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An Analysis on the Researches Using Biological Measurement in Major Korean Nursing Journals (국내 주요 간호학회지에 게재된 생물학적 측정법(Biological measurement)을 이용한 연구에 대한 분석)

  • Kim, Joo-Hyun;Choe, Myoung-Ae;Kim, Yun-Kyung;Kim, Jin-Hak;Kim, Hee-Seung;Park, Mi-Jung;Shin, Gi-Soo;An, Gyeong-Ju;Lee, Yun-Mi;Lee, Kyung-Sook;Jeong, Jae-Sim;Chae, Young-Ran;Hong, Hae-Sook
    • Journal of Korean Biological Nursing Science
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    • v.8 no.2
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    • pp.61-72
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    • 2006
  • Purpose: This study was to examine the frequency, distribution and characteristics of researches using biological measurement published from 2000 to 2004 in 10 major nursing journals in Korea, Design: Literature analysis. Method: Journals including papers using biological measurements, publishing year, research design and outcome variables were analyzed. Results: 1. Researches using biological measurement were 318(13.3%). 2. Researches using biological measurement in the Korean Academy of Nursing were highest(97papers, 17.5%) among the nursing journals. The proportion of papers using biological measurement to total number of papers was the highest in the Journal of Korean Biological Nursing Science as 77.3%(51papers). 3. The 233 papers(73.3%) were experimental researches among 318 papers using biological measurement which showed the highest proportion. 4. Patients were highest subjects of researches using biological measurement(197papers, 61.9%). 5. Blood test was most frequently used as physiological variables from 2001 to 2004. Conclusion: Researches using biological measurement of 10 Korean Nursing Journals in year 2000-year 2004 were very low. We need more researches using biological measurement to provide more objective evidence for nursing practice.

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Interpretation of Subsurface Fracture Characteristics by Fracture Mapping and Geophysical Loggings (단열조사 및 물리검층을 통한 지표 하 단열특성 해석)

  • Chae, Byung-Gon;Lee, Dae-Ha;Kim, Yu-Sung;Hwang, Se-Ho;Kee, Weon-Seo;Kim, Won-Young;Lee, Seung-Gu
    • Journal of the Korean GEO-environmental Society
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    • v.2 no.1
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    • pp.37-56
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    • 2001
  • As a preliminary study to establish fracture network model in crystalline rocks, detail investigation on fracture characteristics were performed. Five fracture sets were determined on the basis of regional survey of geological structures and fractures on outcrops. Among the fracture sets, S1 set has the highest density and longest trace length of fractures which was identified on surface in the study area. S4 and S5 sets are composed of foliations and foliation parallel shear joints of gneisses, which are very important sets at the aspect of weighting of fracture length. For characterization of subsurface fractures, detail core logging was performed to identify fractures and fracture zones from five boreholes. Acoustic televiewer logging and borehole geophysical loggings produced images, orientations and geophysical properties of fractures which intersect with boreholes. According to the result of the investigations, subsurface fractures can be grouped as three preferred orientations(B1, B2 and B3), which correspond to S1, S2 and S4/S5 of surface fracture sets, respectively. Actually, B1 set is expected to be intensely developed at subsurface. However, it has low frequency of intersection with boreholes due to its parallel or sub-parallel direction to boreholes. According to the inference of conductive fractures, B1 and B3 sets have possibilities of water flow and their intersection lines are also thought to consist of important conduits of groundwater flow. In particular, faults which are parallel to foliations control major groundwater flow in the study area.

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Data Replicas Relocation Strategy in Mobile Computing System Environment (이동 컴퓨팅 시스템 환경에서 데이터 복제 재배치 기법)

  • Choe, Gang-Hui;Jo, Tae-Nam
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.10
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    • pp.2587-2596
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    • 1999
  • Recently, by the extension of skills like LAN, the wireless telecommunication network and the satelite services make it possible for the mobile computer users to access a database. A method to use the replicated database on a server to get new data without missing any information has been being studied. So far we have used the Static Replica Allocation(SRA) for the replication which is the method of the replication on the server. This method is to replicate the data on the replica server after a moving host is transferred to a cell. Since the network of the SRA is very good, and if there are few moving users, no trouble will happen. But if there is no moving users in a cell, the data will not be shared. Therefore, this paper is about the study of the method of relocation after replicating the data to the cells for the users(User Select Replica Allocation : USRA). We also analyze the access rate and the possibility which are closely related to the moving frequency of the mobile hosts and the numbers of the cells. As a result, We show that the 120% lower access cost and the 40%∼50% gains are achieved from the low mobility

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Nutrients Intake and Dietary Quality of Korean Parkinson's Disease Patients According to the Duration of Disease (유병기간에 따른 한국인 파킨슨병 환자의 영양소 섭취 상태 및 식사의 질에 관한 연구)

  • Lee, Ju-Yeon;An, Tae-Beom;Jeon, Beom-Seok;Kim, Yun-Young;Choue, Ryo-Won
    • Korean Journal of Community Nutrition
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    • v.13 no.4
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    • pp.582-591
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    • 2008
  • Both genetic and environmental factors play important roles in the pathogenesis of Parkinson Disease(PD). The contribution of many environmental factors including dietary factor remains unproven. The purpose the study was to investigate the dietary habits, nutrient intake and dietary quality of Korean PD patients according to the duration of disease. PD patients were recruited from K and S university hospitals from May 2005 to January 2006. This study was carried out after approval by the Institute Review Board(IRB). British Brain Bank criteria was used to diagnose PD. The subjects were classified into 2 groups based on the duration of PD: <25 months and $\geq$25 months groups. General characteristics, anthropometric measurements, food habits and dietary intakes were investigated. The results of this study were as follows: 1) The mean age of <25 months group($66.9{\pm}8.0$ yr) was significantly higher than that of $\geq$25 months group($62.2{\pm}8.8$ yr)(p<0.05). No significant differences were found for academic background, occupation, living status and social activity, however, numbers of diseases, exercise and family history of PD were significantly different. 2) Anthropometric measurements were not different between the two groups. 3) The frequency of taking snacks was significantly higher in <25 months group and the amounts of alcohol consumption were significantly higher in $\geq$25 months group. 4) Daily intakes of most nutrients were very low compared with DRI. 5) The MAR score was significantly lower in <25 months group(p<0.05;) however, the scores of DVS, DDS and DQI were not significantly different. As a conclusion an overall nutrient intake and dietary quality of the Parkinson's Disease patients need to be improved regardless of duration of the disease and a well-balanced diet should be emphasized.

Visible Light Communication Based Wide Range Indoor Fine Particulate Matter Monitoring System (가시광통신 기반 광역 실내 초미세먼지 모니터링 시스템)

  • Shakil, Sejan Mohammad Abrar;An, Jinyoung;Han, Daehyun;Chung, Wan-Young
    • Journal of the Institute of Convergence Signal Processing
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    • v.20 no.1
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    • pp.16-23
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    • 2019
  • Fine particulate matter known as PM 2.5 refers to the atmospheric particulate matter that has a diameter less than 2.5 micrometer identified as dangerous element for human health and its concentration can provide us a clear picture about air dust concentration. Humans stay indoor almost 90% of their life time and also there is no official indoor dust concentration data, so our study is focused on measuring the indoor air quality. Indoor dust data monitoring is very important in hospital environments beside that other places can also be considered for monitoring like classrooms, cements factories, computer server rooms, petrochemical storage etc. In this paper, visible light communication system is proposed by Manchester encoding technique for electromagnetic interference (EMI)-free indoor dust monitoring. Important indoor environment information like dust concentration is transferred by visible light channel in wide range. An average voltage-tracking technique is utilized for robust light detection to eliminate ambient light and low-frequency noise. The incoming light is recognized by a photo diode and are simultaneously processed by a receiver micro-controller. We can monitor indoor air quality in real-time and can take necessary action according to the result.

A study on improving fairness and congestion control of DQDB using buffer threshold value (버퍼의 문턱치값을 이용한 DQDB망의 공평성 개선 및 혼잡 제어에 관한 연구)

  • 고성현;조진교
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.4
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    • pp.618-636
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    • 1997
  • DQDB(Distributed Queue Dual Bus) protocol, the IEEE 802.6 standard protocol for metropolitan area networks, does not fully take advantage of the capabilities of dual bus architecture. Although fairness in bandwidth distribution among nodes is improved when using so called the bandwidth balancing mechanism, the protocol requires a considerable amount of time to adjust to changes in the network load. Additionally, the bandwidth balancing mechanism leaves a portion of the available bandwidth unused. In a high-speed backbone network, each node may act as a bridge/ router which connects several LANs as well as hosts. However, Because the existence of high speed LANs becomes commonplace, the congestionmay occur on a node because of the limitation on access rate to the backbone network and on available buffer spaces. to release the congestion, it is desirable to install some congestion control algorithm in the node. In this paper, we propose an efficient congestion control mechanism and fair and waster-free MAC protocol for dual bus network. In this protocol, all the buffers in the network can be shared in such a way that the transmission rate of each node can be set proportional to its load. In other words, a heavily loaded node obtains a larger bandwidth to send the sements so tht the congestion can be avoided while the uncongested nodes slow down their transmission rate and store the incoming segments into thier buffers. this implies that the buffers on the network can be shared dynamically. Simulation results show that the proposed probotol significantly reduces the segment queueing delay of a heavily loaded node and segment loss rate when compared with original DQDB. And it enables an attractive high throughput in the backbone network. Because in the proposed protocol, each node does not send a requet by the segment but send a request one time in the meaning of having segments, the frequency of sending requests is very low in the proposed protocol. so the proposed protocol signigificantly reduces the segment queuing dely. and In the proposed protocol, each node uses bandwidth in proportion to its load. so In case of limitation of available buffer spaces, the proposed protocol reduces segment loss rate of a heavily loaded node. Bandwidth balancing DQDB requires the wastage of bandwidth to be fair bandwidth allocation. But the proposed DQDB MAC protocol enables fair bandwidth without wasting bandwidth by using bandwidth one after another among active nodes.

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Pd/Si-based Emitter Ohmic Contacts for AlGaAs/GaAs HBTs (AlGaAs/GaAs HBT 에미터 전극용 Pd/Si계 오믹 접촉)

  • 김일호
    • Journal of the Korean Vacuum Society
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    • v.12 no.4
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    • pp.218-227
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    • 2003
  • Pd/Si/Ti/Pt and Pd/Si/Pd/Ti/Au ohmic contacts to n-type InCaAs were investigated for applications to AlGaAs/GaAs HBT emitter ohmic contacts. In the Pd/Si/Ti/Pt ohmic contact, as-deposited contact showed non-ohmic behavior, and high specific contact resistivity of $5\times10^{-3}\Omega\textrm{cm}^2$ was achieved by rapid thermal annealing at $375^{\circ}C$/10 sec. However, the specific contact resistivity decreased remarkably to $2\times10^{-6}\Omega\textrm{cm}^2$ by annealing at $425^{\circ}C$/10sec. In the Pd/Si/Pd/Ti/Au ohmic contact, minimum specific contact resistivity of $3.9\times10^{-7}\Omega\textrm{cm}^2$ was achieved by annealing at $400^{\circ}C$/20sec. In both ohmic contacts, low contact resistivity and non-spiking planar interface between ohmic materials and InGaAs were maintained. Therefore, these thermally stable ohmic contact systems are promising candidates for compound semiconductor devices. RF performance of the AlGaAs/GaAs HBT was also examined by employing the Pd/Si/Ti/Pt and Pd/Si/Pd/Ti/Au systems as emitter ohmic contacts. Cutoff frequencies were 63.9 ㎓ and 74.4 ㎓, respectively, and maximum oscillation frequencies were 50.1 ㎓ and 52.5 ㎓, respectively. It shows very successful high frequency operations.

Strain-Relaxed SiGe Layer on Si Formed by PIII&D Technology

  • Han, Seung Hee;Kim, Kyunghun;Kim, Sung Min;Jang, Jinhyeok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.155.2-155.2
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    • 2013
  • Strain-relaxed SiGe layer on Si substrate has numerous potential applications for electronic and opto- electronic devices. SiGe layer must have a high degree of strain relaxation and a low dislocation density. Conventionally, strain-relaxed SiGe on Si has been manufactured using compositionally graded buffers, in which very thick SiGe buffers of several micrometers are grown on a Si substrate with Ge composition increasing from the Si substrate to the surface. In this study, a new plasma process, i.e., the combination of PIII&D and HiPIMS, was adopted to implant Ge ions into Si wafer for direct formation of SiGe layer on Si substrate. Due to the high peak power density applied the Ge sputtering target during HiPIMS operation, a large fraction of sputtered Ge atoms is ionized. If the negative high voltage pulse applied to the sample stage in PIII&D system is synchronized with the pulsed Ge plasma, the ion implantation of Ge ions can be successfully accomplished. The PIII&D system for Ge ion implantation on Si (100) substrate was equipped with 3'-magnetron sputtering guns with Ge and Si target, which were operated with a HiPIMS pulsed-DC power supply. The sample stage with Si substrate was pulse-biased using a separate hard-tube pulser. During the implantation operation, HiPIMS pulse and substrate's negative bias pulse were synchronized at the same frequency of 50 Hz. The pulse voltage applied to the Ge sputtering target was -1200 V and the pulse width was 80 usec. While operating the Ge sputtering gun in HiPIMS mode, a pulse bias of -50 kV was applied to the Si substrate. The pulse width was 50 usec with a 30 usec delay time with respect to the HiPIMS pulse. Ge ion implantation process was performed for 30 min. to achieve approximately 20 % of Ge concentration in Si substrate. Right after Ge ion implantation, ~50 nm thick Si capping layer was deposited to prevent oxidation during subsequent RTA process at $1000^{\circ}C$ in N2 environment. The Ge-implanted Si samples were analyzed using Auger electron spectroscopy, High-resolution X-ray diffractometer, Raman spectroscopy, and Transmission electron microscopy to investigate the depth distribution, the degree of strain relaxation, and the crystalline structure, respectively. The analysis results showed that a strain-relaxed SiGe layer of ~100 nm thickness could be effectively formed on Si substrate by direct Ge ion implantation using the newly-developed PIII&D process for non-gaseous elements.

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Research Performance Evaluation Based on Quantitative Information Analysis in the Field of Herbal Medicine for Dementia Treatment (계량정보분석 기반의 연구개발 성과분석 : 치매 치료용 천연약물 분야)

  • Jeon, Won-Kyung;Han, Chang-Hyun;Kang, Jong-Seok;Heo, Eun-Jung;Han, Joong-Su;Lee, Young-Joon
    • Journal of Oriental Neuropsychiatry
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    • v.22 no.3
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    • pp.101-113
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    • 2011
  • Objectives : Trend of R&D of herbal medicine for dementia treatment was examined based on the quantitative information analysis for establishing the national strategy of research on dementia treatment with oriental medicine. Methods : Definition was made to clarify the technology for development of herbal medicine for dementia treatment. Based on the initial keyword provided by experts in the field, queries were compounded to conduct search in the search engines of WoS and DWPI. The raw data (papers or patents) extracted from the initial search were examined by expert-review before objects of analysis were determined. Then, the accumulated data was analyzed in terms of year, country and organization, which led to examination of the trend of R&D. And the research performance evaluation for dementia treatment technologies was also made in terms of country, organization and researcher based on the forward citation analysis. The international cooperation intensity was examined on the basis of analysis of network by researcher before analysis results were put together to select lead researchers. Results : According to the quantitative information analysis of 1,330 articles that were selected as analysis objects, the number of papers on natural products research for dementia treatment has increased by around 4.6 times in recent five years. This indicates that the intensive studies have been underway recently. It was found to be the US that had the highest level in research filed of herbal medicine for dementia treatment and the highest capacity of international cooperation for that purpose. On the contrary, Korea had the share of papers at 5.1%, the number of countries in cooperation research at 8, and the article quality index at 0.40, showing that the qualitative level was insufficient, compared to the quantitative outcome. In particular, Korea was found to have no intensity of international cooperation among researchers. In case of patent, the results of information analysis of 305 patents selected as analysis objects demonstrated that China had the highest share while Korea had the very low frequency of patent application quantitatively. Conclusions : In this study, the research to develop herbal medicine for dementia treatment has recently drawn much attention that has spread around the globe. Therefore, these results suggest establishing the strategy to develop technology for dementia treatment with oriental medicine in the future based on quantitative information analysis.

Block Replacement Scheme based on Reuse Interval for Hybrid SSD System (Hybrid SSD 시스템을 위한 재사용 간격 기반 블록 교체 기법)

  • Yoo, Sanghyun;Kim, Kyung Tae;Youn, Hee Yong
    • Journal of Internet Computing and Services
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    • v.16 no.5
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    • pp.19-27
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    • 2015
  • Due to the advantages of fast read/write operation and low power consumption, SSD(Solid State Drive) is now widely adopted as storage device of smart phone, laptop computer, server, etc. However, the shortcomings of SSD such as limited number of write operations and asymmetric read/write operation lead to the problem of shortened life span of SSD. Therefore, the block replacement policy of SSD used as cache for HDD is very important. The existing solutions for improving the lifespan of SSD including the LARC scheme typically employ the LRU algorithm to manage the SSD blocks, which may increase the miss rate in SSD due to the replacement of frequently used block instead of rarely used block. In this paper we propose a novel block replacement scheme which considers the block reuse interval to effectively handle various data read/write patterns. The proposed scheme replaces the block in SSD based on the recency decided by reuse interval and age along with hit ratio. Computer simulation using workload trace files reveals that the proposed scheme consistently improves the performance and lifespan of SSD by increasing the hit ratio and decreasing the number of write operations compared to the existing schemes including LARC.