• Title/Summary/Keyword: depth determination

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Influence of Loss Function on Determination of Optimal Thickness of Consolidating Layer for Songdo New City (손실함수가 송도신도시의 최적 압밀층 두께 결정에 미치는 영향)

  • Kim, Dong-Hee;Ryu, Dong-Woo;Chae, Young-Ho;Park, Jung-Kyu;Lee, Woo-Jin
    • Journal of the Korean Geotechnical Society
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    • v.27 no.8
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    • pp.51-61
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    • 2011
  • Spatial estimation of the thickness and depth of the geological profile has been regarded as an important procedure for the design of soft ground. A minimum variance criterion, which has often been used in traditional kriging techniques, does not always guarantee the optima1 estimates for the decision-making process in geotechnical engineering. In this study, a geostatistica; framework is used to determine the optimal thickness of the consolidation layer and the optimal area that needs the adoption of prefabricated vertical drains via indicator kriging and loss function. From the exemplary problem, different optimal estimates can be obtained depending on the loss function chosen. The design procedure and method considering the minimum expected loss presented in this paper can be used in the decision-making process for geotechnical engineering design.

Chloride Ion Penetration Properties of Normal Strength High-Fluidity Concrete Using Lime Stone Powder (석회석 미분말을 활용한 보통강도 고유동 콘크리트의 염소이온 침투특성)

  • Choi, Yun-Wang;Moon, Jae-Heum;Eom, Joo-Han
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.14 no.4
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    • pp.160-168
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    • 2010
  • Recently, there are a lot of researches related to the high-fluidity concrete (HFC) with field applications. However, most applications and studies are with concretes with high strength level so there are little studies about durability evaluations such as chloride ion penetration properties with normal strength concrete. Therefore, to evaluate the durability of HFC with normal strength level, this study performed the chloride ion penetration test and observed the micro pore distribution with normal strength HFC which contains limestone powder. Experimental results showed that most micro-pores have diameters between 0.005 to 0.05 ${\mu}m$ with HFCs using limestone powder and the average diameter becomes larger with the increase of limestone powder content. Also, it was shown that, with the increase of the limestone powder content, penetration depth and diffusion coefficient of chloride ion increased and diffusion coefficient had good relationships with compressive strength and average pore diameter with the coefficient of determination over 0.90.

Determination of Cadmium and Zinc Contamination Source in Arable Soil in the Vicinity of a Zinc Smelting Factory

  • Hong, Chang-Oh;Gutierrez, Jessie;Lee, Seul-Bi;Lee, Yong-Bok;Yu, Chan;Kim, Pil-Joo
    • Korean Journal of Environmental Agriculture
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    • v.26 no.3
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    • pp.204-209
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    • 2007
  • Agricultural area in the vicinity of the ${\triangle}{\triangle}$ smelting factory in Kyeongbuk province, the third largest zinc smelting factory in the world, was contaminated by high concentration of heavy metals. However, the heavy metals source was not yet directly traced and thus, resulted to a conflict between the factory and residents within its vicinity. In order to determine the level of heavy metal contamination in the arable lands located at the north eastern part of the factory, soils were sampled systematically. To find out the major reason for the occurrence of this problem, waters and aerosols were sampled with constant intervals to the upward and downward direction from the factory and were analyzed to find out the heavy metal concentrations. Cadmium (Cd) and zinc (Zn) of the heavy metals were highly accumulated more than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with mean values 1.7 and 407 mg $kg^{-1}$, respectively, at the surface soils (0-20 cm), and heavy metal concentration significantly decreased with increasing soil depth In addition, the concentration of both metals slightly decreased with increasing distance from the factory to the surface soils. Cadmium and Zn were detected in the upward stream water with low concentration and concentrations increased significantly in the downstream after passing across the factory. Aerosol samples also showed traces of Cd and Zn which could be attributed to the contamination of the water system and the surface soils. Conclusively, Cd and Zn emitted from the ${\triangle}{\triangle}$ smelting factory moved with the aerosol in the atmosphere and thus, contaminated the agricultural areas and the water system within it vicinity.

Determination of $CO_2$ Laser Output Power for the Skin Incision in Beagle Dogs (비글견의 피부절개를 위한 $CO_2$ 레이저의 출력 결정)

  • Shin, Beom-Jun;Jeong, Hyun-Woong;Son, Hwa-Young;Jung, Ju-Young;Park, Seong-Jun;Kim, Myung-Cheol;Jeong, Seong-Mok
    • Journal of Veterinary Clinics
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    • v.25 no.5
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    • pp.379-384
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    • 2008
  • The objective of this study was to determine output power for skin incision in 0.3 mm spot diameter $CO_2$ laser by measuring (1) the wound depth, (2) initial dermal tissue damage, (3) degree of wound healing at different power (4W, 5W and 6W) in beagle dogs. Three healthy 2-year-old beagle dogs were used. Four 2 cm straight skin incisions were made with 0.3 mm spot diameter $CO_2$ laser on the each dog's both side of dorsal midline in three beagle dogs. The skin incisions were performed for $10{\sim}15$ seconds for same dosage. And then each wound was closed with surgical stapler. At 0, 3, 7 and 14 days after initial wounding, each wound was taken for histological observation. On macroscopic and microscopic observation, initial incisional wound did not show difference in three group. And also re-epithelialization, dermal tissue damage and inflammatory response did not show significant difference among groups. This study reveals that 4W, 5W and 6W may be suitable output power in 0.3 mm spot diameter $CO_2$ laser for the skin incision in beagle dogs.

Criteria for calculation of CSO volume and frequency using rainfall-runoff model (우수유출 모형을 이용한 합류식하수관로시스템의 월류량, 월류빈도 산정 기준 결정 연구)

  • Lee, Gunyoung;Na, Yongun;Ryu, Jaena;Oh, Jeill
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.3
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    • pp.313-324
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    • 2013
  • It is widely known that untreated Combined Sewer Overflows (CSOs) that directly discharged from receiving water have a negative impact. Recent concerns on the CSO problem have produced several large scale constructions of treatment facilities, but the facilities are normally designed under empirical design criteria. In this study, several criteria for defining CSOs (e.g. determination of effective rainfall, sampling time, minimum duration of data used for rainfall-runoff simulation and so on) were investigated. Then this study suggested a standard methodology for the CSO calculation and support formalized standard on the design criteria for CSO facilities. Criteria decided for an effective rainfall was over 0.5 mm of total rainfall depth and at least 4 hours should be exist between two different events. An Antecedent dry weather period prior to storm event to satisfy the effective rainfall criteria was over 3 days. Sampling time for the rainfall-runoff model simulation was suggested as 1 hour. A duration of long-term simulation CSO overflow and frequency calculation should be at least recent 10 year data. A Management plan for the CSOs should be established under a phase-in of the plan. That should reflect site-specific conditions of different catchments, and formalized criteria for defining CSOs should be used to examine the management plans.

Determination of Factors in Cultural Dimensions and SERVQUAL Model Affecting the Corporate Image of Pharmacy Retail Stores

  • KLONGTHONG, Worasak;THAVORN, Jakkrit;WATCHARADAMRONGKUN, Suntaree;NGAMKROECKJOTI, Chittipa
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.10
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    • pp.875-884
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    • 2020
  • Thailand has a rapidly growing pharmaceutical sector, which is the eighth largest in the Asia-Pacific region and one of the largest and most developed among the Association of Southeast Asian Nations (ASEAN) countries. This study examines how to provide the most appropriate approach to enhance Thailand's pharmaceutical services to dispense medicine to end consumers. The main objective is to determine the most appropriate corporate image for Thai Pharmacy Retail Stores (PRSs) for entering the ASEAN market community. An exploratory mixed-method design characterized by qualitative and quantitative phases of data collection and analysis and the linking of data from these two separate data strands was adopted to conduct an in-depth interview with pharmacists and the owner of pharmacy retail stores as well as 405 respondents who had visited a pharmacy retail store and interacted with pharmacists during the previous year. The multiple linear regression (MLR) was applied to analyze the relative influences of perceived service quality and the cultural dimension on the corporate image. Findings reveal that the perceived service quality and cultural dimension contribute 50% towards the corporate image, and the perceived service quality had more effect than cultural dimension. This study mainly focuses on PRSs in Thailand, while the findings show other analyses concerning how to successfully create and promote an effective PRS image for ASEAN markets.

Assessment on Carbonation Resistance of Products for Protection and Repair of Concrete Structures (콘크리트 구조물 보수용 단면복구재 및 표면보호재의 중성화 저항성 평가)

  • Park, Sang-Soon;Ryu, Chung-Hyun;Park, Hun-Il;Shin, Hong-Chul;Ryu, Byung-Cheol;Kim, Young-Geun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.625-628
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    • 2008
  • This study is performed to evaluate the carbonation resistance by measuring carbonation penetration depth and diffusion equivalent air layer thickness for 3 types of repair materials and 2 types of surface protection materials. Diffusion equivalent air layer thickness($S_D$) is thickness of a static air layer that possesses, under the same conditions, the same carbon dioxide permeability as the coating in accordance BS EN 1062-6. There is a significant advantage that continuous test is possible because it does not destroy the specimen. From experiment results, it is concluded that determination of carbon dioxide permeability is effective to evaluate for surface coating materials.

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Strut-tie model for two-span continuous RC deep beams

  • Chae, H.S.;Yun, Y.M.
    • Computers and Concrete
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    • v.16 no.3
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    • pp.357-380
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    • 2015
  • In this study, a simple indeterminate strut-tie model which reflects complicated characteristics of the ultimate structural behavior of continuous reinforced concrete deep beams was proposed. In addition, the load distribution ratio, defined as the fraction of applied load transferred by a vertical tie of truss load transfer mechanism, was proposed to help structural designers perform the analysis and design of continuous reinforced concrete deep beams by using the strut-tie model approaches of current design codes. In the determination of the load distribution ratio, a concept of balanced shear reinforcement ratio requiring a simultaneous failure of inclined concrete strut and vertical steel tie was introduced to ensure the ductile shear failure of reinforced concrete deep beams, and the primary design variables including the shear span-to-effective depth ratio, flexural reinforcement ratio, and compressive strength of concrete were reflected upon. To verify the appropriateness of the present study, the ultimate strength of 58 continuous reinforced concrete deep beams tested to shear failure was evaluated by the ACI 318M-11's strut-tie model approach associated with the presented indeterminate strut-tie model and load distribution ratio. The ultimate strength of the continuous deep beams was also estimated by the experimental shear equations, conventional design codes that were based on experimental and theoretical shear strength models, and current strut-tie model design codes. The validity of the proposed strut-tie model and load distribution ratio was examined through the comparison of the strength analysis results classified according to the primary design variables. The present study associated with the indeterminate strut-tie model and load distribution ratio evaluated the ultimate strength of the continuous deep beams fairly well compared with those by other approaches. In addition, the present approach reflected the effects of the primary design variables on the ultimate strength of the continuous deep beams consistently and reasonably. The present study may provide an opportunity to help structural designers conduct the rational and practical strut-tie model design of continuous deep beams.

Applicability of Geophyscal Well Logging in the Assessment of Seawater Intrusion (임해지역 해수침투 평가를 위한 물리검층의 적용성)

  • Lee Sang-Gyu;Hwang Sae-Ho;Hwang Hak-Su;Park In-Hwa
    • Geophysics and Geophysical Exploration
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    • v.3 no.3
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    • pp.101-111
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    • 2000
  • In order to assess the seawater intrusion, induction, temperature and conductivity of fluid, and natural gamma logs were obtained in nine wells at the three study areas having different hydrogeologic characteristics. Besides surface geophysical exploration, supplementary geophysical well logs were carried out to understand the hydrogeological characteristics related to the seawater intrusion in the study areas. The geophysical well logs have been proved to increase the accuracy of interpretation of the surface geophyscial exploration's data for assessment of seawater intrusion, and to get the optimum depth for a long monitoring of groundwater. They, also, revealed that the identification of hydrogeological units for strata's porosity was able to be achieved and were illustrated the applicability of geophysical well logs monitoring. Finally, geophysical well logs are expected to play to get the more quantitative information of seawater infusion, if it is fully collaborated with a better method that is strata's resistivity determination with not relatively much effected by seawater within the drilled borehole and that is the porosity measurement with built on small diameter PVC casing.

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A Study on the Optimum Mix Proportion of the Mass Concrete Designed as Massive and Deep Structure

  • Kwon Yeong-Ho;Lee Hwa-Jin
    • Journal of the Korea Concrete Institute
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    • v.17 no.2 s.86
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    • pp.293-302
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    • 2005
  • This study describes data from determination of the optimum mix proportion and site application of the mass concrete placed in bottom slab and side wall having a large depth and section as main structures of LNG in-ground tank. This concrete requires low heat hydration, excellent balance between workability and consistency because concreting work of LNG in-ground tank is usually classified by under-pumping, adaptation of longer vertical and horizontal pumping line than ordinary pumping condition. For this purpose, low heat Portland cement and lime stone powder as cementitious materials are selected and design factors including unit cement and water content, water-binder ratio, fine aggregate ratio and adiabatic temperature rising are tested in the laboratory and batch plant. As experimental results, the optimum unit cement and water content are selected under $270kg/m^3$ and $l55{\~}l60 kg/m^3$ separately to control adiabatic temperature rising below $30^{\circ}C$ and to improve properties of the fresh and hardened concrete. Also, considering test results of the confined water ratio($\beta$p) and deformable coefficient(Ep), $30\%$ of lime stone powder by cement weight is selected as the optimum replacement ratio. After mix proportions of 5cases are tested and compared the adiabatic temperature rising($Q^{\infty}$, r), tensile and compressive strength, modulus of elasticity, teases satisfied with the required performances are chosen as the optimum mix design proportions of the side wall and bottom slab concrete. $Q^{\infty}$ and r are proved smaller than those of another project. Before application in the site, properties of the fresh concrete and actual mixing time by its ampere load are checked in the batch plant. Based on the results of this study, the optimum mix proportions of the massive concrete are applied successfully to the bottom slab and side wall in LNG in-ground tank.