• Journal of the Semiconductor & Display Technology
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• v.14 no.3
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• pp.23-26
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• 2015

A seam carving based micro-crack detection method is proposed which aims at detecting the micro-crack regions in heterogeneously textured surface of polycrystalline solar cells. By calculating the seam which is a connected path of low energy pixels in the image, the micro-crack regions can be detected. Experimental results show that the proposed seam carving based micro-crack detection method has superior efficiency in detecting the micro-crack without background noise pixels and the algorithm's computation time is less than the conventional algorithm.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.27-33
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• 2019

Quadrature spatial modulation (QSM) utilizes the in-phase and quadrature spatial dimensions to transmit the real and imaginary parts, respectively, of a single signal symbol. Improved QSM (IQSM) builds upon QSM to increase the spectral efficiency by transmitting the real and imaginary parts of two signal symbols using antenna combinations of size of two. In this paper, we propose a double QSM (DQSM) scheme that transmits the real and imaginary parts of two signal symbols independently through any of the transmit antennas. The two signal symbols are drawn from two different constellations of the same size with the first symbol drawn from any of the conventional modulation sets while the second is drawn from an optimally rotated version of the first constellation. The optimum rotation angle is obtained through extensive Monte Carlo simulations to minimize the bit error rate (BER) of the system. Simulation results show that for a given spectral efficiency, DQSM performsrelatively close to IQSM while requiring a smaller number of transmit antennas, and outperformsIQSM by up to 2 dB when the same number of antennas are used.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.34-40
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• 2019

In spatial modulation (SM), both the signal symbol and spatial symbol, i.e., the index of the antenna from which signal symbol is transmitted, carry information. To increase the number of bits carried by spatial symbols, more transmit antennas are required. In the generalized SM (GSM), the same signal symbol is transmitted from a combination of antennas, resulting in a reduction in the number of antennas required to achieve a given spectral efficiency. In this paper, we propose a rotated-symbol GSM (RGSM), in which the signal symbol is rotated with an angle corresponding to the position of the antenna index within the combination. This increases the number of spatial symbols by a factor equivalent to the length of the antenna combinations of the GSM. Numerically, SM, GSM and RGSM require 128, 17 and 12 transmit antennas to convey seven bits through the spatial symbols. Simulation results show that RGSM performs relatively close to GSM, and in several system settings, their error performances coincide.

• 대한공업교육학회지
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• v.31 no.2
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• pp.128-154
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• 2006

In the knowledge-based society, the quality of education is the core factor of national development. Above all, for improving educational quality, it is important to advance teacher's quality. Therefore, in order to maintaining high-level quality of education, it is required to select and appoint competent teacher. It deserves emphasis on importance of teacher recruitment test for maintaining high-level quality of education in this changes of age. Specially, Secondary School Teacher Recruitment Test of Electricity Electronics Communication Subject is declined qualitatively as each Subject of Electricity Electronics Communication is integrated and criterion of examination is obscured. This research analyzed The seventh curriculum and curriculum of Institution of Teacher Education of Electricity Electronics Communication Subject and already known examination of it On the basis of analyzing result, A field, proportion and points of examination decided through a expert conference are as follow: first, Teacher Recruitment Test of Electricity Electronics Communication Subject consists of subject pedagogics and contents. a proportion of subject pedagogics is 20% and subject contents is 80%. second, a subfield of subject contents consists of industrial education, industrial curriculum, industrial instruction method, practical guidance method, management of practical field organization, assesment of industrial education, industrial-educational cooperation and vocation and career education. third, subject contents consists of a common special, foundation special and application special field. a common a proportion of special field is 7.4%, foundation special is 20% and application special field which consists of electric field(21.3%), electronic field(21.3%) and communication field(10%) is 52.6%. fourth, Teacher Recruitment Test of Electricity Electronics Communication Subject execute practical technique test after finishing writing test.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.172-176
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• 2013

This paper presents a modified filtered-x least mean square (FxLMS) algorithm to improve the stability of active noise control (ANC) system in realistic environment. A real-time ANC system employing modified FxLMS is designed and implemented on digital signal processor (DSP) board. The ANC system is evaluated for cancelling various tonal frequency noises in the range from 100 to 500 Hz and the performance is measured in terms of sound pressure level (SPL) attenuation. Experiment results show that a quiet zone with maximum 20 dB SPL attenuation can be generated around the location of error microphone.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.82-86
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• 2012

These days, the cruise tourist industry is one of the most dynamic and fastest growing components of the leisure industry in the world. Therefore, the cruise ship with ubiquitous technology is expected to enhance the operation efficiency of the ship. It can also provide valuable addition to the ship's service as well as high quality of life to crews and passengers. Since a large number of passengers are dwelling in cruise ship, all passengers are not easy to use ship's facilities, such as restaurants, fitness center, swimming pool and spa at anytime they want. In this paper, passenger service system in ship environment is tested in similar environment and under ship operation condition. We have proposed three applications of ubiquitous technology using Zigbee communication and LabView program.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.3
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• pp.599-606
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• 2016

Many people feel uncomfortable when fitness center is crowded with people in all at the same time. So we propose exercise machines reservation system for resolving the problem that people feel uncomfortable in fitness center. In this paper, we design and implement the exercise machines reservation system that allows for users to reserve fitness equipments by using a NFC-based smart band. A user can reserve exercise machine using some reservation device. he or she will receive notifications through the smart band about when and which machine she or he will have to use. The user can do exercise with a recommended program, and can use any equipments conveniently even in a peak time because no one is waiting. Also, a manager can save cost through the efficient facility management and provide customized member management. Additionally, manager don't need to purchase other exercise machines or computers.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.1
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• pp.48-56
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• 2012

This paper deals with power electronic converter education program using LabVIEW. LabVIEW is a graphic based programming language with easy debugging, which is suitable for education program that can be used to study and figure out the operation of power electronic converters. When LabVIEW is employed as a simulation program of the operation of power electronic converters, the resulting program has the advantage such that the effects of the change of control variables and circuit parameters on the various variables such as the output voltage and the inductor current etc can be directly displayed without any separate compiling procedure. This paper shows the design procedure and the characteristics of the power electronics education program implemented by LabVIEW focusing on DC-DC converter among power electronic converters.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.12
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• pp.1011-1020
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• 2016

This paper introduces a tactilely transparent soft glove composed of soft materials and flexible structures. Although it is hard to achieve a high grasping force with conventional grip-assist gloves made from soft material, the proposed glove can exert a high force by using a novel structure. This structure has a triangular shape composed of flexible structural frames, soft fabric, and belts. It can produce grip-assist moment compliantly without harmful force or misalignment with the human fingers. The whole finger part that comes into contact with objects is made of thin and soft fabric in order to facilitate sensation transference. The proposed tactilely transparent soft glove enables the user to manipulate various objects owing to both the softness and high grasping force; it helps lifting heavy weight objects as well as permitting delicate tactile feeling on the palm and fingers. The proposed concept was applied to a two-finger grip-assist device for validation. In addition, the experimental results regarding grasping objects, fingertip force, and grasping force are presented.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.1
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• pp.140-146
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• 2018

Recently, VLC(Visible Light Communication) fusing with LED(Light Emitting Diode) used in indoor lighting and wireless communication technology has attracted attention. However, the VLC can communicate only within the coverage to measure the optical signal and the communication disconnection phenomenon is occur in the NLoS(Non-Line-of-Sight) area. In this paper, we propose VLC relay module to extend the coverage of VLC and improve the communication disconnection phenomenon in NLoS area. The proposed VLC relay module transmits the packet received from the transmitter to the VLC relay module and receiver. The experiment was carried out by installing one VLC transmitter and three VLC relay modules, communication coverage expansion and the improvement of communication disconnection phenomenon in the NLoS were confirmed by the increase of the VLC relay module. Also, we confirmed that the optical signal measurement performance is improved 2.4 times by using the dual sampling method.