본 연구에서는 교정시설에서 종교인의 수용자에 대한 종교교화의 방식인 자원봉사 자로서의 비전임 교종인 종교위원제도의 고착되어온 다양한 문제점에 대한 경로혁신 적 방안의 하나로 전임교종(矯宗)의 도입의 필요성과 도입방식에 대한 방안을 모색할 목적으로 서술되었다. 이를 위하여 전임교종제의 도입에 있어 이해관계자인 교정공무 원 경력자들에 대한 질적 연구방법을 통해 현장의 생생한 의견과 인식을 자연스럽고 개방적 맥락에서 심층적으로 수집하고 분석함으로써 보다 실효적인 정책의제화와 입 법화의 실현에 기여할 수 있는 실천적 방안을 서술하였다. 특히 2009년에 법무부가 전임교종제를 도입하려다가 찬・반이 비슷해 제도도입을 보류한 상태이므로 법적, 과학적 근거만 충분히 입증되면 제도의 입법화가 가능한 상 태이다. 그런데 전임교종의 필요성에 관한 선행연구들이 추상적이거나 종교적 차원이어서 과학적・실천적 근거가 부족한 점에 착안하여 본 연구에서는 과학적 접근의 하나로 실 증적 연구인 질적 연구를 통해 전임교종의 필요성과 도입방식의 정책적 방안을 제시하였다. 연구결과 현재의 자원봉사식의 비전임 종교위원제도의 고질화된 문제점에 대 해 모든 연구 참여자들이 깊이 인식하였으며 근본대안으로 전임교종제도의 도입의 필 요성에 대해 공감하였다. 다만 전임교종제의 도입방식인 채용형식 등에 대해서는 여 러 의견이 있으므로 법무부는 이해관계자인 교도관과 종교위원들에 대한 과학적인 설 문조사를 통해 보류되어왔던 전임교종제의 도입여부에 대해 면밀한 검토를 할 시기가 되었다. 특히 전임교종제의 도입에 큰 거부점이 없고 종교계, 학계 등 접근점(access point)이 강한 상태이므로 조속히 정책의제화를 통해 전임교종제를 실시하는 것이 헌 법이념과 비교법적 차원 및 종교교육형주의의 실효성 확보에서 필요하다.
High voltage impulse (HVI) has been gained attention as an alternative technique that could control the CaCO3 scale problems encountered in water main, pipe, cooling tower and heat exchanger vessels. The aim of this study was to investigate the effect of electric field (E) and contact time (t) of HVI on reduction of Ca2+ concentration at two different temperatures of 25℃ and 60℃. A kinetic model on the effect of E and t was investigated too. As the E and t increased, the Ca2+ concentration decreased more than that of the control (= no HVI). The Ca2+ concentration decreased up to 81% at 15 kV/cm at 60℃, which was nearly 2 times greater than the control. With these experimental data-set of reduction of Ca2+ concentration under different E and t, the kinetic model was developed. The relationship between E and t required to reduce the concentration of Ca2+ by 30% was modeled at each temperature. The empirical model equations were; E0.83· t = 60.3 at 25℃ and E0.08· t = 1.1 at 60℃. These equations state the products of En and t is always constant, which means that the required contact time can be reduced in accordance with the increment of E and vice versa.
PURPOSES : The purpose of this study was to evaluate the newly developed Guss mastic asphalt mixtures, called EQ-mastic asphalt mixtures, which contain melted additives for decreasing cooking time.
METHODS : A series of experiments were performed to investigate the effectiveness of the melted additives in EQ-mastic asphalt mixtures. Both the existing Guss mastic asphalt mixture and the EQ-mastic asphalt mixture were produced with the same amounts of asphalt binders, aggregates, and fillers, but the existing Guss mastic asphalt mixture contained 3% Trinidad lake asphalt (TLA). The EQ-mastic asphalt mixture contained 3% of additives, including TLA and polyolefin. The physical material performances of both mastic asphalt mixtures were obtained by conducting the Luer fluidity test, penetration test, dynamic stability test, and low-temperature bending test. The results of the tests for the existing Guss mastic and EQ-mastic asphalt mixtures were compared.
RESULTS : The fluidity, penetration, dynamic stability, and low-temperature bending strains of both the existing Guss mastic and EQmastic asphalt mixtures all satisfied the standard values provided in the production and construction guides of the Guss mastic asphalt pavement.
CONCLUSIONS : When melted additives containing polyolefin are used in the production of Guss mastic asphalt mixtures, the cooking time decreases, so that the corresponding energy consumption and asphalt fume amount can be reduced. Therefore, an EQ-mastic asphalt mixture is proposed for use as an eco-friendly pavement material.
PURPOSES : The driver's ability to make a commitment has resulted in excessive force and a lack of commitment. To solve this problem, we are developing an algorithm that analyzes resolution in real-time by introducing IoT and informs drivers of the completion of compaction. METHODS : Real-time compaction was analyzed by installing accelerometers on the rollers. To evaluate the algorithms, we conducted an apparent density test.
RESULTS : The algorithm data and apparent density test data showed similar trends. This means that the proposed algorithms are sufficiently reliable. However, a lack of data samples and the fact that only data prior to completion of the commitment were analyzed may indicate a lack of reliability.
CONCLUSIONS : In subsequent studies, the number of samples will be increased and the data after completion of the commitment analyzed to increase reliability. Introducing a tachometer will prevent the TVL from falling sharply when the direction of the rollers' progress changes. In addition, it is also planned to upgrade the algorithms by researching cases in which the algorithms did not produce satisfactory results owing to problems such as temperature and speed.
The choice of the culture medium is an important factor for the mass production of mycelia in submerged cultures. The influence of liquid medium on the mycelial dry weight of Paecilomyces tenuipes was investigated in this study. The regression equation is expressed as Y=-1292.94187+17.78612X1+18.92425X2+2.11464X3-0.019375X1X2-0.006276X1X3+0.008177X2X3- 0.070169X1 2-0.292175X2 2-0.008818X3 2, where Y represents the value of the mycelial dry weight (g/L), X1 is the particle size of wood sawdust in liquid medium (mesh), X2 is the concentration of the wood sawdust in liquid medium, and X3 is incubation time (h). The medium was optimized using a response surface methodology, and the optimal medium contained 30 g of wood sawdust (140 mesh), 20 g of glucose, and 10 g/L of peptone. Under these conditions, the mycelial dry weight reached 38.1 g/L (actual value). The culture medium containing wood sawdust is simple and easy to use, highly efficient, and eco-friendly, and its effectiveness in large preparations of P. tenuipes mycelia with low material costs has been demonstrated.
The leading source of occupational fatalities is a portable ladder in Korea because it is widely used in industry as work platform. In order to reduce victims, it is necessary to establish preventive measures for the accidents caused by portable ladder. Therefore, this study statistically analyzed injury death by portable ladder for recent 10 years to investigate the accident characteristics. Next, to monitor wearing of safety helmet in real-time while working on a portable ladder, this study developed an object detection model based on the You Only Look Once(YOLO) architecture, which can accurately detect objects within a reasonable time. The model was trained on 6,023 images with/without ladders and safety helmets. The performance of the proposed detection model was 0.795 for F1 score and 0.843 for mean average precision. In addition, the proposed model processed at least 25 frames per second which make the model suitable for real-time application.
Non-face-to-face online education which suddenly began with COVID-19, was an opportunity to expand to university education sites. This study presents online classes based on the Tandem learning method as examples and examines the class operation, learning content, and learner satisfaction according to the actual type of flip learning classes and real-time video classes. By converting Tandem classes operated by B University in Busan into online classes, the existing e-Tandem classes were expanded using flip learning and ZOOM. The first Flip learning class allows self-directed learning, and the free form of learning through pre-learning becomes an advantage of the online class type. However, while professors participate in the small conference room and feedback, there is a need to be supplemented with the ability to feedback directly to other teams. Furthermore, as a result of the learner satisfaction survey, there were complaints about prior learning and the amount of tasks, so studies on specific tasks and the content and methods of prior learning are also needed. The second real-time video class allows interaction between professors and learners, learners and learners. The biggest feature of this class type is that it can solve the absence of communication, which was a disadvantage of non-face-to-face classes. However, the ability of a professor is needed to conduct a real-time video class like this. Unlike learners who are familiar with digital technology, only when they understand and learn various online content and functions will their online classes become as natural as face-to-face classes.
Seismic designs for Korean nuclear power plants (NPPs) under earthquakes’ design basis are noticed due to the recent earthquake events in Korea and Japan. Japan has developed the technologies and experiences of the NPPs through theoretical research and experimental verification with extensively accumulated measurement data. This paper describes the main features of the design-time history complying with the Japanese seismic design standard. Proper seed motions in the earthquake catalog are used to generate one set of design time histories. A magnitude and epicentral distance specify the amplitude envelope function configuring the shape of the earthquake. Cumulative velocity response spectral values of the design time histories are compared and checked to the target response spectra. Spectral accelerations of the time histories and the multiple-damping target response spectra are also checked to exceed. The generated design time histories are input to the reactor building seismic analyses with fixed-base boundary conditions to calculate the seismic responses. Another set of design time histories is generated to comply with Korean seismic design procedures for NPPs and used for seismic input motions to the same reactor containment building seismic analyses. The responses at the dome apex of the building are compared and analyzed. The generated design time histories will be also applied to subsequent seismic analyses of other Korean standard NPP structures.
This paper presents a real-time, false-pick filter based on deep learning to reduce false alarms of an onsite Earthquake Early Warning (EEW) system. Most onsite EEW systems use P-wave to predict S-wave. Therefore, it is essential to properly distinguish P-waves from noises or other seismic phases to avoid false alarms. To reduce false-picks causing false alarms, this study made the EEWNet Part 1 'False-Pick Filter' model based on Convolutional Neural Network (CNN). Specifically, it modified the Pick_FP (Lomax et al.) to generate input data such as the amplitude, velocity, and displacement of three components from 2 seconds ahead and 2 seconds after the P-wave arrival following one-second time steps. This model extracts log-mel power spectrum features from this input data, then classifies P-waves and others using these features. The dataset consisted of 3,189,583 samples: 81,394 samples from event data (727 events in the Korean Peninsula, 103 teleseismic events, and 1,734 events in Taiwan) and 3,108,189 samples from continuous data (recorded by seismic stations in South Korea for 27 months from 2018 to 2020). This model was trained with 1,826,357 samples through balancing, then tested on continuous data samples of the year 2019, filtering more than 99% of strong false-picks that could trigger false alarms. This model was developed as a module for USGS Earthworm and is written in C language to operate with minimal computing resources.
PURPOSES : This study defines travel time reliability as a concept that explains the change in travel time that passengers can hardly predict and calculates the value of travel time reliability based on travel objectives.
METHODS : Because the reliability of passage time is difficult to estimate from actual passenger data, standard quantification measures have not been established despite various interests. In this study, the reliability of transit time was defined as the expense that passengers did not recognize in advance, such as an accidental delay caused by unforeseen circumstances. For analysis based on the individual behavior of users, the data were constructed using the optional experiment method (marginal rate of substitution method) of the stated preference survey, which has the advantage of controlling the correlation between attribute variables and maintaining the independence of the data of the study.
RESULTS : Consequently, the reliability value of travel time in mandatory-purposed traffic was almost identical to the value of travel time, and the reliability value of travel time in return and shopping/leisure, which is not mandatory during non-business-purpose traffic, is lower than the value of travel time. Comparing and analyzing with existing studies on estimating the reliability value of transit time, both work/ non-work purposes are in line with the overall research results. CONCLUSIONS : Estimating the reliability value of transit time for each purpose of passage was the first attempt, and it is meaningful to suggest a direction for quantifying and applying the reliability value of transit time along with the passage time value of this study.
본 연구는 선박용 공기압축기의 상태기반보전 시스템에 필요한 이상치 탐지 알고리즘 적용에 대한 실험적 연구로서 고장모사 실험을 통해 시계열 전류 센서 데이터를 이용한 이상탐지 적용 가능성을 확인하였다. 고장 유형 10개에 대해 실험실 규모의 고장 모사 실험을 수행하여 정상 운전데이터와 고장 데이터를 구축하였다. 실험 결과 구축된 이상탐지 모델은 시계열 데이터의 주기에 변화를 유발하는 이상은 잘 탐지하는 반면 미세한 부하 변동에 대한 탐지 성능은 떨어졌다. 또한 오토인코더를 이용한 시계열 이상탐지 모델은 입력 시 퀀스의 길이와 초모수 조정에 따라 이상 탐지 성능이 상이한 것으로 나타났다.
머신러닝 기법의 발달과 함께 기계에서 발생하는 다양한 종류(진동, 온도, 유량 등)의 데이터를 활용하여 기계의 상태를 진단하고 이상 탐지 및 비정상 분류 연구도 활발히 진행되고 있다. 특히 진동 데이터를 활용한 회전 기계의 상태 진단은 전통적인 기계 상태 모니터링 분야로 오랜 기간 동안 연구가 진행되었고, 연구 방법 또한 매우 다양하다. 본 연구에서는 가정용 에어컨에 사용되는 로터리 압축기에 가속도계를 직접 설치하여 진동 데이터를 수집하는 실험을 진행하였다. 데이터 부족 문제를 해결하기 위해 데이터 분할을 수행하였으며, 시간 영역에서의 진동 데이터로부터 통계적, 물리적 특징들을 추출한 후, Chi-square 검증을 통해 고장 분류 모델의 주요 특징을 추출하였다. SVM(Support Vector Machine) 모델은 압축기의 정상 혹은 이상 유무를 분류하기 위해 개발되었으며, 파라미터 최적화를 통해 분류 정확도를 개선하였다.
전 세계 다양한 국가들을 비롯하여 우리나라도 생물다양성을 보전하기 위한 노력에 동참하고 있다. 특히 생물종과 관련해서는 특정 생물종을 대상으로 서식적합분석을 실시하여 잠재적인 서식 적지를 찾고 보전방안을 수립하는 연구들이 활발하게 수행되고 있다. 그러나 현재까지 축적된 정보를 바탕으로 한 서식적합지역의 중장기 변화에 대한 연구는 미흡한 실정이다. 이에 본 연구는 강원도 지역을 대상으로 멸종위기 야생생물 1급으로 지정된 수달을 대상으로 서식적합지역의 시계열 변화를 분석하고 변화 양상을 살펴보고자 하였다. 시계열 변화 분석을 위해서 약 20년간 수행된 2차, 3차, 4차 전국자연환경조사의 수달 종 출현지점 조사자료를 이용하였다. 또한 각 조사시기 별 서식환경을 반영하기 위해 조사시기와 일치하는 토지피복도를 환경변수 제작에 활용하였다. 서식적합지역 분석을 위해서는 종의 출현 정보만을 바탕으로 모델 구동이 가능하며, 선행연구를 통해 신뢰도가 높다고 입증된 MaxEnt 모형을 사용하였다. 연구결과, 각 조사시기 별 수달의 서식적합지역 지도가 도출되었으며, 하천을 중심으로 서식지가 분포하는 경향이 나타났다. 모델링 결과 도출된 환경변수의 반응곡선을 비교하여 수달이 선호하는 서식지의 특성을 파악하였다. 조사시기 별 서식 적지의 변화를 살펴본 결과, 2차 전국자연환경조사를 기반으로 한 서식 적지가 가장 넓은 분포를 나타냈으며, 3, 4차 조사의 서식 적지는 면적이 줄어드는 경향을 나타냈다. 또한, 3개 조사시기 분석결과를 종합하여 서식 적지의 변화 양상을 분석하고 유형화하였다. 변화 유형에 따라서 현장조사, 모니터링, 보호지역 설정, 복원계획과 같이 서로 다른 보전계획을 제안하였다. 본 연구는 수달 서식 적지의 위치와 면적의 시계열 변화를 볼 수 있는 종합분석 지도를 제작하고, 지역별 서식 적지 변화 유형에 따라 필요한 보전계획을 제안하였다는 점에서 의의를 갖는다. 본 연구에서 제안된 방법과 결과는 향후 서식지 보전 및 관리 방안 수립을 위한 기초자료로 활용될 수 있을 것으로 사료된다.