• 디지털콘텐츠학회 논문지
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• 제6권1호
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• pp.19-24
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• 2005

모바일 서비스는 언제, 어디서나 누구에게나 유연한 서비스를 제공할 수 있으며, 이러한 특징을 기반으로 기존의 유선 서비스로는 접근이 제한되는 곳까지 보편적 서비스를 제공함으로써 서비스의 확대와 함께 상호 연계성을 더욱 향상시킬 수 있다. 음성 통화료만으로 매출의 한계를 절감한 이동통신사들은 무선인터넷을 대안으로 보고 이를 집중 육성하였다. 특히 모바일뱅킹, 모바일 게임 등 각종 모바일 서비스를 위한 시스템을 개발하고 다양하고 차별화된 콘텐츠개발에 주력하여 무선인터넷 이용자의 확보에 노력하고 있다. 본 연구에서는 이러한 모바일 서비스를 위한 콘텐츠제작의 한 사례로서 모바일 기반의 전자장부시스템을 제안한다. 이 시스템은 유선 인터넷으로 금전관리를 하였을 때의 단점을 보완한 것으로서 휴대폰을 이용하여 자료를 입력하고 검색 또는 수정이 가능하도록 되어있어 공간과 시간의 제약 없이 언제 어디서나 지출과 수입이 일어난 시점에서 즉시 금전관리를 할 수 있다는 장점이 있다.

• Geomechanics and Engineering
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• 제16권2호
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• pp.125-140
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• 2018

Tianjin, which is located on the west shore of the Bohai Sea, is part of China's Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early $21^{st}$ century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, $C_c$, coefficient of consolidation, $C_v$, and hydraulic conductivity change index, $C_{kv}$, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, $C_a$, is also investigated, and the results show that the ratio of $C_a/C_c$ for Tianjin marine clay can be used to calculate $C_a$ in secondary consolidation settlement predictions.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.62-72
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• 2016

This study investigated the dynamics associated with prolonged ensiling and aerobic deterioration of whole crop corn (WCC) silages and total mixed ration (TMR) silages containing WCC (C-TMR silages) to clarify the differences that account for the enhanced aerobic stability of TMR silages. Laboratory-scale barrel silos were randomly opened after 7, 14, 28, and 56 d of ensiling and were subjected to analyses of fermentation quality, microbial and temperature dynamics during aerobic exposure. WCC and C-TMR silages were both well preserved and microorganisms were inhibited with prolonged ensiling, including lactic acid bacteria. Yeast were inhibited to below the detection limit of 500 cfu/g fresh matter within 28 d of ensiling. Aerobic stability of both silages was enhanced with prolonged ensiling, whereas C-TMR silages were more aerobically stable than WCC silages for the same ensiling period. Besides the high moisture content, the weak aerobic stability of WCC silage is likely attributable to the higher lactic acid content and yeast count, which result from the high water-soluble carbohydrates content in WCC. After silo opening, yeast were the first to propagate and the increase in yeast levels is greater than that of other microorganisms in silages before deterioration. Besides, increased levels of aerobic bacteria were also detected before heating of WCC silages. The temperature dynamics also indicated that yeast are closely associated with the onset of the aerobic deterioration of C-TMR silage, whereas for WCC silages, besides yeast, aerobic bacteria also function in the aerobic deterioration. Therefore, the inclusion of WCC might contribute to the survival of yeast during ensiling but not influence the role of yeast in deterioration of C-TMR silages.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.274-277
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• 2008

Rekeying is the process of changing the encryption key of an ongoing communication. The main objective is to limit the amount of data encrypted with the same key. The IEEE 802.11 standard defines the Wired Equivalent Privacy, or WEP, encapsulation of 802.11 data frames. MAC at sender encrypts the payload (frame body and CRC) of each 802.11 frame before transmission using RC4 stream cipher. MAC at receiver decrypts and passes data to higher level protocol. WEP uses symmetric key stream cipher (RC4) where same key will be used for data encryption and decryption at the sender and the receiver. WEP is not promising with the advancement of the wireless technology existing today. We propose to use the existing information to define the security attributes. This will eliminate the steps that regenerated keys have to be sent to each other over certain period. The rekeying scheme is according to the number of bytes transmitted. Therefore, even the attacker has recorded the packets, it will be insufficient information and time for the attacker to launch the attacks as the key is not deterministic. We develop a packet simulation software for packet transmission and simulate our propose scheme. From the simulation, our propose scheme will overcome the weak WEP key attack and provide an alternative solution to wireless packet transmission. Besides that, our solution appears to be a software approach where only driver updates are needed for the wireless client and server.

• 농촌계획
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• 제15권4호
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• pp.11-17
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• 2009

Rural Amenity Design Competition is opened every year since 2003 having an intention of improving spatial design and planning of rural area through developing values of rural amenity resources and applying in that area. The subject of this competition is broad and there's no limit in locations so that various solutions and original ideas could be proposed. This research examined 165 prizewinning works of the competition and analyzed the locations and areas, aims, main resources, spatial planning contents and experience programs to find out trends of rural spatial design. According to the study, the prizewinning works tends to 1) include spatial plan for an existing village planning, 2) aim rural tourism for citizens and increasement of resident's incomes, 3) develop vegetation and agricultural resources, 4) plan for natural landscape, commercialization of local special productions and agriculture, and 5) propose ecological experience programs. The same theme of the competition repeated every year had led to advanced design skills but also a stagnant of design contents. A subject and a main goal of the Rural Amenity Design Competition should be departmentalized each time hereafter to make for the weak points and propose progressive direction for the rural spatial design.

• 환경위생공학
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• 제23권4호
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• pp.37-44
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• 2008

In this study we developed the analytical methods for the determination of three neurotoxin; anatoxin-a, saxitoxin and neosaxitoxin using HPLC/FLD system and this analytical methods were applied to real sample; algae culture and algae extracts. For the HPLC/FLD analysis of anatoxin-a samples were concentrated on WCX(Weak Cation Exchanger) SPE and then anatoxin-a in concentrate was derivatized with NBD-F solution. Supernatant was injected on HPLC system. For the HPLC/FLD analysis of saxitoxin and neosaxitoxin samples were separated on the column and then derivatizied by post column reactor for fluorescen detection. For post column reaction of saxitoxin we feed two kinds of reaction solution; Oxidizing Reagent of which composition was periodic acid(7mM) in 50mM potassium phosphate buffer, pH 9 and acidifying reagent of which Composition was 0.5M acetic acid. The LOD value for anatoxin-a, saxitoxin and neosaxitoxin in HPLC/FLD method was 24.3 ng. $35{\mu}g/L$, $27{\mu}g/L$ respectively. We determined the anatoxin-a content of lyophilized anabaena flos-aquae and $20{\mu}g/g$ d.w. of anatoxin-a was detected. We analyzed saxitoxin and neosaxitoxin in algae culture media and extracts of lypopyllized algal cell cultured and that of Deachung reservior. Saxitoxin and neosaxitoxin in real sample were below the limit of detection. Although there are various water treatment processes for removing neurotoxins were suggested no process give simultaneous and complete removal of neurotoxins. It was cocluded that nanofiltration which reject material by size can be a process for removal of neurotoxins.

• 한국콘텐츠학회논문지
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• 제10권12호
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• pp.181-189
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• 2010

우리나라에서 전통 공예는 중요무형문화재로 지정 보호되고 있기는 하지만 현대 생활에서는 그 활용도가 높지 않다. 그러나 현재 전통문화산업의 전략적 비중이 높아져가고, 문화적 요소가 산업의 경쟁력을 좌우하는 시대가 도래되었다. 또한 전통공예의 활성화에 대한 관심과 요구가 커지고 있으나, 전통공예는 그 특성상 여전히 여러 가지 문제점들을 안고 있다. 따라서 전통공예의 기술보전과 산업적 활용이라는 두 가지 과제를 효과적으로 실천할 수 있는 방안이 다각도로 모색되어야 한다. 이에 본 연구에서는 중요무형문화의 종류 중 전통공예기술을 다양한 각도에서 분류하여 그 특징을 분석함으로써 현대의 실생활에 활용도가 높은 공예기술을 찾아 체계적으로 정리하고자 한다. 그리고 이 연구를 통해 전통 공예기술이 전승이나 보존의 한계에서 벗어나 현대적인 기술로서의 발전 가능성과 다양한 산업화 방안을 모색할 수 있는 가이드 라인이 되고자한다.

• 대한한방소아과학회지
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• 제29권2호
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• pp.59-77
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• 2015

Objectives Medical plant has a big role in Herbal Medicines, and most medical plant has phytoestrogens. Therefore some estrogenic effects have been reported in a lot of Korean Medicine literature. Phytoestrogens should be used carefully in children. The objective of this study is to identify reported phytoestrogenic effects in Herbal Medicines and to evaluate the characteristics of the phytoestrogens in Herbal Medicines. Methods A literature search was done with using 8 databases with a limit of reports until 12/31/2013. The estrogenic effects were summarized by each individual Korean Medicine. The frequency of the phytoestrogens was also investigated depending on the Korean medical categorization by the treatment effect. Results and Conclusions Phytoestrogenic effects were reported in 89 Herbal Medicines. Phytoestrogens were act bidirectionally, and the effect was fairly weak compared to estrogen. Phytoestrogenic effect was variable on different cells and tissues. The most frequent phytoestrogenic effect was in tonifying and replenishing medicinal, the following orders were heat-clearing, exterior-releasing, and blood-activating and stasis-dispelling medicinal. Phytoestrogens were not reported in dampness-resolving, digestant, orifice-opening, emetic medicinal.

• 한국지진공학회논문집
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• 제8권1호
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• pp.17-27
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• 2004

본 연구에서는 할선강성을 사용하여 반복계산을 수행하는 새로운 내진설계법을 개발하였다. 개발한 설계법은 탄성해석을 수행하므로 수치해석의 안정성과 용이성을 갖추고 있으며, 동시에 반복계산으로 구조물의 비탄성 거동을 해석할 수 있으므로 각 부재의 강도 및 연성 요구량을 정확히 예측할 수 있다. 본 연구에서는 제안된 설계법의 절차를 정립하였고, 이를 고려한 컴퓨터 해석/설계 프로그램을 개발하였다. 또한, 제안된 설계법을 사용한 설계예제를 제시하였고, 탄성 혹은 비탄성 해석을 이용한 기존 설계법과의 비교를 통하여 그 장점을 검증하였다. 해석과 설계를 통합적으로 수행하는 제안된 설계법은 설계자의 의도에 따라 부재의 강도 및 연성능력, 강기둥-약보 등과 같은 내진설계전략을 효과적으로 구현할 수 있으며, 초기설계단계에서 각 부재의 크기만이 가정된 구조물에 대하여 반복계산을 수행함으로써 주어진 설계전략을 만족하는 비탄성 강도 및 연성 요구량을 직접적으로 계산할 수 있으므로, 경제적이고 안전한 내진설계가 가능하다.

• Geomechanics and Engineering
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• 제5권4호
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• pp.363-377
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• 2013

Any structure constructed on the earth is supported by the underlying soil. Foundation is an interfacing element between superstructure and the underlying soil that transmits the loads supported by the foundation including its self weight. Foundation design requires evaluation of safe bearing capacity along with both immediate and long term settlements. Weak and compressible soils are subjected to problems related to bearing capacity and settlement. The conventional method of design of footing requires sufficient safety against failure and the settlement must be kept within the allowable limit. These requirements are dependent on the bearing capacity of soil. Thus, the estimation of load carrying capacity of footing is the most important step in the design of foundation. A number of theoretical approaches, in-situ tests and laboratory model tests are available to find out the bearing capacity of footings. The reliability of any theory can be demonstrated by comparing it with the experimental results. Results from laboratory model tests on square footings resting on sand are presented in this paper. The variation of bearing capacity of sand below a model plate footing of square shape with variation in size, depth and the effect of permissible settlement are evaluated. A steel tank of size $900mm{\times}1200mm{\times}1000mm$ is used for conducting model tests. Bearing capacity factor $N_{\gamma}$ is evaluated and is compared with Terzaghi, Meyerhof, Hansen and Vesic's $N_{\gamma}$ values. From the experimental investigations it is found that, as the depth of sand cushion below the footing ($D_{sc}$) increases, ultimate bearing capacity and settlement values show an increasing trend up to a certain depth of sand cushion.