (YBCO) films were prepared by metal organic deposition (MOD) using a commercially available metal-naphthenate coating solution. Firstly, YBCO film was prepared by MOD on one side of a double-side-polished 5-cm-diameter LaAlO3 substrate. Secondly, another side was similarly coated with YBCO by MOD. After the latter processing, degradation of average Jc value in the first side was not observed; but the fluctuation of critical current density Jc slightly increased. The double-sided YBCO films showed average Jc values of 0.8-1.0 MA/cm2 at 77 K and microwave surface resistances Rs(12 GHz) of 0.86-1.07 mΩ at 70 K.