• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.88-94
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• 2016

The simultaneous biodegradation between MTBE (Gasoline additives) and BTEX (Benzene, Toluene, Ethyl-benzene, o-Xylene, m-Xylene, p-Xylene) was achieved within a competitive inter-relationship, with not only electron accepters such as nitrate, sulfate, and iron(III) without oxygen, but also with electron donors such as MTBE and BTEX. Preexisting indigenous microorganisms from a domestic sample of gasoline contaminated soil was used for a lab-scale batch test. The result of the test showed that the biodegradation rate of MTBE decreased when there was co-existing MTBE and BTEX, compared to having just MTBE present. The growth of indigenous microorganisms was not affected in the case of the MTBE treatment, whereas the growth of the microorganisms was decreased in combined MTBE and BTEX sample. This may indicate that an inhibitor related to biodegradation when BTEX and MTBE are mixed will be found. This inhibitor may be found to retard the anaerobic conditions needed for efficient breakdown of these complex carbon chain molecules in-situ. Moreover, it is also possible that an unknown competitive reaction is being imposed on the interactions between MTBE and BTEX dependent on conditions, ratios of mixture, etc.

• Asian-Australasian Journal of Animal Sciences
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• 제14권8호
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• pp.1098-1105
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• 2001

There is little information on smallholder dairy farming in Zimbabwe. With such inadequate knowledge, no meaningful decisions on how to improve these systems can be made. A study was, therefore, carried out in Nharira communal area and Lancashire small-scale commercial area to provide information on the viability of dairy farms. This paper is based on data obtained through participatory monitoring of 13 smallholder dairy farms in 1996 and 1997. All the four farms in Lancashire were found to be viable in both years. In Nharira, two out of the nine farms in 1996 and three farms in 1997 failed to break even. There were considerable inter-farm differences in the contribution of milk sales towards total income from dairy farming, ranging from 41% to 99% in Nharira and 71% to 81% in Lancashire in 1996. Corresponding estimates in 1997 were 51-95% and 72-78%, respectively. Expenses on cattle feeds contributed 36-84% in 1996 and 37-80% in 1997 towards total variable costs in Nharira. In Lancashire, the respective estimates were 15-33% and 22-36%. Seven out of the nine studied farms in Nharira and three out of four in Lancashire realized higher gross margin (GM) in 1997 than in 1996. All these farming households had conserved considerable amounts of farm-grown feeds. It was concluded that feed costs, number of cows and sizes of land holdings were the main factors determining viability of smallholder dairy farming. The major challenge to smallholder dairy farming in Nharira, in particular, was to develop low-cost feeding strategies.

• 한국정보처리학회논문지
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• 제5권5호
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• pp.1300-1310
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• 1998

Web 정보 시스템은 많은 수의 정적 HTML 문서들과 동적 CGI 응용 프로그램들로 구성된다. 많은 수의 HTML 문서는 문서관리의 어려움이 있을 뿐 아니라 문서의 내부정보 및 문서간의 정보 일관성을 유지하기가 쉽지 않다. 본 논문에서는 계층적 형식문서 체계의 정보관리 시스템과 관리자 계층에 의한 효율적인 시스템 관리 기법을 제안한다. 구현의 예로서는 계층화된 관리자 기능을 제공하는 대규모 Web 정보 시스템을 구축한다. 이러한 Web 정보시스템 관리는 상시 발생하는 정보를 정보의 발생시점에서 각 관리자가 능동적으로 대처할 수 있을 뿐 아니라 정보의 구조 변경에도 융통성이 있는데, 이 방법은 대규모 Web 정보 시스템 구축과 관리에 효율적이다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 가을학술발표회 논문집
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• pp.55-60
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• 1992

Hydraulically filled ground is formed by the settling of soil grains from the mixture of soil grains and water. It was generally known that the settling speed of the soil grains in governed by Stokes low. In the case of clayed dredged material, the shape of soil grains is not round, the surface of the soil grains is relatively large compared to the weight of soil grains and inter-grain ionic force is relatively large compared to the wight of soil grains. By this reason the settling and consolidation behavior of hydraulically filled quite different from that of Stokes law. This study investigated the settling and consolidation behavior of hydraulically filled materials of Yeochon industrial complex by large scale laboratory settling & consolidation container. The test results showed tat actual settling speed of soil grains in quite large compared to that of Stokes law. It was turned out that this phenomenon was due to the aggregation of soil grains. Also, it was truned out that the void ration and water content after the completion of settling process was 8.7 and 322% respectively. The consolidtion settlement of clayey hydraulic fill material was predicated better by "incremental small strain" consolidation concept than classical Terzaghj's consolidation concept (infinitesimal strain).

• Journal of Preventive Medicine and Public Health
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• 제33권1호
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• pp.51-55
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• 2000

Objectives . In large-scale field trials, randomization by cluster is frequently used because of the administrative convenience, a desire to reduce the effect of treatment contamination, and the need to avoid ethical issues that might of otherwise arise. Cluster randomization trials are experiments in which intact social unit, e.g., families, schools, cities, rather than independent individuals are randomly allocated to intervention groups. The positive correlation among responses of subjects from the same cluster is in matter in cluster randomization. This thesis is to compare the results of three randomization methods by standard error of estimator of treatment effect. Methods : We simulated cholesterol data varing the size of the cluster and the level of the correlation in clusters and analyzed the effect of cholesterol-lowering agent. Results : In intra-cluster randomization the standard error of the estimator of treatment effect is smallest relative to that in inter-cluster randomization and that in individual randomization. Conclusions : Infra-cluster randomization is the most efficient in its standard error of estimator of treatment effect but other factor should be considered when selecting a specific randomization method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권3호
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• pp.490-508
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• 2013

One of the most important scalability issues facing the current Internet is the rapidly increasing rate of BGP updates (BGP churn), to which route flap and path exploration are the two major contributors. Current countermeasures would either cause severe reachability loss or delay BGP convergence, and are becoming less attractive for the rising concern about routing convergence as the prevalence of Internet-based real time applications. Based on the observation that highly active prefixes usually repeatedly explore very few as-paths during path exploration, we propose a router-level mechanism, Path Exploration Aggregation (PEA), to scale BGP without either causing prefix unreachable or slowing routing convergence. PEA performs aggregation on the transient paths explored by a highly active prefix, and propagates the aggregated path instead to reduce the updates caused by as-path changes. Moreover, in order to avoid the use of unstable routes, PEA purposely prolongs the aggregated path via as-path prepending to make it less preferred in the perspective of downstream routers. With the BGP traces obtained from RouteViews and RIPE-RIS projects, PEA can reduce BGP updates by up to 63.1%, shorten path exploration duration by up to 53.3%, and accelerate the convergence 7.39 seconds on average per routing event.

• 대한통합의학회지
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• 제7권4호
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• pp.151-159
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• 2019

Purpose : This study aimed to evaluate the effects of sitting questionmark exercise (SQE) and brugger's relief exercise (BRE) on pain, ROM, proprioception, NDI in 60 Patients with Chronic Cervical Pain (CCP). Methods : In this study the VAS and NDI were used to investigate changes in pain and disability with SQE and BRE. The pre and post intervention intra group differences were analysed with a paired t-test for mean values, and the inter group differences were analyzed with an independent t-test for mean values. Results : The pain of both of groups was lowered with statistical significance. Pain of SQE group is lower than that of BRE group with statistical significance. ROM in both groups was improved, but there is no significant difference between two groups. NDI in both of groups were significantly decreased after the intervention, but there was no significant difference between groups. there was NDI ratio (%) significant difference between each groups. Conclusion : SQE intervention may be considered a more effective clinical approach for reducing pain and restoring proprioception in patients with CCP.

• 농촌계획
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• 제13권4호
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• pp.43-51
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• 2007

The propose of this paper is to study a theory on the research of mountain village region in korea of globalization age. The theory of this study is over-depopulation region study, endogenous regional development theory and resident organization, localities and new regional studies The case of over-depopulation region study, which population and land use of mountain village region due to urbanization and industrialization are changed by external factors. However, the case of some region is changed by internal factors of community residents. The endogenous regional development theory and have approached by investment policy of authorities of the mountain village region development and resident organization. The development of mountain village region have to described simultaneously both behavior strategy of community residents and investment policy of the authorities. According to localities and new regional studies, which agricultural products of mountain village region is extended to big-scale city by the progress transportation-communication and globalzation So, the research of mountain village region have to explained together intra with inter region. In the future, the research of mountain village region has to described all of case of over-depopulation region study, endogenous regional development theory, localities and new regional studies.

• 한국측량학회지
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• 제20권4호
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• pp.405-413
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• 2002

연속지적도를 제작하기 위해서는 합리적으로 도면의 신축보정, 도곽접합, 행정구역 접합, 축척 간 접합 등을 처리할 수 있는 기준의 설정이 무엇보다 중요한 선결 과제라 할 수 있다. 본 연구는 지번부여지역단위 임의 도곽으로 작성된 임야도의 행정구역간 경계의 필지접합 및 지적임야도 접합에 2차원 비선형좌표변환방법인 사영투영과 부등각사상변환방법 및 다항식변환방법을 도입하여 행정구역 경계선상 또는 임야사정선상 굴곡점을 기준점으로 하여 2차원 좌표변환계수를 추출하고 연속지적도 작성을 위한 도면접합에 좌표변환방법의 활용을 시도하였다.

• Journal of Korean Society for Atmospheric Environment
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• 제20권E2호
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• pp.69-75
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• 2004

In this study, thin film gas sensor based on tin oxide was fabricated to examine its characteristics. Target gas is acetonitrile ($CH_3$CN) which is a blood simulant for the chemical warfare agent. Sensing materials are SnO$_2$ SnO$_2$/Pt, and Sn/Pt with thickness from 1000 to 3000 $\AA$. The sensor consists of a sensing electrode with inter-digit (IDT) type in front side and a heater in rear side. Resistance changes of sensing materials are monitored on real time basis using a data acquisition board with a 12-bit analog to digital converter. Sensitivities are measured at different operating temperatures also with different gas concentrations and film thickness. The high sensitivity is obtained for Sn (3000 $\AA$)/Pt (30 $\AA$) at 30$0^{\circ}C$ for 3 ppm. Response and recovery times were about 40 and 160 s, respectively. Repetition measurements showed very good results with $\pm$3% in full scale range.