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>

Characterization of Interface States in MOS Systems by Using Photonic High-Frequency Capacitance-Voltage Responses

S.J.Song,H.T.Kim,S.S.Chi,M.S.Kim,W.S.Chang,S.D.Cho,H.T.Shin,T.E.Kim,H.J.Kang,D.J.Kim,D.M.Kim 한국물리학회 2002 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.41 No.6

Based on the photonic high-frequency capacitance-voltage response of Metal-Oxide-Semiconductor capacitors, we report an improved characterization method for the analyzing of interface states in MOS systems. An optical source with a photonic energy $E_{ph}$ = 0.943 eV ($\lambda$ = 1314.5 nm) is employed for photonic deep-depletion (fast sweep rate) high-frequency Capacitance-Voltage (photonic DD HF-CV) characterization of interface states distributed in the photo-responsive energy band. Using the photonic DD HF-CV characterization, we obtained a U-shaped distribution of $D_{it}$ over ($E_V + E_g/2 - q\phi_f) < E_t < (E_V + E_g/2 - q\phi_f + q\phi_S$) for N-type Metal-Oxide-Semiconductor capacitors and ($E_C - E_g/2 - q\phi_f + q\phi_S) < E_t < (E_C - E_g/2 - q\phi_f$) for P-type Metal-Oxide-Semiconductor capacitors.

Potential roles of D-serine and serine racemase in experimental temporal lobe epilepsy

Ryu, H.J.,Kim, J.-E.,Yeo, S.-I.,Kim, D.-S.,Kwon, O.-S.,Choi, S.Y.,Kang, T.-C. Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of neuroscience research Vol.88 No.11

<P>To confirm the roles of D-serinergic gliotransmission in epilepsy, we investigated the relationship between spatiotemporally specific glial responses and the D-serine/serine racemase system in mesial temporal structures following status epilepticus (SE). In control animals, D-serine and serine racemase immunoreactivities were detected mainly in astrocytes. After SE, D-serine and serine racemase immunoreactivities were increased in astrocytes. Double-immunofluorescence study revealed that up-regulation of serine racemase immunoreactivity was relevant not to D-serine immunoreactivity but to nestin or vimentin immunoreactivity. Neither D-serine nor serine racemase was found in naïve or reactive microglia. In addition, phosphorylated N-methyl-D-aspartate (NMDA) receptor subunit 1 (pNR1-Ser896) immunoreactivity in the hippocampus was increased compared with controls. Increased D-serine immunoreactivity showed direct correlation with the phosphorylation of Ser896 of NR1. Given the findings of our previous study, these findings suggest that D-serine and serine racemase in astrocytes may play roles in neuronal hyperexcitability via a cooperative activation of NMDA receptors. Furthermore, serine racemase may be involved in migration and differentiation of immature astrocytes, which is relevant to reactive astrogliosis. © 2010 Wiley-Liss, Inc.</P>

d-pinitol regulates Th1/Th2 balance via suppressing Th2 immune response in ovalbumin-induced asthma

Lee, J.S.,Lee, C.M.,Jeong, Y.I.,Jung, I.D.,Kim, B.H.,Seong, E.Y.,Kim, J.I.,Choi, I.W.,Chung, H.Y.,Park, Y.M. North-Holland Pub ; Elsevier Science Ltd 2007 FEBS letters Vol.581 No.1

d-pinitol has been demonstrated to exert insulin-like and anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. Recently, it was shown that T-bet and GATA-3 are master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether d-pinitol regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in OVA-induced asthma model mice. We also examined to ascertain whether d-pinitol could influence eosinophil peroxidase (EPO) activity. After being sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions. These reactions included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung tissue around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of d-pinitol before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that d-pinitol plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of d-pinitol in terms of its effects in a murine model of asthma, and also broaden current perspectives in our understanding of the immunopharmacological functions of d-pinitol.

Optical subthreshold current method for extracting the interface states in MOS systems

Kim, M.S.,Nam, I.C.,Kim, H.T.,Shin, H.T.,Kim, T.E.,Park, H.S.,Kim, K.S.,Kim, K.H.,Choi, J.B.,Min, K.S.,Kim, D.J.,Kang, D.W.,Kim, D.M. IEEE 2004 IEEE electron device letters Vol.25 No.2

Optical subthreshold current method (OSCM) is proposed for characterizing the interface states in MOS systems using the current-voltage characteristics under a photonic excitation. An optical source with a subbandgap (E<SUB>ph</SUB>>E<SUB>g</SUB>) photonic energy (E<SUB>ph</SUB>=0.943 eV, P<SUB>opt</SUB>=+5 dBm), which is less than the silicon bandgap (E<SUB>g</SUB>=1.12;eV), is employed for the optical subthreshold current characterization of interface states in the photoresponsive energy band. We applied the OSCM method under a subbandgap photonic excitation to MOS systems with a poly-Si gate and verified a U-shaped distribution of interface trap density D<SUB>it</SUB>=10<SUP>10</SUP>∼10<SUP>12</SUP> eV<SUP>-1</SUP>cm<SUP>-2</SUP> for n- and p-type MOSFETs with W/L=30 μm/1.2 μm.

Validation of the metabolic pathway of the alginate-derived monomer in Saccharophagus degradans 2-40^T by gas chromatography-mass spectrometry

Kim, D.H.,Wang, D.,Yun, E.J.,Kim, S.,Kim, S.R.,Kim, K.H. Elsevier Applied Science 2016 Process biochemistry Vol.51 No.10

Marine macroalgae are potential resources for the sustainable production of biofuels and bio-based chemicals. Alginate, a major component of brown macroalgae, consists of two uronate monomers, which are further non-enzymatically converted to 4-deoxy-l-erythro-5-hexoseulose uronate (DEH). In several marine bacteria, DEH is known to be metabolized via three enzymatic steps, consisting of DEH reductase, 2-keto-3-deoxy-d-gluconate (KDG) kinase, and 2-keto-3-deoxy-phosphogluconate (KDPG) aldolase, which yields two glycolytic intermediates: d-glyceraldehyde-3-phosphate and pyruvate. However, such functions of these enzymes for the DEH pathway have rarely been experimentally validated. In the present study, the DEH metabolic pathway was investigated in Saccharophagus degradans 2-40<SUP>T</SUP>, a marine bacterium that utilizes alginate. Through in vitro tests assisted by gas chromatography/mass spectrometry and gas chromatography/time-of-flight mass spectrometry, the purified enzymes were functionally confirmed and annotated as dehR, kdgK, and kdpgA, respectively. In conclusion, we report the in vitro validation of the metabolic pathway of DEH monomerized from alginate.

Pulse Shape Discrimination of Nuclear Recoil and Electron Recoil Events With a NaI(Tl) Crystal for Dark Matter Search

Kim, K. W.,Adhikari, G.,Adhikari, P.,Choi, S.,Ha, C.,Hahn, I. S.,Jeon, E. J.,Joo, H. W.,Kang, W. G.,Kim, H. J.,Kim, N. Y.,Kim, S. K.,Kim, Y. D.,Kim, Y. H.,Lee, H. S.,Lee, M. H.,Leonard, D. S.,Oh, S. Y IEEE 2016 IEEE transactions on nuclear science Vol.63 No.2

<P>In order to investigate discrimination between nuclear recoil and electron recoil events for the KIMS-NaI dark matter search experiment, we measured the pulse shapes produced by neutrons and gamma rays in a NaI(Tl) crystal. Relatively good pulse shape discrimination (PSD) power due to high light output of recently developed crystals makes it possible to test whether the annual modulation signal observed by the DAMA/LIBRA experiment is caused by nuclear recoil events. We applied the PSD to underground data taken with a 9.15 kg low-background and high-light-output NaI(Tl) crystal for 134 days. Good agreement between underground data and electron recoil events was observed.</P>

화력발전소의 대기오염물질 배출계수 산정 연구

김대곤,엄윤성,홍지형,이석조,석광설,이대균,이은정,방선애 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.3

The main purpose of this study was to characterize the air pollutants emission factors in electric power plant (EPP) using fossil fuels. The electric power plant is a major air pollution source, thus knowing the emission characteristics of electric power plant is very important to develop a control strategy. The major air pollutants of concern from EPP stacks are particulate matter (PM), sulfur oxides (SOx), nitrogen oxides (NOx), carbon monoxide (CO) and heavy metals. Throughout the study. the following results arc estimated: - PM : 8.671E-05∼8.724E+01 PM emission (kg) per fuel burned (ton) - SOx: 4.749E-04∼7.877E+01 SOx emission (kg) per fuel burned (ton) - NOx : 1.578E-02∼9.857E+00 NOx emission (kg) per fuel burned (ton) - CO : 3.800E-04∼1.291E+00 CO emission (kg) per fuel burned (ton) - Hg : 1.220E+01∼3.108E+02 Hg emission (mg) per fuel burned (ton) From the statistical analysis by Wilcoxon signed ranks test between the emission factors of ours and U.S. EPA's. we can yielded that: p > 0.05.

간호대학생의 전공만족도와 간호전문직관의 관계 : 일대학 간호대학생을 대상으로

고정은,김미희,김은진,김혜지,엄지은,이행아,장누리,장동은 이화여자대학교 간호학회 2011 이화간호학회지 Vol.- No.45

PURPOSE : This study purposed to examine the relation between nursing college students' major satisfaction and their nursing professionalism. METHOD : We collected data from 197 nursing students at a college in Seoul using a structured questionnaire from the 6th to 13th. The collected data was analyzed by SPSS 17.0. RESULT : 1. The mean score of major satisfaction was 3.54±49 and that of nursing professionalism was 3.52±46. Among the sub-areas of major satisfaction, satisfaction with career investigation was highest. In addition, among the sub-areas of nursing professionalism, the specialty of nursing was highest. 2. Major satisfaction was higher in those from the Department of Natural Science, with a nurse in their family members and it was also significantly different according to the motive for choosing nursing. Nursing professionalism was higher in those with a nurse in their family members and it was also significantly different according to the motive for choosing. 3. A statistically significant positive correlation was observed between the subjects' major satisfaction and their nursing professionalism. The sub-area of major satisfaction in the highest correlation with nursing professionalism was 'satisfaction with perception', and the sub-area of nursing professionalism in the highest correlation with major satisfaction was 'professional self-concept' CONCLUSION : A significant positive correlation was observed between major satisfaction and nursing professionalism, and this raises the necessity for maintaining high major satisfaction so that nursing students may establish positive nursing professionalism through their college study.

자외선 조사간격이 브로일러 병아리 다리 피부의 비타민 D3 함량에 미치는 영향

장윤환(Y . H . Chiang),조인호(I . H . Cho),여영수(Y . S . Yeoh),이은택(E .T . Lee),배은경(E . K . Bae),김중달(J . D . Kim),M . F . Holick(M . F . Holicka) 한국영양사료학회 1993 韓國營養飼料學會誌 Vol.17 No.6