• Title/Summary/Keyword: weak limit

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A study on the System for the Mobile electronic account (모바일 기반의 디지털콘텐츠 사례 전자장부시스템에 관한 연구)

  • Song Eun-Jee
    • Journal of Digital Contents Society
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    • v.6 no.1
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    • pp.19-24
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    • 2005
  • Mobile service is able to offer the elastic service to anyone regardless of the place and the tin. With this characteristics, the ubiquitous service could be also provided even to the place which the access was limited with the existing line service, which could improve the mutual connection and could result in the service extension Mobile communication companies, which realized the limit of sale only by telephone conversation, have made an effort to develop wireless internet with concentration as its alternation. Especially concentrating their effort both to the development of distinctive and various contents and to tin development of system for mobile service such as the mobile banking, mobile game and etc., they have done their best to secure the number of the people using the wireless internet. This study is to propose the electronic account system based on the mobile as a case study of contents production for such a mobile service. This system has its advantage to perform the financial management immediately when the income and outcome happen without limitation of the time and space. The information could be stored, searched and modified by using of the mobile phone for this system was made up for the weak point of the financial management for wired internet.

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Geotechnical characteristics and consolidation properties of Tianjin marine clay

  • Lei, Huayang;Feng, Shuangxi;Jiang, Yan
    • Geomechanics and Engineering
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    • v.16 no.2
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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.

Dynamics Associated with Prolonged Ensiling and Aerobic Deterioration of Total Mixed Ration Silage Containing Whole Crop Corn

  • Wang, Huili;Ning, Tingting;Hao, Wei;Zheng, Mingli;Xu, Chuncheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.1
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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.

A New Rekeying Scheme for 802.11 Wireless Packets Transmission (802.11 무선패킷 전송을 위한 새로운 Rekeying 스킴)

  • Phang, Seong-Yee;They, Yu-Shu;Yang, Chi-Shian;Lee, Hoon-Jae;Lim, Hyo-Taek
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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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.

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A study on design trend in rural amenity planing shown in Rural Amenity Design Competition (농촌 어메니티 환경설계 공모전을 통해 본 농촌환경설계 경향 연구)

  • Kim, Eun-Ja;Kim, Sang-Bum;Yun, Hee-Jeong;Kang, Bang-Hun;Lee, Jeung-Won;Lim, Chang-Su;Lee, Seung-Yeon
    • Journal of Korean Society of Rural Planning
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    • v.15 no.4
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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.

Analysis of Neurotoxins, Anatoxin-a, Saxitoxin in Algae Cultured and Algae in Dam Reservoir and its Water Treatment (배양조류 및 댐 저수지 조체중 신경독소 Anatoxin-a, Saxitoxin류의 분석 및 수처리방안)

  • Kim, Hak-Chul;Choi, Il-Whan
    • Journal of environmental and Sanitary engineering
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    • v.23 no.4
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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.

Traditional Crafts for the use of Modern Technology (전통공예기술의 현대적 활용)

  • NamGoong, Sun;Jeong, Su-Kyoung;Kim, Tai-Ho
    • The Journal of the Korea Contents Association
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    • v.10 no.12
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    • pp.181-189
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    • 2010
  • Crafts in our country designated as an Important Intangible Cultural Property. Are protected, but not being utilized less than in everyday life. But now that the culture industry has important strategic and cultural factors that influence the competitiveness of the industrial era was. So on the activation of traditional crafts growing interest and demand, but the nature of traditional crafts are still several issues that are faced. Of course, for the protection and industrial policies and institutional mechanisms, but not without a very negative and is weak. Therefore, preservation of traditional crafts and industrial use of the technology to effectively carry out two tasks have the policy should be sought from every angle. In this study, the kind of important intangible cultural heritage of the traditional craft techniques from various angles by category, by systematically analyze the characteristics of modern man with the utilization of real-world craftsmanship with the highest tradition of finding and preserving traditional craft skills in the limit popular and can be out of the technology industry as a potential development is proposed.

The Review of the Herbal Medicines with Phytoestrogenic Effect (식물성에스트로겐 작용이 보고된 한약재에 관한 고찰)

  • Lee, Sun Haeng;Kim, Hyung Joong;Lee, Eun Ju;Chang, Gyu Tae
    • The Journal of Pediatrics of Korean Medicine
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    • v.29 no.2
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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.

Direct Inelastic Earthquake Design Using Secant Stiffness (할선강성을 이용한 직접비탄성내진설계)

  • 박홍근;엄태성
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.1
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    • pp.17-27
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    • 2004
  • A new earthquake design method performing iterative calculations using secant stiffness was developed. The proposed design method has the advantages of convenience and stability in numerical analysis because it uses elastic analysis. At the same time, the proposed design method can accurately estimate the strength and ductility demands on the members because it performs the analysis on the inelastic behavior of structure using iterative calculation. In the present study, the procedure of the proposed design method was established, and a computer program incorporating the proposed method was developed. Design examples using the proposed method were presented, and its advantages were presented by the comparisons with existing design methods using elastic or inelastic analysis. The proposed design method, as an integrated method of analysis and design, can address the earthquake design strategy devised by the engineer. such as ductility limit on each member, the design concept of strong column - weak beam, and etc. In addition, through iterative calculations on the structure preliminarily designed only with member sizing, the strength and ductility demands of each member can be directly calculated so as to satisfy the given design strategy. As the result. economical and safe design can be achieved.

Experimental estimate of Nγ values and corresponding settlements for square footings on finite layer of sand

  • Dixit, Manish S.;Patil, Kailas A.
    • Geomechanics and Engineering
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    • v.5 no.4
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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.