• Nuclear Engineering and Technology
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• 제47권7호
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• pp.804-813
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• 2015

The electrical-impedance method has been widely used for void-fraction measurement in two-phase flow due to its many favorable features. In the impedance method, the response characteristics of the electrical signal heavily depend upon flow pattern, as well as phasic volume. Thus, information on the flow pattern should be given for reliable void-fraction measurement. This study proposes an improved electrical-conductance sensor composed of a three-electrode set of adjacent and opposite electrodes. In the proposed sensor, conductance readings are directly converted into the flow pattern through a specified criterion and are consecutively used to estimate the corresponding void fraction. Since the flow pattern and the void fraction are evaluated by reading conductance measurements, complexity of data processing can be significantly reduced and real-time information provided. Before actual applications, several numerical calculations are performed to optimize electrode and insulator sizes, and optimal design is verified by static experiments. Finally, the proposed sensor is applied for air-water two-phase flow in a horizontal loop with a 40-mm inner diameter and a 5-m length, and its measurement results are compared with those of a wire-mesh sensor.

• 상하수도학회지
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• 제31권3호
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• pp.249-256
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• 2017

Recently, application areas based on M2M (Machine-to-Machine communications) and IoT (Internet of Things) technologies are expanding rapidly. Accordingly, water flow and water quality management improvements are being pursued by applying this technology to water and sewage facilities. Especially, water management will collect and store accurate data based on various ICT technologies, and then will expand its service range to remote meter-reading service using smart metering system. For this, the error in flow rate data transmitting should be minimized to obtain credibility on related additional service system such as real time water flow rate analysis and billing. In this study, we have identified the structural problems in transmitting process and protocol to minimize errors in flow rate data transmission and its handling process which is essential to water supply pipeline management. The result confirmed that data acquisition via communication system is better than via analogue current values and pulse, and for communication method case, applying the industrial standard protocol is better for minimizing errors during data acquisition versus applying user assigned method.

• 디자인학연구
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• 제11권3호
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• pp.187-196
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• 1998

시각적으로 부적절하고 부담스러운 요소 등을 감소시킬 필요성의 인식 하에 시각 흐름상 정보를 보다 효율적으로 파악할 수 있는 구체적이고 실증적인 방법을 제시하고자 정보의 기본적 전달 매개체인 텍스트를 대상으로 지면에서의 시각 흐름의 특징들과 이에 영향을 미치는 타이포그래피적 요인들을 살펴보고, 나아가 시각 흐름에 영향을 미치는 실제 요인들 중에서의 몇 가지를 추출하여 시각 흐름상 유의미한 차이가 있는지 실험으로써 검증하였다. 그 결과, 효율적인 글자 크기와 글줄 길이 간의 관계는 약 1:8의 비율을 보였다. 또한 지면에서의 텍스트 배열 중에서 글줄 길이에 상관없이 세로로 배열의 효율성이 가장 높다는 것을 확인하였다. 더욱이, 세로로 긴 텍스트의 경우에서 왼쪽에서 오른쪽으로 흐르는 층계 배열보다 세로 배열의 읽기 속도가 빠름을 볼 때, 컬럼 간의 실질적인 눈의 이동 거리를 좁히는 것보다 읽는 방향과 배열을 일치시키는 것이 더욱 효율적인 시각 흐름을 알 수 있다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.127-131
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• 2004

A low-cost, simple strip reader system using a linear movement mechanism of CD-ROM deck has been developed to characterize a lateral flow membrane-based immunochromatographic assay. The test strip reader was assembled by a CD-ROM deck and home-made optical head especially designed for immunoassays. The optical head for detecting reflected light from the test strip surface consists of green light-emitting diode, large area silicon photodiode, and anodized aluminum mounting block providing a slit structure for cutting light from the LED. The stepping motor of the deck was operated in the full step mode, whose distance of each reading point is about 0.15mm. The performance of the strip reader was tested by analysis of HBV(hepatitis B virus) antigen test kit. This strip reader can be useful for inexpensive, disposable, and membrane-based assays that provide visual evidence of the presence of an analyte in a liquid sample.

• 품질경영학회지
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• 제51권1호
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• pp.19-36
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• 2023

Purpose: The purpose of this study is to empirically verify the structural relationship between public library service-scape, flow, user satisfaction, and customer loyalty for adults who use public libraries for academic purposes in a changing public library environment. To this end, this study reviewed the concepts of public library service-scape, immersion, user satisfaction, and customer loyalty with existing literature, proposed a research model based on this, and empirically verified them. Methods: This study collected and statistically analyzed data for adults using public libraries for the purpose of reading books or studying. The collected data were checked using SPSS 24.0 and AMOS 24.0 and the research hypothesis was verified by analyzing the results using the structural equation modeling technique. Results: The results of the study are as follows. First, spatiality, aesthetics, and amenity of service-scapes have a positive effect on flow. Second, spatiality and amenity of service-scapes have a positive effect on user satisfaction. Third, Flow has a positive effect on user satisfaction. Fourth, Flow and user satisfaction have a positive effect on customer loyalty. Conclusion: This study is meaningful in that it suggests a strategic direction to enhance the service competitiveness of public libraries by strengthening the service-scape.

• 한국가스학회지
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• 제27권2호
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• pp.57-64
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• 2023

가스계량기의 검침방식이 발전하면서 원격검침이 가능한 스마트 가스 계량기(누출점검용 계량기 및 다기능 안전 계량기)가 사용되고 있다. 이러한 계량기는 부가기능으로 수집하는 유량 및 압력 데이터를 활용하여 누출 판단을 하는 기능이 있다. 유량 데이터를 이용한 누출판단 기능은 실제 현장에서 유효한 사례가 있지만 압력 데이터 기반 누출 판단 기준은 누출로 인한 압력 값 변화뿐만 아니라 여러 요인(정압기 압력 크기, 인접 계량기 연계, 인접 주택 사용량, 계량기 위치 등)으로 압력 크기 변화(레벨)가 있는 문제점이 있다. 본 논문에서는 스마트 가스계량기에서 수집되는 압력데이터를 활용하여 누출여부를 판단 할 수 있는 기법으로 압력 데이터 전처리 방법과 누출 여부 관련 압력 값 범위 기준, 누출판단 기법 및 적용 사례 검증을 통해 개발하였다.

• 대한의생명과학회지
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• 제18권4호
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• pp.399-405
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• 2012

The brain is the body's most organized and controlled organ, and it governs various psychological and mental functions. A brain abnormality could greatly affect one's physical and mental abilities, and consequently one's social life. Brain disorders can be broadly categorized into three main afflictions: stroke, brain tumor, and dementia. Among these, stroke is a common disease that occurs owing to a disorder in blood flow, and it is accompanied by a sudden loss of consciousness and motor paralysis. The main types of strokes are infarction and hemorrhage. The exact diagnosis and early treatment of an infarction are very important for the patient's prognosis and for the determination of the treatment direction. In this study, texture features were analyzed in order to develop a prototype auto-diagnostic system for infarction using computer auto-diagnostic software. The analysis results indicate that of the six parameters measured, the average brightness, average contrast, flatness, and uniformity show a high cognition rate whereas the degree of skewness and entropy show a low cognition rate. On the basis of these results, it was suggested that a digital CT image obtained using the computer auto-diagnostic software can be used to provide valuable information for general CT image auto-detection and diagnosis for pre-reading. This system is highly advantageous because it can achieve early diagnosis of the disease and it can be used as supplementary data in image reading. Further, it is expected to enable accurate medical image detection and reduced diagnostic time in final-reading.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제23권1호
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• pp.1-26
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• 2020

본 연구에서는 예비교사와 경력교사가 수학 수업지도안을 읽고 이해하는 과정을 시선 추적(Eye-tracking)을 통해 분석하였다. 두 그룹의 시선 데이터를 분석한 결과, 예비 교사들은 수학 수업지도안을 경력교사에 비해 어렵게 느끼고 있었으며 선조적인 방식으로 수학 수업지도안을 읽고 이해하였다. 반면, 경력교사들은 수학 수업지도안의 흐름을 파악하기 위해 핵심 주제어들을 찾아 연결성을 만들어가는 하이퍼텍스트 읽기 전략을 활용하였으며 수학 수업모형의 핵심 영역을 방문하는 시간이 유의미하게 길었다. 이러한 결과를 바탕으로 예비교사들이 수학 수업지도안을 읽고 이해하는 역량을 지도할 때 숙고해야할 여러 시사점들을 도출하였다.

• 한국항공운항학회지
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• 제23권3호
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• pp.18-27
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• 2015

Many studies have shown that having perception of spatial information is important for air traffic control officer (ATCO) since it helps them understand the current situation and predict the situation it leads to. However, little or no research has been done to investigate if there is any difference at the levels of expertise in perceiving spatial information and predicting a prospective situation. This study investigates the difference between expert and novice ATCO groups in how accurately each group of ATCO perceive spatial information such as position, altitude, speed, and flying direction, and predicting such information they will encounter shortly. In completing a task to watch the movement of airplanes displayed on the computer monitor as a blip, the participants were asked to predict the position, speed, and the altitude of the aircraft in a minute by marking on the sector map. The results show that the expert group performed better in accuracy and had tendency to overestimate on position and altitude; however, no significant difference was found between the two groups in terms of reading a flying direction. Therefore reading a flying direction may not be a reliable indicator to judge expertise of ATCO. But the expert group shows better predicting performance by perceiving spatial information such as airplane's position and altitude with feeling on time. The study suggests that it is important to enhance perceptive skills in ATCO training in improving their expertise in predicting accuracy traffic situation, preventing from air collision, and improving productivity for more efficient air traffic flow. A further study on the relationship between the perception of spatial information and the sense of time in predicting future information and effectiveness as an independent factor would contribute to providing more insights into expertise of ATCOs.

• 한국실내디자인학회논문집
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• 제15권5호
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• pp.230-237
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• 2006

The purpose of this study was to propose a plan of Information Resource Center(IRC) with various multimedia and Internet materials applicable in class for 'K' Elementary School in Daejeon. As for research methods, this study reviewed the basic directions and characteristics of Information Resource Center(IRC) defined by the Ministry of Education and Human Development, and literature from various sources. Standards for the Information Resource Center(IRC) were suggested, a plan was proposed according to them. Ultimately, a plan with stable and flexible layout and flow lines, facilities and spaces within the Information Resource Center(IRC) was established and executed. The basic functions of Information Resource Center(IRC) were information, reading, consultation, graphic production. The spaces suggested in this study for the Information Resource Center(IRC) for elementary school were space for the literature information, information search, A/V information, studying, browsing, reading. This results will support teacher's teaching with various multimedia and Internet materials applicable in class, help student's self directed learning activity, and play its role as a cultural center of the local community.