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Wi-Fi Direct 망을 위한 부하량 예측 기반의 전력 절감 기법 (Adaptive Power Saving Protocol Based on Traffic Estimation for Wi-Fi Direct Networks)

  • 유홍석;박양우;이채수;윤태진
    • 대한임베디드공학회논문지
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    • 제10권4호
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    • pp.207-212
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    • 2015
  • Wi-Fi Direct allows battery powered mobile devices to form a wireless ad hoc network. Since one member of the network called Group Owner (GO) takes the role of managing the network, the network lifetime is mainly affected by the energy efficiency of GO. Hence, Wi-Fi Direct defines power saving schemes that allow GO to save the energy by turning off its radio interface during the periods called absence periods. However, the Wi-Fi Direct specification does not specify how to set parameters (denoted by PS parameters) determining the schedule of the absence periods. In this paper, we therefore propose a novel traffic-aware power saving scheme for Wi-Fi Direct networks. In particular, the proposed scheme estimates the application-level traffic load and adaptively tunes the PS parameters according to the estimated value.

듀얼첩간 위상차이를 이용한 저복잡도 FMCW 감시 레이더 알고리즘 (Low Complexity FMCW Surveillance Radar Algorithm Using Phase Difference of Dual Chirps)

  • 진영석;현유진;김상동;김봉석;이종훈
    • 대한임베디드공학회논문지
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    • 제12권2호
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    • pp.71-77
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    • 2017
  • This paper proposes a low complexity frequency modulated continuous wave (FMCW) surveillance radar algorithm. In the conventional surveillance radar systems, the two dimensional (2D) fast Fourier transform (FFT) method is usually employed in order to detect the distance and velocity of the targets. However, in a surveillance radar systems, it is more important to immediately detect the presence or absence of the targets, rather than accurately detecting the distance or speed information of the target. In the proposed algorithm, in order to immediately detect the presence or absence of targets, 1D FFT is performed on the first and M-th bit signals among a total of M beat signals and then a phase change between two FFT outputs is observed. The range of target is estimated only when the phase change occurs. By doing so, the proposed algorithm achieves a significantly lower complexity compared to the conventional surveillance scheme using 2D FFT. In addition, show in order to verify the performance of the proposed algorithm, the simulation and the experiment results are performed using 24GHz FMCW radar module.

Real-time Evolution of Poly (3-hexylthiophene) type-II Phase in P3HT:PCBM Blend thin films

  • 이현휘;이시우;금희성;김한성;김제한;이동렬;김효정
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.168.2-168.2
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    • 2015
  • We observed the temperature-dependent evolution and behavior of P3HT type-II phase during a real time annealing process from a cryo-cooled low temperature in the absence and presence of an Al electrode. A poly (3-hexylthiophene) (P3HT) Type-II phase in the P3HT:PCBM films started to form near at $-10^{\circ}C$, regardless of Al layer presence. In the absence of an Al layer, type-II phase was extinct at $30^{\circ}C$. However, the extinction temperature was extended to $50^{\circ}C$ in the presence of the Al layer. Simultaneously, combined with the type-II phase, a 1:3 ordered P3HT type-II (1/3,0,0) super-lattice peak evolved. These type-II domains tended to be formed near the Al electrode layer with higher aligned status than host P3HT crystals.

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간호진단의 임상적용 활성화를 위한 기초조사 연구 (A Survey Study of Nursing Diagnosis Use in Clinical Practice)

  • 최영희;이향련;김혜숙;김소선;박광옥
    • 대한간호학회지
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    • 제26권4호
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    • pp.930-945
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    • 1996
  • The purpose of this study was to identify the degree to which nursing diagnoses accepted by NANDA are used and to identify problems in application of nursing diagnoses in clinical practice. With the expanding potential for computerization of nursing diagnosis, the survey also included data on the present status of hospital computerization and willingness to use computerized nursing diagnoses. The data collection was done from July 1 to August 3, 1996 using structured questionnaires. The questionnaires were mailed to 1,126 head nurses working in 44 hospitals with on occupacy of over 500 beds located in Korea, of these, 883 were returned from 40 hospitals. Among the 883 questionnaires, 867 were used for the analysis. The results of the analysis are as follows 1. Among 109 nursing diagnoses, pain, constipation, diarrhea, hyperthermia, high risk for infection, sleep pattern disturbance, and anxiety, chronic pain, altered urinary elimination, and altered nutrition : less than body requirements were the ten most frequently used diagnoses. 2. The primary problem in the use of nursing diagnoses was lack of time and personnel. Others were lack of knowledge and motivation, absence of protocols and absence of the appropriate methods to apply nursing diagnoses. 3. Among the 40 hospitals, 27 hospitals used a computerized system and expressed willingness to utilize the computerized system of nursing diagnoses that is planned for the future.

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Evaluation of the Genetic Toxicity of Synthetic Chemicals (IV) - in vitro Chromosomal Aberration Assay with 18 Chemicals in Chinese Hamster Lung Cells -

  • Ryu, Jae-Chun;Kim, Kyung-Ran;Kim, Youn-Jung
    • 한국환경성돌연변이발암원학회지
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    • 제22권3호
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    • pp.149-156
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    • 2002
  • The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, to regulate and to evaluate the chemical hazard will be important to environment and human health. The clastogenicity of 18 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. 4-Chloro-3,5-dimethyl phenol (CAS No. 88-04-0) induced chromosomal aberrations with significance at the concentration of 15.7 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. Phenoxybenzene (CAS No. 101-84-8) which is one of the most cytotoxic chemical among 18 chemicals tested revealed no clastogenicity in the range of 0.11-0.43 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. From the results of chromosomal aberration assay with 18 synthetic chemicals in Chinese hamster lung cells in vitro, 4-chloro-3,5-dimethyl phenol (CAS No. 88-04-0) revealed weak positive clastogenic results in this study.

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이중채널 잡음음성인식을 위한 공간정보를 이용한 통계모델 기반 음성구간 검출 (Statistical Model-Based Voice Activity Detection Using Spatial Cues for Dual-Channel Noisy Speech Recognition)

  • 신민화;박지훈;김홍국;이연우;이성로
    • 말소리와 음성과학
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    • 제2권3호
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    • pp.141-148
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    • 2010
  • In this paper, voice activity detection (VAD) for dual-channel noisy speech recognition is proposed in which spatial cues are employed. In the proposed method, a probability model for speech presence/absence is constructed using spatial cues obtained from dual-channel input signal, and a speech activity interval is detected through this probability model. In particular, spatial cues are composed of interaural time differences and interaural level differences of dual-channel speech signals, and the probability model for speech presence/absence is based on a Gaussian kernel density. In order to evaluate the performance of the proposed VAD method, speech recognition is performed for speech segments that only include speech intervals detected by the proposed VAD method. The performance of the proposed method is compared with those of several methods such as an SNR-based method, a direction of arrival (DOA) based method, and a phase vector based method. It is shown from the speech recognition experiments that the proposed method outperforms conventional methods by providing relative word error rates reductions of 11.68%, 41.92%, and 10.15% compared with SNR-based, DOA-based, and phase vector based method, respectively.

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관상정맥동불형성, 좌상공정맥좌심방환류, 동맥관개존을 동반한 심방중격결손의 체험예 (A Persistent Left Superior Vena Cava Draining into Left Atrium Associated with ASD, Absence of the Coronary Sinus Ostium and PDA Report of One Case)

  • 조중구
    • Journal of Chest Surgery
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    • 제15권2호
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    • pp.243-249
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    • 1982
  • A persistent left superior vena cava draining into the left atrium associated with atresia of the coronary sinus-ostium, ASD, and PDA is a rare congenital anomaly. The patient was a 4 year-old female whose complaints were frequent URI and exertional dyspnea. The congenital heart anomaly was suspected at 2 months of her age. Chest films showed cardiomegaly [C-T ratio, 75%]. EKG, Echocardiography, cardiac catheterization and angiocardiography were performed. Open heart surgery was done under impression of LV-RA shunt, bilateral superior vena cavae, and ASD. At the time of operation, huge LA and RA, inferior vena caval defect of a secundum type ASD [1.5 x 3cm in diameter], absence of innominate vein, atresia of the coronary sinus-ostium, and persistent LSVC draining into LA were noted. Direct suture closure of ASD and ligation of LSVC were done. The patient`s postoperative course was somewhat eventful: systolic murmur at apex remained. Four months after the operation, congestive heart failure attacked a few times. PDA that was overlooked at the time of open heart surgery was detected through postoperative cardiac catheterization in.4 months later. Emergent operation for closure of PDA was performed on the day of recatheterization. After that, patient`s heart failure was easily controlled without any notable problem.

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SENSITIZED PHOTOINITIATING SYSTEM USED IN PHOTOPOLYMER FILMS

  • Liu, A.D;Trifunac, A.D;Krongauz, V.V.
    • 한국진공학회지
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    • 제7권s1호
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    • pp.20-24
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    • 1998
  • Photploymer films are widely used in printing and electronic industries, and their usage is expanding to encompass holography, data storage and data processing, optical waveguides and compact disks, etc. One of widely used photoplymerization initiator, 20chloro-hexaarylbiimidazole (o-Cl-HABI), is studied by laser flash photolysis in dichloromethane solution in the absence and presence of the visible light photosensitizing dye, 2, 5-bis[(2, 3, 6, 7 -tetrahydro- 1H, 5H -benzo [i, j,] quinolizin -1-yl) methylene]-cyclopenta-none, (JAW). In the presence of JAW, an increase in triarylimidazolyl radicals L.formation is observed in relative to the absence of JAW. The mechanism of this photosensitizing dissociation is concluded as the dissociation of the o-Cl-HABI radical anion formed by the electron transfer from excited singlet state of JAW to o-Cl-HABI. The observed formation of L.radicals exhibits a linear dependence on o-Cl-HABI concentration. The rate constant of electron transfer obtained from this dependence is equal to (1.0$\pm$0.2) x $10^9 M^{-1}s^{-1}$. No reaction between the excited triplet state of JAW and o-Cl-HABI is found.

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하악 제 3 대구치유무 및 매복정도가 하악과두 골절에 미치는 영향 (THE INFLUENCE OF THE PRESENCE AND IMPACTED STATE OF MANDIBULAR THIRD MOLARS ON THE INCIDENCE OF MANDIBULAR CONDYLE FRACTURE)

  • 오제경;차두원;김진수
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제28권6호
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    • pp.565-569
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    • 2006
  • The purpose of this study was to assess the influence of the presence and impacted state of the mandibular third molars on the incidence of mandibular condyle fracture. A retrospective study was designed for patients presenting to the Department of Oral and Maxillofacial Surgery, Kyungpook National University Hospital and Tae-gu Fatima Hospital for treatment of mandibular fractures from January 2003 to January 2006. The independent variables in this study were the presence, degree of impaction of third molars, and the outcome variables were the incidence of mandibular condyle fractures. Hospital charts and panoramic radiographs were used to determine and classify these variables. The demographic data included age, sex, mechanisms of injuries and number of mandibular condyle fractures. The study sample comprised 136 mandibular condyle fractures in 105 patients. Result of this study demonstrated a statistically significant difference in ipsilateral condyle fractures and mandibular third molar absence(P=0.032) and bilateral condyle fractures without another fracture and mandibular third molar absence(P=0.028).

착의량이 유아건강에 미치는 영향 (The Effects on Clothing Weight in the Health State of the Kindergartners)

  • 이원자;최정화
    • 한국의류학회지
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    • 제13권1호
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    • pp.13-33
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    • 1989
  • The purpose of this study is to obtain the effects on clothing weight in the health state of the kindergartners. So 1 divided 140 kindergartners into 3 groups. A not trained of light wearing in the control group, B the semi-experimetnal group, C the experimental group. In the field surveys conducted their monthly clothing weight and anthropometric measurements, physique index (obesity index) and motor-ability and rate of cold contraction and of absence, Cornell Medical index from Jun, 1986 to Feb, 1987 in Seoul. 1) The experimental group was even less clothing than the control group in clothing weight during the training period. 2) All the experimental group droped conspicuosly the rate of cold contraction and absence during this period. 3) After this training, the experimental group was better than semi-experimental group and control group in motor-ability especially in standing broad jump, flexibility and tennis ball throw, 25 meter dash. 4) But, 1 could not find the different of anthropometric-measurements, physique-index about this train.

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