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Inductively Coupled Plasma Etching of GST Thin Films in $Cl_2$/Ar Chemistry ($Cl_2$/Ar 분위기에서 GST 박막의 ICP 에칭)

  • Yoo, Kum-Pyo;Park, Eun-Jin;Kim, Man-Su;Yi, Seung-Hwan;Kwon, Kwang-Ho;Min, Nam-Ki
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1438-1439
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    • 2006
  • $Ge_{2}Sb_{2}Te_5$(GST) thin film at present is a promising candidate for a phase change random access memory (PCRAM) based on the difference in resistivity between the crystalline and amorphous phase. PCRAM is an easy to manufacture, low cost storage technology with a high storage density. Therefore today several major chip in manufacturers are investigating this data storage technique. Recently, A. Pirovano et al. showed that PCRAM can be safely scaled down to the 65 nm technology node. G. T Jeonget al. suggested that physical limit of PRAM scaling will be around 10 nm node. Etching process of GST thin ra films below 100 nm range becomes more challenging. However, not much information is available in this area. In this work, we report on a parametric study of ICP etching of GST thin films in $Cl_2$/Ar chemistry. The etching characteristics of $Ge_{2}Sb_{2}Te_5$ thin films were investigated using an inductively coupled plasma (ICP) of $Cl_2$/Ar gas mixture. The etch rate of the GST films increased with increasing $Cl_2$ flow rate, source and bias powers, and pressure. The selectivity of GST over the $SiO_2$ films was higher than 10:1. X-ray photoelectron spectroscopy(XPS) was performed to examine the chemical species present in the etched surface of GST thin films. XPS results showed that the etch rate-determining element among the Ge, Sb, and Te was Te in the $Cl_2$/Ar plasma.

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A Clinical Study on the Effects of Intravenous Wild ginseng Herbal Acupuncture on the Human Body (정맥 주입용 산삼약침이 인체에 미치는 영향에 관한 임상적 연구)

  • Kwon, Ki-Rok
    • Journal of Pharmacopuncture
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    • v.7 no.1 s.12
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    • pp.15-26
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    • 2004
  • Background : This study was conducted to evaluate the effects of wild ginseng herbal acupuncture developed for the intravenous use. Healthy male and female volunteers(n=57) went through Randomized Control Trials(RCT). Methods : For those who are under a medication due to common cold or other illnesses were excluded in the primary stage and the subjects with possible abnormalities in the pre-screening process were also excluded in the secondary stage. Then the examination groups were determined by random sampling. Experiment groups were divided into Normal saline injection group(control group), cultivated wild ginseng herbal acupuncture group(experiment group 1) and natural wild ginseng herbal acupuncture group(experiment group 2) Blood tension, body temperature, pulse, and other criteria were measured and analyzed. Results : 1. Intravenous injection of cultivated wild ginseng herbal acupuncture and natural wild ginseng herbal acupuncture didn't cause significant changes in the blood tension, pulse, body temperature, and etc. 2. No significant differences were witnessed in CBC, ESR, biochemistry of blood test and UA between the experiment groups. 3. No significant changes were noted in the thermography before and after the test in the experiment groups. 4. Some of the common physical changes occurring during and after the administration were fatigue, chest distension, and headache in all of the experiment groups. 5. Comparing general condition after one week from the termination of administration, the control group showed worst condition while as the natural wild ginseng herbal acupuncture group displayed best condition. Conclusion : From the above results, we can carefully deduce that the intravenous injection of the wild ginseng herbal acupuncture didn't show significant differences compared to injection of the normal saline. We can infer it is safe on the human body and further studies and reports must be followed.

A Sttudy on the Optimal estimation of the Fixed Position and Compterization of the Navigational Calculations (실측선위의 정도개선과 항법계산의 전산화에 관한 연구)

  • 하주식;윤여정
    • Journal of the Korean Institute of Navigation
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    • v.7 no.2
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    • pp.1-45
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    • 1983
  • This paper concerns the applications of the Kalman filter to navigation and the develment of computer programs of the navigational calculations. Methods to apply the Kalman filter to celestial fix, fix by cross bearing and cocked hat are proposed, and numerical simulations under various noise conditiions are conducted. The accuracy of the optimal positions obtained by the Kalman filter is compared with that of the fixed positiions by radial error method. In the case of celestial fix, an algorithm to estimate the optimal positions by using the linear Kalman filter is presented. The optimal positions by the Kalman filter are compared with the running fixes and with the most probable positions obtained from a single line of position. It is confirmed that the resutls of the proposed method are more accurate than the others. In practical piloting, bearings are generally measured intermittently and the measurement process is nonlinear. It is, therefore, difficult for us to apply the Kalman filter to fix by cross bearing. In order to be used in such an unfavorable case, the extended Kalman filter is revised and the aplicability of the revised extended Kalman filter is checked by numerical simulation under various noise conditions. In a cocked hat, an inside or outside fix is dependent only upon azimuth spread, if the error of each line of position is assumed to be equal both in magnitude and sign. A new technique of selecting a ship's position between an inside fix and an outside fix in a cocked hat by using fix determinant derived from the equation of three lines of position is also presented. The relations among the optimal position by Kalman filter, incentre (or excentre) and random error centtre of the cocked hat are discussed theoretically and the accuracy of the optimal position is compared with that of the others by numerical simulation.

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Genome Analysis Pipeline I/O Workload Analysis (유전체 분석 파이프라인의 I/O 워크로드 분석)

  • Lim, Kyeongyeol;Kim, Dongoh;Kim, Hongyeon;Park, Geehan;Choi, Minseok;Won, Youjip
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.2
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    • pp.123-130
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    • 2013
  • As size of genomic data is increasing rapidly, the needs for high-performance computing system to process and store genomic data is also increasing. In this paper, we captured I/O trace of a system which analyzed 500 million sequence reads data in Genome analysis pipeline for 86 hours. The workload created 630 file with size of 1031.7 Gbyte and deleted 535 file with size of 91.4 GByte. What is interesting in this workload is that 80% of all accesses are from only two files among 654 files in the system. Size of read and write request in the workload was larger than 512 KByte and 1 Mbyte, respectively. Majority of read write operations show random and sequential patterns, respectively. Throughput and bandwidth observed in each processing phase was different from each other.

Abnormal Behavior Recognition Based on Spatio-temporal Context

  • Yang, Yuanfeng;Li, Lin;Liu, Zhaobin;Liu, Gang
    • Journal of Information Processing Systems
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    • v.16 no.3
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    • pp.612-628
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    • 2020
  • This paper presents a new approach for detecting abnormal behaviors in complex surveillance scenes where anomalies are subtle and difficult to distinguish due to the intricate correlations among multiple objects' behaviors. Specifically, a cascaded probabilistic topic model was put forward for learning the spatial context of local behavior and the temporal context of global behavior in two different stages. In the first stage of topic modeling, unlike the existing approaches using either optical flows or complete trajectories, spatio-temporal correlations between the trajectory fragments in video clips were modeled by the latent Dirichlet allocation (LDA) topic model based on Markov random fields to obtain the spatial context of local behavior in each video clip. The local behavior topic categories were then obtained by exploiting the spectral clustering algorithm. Based on the construction of a dictionary through the process of local behavior topic clustering, the second phase of the LDA topic model learns the correlations of global behaviors and temporal context. In particular, an abnormal behavior recognition method was developed based on the learned spatio-temporal context of behaviors. The specific identification method adopts a top-down strategy and consists of two stages: anomaly recognition of video clip and anomalous behavior recognition within each video clip. Evaluation was performed using the validity of spatio-temporal context learning for local behavior topics and abnormal behavior recognition. Furthermore, the performance of the proposed approach in abnormal behavior recognition improved effectively and significantly in complex surveillance scenes.

Estimating Economic Values of Parcel Service Attributes (택배 서비스 속성별 경제적 가치 추정)

  • Han, Sang-Yong;Kim, Yong-Mi
    • Journal of Korean Society of Transportation
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    • v.28 no.5
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    • pp.65-75
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    • 2010
  • The objective of this paper is to quantify economic values of parcel service attributes (safety, reliability, quickness, and kindness and customer service) using the contingent choice method and to investigate impact factors (such as sex, age, and education), which influence choice of desirable parcel services. As empirical results, the marginal willingness-to-pay for multiple attributes of parcel service is calculated as about 2,349.6 KRW for the safety attribute, about 829.3 KRW for the reliability attribute, about 588.5 KRW for the quickness attribute, and about 358.8 KRW for the kindness and customer service attribute, according to the estimation model without covariates. The overall results indicate that the safety attribute ranks highest among parcel service attributes, followed by the reliability attribute, quickness attribute, and kindness and customer service attribute. These results can be useful in the decision-making process for establishing desirable pricing policies for parcel service.

Application of Generalized Transmissivity Decreasing Function in TOPMODEL Operation (TOPMODEL 투수량계수 감소함수 일반화과정의 적용에 관한 연구)

  • Jeong, Seon-Hui;Kim, Sang-Hyeon
    • Journal of Korea Water Resources Association
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    • v.32 no.6
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    • pp.637-647
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    • 1999
  • This study investigated the applicability of generalized TOPMODEL approach which introduces the power law of decreasing transimissivity with depth instead of the traditional exponential decreasing function. The 50m digital elevation model(DEM) of Dongkog subwatershed at Wichon Test Watershed was used to perform runoff simulation. Random number generation algorithm was integrated into the calibration process for the reliable of model performance. General power law version of TOPMODEL with exponent 2 and 3 showed higher simulation efficiency than other the approaches. This results from the fact that the power law models with exponent 2 and 3 can represent the soil characteristics of study area better than other models.

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Development of Issue-centered Small-group Debate Program for the Introduction to Traditional Korean Medicine (한의학 입문과정에서의 소집단 찬반토론 개발 연구)

  • Lee, Soo-Jin;Lee, Yong-Jae;Kim, Byung-Joo;Kwon, Young-Kyu;Chae, Han
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.2
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    • pp.326-333
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    • 2011
  • This study was to develop an issue-centered small-group competing-debate program for the Introduction to Traditional Korean Medicine curriculum in School of Korean Medicine, Pusan National University. This debate program has student-, process- and depth-focused characteristics with critical-thinking perspectives. We employed random assignment of the position, submission of the presentation data prior to the debate, and individual result report to assess debate quality and participation of the students. This program was effective educational program for the understanding of traditional Korean medicine-related subjects. 56.7% of the students showed "Yes (>7 out of 10)" to the achievements of the program objectives, and 62.2% reported "much helpful (>7 out of 10)" to the usefulness of this program. We also found that this debate program would be specifically useful for critical reviewing of subjects which students have known superficially. This study will contribute to the development and improvement of efficacious educational curriculum for Korean Medicine by providing practical reference and template with self-directed group debate program.

Comparison of Fatigue Damage Models of Spread Mooring Line for Floating Type Offshore Plant (부유식 해양플랜트 다점 계류라인의 피로손상모델 비교)

  • Park, Jun-Bum;Kim, Kookhyun;Kim, Kyung-Su;Ko, Dae-Eun
    • Journal of Ocean Engineering and Technology
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    • v.27 no.5
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    • pp.63-69
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    • 2013
  • The mooring lines of a floating type offshore plant are known to show wide banded and bimodal responses. These phenomena come from a combination of low and high frequency random load components, which are derived from the drift-restoring motion characteristic and wind- sea, respectively. In this study, fatigue models were applied to predict the fatigue damage of mooring lines under those loads, and the result were compared. For this purpose, seven different fatigue damage prediction models were reviewed, including mathematical formula. A FPSO (floating, production, storage, and offloading) with a $4{\times}4$ spread catenary mooring system was selected as a numerical model, which was already installed at an offshore area of West Africa. Four load cases with different combinations of wave and wind spectra were considered, and the fatigue damage to each mooring line was estimated. The rain flow fatigue damage for the time process of the mooring tension response was compared with the results estimated by all the fatigue damage prediction models. The results showed that both Benasciutti-Tovo and JB models could most accurately predict wide banded bimodal fatigue damage to a mooring system.

Detection of unexploded ordnance (UXO) using marine magnetic gradiometer data (해양 자력구배 탐사자료를 이용한 UXO 탐지)

  • Salem Ahmed;Hamada Toshio;Asahina Joseph Kiyoshi;Ushijima Keisuke
    • Geophysics and Geophysical Exploration
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    • v.8 no.1
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    • pp.97-103
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    • 2005
  • Recent development of marine magnetic gradient systems, using arrays of sensors, has made it possible to survey large contaminated areas very quickly. However, underwater Unexploded Ordnances (UXO) can be moved by water currents. Because of this mobility, the cleanup process in such situations becomes dynamic rather than static. This implies that detection should occur in near real-time for successful remediation. Therefore, there is a need for a fast interpretation method to rapidly detect signatures of underwater objects in marine magnetic data. In this paper, we present a fast method for location and characterization of underwater UXOs. The approach utilises gradient interpretation techniques (analytic signal and Euler methods) to locate the objects precisely. Then, using an iterative linear least-squares technique, we obtain the magnetization characteristics of the sources. The approach was applied to a theoretical marine magnetic anomaly, with random errors, over a known source. We demonstrate the practical utility of the method using marine magnetic gradient data from Japan.