• Journal of the Korean Geotechnical Society
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• v.33 no.1
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• pp.57-65
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• 2017

During a construction of embankment, sub base, or retaining wall backfill, the speedy measurement of water content is necessary. In this study, a test method for field determination of water content of soil by the calcium carbide gas pressure (speedy water content measurement method) was evaluated for its reliability and accuracy. Dry oven and microwave oven methods were also used for water content measurement. In the test, weathered granite and Nakdong River sand in the site and kaolinite were used for water content measurement. The mass of 20, 22, 24, 26, 28, and 30 g of soil was respectively tested for 1, 3, and 5 min. The effect of each sample on water content was compared one another and analyzed. As the mass and testing time increased, the water content increased. The amount of soil was more important factor than testing time for the speedy water content measurement. In order to obtain similar result to that of dry oven method, 3 min of testing time with 24 g of soil was necessary for weathered granite classified as SM and 3 min with 30 g for Nakdong River sand classified as SP. For Nakdong River sand with 20-50% of kaolinite, the water content by speedy measurement increased as the clay content increased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.19-24
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• 1978

The differences in Vibrio parahaemolyticus detection ratio were compared between the isolation methods, the Most Probable Number technique and single dilution tube method. During the period from February to October in 1976, 298 samples of sea water, 112 of bottom deposit, 169 of shellfish, and 80 of fish samples collected along the south coastal area of Korea were examined to determine the detection ratio of Vibrio parahaemolyticus. It was often observed that Vibrio parahaemolyticus was detected in higher diluted samples even through negative in lower dilution. Three hundred and forty three samples out of 659 samples submitted to the test by MPN procedure appeared positive for Vibrio parahaemolyticus showing $52\%$ detection ratio. Whereas only 149 samples, corresponding $22.5\%$, were positive for Vibrio parahaemolyticus in the lowest dilution grade. The positive result was $24.5\%$ in the lowest dilution grade and $50\%$ by MPN Procedure in sea water samples, $28.6\%$ and $65.2\%$ in bottom deposit, $22.5\%$ and $56.2\%$ in shellfish and $7.5\%$ and $32.5\%$ fish samples. When tested by triplicate tubes, $61.7\%$ of 149 Vibrio parahaemolyticus positive samples appeared positive in one tube, $28.9\%$ of them were positive in two tubes and $9.4\%$ of them were positive in all three tubes. The detection ratio determined by MPN procedure was more than two times higher than that of single dilution in triplicate tubes.

• Korean Security Journal
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• no.13
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• pp.551-575
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• 2007

한국에서의 경찰제도는 국가경찰의 형태로 운영되어와 획일적이고 중앙집중식의 경찰활동에 대한 거부감이 전반적으로 있어왔다. 그러나 지역주민의 의사에 따른 자율규율에 의한 다원적 민주주의를 실현하고 국민의 기본권을 실질적으로 보장하기 위하여 지난 1995년 지방자치단체의 장과 지방의회 의원의 동시선거가 시행되어 온 이래 10여년이 흘렀다. 그러나 지방자치제도가 시행되기 이전부터 자치경찰제도에 대한 논의는 지속적으로 이루어져 왔다. 자치경찰제에 있어서 주요쟁점의 핵심사항은 자치경찰제를 도입하는 것의 득실관계라고 볼 것인데 이는 관점과 어느 측면에 중점을 둘 것인가에 따라 다르게 나타나게 된다. 지방자치의 존재 이유 중에는 주민 복지적 차원에서 주민의 안전보호가 중요한 부분을 차지하고 있다. 특히 자치경찰제는 수사권독립과 함께 지난 몇 대에 걸친 각 대통령의 선거공약이었기 때문에 노무현 정부 출범 이후 정부는 지방분권차원에서 정부혁신지방분권위원회에서 여러 가지 검토를 해 온 바 있다. 2004년 1월에 정부혁신지방분권위원회의 지방 분권과제 주요과제로 자치경찰제 방안을 검토하기 위해 위원, 관계 공무원 10명으로 자치경찰 T/F를 구성하여 운영한 이 후 자치경찰제 도입방안에 대하여 경찰정과 실시 단위 및 수행 사무 등 주요 쟁점에 대해 협의하면서 실천 가능한 방안을 마련하기 위해서 스페인, 프랑스, 이태리, 그리스 자치경찰기관을 현지 방문하여 외국 자치경찰 제도를 조사한 후 2004년 9월 중순에 자치경찰(안)을 발표하였다. 이 안은 크게 경찰을 사법경찰과 행정경찰로 구분하는 개념 하에 최초로 나온 자치경찰제에 대한 구체적 시행 안이라는 점에서 그 의의를 찾을 수 있을 것이나 지금까지의 기대수준에 과연 부응하는 안이 될 수 있을 것인가에 대한 의문이 제기되고 있다. 동 사안은 2005년 하반기에 시범적으로 시행하고 민선 4기 자치단체장이 출범하는 2006년 하반기에 본격적으로 시행될 것으로 발표하고 발표와 동시에 정부혁신지방분권위원회에서는 본 자치경찰제 기본방향과 법안제정의 원칙과 구체적인 내용에 대한 토론회를 개최하는 등 다양한 홍보를 하였으나 여러 가지 문제점으로 인하여 아직 시행되지 못하고 있다. 따라서 과연 이 안이 한국에서의 자치경찰제 시행에 효과적인 안인가 그렇지 않으면 대선공약을 지키기 위한 일종의 정치적 고려를 한 졸속적인 안이 아닌가에 대한 논란이 제기되고 있다. 지금까지 한국에서는 자치경찰에 대한 많은 토의가 있어 왔으나 이번에 제하고 있고 현재 지방자치단체에서 시행하고 있는 기존 법집행방식과 거의 차이가 없는 상태시된 안은 적어도 지금까지 논의되어왔던 제도와는 매우 생소한 자치경찰 제도를 근간으로 에서 ‘무늬만 자치경찰’ 이라는 비판이 일각에서 제기되고 있는 실정이다. 현재 자치단체에서 시행하고 있는 행정 경찰적 기능을 다소 보완하고 제복착용과 조직을 하나 더 만든 정도가 아닌가 하는 정도이다. 그러므로 본 연구에서는 정부혁신지방분권위원회에서 제시한 자치경찰제도(안)을 중심으로 자치경찰제도 운용의 목적 충족과 실질적인 효과의 측면에서 분석하고 바람직한 자치경찰제도의 운용에 대해 살펴본다.

• Ecology and Resilient Infrastructure
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• v.2 no.4
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• pp.311-316
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• 2015

This study defined and classified no-net-loss-of-greenness (NNLG) based on the law, and then assessed the NNLG index by metropolitan cities and provinces in Korea after estimating NNLG evaluation indicators for the introduction of NNLG for health improvement of urban ecosystems. The results are as follows. First, NNLG was the comprehensive meaning that was included in the greenbelt and park greenbelt and the green area which was defined by the Act on Urban Parks, Greenbelts, etc. and the National Land Planning and Utilization Act respectively. Second, NNLG was classified as a park greenbelt which was included urban parks and greenbelts such as buffer greenbelts, scenic greenbelts, and connecting greenbelts, green areas which was included in green conservation areas, green production areas, green natural areas, and green coverage which is included forests, grasslands, and wetlands that were occupied by vegetation such as trees, shrubs, and plants. Third, NNLG index by cities and provinces was assessed based on the estimation of NNLG evaluation indicators, which included parks and greenbelt areas per capita, green areas per capita, green coverage per capita, ratio of parks and greenbelts, ratio of green areas, and ratio of green coverage. As a result, Sejong city got the highest point of NNLG index and Seoul and Daegu got lowest points of NNLG index among metropolitan cities in Korea. Chungbuk got the highest point of NNLG index and Kyonggi and Jeju got lowest points of NNLG index among provinces in Korea.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.2
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• pp.433-452
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• 2018

The shield tunneling method can minimize surface settlements by preventing the deformation of tunnel face and tunnel intrados due to tunnel excavation. For this purpose, it is very important to control the operating conditions of shield TBM. The face pressure and backfill pressure for tail void grouting should be the most important and immediate measure not only to restrain surface settlement, but also to influence the effective stress and pore water pressure around the circumstance of tunnel during excavation. The reaction of the ground to the application of face pressure and backfill pressure relies on the stiffness and permeability of ground. Especially, the reaction of saturated clayey ground formations, which shows the time-dependent deformation, is different from the permeable ground. Hence, in this paper it was investigated how the TBM operating conditions, ground stiffness, and permeability impact on the surface settlement of saturated clayey ground. For this purpose, a series of parametric studies were carried out by means of the stress-pore water pressure coupled FE analysis. The results show that the settlement of soft clayey ground is divided into the immediate settlement and consolidation settlement. Especially, the consolidation settlement depends on the ground stiffness and permeability. In addition, the existence of critical face pressure and backfill pressure was identified. The face pressure and backfill pressure above the critical value may cause an unexpected increase in the ground settlement.

• Korean Journal of Plant Resources
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• v.33 no.1
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• pp.24-32
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• 2020

This study was aimed to establish the most effective approach for the cultivation of Veronica rotunda var. subintegra (Nakai) T.Yamaz. plants, which was expected as new ornamental plants. We conducted an experiment using plug seedlings, varied the seeding container type and seeding rate. We also varied seedling quality, planting container, soil type, and shading ratio. Seedling quality was used seedlings produced from different seeding containers and seeding rates. The seedling quality were seeding growth using 162, 200, and 288 trays, and seedings rate was used seedlings produced by sowing 1, 2, 4 and 6 seeds. As a result, 162 trays of seedlings were suitable for use in this study. Plants grown with one seed per cell in individual cells exhibited increased individual growth, but those grown with four seeds per cell exhibited better growth for the whole plant. According to seedling quality, seedlings produced in the 162 trays or with four seeds per cell showed higher growth than other seedlings. In the cultivation of V. rotunda var. subintegra (Nakai) T.Yamaz., seedling growth increased depending on container capacity for both shoot and root parts. Container material had no significant impact on seedling growth. Seedlings grew the best on horticultural substrate, and showed better growth on mixed soils with high decomposed granite content than on peatmoss.

• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.35-45
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• 2014

Limit equilibrium methods of slope stability analysis have been widely adopted mainly due to their simplicity and applicability. However, the conventional methods may not give reliable and convincing results for various geological conditions such as nonhomogeneous and anisotropic soils. Also, they do not take into account soil slope history nor the initial state of stress, for example excavation or fill placement. In contrast to the limit equilibrium analysis, the analysis of deformation and stress distribution by finite element method can deal with the complex loading sequence and the growth of inelastic zone with time. This paper proposes a technique to determine the critical slip surface as well as to calculate the factor of safety for shallow failure on partially saturated soil slope. Based on the effective stress field in finite element analysis, all stresses are estimated at each Gaussian point of elements. The search strategy for a noncircular critical slip surface along weak points is appropriate for rainfall-induced shallow slope failure. The change of unit weight by seepage force has an effect on the horizontal and vertical displacements on the soil slope. The Drucker-Prager failure criterion was adopted for stress-strain relation to calculate coupling hydraulic and mechanical behavior of the partially saturated soil slope.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.236-244
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• 2005

In this study, we introduce a new topology of Fuzzy Polynomial Neural Networks(FPNN) that is based on fuzzy relation and evolutionally optimized Multi-Layer Perceptron, discuss a comprehensive design methodology and carry out a series of numeric experiments. The construction of the evolutionally optimized FPNN(EFPNN) exploits fundamental technologies of Computational Intelligence. The architecture of the resulting EFPNN results from a synergistic usage of the genetic optimization-driven hybrid system generated by combining rule-based Fuzzy Neural Networks(FNN) with polynomial neural networks(PNN). FNN contributes to the formation of the premise part of the overall rule-based structure of the EFPNN. The consequence part of the EFPNN is designed using PNN. As the consequence part of the EFPNN, the development of the genetically optimized PNN(gPNN) dwells on two general optimization mechanism: the structural optimization is realized via GAs whereas in case of the parametric optimization we proceed with a standard least square method-based learning. To evaluate the performance of the EFPNN, the models are experimented with the use of several representative numerical examples. A comparative analysis shows that the proposed EFPNN are models with higher accuracy as well as more superb predictive capability than other intelligent models presented previously.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.169-179
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• 2003

Undrained shear strength of clay deposit is one of the most important properties in the design of geotechnical structures. The use of piezocone test is rapidly growing due to its merit that can measure the in-situ undrained shear strength continuously with less error. The reliability of the shear strength from piezocone test depends upon the cone factor applied. Many researchers have suggested different ranges of values for the factors. This study performs to find out the validity of the suggested values in Korea and their charateristics related to the mechanical properties of clay. Piezocone tests were performed at the site of pilot project of ground improvement at Yangsan-Mulgeum Gyeongnam to investigate the charateristics of piezocone factors. The piezocone fators$(N_{kt}, N_{ke}, N_{\Delta u})$ based on the undrained shear strength from quick triaxial compression test are generally within the suggested range. And there appears considerable relations between undrained shear strength and $(N_{kt}, N_{ke}, N_{\Delta u})$ and between preconsolidation pressure and $(N_{kt}, N_{ke})$, while plasticity index, rigidity index and friction ratio do not show any relations with cone factors. The results also reveal that factor $(N_{\Delta u})$ shows higher reliability than factors $(N_{kt} and N_{ke})$, which show smaller standard deviation, breadth of change and scattering.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.261-271
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• 2003

A condition evaluation procedure for the pavement foundations using multi-load level Falling Weight Deflectometer(FWD) deflections is presented in this paper. A dynamic finite element program incorporating a stress-dependent material model, was used to generate the synthetic deflection database. Based on this synthetic database, the relationships between surface deflections and critical responses, such as stresses and strains in base and subgrade layers, have been established. FWD deflection data, Dynamic Cone Penetrometer(UP) data, and repeated load resilient modulus testing results used in developing this procedure were collected from the Long Term Pavement Performance (LTPP) and North Carolina Department of Transportation (NCDOT) database. Research effort focused on investigation of the effect of the FWD load level on the condition evaluation procedures. The results indicate that the proposed procedure can estimate the pavement foundation conditions. It is also found that structurally adjusted Base Damage Index (BDI) and Base Curvature Index (BCI) are good indicators for the prediction of stiffness characteristics of aggregate base and subgrade respectively. A FWD test with a load of 66.7 kN or less does not improve the accuracy of this procedure. Results from the study for the nonlinear behavior of a pavement foundations indicate that the deflection ratio obtained from multi-load level deflections can predict the type and quality of the pavement foundation materials.