• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.287-294
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• 2021

In order to expand facility agriculture and reduce greenhouse construction costs in reclaimed land, a greenhouse foundation method that satisfies economic feasibility and structural safety at the same time is required. As an alternative, the allowable bearing capacity and settlement were reviewed when the DCM(Deep cement mixing) method was applied among the soft ground reinforcement methods. To examine the applicability of the greenhouse foundation, the allowable bearing capacity and settlement were calculated by applying the theory of Terzaghi, Meyerhof, Hansen, and Schmertmann. In case of the diameter of 800mm and the width and length of the foundation of 4m, the allowable bearing capacity was 179kN/m² and the settlement was 7.25mm, which satisfies the required bearing capacity and settlement standards. The calculation results were verified through FEM(Finite element method) analysis using the Mohr-Coulomb material model. The allowable bearing capacity was 169kN/m² and the settlement was 2.52mm. The bearing capacity showed an error of 5.6% compared to calculated value, and the settlement showed and error of 65.4%. Through theoretical calculations and FEM analysis, it was confirmed that the allowable bearing capacity and settlement satisfies the design criteria as a greenhouse foundation when the width and length of the foundation were 4m. Based on the verified design values, it is expected to be able to present the foundation design criteria for greenhouses through empirical tests such as bearing capacity tests and long-term settlement monitoring.

• Journal of the Korean association of regional geographers
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• v.21 no.3
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• pp.427-449
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• 2015

Network governance can be defined as collaborative process to develop a new socio-political order through civil society centered networking with government and market, and the term 'collaborative governance' can be used in a sense that the basis of governance is collaborative process. In particular, it can be stressed that collaborative governance between regions need double collaborative processes, that is, collaboration between local governments and collaboration between local government and local civil society within a region. Yet, the collaboration as a core element of collaborative governance should not be seen as a pure normativity presupposing confidence and reciprocity, but as a strategy based on competition and antagonism. The normativity implied in the concept of collaborative governance may not realized in actual process, and tends to be mobilized as a rationale for justifying neoliberal strategies. In order to overcome such limits of collaborative governance, the concept of collaborative governance should be reconstructed. This paper suggests that collaborative governance can be seen as hegemonic governing process in a Gramcian sense operating in the government plus civil society, and that, radicalizing Ostrom's concept, it also can be seen as a governing process producing polycentricity by self-regulating subjects. Finally, collaborative governance between regions needs expansion of material basis for economic complementarity and construction of infrastructure as well as a discursive process in order to enhance connectivity between them.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.433-433
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• 2011

수자원 계획 및 관리를 위한 지표 자료로서 일유량은 매우 유용하기 때문에 정확한 일유량 산정의 문제는 매우 중요하다. 그러나 우리나라의 경우 조석이나 배수 갑문 혹은 보 등에 의한 배수 영향으로 인해 수위-유량관계곡선식만으로 정상적인 유량산정이 어려운 지점이 다수 존재한다. 특히, 한강대교 지점과 같이 조석영향 구간에서 수위-유량관계곡선식에 의해 산정된 일유량은 자료에 대한 곡선식의 적합도 문제로 그 정확도가 매우 낮았다. 최근 자동유량측정에 의해 시간단위 이하의 실시간 유량이 생산되고 있고 이를 이용하여 일유량을 환산하고 있어 과거에 비해 보다 정확한 일유량 산정이 가능해 졌다. 그러나 신뢰도 있는 일유량을 안정적으로 제공하기 위해서는 보다 다양한 조건을 고려한 비교 검증 연구가 요구되는 실정이다. 이러한 배경에서 본 연구에서는 한강대교 지점과 같이 조석영향을 받는 지점의 일유량 산정방법 및 산정개념에 따른 유황의 차이와 적정성을 평가하여 보았다. 각 산정방법 및 산정개념 별로 산정된 일유량을 통해 유황을 산정하여 한강대교 지점의 일유량 산정방법에 대한 적정성을 평가하고 적절한 유황산정을 위한 목적별 대안을 제시하였다. 산정방법 별로는 기존의 수위-유량관계 곡선식으로 변환된 자료, 자동유량측정자료, 그리고 자동유량측정자료에서 조석성분을 제거한 순수 유출성분자료를 이용하여 일유량을 산정하였고, 이를 이용하여 산정된 유황에 대한 비교 분석을 실시하였다. 수위-유량관계곡선식에 의한 일유량은 수문조사연보의 자료를 이용하였고 자동유량자료를 이용한 일유량은 시자료를 평균하여 일유량으로 환산하는 방법을 사용하였다. 자동유량 자료에서 조석성분을 제거한 순수 유출성분의 추출은 웨이블릿 변환(wavelet transform)을 이용하였다. 각 방법별로 산정된 일유량을 비교한 결과 수위-유량관계곡선식에 의해 산정된 일유량이 자동 유량자료로 산정된 일유량에 비해 전반적으로 크게 나타났고, 2009년 한해 동안의 유출용적을 비교해 본 결과 18%정도 더 크게 산정되었다. 산정개념에 따른 비교에서는 조석성분 유량의 유효성 여부에 따른 유황을 비교하였으며, 조석성분 유량도 실효적 유량으로 간주한 경우 이론적 확률 분포형에 적합시켜 산정한 평균 갈수량은 15.7 ��/s(동절기 이상 거동기간인 2009년 11월 17일-12월 12일 기간을 제외하고 산정된 결과이나 불확실성은 잔존)에서 $53.2m^3/s$로 증가하였다. 따라서 유지유량의 목적상 경관용수나 생태용수가 중요한 지점으로 조석성분 유량이 이에 유효하다면, 유황산정을 위한 한강대교 지점의 일유량 산정방법은 다양한 목적에 비추어 추가적인 분석 검토가 필요할 것으로 판단된다.

• The KIPS Transactions:PartC
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• v.14C no.5
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• pp.417-424
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• 2007

Mesh networks using WLAN technology have been paid attention as a key wireless access technology. However, many technical issues still exist for its successful deployment. One of those issues is the routing problem that addresses the path setup through a WLAN mesh network for the data exchanges between a station and a wired network. Since the characteristics of a WLAN mesh network can be very dynamic, the use of single routing protocol would not fit for all environments whether it is reactive or proactive. Therefore, it is required to develop an adaptive routing protocol that modifies itself according to the changes in the network parameters. As a logical first step for the development, an analytical model considering all the dynamic features of a WLAN mesh network is required to evaluate the performance of a reactive and a proactive routing scheme. In this paper, we propose an analytical model that makes us scrutinize the impact of the network and station parameters on the performance of each routing protocol. Our model includes the size of a mesh network, the density of stations, mobility of stations. and the duration of network topology change. We applied our model to the AODV that is a representative reactive routing protocol and DSDV that is a representative proactive routing protocol to analyze the tradeoff between AODV and DSDV in dynamic network environments. Our model is expected to help developing an adaptive routing protocol for a WLAN mesh network.

• Korean Journal of Culture and Social Issue
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• v.13 no.3
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• pp.23-63
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• 2007

The purpose of this study is to develop and verify the Relational Self Scale(RSS). Based on the theoretical assumptions which relational self is multi-dimensional and constructed in social contexts, 10 categories with 102 items were yielded. In the process of content analysis, item analysis, exploratory factor analysis and correlation analysis by administering 102 items to korean adults, 31 items with 7 factors are extracted. The 7 factors are consisted of 'avoidance of relation', 'consciousness of others', 'agency', 'instrumental relation', 'empathy-care', 'perceived support from relation' and 'over-dependency to relation'. Next, Confirmatory factor analysis was conducted with 649 korean adults aged from 20's to 60's. The results of confirmatory factor analysis showed the RSS as a valid scale. The 7 factors of the RSS fitted well with men and women. The internal consistency of the RSS was proved to be acceptable. The latent mean analysis indicated that the relational self was not significantly different between men and women at 7 factors. Correlation analysis showed that the construct of relational self was significantly related to relational self-construal, self-esteem and attachment to parent and intimacy person. This study has implication in that relational self is defined and assessed as multi-dimensional construct, and that by administering RSS it is possible to evaluate distinctive korean people's relational self.

• Journal of Nutrition and Health
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• v.48 no.5
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• pp.407-418
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• 2015

Purpose: Given that the indicators related to chronic diseases are important to evaluating goals of the national health policy, the aim of this study was to develop dietary behavior items available in the Korea National Health and Nutrition Examination Survey. Methods: The dietary behavior items were developed based on the literature reviews, need assessment of the field, expert focus-group interviews, and expert advisory meeting. Questions for each dietary behavior item were developed by reflecting on environmental, personal, and behavior factors of the ecological frame and then revised through expert focus-group interview and expert advisory meeting. The understanding and reliability of the developed questionnaire were assessed by cognitive interview and test-retest reliability. Results: The developed items were sodium and salt intake, added and simple sugar intake, enough time to consume a meal for all ages, caffeine drinks and fresh/healthy food intake for children and adolescents, and limited dietary intake, fresh/healthy food intake for seniors. In most questions except some questions on sodium and salt intake, subjects understood over 70% and consistency of responses based on the kappa values was acceptable. Conclusion: Developed dietary behavior items are expected to be useful for evidence-based nutrition policy, interventions and research targeting dietary patterns through investigating and monitoring dietary behavior patterns.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.3
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• pp.142-154
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• 2011

This study predicted the probability of corrosion initiation of reinforced concrete tunnel boxes structures using the Monte Carlo Simulation. For the inner wall and outer wall in the tunnel boxes, exposed to airborne chloride ion and seawater directly respectively, statistical values of parameters like diffusion coefficient D, surface chloride content $C_s$, cover depth c, and the chloride threshold level $C_{lim}$ were examined from experiment or literature review. Their average values accounted for $3.77{\times}10^{-12}m^2/s$, 3.0% by weight of cement, 94.7mm and 45.5mm for outer wall and inner wall, respectively, and 0.69% by weight of cement for D, $C_s$, c, and $C_{lim}$, respectively. With these parametric values, the distribution of chloride contents at rebar with time and the probability of corrosion initiation of the tunnel boxes, inner wall and outer wall, was examined by considering time dependency of chloride transport. From the examination, the histogram of chloride contents at rebar is closer to a gamma distribution, and the mean value increases with time, while the coefficient of variance decreases with time. It was found that the probability of corrosion initiation and the time to corrosion were dependent on the time dependency of chloride transport. Time independent model predicted time to corrosion initiation of inner wall and outer wall as 8 and 12 years, respectively, while 178 and 283 years of time to corrosion was calculated by time dependent model for inner wall and outer wall, respectively. For time independent model, the probability of corrosion at 100 years of exposure for inner wall and outer wall was ranged 59.5 and 95.5%, respectively, while time dependent model indicated 2.9 and 0.2% of the probability corrosion, respectively. Finally, impact of $C_{lim}$, including values specified in current codes, on the probability of corrosion initiation and corrosion free life is discussed.

• Archives of design research
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• v.19 no.4 s.66
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• pp.41-50
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• 2006

It is generally regarded a design system in post-industrial society, which products designed by in-house designers or design consultancy are manufactured in factory and distributed in market for the consumer. Although it is treated an old design system in traditional society, the traces of vernacular design has been remaining in the state of adopted to the periodical needs in these days, also proving the attribute of design culture to constitute human's material environment as well as existing design systems. There were discovered various design artifacts in daily surroundings vary from the established design in several manners, user modifications or manufactures in everyday lives formalized them. It was approached a case study that analyze the changes of artifact configuration and designer/user context and creation process of the non-professional design artifacts, Creativity Template Theory and ACM(Artifact Context Model) have been utilized for the analysis model. From the analysis result, It assume that the everyday artifacts may be ordinary but extra-ordinary including particular ideas and identity represented by everyday designers or users. Beside these characteristics induce the potentiality that reflect on creative motives for the designers or a complementary artifact generator filling up with drawbacks in established design system. The everyday design domain, various explorations and alternatives are made, is seems to be another design practice domain dissimilar to the one in the industry-based design. Moreover it provides an more easily accessability for the approaching user-friendly design, user customization because they conduct the reliable modeling of consumer and end-user. Finally, based on the exploratory study regarding interpretation of context and configuration in the everyday artifacts, new approach for the design process and design education through more detailed cognitive modeling of everyday designers will be a further study.

• The Journal of the Acoustical Society of Korea
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• v.22 no.8
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• pp.652-659
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• 2003

High-frequency(40∼120 kHz) reflection loss measurements on the water-sandy sediment with a flat interface were conducted in a water tank for various grazing angles. The water tank(5×5×5 m) was filled with a 0.5 m-thick-flat bottom of 0.5ø-mean-grain-size sand. Reflection losses, which were experimentally obtained as a function of grazing angle and frequency, were compared with the forward loss model, APL-UW model (Mourad & Jackson, 1989). For frequencies below 60 kHz, the observed losses well agree with the reflection loss model, however, in cases for frequencies above 70 kHz, the observed losses are greater by 2∼3 dB than the model results. The model calculation, which does not fully account for the vertical scale of roughness due to grain size, produce less bottom losses compared to the observations that correspond to large roughness based on the Rayleigh parameter in the wave scattering theory. In conclusion, for the same grain-size-sediment, as frequencies increase, the grainsize becomes the scale of roughness that could be very large for the frequencies above 70 kHz. Therefore, although the sea bottom was flat, we have to consider the frequency dependence of an effect of roughness within confidential interval of grain size distribution in reflection loss model.

• Journal of the Korean earth science society
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• v.24 no.3
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• pp.150-159
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• 2003

This study suggests methods of assessing scientific creativity and developing items, which can be achieved when both earth science knowledge and general creativity are applied at the same time. According to the results of this study, the cognitive ability gaps between creativity and scientific creativity were clearly defined by the terms' operational definition. Four factors in the Subcategory Of Scientific Creativity-fluency, flexibility, elaboration, and originality-were selected, and the possibility of developing items out of these factors was discovered. The operational definitions of the four factors were given and the criteria for assessment and scoring were set. The validity, reliability, discrimination, and difficulty, which were the conditions required for the assessment instruments, were verified through three field trials of inputting the assessment instruments for scientific creativity. The assessment instruments were composed of 8 items with 2items for each factor. The average item fitness index obtained was 0.99, Cronbach , the item inter-consistency was 0.79,the inter-rater reliability of each item was 0.78, the inter-rater reliability of each factor was 0.75, the item discrimination power was 0.19, and the item difficulty was 0.00. Because the results were within the permitted limit of the conditions required for assessment instruments, the assessment instruments developed for scientific creativity in this study can be said to be very favorable.