• Structural Monitoring and Maintenance
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• 제5권1호
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• pp.67-78
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• 2018

The stability of cutting slope influences the safety of railway operation, and how to identify the stability of the slope quickly and determine the rational monitoring plan is a pressing problem at present. In this study, the attribute recognition model of risk assessment for high cutting slope stability in the heavy haul railway is established based on attribute mathematics theory, followed by the consequent monitoring scheme design. Firstly, based on comprehensive analysis on the risk factors of heavy haul railway loess slope, collapsibility, tectonic feature, slope shape, rainfall, vegetation conditions, train speed are selected as the indexes of the risk assessment, and the grading criteria of each index is established. Meanwhile, the weights of the assessment indexes are determined by AHP judgment matrix. Secondly, The attribute measurement functions are given to compute attribute measurement of single index and synthetic attribute, and the attribute recognition model was used to assess the risk of a typical heavy haul railway loess slope, Finally, according to the risk assessment results, the monitoring content and method of this loess slope were determined to avoid geological disasters and ensure the security of the railway infrastructure. This attribute identification- risk assessment- monitoring design mode could provide an effective way for the risk assessment and control of heavy haul railway in the loess plateau.

• 대한의용생체공학회:의공학회지
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• 제18권4호
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• pp.491-498
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• 1997

본 연구에서는 졸음운전 방지를 위한 방법으로 기존의 3단계 경고음법과 fuzzy logic을 이용한 가성도 측정 및 제어법을 시뮬레이션으로 비교 및 분석하였다. 각성상태를 제어하는 방법으로 사용되었던 기존의 각성제어지표는 실 차에는 사용될 경우 효과적이지 못하므로 각성상태에 따른 영역별 Nz와 IRI의 상관분포도를 분석하여 기존의 각성제어지표를 수정하였다. Fuzzy 추론으로는 Sugeno의 방법을 사용하였고 멤버쉽함수와 제어규칙 베이스는 수정된 각성제어지표로부터 결정하였다. 시뮬레이션 결과 60이하의 IRI가 발생되는 경우, Nz의 변화에 따라 두 제어방법 모두 small, medium, big의 경고음이 발생되었으나 3단계 경고음법은 다음 단계의 발생영역이 될 때까지 같은 출력만을 발생한다. 그러나 퍼지추론의 출력은 피검자의 각성수준의 변화에 잘 추종하여 변화되었으므로 3단계 경고음법의 문제점을 해겨할 수 있었고 더욱이 퍼지 추론의 출력과 Nz와의 상관계수(r=0.99)가 매우 높았으므로, 실제 운전시 퍼지추론 방법을 이용한 각성도 평가 및 제어에 적용할 경우 3단계 경고음법 보다 효과적일 것으로 기대된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.334-334
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• 2022

Improvement of old-fashioned rain gauge systems for automatic, timely, continuous, and accurate precipitation observation is highly essential for weather/climate prediction and natural hazards early warning, since the occurrence frequency and intensity of heavy and extreme precipitation events (especially floods) are recently getting more increase and severe worldwide due to climate change. Although rain gauge accuracy of 0.1 mm is recommended by the World Meteorological Organization (WMO), the traditional rain gauges in both weighting and tipping bucket types are often unable to meet that demand due to several existing technical limitations together with higher production and maintenance costs. Therefore, we aim to introduce a newly developed and cost-effective hybrid rain gauge system at 0.1 mm accuracy that combines advantages of weighting and tipping bucket types for continuous, automatic, and accurate precipitation observation, where the errors from long-term load cells and external environmental sources (e.g., winds) can be removed via an automatic drainage system and artificial intelligence-based data quality control procedure. Our rain gauge system consists of an instrument unit for measuring precipitation, a communication unit for transmitting and receiving measured precipitation signals, and a database unit for storing, processing, and analyzing precipitation data. This newly developed rain gauge was designed according to the weather instrument criteria, where precipitation amounts filled into the tipping bucket are measured considering the receiver's diameter, the maximum measurement of precipitation, drainage time, and the conductivity marking. Moreover, it is also designed to transmit the measured precipitation data stored in the PCB through RS232, RS485, and TCP/IP, together with connecting to the data logger to enable data collection and analysis based on user needs. Preliminary results from a comparison with an existing 1.0-mm tipping bucket rain gauge indicated that our developed rain gauge has an excellent performance in continuous precipitation observation with higher measurement accuracy, more correct precipitation days observed (120 days), and a lower error of roughly 27 mm occurred during the measurement period.

• 한국건설관리학회논문집
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• 제13권1호
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• pp.77-86
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• 2012

건설 프로젝트의 성과 측정 및 관리에 있어 진도관리는 기본적이며 핵심적인 업무기능이다. 오랜 기간 동안 다양한 진도 관리 기법이 연구 개발되고 있음에도 불구하고, 자료수집을 위한 과도한 업무부담은 체계화된 진도관리의 장애요소로 지적되어 왔다. 최근 자료수집기술(Data Acquisition Technology, DAT)의 발전은 자동화된 진도관리의 기회를 제공하고 하고 있다. 그럼에도 불구하고 지금까지의 DAT 연구는 특정 공종 또는 특정 기술에 집중하고 있어, 건설사업 전체의 진도관리 자동화에 대한 연구는 이루어지지 않았다. 이러한 관점에서, 본 연구는 건설사업 공종별 최적의 DAT를 선정하는 방법론을 제안하였다. DAT 선정방법은 각 공종별 진도측정의 방법, 대상, 범위, 기술 등의 유형을 분류하여, 이를 DAT 특성별로 최적치를 도출하는 알고리즘으로 구성된다. 제안된 방법론의 검증을 위하여 사례 프로젝트를 이용한 기계적 분석을 실시하고 또한 실무자 평가를 수행한 결과, 대부분 공종에서 동일한 결과를 얻었다. 또한 사례현장 평가결과 중의 하나로서, 노무자의 층별 출입정보를 RFID를 활용하여 측정하는 것이 가장 효율적이며 가장 많은 공종에 적용이 가능한 것으로 나타났다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.49.1-49.9
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• 2016

Background: The aim of this report is to present a new reference for aesthetic mandible surgery using three-dimensional cone-beam computed tomography-based treatment planning for orthognathic surgery which can be implemented in surgical planning and perioperative procedure. Methods: To make an objective standard for evaluating aesthetic mandibular outline, we make an aesthetic scoring criteria with consideration of asymmetry, broad mandibular border line, and prominent mandibular angle. Two maxillofacial surgeons and two orthodontists rated their aesthetical evaluation from 1 to 5. Experimental group consisting of 47 female and 38 male patients who had rotational orthognathic two-jaw surgery from 2010 to 2011 were chosen according to aesthetic scoring done by two maxillofacial surgeons and two orthodontists. A high aesthetic score (${\geq}16$) means the facial contour is symmetric, with no broad and narrow aesthetic mandible frontal profiles. Control A group consisted of ten female and ten male patients who had no orthognathic surgery experience and low aesthetic score (${\geq}10$). Control B group consisted of ten female and ten male patients who had no orthognathic surgery experience and had anaesthetic mandibular frontal profile and a high aesthetic score (${\geq}16$). The three-dimensional image of the patient was taken from dental cone-beam CT (DCT) scanning (experimental group and control A group: 6 months DCT after surgery, control B group: 1st visit DCT). Each DCT was reformatted to reorient the 3D image using 3D analyzing program (OnDemand3D, cybermed Inc, CA, USA). After selection of 12 landmarks and the construction of reoriented horizontal, vertical, and coronal reference lines, 15 measurements were taken in 3D analysis of frontal mandibular morphology. Afterwards, horizontal and vertical linear measurements and angular measurements, linear ratio were obtained. Results: Mean $Go^{\prime}_{Rt}-Me^{\prime}-Go^{\prime}_{Lt}$ angular measurement was $100.74{\pm}2.14$ in female patients and $105.37{\pm}3.62$ in male patients. These showed significant difference with control A group in both genders. Ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}-Me^{\prime}$ length to some linear measurements (ratio of $Me^{\prime}-Cd^{\prime}_{Rt}Cd^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Me^{\prime}-Go^{\prime}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$) showed significant difference with control A group in both genders. Conclusion: This study was intended to find some standard measurement of mandible frontal view in 3D analysis of aesthetic patient. So, these potential measurement value may be helpful for orthognathic treatment planning to have more aesthetic and perspective outcomes.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1374-1378
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• 2005

Appropriate upward force is crucial for the pantograph on high speed train to collect current from the catenery system without separation. However, at high speed, large aerodynamic lifting force is generated by the contact plate and the arms of pantograph, which may cause wear of the contact wire. In this study, to confirm the interface performance of the pantograph on Korea High Speed Train, a method to measure the contact force of the pantograph was proposed and the related measurement system was developed. The forces acting on the pantograph were clarified and a procedure to calculate the aerodynamic lifting force was proposed. A special device was invented and applied to measure the lifting force. Measured contact forces were displayed by the developed system and evaluated according to the criteria. Countermeasures were also taken to reduce the contact force based on the results.

• 대한통합의학회지
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• 제10권1호
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• pp.149-155
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• 2022

Purpose : This study investigated the effects of wearing a mask and different mask filters on the respiratory function of stroke patients. Methods : A total of 15 stroke patients were selected according to the inclusion and exclusion criteria. The respiratory functions were compared between participants with and without masks and among respiratory functions with three different mask filters. The order of using masks was non-wearing masks, Dental masks, KF80 masks, and KF94 masks; the difference in respiratory volumes among these conditions were measured. For accuracy of the measurement, sufficient education on the respiratory measurement method was provided to the researcher, and the heart rate of the participants was estimated to confirm their stability before the measurements. To ensure accuracy, the subjects were educated on the researchers' respiratory measurement methods. Each measurement was followed by 10 min breathing stability before replacing the next mask. Results : The results of this study showed that the difference in respiratory functions, including forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁), and maximal voluntary ventilation (MVV), in stroke patients was statistically significant among different masks (p<.05). Afterwards, the values of FVC, FEV₁, and MVV in stroke patients wearing masks were significantly lower than those of the non-masked control group (p<.05). The difference in respiratory functions with different mask filters showed no statistical significance (p<.05). Conclusion : This study showed that participants wearing any of the masks presented a lower respiratory function than that of those without using masks; additionally, no difference in respiratory functions was observed with differences in mask filters. Therefore, wearing a mask for a prolonged period is confirmed to affect breathing in stroke patients with weak respiratory function.

• 한국대기환경학회지
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• 제15권4호
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• pp.403-415
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• 1999

To properly assess air pollution levels, application of quality assurance and quality control(QA/QC) is believed to be an essential step. In order to cope with such scientific principle, a field study was designed with an aim of comparing: 1) the methods of calibration for airborne pollutants and 2) the protocols developed for their measurements. Measurements were made at Han Yang University, Seoul during 29 May through 1 June 1998 under the management of the Division of Measurements and Analysis(DMA) of Korean Society for Atmospheric Environment(KOSAE). In this work, we report our results of intercomparative measurements on several gaseous criteria pollutants that were investigated mainly by the two institutes-Seoul National University(SNU) and the Korean Research Institute for Standards and Science(KRISS). Although measurements of major gaseous pollutants had been made routinely by many scientific institutes and organizations in Korea, most scientists involved in those studieswere obliged to do their experiments on the basis of their own procedural steps spaning from the preparation of gaseous standards to the methodological selections for the calibration. Hence, this campaign offered a unique opportunity to examine many important aspects on the measurements of these important gaseous pollutants. In the course of our study, we investigated the compatibility of data sets obtained by the two institutes in concert with reference data sets collected concurrently from a government-managed monitoring station. On the basis of our study, we conclude that different data sets made by different participants during this campaign agree well within the reasonable range of uncertainties.low, which indicated that during this period the potential acidity of precipitation was high but the neutralizing capacity was low. For Spring, pAi was very low but pH was slightly high. This was likely due to the large amount of $CaCO_3$ in the soil particles transported over a long range from the Chinese continent that were incorporated into the precipitation, and then neutralized the acidifying species with its high concentraton.

• 사상체질의학회지
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• 제21권2호
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• pp.123-136
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• 2009

1. Objectives : This study is a pilot study to construct of metabolic syndrome model with constitutional type. We focused on the correlation of Metabolic syndrome(MetS) and ordinary symptoms with Taeumin at 40. 2. Methods : 32 subjects who had taken health examinations and diagnosis of Sasang constitution from Oct 1, 2008 to Dec 31, 2008 at Kyung-Hee medical center were included and underwent B-mode ultrasonography for measurement of intima-media thickness of common carotid arteries. MetS was defined by the criteria of the criteria of the National Cholesterol Education Program Adult Treatment Panel III. 3. Results and Conclusions : Mean intima-media thickness of common carotid artery was higher in subjects with MetS compared with control subjects(0.56$\pm$0.12 vs 0.54$\pm$0.08mm) however. The ordinary symptoms shown to differentiate the MetS group and the control group were related to "dark urine color," "dryness of eyes," and "night sweat". Therefore, these ordinary symptoms can be said to be indicators of the Taeumin with Mets syndrome.

• 산업경영시스템학회지
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• 제41권4호
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• pp.203-212
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• 2018

Quality requirements of manufactured products or parts are given in the form of specification limits on the quality characteristics of individual units. If a product is to meet the customer's fitness for use criteria, it should be produced by a process which is stable or repeatable. In other words, it must be capable of operating with little variability around the target value or nominal value of the product's quality characteristic. In order to maintain and improve product quality, we need to apply statistical process control techniques such as histogram, check sheet, Pareto chart, cause and effect diagram, or control charts. Among those techniques, the most important one is control charting. The cumulative sum (CUSUM) control charts have been used in statistical process control (SPC) in industries for monitoring process shifts and supporting online measurement. The objective of this research is to apply Taguchi's quality loss function concept to cost based CUSUM control chart design. In this study, a modified quality loss function was developed to reflect quality loss situation where general quadratic loss curve is not appropriate. This research also provided a methodology for the design of CUSUM charts using Taguchi quality loss function concept based on the minimum cost per hour criterion. The new model differs from previous models in that the model assumes that quality loss is incurred even in the incontrol period. This model was compared with other cost based CUSUM models by Wu and Goel, According to numerical sensitivity analysis, the proposed model results in longer average run length in in-control period compared to the other two models.