• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.709-711
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• 2005

Developing fault location system for underground power cable which can detect its fault location exactly require very high speed data acquisition and signal processing capability. We are developing fault location system which is different from conventional fault locator. This fault location system monitor underground power cable by using on-line speed current sensor and if there are an accident, it record its transient signal and calculate fault location by analyzing it. Signals which acquired when power cable fault arise, showed transient characteristics and its frequency band is very hish. So, to develop fault location system, we designed special high speed data acquisition and signal processing board. In this thesis, we describe on data acquisition and signal processing H/W design for fault location system on underground power cable.

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.65-68
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• 2003

3kW grid-connected photovoltaic(PV) systems and data acquisition system are constructed for performance analysis of PV system at field demonstration test center of Gwang-Ju in Korea. As climatic and irradiation conditions are varied, operation characteristics of the PV system are collected and analyzed in data acquisition system. From these results, the performances of PV systems have simulated and evaluated using simulation tool In comparison with actual value of data acquisition system of field demonstration test center. Furthermore, performance of each PV system e.g. electric power and loss factor is reviewed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8A
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• pp.898-908
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• 2004

In this paper, we propose a high speed preamble searcher feasible for RACH(Random Access Channel) preamble structure in WCDMA reverse link receiver. Unlike IS-95, WCDMA system uses AISMA(Acquisition Indication Sense Multiple Access) process. Because of the time limit between RACH preamble transmission and AI(Acquisition Indicators), and the restriction on the number of RACH signatures assigned to RACH preamble, fast acquisition indication is required for efficient operation. The preamble searcher proposed in this paper is based on 2-antenna system and has adopted FHT algorithm that has the radix-2 16 point FFT structure. The acquisition speed using FHT is 64 times faster than the conventional method that correlates each signature. Based on their fast aquisition scheme, we improved the acquisition performance by calculating the correlation up to the 4096 chips of the total preamble length. The performance is analyzed by using Neyman-pearson method. The proposed algorithm has been applied for the implementation of WCDMA reverse link receiver modem successfully.

• Journal of Labour Economics
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• v.27 no.1
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• pp.1-25
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• 2004

In knowledge-based economy where the human capital has an strong compatibilities, the life cycle of technologies and skills get shorter, and the mobility of labor get greater, the role of the signal system of qualifications have greater importance. This article used the KLIPS(Korean Labor Institute Panel Study) data, and analysed the factors of the acquisition of qualifications and the employment and wage effects of the acquisition of qualifications by fixed effects logit model and random effects model. The lower school stratification acquired the more qualifications, and in the case of men the unemployed one acquired the more qualifications. The employment effects of the acquisition of qualifications are significant at first year and second year in women, but the men's of the employment effects of acquisition of qualifications are not significant. The wage effects of the acquisition of qualifications are not significant. The results of the regression suggest that in Korea the signal system of qualifications do not working, and that the qualifications in Korea need to reform.

• Journal of the military operations research society of Korea
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• v.3 no.2
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• pp.49-77
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• 1977

Weapon systems are curcial instruments for the security of a nation and critical elements for the victory in a war. Since modern weapon systems tend to be capital-intensive with high precision and quality, they become more and more complex and diversified; their acquisition costs become huge; and their technological obsolescence becomes accelerated. Therefore, the systematic management of weapon acquisition process would be one of the most important defense tasks at the national level. To analyze such problems and find solutions, this paper has studied various aspects related to the efficient management of weapon system acquisition. After brief summarization of the general characteristics of weapon systems, their effectiveness, and developmental trend, the paper discusses the defense management policies and techniques for the weapon systems. Specifically, four alternative acquisition methods such as indigenous R & D, foreign purchase, co-production and joint-production are discussed and analyzed by systems approach. The systems analysis procedure to evaluate and select weapon acquisition method is as follows; 1) to analyze the merits and demerits of the alternative methods, 2) to screen unrealistic alternatives through the consideration of significant factors such as political, economic, military, technological, and social constraints, 3) to evaluate and select an optimal one among the remaining acquisition methods after the cost-effectivenss analysis. For the base of cost-effectivess analysis, cost analysis model as well as effectiveness analysis model of each acquisition method are developed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.11
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• pp.5481-5495
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• 2018

Single pixel imaging technology has developed for years, however the video acquisition on the single pixel camera is not a well-studied problem in computer vision. This work proposes a new scheme for single pixel camera to acquire video data and a new regularization for robust signal recovery algorithm. The method establishes a single pixel video compressive sensing scheme to reconstruct the video clips in spatial domain by recovering the difference of the consecutive frames. Different from traditional data acquisition method works in transform domain, the proposed scheme reconstructs the video frames directly in spatial domain. At the same time, a new regularization called spatial cluster is introduced to improve the performance of signal reconstruction. The regularization derives from the observation that the nonzero coefficients often tend to be clustered in the difference of the consecutive video frames. We implement an experiment platform to illustrate the effectiveness of the proposed algorithm. Numerous experiments show the well performance of video acquisition and frame reconstruction on single pixel camera.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.1
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• pp.39-45
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• 2011

The processes for manufacturing a product differ depending on the characteristics of the product, and the information used or generated by the processes also varies. To implement a flexible and configurable Manufacturing Execution System (MES), a Data Acquisition System (DAS) that takes into consideration the characteristics of the manufacturing system is required. In this study, we design an information acquisition system that can process the information on equipments of a shop floor in real-time and that is adaptive to the changes in the shop floor. The system has a data parser module for flexible processing of the equipment status, a data mapper module to link the equipment status with a manufacturing process, and an SOA-based data integration module to transmit the processed information to other information systems such as MES and ERP. From the results of pilot study, its maintenance is easy even if new equipment or new manufacturing processes are adopted or if the equipments are rearranged.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.11
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• pp.1211-1216
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• 2013

In this study, a dynamic camera actuation system for simultaneous in situ image acquisition is developed to achieve real-time observation of transient liquid flow on a lab-on-a-disk. A disk-type electric circuit, namely circuit-on-a-disk, co-rotated with the lab-on-a-disk improves the dynamic image acquisition ability in terms of a frame rate. The circuit-on-a-disk is comprised of a camera connected with a motor, a microprocessor and a wireless communication module. The camera connected with the motor enables to realize dynamic tracking of a transient flow and real-time image acquisition. The obtained images can be simultaneously transferred by a video/audio transmitter unit to a personal computer. Also, the microprocessor receives signals from the personal computer, and then controls the focusing position of the camera. We are expecting that heaters, sensors, and light sources also can be integrated on the circuit-on-a-disk, and they will enable various functional actuations as well as precise image acquisition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1510-1521
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• 1996

This paper presents acquisition algorithm and an improved detection technique for the DS/CDMA (direction sequence code division multiple access) RAKE receiver in multipath fading channel. The DS/CDMA systems use the RAKE receiver, an accurate code acquisition is required for the RAKE branches. The algorithmis able to findthe pseudonoise (PN) code delay estimates for the RAKE branches in a multipath fading channel. In this paper a numerical method and computer simulation simulation have been developed for the acquisition system. The detection probability and mean acquisition time are investigated asa performance measure of the system using the Monte Carlo method. And also in order to analyze the effect of the acquisition on the RAKE receiver this paper bring out the effect of integration time, doppler frequency, processing gain and the number of users on the acquired code phase.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1E
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• pp.22-26
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• 2000

In this paper, the DS/CDMA PN code acquisition system with nonlinear transmitter power amplifier based on digital matched filter (DMF) which has the rapid acquisition time is presented and the performance is evaluated in terms of mean acquisition time, detection probability, and signal to interference under multiuser environment. The performance is presented with respect to the output backoff of the nonlinear amplifier and the correlation window.