• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.81-86
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• 2017

The high-pressure resin transfer molding (HP-RTM) process has a very effective for the mass production of carbon fiber reinforced plastic (CFRP) for light weight in the automotive industry. In developing robust equipment, new process and fast cure matrix systems reduces significantly the cycle time less than 5 minutes in recent years. This paper describes the cavity pressure, temperature and molding characteristics of the HP-RTM process. The HP-RTM mold was equipped with two cavity pressure sensors and three temperature sensors. The cavity pressure characteristics of the HP-RTM injection, pressurization, and curing processes were studied. This experiment was conducted with selected process parameters such as mold cap size, maximum press force, and injection volume. Consequently, this monitoring method provides correlations between the selected process parameters and final forming characteristics in this work.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.1
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• pp.161-166
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• 2012

Intravenous (IV) injection is widely used to supply Ringer solution directly into a vein in hospital. Generally, a passive injection method has been used, which causes the inconsistent flow rate of fluid and inappropriate control of injection time by a patient. It leads to an unnecessary nurse's overwork and decrement of IV injection's effect. To solve these problems, flow control infusion pumps have been developed. But because of relatively heavy weight and high price, its usage has been limited. In the present study, a new automatic IV injection system is developed. It is installed with a small pressing mechanism driven by a small electric motor to regulate the flow rate by pressing tube. Proportional integral derivative (PID) feedback control algorithm is applied to control the electric motor. The system is smaller in size and uses lower power than the existing commercial product. The newly developed system is also installed with networking capability, which enables monitoring the status of several automatic IV injection system at the same time.

• Journal of the Korean Society of Safety
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• v.16 no.2
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• pp.80-84
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• 2001

Work stress and health are very important factors related to workers' condition and work safety, Author has conducted a couple of tests to check up three people's pulses before they work during their work for three types of safety guard in construction site. Work type, age, weight, sex experience year, ambient temperature n recorded as variables in this study. These are checked and asked by the author directly, before their pulse check Also, workers' Pulses were measured at height H-0 and H-9.0m to understand psychological the degree of psychological nervousness degree. POLAR protrainer NVTM HRM system(wrist recorder and sensor) was used for the site test. There are three(3) different types of construction safety guard which have been used for, this study. They are usually or frequently used and found in the site. Four different ranges of age groups(20's, 30's 40's, 50's) carpenters are assisted to the test sites with wearing pulse recorder and sensor respectively. All three types of safety guards have the same height 90㎝ even though they are different types. On top of five(5) stories tublar framed scaffolding is fabricated, similar to the one in site, where those safety guards are installed. The older(=more experienced) the workers are the more stable they are. it is shown. Also, It is verified the visually uncomfortable rail type can cause workers to psychologically be unstable.

• Journal of Sensor Science and Technology
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• v.25 no.6
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• pp.431-434
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• 2016

Currently, the radial basis function network (RBFN) and various other neural networks are employed to classify gases using chemical sensors arrays, and their performance is steadily improving. In particular, the identification performance of the RBFN algorithm is being improved by optimizing parameters such as the center, width, and weight, and improved algorithms such as the radial basis function network-stochastic gradient (RBFN-SG) and radial basis function network-normalized stochastic gradient (RBFN-NSG) have been announced. In this study, we optimized the number of centers, which is one of the parameters of the RBFN-NSG algorithm, and observed the change in the identification performance. For the experiment, repeated measurement data of 8 samples were used, and the elbow method was applied to determine the optimal number of centers for each sample of input data. The experiment was carried out in two cases(the only one center per sample and the optimal number of centers obtained by elbow method), and the experimental results were compared using the mean square error (MSE). From the results of the experiments, we observed that the case having an optimal number of centers, obtained using the elbow method, showed a better identification performance than that without any optimization.

• Korean Journal of Artificial Intelligence
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• v.8 no.2
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• pp.1-5
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• 2020

Children's home accidents are less common than in the past. However, safety accidents continue to occur due to carelessness of the parents. To solve the problem, there are fall prevention screens that can withstand the weight of children, and safety railings that can be adjusted directly to solve the problem. However, these have disadvantages such as stability, convenience, and damage to the landscape. In this paper, we developed an automatic safety accident prevention fence system that can be installed on a window using Arduino, eliminating the disadvantages of previous safety accident prevention products. This system measures the height of a person standing in front of the fence and the distance between the person and the fence with two infrared sensors and moves automatically using a motor. In addition, in accordance with the U-Healthcare society, users can check the temperature, humidity, and fine dust concentration of the external environment through mobile. Each information can be obtained through DHT 11 sensor, fine dust concentration sensor, and Bluetooth connected toArduino. These can help the user's health care.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.2
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• pp.53-59
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• 2022

In this paper, a mobile robot capable of remote control is designed in consideration of the user's various work environments. Specifically, a mobile remote work robot that moves in a predetermined direction and can perform a series of tasks in synchronization with the user's hand movements, and a control system and control method for controlling the robot were proposed. It was implemented using a robot hand and a wheel for movement to assist in tasks such as transporting dangerous goods or heavy goods. In order to evaluate the performance of the developed robot, the maximum weight that can be carried by the robot hand and the movable inclination of the robot were tested, and the test evaluation results satisfied most of the targeted design specifications.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.237-244
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• 2022

Onions are a significant crop in Korea, and cultivation is increasing every year along with high demand. Onions are planted in the fall and mainly harvested in June, the rainy season, therefore, physiological changes in onion bulbs during long-term storage might have happened. Onions are stored in cold room and at adequate relative humidity to avoid quality loss. In this study, bio-yield stress and weight loss were measured as the quality parameters of net packaged onions during 10 weeks of storage, and the storage environmental conditions are monitored using sensor networks systems. Quality estimation of net packaged onion during storage was performed using the storage environmental condition data through machine learning approaches. Among the suggested estimation models, support vector regression method showed the best accuracy for the quality estimation of net packaged onions.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.3
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• pp.117-124
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• 2023

In the machine vision inspection equipment, diameter measurement is important process in inspection of cylindrical object. However, machine vision inspection equipment requires complex algorithm processing such as camera distortion correction and perspective distortion correction, and the increase in processing time and cost required for precise diameter measurement. In this paper, we proposed the algorithm for diameter measurement of cylindrical object using the laser displacement sensor. In order to fit circle for given four input outer points, grid search algorithms using root-mean-square error and mean-absolute error are applied and compared. To solve the limitations of the grid search algorithm, we finally apply the singular-value-decomposition based circle fitting algorithm. In order to compare the performance of the algorithms, we generated the pseudo data of the outer points of the cylindrical object and applied each algorithm. As a result of the experiment, the grid search using root-mean-square error confirmed stable measurement results, but it was confirmed that real-time processing was difficult as the execution time was 10.8059 second. The execution time of mean-absolute error algorithm was greatly improved as 0.3639 second, but there was no weight according to the distance, so the result of algorithm is abnormal. On the other hand, the singular-value-decomposition method was not affected by the grid and could not only obtain precise detection results, but also confirmed a very good execution time of 0.6 millisecond.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.491-492
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• 2021

현대사회의 물류 현장에서 근로자가 직접 물류를 분류하는 작업을 하거나 상하차 작업을 진행하고 있다. 본 논문에서 제안하는 자율주행 로봇을 이용한 물류 분류 시스템은 물류 운반 로봇과 컨베이어 벨트로 구성된다. 물류 운반 로봇은 경로 설정 및 장애물 감지가 가능한 자율주행 기능을 가지며, 컨베이어 벨트는 하차된 물류의 무게 측정과 배송 가격을 표시하는 기능을 가진다. 본 연구의 결과는 근로자들의 노동 강도와 육체적 또는 정신적인 피해로 인해 발생하는 산업재해의 발생률을 감소시킬 수 있는 기대와 심야 시간에 부족한 인력을 보충하여 24시간 물류센터를 가동할 수 있는 가능성을 가진다.

• Journal of Korea Multimedia Society
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• v.15 no.3
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• pp.291-298
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• 2012

In automatic target recognition(ATR) systems, target extraction techniques are very important because ATR performance depends on segmentation result. So, this paper proposes a multi-sensor image fusion method based on adaptive weights. To incorporate the FLIR image and CCD image, we used information such as the bi-modality, distance and texture. A weight of the FLIR image is derived from the bi-modality and distance measure. For the weight of CCD image, the information that the target's texture is more uniform than the background region is used. The proposed algorithm is applied to many images and its performance is compared with the segmentation result using the single image. Experimental results show that the proposed method has the accurate extraction performance.