http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Resource allocation for device-to-device communications underlaying LTE-advanced networks
Phunchongharn, P.,Hossain, E.,Kim, D. I. IEEE 2013 IEEE wireless communications Vol.20 No.4
<P>The Long Term Evolution-Advanced (LTEAdvanced) networks are being developed to provide mobile broadband services for the fourth generation (4G) cellular wireless systems. Deviceto- device (D2D) communications is a promising technique to provide wireless peer-to-peer services and enhance spectrum utilization in the LTE-Advanced networks. In D2D communications, the user equipments (UEs) are allowed to directly communicate between each other by reusing the cellular resources rather than using uplink and downlink resources in the cellular mode when communicating via the base station. However, enabling D2D communications in a cellular network poses two major challenges. First, the interference caused to the cellular users by D2D devices could critically affect the performances of the cellular devices. Second, the minimum quality-of-service (QoS) requirements of D2D communications need to be guaranteed. In this article, we introduce a novel resource allocation scheme (i.e. joint resource block scheduling and power control) for D2D communications in LTE-Advanced networks to maximize the spectrum utilization while addressing the above challenges. First, an overview of LTE-Advanced networks, and architecture and signaling support for provisioning of D2D communications in these networks are described. Furthermore, research issues and the current state-of-the-art of D2D communications are discussed. Then, a resource allocation scheme based on a column generation method is proposed for D2D communications. The objective is to maximize the spectrum utilization by finding the minimum transmission length in terms of time slots for D2D links while protecting the cellular users from harmful interference and guaranteeing the QoS of D2D links. The performance of this scheme is evaluated through simulations.</P>
Hossain, M.A.,Park, J.,Yoo, D.,Baek, Y.k.,Kim, Y.,Kim, S.H.,Lee, D. Elsevier 2016 Current Applied Physics Vol.16 No.3
<P>A series of dye-sensitized solar cells (DSSCs) with different amounts of silver nanoparticles (Ag NPs) coated with a SiO2 layer were prepared as core-shell Ag@SiO2 nanoparticles (Ag@SiO2 NPs). The influence of the amount of Ag@SiO2 NPs on the performance of the DSSCs was investigated. As the amount of Ag@SiO2 NPs increased, the intensity of the light-absorption spectra of the photoanodes gradually increased, whereas the amount of dye absorption was decreased. The short-circuit current density (Jsc), open-circuit voltage (V-oc), and power conversion efficiency (PCE) initially increased gradually and then decreased with increasing amounts of Ag@SiO2 NPs; the charge-transfer resistance (R-2) exhibited the opposite trend. Optimal Jsc, Voc, and PCE values of 13.85 mA/cm(2), 0.66 V, and 6.16%, respectively, were obtained in a DSSC containing 3 wt.% Ag@SiO2 NPs; this PCE is 43.25% higher than that of a photoanode without Ag@SiO2 NPs. The significant improvements in the properties of the optimal DSSC are attributed to the increase in the light coupling, which increased the light absorption of the dye, owing to the localized surface plasmon resonance of the Ag@SiO2 NPs. (C) 2016 Elsevier B.V. All rights reserved.</P>
Hossain M.D.,Khan M.N.I.,Hossain Md Sarowar,Ahned S.J.,Alam M.K.,Liba S.I.,Hakim M.A.,Jamil A.T.M.K. 한국물리학회 2022 Current Applied Physics Vol.43 No.-
This article presents the modification of structure-based magnetic, electronic and transport properties along with the conduction mechanism and its relaxation process in a Ni–Zn–Co ferrite tailored by V5+ substitution at B-site replacing Fe3+ ions. The composition Ni0.7Zn0.2Co0.1Fe2-xVxO4 (0≤ x≤ 0.12) was synthesized by standard solid-state reaction method and all samples were crystallized with a single-phase cubic spinel structure belonging to the Fd3m space group. The lattice constants decreased gradually from 8.3673≽A to 8.3602≽A and the average grain sizes (DSEM) are also decreased from 6.92 μm to 1.99 μm due to V5+ ions substitution at Fe3+ of B-site. However, more than 25% of Fe3+ ions migrate to A-site from B-site due to V5+ substitution at Fe3+ of B-site. In all samples θD does not strictly follow the Anderson’s prediction, rather it monotonically decreases to a low value until x = 0.12. Magnetic phase transition temperature shifted to the lower temperature and the net magnetization (ηeB) decreases due to V5+ substitution in Ni–Zn–Co ferrite. Apart this, during conduction charge carriers should require more energy to jump from one cationic site to other for V5+ substitution in the Ni–Zn–Co ferrite and the activation energy (Ea) is much more higher in V5+ substituted sample. Moreover, long-range interaction with localized relaxation mechanism is observed in V5+ doped samples. The resistance at the grain (Rg) is maximum (243.09 Ω) for the sample x = 0.10 while grain boundary resistance (Rgb) is maximum (5.98×105 Ω) for the sample x = 0.07. However, the higher value of ρdC for x = 0.12 sample ensures to be suitable for electromagnets, transformers, electronic inductors, and at high-frequency applications. Moreover, x = 0.07 sample displays high value of TCR ( -8.6%/K at 418 K) which may be utilized as an infrared detector for night vision bolometer material.
Hossain, D.M. Nazmul,Talukder, Milton,Begum, Most. Kulsum,Paul, Ashit Kumar The Korean Society of Embryo Transfer 2016 한국동물생명공학회지 Vol.31 No.4
This study was carried out to evaluate the influencing factors that affect the reproductive performance of cows at the Monirampur upazila in Jessore district of Bangladesh. A total of 224 cows were brought to the upazila livestock hospital for artificial insemination (AI). The cows were inseminated between 12 to 18 hours from the onset of estrus and data was obtained from the owner. Out of 224 cows, 133 became pregnant and 91 were non pregnant. In this study, the overall pregnancy rate was 59.29%. Among the age variability, the highest pregnancy rate (70.27%) was at the age of 4 years old. In case of breed variation, the highest pregnancy rate was observed in local breed (69.07%) compared with other crossbred cows. Hence the breed variations significantly influence the conception rate of cows. According to the parity, we found that the pregnancy rate was increasing with their parity but decreasing after 4th parity. The highest conception rate was observed in 3rd parity (67.74%) which was significantly higher than that of heifers (Parity-0). Here we also found that the types of bull semen used for AI had no significant effect for pregnancy rate. The skills of AI technician for AI to cows were significantly affecting the pregnancy rate. However, this study is not enough for rating and comment about the reproduction performance of cows. Therefore, further extensive study is needed for rating and recommendation for the cattle up gradation at that particular area.
Prevalence of antibody to and DNA of Lawsonia intracellularis in samples from wild animals in Korea
Hossain, M. D. Mukter,Oh, Yeonsu,Cho, Ho-Seong WILDLIFE DISEASE ASSOCIATION 2016 JOURNAL OF WILDLIFE DISEASES Vol.52 No.4
<P>We evaluated the prevalence of Lawsonia intracellularis infection in three wild animal species in Korea; the Korean water deer (Hydropotes inermis), Siberian roe deer (Capreolus pygargus), and raccoon dogs (Nyctereutes procyonoides). We collected 136 sera and 109 fecal samples from individuals in 10 Wildlife Rescue and Conservation Centers. Serum samples were tested for anti-L. intracellularis antibodies using a blocking enzyme-linked immunosorbent assay (bELISA), and fecal samples were subjected to a real-time PCR assay for L. intracellularis. Thirty-five (25.7%) sera and 36 (33.0%) fecal samples were positive. We found a higher proportion of positive sera (64.7%, chi(2) = 15.439, P< 0.01) and feces (58.8%, chi(2) = 6.126, P< 0.05) in raccoon dogs (chi(2) = 11.855, P< 0.01) than in the other species (20% positive sera and 29% positive feces in Korean water deer; 20% positive sera and 25% positive feces in Siberian roe deer). Our data indicate infection by L. intracellularis in Korean water deer, Siberian roe deer, and raccoon dogs throughout the country. It is imperative to know whether these infected animal species are natural hosts for L. intracellularis in addition to domestic pigs (Sus scrofa domesticus).</P>
D.M. Nazmul Hossain,Milton Talukder,Most. Kulsum Begum,Ashit Kumar Paul 한국수정란이식학회 2016 한국동물생명공학회지 Vol.31 No.4
This study was carried out to evaluate the influencing factors that affect the reproductive performance of cows at the Monirampur upazila in Jessore district of Bangladesh. A total of 224 cows were brought to the upazila livestock hospital for artificial insemination (AI). The cows were inseminated between 12 to 18 hours from the onset of estrus and data was obtained from the owner. Out of 224 cows, 133 became pregnant and 91 were non pregnant. In this study, the overall pregnancy rate was 59.29%. Among the age variability, the highest pregnancy rate (70.27%) was at the age of 4 years old. In case of breed variation, the highest pregnancy rate was observed in local breed (69.07%) compared with other crossbred cows. Hence the breed variations significantly influence the conception rate of cows. According to the parity, we found that the pregnancy rate was increasing with their parity but decreasing after 4th parity. The highest conception rate was observed in 3rd parity (67.74%) which was significantly higher than that of heifers (Parity-0). Here we also found that the types of bull semen used for AI had no significant effect for pregnancy rate. The skills of AI technician for AI to cows were significantly affecting the pregnancy rate. However, this study is not enough for rating and comment about the reproduction performance of cows. Therefore, further extensive study is needed for rating and recommendation for the cattle up gradation at that particular area.
Seo, D.W.,Lim, Y.D.,Hossain, M.A.,Lee, S.H.,Lee, H.C.,Jang, H.H.,Islam, Md.M.,Kim, W.G. Pergamon Press ; Elsevier Science Ltd 2013 International journal of hydrogen energy Vol.38 No.1
Phosphoric acid-doped sulfonated poly(tetra phenyl isoquinoline ether sulfone)s (PA-SPTPIESs) were successfully synthesized for high temperature proton exchange membrane. Poly(tetra phenyl ether ketone sulfone)s (PTPEKS) were prepared from 1,2-bis(4-fluorobenzoyl)-3,4,5,6-tetraphenyl benzene (BFBTPB) and bis(4-fluorohenyl) sulfone with bis(4-hydroxyphenyl) sulfone. The synthesis of the poly(tetra phenyl isoquinoline ether sulfone)s (PTPIESs), was carried out via an intramolecular ring-closure reaction of dibenzoylbenzene of PTPEKS with benzylamine. The sulfonated poly(tetra phenyl isoquinoline ether sulfone)s (SPTPIESs) were obtained by following sulfonation with concentrated sulfuric acid and doped by phosphoric acid. Different contents of sulfonated unit on PTPIESs (8, 12, 16 mol% of BFBTPB) and PA-SPTPIESs were studied by FT-IR, <SUP>1</SUP>H NMR spectroscopy, and thermogravimetric analysis (TGA). Strong acid-base interaction effect between poly benzisoquinoline (PBI) and sulfonic acid groups formed ionic crosslinking network between polymer chains. The ion exchange capacity (IEC) and proton conductivity of PA-SPTPIESs were evaluated with degree of sulfonation and doping of phosphoric acid.