• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.302-315
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• 2021

In this study, factors such as improvement of a fishing process and safety, reduction of the labor force and headcount and development of the automation technology for offshore (eel and crab) pot fishing vessels were analyzed. A questionnaire survey was conducted to analyze and select the key factors using independent/paired sample t-test and correlation analysis, and a living lab was operated with ship owners, skippers and experts to discuss practical needs of the site. From the result of questionnaire survey and field requirements, it was possible to understand the level of awareness of ship safety, general safety equipment, fishing work process and fishing safety equipment from the point of view of the field. In addition, there were differences in the measurement results of each items because the working environment and experience were different according to the position of the ship owner and the skipper. The results of the questionnaire survey and various perceptions of field stakeholders were reflected when analyzing the fishing system and fishing process to choose the development equipment applicable to the field. From the analysis results, the selected development equipment based on the fishing equipment and process currently in operation are pot washing device, catch separation and fish hold injection device, length limit regulations and bait ejection device after use, automatic main line winding device, bait crusher, automatic (crab) pot hauling separator and so on.

• The Journal of Advanced Prosthodontics
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• v.13 no.4
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• pp.191-204
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• 2021

PURPOSE. The purpose of this study is to present a methodology to evaluate the accuracy of intraoral scanners (IOS) used in vivo. MATERIALS AND METHODS. A specific feature-based gauge was designed, manufactured, and measured in a coordinate measuring machine (CMM), obtaining reference distances and angles. Then, 10 scans were taken by an IOS with the gauge in the patient's mouth and from the obtained stereolithography (STL) files, a total of 40 distances and 150 angles were measured and compared with the gauge's reference values. In order to provide a comparison, there were defined distance and angle groups in accordance with the increasing scanning area: from a short span area to a complete-arch scanning extension. Data was analyzed using software for statistical analysis. RESULTS. Deviations in measured distances showed that accuracy worsened as the scanning area increased: trueness varied from 0.018 ± 0.021 mm in a distance equivalent to the space spanning a four-unit bridge to 0.106 ± 0.08 mm in a space equivalent to a complete arch. Precision ranged from 0.015 ± 0.03 mm to 0.077 ± 0.073 mm in the same two areas. When analyzing angles, deviations did not show such a worsening pattern. In addition, deviations in angle measurement values were low and there were no calculated significant differences among angle groups. CONCLUSION. Currently, there is no standardized procedure to assess the accuracy of IOS in vivo, and the results show that the proposed methodology can contribute to this purpose. The deviations measured in the study show a worsening accuracy when increasing the length of the scanning area.

• Fashion & Textile Research Journal
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• v.23 no.2
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• pp.226-236
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• 2021

The purpose of this study was to classify the torso shape based on abdominal protrusion caused by changes in the physical characteristics of middle-aged women. This study analyzed 3D shape data of 401 females ranging in age from 40 to 59 years who participated in the 6th Size Korea project. Based on the Size Korea 3D measurement standard, 27 additional items such as height, protrusion, and angle were measured in the 3D scan data. Nine factors were extracted from the analysis of constituent factors of the torso: "vertical size of torso," "flatness and protrusion of abdomen," "torso front extrusion," "upper body height," "bust size and flatness," "size of belly and angle of lower abdomen," "hip length," "hip flatness," and "horizontal size of bust." As a result of the cluster analysis using these nine factors, the torsos of middle-aged women were classified into three types. Type 1 has upper abdominal deposition with a small and long upper body and an advanced abdomen; type 2 has lower abdominal deposition with a small and short torso and a small belly and hip flexion; and type 3 has central abdominal deposition with a big and long torso, large breasts, and protruding abdo¬men front. The middle-aged women were mostly distributed in Type 2. The above results will be useful as basic data for the development of clothing with improved fit to accommodate the changed physical characteristics of middle-aged women.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.4
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• pp.35-40
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• 2022

This paper proposes an antenna that is located outside the PCB substrate of an electronic product to enable wireless communication in the ISM band. The PCB designed the T-shaped OPEN-STUB power supply line to be miniaturized so that it does not interfere with parts or interfere with design. The characteristics of the antenna were confirmed in the 2.4GHz and 5.8GHz bands using a T-shaped stub feeder and a spiral structure. The size of the antenna is 5mm in width × 6.5mm in length, and the thickness of the PCB is 1.2T. As a result of measurement of the manufactured antenna, it was possible to obtain a return loss of -10dB or more at 2.4GHz and 5.8GHz. In the E-plane, the gain was -4.45 dBi, and in the H-plane, the gain was -1.05 dBi. Therefore, the proposed small antenna for wireless communication showed excellent performance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.1
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• pp.121-126
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• 2022

This study is about an antenna implemented in the form of a monopole having a hexagonal symmetric pattern by simplifying the modified Hilbert curve fractal monopole structure. The modified Hilbert curve fractal monopole structure was simplified and miniaturized, and the radiator was implemented in a hexagonal symmetrical pattern to improve performance. The dielectric constant of substrate is 4.7, and the total line length with a meander-shaped symmetrical structure is 59 mm. The size of the antenna is 10 mm × 10 mm × 0.8 mm, and the line width is 0.4 mm. The size of the antenna measuring jig is 64 mm × 21 mm × 1 mm. The resonant frequency is 1.57 GHz, and the frequency range is 1.51 to 1.615 GHz. The frequency bandwidth is 105 MHz. As for the antenna gain, the measurement gain of the YZ-plane was 2.32 dBi, and that of the XZ-plane was -1.03 dBi. As a result, we confirmed that antenna miniaturization is possible using a hexagonal symmetric pattern fractal structure. In addition, we confirmed that the antenna performance can be easily improved by changing the structure of the radiator.

• Fashion & Textile Research Journal
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• v.24 no.1
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• pp.146-155
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• 2022

We proposed a simple process of creating electroconductive textiles by using PEDOT:PSS(Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate))/non-oxidized graphene to coat polyamide or polyurethane knitted fabric for smart healthcare purposes. Electroconductive textiles were obtained through a coating process that used different amounts of PEDOT:PSS/non-oxidized graphene solutions on polyamide/polyurethane knitted fabric. Subsequently, the surface, electrical, chemical, weight change, and elongation properties were evaluated according to the ratio of PEDOT:PSS/non-oxidized graphene composite(1.3 wt%:1.0 wt%; 1.3 wt%:0.6 wt%; 1.3 wt%:0.3 wt%) and the number of applications(once, twice, or thrice). The specimens' surface morphology was observed by FE-SEM. Further, their chemical structures were characterized using FTIR and Raman spectroscopy. The electrical properties measurement (sheet resistance) of the specimens, which was conducted by four-point contacts, shows the increase in conductivity with non-oxidized graphene and the number of applications in the composite system. Moreover, a test of the fabrics' mechanical properties shows that PEDOT:PSS/non-oxidized graphene-treated fabrics exhibited less elongation and better ability to recover their original length than untreated samples. Furthermore, the PEDOT:PSS/non-oxidized graphene polyamide/polyurethane knitted fabric was tested by performing tensile operations 1,000 times with a tensile strength of 20%; Consequently, sensors maintained a constant resistance without noticeable damage. This indicates that PEDOT:PSS/non-oxidized graphene strain sensors have sufficient durability and conductivity to be used as smart wearable devices.

• Wind and Structures
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• v.34 no.4
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• pp.355-369
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• 2022

Section model test, as the most commonly used method to evaluate the aerostatic and aeroelastic performances of long-span bridges, may be carried out under different conditions of incoming wind speed, geometric scale and wind tunnel facilities, which may lead to potential Reynolds number (Re) effect, model scaling effect and wind tunnel scale effect, respectively. The Re effect and scale effect on aerostatic force coefficients and aeroelastic characteristics of streamlined bridge decks were investigated via 1:100 and 1:60 scale section model tests. The influence of auxiliary facilities was further investigated by comparative tests between a bare deck section and the deck section with auxiliary facilities. The force measurement results over a Re region from about 1×10⁵ to 4×10⁵ indicate that the drag coefficients of both deck sections show obvious Re effect, while the pitching moment coefficients have weak Re dependence. The lift coefficients of the smaller scale models have more significant Re effect. Comparative tests of different scale models under the same Re number indicate that the static force coefficients have obvious scale effect, which is even more prominent than the Re effect. Additionally, the scale effect induced by lower model length to wind tunnel height ratio may produce static force coefficients with smaller absolute values, which may be less conservative for structural design. The results with respect to flutter stability indicate that the aerodynamic-damping-related flutter derivatives 𝘈^*₂ and 𝐴^*₁𝐻^*₃ have opposite scale effect, which makes the overall scale effect on critical flutter wind speed greatly weakened. The most significant scale effect on critical flutter wind speed occurs at +3° wind angle of attack, which makes the small-scale section models give conservative predictions.

• The Journal of the Acoustical Society of Korea
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• v.42 no.1
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• pp.57-66
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• 2023

In this paper, it was investigated how the amount of energy harvesting will be varied from the FTEH which has inlet area is wider than outer area and attaching cantilever type MFC (Macro Fiber Composite) using by theoretical and experimental approaches. When MFC length increased 50 % vibration displacement also increased 3.5 times. When thickness decreased vibration displacement increased 30.9 times. In underwater tank experiments FTEH with spiral screw, flexible support, vertical direction fabrication cases showed maximum energy harvesting more 5 times than the case of MFC installed horizontally without spiral screws and on rigid supports. When the flow speed of 0.24 m/s FTEH's optimal resistance applied 4,10 kΩ, energy storage in the capacitor was measured 4 ㎼·s during 350 seconds. It was confirmed that the charging energy can be increased by lengthening the capacitor charging time of the large-area MFC installed vertically on the flexible support at high flow speed.

• Journal of Veterinary Clinics
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• v.40 no.2
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• pp.119-123
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• 2023

Although various imaging evaluation methods have been developed and utilized, thoracic radiography remains essential and is the top priority for diagnosing and managing cardiac diseases. Thoracic radiographic measurements associated with the vertebral heart scale (VHS) and caudal vena cava (CVC) can objectively diagnose cardiac disease in many animals. In particular, VHS measurement is primarily used to evaluate the dimensions of the heart size on thoracic radiographs and can measure cardiomegaly more objectively. Additionally, the value of the CVC compared with the aorta (Ao) and the length of vertebrae (VL) can be used as valuable parameters in right congestive heart failure. To describe the CVC/Ao and CVC/VL ratios in 10 long-tailed gorals (Naemorhedus caudatus) without subjective radiographic evidence of cardiac diseases. The VHS, CVC, Ao, and VL of gorals were measured in the right lateral (RL) view of the thoracic radiographs. In the RL view of 10 gorals, the VHS was 9.31 ± 0.55 vertebrae (v), the CVC/Ao ratio was 0.84 ± 0.13, and the CVC/VL ratio was 0.67 ± 0.09. Additionally, the thoracic morphology of gorals was determined to be intermediate (thoracic depth-to-width ratio, 1.04 ± 0.09, 0.75-1.25). This study confirmed that VHS was significantly correlated with CVC and Ao, and measuring and comparing each value would help diagnose cardiac diseases in gorals. The radiographic measurements in this study will allow veterinarians to diagnose several cardiac diseases in gorals.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.95-101
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• 2022

Microfluidic radioimmunoassay (RIA) platform called µ-RIA spends less reagent and shorter reaction time for the analysis compared to the conventional tube-based radioimmunoassay. This study reported the design of µ-RIA chips optimized for the gamma counter which could measure the small samples of radioactive materials automatically. Compared with the previous study, the µ-RIA chips developed in this study were designed to be compatible with conventional RIA test tubes. And, the automatic gamma counter could detect radioactivity from the ¹²⁵I labeled anti-PSA attached to the chips. Effects of the multi-layer microchannels and two-phase flow in the µ-RIA chips were investigated in this study. The measured radioactivity from the ¹²⁵I labeled anti-PSA was linearly proportional to the number of stacked chips, representing that the radioactivity in µ-RIA platform could be amplified by designing the chips with multi-layers. In addition, we designed µ-RIA chip to generate liquid-gas plug flow inside the microfluidic channel. The plug flow can promote binding of the biomolecules onto the microfluidic channel surface with recirculation in the liquid phase. The ratio of liquid slug and air slug length was 1 : 1 when the ¹²⁵I labeled anti-PSA and the air were injected at 1 and 35 µL/min, respectively, exhibiting 1.6 times higher biomolecule attachment compared to the microfluidic chip without the air injection. This experimental result indicated that the biomolecular reaction was improved by generating liquid-gas slugs inside the microfluidic channel. In this study, we presented a novel µ-RIA chips that is compatible with the conventional gamma counter with automated sampler. Therefore, high-throughput radioimmunoassay can be carried out by the automatic measurement of radioactivity with reduced radiowaste generation. We expect the µ-RIA platform can successfully replace conventional tube-based radioimmunoassay in the future.