http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Efficient Maximum Likelihood Approach to Channel Estimation for Space-Time Coded Systems
Tomoya AIZAWA,Teruyuki MIYAJIMA 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7
In wireless communication systems, there is a performance degradation due to fading. Orthogonal space-time block coded (OSTBC) systems are known to be useful to improve the performance in fading channels. In OSTBC systems, the knowledge of the channel is required to detect symbols. This paper proposes a channel estimation method using M-algorithm. The proposed method can drastically reduce a computational complexity of the maximum likelihood approach and provide sufficient estimate accuracy. Simulation results show the effectiveness of the proposed method.
A Structured Overlay Network Scheme Based on Multiple Different Time Intervals
( Tomoya Kawakami ) 한국정보처리학회 2020 Journal of information processing systems Vol.16 No.6
This paper describes a structured overlay network scheme based on multiple different time intervals. Many types of data (e.g., sensor data) can be requested at specific time intervals that depend on the user and the system. These queries are referred to as “interval queries.” A method for constructing an overlay network that efficiently processes interval queries based on multiple different time intervals is proposed herein. The proposed method assumes a ring topology and assigns nodes to a keyspace based on one-dimensional time information. To reduce the number of forwarded messages for queries, each node constructs shortcut links for each interval that users tend to request. This study confirmed that the proposed method reduces the number of messages needed to process interval queries. The contributions of this study include the clarification of interval queries with specific time intervals; establishment of a structured overlay network scheme based on multiple different time intervals; and experimental verification of the scheme in terms of communication load, delay, and maintenance cost.
PID Optimization Tuning and Reduction of Calculation Time based on Maximum Sensitivity
Tomoya Takagi,Yusuke Hirama,Masakatsu Harita,Hiroto Hamane,Kazuyoshi Miyazaki 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10
This paper presents one parameter tuning of PID parameters considering the trade off problem of load disturbance and robustness. And its reduction method for computer calculation is also proposed in this paper. One parameter PID tuning method has been proposed by using maximum sensitivity. PID parameters are calculated by using geometric relationship between circle Ms and L(jw). Several PID parameters are calculated considering the non-convex optimization problem of assessment function. For the performance of disturbance vs robustness, PID parameters are optimized by using integrated absolute error. However, the optimization time is long. Therefore, this paper presents a method to reduce the search range by geometric relationship. Calculation benchmark result shows that the proposed method is effective.
Pressure Effect on the Phase Transition Temperatures of Ni2Mn1−xCuxGa
Tomoya Miura,Yoshiya Adachi,Keita Endo,Ryosuke Kainuma,Takeshi Kanomata 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12
The martensitic transition temperature TM and the Curie temperature TC of the ferromagneticalloys Ni2Mn1−xCuxGa (0 ≤ x ≤ 0.40) were measured under pressure. We estimated the pressurederivatives dTM/dp and dTC/dp from the results. The values of dTM/dp and dTC/dp for Ni2MnGa(x = 0) were -4.5 K/GPa and +3.9 K/GPa, respectively. The values of dTM/dp increased fromnegative to positive with increasing x in Ni2Mn1−xCuxGa. The values of dTC/dp approached zerowith increasing x.
A Study of Towel Folding by a Robot Arm
Tomoya Oshima,Takashi Yoshimi,Makoto Mizukawa,Yoshinobu Ando 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10
In this study, we aim to construct a sequence of towel folding operations by a robot arm. In this paper, we propose the methods for spreading a towel and detecting the grasp positions. For the easy spreading of the towel, we propose how to put the towel on the table. The proposed method lifts one vertex of the towel, and detects the shadow part by using a camera image for recognizing the overlapped condition of the towel. For the folding motion of the towel, we set the vertices of the towel edges as grasping positions. So, we propose the way to detect the vertices of the towel correctly by generating a rectangle which includes all feature points of the towel by using image processing.
( Tomoya Iida ),( Suguru Nakagaki ),( Shuji Satoh ),( Haruo Shimizu ),( Hiroyuki Kaneto ),( Hiroshi Nakase ) 대한장연구학회 2017 Intestinal Research Vol.15 No.2
Background/Aims: Although multiple treatment options exist for the management of sigmoid colon volvulus, no study has examined the factors associated with successful endoscopic detorsion. This study aimed to examine the clinical course of patients with sigmoid colon volvulus and to identify factors related to successful endoscopic detorsion. Methods: This study included 30 cases (21 patients) of sigmoid volvulus from among 545 cases of intestinal obstruction at a single center. We retrospectively examined the clinical course and the factors associated with the possibility of endoscopic detorsion of sigmoid colon volvulus. Results: The rate of laxative use among the study participants was 76.2%; the rate of comorbid neuropsychiatric disorders was 61.9%; and 57.1% of patients had a history of open abdominal surgery. All patients were initially treated with endoscopic detorsion, and this procedure had a 61.9% success rate. The recurrence rate after detorsion was as high as 46.2%, but detorsion during revision endoscopy was possible in all cases. Statistical analysis revealed that the absence of abdominal tenderness (P =0.027), the use of laxatives (P =0.027), and a history of open abdominal surgery (P =0.032) were factors predictive of successful endoscopic detorsion. Conclusions: The results of our study are consistent with previous reports with respect to the success rate of endoscopic detorsion, the subsequent recurrence rate, and the proportion of patients requiring surgical treatment. In addition, we identified the absence of abdominal tenderness, the use of laxatives, and history of open abdominal surgery as factors predicting successful endoscopic detorsion of sigmoid colon volvulus. (Intest Res 2017;15:215-220)
Estimation of Rotation and Divergence from Optical Flow Constraint
Tomoya Kawakami,Teruo Yamaguchi,Hiroshi Harada 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10
In previous paper[1], we suggested a new algorithm to estimate optical flow and motion parameters (angular velocity and scale of enlargement). There are two advantages in this method. First, more accurate optical flow and motion parameters can be estimated because it is strictly consistent with the assumption that the motion contains not only translation but also rotation and divergence. Second, this method can reduce the cost of calculation because optical flow and motion parameters can be estimated at the same time after scanning images only once. We examined the effectiveness of the proposed method in some simulations in previous paper. In this paper, we will show experimental results of proposed method for more realistic scenes.
Tomoya Oyamada,Katsushi Yokoyama,Michiko Morinaga,Masashi Suzuki,Kozo Makino,Kozo Makino 한국미생물학회 2007 The journal of microbiology Vol.45 No.3
The DcuS-R two-component system of Escherichia coli senses C4-dicarboxylates of the medium and regulates expression of the genes related to utilization of them. It is known that phospho-DcuR induces expression of genes such as the dcuB-fumB operon, the frdABCD operon, and the dctA gene. We analyzed promoters of the dcuS-R operon to elucidate the transcriptional regulation system. We found a novel internal promoter within the dcuS gene that is regulated by the transcriptional regulator, CRP-cAMP, in both aerobic and anaerobic conditions.