• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.5
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• pp.147-153
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• 2018

Beacon enables one to measure distance indoors based on low-power Bluetooth low energy (BLE) technology, while GPS (Global Positioning System) only can be used outdoors. In measuring indoor distance using Beacon, RSSI (Received Signal Strength Indication) is considered as the one of the key factors, however, it is influenced by various environmental factors so that it causes the huge gap between the estimated distance and the real. In order to handle this issue, we propose the adaptive ANN (Artificial Neural Network) based approach to measuring the exact distance using Beacon. First, we has carried out the preprocessing of the RSSI signals by applying the extended Kalman filter and the signal stabilization filter into decreasing the noise. Then, we suggest the multi-layered ANNs, each of which layer is learned by specific training data sets. The results showed an average error of 0.67m, a precision of 0.78.

• Journal of the Korean Home Economics Association
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• v.20 no.3
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• pp.9-18
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• 1982

In this study, we attempted to make an original pattern of clothing for an abnormal type of figure, especially for the type of kyphosis. We measured the curvature of the spine of a woman with kyphosis with a Martin measuring instrument and a silhouetter in the following ways. First, we counted the rate of shrinkage of the standard lines drawn on the surface of the body according as the body moved. Secondly, placing the front and back darts, the front and back shoulder darts and the side darts according to“Munhwa”pattern, we made cubic cuttings of four moving postures as well as the standing one. Thirdly, we superposed the developed patterns of the standing and the moving postures, measuring the position change and the amount of the chaange of the darts, and compared them. The results are as follows: 1) In the developed pattern of a cubic cutting of the basic pattern and the standing posture, the neckhole became larger than that of the basic pattern, and the waist line was lowered than that of the basic pattern because the center back line was shortened due to the curved backbone. 2) As for the change of the standard line according to the movement, we found that the waist line, the center front line, the center back line, the bust width line, the upper back width line and the back width line became longer. Special consideration must be given to the function of the clothing for an abnormal type of figure. 3) The difference of the measurements between the cubic cutting and the body measurement regardless of the body movement is due to a gap by an acute angle at the jutted place between the developed pattern and the body surface. We found that the body measurement of the upper back width line, the back width line and the bust line became larger. Consequently, in making an original clothing pattern, it is desirable that we must not place the front and the back waist darts at the jutted place on the back from the functional and the aesthetic viewpoint of clothing. It is also desirable that we must widen the neckhole because the shoulder angle is close to a straight line due to a jut of the upper back width line.

• Journal of Sensor Science and Technology
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• v.1 no.2
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• pp.147-154
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• 1992

This paper describes the design of implantable 8-channel telemetering system to get physiological signals. The internal circuits of this system are designed not only to achieve as small size and low power dissipation as possible, but also to enable continuous measurement of physiological signals. Its main functions are to enable continuous measurement of physiological signals and to accomplish on-off power switching of an implantable battery by receiving appropriate command signals from an external circuit. To integrate implantable biotelemetry system, we performed layout of internal system using Lambda based $2{\mu}m$ n-well design rules. This system, used together with appropriate sensors, is expected to be capable of measuring and transmitting such significant parameters as pressure, pH, and temperature.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.52.2-52.2
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• 2011

본 연구의 목적은 CIGS 태양전지의 두 가지 TCO층 중 AZO를 제외한 intrinsic ZnO의 전자빔 처리 영향에 대한 특성 분석을 하고자 함이다. 또한 추후 CIGS 태양전지를 제조하여 적용 시 전자빔 처리 전후의 특성이 어떻게 변하는지를 알아보기 위한 사전 실험이다. Intrinsic ZnO는 RF magnetron sputter 를 이용하여 약 100nm의 두께로 증착 하였다. 이때 공정 압력을 변수로 RF power는 80W로 설정 하였으며 Ar 분압은 10mtorr, 5mtorr, 1mtorr로 각각 달리 하며 증착 하였다. 이후 전자빔 처리를 위해 각각의 시편에 Argon flow 7sccm 상태에서 DC power 3kW, RF power 300W의 세기로 전자빔 처리를 실시 하였다. 전자빔 처리에 따른 전기적, 구조적 특성을 분석하기위해 Hall measurement와 SEM, XRD, UV-vis spectroscopy을 사용하였다. 먼저 Hall measurement 측정을 통한 전기적 분석 결과 비저항이 무한대에서 약 $40m{\Omega}{\cdot}cm$로 감소된 결과를 도출 할 수 있었으며, $2{\sim}3.4{\times}10^{18}/cm^3$ 이상의 carrier density 가 측정 되었다. UV-vis spectroscopy를 이용한 투과도 측정결과 모든 시편에서 Band gap이 감소하는 결과를 보였다. SEM, XRD를 이용한 분석결과 결정성 및 grain의 크기가 증가하는 결과를 얻을 수 있었다.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.2
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• pp.291-298
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• 2020

Sign language was designed for the deaf and dumb people to allow them to communicate with others and connect to the society. However, sign language is uncommon to the rest of the society. The unresolved communication barrier had eventually isolated deaf and dumb people from the society. Hence, this study focused on design and implementation of a wearable sign language interpreter. 6 inertial measurement unit (IMU) were placed on back of hand palm and each fingertips to capture hand and finger movements and orientations. Total of 28 proposed word-based American Sign Language were collected during the experiment, while 156 features were extracted from the collected data for classification. With the used of the long short-term memory (LSTM) algorithm, this system achieved up to 99.89% of accuracy. The high accuracy system performance indicated that this proposed system has a great potential to serve the deaf and dumb communities and resolve the communication gap.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.91-109
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• 1991

The purpose of this study were to comfirm the effects of the thickness and kinds of porcelain, etchants, illumination time, elapsed time for the measurement, and chemical cure component to the bond strength of porcelain laminate and composite resin cement, and to compare the effects between the light cured resin and the dual cured resins. The etched porcelain surface, the sectioned surface crossing porcelain and resin after bonding, and the debonded surfaces were observed by the SEM. One product of laminate porcelain powder, one light cured resin and two dual cured resins were selected. Each resin cements are lightened through the thin porcelain disc which was cut from cylindrical porcelain specimen by the diamond saw, and by the light through the porcelain disc they were bonded. Changes of thickness and kinds of porcelain, etchants, illumination time, and the elapsed time for the measurement were considered as variables for the bond strength. And the bond strength of porcelain and dual cured resins under the conditions of autopolymerization or the removal of chemical cure component were measured and compared. Bond strength were measured by shear stress. The etched surface, the cross-sectioned surface, and the debonded surface of porcelain or resin were observed by SEM. On the summary of this study, the following conclusions can be stated; 1. Bond strength of light cured resin was decreased inversely by the thickened porcelain laminate and showed the lowest value to the masking dentin porcelain among 4 kinds of porcelain powder. 2. Bond strength of autopolymerization of dual cured resin without illumination in dark chamber were from 75% to 98% to the data of dual cured resin with illumination. 3. Bond strength of dual cured resin used without chemical cured components were same to them of light cured resin. 4. Cross-sectioned surface treated by silane did not show the gap between the porcelain and resin. 5. Illumination over 80 seconds did not make the significant increase of bond strength on all kinds of resin.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.8
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• pp.527-534
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• 2013

The software is changed according to the changing businesses and the user requirement, it involves increasing complexity and cost. Considering the repetitive changes required for the software, replacement is more efficient than maintenance at some point. In this study, the replacement time was predicted using the service dissatisfaction index and replacement point assessment index by the software group for each task. First, fuzzy inference was used to develop the method and indicator for the user's service level dissatisfaction. Second, the replacement point assessment method was established considering the quality, costs, and new technology of the software. Third, a replacement time prediction technique that used the gap between the user service measurement and replacement point assessment values was proposed. The results of the case study with the business solutions of three organizations, which was conducted to verify the validity of the proposed prediction technique in this study, showed that the service dissatisfaction index decreased by approximately 16% and the replacement point assessment index increased by approximately 9%.

• Journal of radiological science and technology
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• v.43 no.6
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• pp.481-487
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• 2020

Radiation measurement technology has steadily improved and its usage is expanding in various industries such as nuclear medicine, security search, satellite, nondestructive testing, environmental industries and the domain of nuclear power plants (NPPs). Especially, the simultaneous measurements of gamma rays and neutrons can be even more critical for nuclear safety management of spent nuclear fuel and monitoring of the nuclear material. A semiconductor detector comprising cadmium, zinc, and tellurium (CZT) enables to detect gamma-rays due to the significant atomic weight of the elements via immediate neutron and gamma-ray detection. Semiconductor sensors might be used for nuclear safety management by monitoring nuclear materials and spent nuclear fuel with high spatial resolution as well as providing real-time measurements. We aim to introduce a portable nuclide-analysis device that enables the simultaneous measurements of neutrons and gamma rays using a CZT sensor. The detector has a high density and wide energy band gap, and thus exhibits highly sensitive physical characteristics and characteristics are required for performing neutron and gamma-ray detection. Portable nuclide-analysis device is used on NPP-decommissioning sites or the purpose of nuclear nonproliferation, it will rapidly detect the nuclear material and provide radioactive-material information. Eventually, portable nuclide-analysis device can reduce measurement time and economic costs by providing a basis for rational decision making.

• Journal of Drive and Control
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• v.20 no.3
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• pp.15-24
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• 2023

The aim of this study was to measure and evaluate the exhaust emission factors of agricultural tractors. Engine characteristics and three exhaust emissions (CO, NO_x, PM) were collected under actual agricultural operating conditions. Experiments were performed on idling, driving, plow tillage, and rotary tillage. The load factor (LF) was calculated using the collected engine data, and the emission factor was analyzed using the LF and exhaust emissions. The engine characteristics and exhaust emissions were significantly different for each working condition, and in particular, the LF was significantly different from the currently applied 0.48 LF. The data distribution of exhaust emissions was different depending on the engine speed. In some conditions, the emission factor was higher than the exhaust emission standards. However, since most emission limit standards are values calculated using an engine dynamometer, even if the emission factor measured under actual working conditions is higher, it cannot be regarded as wrong. It is expected that the results of this study can be used for the inventory construction of a calculation for domestic agricultural machinery emissions in the future.

• Journal of Yeungnam Medical Science
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• v.41 no.2
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• pp.80-85
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• 2024

Background: This study aimed to compare and evaluate the marginal fit of nanocomposite computer-aided design/computer-aided manufacturing (CAD/CAM) inlays. Three types of nanocomposite CAD/CAM blocks (HASEM, VITA Enamic, and Lava Ultimate) were used as materials. Methods: Class II disto-occlusal inlay restorations were prepared on a typodont mandibular right first molar using diamond rotary instruments. The inlays were fabricated using CAD/CAM technology and evaluated using the silicone replica technique to measure marginal gaps at five locations on each inlay. The data were analyzed by two-way analysis of variance and Tukey post hoc tests (α=0.05). Results: There were no significant differences in the marginal gaps based on the type of nanocomposite CAD/CAM inlay used (p=0.209). However, there was a significant difference in the marginal gaps between the measurement regions. The gingival region consistently exhibited a larger marginal gap than the axial and occlusal regions (p<0.001). Conclusion: Within the limitations of this in vitro study, the measurement location significantly influenced the marginal fit of class II disto-occlusal inlay restorations. However, there were no significant differences in the marginal gaps among the different types of CAD/CAM blocks. Furthermore, the overall mean marginal fits of the class II disto-occlusal inlay restorations made with the three types of nanocomposite CAD/CAM blocks were within the clinically acceptable range.