• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.73-83
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• 2022

The purpose of this paper was to identify a method to improve received noise in a specific frequency band, caused by RF radiation signals during aircraft operation. The communication equipment of the aircraft is critical to the performance and safety of the flight mission, as it is responsible for the function of internal and external communications. Noise-free, clean communication quality, as well as transmission and receiving functions have to be implemented. Thus, the cause analysis of the reception noise in a specific frequency band, was analyzed through trouble shooting. The receiving noise due to the RF radiation signal emitted from the subsystem unit inside the aircraft, was improved by shielding with a CAP with electroless nickel plating applied. Additionally, the measurement and verification results of the improvement method are also described.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.2
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• pp.163-171
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• 2022

Objectives: Fit performance may vary depending on the ambient aerosol number and ratio in respective test environment. Although several instrument can measure it, they differ with respect to the measurement principle and the range of ambient aerosols collected to calculate the fit factor. Methods: In this study, the fit performance between a condensation nuclei counter(CNC) and an optical particle counter(OPC) was compared according to ambient aerosol number concentration, and evaluated consistency. One type respirators(N95 masks) was worn by 50 participants PortaCount®(Pro+ 8038) and MT®(05U) were connected with one probe to one mask, and Fit Factors(FFs) were measured simultaneously. Results: The interclass correlation coefficient of the fit factor and ambient aerosol number, as measured by the two instrument, was 0.82 and 0.79, respectively, indicating a high consistency level. On the other hand there was a significant correlation between the successful test performance of the OPC instrument and the ambient aerosol number. Conclusions: The test was passed with the CNC and OPC instruments when the ambient aerosol number was 635-3,332 particles/cm³ and 368-1,976 particles/cm³, respectively. Thus, the ideal ambient aerosol number of particles differed between the two instrument.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.1-6
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• 2021

In this study, we developed AMI terminals of 1 (reader): N (small transmitter). Currently, the government is focusing on the Gas AMI demonstration project to advance the outdated metering system of the urban gas industry, led by the government-sponsored ministries. The supply of gas AMI meters has the advantage of resolving uncertainties in privacy violations and measurement information and preparing for consumer safety through gas leakage detection. In the case of existing AMI meters, readers and transmitters were 1:1 methods, while this technology can be extended to multiple generations with a 1:N method, and a technology that can extend battery life by implementing a low-power design is applied. We hope that this research will contribute to the gas AMI supply project in the future.

• Journal of the FoodService Safety
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• v.2 no.1
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• pp.44-50
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• 2021

Physicochemical and antioxidant properties of the three different calorie types of HMR curry rice using fermented turmeric were analyzed in this study. The general tumeric added sample groups showed significantly higher carbohydrate content than the fermented turmeric sample group. In all sample groups, the ratio of protein, fat, and carbohydrate was found to be appropriate according to the nutritional composition ratio as one meal recommended by the Ministry of Health and Welfare. The brightness L value of the general turmeric-added sample group was measured to be significantly brighter than the fermented turmeric-added sample group. The fermented turmeric sample group showed a slightly lower pH value than the general sample group due to organic acids generated during fermentation. As a result of analyzing the radical scavenging activity of ABTS, LFTC, MFTC, and HFTC of the fermented turmeric group were 40.20, 40.46, and 36.16%, respectively, compared to those 32.41, 37.75, and 36.16% of LNTC, MNTC and FNTC of the general sample groups, respectively, consistently indicating that more free radicals were generated in the fermented sample group (p<0.01). Relatively unstable to heat and acid, DPPH scavenged radicals showed similar results to those of ABTS radical scavenging activity in terms of activity. Similar results were also shown in the measurement of total flavonoid and phenol content, which are known to have antioxidant antiviral and anticancer effects. Thus we could conclude that pilot products of the high quality varied calorie levels of HMR Bibimbap set with tumeric, which is helpful for antioxidant action have been developed to meet various customer needs.

• Journal of Fashion Business
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• v.26 no.5
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• pp.91-104
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• 2022

In this study, a cycling smart wear for measuring cycling posture and motion was developed using a three-dimensional motion analysis camera and an IMU inertial sensor. Results were compared according to parts to derive the optimal smart device attachment location, enabling correct posture measurement and cycle motion analysis to design a pattern. Conclusions were as follows: 1) 'S-T8' > 'S-T10' > 'S-L4' was the most significant area for each lumbar spine using a 3D motion analysis system with representative posture change (90°, 60°, 30°) to derive incisions and size specifications; 2) the part with the smallest relative angle change among significant section reference points during pattern design was applied as a reference point for attaching a cycling smart device to secure detachable safety of the device. Optimal locations for attaching the cycling device were the "S-L4" hip bone (Sacrum) and lumbar spine No. 4 (Lumbar 4^th); 3) the most suitable sensor attachment location for monitoring knee induction-abduction was the anatomical location of the rectus femoris; 4) a cycling smart wear pattern was developed without incision in the part where the sensor and electrode passed. The wearing was confirmed with 3D CLO. This study aims to provide basic research on exercise analysis smart wear, to expand the smart cycling area that could only be realized with smart devices and smart watches attached to current cycles, and to provide an opportunity to commercialize it as cycling smart wear.

• Journal of the Korea Institute of Building Construction
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• v.22 no.2
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• pp.171-182
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• 2022

The regular assessment of a building is important to understand structural safety and latent risk in the early stages of building life cycle. However, methods of traditional assessment are subjective, atypical, labor-intensive, and time-consuming and as such the reliability of these results has been questioned. This study proposed a method to bring accurate results using a 3D laser scanner and integrate them in Building Information Modeling (BIM) to visualize defective condition. The specific process for this study was as follows: (1) semi-automated data acquisition using 3D laser scanner and python script, (2) scan-to-BIM process, (3) integrating and visualizing defective conditions data using dynamo. The method proposed in this study improved efficiency and productivity in a building assessment through omitting the additional process of measurement and documentation. The visualized 3D model allows building facility managers to make more effective decisions. Ultimately, this is expected to improve the efficiency of building maintenance works.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.9
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• pp.1357-1366
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• 2022

It is important to quickly and accurately build a disaster network or tactical mobile communication network adapting to the field. In configuring the traditional wireless communication systems, the parameters of the base station are set through cell planning. However, for cell planning, information on the environment must be established in advance. If parameters which are not appropriate for the field are used, because they are not reflected in cell planning, additional optimization must be carried out to solve problems and improve performance after network construction. In this paper, we present a rapid mobile communication network construction and optimization method using artificial intelligence and SON technologies in mobile communication base stations. After automatically setting the base station parameters using the CNN model that classifies the terrain with path loss prediction through the DNN model from the location of the base station and the measurement information, the path loss model enables continuous overage/capacity optimization.

• Journal of Space Technology and Applications
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• v.2 no.3
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• pp.221-229
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• 2022

This paper reports on the design and installation of a thermostat to keep the temperature of the fluxgate magnetometer constant and the data stability evaluation after installation. The thermostat was installed at the Icheon Geomagnetic Observatory operated by the Korean Space Weather Center of National Radio Research Agency. It was designed in consideration of stability of temperature control against safety incident, potential effects on magnetic field measurement, and the temperature control efficiency. After the temperature control device was installed, it was confirmed that the temperature was constantly maintained at the level of 20℃. Delta F and baseline values were used to evaluate geomagnetic data stability, and it was confirmed that delta F and baseline fluctuations were reduced after installation of the thermostat.

• The Korean Journal of Pain
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• v.36 no.1
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• pp.98-105
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• 2023

Background: Ultrasound-guided first sacral transforaminal epidural steroid injection (S1 TFESI) is a useful and easily applicable alternative to fluoroscopy or computed tomography (CT) in lumbosacral radiculopathy. When a needle approach is used, poor visualization of the needle tip reduces the accuracy of the procedure, increasing its difficulty. This study aimed to improve ultrasound-guided S1 TFESI by evaluating radiological S1 posterior foramen data obtained using three-dimensional CT (3D-CT). Methods: Axial 3D-CT images of the pelvis were retrospectively analyzed. The radiological measurements obtained from the images included 1st posterior sacral foramen depth (S1D, mm), 1st posterior sacral foramen width (S1W, mm), the angle of the 1st posterior sacral foramen (S1A, °), and 1st posterior sacral foramen distance (S1ds, mm). The relationship between the demographic factors and measured values were then analyzed. Results: A total of 632 patients (287 male and 345 female) were examined. The mean S1D values for males and females were 11.9 ± 1.9 mm and 10.6 ± 1.8 mm, respectively (P < 0.001); the mean S1A 28.2 ± 4.8° and 30.1 ± 4.9°, respectively (P < 0.001); and the mean S1ds, 24.1 ± 2.9 mm and 22.9 ± 2.6 mm, respectively (P < 0.001); however, the mean S1W values were not significantly different. Height was the only significant predictor of S1D (β = 0.318, P = 0.004). Conclusions: Ultrasound-guided S1 TFESI performance and safety may be improved with adjustment of needle insertion depth congruent with the patient's height.

• Journal of Korean Society for Quality Management
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• v.51 no.1
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• pp.131-154
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• 2023

Purpose: The purpose of this paper is to design an integrated informatization system that can manage quality & KPI by integrating management systems in the aerospace and defense industry, and study the effect on KPI when applied to related companies. Methods: The 7 management systems required for integration in the AS&D industry were studied, and an empirical analysis was conducted for H company in South Korea for the application of e-QMS integrated informatization & KPI system based on security environment and open quality. Results: The results of this study were analyzed to have an effect on the improvement of customer satisfaction and the positive improvement of quality failure cost in the aerospace and defense industry. And it was analyzed that it works to continuously comply with ethical management and environmental laws and prevent safety accidents. Conclusion: The greatest significance of this study is that it attempted to build an e-QMS integrated system in the aerospace and defense industry. Considering that the case of integrated management system and integrated operation of KPI in related industries has not been introduced in the existing literature, the results of this study will be shared as a meaningful preceding study in the era of digital quality information. In addition, the fact that the open-quality quality innovation methodology emphasizing measurement(M), tracking(T), and connection(C) was actually applied in an AS&D company and its effectiveness was objectively proven. It is expected that it will be a good paper for follow-up research.