• Title/Summary/Keyword: D2D systems

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Analysis and Design of Soft Ground Tunnels Subject to Steady-State Groundwater Flow (정상류 조건하의 토사터널의 해석 및 설계)

  • Lee, In-Mo;Nam, Seok-Woo;Lee, Myung-Jae
    • Geotechnical Engineering
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    • v.10 no.2
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    • pp.41-56
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    • 1994
  • Under the groundwater level, the tunnel face is affected by the seepage force and the groundwater flow may cause a trouble to the tunnel support systems. The appropriate methods of analysis and design in the tunnel face and the lining, considering groundwater flow according to tunnel drainage condition are presented in this thesis. First, the effect of seepage on the stability of tunnel face was studied. Seepage force was estimated by the 3-D finite element analysis and the stability of tunnel face was checked by analytical method. Furthermore, using the finite difference method the stress and displacement on the face were computed for either case, where the seepage force is or is not considered, and the effect of seepage on the tunnel face stability was evaluated. Second, the effect of seepage force on the tunnel lining when construction is finished and steady state seepage flow occurs was studied and a design methodology considering seepage effect was made. Consequently, in case where the groundwater level remains almost unchanged and the steady state groundwater flow occurs, the proper countermeasures for face staility are required according to the condition of groundwater flow. Moreover, the tunnel lining should be designed and constructed considering the seepage force occuring by the groundwater flow toward the tunnel linings.

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A Study on the Verification of Design Compatibility for a Europe Type Automatic Coupler Head according to TSI Certification Standards (TSI 인증기준에 따른 유럽 표준형 자동복합연결기 헤드의 설계적합성 검증 연구)

  • Min, Kyeong Bin;Park, Jin Kyu;Kang, Ji Sung;Kim, Ki Nam
    • Journal of the Korean Society for Railway
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    • v.19 no.1
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    • pp.29-37
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    • 2016
  • The type approval system of the railway safety law, which was enforced in 2014, has been preferentially applied to the field of railway vehicles. The type approval system addresses railway vehicles and railway constituents. Unlike the previous system, it requires serial verification stages divided, in consecutive order, into verification of design compatibility and conformity and type test. These stages are in accord with international certification systems including TSI certification of the European commission. This study has been carried out to find and meet the design requirements for a coupler head, which is a part of the automatic coupler system; requirements were drawn from TSI and technical specifications that are subordinate to the domestic railway approval system. Through this study, it has been found that there exist 34 design requirements to acquire a complete coupler head. Among those requirements, 32 were verified by document inspection and two were able to be verified by performing FEA and gathering range analysis data.

Implementation of Greenhouse Environmental Control Systems using Intelligence (지능을 이용한 온실 제어 시스템)

  • Yang, J.;Chung, C.D.;Hong, You-Sik;Ahn, B.I;Hwang, S.I.;Choi, Y.H.
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.49 no.2
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    • pp.29-37
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    • 2012
  • An experiment for an optimized automatic greenhouse environment in a flower farming greenhouse by building a ubiquitous sensor network with various sensors was conducted and the results were evaluated. And various culturing environmental information and data in the greenhouse were collected and analyzed. Then, the greenhouse was designed to maintain the best culturing environment on the basis of existing recommended optimized figures. By measuring the growth of the crops in the greenhouse, A system which controls facilities in the greenhouse to maintain the best culturing environment in accordance with change in the environment was analyzed.Computer simulation result proced that we discovered that controlling the facilities and the artificial light source increased production, enhanced quality, reduced labor and heating cost immensely. The experiment has proved that the u-flower farming system can maximize the income of farm families by sending warning messages to users of this system when weather suddenly changes so that users may cope with such changes and maintain the best culturing environment.

A Comparison of the Shoulder Stabilizer Muscle Activities During Push-up Plus Between Persons With and Without Winging Scapular (푸시업플러스(Push-up plus) 운동 시 견갑골 익상 유무에 따른 어깨안정근의 근활성도 비교)

  • Park, Jun-Sang;Jeon, Hye-Seon;Kwon, Oh-Yun
    • Physical Therapy Korea
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    • v.14 no.2
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    • pp.44-52
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    • 2007
  • This study was carried out to compare the muscle activities of the shoulder stabilizers between persons with and without winging scapular during push-up plus exercise (adds the scapular protraction to the general push-up exercise). For this study, eleven males with winging scapular and eleven healthy males were recruited. Surface electromyographic (EMG) activity was recorded from the serratus anterior, upper trapezius, lower trapezius, infraspinatus, and pectoralis major while the subjects performed the push-up plus. Each push-up plus was subdivided into three phases according to the elbow position which was measured using the 3-D motion analysis system: elbow flexion (EF), elbow extension (EE), and shoulder protraction phases (SP). Two-way repeated measure ANOVA (phase ${\times}$ group) were used for statistical analysis. There was significant phase by group interaction only on the EMG composition ratio of the serratus anterior (p>.05). The EMG composition ratio of the serratus anterior was significantly higher in SP than in either EF or EE however, it was not different between winging scapular and normal groups. For both groups, the EMG composition ratio of upper trapezius, lower trapezius, and pectoralis major was significantly different across the phases of push-up plus, but the infraspinatus EMG composition ratio was not. For both groups, in EF and EE phases, the EMG composition ratio of both pectoralis major and serratus anterior were relatively higher than that of other muscles. However, in both groups, the EMG composition ratio of the serratus anterior became much more predominant than that of the pectoralis major. In addition, infraspinatus activated greater than pectoralis major. These results showed that the push-up plus exercise is effective to selectively strengthen the serratus anterior for both individuals with and without winging scapular, but not equally effective for other shoulder stabilizers.

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Diagnosis of Performance Degradation of Direct Methanol Fuel Cell Stack after Long-Term Operation (장기운전에 의한 직접메탄올 연료전지 스택의 성능 열화 분석)

  • Kim, Sang-Kyung;Hyun, Min-Soo;Lee, Byung-Rok;Jung, Doo-Hwan;Peck, Dong-Hyun;Lim, Seong-Yop
    • Korean Chemical Engineering Research
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    • v.49 no.6
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    • pp.775-780
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    • 2011
  • 5-cell DMFC stack was fabricated and operated with the load of 4 A for 4000 hrs. After 4000 hrs operation peak power density of the stack reduced by 27.3%. Two of the five cells did now show performance degradation, the performance of other two was reduced by 40% and the performance of the other decreased by 60%. The amount of performance degradation of each cell by long-term operation did not correlate with the position in the stack. Platinum particle size in the anode catalyst layer of the MEA with the strongest degradation increased and the increase was severer on the position of methanol inlet than on the position of methanol outlet. However, platinum particle size in the cathode catalyst layers did not changed for all the MEA'. Ruthenium crossover from the anode catalyst layer to the cathode catalyst layer through the membrane was observed after 4,000 hrs operation by SEM-EDX and it occurred for all MEA' regardless of the degree of performance degradation. Atomic ratio of ruthenium to platinum in the cathode catalyst layer was the highest in the MEA with the strongest performance degradation.

The Present Situation and Tasks of University Nursing Education in Korea (한국 간호교육의 현황과 과제)

  • Kim, Yoon-Hee;Kim, Kwang-Joo;Cho, Kyoul-Ja
    • Journal of East-West Nursing Research
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    • v.5 no.1
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    • pp.120-126
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    • 2000
  • This study was intended to grasp the history of nursing education from the beginning to the present in Korea, and grip and look-out current diversified systems of nursing education on basis of February, 2000 through literatural review and investigation by close telephone interviews. The basic nursing educational institutions in the whole country were total 113, namely, 3 years course, 65 junior colleges of nursing, and 4 years course, 48 colleges of nursing. And there were 3 types of continuing nursing educational system: two of three were transferring to another college for gain bachelor's degree in nursing; RN-BSN programs and university of broadcasting, and the other was the system of independent learning and then examination for BSN. Total nursing graduates from junior college of nursing courses and college of nursing courses were 7,564 on February, 1999. In general graduate school, the number of master courses were 21 and Ph.D courses were 13. And the number of special graduate schools were 21, i.e., graduate school of education were 7, graduate school of administration were 2, graduate school of public health were 11 and graduate school of industry was 1. As the perspective on nursing education, we overviewed changing nursing organizational environment, increasing the system of continuing education, making standards in nursing education and systemization of nursing educational accreditation, specialization of nursing, information system in nursing education and education of graduate school. The summary of the above overviewed subjects were as follows; Every nursing educational institution needed to educate by educational criteria and standard and characteristically run BSN and graduate courses. Specialization in nursing has to develop more and more, therefore advanced education and law should be prepared appropriately. According to the age's and social needs, we have to establish counter-plan for fundamental educational environment. We have to sensitive to rapidly changing information in the era of globalization. In the level of university education, each university needs characterization of educational objectives, goals and contents, and has to replace the shortage of the number of professor. And the regulation of thesis and dissertation examinations need to be reinforced. Education in nursing should consists with specialization. Collaboration among universities will bring efficiency in the nursing education.

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Intelligent Diagnosis Assistant System of Capsule Endoscopy Video Through Analysis of Video Frames (영상 프레임 분석을 통한 대용량 캡슐내시경 영상의 지능형 판독보조 시스템)

  • Lee, H.G.;Choi, H.K.;Lee, D.H.;Lee, S.C.
    • Journal of Intelligence and Information Systems
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    • v.15 no.2
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    • pp.33-48
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    • 2009
  • Capsule endoscopy is one of the most remarkable inventions in last ten years. Causing less pain for patients, diagnosis for entire digestive system has been considered as a most convenience method over a normal endoscope. However, it is known that the diagnosis process typically requires very long inspection time for clinical experts because of considerably many duplicate images of same areas in human digestive system due to uncontrollable movement of a capsule endoscope. In this paper, we propose a method for clinical diagnosticians to get highly valuable information from capsule-endoscopy video. Our software system consists of three global maps, such as movement map, characteristic map, and brightness map, in temporal domain for entire sequence of the input video. The movement map can be used for effectively removing duplicated adjacent images. The characteristic and brightness maps provide frame content analyses that can be quickly used for segmenting regions or locating some features(such as blood) in the stream. Our experiments show the results of four patients having different health conditions. The result maps clearly capture the movements and characteristics from the image frames. Our method may help the diagnosticians quickly search the locations of lesion, bleeding, or some other interesting areas.

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Comparison of the Priority of Required Capabilities of the Warrior Platform by the Types of Military Unit through AHP Analysis (AHP 분석을 통한 부대 임무유형별 워리어플랫폼 요구능력 우선순위 비교)

  • Kim, Wukki;Shin, Kyuyong;Jo, Seongsik;Baek, Seungho;Kim, Yongchul
    • Journal of Convergence for Information Technology
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    • v.11 no.6
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    • pp.262-269
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    • 2021
  • The Ministry of National Defense is re-establishing the role of the Army in accordance with the defense reform and is promoting the Warrior Platform, a next-generation individual combat system. The Warrior Platform project is divided into three stages and is being promoted. In the first stage, the quality and performance of individual items are improved, in the second stage, items between system development are integrated, and in the third stage, the combat capability is maximized by developing an integrated unit weapon system. In this paper, detailed sub-items for the five essential required competencies (survival, lethality, mobility, sustainability, Communication) that are considered for building an effective warrior platform are presented. We also present a plan that can be used to prepare a specific master plan for the Army's Warrior Platform project by using Analytic Hierarchy Process(AHP) and selecting the priority of the five required capabilities and detailed sub-items for different unit types. As a result of analyzing the priorities of the four types of units with different mission types, we find that there are differences for each unit. These results are expected to be used as useful reference materials for setting the future direction for the development of warrior platform.

Influence of Bacterial Attachment on Arsenic Bioleaching from Mine Tailings: Dependency on the Ratio of Bacteria-Solid Substrate (광물찌꺼기 내 비소의 미생물 침출 시 박테리아 흡착 영향: 박테리아와 고체 기질 비율에 관한 연구)

  • Park, Jeonghyun;Silva, Rene A.;Choi, Sowon;Ilyas, Sadia;Kim, Hyunjung
    • Resources Recycling
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    • v.30 no.3
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    • pp.30-40
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    • 2021
  • The present study investigates the bioleaching efficiencies of arsenic via contact and non-contact mechanisms. The attachment of Acidithiobacillus ferrooxidans was restricted by a partition system comprising a semi-permeable membrane with a molecular weight cutoff of 12-14 kDa. The results were compared for two arsenic concentrations in the system (1.0% and 0.5% w/v) to maintain a homogeneous system. The overall bacterial performance was monitored by comparing total arsenic and iron concentrations, Fe ion speciation, pH, and solution redox potentials in flask bioleaching experiments over a period of 10 d. Our results indicated that bacterial attachment could increase arsenic extraction efficiency from 20.0% to 44.9% at 1.0 % solid concentrations. These findings suggest that the bacterial contact mechanism greatly influences arsenic bioleaching from mine tailings. Therefore, systems involving two-step or non-contact bioleaching are less effective than those involving one-step or contact bioleaching for the efficient extraction of arsenic from mine tailings.

Analysis of virulence traits of Staphylococcus aureus isolated from bovine mastitis in semi-intensive and family dairy farms

  • Guzman-Rodriguez, Jaquelina J.;Leon-Galvan, Ma. Fabiola;Barboza-Corona, Jose E.;Valencia-Posadas, Mauricio;Loeza-Lara, Pedro D.;Sanchez-Ceja, Monica;Ochoa-Zarzosa, Alejandra;Lopez-Meza, Joel E.;Gutierrez-Chavez, Abner J.
    • Journal of Veterinary Science
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    • v.21 no.5
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    • pp.77.1-77.14
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    • 2020
  • Background: Staphylococcus aureus is one of the main microorganisms that causes bovine mastitis, and its well-known virulence characteristics and interactions with the environment are used to aid the design of more efficient therapies. Objectives: To determine whether the virulence traits, such as antibiotic resistance and biofilm-forming and internalization abilities, of S. aureus isolated from bovine mastitis are related to dairy production system types. Methods: The study was performed in the Mexican states of Guanajuato and Michoacan. Semi-intensive dairy farms (SIDFs) and family dairy farms (FDFs) (454 and 363 cows, respectively) were included. The 194 milk samples from mastitis affected quarters were collected and 92 strains of S. aureus were isolated and identified by biochemical and molecular tests. Antibiotic resistance, biofilm and internalization assays were performed on 30 randomly selected isolated strains to determine virulence traits, and these strains were equally allocated to the 2 dairy production systems. Results: All 30 selected strains displayed a high degree of resistance (50%-91.7%) to the antibiotics tested, but no significant difference was found between SIDF and FDF isolates. S. aureus strains from SIDFs had an average biofilm forming capacity of up to 36% (18.9%-53.1%), while S. aureus strains from FDFs registered an average of up to 53% (31.5%-77.8%) (p > 0.05). Internalization assays revealed a higher frequency of internalization capacity for strains isolated from FDFs (33.3%) than for those isolated from SIDFs (6.7%) (p > 0.05). fnbpA gen was detected in 46.6% of FDF strains and 33.3% of SIDF strains, and this difference was significant (p < 0.05). Conclusions: Our findings show that the virulence traits of S. aureus isolates analyzed in this study, depend significantly on several factors, such as phenotype, genotype, and environmental conditions, which are significantly related to dairy production system type and daily management practices.