Shaping-Power-Constrained Transceiver Designs for MIMO AF Relaying Systems With Direct Link

Han-Bae Kong,Changick Song,Haewook Park,Inkyu Lee IEEE 2015 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.14 No.1

<P>In this paper, we propose new relay transceiver designs based on the minimum mean square error (MMSE) criterion for amplify-and-forward multiple-input-multiple-output (MIMO) relaying systems with direct link. Since each antenna element is equipped with its own power amplifier, a norm power constraint, which restricts the transmit power with the expected norm of the transmit signal vector, is not suitable for practical systems. Therefore, we consider a shaping constraint (SC), which imposes a limit on the shape of the transmit covariance matrix. The SC includes several power constraints such as the peak power constraint and the per-antenna power constraint as special cases. To this end, we first derive the optimal structure of the MMSE relay transceiver under the SC. Then, by introducing an upper bound of the mean square error, we provide closed-form relay transceiver solutions. Due to limited bandwidth of the feedback channel, perfect channel knowledge at the transmitter may not be feasible. Thus, we also propose a quantized relay transceiver design based on Grassmannian codebooks for a limited-feedback scenario. From simulation results, it is confirmed that the proposed relay transceiver techniques demonstrate a significant performance improvement compared with conventional schemes.</P>

Diversity of Coded Beamforming in MIMO-OFDM AF Relaying Systems With Direct Link

Kong, Han-Bae,Song, Changick,Ahn, Minki,Lee, Inkyu IEEE 2015 IEEE Transactions on Vehicular Technology VT Vol.64 No.8

<P>This paper investigates the diversity order of beamforming schemes in frequency-selective multiple-input multiple-output (MIMO) amplify-and-forward (AF) relaying channels with a nonnegligible direct link between the source and the destination. In this system, orthogonal frequency-division multiplexing and bit-interleaved coded modulation schemes are adopted to exploit multipath diversity. Due to a nonconvex property of the problem, the optimal performance of flat-fading MIMO relaying channels, which is imperative to derive the diversity order, is still unknown. To this end, we first identify upper and lower bounds of the signal-to-noise ratio (SNR) of the flat-fading channels, which lead to upper and lower bounds of diversity order of coded beamforming in frequency-selective channels. Then, we establish the diversity order as a closed form by showing that these bounds are tight. In addition, our analysis provides an insightful guideline for code constructions to achieve a proper diversity gain of the system. The accuracy of our analysis is validated through simulation results.</P>

Joint MMSE Transceiver Designs for MIMO AF Relaying Systems With Direct Link

Han-Bae Kong,Hun Min Shin,Taeseok Oh,Inkyu Lee INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS 2017 IEEE Transactions on Wireless Communications Vol. No.

<P>In this paper, we provide minimum mean-squared error-based source-relay-destination transceiver designs for multiple-input multiple-output amplify-and-forward relaying systems, where direct link between the source and the destination is non-negligible. In an earlier work, a local optimal technique was introduced which employs a projected gradient method and an interior point method. Since these methods may have quite high computational complexity, we investigate a new local optimal solution for the source-relay-destination transceiver which has low complexity. To this end, we first introduce the optimal closed-form solution for the relay transceiver for given source and destination filters. Then, for given relay and destination transceivers, the optimal source precoder design is derived, which requires only 1-D bisection search. Based on these solutions, we propose a joint optimization algorithm which iteratively finds a local optimal solution. Also, we introduce a simple non-iterative algorithm which computes filters in closed-forms with low complexity. Furthermore, since perfect channel knowledge may not be feasible in practical systems, a joint transceiver technique which is robust to channel uncertainties is provided. It is confirmed by simulation results that the proposed schemes outperform conventional techniques with significantly reduced complexity.</P>

Wireless Peer Discovery in Heterogeneous Half-/Full-Duplex Networks

Kong, Han-Bae,Kang, Seowoo,Lee, Inkyu IEEE 2017 IEEE communications letters Vol.21 No.4

<P>In this letter, we investigate wireless peer discovery, which finds neighbor nodes to establish connections among peers. Unlike half-duplex (HD) nodes, which operate in either one of transmitting and receiving modes, full-duplex (FD) nodes can transmit and receive signals simultaneously, and thus the average number of discovered peers (ADP) can be enhanced by employing the FD nodes. First, we analyze the ADP modeling the spatial distribution of nodes as Poisson point processes, and then provide interesting observations on the ADP. The ADP is relevant to the transmission probability (TP), which means the probability that an HD node transmits at a given time slot. Therefore, an efficient algorithm is proposed to identify the TP, which maximizes the ADP by considering fairness between the number of discovered HD and FD nodes. Numerical results validate the accuracy of the analysis and efficiency of the proposed method.</P>

종합격투기 수련생들의 열정이 수련만족 및 대회참가의도에 미치는 영향

공성배(Kong, Seong-Bae),한대호(Han, Dae-Ho),박성배(Park, Seong-Bae),김종철(Kim, Jong-Chul) 한국체육과학회 2015 한국체육과학회지 Vol.24 No.1

This study examined the effect of Mixed-martial Arts trainee’s passion on training satisfaction and contest participation intention. The research was made with 330 trainees from martial arts gym which are located in Seoul, Kyunggi, and Incheon province. Survey data were collected through survey questionnaires and were analyzed with SPSS 18.0 programs. The results of this study based on above methods and procedures were as followings. First, compulsion and harmony passion which are sub factors of passion had positive effect on physical and social satisfaction which are sub factors of training satisfaction. Meanwhile, harmony passion sub factor of passion had positive effect on social satisfaction. Second, compulsion and harmony passion sub factors of passion had positive effect on contest participation intention. Third, physical and social satisfaction sub factors of training satisfaction had positive effect on contest participation intention.

A 90-day Repeated-Dosed Toxicity Study of Euphorbiae kansui radix Extract in Fischer 344/N Rats

Zhong-Ze Han,Hu-Song Zhang,Ki-Hyun Gil,Joo-Young Lee,Kwang-Han Kong,Myoung-Kyu Han,Hyun-Ju Yang,Hak-Soo Kim,Do-Hyung Kim,Tae-Hwan Ahn,Jin-Sook Bae,Hyun-Kyu Ko,Jung-Woon Lee,Moon-Soon Kim,Si-Whan Song 한국실험동물학회 2008 Laboratory Animal Research Vol.24 No.4

This study was performed to evaluate repeated-dose toxicities of Euphorbiae kansui radix extract in F344/N rats. Euphorbiae kansui radix extract was administered orally to rats at dose levels of 0, 37, 111, 333, 1,000 and 2,000 ㎎/㎏/day. Each group consisted of 10 rats of each gender. The Euphorbiae Kansui, Radix extract was given once a day, 5 times a week, for 90 day repeatedly. This study was conducted in accordance with the Protocol of Korea National Toxicology Program (issued by National Institute of Toxicological Research) and The Standards of Toxicity Study for Medicinal Products (issued by Korea Food and Drug Administration). In the present study, there were no dose-related changes in mortality, clinical signs, body weights, ophthalmoscopy, urine analysis, hematological findings, estrus cycle and sperm examination of all animals treated with Euphorbiae kansui radix extract. There were increases of liver weights in 2,000 ㎎/㎏/day groups of males and in 333, 1,000 and 2,000 ㎎/㎏/day groups of females. There were decreases of alkaline phosphatase levels in 1,000 and 2,000 ㎎/㎏/day groups of both sexes. These results suggest that the oral no-observed-adverse-effect level (NOAEL) of the test item, Euphorbiae kansui radix extract, in rats is 2,000 ㎎/㎏/day in both genders; no-observed-effect level (NOEL) is 1,000 ㎎/㎏/day in male and 111 ㎎/㎏/day in female. The target organs were thought to be liver and thymus.

Establishment of a [¹⁸F]-FDG-PET/MRI Imaging Protocol for Gastric Cancer PDX as a Preclinical Research Tool

Bae, Seong-Woo,Berlth, Felix,Jeong, Kyoung-Yun,Suh, Yun-Suhk,Kong, Seong-Ho,Lee, Hyuk-Joon,Kim, Woo Ho,Chung, June-Key,Yang, Han-Kwang The Korean Gastric Cancer Association 2020 Journal of gastric cancer Vol. No.

Purpose: The utility of 18-fluordesoxyglucose positron emission tomography ([<SUP>18</SUP>F]-FDG-PET) combined with computer tomography or magnetic resonance imaging (MRI) in gastric cancer remains controversial and a rationale for patient selection is desired. This study aims to establish a preclinical patient-derived xenograft (PDX) based [<SUP>18</SUP>F]-FDG-PET/MRI protocol for gastric cancer and compare different PDX models regarding tumor growth and FDG uptake. Materials and Methods: Female BALB/c nu/nu mice were implanted orthotopically and subcutaneously with gastric cancer PDX. [<SUP>18</SUP>F]-FDG-PET/MRI scanning protocol evaluation included different tumor sizes, FDG doses, scanning intervals, and organ-specific uptake. FDG avidity of similar PDX cases were compared between ortho- and heterotopic tumor implantation methods. Microscopic and immunohistochemical investigations were performed to confirm tumor growth and correlate the glycolysis markers glucose transporter 1 (GLUT1) and hexokinase 2 (HK2) with FDG uptake. Results: Organ-specific uptake analysis showed specific FDG avidity of the tumor tissue. Standard scanning protocol was determined to include 150 μCi FDG injection dose and scanning after one hour. Comparison of heterotopic and orthotopic implanted mice revealed a long growth interval for orthotopic models with a high uptake in similar PDX tissues. The H-score of GLUT1 and HK2 expression in tumor cells correlated with the measured maximal standardized uptake value values (GLUT1: Pearson r=0.743, P=0.009; HK2: Pearson r=0.605, P=0.049). Conclusions: This preclinical gastric cancer PDX based [<SUP>18</SUP>F]-FDG-PET/MRI protocol reveals tumor specific FDG uptake and shows correlation to glucose metabolic proteins. Our findings provide a PET/MRI PDX model that can be applicable for translational gastric cancer research.

Poster Session:PS 1130;Gastroenterology (Liver):A Sarcomatoid Carcinoma Arising from Intrahepatic Cholangiocyte: An Unusual Primary Liver Cancer

( Yo Han Kim ),( Kyoung Hwang Shin ),( Sung Hwahn Hahn ),( Jae Hwan Kong ),( Joon Ho Choi ),( Seoung Min Jeon ),( Hyun Deok Shin ),( Suk Bae Kim ),( Jung Eun Shin ),( Hong Ja Kim ),( Il Han Song ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Sarcomatoid carcinoma arising from intrahepatic cholangiocyte, an extremely rare primary liver cancer, has highly invasive and metastatic potential. The pathogenesis of this tumor is unclear, although histogenetic mechanisms such as ‘transformation’, ‘combination’ and ‘collision’ might be suggested to explain the simultaneous co-existence of carcinoma and sarcoma components in the same tumor. Case: A 58 year-old male presented with a hepatic mass that was found during regular health examination. Liver computed tomography (CT) scan revealed 2. 0 cm-sized heterogeneous low density mass without enhancement located on the segment 6. Magnetic resonance imaging showed the tumor of segment 6 with a low-signal intensity in T1-weighted image and a high-signal intensity in T2-weighted image. Positron emission tomography-CT showed a focal hypermetabolic lesion in the same area, with no evidence of distant metastasis. This mass was suspected to be intrahepatic cholangiocarcinoma by ultrasonography-guided needle biopsy, so right posterior sectionectomy was performed. The resected liver showed a well-defi ned whitish or yellowish gray solid mass with a central hemorrhage and necrosis at a subcapsular area of segment 6. Microscopically, the tumor tissue consists of multiple polygonal and pleomorphic cells. The tumor cells were immunohistochemically positive for cytokeratin 19 and vimentin, but negative for Hep-par 1. The patient was confi rmed a defi nitive diagnosis of intrahepatic sarcomatoid carcinoma. After 2 months, the patient developed extensive abdominal metastases and received systemic chemoradiotherapy, resulting in no response visible radiologically. Conclusions: We report an unusual case of sarcomatoid carcinoma of the liver arising from intrahepatic cholangiocyte, confi rmed by immunohistochemical analysis following surgical resection.

청소년들의 프로레슬링에 대한 시청동기가 시청만족과 시청 후 행동에 미치는 영향

한대호(Han, Dae-Ho),공성배(Kong, Seong-Bae),박성진(Park, Seong-Jin) 한국체육과학회 2014 한국체육과학회지 Vol.23 No.6

The purpose of this study is to investigate the effect of adolescents’ pro wrestling viewing motivation on viewing satisfaction and hehavior after viewing. To test this, 312 middle and high school students living in Seoul. Judgement sampling method was used to get results. Conducted data through SPSS 18.0 are as follows: First, amusement & rest which is sub factor of pro wrestling viewing motivation had positive effect on external and internal satisfaction which are suh factors of viewing satisfaction, while preference and escape had positive effect on external satisfaction. Second, amusement & rest and preference suh factors of viewing motivation had positive effect on word-of-mouth intention and reviewing intention sub factors of behavior after watching, but had negative effect on time spending. Third, internal and external satisfaction sub factors of viewing satisfaction had positive effect on reviewing intention, while external satisfaction had positive effect on word-of-mouth intention.

여가스포츠 참여대학생의 자기결정성과 여가만족, 여가지속간의 구조적 관계

공성배(Kong, Seong-Bae),노동연(Roh, Dong-Yun),한대호(Han, Dae-Ho),김보겸(Kim, Bo-Kyoum) 한국체육과학회 2015 한국체육과학회지 Vol.24 No.2

This study examined the structural relationship among self-determination, leisure satisfaction and leisure continuance in University students’ leisure sports participation. 284 University students were sampled from Yongin City in Gyeonggido by using convenient sampling method. To accomplish research purpose, SPSS 18.0(frequency, factor, reliability, correlation analysis) and AMOS 18.0(structural equation modeling) programs are used. Results derived from the researches based on the aforementioned methods and data analyses are as follows: First, relationship, competence, and autonomy which are sub factors of self-determination had positive effect on leisure satisfaction. Second, relationship, competence, and autonomy which are sub factors of self-determination had positive effect on leisure continuance. Third, fun, excitement, pleasure, impressiveness, and vitality which are sub factors of leisure satisfaction had positive effect on leisure continuance.