The main problem of airport noise is the impact of aircraft noise on the residents around the airport. In order to investigate the noise situation of a certain airport in South Korea, this article selects Muan Airport as the research project, selects five measurement points near the airport, takes aircraft takeoff as an example, measures the maximum noise level of each measurement point during each take off, and uses the American Airport Noise Prediction Software (AEDT 3C) to predict the noise of a single aircraft during take off, Calculate the contour area and sound exposure level data for four aircraft models. The results indicate that the average maximum noise level error between the measurement results and the simulation results is within 2dB, and the maximum noise level ranges from 65.1 to 88.1 decibels with the measurement range.
To non-destructively determine the burnup of a spent nuclear fuel assembly, it is essential to analyze the nuclear isotopes present in the assembly and detect the neutrons and gamma rays emitted from these isotopes. Specifically, gamma-ray measurement methods can utilize a single radiation measurement value of 137Cs or measure based on the energy peak ratio of Cs isotopes such as 134Cs/137Cs and 154Eu/137Cs. In this study, we validated the extent to which the results of gamma-ray measurements using cadmium zinc telluride (CZT) sensors based on 137Cs could be accurately simulated by implementing identical conditions on MCNP. To simulate measurement scenarios using a lead collimator, we propose equations that represent radiation behavior that reaches the detector by assuming “Direct hit” and “Penetration with attenuation” situations. The results obtained from MCNP confirmed an increase in measurement efficiency by 0.47 times when using the CZT detector, demonstrating the efficacy of the measurement system.
This study was conducted to verify the reliability of volatile organic compounds (VOCs) data derived from Selected Ion Flow Tube-Mass Spectrometers (SIFT-MS) measurements. In the previous study, the measurement reliability was validated using simultaneous measurements by SIFT-MS and gas chromatography-mass spectrometry (GS-MS), but in order to ensure more accuracy, and additional analysis was conducted by diluting standard gases (2 ppm) consisting of 10 types of VOCs mainly measured in industrial complexes (concentrations ranged from 0 to 500 ppb). As a result of 2 experiments, the SIFT-MS showed linearity and produced a coefficient of determination of over 0.99 for all cases. SIFT-MS has secured high measurement reliability, and it is considered to be able to efficiently manage VOCs emitted in industrial complexes.
In this study, data on indication errors within the range of 0 to 10 mm were measured using a dial gauge, which is widely used as a comparative measuring instrument in the field. Using Minitab, a statistical program, measurement conditions were determined during calibration of measuring instruments. Since the P value of the test statistic for the indication error is 0.000 to 0.003, the alternative hypothesis (H1) that no significant difference occurs due to a change in the measurement point at the significance level of 0.05 was adopted.
Painting pretreatment is an important task in determining the life of painting as it removes rust or foreign substances from the painting surface and gives adhesion between the painting surface and the painting surface. Since painting pretreatment is an important task, IMO strictly requires that the painting pretreatment surface be maintained at a Sa 2.5 grade and the surface roughness is 30μm~75μm. Painting pre-processing is an important task that determines the lifespan of a painting, but it is done through visual inspection by the inspector, and the quality varies depending on the inspector. In this study, in order to develop a quality measurement system for the painting pretreatment surface, Matlab2023b was used to determine the range of appropriate quality brightness by comparing the brightness of the painting pretreatment surface and surface roughness.
This study investigates the utilization of existing CCTV networks for road traffic volume measurement, a key indicator of road infrastructure utility. Traditionally, traffic studies, which are costly and time-consuming, are divided into continuous or ad-hoc surveys. By leveraging current CCTV systems, the proposed method eliminates the need for new installations, conserving resources and increasing efficiency. Preliminary results indicate that this approach offers a time and cost-effective alternative for traffic assessments, with the potential to transform traditional survey techniques.
When decommissioning a nuclear power plant, it is expected that clearance or radioactive waste (e.g., soil, concrete, metal, etc.) below the low-level will be generated in a short period on a large scale. Among the various types of waste, most of the contaminated soil is known to be classified as clearance or the (very) low-level radioactive waste. Accordingly, an accurate measurement and classification of contaminated soil in real-time during the decommissioning process can efficiently reduce the amount of soil waste and the possibility of contamination diffusion. However, in order to apply a system that measures and classifies contaminated soil in real-time according to the level of contamination to the decommissioning site, a demonstration is required to evaluate whether the system is applicable to the site. In this study, to establish requirements for determining the applicability of the system to the decommissioning site, preceding cases from countries with abundant decommissioning experience were investigated. For example, MACTEC of the U.S. demonstrated the developed system at the Saxton nuclear power plant in the U.S. and confirmed that the amount of soil that can be analyzed per hour in the system is affected by radionuclides, minimum detectable activity (MDA), and applicable volume. In the future, therefore, we will utilize the result of this study to develop the requirements of demonstrating the system for measurement and classification of contaminated soil in real-time.
Out-of-roundness is crucial for the proper functioning of individual products or parts in a machine. Mechanical components often consist of circular elements that require precise alignment. These circular parts are used in critical areas of the machine, and the shape characteristics of each component can significantly impact overall performance. In this study, we focus on a specific specimen and use three different methods - the Diameter method, Radius method, and Three-point method - to measure its out-of-roundness. The collected data is then analyzed using one-way ANOVA to propose an effective out-of-roundness measurement technique suitable for industrial settings.
The CMM is the most widely used measuring device in the field. The three-dimensional measurement method is divided into a method of scanning the shape of a product and a touch method. In this study, the accuracy of the dimension and shape of each measurement point touch method was analyzed based on the measured value with the touch method CMM using the inner and outer diameter measurement specimens. Through the experimental results, it was possible to obtain the closest value to the true value at more than 30 measurement points.
Noise is a sound that people don't want. In this study, noise is measured for SR20, a general aviation trainer used in Korea. In addition, noise measurement points are selected at Muan Airport, where most of the domestic trainers fly under the supervision of the Ministry of Land, Infrastructure and Transport, and the measured data are analyzed based on this. We also want to analyze the noise characteristics of SR20 aircraft through frequency analysis of the noise characteristics of SR20 aircraft are unique. We want to use this to understand what type of noise the trainer affects in future studies. this study will improve the reliability of the noise prediction scenario by comparing and analyzing the actual measured and predicted values when using the noise prediction program.
This study developed and evaluated a load cell-based automatic weighing system for the automated harvesting of laver (Porphyra tenera) in seaweed aquaculture. The current manual harvesting process was compared with the load cell-based automated system, and quantitative measurements of time, distance, and weight were conducted. The results demonstrated that the load cell-based system reduced the unloading time and increased the throughput compared to the manual method. In addition, statistical analysis confirmed that there was no significant difference from the mean in the weight measurement obtained using the load cell-based system. Based on these findings, the load cell-based automatic weighing system holds potential for efficient production and transactions in laver cultivation, contributing to cost reduction and improving the quality of life for aquaculture workers.
Recent studies have examined the correlation between erotic capital and luxury brands, which is essential to social success. However, limitations of such research have been noted due to the ambiguity of the concept and measurement of erotic capital. Therefore, in this study, we clarify the components of erotic capital and develop measurement tools to study the expansion of the base of luxury brands. To this end, a survey targeted 200 consumers who had purchased luxury brands within six months. The results of this study show that the attraction value of individuals and expected social success increases purchases of luxury products. This study suggests that marketers of luxury brands based on traditional values should reflect the concept of erotic capital for product planning, promotion, and marketing to expand the consumer base.
본 연구는 조현병으로 진단된 환자들과 정상 대조군 간의 자기공명영상을 사용하여 대뇌 피질 하부 영역의 부피를 측정 하여 대뇌의 구조적 이상을 비교하였다. 자기공명영상 검사 후 획득된 3D T1-MPRAGE 영상과 FreeSurfer 소프트웨어 를 사용하여 대뇌 피질 하의 31개 영역의 부피를 측정하였다. 연구 결과는 조현병 환자군에서 양측 측뇌실, 양측 맥락얼기, 제3뇌실, 뇌척수액 영역의 부피가 정상 대조군보다 유의하게 증가했으며, 좌 우반구 피질, 좌측 시상, 좌측 해마 영역의 부피는 정상 대조군보다 유의하게 감소하였다. 또한, 측정된 대뇌의 부피값과 PANSS 총점수는 약한 음의 상관관계를 나타 내었다. 따라서, 본 연구에서는 자기공명영상과 FreeSurfer를 이용하여 조현병 환자의 대뇌 피질 하 부피를 측정하고 이를 정상 대조군과 비교하여 유의한 증가와 감소를 확인하였다.
Our research team has developed a gamma ray detector which can be distributed over large area through air transport. Multiple detectors (9 devices per 1 set) are distributed to measure environmental radiation, and information such as the activity and location of the radiation source can be inferred using the measured data. Generally, radiation is usually measured by pointing the detector towards the radioactive sources for efficient measurement. However, the detector developed in this study is placed on the ground by dropping from the drone. Thus, it does not always face toward the radiation source. Also, since it is a remote measurement system, the user cannot know the angle information between the source and detector. Without the angle information, it is impossible to correct the measured value. The most problematic feature is when the backside of the detector (opposite of the scintillator) faces the radiation source. It was confirmed that the measurement value decreased by approximately 50% when the backside of the detector was facing towards the radiation source. To calibrate the measured value, we need the information that can indicate which part of the detector (front, side, back) faces the source. Therefore, in this study, we installed a small gamma sensor on the backside of the detector to find the direction of the detector. Since this sensor has different measurement specifications from the main sensor in terms of the area, type, efficiency and measurement method, the measured values between the two sensors are different. Therefore, we only extract approximate direction using the variation in the measured value ratio of the two sensors. In this study, to verify the applicability of the detector structure and measurement method, the ratio of measured values that change according to the direction of the source was investigated through MCNP simulation. The radioactive source was Cs-137, and the simulation was performed while moving in a semicircular shape with 15 degree steps from 0 degree to 180 degrees at a distance of 20 cm from the center point of the main sensor. Since the MCNP result indicates the probability of generating a pulse for one photon, this value was calculated based on 88.6 μCi to obtain an actual count. Through the ratio of the count values of the two sensors, it was determined whether the radioactive source was located in the front, side, or back of the probe.
Microclimate analysis was conducted through actual measurement according to land use status in urban, and CFD analysis was conducted to analyze and predict the microclimate characteristics of urban, and compared and analyzed with the actual measurement results. It was measured in high-rise areas and parks, and the temperature of the park area was 0.4 to 0.6℃ lower, and the relative humidity was 1.0 to 3.0% higher. The correlation coefficient was obtained by comparing the results of the computational fluid analysis with the results of the computational fluid analysis at the actual location located within the CFD analysis area for validation. The seasonal correlation coefficients are all higher than 0.8, so it is judged that they can be applied to microclimate analysis in urban area. The computational fluid analysis was divided into three areas (low-rise, low and high-rise, and high-rise) centered on the A2 point. On average, the low-rise area was 0.1 to 0.4% higher than the high-rise area. In the low and high-rise area and high-rise area, the pith of buildings are wide, so the airflow is smooth, so it is judged that the temperature is relatively low.
In this study, measurement errors of the X and Y axes were verified by using an 80-100 mm gauge block, an NPL type angle measuring device, and a spelling on a contact-type 3D measuring device surface plate. In addition, the measurement specimen was repeatedly measured 10 times at 10° intervals from 0° to 40° to confirm the average value and standard deviation. After confirming the statistical test value (P) through ANOVA analysis of the statistical program, the correlation between angle change and error was confirmed.
Noise is a sound that humans do not want. In this study, noise is measured for C172, the most frequently used general aviation trainer in Korea and abroad. In addition, in this study, noise measurement points are selected for Muan Airport, where most of the domestic training aircraft fly under the supervision of the Ministry of Land, Infrastructure and Transport. Based on this, the measured data is scaled and analyzed. In addition, we intend to analyze what characteristics C172 aircraft have unique through frequency analysis of noise of C172. Through this, it is intended to understand what type of noise training aircraft affect in future studies.