• Title/Summary/Keyword: Development axis

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A Study of Evaluation Indices for Selecting Castle Remains Maintenance and Restoration Sections (성곽유적의 정비복원(整備復元) 대상구간 선정을 위한 평가지표 연구)

  • Kim, Hong-Gon;Choi, Key-Soo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.1
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    • pp.1-13
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    • 2012
  • Most of all Castle Remains in Korea were built on an axis of development with a scale of great magnitude. Because of its characteristics, the restoration and conservation plans should be phased in over medium and long term. There is no standards for evaluating the value of Castle Remains to set up the restoration and conservation sections. Some plans were set up through the value evaluation of its Castle Remains but those plans didn't have Evaluation System and different weight depending on different environment between Sanseong(mountain fortress) and Eupsung(fortress built in villages). To solve the limitation of Evaluation System of Castle Remains, this study try to approach in the Evaluation System methodology for selecting restoration sections. The results of its study follow below. First, this study drew the Evaluation Indices for selecting restoration sections of Castle Remains. There are three kinds of Elements(upper Index) and nine kinds of Evaluations(low Index). Second, Calculation of weight index by index on the questionnaire survey from expers through the relative importance analysis of AHP. Third, This study suggests the specific Evaluation System according to types; Sanseong(mountain fortress) and Eupsung(fortress built in villages);. Therefore, this study suggests standards to select the priority list for the restoration and conservation plan process and it can be used one of important standards in future plans.

Development of Fiber-end-cap Fabrication Equipment (대구경 광섬유 엔드캡 제작장비 개발)

  • Lee, Sung Hun;Hwang, Soon Hwi;Kim, Tae Kyun;Yang, Whan Seok;Yoon, Yeong Gap;Kim, Seon Ju
    • Korean Journal of Optics and Photonics
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    • v.32 no.2
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    • pp.49-54
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    • 2021
  • In this paper, we design and construct the equipment to manufacture large-diameter optical fiber end caps, which are the core parts of high-power fiber lasers, and we fabricate large-diameter optical fiber end caps using the home-made equipment. This equipment consists of a CO2 laser as a fusion-splice heat source, a precision stage assembly for transferring the position of a large-diameter optical fiber and an end cap, and a vision system used for alignment when the fusion splice is interlocked with the stage assembly. The output of the laser source is interlocked with the stage assembly to control the output, and the equipment is manufactured to align the polarization axis of the large-diameter polarization-maintaining optical fiber with the vision system. Optical fiber end caps were manufactured by laser fusion splicing of a large-diameter polarization-maintaining optical fiber with a clad diameter of 400 ㎛ and an end cap of 10×5×2 ㎣ (W×D×H) using home-made equipment. Signal-light insertion loss, polarization extinction ratio, and beam quality M2 of the fabricated large-diameter optical fiber end caps were measured to be 0.6%, 16.7 dB, and 1.21, respectively.

International Research Status on Spent Nuclear Fuel Structural Integrity Tests Considering Vibration and Shock Loads Under Normal Conditions of Transport (정상운반조건의 진동 및 충격하중을 고려한 사용후핵연료의 구조적 건전성 시험평가 해외연구현황)

  • Lim, JaeHoon;Cho, Sang Soon;Choi, Woo-seok
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.2
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    • pp.167-181
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    • 2019
  • Currently, the development of evaluation technology for vibration and shock load characteristics and spent nuclear fuel structural integrity under normal conditions of transport is being conducted in the Republic of Korea. This is the first such research conducted in the Republic of Korea and, thus, previous international studies need to be investigated and will be referred to in the ongoing project. Before 2000, several studies related to measurement of vibration and shock loads on spent nuclear fuel were conducted in the US. US national research institutes conducted uniaxial fuel assembly shaker tests, concrete block tests, and multi-axis fuel assembly tests between 2009 and 2016. In 2017, multi-modal transportation tests including road, sea, and rail transport were also performed by research institutes from the US, Spain and the Republic of Korea. Therefore, test preparation procedures, acceleration and strain measurement results, and finite-element and multi-body dynamics analysis were investigated. Based on the measured strain data, the preliminary conclusion was obtained that the measured strain was too small to cause damage to spent nuclear fuel rods. However, this conclusion is a preliminary conclusion that only reviews part of the results; a detailed review is being conducted in the US. The investigation of international studies on spent nuclear fuel structural integrity tests considering vibration and shock loads under normal conditions of transport in the US will be useful data for the project being conducted in the Republic of Korea.

Application of 3D printer in dental clinic (치과 진료실에서 3D 프린트의 활용)

  • Kim, Hyun Dong
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.27 no.2
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    • pp.82-96
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    • 2018
  • 3D printing is a process of producing 3d object from a digital file in STL format by joining, bonding, sintering or polymerizing small volume elements by layer. The various type of 3d printing is classified according to the additive manufacturing strategies. Among the types of 3D printer, SLA(StereoLithography Apparatus) and DLP(Digital Light Processing) 3D printer which use polymerization by light source are widely used in dental office. In the previous study, a full-arch scale 3d printed model is less precise than a conventional stone model. However, in scale of quadrant arch, a 3d printed model is significantly precise than a five-axis milled model. Using $3^{rd}$ Party dental CAD program, full denture, provisional crowns and diagnostic wax-up model are fabricated by 3d printer in dental office. In Orthodontics, based on virtual setup model, indirect bracket bonding tray can be generated by 3d printer. And thermoforming clear aligner can be fabricated on the 3d printed model. 3D printed individual drilling guide enable the clinician to place the dental implant on the proper position. The development of layer additive technology enhance the quality of 3d printing object and shorten the operating time of 3D printing. In the near future, traditional dental laboratory process such as casting, denture curing will be replaced by digital 3D printing.

Development and Validation of a Questionnaire on the Feasibility of a Mobile Dietary Self-Monitoring Application (식습관 관리 애플리케이션의 적용 가능성에 대한 설문지 개발 및 타당성 연구)

  • Lee, Heejin;Ahn, Jeong Sun;Lee, Jung Eun
    • Korean Journal of Community Nutrition
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    • v.27 no.2
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    • pp.146-157
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    • 2022
  • Objectives: This study aimed to develop and assess the content validity and internal consistency of a questionnaire on the feasibility of mobile dietary self-monitoring applications. Methods: We developed a feasibility questionnaire to assess the overall usage, convenience, usefulness, and satisfaction of mobile dietary applications. The initial draft of the questionnaire contained 17 items with yes/no, multiple-choice, and open-ended questions and 52 items on 5-point Likert scales. To validate the content, ten experts evaluated the relevance of the items for each subscale using a 5-point scale. We calculated the item-level content validity index (I-CVI) and scale-level content validity index (S-CVI). A total of 102 adults answered the questionnaires which reflected the experts' reviews. We conducted an exploratory factor analysis to determine the underlying structure of responses and categorized convenience, usefulness, and satisfaction. We also calculated Cronbach's alpha coefficient to examine the internal consistency of items in each subscale. Results: The S-CVI score of the items was 0.86, and we removed items with an I-CVI score of < 0.80. We combined, revised, or separated some remaining items and added one item as per the experts' comments. As a result, we included 16 items about overall usage and 42 sub-questions. Based on the responses of the 102 adults, we performed exploratory factor analysis using the principal axis method. We retained items with a factor loading of > 0.40, resulting in a final set of 35 questions (convenience: 15, usefulness: 12, satisfaction: 8 items). The Cronbach's alpha values of the three scales were 0.93, 0.91, and 0.91 for 1) usefulness, 2) convenience, and 3) satisfaction, respectively. Conclusions: We developed a feasibility questionnaire for mobile dietary self-monitoring applications and examined its content validity and internal consistency. Our questionnaire has the potential to measure the feasibility of mobile dietary self-monitoring applications.

Stiffness Improvement of Timing Belt in Power Transmission (동력전달용 타이밍벨트의 강성 개선)

  • Lee, Kyeong-Yeon;Byun, Kyung-Seok
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.1
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    • pp.1-7
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    • 2022
  • As a power transmission element, the timing belt is a toothed transmission belt that takes advantages of V-belts and gears. It has characteristics of non-slip and low noise. It is used as a power transmission device when transmitting power from a rotating shaft or linear motion in a mechanism. Rotation can be accurately transmitted through a belt pulley with grooves like a gear and a timing belt with grooves to precisely match with the belt pulley. In particular, in the mechanism in which the timing belt is used for the output shaft, the dynamic characteristics including the rigidity of the timing belt determine the transmission characteristics of the system, so its importance increases. In this paper, a stiffness reinforced belt that can be applied to a timing belt with a limited range of motion to increase its stiffness is proposed. To study the dynamic characteristics of the stiffness reinforced belt, the equation of motion for the stiffness reinforced belt was established, and a simulation model for the stiffness reinforced belt was created and analyzed. In order to confirm the analysis results of the motion equation and simulation model, a 1-axis rotation experimental equipment using a stiffness reinforcing belt was developed and the experiment was conducted. Through motion equations, simulation models, and experiment results, it was confirmed that the stiffness and dynamic characteristics of the timing belt could be improved by applying the proposed stiffness reinforcement belt.

Change in the Alignment and Distal Junctional Kyphosis Development after Posterior Cervical Spinal Fusion Surgery for Cervical Spondylotic Myelopathy - Risk Factor Analysis

  • Lee, Jung Jae;Park, Jin Hoon;Oh, Young Gyu;Shin, Hong Kyung;Park, Byong Gon
    • Journal of Korean Neurosurgical Society
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    • v.65 no.4
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    • pp.549-557
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    • 2022
  • Objective : This study analyzed the risk factors in patients who developed distal junctional kyphosis (DJK) after posterior cervical fusion. Methods : We retrospectively analyzed the clinical and radiographic outcomes of 64 patients, aged ≥18 years (51 and 13 male and female patients, respectively), who underwent single-staged multilevel (3-6 levels) posterior cervical fusion surgery due to multiple cervical spondylotic myelopathy. The surgeries were performed by a single spinal surgeon between January 2012 and December 2017. Demographic data, clinical outcomes, and radiological results were collected. We divided the patients into a DJK group and a non-DJK group according to the presence of DJK and investigated the risk factors by comparing the differences between the two groups. Results : Of the 64 patients, 13 developed DJK. No significant differences in clinical results were observed between the two groups before and immediately after the surgery. At the final follow-up, a higher visual analog score for neck pain was observed in the DJK group compared to the non-DJK group (p<0.01). The DJK group had a significantly lower T1 slope and a significantly higher C2-7 sagittal vertical axis (SVA) before surgery compared to the non-DJK group (p=0.03 and p<0.01, respectively). Immediately after surgery, the difference between the two groups decreased and no significant difference was observed. However, at the last follow-up, a significantly higher C2-7 SVA was observed in the DJK group (p<0.01). At the last follow up, there is no discrepancy in T1S-CL. In multiple logistic regression analysis, preoperative higher C2-7 SVA and preoperative lower T1 slope were identified as independent risk factors (p=0.03 and p<0.01, respectively). As a result, it was confirmed that DJK occurred along the process of returning to preoperative values. Conclusion : DJK can be considered to be caused by cervical misalignment due to excessive change in the surgical site in patients with low T1 slope and high C2-7 SVA before surgery. This also affects the clinical outcome after surgery. It is recommended to refrain from excessive segmental lordosis changes during multilevel cervical post fusion surgery, especially in patients with a small preoperative T1 slope and a large SVA value.

Geant4 Code Based Simulation of 6 MV Photon Beam for Analysis of Dose Distribution (Geant4 코드를 이용한 선형가속기 6 MV 광자선의 선량분포에 관한 연구)

  • Lee, Jun-Seong;Kim, Yang-Soo;Lee, Sun-Young
    • Journal of radiological science and technology
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    • v.45 no.5
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    • pp.449-455
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    • 2022
  • This study is to present a Geant4 code for the simulation of the absorbed dose distribution given by a medical linac for 6 MV photon beam. The dose distribution was verified by comparison with calculated beam data and beam data measured in water phantom. They were performed for percentage depth dose(PDD) and beam profile of cross-plane for two field sizes of 10 × 10 and 15 × 15 cm2. Deviations of a percentage and distance were obtained. In energy spectrum, the mean energy was 1.69 MeV. Results were in agreement with PDD and beam profile of the phantom with a tolerance limit. The differences in the central beam axis data 𝜹1 for PDD had been less than 2% and in the build up region, these differences increased up to 4.40% for 10 cm square field. The maximum differences of 𝜹2 for beam profile were calculated with a result of 4.35% and 5.32% for 10 cm, 15 cm square fields, respectively. It can be observed that the difference was below 4% in 𝜹3 and 𝜹4. For two field sizes of 𝜹50-90 and RW50, the results agreed to within 2 mm. The results of the t-test showed that no statistically significant differences were found between the data for PDD of 𝜹1, p>0.05. A significant difference on PDD was observed for field sizes of 10 × 10 cm2, p=0.041. No significant differences were found in the beam profile of 𝜹3, 𝜹4, RW50, and 𝜹50-90. Significant differences on beam profile of 𝜹2 were observed for field sizes of 10 × 10 cm2, p=0.025 and for 15 × 15 cm2, p=0.037. This work described the development and reproducibility of Geant4 code for verification of dose distribution.

A Study on the Characteristics of Rural Convention in Chungcheong Region - Focused on the Rural Spatial Structure Analysis, Setting of Rural Living Area and Use of Amenity Resource(Facility) - (충청지역의 농촌협약 특성에 관한 연구 - 농촌 공간구조 분석과 농촌생활권 설정, 농촌다움(시설)자원 활용을 중심으로 -)

  • Eom, Sung-Jun;Kim, Sang-Bum;An, Phil-Gyun
    • Journal of the Korean Institute of Rural Architecture
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    • v.24 no.4
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    • pp.41-48
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    • 2022
  • The purpose of this study is to present the implications of the rural living area setting and rural spatial structure analysis of the rural spatial strategy plan through case analysis. Following the decentralization of autonomy and the promotion of the transfer of state affairs to local areas, some of the general agricultural and fishing village development projects of the Ministry of Agriculture, Food and Rural Affairs were transferred to local areas. In addition, in 2020, the Ministry of Agriculture, Food and Rural Affairs introduced a rural agreement system for 113 cities and counties. However, since the understanding of the field is still low, this study attempted to present implications through a case analysis of the structure of rural space and the establishment of rural living areas in three local governments in Chungcheong. As a result of the study, in the stage of establishing the living zone, it is necessary to comprehensively review the contents reviewed in the analysis of the current status and conditions. However, the two local governments had insufficient interpretation of the axis by function and the establishment of the base area, or were using the upper plan as it was. Second, the source of the data used in the survey on the distribution status of living SOC facilities is unclear. Since the distribution status of living SOC facilities overlaps with accessibility analysis, OD data analysis, and resident survey results and is used as the basis for setting living areas, the data source should be clearly marked, and verification should be possible. Third, amenity (facility) resources were classified and analyzed according to the conditions and characteristics of local governments. The local government that applied the guidelines as they were was A local government, and the remaining local governments conducted surveys and analysis according to the current status. Forth, since the establishment of the rural living area is the minimum unit supported by government policies through future rural agreements, it is necessary to distinguish them based on quantitative standards in the process of establishing them. Only one case area presented clear grounds and standards, and the rest of the case areas presented standards but are based on non-quantitative standards. In order for rural agreements to be sustainable in the future and benefit local residents, it is necessary to use or establish a government-level institution that can collect and produce objective data. In addition, it is necessary to find ways to specify and standardize the standards for setting the living area and specify them in the guidelines.

Neurobiological Factors of Suicide (자살의 신경생물학적 요인)

  • Song, Hoo Rim;Woo, Young Sup;Jun, Tae Youn
    • Mood & Emotion
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    • v.10 no.1
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    • pp.13-21
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    • 2012
  • Suicide is a complex behavior associated with various neurobiological and psychosocial factors. It is considered that genetic polymorphism combined with environmental stress such as child-adolescent trauma make differences in neurobiological systems, which cause psychiatric disorders or pessimistic personality, impulse-aggressive behaviors, lack of judgment, and finally result in suicidal behavior. Much progress in the neurobiology of suicide has been made over the several decades. There seems to be a hereditary disposition to suicide independent of psychiatric disorder. The changes in neurotransmitters, neurohormones, neurotrophic factors, cytokines, lipid metabolisms related with their genetic polymorphism can contribute to disturbance of signal transductions and neuronal circuits vulnerable to suicide. It is likely that the main factors are dysfunctions of serotonin (5-HT) and hypothalamus-pituitary-adrenal (HPA) axis. Our understanding about the neurobiology of suicide is still limited. However, clinical practice could be assisted by neurobiological findings capable of making the detection of risk populations with higher sensitivity and the development of new treatment interventions. The settlement of biological markers in suicidal behaviors and their relationships is required.