• Title/Summary/Keyword: external connection

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Feasibility of Optoelectronic Neural Stimulation Shown in Sciatic Nerve of Rats (흰쥐의 좌골 신경 자극을 통한 광전 자극의 가능성에 대한 연구)

  • Kim Eui tae;Oh Seung jae;Baac Hyoung won;Kim Sung june
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.611-615
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    • 2004
  • A neural prostheses can be designed to permit stimulation of specific sites in the nervous system to restore their functions, lost due to disease or trauma. This study focuses on the feasibility of optoelecronic stimulation into nervous system. Optoelectronic stimulation supplies, power and signal into the implanted optical detector inside the body by optics. It can be effective strategy especially on the retinal prosthesis, because it enables the non-invasive connection between the external source and internal detector through natural optical window 'eye'. Therefore, we designed an effective neural stimulating setup by optically based stimulation. Stimulating on the sciatic nerve of a rat with proper depth probe through optical stimulation needs higher ratio of current spreading through the neural surface, because of high impedance of neural interface. To increase the insertion current spreading into the neuron, we used a parallel low resistance compared to load resistance organic interface and calculated the optimized outer parallel resistance for maximum insertion current with the assumption of limited current by photodiode. Optimized outer parallel resistance was at a range of 500Ω-700Ω and a current was at a level between 580uA and 650uA. Stimulating current efficiency from initial photodiode induced current was between 47.5 and 59.7%. Various amplitude and frequency of the optical stimulation on the sciatic nerve showed the reliable visual tremble, and the action potential was also recorded near the stimulating area. These result demonstrate that optoelectronic stimulation with no bias can be applied to the retinal prosthesis and other neuroprosthetic area.

Review of the Structural Shape for Aft Transition Ring of Submarine (잠수함 함미 트랜지션 링 구조 형상에 대한 고찰)

  • Oh, Dohan;Ahn, Namhyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.7
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    • pp.936-944
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    • 2019
  • Submarines, which have been called an invisible force, are strategic underwater weapon systems that perform missions such as anti-surface warfare, anti-submarine warfare, and high payoff target strikes with the advantage of underwater covertness. A submarine should be able to withstand the hydrostatic pressure of the deep sea. In this respect, the submarine pressure hull, as the main structural system to resist the external pressure corresponding to the submerged depth, should ensure the survivability from hazards and threats such as leakage, fires, shock, explosion, etc. To do this, the initial scantling of the submarine pressure hull must be calculated appropriately in the concept design phase. The shape of the aft transition ring varies according to its connection with the submarine aft end conical structure, pressure hull cylindrical part, and non-pressure hull of the submarine; the design of the aft transition ring should not only take into account stress flow and connectivity but also the cost increase due to the increased man-hours of its complex geometry. Therefore, trade-off studies based on the four different shapes of the aft transition ring are carried out considering both the review of the structural strength through nonlinear finite element analysis (FEA) and economic feasibility by reviewing the estimations of the manufacturing working days and material costs. Finally, the most rational structural aft transition ring shape for a submarine amongst four reviewed types was proposed.

Experimental investigation on valve rattle noise of automotive electronic-wastegate turbochargers (차량용 전자식 웨이스트 게이트 터보차져의 밸브 떨림음에 대한 실험적 고찰)

  • Park, Hoil;Eom, Sangbong;Kim, Youngkang;Hwang, Junyoung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.10a
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    • pp.686-686
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    • 2013
  • Automotive turbochargers have become common in gasoline engines as well as diesel engines. They are excellent devices to effectively increase fuel efficiency and power of the engines, but they unfortunately cause several noise problems. The noises are classified into mechanical noises induced from movement of a rotating shaft and aerodynamic noises by air flow in turbochargers. In addition to, there is a mechanical noise caused from movement of an actuator, electronically controlling a wastegate valve. It is called as valve rattle noise. The actuator is connected to a valve through a linkage. The noise occurs only if the valve is open, where the linkage is freely contact to neighbor structures without being constrained by any external forces. This condition allows impacts by the pulsation of exhaust gas, and the vibration from the impacts spreads out through turbine housing, causing the rattle noise. The noise is not in mechanical operating wastegate turbochargers because the linkage of an actuator is strongly connected by actuating force. For the electronic wastegate turbocharger, this paper proposed a test device to show the noise generating mechanism with a small vibration motor having an unbalanced shaft. It also shows how to reduce the noise - reduction of linkage clearances, inserting wave washers into a connection, and applying loose fitting in bushing embracing a valve lever to turbine housing.

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Quality Improvement in Patient Care Services : Obstacles and Approaches (진료의 질관리에 대한 시론 -장애와 접근-)

  • 한달선
    • Health Policy and Management
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    • v.2 no.2
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    • pp.112-130
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    • 1992
  • Patient care services are provided to individual patients in response to their health needs produced by illnesses or injuries. The services are often addressed to very serious conditions, and also they constitute the most expensive component of health care services. Therefore, the importance of quality is emphasized, but there are many indications that patient care quality is far from a satisfactory state in most of the countries. Based upon this observation, it is attempted to examine obstacles and approaches to quality improvement in patient care services. In doing so, following Taguchi's(1986) definition of product quality, quality of patient care services is conceived of as better when the less is the sociental loss attributalbe to variability of intended function and harmful side effects they emhibit after being delivered. Some distinguishing features of medical care sector pose difficulties in implementing effective quality improvement programs in patient care services. Nevertheless, newly proposed method of quality management, based on industrial quality management approach, seems to have a great deal of potential to effectively cope with such difficulties. This method, unlike the traditional approach to quality assurance, focuses on total organisational processes, not individuals, as the obproach to quality assurance, focuses on total organizational processes, not individuals, as the objects of quality improvement; variation, not comparison with standards, in quality measurement; and continuous improvement, not removing only bad quality care, as an ideal. Prerequisite to a successful use of any quality mangement method is motivating providers to improve quality. Conceivable approaches for such motivation are self-regulation, external controls and promotion of competition. Since these approaches are not mutually exclusive, they may be employed in an appropriate combination. In Korea, medical care providers are now functioning under the circumstances where they have little reason for making efforts to improve quality of their services. Once these circumstantial conditions are changed to exert pressures on providers to improve quality, the use of adequate quality management method becomes an issue. In this connection, much attention shoould be directed to the newly proposed method described above. In all these efforts for improving quality of patient care services, health insurance would be able to play a pivotal role. Poviders of medical care, buth indiciduals and organizations, are usually very responsive to the measures that affect their financing, and thus health insurance can be a strong instrument for motivationg providers to improve quality. Also, the insurance continuously acquires data on patient care, which could be processed to produce information required to effective quality control.

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Efficient 3D Object Simplification Algorithm Using 2D Planar Sampling and Wavelet Transform (2D 평면 표본화와 웨이브릿 변환을 이용한 효율적인 3차원 객체 간소화 알고리즘)

  • 장명호;이행석;한규필;박양우
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.5_6
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    • pp.297-304
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    • 2004
  • In this paper, a mesh simplification algorithm based on wavelet transform and 2D planar sampling is proposed for efficient handling of 3D objects in computer applications. Since 3D vertices are directly transformed with wavelets in conventional mesh compression and simplification algorithms, it is difficult to solve tiling optimization problems which reconnect vertices into faces in the synthesis stage highly demanding vertex connectivities. However, a 3D mesh is sampled onto 2D planes and 2D polygons on the planes are independently simplified in the proposed algorithm. Accordingly, the transform of 2D polygons is very tractable and their connection information Is replaced with a sequence of vertices. The vertex sequence of the 2D polygons on each plane is analyzed with wavelets and the transformed data are simplified by removing small wavelet coefficients which are not dominant in the subjective quality of its shape. Therefore, the proposed algorithm is able to change the mesh level-of-detail simply by controlling the distance of 2D sampling planes and the selective removal of wavelet coefficients. Experimental results show that the proposed algorithm is a simple and efficient simplification technique with less external distortion.

A Study on Coherence in the Structure of IB DP Mathematics Curriculum Documents (IB DP 수학과 교육과정 문서 체재의 일관성 분석 연구)

  • Oh, Kukhwan;Lee, Changsuk;Lee, Kyungwon;Kwon, Oh Nam
    • Communications of Mathematical Education
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    • v.35 no.1
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    • pp.75-96
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    • 2021
  • This study aims to drive the implications for the structure of mathematics curriculum documents in Korea, exploring the coherence in the documental structure of the IB DP mathematics curriculum, which is gaining international attention. The documents of the IB DP mathematics curriculum were analyzed based on the coherence of external and internal structures. First, the curriculum was consistently described by subject and topic, presenting the table of contents and structure of the documents in the same format. Second, the descriptions of the curriculum between subjects and within the subjects were consistent through the same composition of the subject and assessment methods, the presentation of big ideas, and 'Guidance, clarification and syllabus links'. Third, in 'Connections', the curriculum documents were described with coherence through linking with other subjects by describing the connection plan with the real-world contexts, other subjects, and the 'Theory of Knowledge' in the IB curriculum. Based on these findings and implications for the concreteness and consistency of the components in mathematics curriculum documents, we propose the coherence between the presentation of subject areas and assessment methods of the revised curriculum, and the implementation of coherence in documental structure through links with other subjects.

Paradox of Meritocracy of the Social Welfare Organization in the Neoliberalism (사회복지 실천현장의 신자유주의적 성과주의 역설: 사회복지사의 경험을 중심으로)

  • Lee, In Sook
    • 한국사회정책
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    • v.24 no.1
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    • pp.239-275
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    • 2017
  • The purpose of this study is to explore what social workers experience and how they experience the needs of Meritocracy in the social welfare organization in the neoliberalism.. Therefore, in-depth interviews were conducted with 18 social workers, and I analyzed Colaizzi(1978) in a phenomenological method through collected research materials. As a result, the analysis is integrated in a total of four essential themes. According to the research results, the meritocracy - oriented phenomenon in the social welfare organization was 'paradox of Meritocracy'. Participants were buried in creating "nominal performance without any effectiveness" based on effectiveness and efficiency. Clients were instrumentalized in performance; moreover, they lost contact points with the field. Above all, there was "a reorganization of practices" that contradicted the original values of practice, in which the quality deterioration of service and the connection between organizations were weakened. In addition, the implementation of accountability of social welfare organization, which was intended by Meritocracy, has become a criterion for external evaluation, and the challenge of uncertain result has left a "rigid accountability without discretion." While participants were devoted to making a nominal performance, they failed to be guaranteed by the distinct characteristics of social welfare group. They experienced lost pride of the practitioner in the reality which contained the value of social welfare. However, in spite of this paradox of Meritocracy, participants demonstrated flexibility in order to preserve the original value and reached "a compromise with reality in the identity conflict." Based on the results of the research, I presented the discussion and policy directions.

A study on the degree of aging recognition of firefighters and countermeasures(focus on firefighters in Jeollanam-do) (소방공무원의 고령화 인식정도와 대응방안에 관한 연구(전라남도 소방공무원을 중심으로))

  • Ha, Kang Hun;Kim, Jae Ho;Choi, Jae Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.398-407
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    • 2021
  • Firefighters (who are responsible for people's safety) have one of the jobs that are expected to have problems due to aging in the workforce. An increase in the average age of firefighters can lead to serious social problems. The aim of this study is to survey firefighters in Jeollanam-do about their awareness of aging in firefighters, and to propose a plan to prepare them for aging through investigation and analysis of work problems that may occur due to an aging workforce. The survey shows that the higher the age group, the higher the awareness of aging firefighters, and the higher the total work experience and internal/external work experience, the higher the awareness of aging. As a plan to solve various problems that may arise from aging in firefighters, regular operation of physical fitness promotion programs, field work, job rotation, and managerial measures (such as a change of position to an administrative department) are prepared, and drone or robot technology is used. These solutions include the introduction of applied high-tech technologies to firefighting activities, establishment of retirement management policies, and preparation of plans to revitalize the connection to private employment. In order to maximize the applicability of the field, government institutional plans and preparations are essential.

Development of IFC Standard for Securing Interoperability of BIM Data for Port Facilities (항만 BIM 데이터의 상호운용성 확보를 위한 IFC 표준 개발)

  • Moon, Hyoun-Seok;Won, Ji-Sun;Shin, Jae-Young
    • Journal of KIBIM
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    • v.10 no.1
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    • pp.9-22
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    • 2020
  • Recently, BIM has been extended to infrastructures such as roads and bridges, and the demand for BIM standard development for ports is increasing internationally. Due to the low level of utilization of classification system and drawing standards compared to other infrastructures, and the closed nature of national security facilities, ports have insufficient level of connection and sharing environment among external systems or users. In addition, since the standardization of data for port facilities is not made, it is still necessary to establish an independent DB for each system and to ensure interoperability of data between these systems since it does not have a shared environment among similar data. Therefore, the purpose of this study is to develop and verify IFC, the international standard for BIM, in order to cope with the BIM environment and to be commonly used in the design, construction, and maintenance of port facilities. To this end, we build a standard schema with port-specific Express Notation according to buildingSMART International's standard development methodology. First, domestic and international reference model standards were analyzed to derive components such as space and facilities of port facilities. Based on this, the components of the port facility were derived through the codification, categorization, and normalization process developed by the research team. This was extended based on the port BIM object classification system developed by the research team. Normalization results were verified by designers and associations. Then, IFC schema construction was based on Express-G data modeling based on IFC 4 * 2 Candidate, which is a bridge candidate standard based on IFC4 (ISO16739), and IFC 4 * 3 Draft, which is developed by buildingSMART International. The final schema was validated using the commercialized validation tool. In addition, in order to verify the structural verification of the port IFC schema, the transformation process was verified by converting the caisson model into a Part21 file. In the future, this result will not only be used as a delivery standard for port BIM products, but will also be applied as a linkage standard between systems and a common data format for port BIM platforms when BIM is used in the maintenance phase. In particular, it is expected to be used as a core standard for data exchange in the port maintenance stage.

Systematic Review in Regard to Career Education for Students Who Major in Physical Education (체육전공 대학생의 진로 교육 방안에 관한 체계적 문헌고찰)

  • Lee, Weon-Il;Lee, Eun-Young;Yi, KyoungJune;Jin, Yeon Kyung
    • 한국체육학회지인문사회과학편
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    • v.58 no.3
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    • pp.241-260
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    • 2019
  • The purpose of this study is to explore effective and practical career plans reflecting demand of the field, in regard to education for university students who major in physical education, as the importance and necessity of career education at a university level are increasing. Systematic literature review (PRISMA) methodology was used for this study. From 38 pieces of literature that were finally selected for this study, research results were put together from three perspectives as follows: 1. 'Factors Related to Students' Decision-Making for Career' which should be considered in career education for physical education majors; 2. Problems of Career Education in the Physical Education Curriculum, and; 3. Improvement Plans. First, it was found that students' decision-making for career is affected by individuals' personal internal factors (i.e., satisfaction with major, self-efficacy, and career barrier) and external factors (i.e., counselling history on career paths, career conditions, and the status of related jobs). Second, the state of career education for physical education majors was found to be insufficient in terms of a lack of career education in the curriculum, a lack of support from major professors, and a lack of support for field experience. Third, improvement plans were suggested from the following perspectives: development of systematic career education curriculum (i.e., fostering leadership, reorganization of curriculum focused on career specialty, and operation of systematic curriculum); provision of an adequate environment for career education (i.e., establishment of infrastructure that links the university to society and collection of information on career paths for physical education majors). Moreover, the necessity to develop career education curriculum in connection with demand of students regarding career, the lack of systematic information on career paths of physical education majors, and the lack of researches on career education for physical education majors were discussed in this study.