• Journal of Digital Contents Society
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• v.13 no.4
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• pp.491-500
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• 2012

In this paper, a new loopback BIST structure which is effective to test RF transceiver chip and LNA(Low Noise Amplifier) in the chip is presented. Because the presented BIST structure uses a baseband processor in the chip as a tester while the system is under testing mode, the developed test technique has an advantage of performing test application and test evaluation in effectiveness. The presented BIST structure can change high frequency test output signals to a low frequency signals which can make the CUT(circuits under test) tested easily. By using this technique, the necessity of RF test equipment can be mostly reduced. The test time and test cost of RF circuits can be cut down by using proposed BIST structure, and finally the total chip manufacturing costs can be reduced.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1117-1120
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• 2001

Chemical mechanical planarization(CMP) has emerged as the planarization technique of choice in both front-end and back-end integrated circuit manufacturing. Conventional CMP process utilize a polyurethane polishing pad and liquid chemical slurry containing abrasive particles. There have been serious problems in CMP in terms of repeatability and defects in patterned wafers. Since IBM's official announcement on Copper Dual Damascene(Cu2D) technology, the semiconductor world has been engaged in a Cu2D race. Today, even after~3years of extensive R&D work, the End-of-Line(EOL) yields are still too low to allow the transition of technology to manufacturing. One of the reasons behind this is the myriad of defects associated with Cu technology. Especially, dishing and erosion defects increase the resistance because they decrease the interconnection section area, and ultimately reduce the lifetime of the semiconductor. Methods to reduce dishing & erosion have recently been interface hardness of the pad, optimization of the pattern structure as dummy patterns. Dishing & erosion are initially generated an uneven pressure distribution in the materials. These defects are accelerated by free abrasive and chemical etching. Therefore, it is known that dishing & erosion can be reduced by minimizing the abrasive concentration. Minimizing the abrasive concentration by using Ce$O_2$ is the best solution for reducing dishing & erosion and for removal rate. This paper introduce dishing & erosion generating mechanism and a method for developing a semi-rigid abrasive pad to minimize dishing & erosion during CMP.

• Journal of Environmental Policy
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• v.7 no.1
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• pp.31-52
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• 2008

It has been attempted to minimize the environmental impacts due to railroad and road constructions. But assessments of the impact for the unwanted discharges by tunneling are still poorly systematic due to lack of scientific evaluation results ; thus, the tunneling projects frequently cause wide social conflicts. The goal of this study is to provide a guideline for appropriate environmental impact forecasts, assessments, and mitigation planning of tunneling projects.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.473-474
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• 2009

In this study, a column member of an existing architecture finished with gypsum board was assumed to examine fire resistance characteristics according to the type and thickness of finishing material. All specimens showed spalling to the reinforcing part after fire resistance test. For temperature characteristics, rapid temperature increase of 100${\sim}$200 $^{\circ}C$ was shown between 35 ${\sim}$ 60 minutes in the sequence of 9.5 T, 9.5 T (2 pieces), 12.5 T, 15 T and fire resistant 12.5 T. The analysis suggested that finishing materials with better fire resistance are necessary.

• The Journal of the Korean dental association
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• v.22 no.10 s.185
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• pp.865-868
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• 1984

Three Korean rapidly progressive periodontitis patient (R.P.P.) were examined for the isolation and identification of black-pigmented Bacteroides and Bacteroides gingivalis in the subgingival plaque. Black-pigmented Bacteroides and Bacteroides gingivalis were recovered from all three R.P. patients and the predominant isolates were Bacteroides intermedius followed by Bacteroides gingivalis. The B. gingivalis isolated from subgingival plaque of rapidly progressive periodontitis patients were Gram-negative pleomorphic rods and each produced brown to black colonies on blood agar plate supplemented with 5% rabbit 5ug/ml haemin, 0.5ug/ml of menadione and 40ug/ml of Kanamycin. The B. gingivalis isolated were fermented none of Glucose, Sucrose, Lactose, Esculin and Cellobinose and produced indole. Isolation and identification of Bacteroides gingivalis in Korean R.P. patients can be contributed to the research on the pathogenesis of Korean periodontal disease.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.4
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• pp.351-372
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• 2001

Im Rahmen der Kognitionswissenschaft werden im Grunde zwei Modelle zur menschlichen Informationsverarbeitung vertreten: Symbolismus und Konnektionismus. Aus diesen beiden Modellen lassen sich ebenfalls zwei $Ans\"{a}tze$ zur Sprachverarbeitung, insbesondere zur morphologischen Verarbeitung ableiten. So sind beim konnektionistischen Ansatz $regul\"{a}re\;sowie\;irregul\"{a}re$ Flexionsformen einheitlich im $Ged\"{a}chtnis$ gespeichert und verarbeitet. Diese Vorstellung weicht sich radikal von den Grundannahmen des symbolorientierten Ansatzes, bei dem eine strikte Unterscheidung zwischen regelgeleiteten und gespeicherten Flexions­formen untemommen wird. Hierbei werden $regul\"{a}re$ Flexionsformen durch symbolische Regeln, die ein Affix mit einem Stamm oder einer Wurzel verbinden, abgeleitet: $irregul\"{a}re$ Flexionsformen sind dagegen im $Ged\"{a}chtnis$ gespeichert. Der wesentliche Unterschied zwischen konnektionistischem und symbolischem Modell besteht demnach darin, dass nur beim letzteren die mentale Existenz linguistischer Regeln angenommen wird. Zahlreiche Untersuchungen zur $Repr\"{a}sentation$ und Verarbeitung der Flexionselemente im Deutschen als Muttersprache deuten darauf hin, dass das symbolische Modell plausibler ist als das konnektionistische. Vor diesem Hintergrund sind in der vorliegenden Untersuchung Ergebnisse aus einem psycholinguistischen Experiment zur morphologischen Verarbeitung im Deutschen als Zweitsprache vorgestellt und diskutiert worden. Festzustellen ist, dass unsere Ergebnisse rnit den Grundannahmen des symbolorienteriten Modells zu vereinbaren sind.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.484-488
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• 2000

This paper proposes a highy efficient inverter circuit for fluorescent lamp inverters using two state capacitors. A waveform of full-wave rectification used as a direct current power supply at fluorescent lamp inverters contains a lot of harmonic wave from inrush current which is generated near the maximum of input voltage with purse shape when voltage smoothing capacitor is charged. Therefore, In order to suppress inrush current which will result in harmonic wave, This paper proposed a method to control abrupt charging current by use of charging voltage at pre-state capacitor. As the result of it, power factor comes to be improved through the suppression of harmonic wave generation at supply current. Validity as to this experiment is confirmed through simulation.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.3
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• pp.211-218
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• 2005

Switched Reluctance Motor(SRM) offers the advantages of simple and robust motor construction, high speed and high efficiency over a wide operating range of torque and speed, excellent controllability. However SRM has the disadvantages of high current harmonics, and low power factor because the required output of speed and torque is produced by the discontinuous and loss of power system, and brings about the incorrect operation of electronic system. This paper deals with an energy efficient converter fed SRM system with the reduced harmonics and improved power factor. The validity of the proposed scheme is verified via experiments. We are implemented the proposed control system using 80C196KC micro-controller.

• Journal of the Korean Geographical Society
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• v.36 no.4
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• pp.343-355
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• 2001

Geomancy (feng-shui in Chinese and Pungsu in Korean) has had a significant impact on the Korean culture and is still practiced by many Koreans. This art is thought to have originated from the early Chinese people's search for an ideal site for preparing a cave dwelling. Ever since geomancy was introduced to Korea, it has been a crucial factor in the development of the Korean cultural landscape and the Korean geomentality. The current tendency of avoiding research into geomancy by the Korean geographers might have developed from their desire to avoid wrongly labeling themselves as geomancers and their discipline as geomancy studies. The geographer\`s aim of studying geomancy is not to prove the truthfulness of geomantic doctrines, but is to document and explain the impact of geomancy on the Korean culture.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12A
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• pp.1146-1152
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• 2005

In this paper, we propose a compressed quantized channel state information (CQCSI) feedback scheme for multi-carrier mobile communication systems. The proposed CQCSI figures out the contiguous subsequences of equal QCSI's as separate types of runs across the subcarriers, and then encodes the types of runs using a truncated Huffman coding algorithm. Computer simulation shows that the proposed algorithm can reduce the QCSI feedback up to one tenth of the uncompressed, while providing a comparable performance with the conventional QCSI feedback schemes. To cope with special cases when the frequency selective fading is very high, we also propose a restricted CQCSI feedback scheme. The restricted CQCSI feedback has been proved under vehicular B channel model.