PURPOSES : This study investigates the effects of three different three-color arrow traffic light operations on right-turn vehicles at intersections in Busan Metropolitan City. METHODS : Intersections in this study were categorized as general intersections (Type 1), intersections with right-turn pockets (Type 2), and intersections with scramble crosswalks (Type 3), and were investigated in terms of the efficiency (i.e., control delay) and safety (i.e., number of conflicts) of right-turn vehicles by employing VISSIM 2023 and SSAM3. RESULTS : From a mobility perspective (i.e., control delay), the protected/permitted operation outperformed the other two methods at the three types of intersections. The protected operation, similar to the results of the protected/permitted operation, was also superior to the permitted operation in terms of safety (i.e., number of conflicts). CONCLUSIONS : Protected/permitted operation has been proven to be a more efficient and safer measure than other operation methods for alleviating the problems of protected right-turn operation, which is currently implemented without three-color arrow traffic lights.

PURPOSES : This study develops a model that can estimate travel speed of each movement flow using deep-learning-based probe vehicles at urban intersections. METHODS : Current technologies cannot determine average travel speeds for all vehicles passing through a specific real-world area under obseravation. A virtual simulation environment was established to collect information on all vehicles. A model estimate turning speeds was developed by deep learning using probe vehicles sampled during information processing time. The speed estimation model was divided into straight and left-turn models, developed as fully-offset, non-offset, and integrated models. RESULTS : For fully-offset models, speed estimation for both straight and left-turn models achieved MAPE within 10%. For non-offset models, straight models using data drawn from four or more probe vehicles achieved a MAPE of less than 15%. The MAPE for left turns was approximately 20%. CONCLUSIONS : Using probe-vehicle data(PVD), a deep learning model was developed to estimate speeds each movement flow. This, confirmed the viability of real-time signal control information processing using a small number of probe vehicles.

Fluorine-doped tin oxide (FTO) has been used as a representative transparent conductive oxide (TCO) in various optoelectronic applications, including light emitting diodes, solar cells, photo-detectors, and electrochromic devices. The FTO plays an important role in providing electron transfer between active layers and external circuits while maintaining high transmittance in the devices. Herein, we report the effects of substrate rotation speed on the electrical and optical properties of FTO films during ultrasonic spray pyrolysis deposition (USPD). The substrate rotation speeds were adjusted to 2, 6, 10, and 14 rpm. As the substrate rotation speed increased from 2 to 14 rpm, the FTO films exhibited different film morphologies, including crystallite size, surface roughness, crystal texture, and film thickness. This FTO film engineering can be attributed to the variable nucleation and growth behaviors of FTO crystallites according to substrate rotation speeds during USPD. Among the FTO films with different substrate rotation speeds, the FTO film fabricated at 6 rpm showed the best optimized TCO characteristics when considering both electrical (sheet resistance of 13.73 Ω/□) and optical (average transmittance of 86.76 % at 400~700 nm) properties with a figure of merit (0.018 Ω-1).

In this study, Pleurotus ostreatus No.42 was cultured in glucose-peptone-yeast-wheat bran medium using a previously reported novel rotary draft tube bioreactor. Versatile peroxidase (VP), a lignin-degrading enzyme, was isolated from a pellet-type mycelium culture grown in the medium for seven days. The VP was purified by sequentially applying ultra-filtration, DEAESepharose CL-6B column, and Mono Q column. SDS-PAGE analysis revealed the molecular weight of VP to be 36.4 KDa with an isoelectric point of 3.65. The amino acid sequence was confirmed as VTCATGQTT. The purified VP was observed to possess the property of not only oxidizing Mn ions but also decomposing veratryl alcohol, a non-phenolic compound. The catalytic ability of VP is a subject for future research.

The EV electric vehicle market is growing rapidly worldwide. Magnet fixing technology is important for mass production of driving motors, a key part of electric vehicles. The magnet fixing method was carried out by the PAM (Polyamide molding) method. This study conducted the injection of rotor core magnet PA of EV traction motor and is a study on the amount of rotor core deformation. In this study, the change in the outer diameter of the product after injection and the non-molding phenomenon were tested. An injection mold was made and the results and phenomena of product deformation types are discussed.

Prepreg is an abbreviation of Preimpregnated Materials. It is a sheet-type product in which a matrix is ​​impregnated with reinforced fiber. The prepreg has very different properties depending on the orientation of the fibers and the weaving method, and the orientation of the fibers plays an important role in determining the mechanical strength of CFRP. Short and randomly oriented reinforcing fibers show isotropy, while long, unidirectional reinforcing fibers exhibit anisotropic behavior and are strongest when the applied load is parallel to the reinforcing fibers. Classification by the direction of the fiber is divided into unidirectional, orthogonal, multiaxial, and the like. Uni-directional refers to a state in which almost all fibers in the fabric are aligned in one direction. When the fibers used as reinforcing materials are aligned in one direction, the fibers are used in a straight line without twisting during the fabric production process, and there is an advantage in that the amount of fibers used as a whole can be minimized. A uni-directional prepreg exhibits different cutting forces depending on the stacking orientation angle. In this experiment, the optimal cutting conditions for a uni-directional prepreg 45 degree orientation angle specimen are presented.

The objective of this study is to analyze the difference between the theoretically calculated torque values of lead screws used in vehicle seat rails and the required torque values due to various disturbances that occur in actual systems. Lead screws were classified into square and trapezoidal threads and modeled by two lead type. Dynamic analysis models were constructed by applying contact conditions and rotational joints between the lead screw and nut. The validity of the dynamic model was verified by comparing the torque values obtained from rigid body dynamic analysis with the theoretically calculated torque values. Then, the lead screw was modeled as a flexible body to investigate the torque variation required for the lead screw when dynamic loads are considered. This study will help predict the actual torque values of lead screws for seat rails.

In the era of the 4th Industrial Revolution, Logistic 4.0 using data-based technologies such as IoT, Bigdata, and AI is a keystone to logistics intelligence. In particular, the AI technology such as prognostics and health management for the maintenance of logistics facilities is being in the spotlight. In order to ensure the reliability of the facilities, Time-Based Maintenance (TBM) can be performed in every certain period of time, but this causes excessive maintenance costs and has limitations in preventing sudden failures and accidents. On the other hand, the predictive maintenance using AI fault diagnosis model can do not only overcome the limitation of TBM by automatically detecting abnormalities in logistics facilities, but also offer more advantages by predicting future failures and allowing proactive measures to ensure stable and reliable system management. In order to train and predict with AI machine learning model, data needs to be collected, processed, and analyzed. In this study, we have develop a system that utilizes an AI detection model that can detect abnormalities of logistics rotational equipment and diagnose their fault types. In the discussion, we will explain the entire experimental processes : experimental design, data collection procedure, signal processing methods, feature analysis methods, and the model development.

PURPOSES : This study aims to evaluate the traffic safety by collecting and analyzing vehicle speed and conflict frequency data based on the provision of information to vehicle drivers and crosswalk pedestrians under right-turn conditions. METHODS : Two evaluation scales, namely speed of access and number of conflicts, were used to quantitatively evaluate the effects of the new information provision method. Data on access speed and the number of conflicts according to information provision were collected and compared before and after information provision. RESULTS : Analysis of the pre- and post-spot speed reduction rates revealed an overall reduction rate of 32.6%. The conflict ratio was 81.0% before information provision but increased to 83.3% after information provision. CONCLUSIONS : When LED display information was provided, the effect of decelerating the approaching speed of vehicles in the rightturn torpedo section was statistically significant, but the reduction in the conflict ratio was not. Factors such as intersection status, traffic volume and vehicle speed, affect the approach speed and increase or decrease the number of conflicts. Regardless of whether information is provided, the average compliance rate of the Road Traffic Act when turning right in the channelization area is 16.7%, which is significantly different from the average compliance rate of 48.4% immediately after the Road Traffic Act was revised in July 2022.

In the anchovy boat seine fishing boat, it is necessary to select other aquatic organisms other than live anchovies, which are the target species of catch. By making a rotating roller sorter using hydraulic pressure, the anchovy sorting amount was compared and the sorting accuracy of the rotary roller sorter, and the discharge speed of butter fish and jerry fish according to the number of roller revolutions were analyzed. The rotating roller sorter increases the weight of the sorted raw anchovy by 54%, 74% and 91.5% compared to the round bar fixed type, so it can reduce the required time by an average of 73.2%. As a result of converting the sorting accuracy to the weight of pure anchovies excluding the catch weight, the round bar fixed type was 89%; however, the average of the rotating roller sorter was 97.7%. Thus, the sorting accuracy of the rotary roller sorter was further improved by about 8.7%. The roller speed moved 7% at 300 rpm, 7.5% at 600 rpm, and 16% at 900 rpm, so butter fish were discharged overboard 10% faster than jelly fish on average. In addition, the average feed speed of butter fish and jelly fish is 1,400 mm/s when the roller rotation speed is 300 rpm, 1,480 mm/s at 600 rpm, and 1,850 mm/s at 900 rpm. A Φ58 mm roller rotates once it moved about 1.23 mm. In the future, a follow-up study of quantitative evaluation is needed targeting more non-target fish species of anchovy boat seine.

This study investigated the rocking behavior of unreinforced masonry walls and wall piers under cyclic loading. Based on the benchmark tests, the characteristics of load-deformation relations in masonry walls with rocking failure were captured, focusing on observed deformation modes. The rocking strengths of masonry walls (i.e., peak and residual strengths) were evaluated, and the effects of opening configurations on the masonry wall strength were examined. The deformation capacity of the rocking behavior and the hysteresis shape of the load-deformation relations were also identified. Based on the results, modeling approaches for the rocking behavior of masonry walls were discussed.

PURPOSES : The turning movement of vehicles is directly affected by such factors as vehicle length, wheelbase, steering angle, articulated angle, and wheel steering. Therefore, it is necessary to analyze the impact of changes in each factor on the turning of the vehicle. Because a vehicle with a long body, such as an articulated bus, makes a wide turn, this study analyzes the swept path of the driving vehicle considering the specifications of the vehicle. METHODS : This study was conducted by dividing driving routes into four routes of two-lane four-way roundabouts, and the turning conditions were examined for six types (Type 1–6) that simulated actual articulated bus data. The same vehicle specifications as those of the actual articulated bus were applied to the road design simulation (AutoTURN Pro), and the width of the swept path for the articulated bus was investigated based on the wheel steering control. Using a virtual reference line for dividing the inscribed circle into lanes of the roundabout by 5°, the driving width of the swept path was measured and the angle at which the driving width was largest during driving through the turning intersection was examined. In addition, the changes in the driving width of the swept path according to the wheel steering control under the same wheel turning conditions, as well as the articulated and steering angles, were investigated. RESULTS : The driving width of the swept path for the vehicle (Type 1) with the front wheel control function being an all-wheel system was less than that of an articulated bus with the largest driving width of 15° after entering the roundabout and 15° before entering the roundabout (Type 2). Furthermore, although the specifications of the vehicles were the same, it was determined that Type 5 was superior to Type 6 after reviewing the driving width in light of changes in the steering and articulated angles. CONCLUSIONS : The results of this study are expected to contribute to the field of road design considering traffic safety when large vehicles, such as articulated buses, turn on roundabouts or curved road sections.

본 연구의 목적은 국내 발레단 소속 여자 무용수를 대상으로 연속 회전점프 시 시각선택과 회전 순서에 따른 차이를 도약과 착지구간으로 분류하여 비교하였다. 10명의 대상자(연령: 26.0±2.9 yrs, 신장: 163.4±3.3 cm, 체중: 46.8±3.6 kg, 발레경력: 12.3±5.9 yrs)가 연구에 참여하였다. 3차원 동작분석기와 지면반력기를 이용하여 신체중심의 높이와 도약과 착지 시 지면반력을 측정하였다. 시각선택(양눈 사용, 왼 눈 사용, 오른눈 사용)과 회전순서(첫번째 회전점프, 두 번째 회전점프)에 따른 차이를 반복측정 이원변량 분석을 통하여 분석하였다. 신체중심의 높이는 첫 번째 회전점프가 높게 나타났다. 도약 시 지면반력의 좌 우힘은 좌우발 모두 두 번째 회전점프에서 왼발은 외측힘, 오른발은 내측힘이 강하게 나타났고, 전후힘은 오른발에서 첫 번째 회전점프 시 전방힘이 강하게 나타났으며, 수직힘은 좌우발 모두 차이가 없었다. 착지 시 전후힘은 왼발에서 두 번째 착지에서 후방힘이 강하게 나타났고, 오른발은 왼쪽 시각 사용에서 후방힘 이 강하게 나타났다. 수직힘은 왼발에서 두 번째 착지, 오른발은 첫 번째 착지에서 강하게 나타났다.

본 연구에서는 드론을 활용한 변위계측에서 드론의 회전진동 보정을 위해 드론 내부의 가속도계를 이용하는 방법 대신에 드 론 영상 내부의 변위가 발생하지 않는 고정점을 활용한 드론의 회전진동 보정방법을 제안하고자 한다. 영상 내부의 고정점을 활용한 드론 회전진동 보정을 위한 예비 연구로서, 카메라를 고정시킨 후 타겟을 회전하여 회전각도를 측정하는 실험과 회전하는 카메라를 통 해 변위가 발생하는 모형구조물의 변위를 계측하는 실험을 통해 카메라의 회전진동이 발생하는 경우 변위 계측정확도를 검증하였다. 변위가 3mm 이하로 발생 시 카메라 진동이 발생하였을 때 계측 신뢰도가 낮은 반면, 변위가 3mm를 초과하여 발생한 경우 비교적 정 확하게 계측되었다.

본 연구의 목적은 좌우 방향의 회전 후 직립자세 시 압력중심과 근전도 분석을 토대로 회전선호 도가 신체 안정성에 미치는 영향을 알아보고자 하였다. 연구의 대상은 오른쪽 손과 발의 편측선호도가 높 은 대상자 16명으로 3가지 회전방향 조건(QS: 직립자세, LT: 왼쪽 10바퀴, RT: 오른쪽 10바퀴)을 수행하 였다. 회전 후 직립자세 시 안정성을 평가하기 위하여 압력측정판과 근전도를 이용하여 결과를 도출하여 분석하였다. 연구결과로 모든 압력중심 변인은 QS보다 LT, RT가 크게 나타났지만, 회전방향에 따른 차이 는 보이지 않았다. 근전도 결과는 좌우 비복근에서 회전방향에 따라 RT가 QS보다 근활성도가 크게 발생 되었다. 결론적으로 대상자가 모두 오른쪽 측면선호도가 높았지만 압력중심에서는 회전선호도의 영향이 없 었고, 비복근에서는 회전선호도의 영향이 나타났다.

본 논문에서는 1차원 오일러 보 요소(Euler-Bernoulli Beam Element)를 이용한 회전익기 축계에 대한 중량 최적설계를 수행하였다. 회전 축계의 특성을 고려해 비틀림(Torsion)과 베어링과 같은 축지지 강성 및 플랜지(Flange) 질량을 모두 고려하였고, 동적 안전성 확 보를 위해 고유치 해석을 수행하여 임계속도(Critical Speed)와 기어박스로부터 오는 치 변형 가진을 회피할 수 있도록 하였다. 축의 길 이는 고정된 상태에서 두께와 반경을 조절하여 중량 최적화를 수행하였으며, 최적화 과정은 2단계로 나누어 진행하였다. 1단계에서 는 비틀림 강도를 제약조건으로 하여 중량을 최적화한 후 2단계에서는 축계 안정성 확보 기준(Headquarters, U.S. Army Material Command, 1974)에 따라 축의 비틀림 강도에 대한 제약조건을 만족시키며, 축의 1차 모드가 임계속도를 회피할 수 있도록 축 1차모드 와 임계속도의 차이가 최대가 되도록 최적화를 진행하였다. 주어진 1차원 보 요소를 이용하여 최적설계를 한 결과를 3차원 유한요소 모델과 실제 제작된 축게의 시험결과와 비교하여 제안된 방법을 검증하였다.