• Journal of The Korean Astronomical Society
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• v.47 no.2
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• pp.43-47
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• 2014

Many advanced ground-based solar telescopes improve the spatial resolution of observation images using an adaptive optics (AO) system. As any AO correction remains only partial, it is necessary to use post-processing image reconstruction techniques such as speckle masking or shift-and-add (SAA) to reconstruct a high-spatial-resolution image from atmospherically degraded solar images. In the New Vacuum Solar Telescope (NVST), the spatial resolution in solar images is improved by frame selection and SAA. In order to overcome the burden of massive speckle data processing, we investigate the possibility of using the speckle reconstruction program in a real-time application at the telescope site. The code has been written in the C programming language and optimized for parallel processing in a multi-processor environment. We analyze the scalability of the code to identify possible bottlenecks, and we conclude that the presented code is capable of being run in real-time reconstruction applications at NVST and future large aperture solar telescopes if care is taken that the multi-processor environment has low latencies between the computation nodes.

• Structural Engineering and Mechanics
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• v.56 no.5
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• pp.813-833
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• 2015

Spherical reticulated shells are widely applied in structural engineering due to their good bearing capability and attractive appearance. Parametric modeling of spherical reticulated shells is the basis of internal analysis and optimization design. In the present study, generation methods of nodes and the corresponding connection methods of rod elements are proposed. Modeling programs are compiled by adopting the ANSYS Parametric Design Language (APDL). A shape optimization method based on the two-stage algorithm is presented, and the corresponding optimization program is compiled in FORTRAN environment. Shape optimization is carried out based on the objective function of the minimum total steel consumption and the restriction condition of strength, stiffness, slenderness ratio, stability. The shape optimization of four typical Schwedler spherical reticulated shells is calculated with the span of 30 m~80 m and rise to span ratio of 1/7~1/2. Compared with the shape optimization results, the variation rules of total steel consumption along with the span and rise to span ratio are discussed. The results show that: (1) The left and right rod-Schwedler spherical reticulated shell is the most optimized and should be preferentially adopted in structural engineering. (2) The left diagonal rod-Schwedler spherical reticulated shell is second only to left and right rod regarding the mechanical behavior and optimized results. It can be applied to medium and small-span structures. (3) Double slash rod-Schwedler spherical reticulated shell is advantageous in mechanical behavior but with the largest total weight. Thus, this type can be used in large-span structures as far as possible. (4) The mechanical performance of no latitudinal rod-Schwedler spherical reticulated shell is the worst and with the second largest weight. Thus, this spherical reticulated shell should not be adopted generally in engineering.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.270-287
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• 2015

According to the increase of the operating cost and material cost of a ship due to the change of international oil price, a demand for the lightening of the ship weight is being made from various parties such as shipping companies, ship owners, and shipyards. To satisfy such demand, many studies for a light ship are being made. As one of them, an optimal design method of an existing hull structure, that is, a method for lightening the ship weight based on the optimization technique was proposed in this study. For this, we selected a hatch cover of a bulk carrier as an optimization target and formulated an optimization problem in order to determine optimal principal dimensions of the hatch cover for lightening the bulk carrier. Some dimensions representing the shape of the hatch cover were selected as design variables and some design considerations related to the maximum stress, maximum deflection, and geometry of the hatch cover were selected as constraints. In addition, the minimization of the weight of the hatch cover was selected as an objective function. To solve this optimization problem, we developed an optimization program based on the Sequential Quadratic Programming (SQP) using C++ programming language. To evaluate the applicability of the developed program, it was applied to a problem for finding optimal principal dimensions of the hatch cover of a deadweight 180,000 ton bulk carrier. The result shows that the developed program can decrease the hatch cover's weight by about 8.5%. Thus, this study will be able to contribute to make energy saving and environment-friendly ship in shipyard.

• Journal of the Semiconductor & Display Technology
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• v.10 no.3
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• pp.1-6
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• 2011

In this paper, the IC(Integrated Circuit) for multi-channel synchronous communication was designed by using FPGA and VHDL language. The existing chips for synchronous communication that has been used commercially are composed for one to two channels. Therefore, when communication system with three channels or more is made, the cost becomes high and it becomes complicated for communication system to be realized and also has very little buffer, load that is placed into Microprocessor increases heavily in case of high speed communication or transmission of high-capacity data. The designed IC was improved the function and performance of communication system and reduced costs by designing 8 synchronous communication channels with only one IC, and it has the size of transmitter/receiver buffer with 1024 bytes respectively and consequently high speed communication became possible. It was designed with a communication signal of a form various encoding. To detect errors of communications, the CRC-ITU-T logic and channel MUX logic was designed with hardware logics so that the malfunction can be prevented and errors can be detected more easily and input/output port regarding each communication channel can be used flexibly and consequently the reliability of system was improved. In order to show the performance of designed IC, the test was conducted successfully in Quartus simulation and experiment and the excellence was compared with the 85C3016VSC of ZILOG company that are used widely as chips for synchronous communication.

• English Language & Literature Teaching
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• v.15 no.2
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• pp.225-243
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• 2009

This study investigates the use of different speech act of apology strategies between male and female EFL college students by comparing the components of intensity, stylistic competence, and semantic formulas. The data was collected from 37 participants who were studying freshmen English reading course at the Department of English Education of C University in Seoul. Most students were English majors taking pre-teacher course of teaching English for secondary school students. The participants were divided into two gender groups of male and female. The discourse completion test (DCT) which was revised from the speech act of apology by Olshtain and Cohen (1990) was provided with the participants after the researcher explained the speech act of apology in ten situations. The speech act of apology depends on situation variables: social solidarity, severity of offense, and social status. The results show that in the preference of intensity, male and female have almost the similar ratio in high (female: 24.7%, male 24%) and low intensity (female: 75.3%, male: 76%). In the use of stylistic competence, male group (21%) expresses more diversely formal features than female group (12%), while female (87%) use more informal features than male (66%). Most of participants show a limitation in the use of speaking four types of semantic formulas: expression of apology (APOL), acknowledgment of responsibility (RESP), offer of repair (REPR), and promise of forbearance (FORB). As nonnative speakers, the participants cannot conduct the semantic formula in some situations regardless of the tasks provided. The results suggest that English teachers should recognize pragmatic variations in which students feel difficulty in appropriate speaking strategies on apology. This study also contributes to teaching learners the strategies and speaking patterns in the course of various apology situations.

• The Journal of Information Systems
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• v.15 no.1
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• pp.1-20
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• 2006

Peer-to-peer systems (P2P) are rapidly growing in importance on the Internet environment, quickly extending the range of their usage. However, peer-to-peer systems have not been widely applied in electronic commerce because they have not been established as an appropriate business model. Therefore, we firstly review the previous research relevant to peer-to-peer systems, and then analyze the business models for P2P systems presented by previous researchers. Furthermore, this study categorizes major issues in terms of the technical and business model aspects. On the basis of these reviews, we develop P2P electronic commerce systems based on the file sharing method between users, focusing on user interface friendliness. A developed P2P electronic commerce systems are programmed by using the C# based on the Microsoft.net solution. A database is implemented using the MSSQL2000. A main application technology is designed that P2P electronic commerce systems make it possible. for user to extend into BtoB Solution by using WSDL (Web Services Description Language), UDDI (Universal Description, Discovery, and Integration) and the XML that is a document for users. User interface is made as form of Internet messenger for a user's convenience and is possible to develop into a commodity transaction system based on XML. In this study, it is possible for the P2P electronic commerce system to have extended application to fields such as Internet shopping mall and property transaction in a nonprofit organization, a public institution and a large scale nonprofit institution that have a similar structure as compared with a structure of a nonprofit educational institution.

• Journal of architectural history
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• v.16 no.1
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• pp.29-48
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• 2007

This study is an investigation that explication of the reading method of transcription marking, and explains what it means and where to use transcription marking of architectural vocabulary. focusing on timber class vocabulary from on SeoGwolYeongGeonDoGamUiGwe(${\ulcorner}$西闕營建都監儀軌(1831)${\lrcorner}$). This study is reviewed sequentially classifying items according to timber class, stone class, iron class architectural vocabulary. This treatise, named 'Architectural Vocabulary Study (1)', is mainly focused on making out a transcription marking of timber class vocabulary on the documents. But, because of the properties of the UiGwe(儀軌), there are some different expressions used for the same vocabulary. Therefore, the different expressions are referenced according to vocabulary used from the 17th century to the 20c century. This study lists timber class architectural vocabulary of transcription marking on SeoGwolYeongGeonDoGamUiGwe(${\ulcorner}$西闕營建都監儀軌(1831)$\lrcorner$). This study also explicates and explains the meaning of them. In advance, this study compares them with the vocabulary of national language in the middle ages and modern times. If we could explicate the transcription marking of the documents as it is, we can't only recover plenty of vocabulary related with characteristic architecture in the age of later Chosun Dynasty, but also correct wrongly used vocabulary nowadays. With the results, we can standardize and adjust vocabulary use of Korean traditional architecture. In advance, we can correct errors of spelling and mistaken explanation in the Korean Encyclopedia.

• Journal of Magnetics
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• v.21 no.2
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• pp.266-272
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• 2016

Transcranial magnetic stimulation devices has been used mainly for diagnostic purposes by measuring the functions of the nervous system rather than for treatment purposes, and has a problem of considerable energy fluctuations per repeated pulse. The majority of strokes are caused by ischemia and result in brain tissue damage, leading to problems of the central nervous system including hemiparesis, dysfunction of language and consciousness, and dysfunction of perception. Control is difficult and the size is large due to the difficulty of digitalizing the energy stored in a capacitor, and there are many heavy devices. In addition, there are many constraints when it is used for a range of purposes such as head and neck diagnosis, treatment and rehabilitation of nerve palsy, muscle strengthening, treatment of urinary incontinence etc. Output stabilization and minimization of the energy variation rate are required as the level of the transcranial magnetic stimulation device is dramatically improved and the demand for therapeutic purposes increases. This study developed a compact, low cost transcranial magnetic stimulation device with minimal energy variation of a high repeated pulse and output stabilization using a real time capacitor charge discharge voltage. Ischemia was induced in male SD rats by closing off the common carotid artery for 5 minutes, after which the blood was re-perfused. In the cerebrum, the number of PARP reactive cells after 24 hours significantly decreased (p < 0.05) in the TMS group compared to the GI group. As a result, TMS showed the greatest effect on necrosis-related PARP immuno-reactive cells 24 hours after ischemia, indicating necrosis inhibition, blocking of neural cell death, and protection of neural cells.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1C
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• pp.78-85
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• 2007

With the advancement of the digital broadcasting and popularity of the Internet, recently, many studies are making on the digital watermarking for the copyright protection of digital data. This paper proposes the minimum modification method of motion vector to minimize the degradation of video quality, hiding subtitles of many language and information of OST(original sound track), character profiles, etc. as well as the copyright protection. Our proposed algorithm extracts feature vector by comparing motion vector data with watermark data, and minimize the modification of motion vectors by deciding the inversion of bit. Thus the degradation of video quality is minimized comparing to conventional algorithms. This algorithm also can check data integrity, and retrieve embedded hidden data simply and blindly. And our proposed scheme can be useful for conventional MPEG-1, -2 standards without any increment of bit rate in the compressed video domain. The experimental result shows that the proposed scheme obtains better video quality than other previous algorithms by about $0.5{\sim}1.5dB$.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2563-2573
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• 1999

In most mail automatic processing centers, after facing and canceling, letter mails are passed through an Optical Character Recognition/Barcode Sorter(OCR/BS) to read the postal code and 3 of 5 fluorescent (luminescent) barcode is applied. Normally, 31%∼35% of this mails are rejected. The main reasons for reading failures are poor printing quality of addresses and barcodes, script printing, writing in a cursive hand, variety fonts, and failure to locate the address. Our goal is to provide mailer with top quality service and customer barcode service as we move toward 100% barcoding automation of letter mail. In this paper, we propose a method of printing 3 of 5 customer barcode, postal code management, and detection of postal code based on postal address for increase the performance of automatic processing system in mail items. Using postal code generating rules, which are automatically extracted from postal addresses and address numbers, creates postal codes. The customer barcode support system is implemented by C++ language and runs on IBM PC under Windows 95.