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71.
Recently, the size of solder bump interconnects have been significantly reduced with the advent of high-density packaging,
and thus the evaluation of electromigration in solder bumps has become necessary. The present paper proposes a simple method
to test the electromigration resistance of Pb-free solders. One of the key points of the present method is the fabrication
of a simple solder sample that can produce sufficient current density to cause electromigration. Moreover, the actual local
temperature of a small area subjected to electromigration in the sample was measured by a direct method. A right-angled diamond-shaped
hole was introduced in a thin film of solder using a focused-ion-beam system. A direct current was supplied to the film far
from the hole, perpendicular to the diagonal of the hole. In this way, the current density was concentrated near to the corner
of the hole, and the value of this was obtained through a theoretical analysis. It was noted that the steady temperature in
the film along a line extending from the diagonal, remained constant, although the current density decreased gradually far
from the corner. Therefore, the temperature at a position near the corner, where electromigration takes place, can easily
be found by measuring the temperature far from the corner. The temperature was measured directly under current flow conditions
by utilizing the chemical reagents with known melting points. Finally, by measuring the ratio of hillock volume to the time
for the current supply as a measure of the atomic flux divergence due to electromigration, the corresponding resistances of
some Pb-free solders to electromigration were evaluated. 相似文献
72.
Vasileios Belagiannis Xinchao Wang Horesh Beny Ben Shitrit Kiyoshi Hashimoto Ralf Stauder Yoshimitsu Aoki Michael Kranzfelder Armin Schneider Pascal Fua Slobodan Ilic Hubertus Feussner Nassir Navab 《Machine Vision and Applications》2016,27(7):1035-1046
Multiple human pose estimation is an important yet challenging problem. In an operating room (OR) environment, the 3D body poses of surgeons and medical staff can provide important clues for surgical workflow analysis. For that purpose, we propose an algorithm for localizing and recovering body poses of multiple human in an OR environment under a multi-camera setup. Our model builds on 3D Pictorial Structures and 2D body part localization across all camera views, using convolutional neural networks (ConvNets). To evaluate our algorithm, we introduce a dataset captured in a real OR environment. Our dataset is unique, challenging and publicly available with annotated ground truths. Our proposed algorithm yields to promising pose estimation results on this dataset. 相似文献
73.
Audio-visual speech recognition (AVSR) has shown impressive improvements over audio-only speech recognition in the presence of acoustic noise. However, the problems of region-of-interest detection and feature extraction may influence the recognition performance due to the visual speech information obtained typically from planar video data. In this paper, we deviate from the traditional visual speech information and propose an AVSR system integrating 3D lip information. The Microsoft Kinect multi-sensory device was adopted for data collection. The different feature extraction and selection algorithms were applied to planar images and 3D lip information, so as to fuse the planar images and 3D lip feature into the visual-3D lip joint feature. For automatic speech recognition (ASR), the fusion methods were investigated and the audio-visual speech information was integrated into a state-synchronous two stream Hidden Markov Model. The experimental results demonstrated that our AVSR system integrating 3D lip information improved the recognition performance of traditional ASR and AVSR system in acoustic noise environments. 相似文献
74.
Takuma Torii Tomio Kamada Kiyoshi Izumi Kenta Yamada 《Artificial Life and Robotics》2017,22(3):301-307
Artificial market simulations have the potential to be a strong tool for studying rapid and large market fluctuations and designing financial regulations. High-frequency traders, that exchange multiple assets simultaneously within a millisecond, are said to be a cause of rapid and large market fluctuations. For such a large-scale problem, this paper proposes a software or computing platform for large-scale and high-frequency artificial market simulations (Plham: /pl\(\Lambda\)m). The computing platform, Plham, enables modeling financial markets composed of various brands of assets and a large number of agents trading on a short timescale. The design feature of Plham is the separation of artificial market models (simulation models) from their execution (execution models). This allows users to define their simulation models without parallel computing expertise and to choose one of the execution models they need. This computing platform provides a prototype execution model for parallel simulations, which exploits the variety in trading frequency among traders, that is, the fact that some traders do not require up-to-date information of markets changing in millisecond order. We evaluated a prototype implementation on the K computer using up to 256 computing nodes. 相似文献
75.
Noriaki Kamiyama Ryoichi KawaharaTatsuya Mori Shigeaki HaradaHaruhisa Hasegawa 《Computer Communications》2011,34(7):883-897
Traffic caused by P2P services dominates a large part of traffic on the Internet and imposes significant loads on the Internet, so reducing P2P traffic within networks is an important issue for ISPs. In particular, a huge amount of traffic is transferred within backbone networks; therefore reducing P2P traffic is important for transit ISPs to improve the efficiency of network resource usage and reduce network capital cost. To reduce P2P traffic, it is effective for ISPs to implement cache devices at some router ports and reduce the hop length of P2P flows by delivering the required content from caches. However, the design problem of cache locations and capacities has not been well investigated, although the effect of caches strongly depends on the cache locations and capacities. We propose an optimum design method of cache capacity and location for minimizing the total amount of P2P traffic based on dynamic programming, assuming that transit ISPs provide caches at transit links to access ISP networks. We apply the proposed design method to 31 actual ISP backbone networks and investigate the main factors determining cache efficiency. We also analyze the property of network structure in which deploying caches are effective in reducing P2P traffic for transit ISPs. We show that transit ISPs can reduce the P2P traffic within their networks by about 50-85% by optimally designing caches at the transit links to the lower networks. 相似文献
76.
There is huge diversity among navigation and path-planning problems in the real world because of the enormous number and great
variety of assumptions about the environments, constraints, and tasks imposed on a robot. To deal with this diversity, we
propose a new solution to the path-planning and navigation of a mobile robot. In our approach, we formulated the following
two problems at each time-step as discrete optimization problems: (1) estimation of a robot's location, and (2) action decision.
For the first problem, we minimize an objective function that includes a data term, a constraint term, and a prediction term.
This approach is an approximation of Markov localization. For the second problem, we define and minimize another objective
function that includes a goal term, a smoothness term, and a collision term. Simulation results show the effectiveness of
our approach.
This work was presented in part at the Fifth International Symposium on Artificial Life and Robotics, Oita, Japan, January
26–28, 2000 相似文献
77.
To achieve smooth real-world interaction between people and computers, we developed a system that displays a three-dimensional
computer-graphic human-like image from the waist up (anthropomorphic software robot: hereinafter “robot”) on the display,
that interactively sees and hears, and that has fine and detailed control functions such as facial expressions, line of sight,
and pointing at targets with its finger. The robot visually searches and identifies persons and objects in real space that
it has learned in advance (registered space, which was our office in this case), manages the history information of the places
and times it found objects and/or persons, and tells the user, indicating their three-dimensional positions with line of sight
and its finger. It interactively learns new objects and persons with line of with their names and owners. By using this function,
the robot can engage in simple dialogue (do a task) with the user.
Osamu Hasegawa, Ph.D.: He received the B.E. and M.E. degrees from the Science University of Tokyo, in 1988, 1990 respectively. He received Ph.D.
degree from the University of Tokyo, in 1993. Currently, he is a senior research scientist at the Electrotechnical Laboratory
(ETL), Tsukuba, Japan. His research interests include Computer Vision and Multi-modal Human Interface. Dr. Hasegawa is a member
of the AAAI, the Institute of Electronics, Information and Communication Engineers, Japan (IEICE), Information Processing
Society of Japan and others.
Katsuhiko Sakaue, Ph.D.: He received the B.E., M.E., and Ph.D. degrees all in electronic engineering from the University of Tokyo, in 1976, 1978
and 1981, respectively. In 1981, he joined the Electrotechnical Laboratory, Ministry of International Trade and Industry,
and engaged in researches in image processing and computer vision. He received the Encouragement Prize in 1979 from IEICE,
and the Paper Award in 1985 from Information Processing Society of Japan. He is a member of IEICE, IEEE, IPSJ, ITE.
Satoru Hayamizu, Ph.D.: He is a leader of Interactive Intermodal Integration Lab. at Electrotechnical Laboratory. He received the B.E., M.E., Ph.D.
degrees from Tokyo University. Since 1981, he has been working on speech recognition, spoken dialogue, and communication with
artifacts. From 1989 to 1990, he was a visiting scholar in Carnegie Mellon University and in 1994 a visiting scientist in
LIMSI/CNRS. 相似文献
78.
Minimizing False Positives of a Decision Tree Classifier for Intrusion Detection on the Internet 总被引:1,自引:0,他引:1
Satoru Ohta Ryosuke Kurebayashi Kiyoshi Kobayashi 《Journal of Network and Systems Management》2008,16(4):399-419
Machine learning or data mining technologies are often used in network intrusion detection systems. An intrusion detection
system based on machine learning utilizes a classifier to infer the current state from the observed traffic attributes. The
problem with learning-based intrusion detection is that it leads to false positives and so incurs unnecessary additional operation
costs. This paper investigates a method to decrease the false positives generated by an intrusion detection system that employs
a decision tree as its classifier. The paper first points out that the information-gain criterion used in previous studies
to select the attributes in the tree-constructing algorithm is not effective in achieving low false positive rates. Instead
of the information-gain criterion, this paper proposes a new function that evaluates the goodness of an attribute by considering
the significance of error types. The proposed function can successfully choose an attribute that suppresses false positives
from the given attribute set and the effectiveness of using it is confirmed experimentally. This paper also examines the more
trivial leaf rewriting approach to benchmark the proposed method. The comparison shows that the proposed attribute evaluation
function yields better solutions than the leaf rewriting approach.
相似文献
Satoru OhtaEmail: |
79.
Yoshimasa A. Ono Jun'ichiro Hara Katsuhiko Nagai Kiyoshi Kawamura 《Journal of Low Temperature Physics》1977,27(3-4):513-536
The shear viscosity (T) in the Balian-Werthamer (BW) state of superfluid
3
He is calculated variationally throughout the region 0t 1(t=T/T
c) from the transport equation for Bogoliubov quasiparticles. Coherence factors are treated exactly in the calculation of the collision integral. The numerical result for
=s= s(T)/n(Tc) agree very well with experiment in the range 0.8t1.0. Analytic expressions
= 0.577 (1–1.0008t) and
=1–(23/64) [=(T)/k
B
T] are obtained in the low-temperature region and in the vicinity ofT
c, respectively. From the numerical analysis it is shown that the latter equation is valid only in the temperature range 0.9997t1.0.Supported by the Research Institute for Fundamental Physics, Kyoto University. 相似文献
80.
Summary
Copolymerization of vinyl chloride (VC) and ethylene with Cp*Ti( OCH3)3/MAO catalyst was investigated. The Cp*Ti( OCH3)3/MAO catalyst initiated the copolymerization of VC with ethylene, although the copolymer yields were low. In the 13C NMR spectra of the copolymers, the peaks based on junction part between VC and ethylene was observed, but the signals were
small. From DSC measurement of the copolymers, only one glass transition temperature was observed. Thus, it is clear that
the copolymerization with Cp*Ti( OCH3)3/MAO catalysts gave the copolymer, and the copolymer consisting of block sequence rather than random copolymer.
Received: 13 November 2002/Revised: 6 January 2003/Accepted: 10 January 2003
Correspondence to Kiyoshi Endo 相似文献