• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.45-56
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• 1999

A biofilter was established to remove the ammonia, which is representative nitrogen-contained malodorous gas. in a compost factory. Removal efficiency of ammonia and hydrogen sulfide also was investigated. A quantity of malodor gas produced in a compost factory was affected greatly by the weather. compost states and working condition of a fertilizing mixer, and the produced gas concentrations doubled by above various parameters. By operating a water scrubbing system for removing water-soluble malodorous gases effectively. we could improve the removal efficiency over three times. We investigated long-term stability of biofilter under continuous gas flow(SV=500h-1) for 100 days. The results showed 30 days of microbial retention time. After the days, deodorization efficiency of biofilter was kept steady state. and the removal efficiency was kept over 95% for ammonia and 97% for hydrogen so]fide. respectively. The electric consumption of the biofilter, which could treat malodorous gas of 100$\textrm{m}^3$/min, applied in the compost factory was evaluated about 80u0day and water consumption was 80~100$\ell$/day. These results concluded that the biofilter is a excellent deodorization technology as well as cost-effective for removing malodorous gas produced in a compost factory.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1415-1419
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• 2006

메탄을 탄소원 및 에너지원으로 이용하는 메탄산화균은 물질대사과정 중에 다량의 세포외 고분자물질인 Extracellular polymeric substances(EPS)를 생성하는데, EPS는 카르복실기와 같은 표면흡착 기능을 가지고 있어 생체흡착제로 사용이 가능하다. 따라서 본 연구에서는 메탄산화세균을 이용하여 중금속인 Cd의 흡착성능을 파악하여 활성슬러지의 흡착능과 비교하고, EPS 농도별, pH별 흡착량의 변화를 실험한 후 Freundlich 흡착모델식에 적용하여 흡착공정의 기본적인 설계인자를 도출하고자 하였다. 실험에 사용한 메탄산화세균은 매립지 복토층 상부 토양에서 분리하여 실험실에서 대량으로 배양하였으며, EPS 생성을 위해 메탄을 Head space의 20%를 주입하고 $30^{\circ}C$, 150rpm에서 질소원이 부족한 조건으로 48hr 동안 배양하였다. Cd의 흡착실험은 용액의 pH를 3에서 8까지 변화를 주면서 활성슬러지와 메탄산화세균의 시간별 흡착능을 측정하였다. 또한 중금속의 농도별 흡착능을 측정하여 흡착평형 상수를 파악하였으며, 중금속 흡착 전, 후 미생물의 SEM 촬영, FT-IR 분석, 전자현미분석(EPMA)을 통하여 무기성분 분석 및 표면관찰을 수행하였다. 실험결과 메탄산화세균에 의해 생성된 EPS 물질은 중금속에 대한 강한 결합능력이 있으며, Cd에 대한 최고 흡착능은 26mg Cd(Ⅱ)/g VSS의 값을 보였다. 이러한 미생물의 EPS의 흡착능은 pH와 칼슘이온의 영향을 많이 받았으며, 메탄산화세균의 FT-IR 분석결과 EPS에는 sulfate ester, pyruvate 등과 같은 작용기와 amino sugar, carboxyl 작용기들이 많이 존재하여 활성슬러지에 비해 중금속의 흡착능이 높은 것으로 사료되었다.X>${\mu}_{max,A}$는 최대암모니아 섭취률을 이용하여 구한 결과 $0.65d^{-1}$로 나타났다.EX>$60%{\sim}87%$가 수심 10m 이내에 분포하였고, 녹조강과 남조강이 우점하는 하절기에는 5m 이내에 주로 분포하였다. 취수탑 지점의 수심이 연중 $25{\sim}35m$를 유지하는 H호의 경우 간헐식 폭기장치를 가동하는 기간은 물론 그 외 기간에도 취수구의 심도를 표층 10m 이하로 유지 할 경우 전체 조류 유입량을 60% 이상 저감할 수 있을 것으로 조사되었다.심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전

• Resources Recycling
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• v.19 no.3
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• pp.24-32
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• 2010

In the present work, a new separation system with rotating rakes has been developed to separate the film-based plastics from the recyclable materials, and environment assessment is also carried out during operation of the device. Capacity of the device was about 5.3 ton/hr at a rakes rotation speed of 26.0 rpm (the number of rakes in the 1st, 2nd and 3rd trials were 39, 52 and 48, respectively) and a belt conveyor speed of 38.5m/min, which satisfied the initial design capacity (5.0 ton/hr). Recovery ratio and purity of the plastic films were 92.6% and 96.5%, respectively at a rotation speed of 28 rpm. The levels of noise, vibration and particulate emission were below material standard regulatory limits. Plastic refused fuel (RPF) was also prepared with the recovered films. The calorific value and chlorine content of the prepared RPF were 9,740 kcal/kg and 0.18%, respectively which satisfy the first grade quality specification of the Korean RPF standard. As a result of this work, recovery of energy resources from the municipal solid waste is possible by adopting the developed separation device.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10c
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• pp.246-251
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• 2006

마이크로어레이 실험은 수 천에서 수 만개의 유전자 발현 결과를 동시에 측정할 수 있어 질병의 발현 형질 분류 등에 유용하게 이용되고 있다. 그러나 마이크로어레이 실험은 동일한 플랫폼의 실험이라 할지라도 환경 등에 따라 그 실험 결과에 차이가 나는 등 오차를 항상 포함하고 있다. 또한 마이크로어레이 실험은 아직 고가의 실험으로 분류되어 다수의 샘플에 대한 반복 실험 결과를 얻기 어려운 상황이다. 따라서 이종의 플랫폼, 데이터 포맷, 정규화 기법 등이 서로 다른 데이터를 효율적으로 통합하여 유용한 정보를 추출하는 새로운 방식의 개발이 필요하다. 본 논문은 이와 같은 문제를 해결하기 위한 기초 단계 연구 결과이다. 마이크로어레이 실험 데이터로부터 통계적 방법을 이용하여 유의(informative) 유전자를 추출하고 유전자 온톨로지(Gene Ontology : GO)와의 연계를 통하여 유전자 정보의 기능적 분류 결과를 사용자에게 제공하는 유전자 기능 분석 시스템의 설계 및 구현 방안을 보인다. 본 시스템의 실험방법에서는 3-Fold Filtering 기법을 통하여 발현 차가 큰 유전자를 추출하고, t-검정 기법에 의하여 이들 유전자를 순위화 하였으며, 이 중 상위 100개의 유전자를 유의 유전자로 추출하였다. 다음, 이 들 유의 유전자의 t-검정 값을 GO의 유전자 기능을 나타내는 해당 텀 (term)에 가중치로 부과하여 각 유전자들과 기능적으로 연관성이 높은 텀들을 추출한다. 또한 본 연구의 유효성을 검증하기 위하여 본 시스템에 의한 마이크로어레이 데이터 분석 결과를 전문가에 의한 유전자 기능 분석 결과와 비교한다.투명성 있는 서비스를 제공하고 높은 신뢰성과 안정성이 확보될 수 있도록 구성하고자 한다. Query 수행을 여러 서버로 분산처리하게 함으로써 성능에 대한 신뢰성을 향상 시킬 수 있는 Load Balancing System을 제안한다.할 때 가장 효과적인 라우팅 프로토콜이라고 할 수 있다.iRNA 상의 의존관계를 분석할 수 있었다.수안보 등 지역에서 나타난다 이러한 이상대 주변에는 대개 온천이 발달되어 있었거나 새로 개발되어 있는 곳이다. 온천에 이용하고 있는 시추공의 자료는 배제하였으나 온천이응으로 직접적으로 영향을 받지 않은 시추공의 자료는 사용하였다 이러한 온천 주변 지역이라 하더라도 실제는 온천의 pumping 으로 인한 대류현상으로 주변 일대의 온도를 올려놓았기 때문에 비교적 높은 지열류량 값을 보인다. 한편 한반도 남동부 일대는 이번 추가된 자료에 의해 새로운 지열류량 분포 변화가 나타났다 강원 북부 오색온천지역 부근에서 높은 지열류량 분포를 보이며 또한 우리나라 대단층 중의 하나인 양산단층과 같은 방향으로 발달한 밀양단층, 모량단층, 동래단층 등 주변부로 NNE-SSW 방향의 지열류량 이상대가 발달한다. 이것으로 볼 때 지열류량은 지질구조와 무관하지 않음을 파악할 수 있다. 특히 이러한 단층대 주변은 지열수의 순환이 깊은 심도까지 가능하므로 이러한 대류현상으로 지표부근까지 높은 지온 전달이 되어 나타나는 것으로 판단된다.의 안정된 방사성표지효율을 보였다. $^{99m}Tc$-transferrin을 이용한 감염영상을 성공적으로 얻을 수 있었으며, $^{67}Ga$-citrate

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.1
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• pp.1-7
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• 2010

PAPR of the pilot symbols can be reduced down by the CAZAC sequence in the SC-FDMA communication system. However, it is very complicated and takes quite a long time to compute the interpolation between the OFDM information symbols for the channel estimation because the pilot data are trasmitted in the block type. Furthermore, situation will be much more serious in the severe fading channel. Actually the pilot insertion of the comb type is much efficient and convenient for the channel estimation since the calculation of the interpolation can be made in the frequency domain symbol by symbol. But, the PAPR will be regrown when the pilot data are inserted with the information data in the comb type. So, in this paper, we like to study the PAPR reduction and comb type pilot assignment for the efficient channel estimation. Unlike the conventional SLM(selected mapping) method requiring the side information, our improved SLM method is to use the phase rotation sequence into information data without rotating phase of pilot. We use different pilot data according to the different phase rotation sequence. From the simulation result, it can be confirmed that when SLM method of 4 phase rotation sequence is used, PAPR is almost same to the block type method without pilot.

• The Journal of the Korea institute of electronic communication sciences
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• v.1 no.2
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• pp.120-126
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• 2006

In this paper, we propose for improving QoS in hospital wireless network using Cellular-IP/PRC(Paging Route Cache) with Paging Cache and Route Cache in Cellular-IP. Although the Cellular-IP/PRC technology is devised for mobile internet communication, it has its vulnerability in frequent handoff environment. This handoff state machine using differentiated handoff improves quality of services in Cellular-IP/PRC. Suggested algorithm shows better performance than existing technology in wireless mobile internet communication environment. When speech quality is secured considering increment of interference to receive in case of suppose that proposed acceptance method grooves base radio station capacity of transfer node is plenty, and most of contiguity cell transfer node was accepted at groove base radio station with a blow, groove base radio station new trench lake acceptance method based on transmission of a message electric power estimate of transfer node be. Do it so that may apply composing PC(Paging Cache) and RC(Routing Cache) that was used to manage paging and router in radio Internet network in integral management and all nodes as one PRC(Paging Router Cache), and add hand off state machine in transfer node so that can manage hand off of transfer node and Roaming state efficiently, and studies so that achieve connection function at node. Analyze benevolent person who influence on telephone traffic in system environment and forecasts each link currency rank and imbalance degree, forecast most close and important lake interception probability and lake falling off probability, GoS(Grade of Service), efficiency of cell capacity in QoS because applies algorithm proposing based on algorithm use gun send-receive electric power that judge by looking downward link whether currency book was limited and accepts or intercept lake and handles and displays QoS performance improvement.

• Journal of KIISE:Software and Applications
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• v.37 no.10
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• pp.788-801
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• 2010

Advancing of mobile device is remarkable, so the research on mobile input device is getting more important issue. There are lots of input devices such as keypad, QWERTY keypad, touch and speech recognizer, but they are not as convenient as typical keyboard-based desktop input devices so input strings usually contain many typing errors. These input errors are not trouble with communication among person, but it has very critical problem with searching in database, such as dictionary and address book, we can not obtain correct results. Especially, Hangeul has more than 10,000 different characters because one Hangeul character is made by combination of consonants and vowels, frequency of error is higher than English. Generally, suffix tree is the most widely used data structure to deal with errors of query, but it is not enough for variety errors. In this paper, we propose fast approximate Korean word searching system, which allows variety typing errors. This system includes several algorithms for applying general approximate string searching to Hangeul. And we present profanity filters by using proposed system. This system filters over than 90% of coined profanities.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.4
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• pp.593-607
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• 2013

The In-Vehicle-Networking(IVN) of modern cars is constituted by an small electronic control device called ECU. In the past, there was no way to be able to access the IVN of a driving car. so IVN has been recognized as a closed environment so there is no need to exist authentication protocol between devices which are to configure the internal network and to communicate with other devices. However, constant improvements made it possible to access the IVN in many different ways as the communication technology evolves. This possibility created a need for device authentication in IVN. HB-Family are representative authentication schemes in RFID environment which has similar restrictions to IVN. In this paper, we propose an implementation method of HB-Family for device authentication between ECU considering ECU has low computing power and the message field of CAN protocol has restricted size of 8 bytes. In order to evaluate the efficiency and availability of the authentication schemes adopted our method, we have evaluated the performance based on DSP-28335 device. Further, it was possible to improve the efficiency rate of at lest 10%, up to 36%, and we then analyze this result in various aspects of the IVN.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.4
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• pp.833-838
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• 2011

RFID system in manufacturing industry is used to collect, categorize, and process the data of products. To install RFID system for a large factory, a large amount of wired data communication network is necessary for RS232 communication. If the installed location of RFID system in the factory is changed or extended, a reinstallment is required for the already installed wired data network. A large amount of time/financial reinvestment is necessary for such reinstallation. By using wireless data communication network, however, the initial installation and reinstallation are very simple. In this paper, we implemented a wireless communication system and RFID system. We used the CC1020 chip for wireless communication system and EM4095 chip for RFID system. CC1020 chip enables highly-reliable data communication, and by setting a simple status register, it can switch between transmitting/receiving status and it can choose the desired frequency of either 400 MHz or 900 MHz. Also, Communication range is 50 m, if external antenna is used. EM4095 is a chip for RFID reader system with the carrier frequency of 125 KHz. This chip can implement the reader system by connecting a small number of components. And EM4100 was used for RFID system. EM4100 is read-only type. Atmega128 is used to control a wireless communication system and RFID system. We confirm that the system can communicate without error up to 50 m from sender. In the paper, the circuit diagram and operation program for CC1020 and RFID system are presented. The system used in the experiment is shown in pictures, and the data movement pattern of CC1020 is shown in the diagram, and the performance of each transmission method is presented.

• Journal of KIISE:Software and Applications
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• v.31 no.9
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• pp.1233-1245
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• 2004

Though biometrics to authenticate a person is a good tool in terms of security and convenience, typical authentication algorithms using biometrics may not be executed on resource-constrained devices such as smart cards. Thus, to execute biometric processing on resource-constrained devices, it is desirable to develop lightweight authentication algorithm that requires only small amount of memory and computation. Also, among biological features, face is one of the most acceptable biometrics, because humans use it in their visual interactions and acquiring face images is non-intrusive. We present a new face authentication algorithm in this paper. Our achievement is two-fold. One is to present a face authentication algorithm with low memory requirement, which uses support vector machines (SVM) with the feature set extracted by genetic algorithms (GA). The other contribution is to suggest a method to reduce further, if needed, the amount of memory required in the authentication at the expense of verification rate by changing a controllable system parameter for a feature set size. Given a pre-defined amount of memory, this capability is quite effective to mount our algorithm on memory-constrained devices. The experimental results on various databases show that our face authentication algorithm with SVM whose input vectors consist of discriminating features extracted by GA has much better performance than the algorithm without feature selection process by GA has, in terms of accuracy and memory requirement. Experiment also shows that the number of the feature ttl be selected is controllable by a system parameter.