• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.466-475
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• 2006

Reliability analysis between safety factor and reliability index for driven and bored pile load capacity was analyzed in this study. 0.1B, Chin, De Beer, and Davisson's methods were used for determining pile load capacity by using load-settlement curve from pile load test. Each method define ultimate, yield and allowable pile load capacities. LCPC method using CPT results was performed for comparing with results of pile load test. Based on FOSM analysis using load factors, it is obtained that reliability indices for ultimate pile load capacity were higher than those of yield and allowable condition. Present safety factor 2 for yield and allowable load capacities are not enough to satisfy target reliability index $2.0\sim2.5$. However, it is sufficient for ultimate pile load capacity using safety factor 3.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.126-129
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• 1999

In this paper, it is assumed that a mobile radio channel is a Rayleigh distributed multipath fading channel and Erlang capacity and equivalent channel numbers are calculated for the reverse link of a imperfect power controlled DS/CDMA cellular system considering both shadowing and multipath fading. The DS/CDMA blocking probability is calculated based on a new analysis method that considers Erlang capacity and ICF(interference correction factor) using the median value of $E_{b(i)}$/ $I_{o}$ corresponding to each reverse link user. It is showed that the effect of multipath fading must not be ignored in Erlang capacity of the IS-95 DS/CDMA cellular system and the Erlang capacity is decreased according to the increase of the deviation of the imperfect power control, to the decrease of the processing gain, to the increase of the voice activity.y.

• 한국해양공학회지
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• 제10권4호
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• pp.141-148
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• 1996

Use of stone column for deep ground treatment in soft clay soils is an effective method. The stone column significantly increases load carrying capacity of the soft clay soil. A analysis method for bearing capacity of stone column in soft clay soil is developed. The capacity made by developed method are compared wity observed values from field load test and a reasonable correlation is noted.

• 한국통신학회논문지
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• 제25권10B호
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• pp.1641-1647
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• 2000

This paper presents an analysis of coverage and capacity for the multi-layer CDMA cellular system. The multi-layer CDMA system that shares a common frequency band consists of macrocells for outdoor users and picocells for indoor users. Though macrocells and picocells interfere with each other the capacity of the whole system can be increased, We have analyzed the effect of muual interference upon cell coverage soft handover areas and capacities. The parameters involved in the engineering of the system are discussed. The study results sow that we can control the service coverage of indoor picocells with the system parameters set properly. It is also show that the capacity of the whole system that the capacity of the whole system can be enhanced smoothly by deploying the indoor picocells within existing macrocells.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.157-164
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• 2002

Based on the results of prototype air-shaft construction, penetration capacity of RBM(Raise Boring Machine) was analyzed and compared with TBM(Tunnel Boring Machine) performance in this study. Utilization, down time, net penetration rate and advance rate were evaluated and compared. By conducting the laboratory tests for rock properties with the analysis of penetration capacity, relation of penetration capacity and geotechnical parameters was studied. The results showed that much more higher value of utilization, however lower value of net penetration rate for RBM was obtained compared to those of TBM. In addition, as the strength of rock penetrated increased, higher value of net penetration rate was obtained contrarily to the results of TBM performance. Finally, new relationship between total hardness and net penetration rate for weak and weathered rock was derived from these results.

• 한국자동차공학회논문집
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• 제6권6호
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• pp.174-184
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• 1998

The situation frequently occurs in which the input torque capacity of the torque converter should be changed. It is known that the modification of the outlet blade angles of the torque converter elements is suitable for such situation with the outer diameter of flow path of the converter maintained. But so far it has been difficult to predict correctly the converter characteristics as well as the effect of outlet angles on torque capacity in the past numerical methods. In the present numerical method introducing the interrow mixing planes, the torque capacity was satisfactorily estimated and it was shown that the torque capacity could be effectively changed by modifying the outlet blade angles of pump and stator.

• 한국폐기물자원순환학회지
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• 제34권5호
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• pp.468-473
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• 2017

This study was carried out to examine the characteristics of hydrogen sulfide adsorption using an iron hydroxide-based adsorbent. The prepared adsorbent was discussed with regard to its adsorption capacity and analyzed via surface analysis methods to illustrate the physical characteristics of hydrogen sulfide adsorption. As the drying temperature increased, the adsorption capacity of the adsorbent decreased from 29.15wt% to 22.73wt%. The adsorption capacity was decreased as the space velocity increased and showed an adsorption capacity of about 3.65 at $3,157.6h^{-1}$. The effect of sulfur dioxide was to decrease the adsorption capacity from 29.15wt% to 27.94wt%. The adsorbent exhibited the amorphous type in its physical appearance based on XRD and EDS analysis.

• Geomechanics and Engineering
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• 제35권2호
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• pp.165-179
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• 2023

This study investigates the uplift capacity of a single vertical belled pile buried at shallow depth in dry sand. The laboratory model experiments are conducted with different pile-tip angles and relative densities. In addition, image and FEM analyses are performed to observe the failure surface of the belled pile for different pile-tip angles and relative densities. Accordingly, the uplift capacity and failure angle in the failure surface of the belled pile were found to depend on the belled pile-tip angle and relative density. A predictive model for the uplift capacity of the belled pile was proposed considering the relative density and belled pile-tip angle based on a previous limit equilibrium equation. To validate the applicability of the proposed model, the values calculated using the proposed and previous models were compared to those obtained through a laboratory model experiment. The proposed model had the best agreement with the laboratory model experiment.

• Structural Engineering and Mechanics
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• 제72권1호
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• pp.43-60
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• 2019

This paper presents a finite element model which can simulate the axial compression behavior of steel reinforced recycled concrete (SRRC) filled square steel tube columns using the ABAQUS software. The analytical model was established by selecting the reasonable nonlinear analysis theory and the constitutive relationship of material in the columns. The nonlinear analysis of failure modes, deformation characteristics, stress nephogram, and load-strain curves of columns under axial loads was performed in detail. Meanwhile, the influences of recycled coarse aggregate (RCA) replacement percentage, profile steel ratio, width thickness ratio of square steel tube, RAC strength and slenderness ratio on the axial compression behavior of columns were also analyzed carefully. It shows that the results of finite element analysis are in good agreement with the experimental results, which verifies the validity of the analytical model. The axial bearing capacity of columns decreased with the increase of RCA replacement percentage. While the increase of wall thickness of square steel tube, profile steel ratio and RAC strength were all beneficial to improve the bearing capacity of columns. Additionally, the parameter analysis of finite element analysis on the columns was also carried out by using the above numerical model. In general, the SRRC filled square steel tube columns have high bearing capacity and good deformation ability. On the basis of the above analysis, a modified formula based on the American ANSI/AISC 360-10 was proposed to calculate the nominal axial bearing capacity of the columns under axial loads. The research conclusions can provide some references for the engineering application of this kind of columns.

• 대한토목학회논문집
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• 제29권1D호
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• pp.41-48
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• 2009

신호교차로 용량분석 방법은 국내외에서 주로 사용하고 있는 HCM 방법과 본 연구에서 제시하고자하는 ICU 방법이 있다. HCM 방법은 교통량, 신호운영, 기하구조 자료에 의해 교차로의 지체를 산정하는 운영 분석에 초점이 맞춰져 있고, 계획 및 설계 분석은 반복적인 운영분석을 통해 이루어져 복잡하다. 반면 ICU 방법은 기하구조 및 교통량 자료만으로 교차로 계획 및 설계 분석이 가능하고 용이하며 최소녹색시간을 고려하는 장점이 있다. 본 연구에서는 ICU 방법에 대해 살펴보고, 교통량 시나리오를 구성하여 HCM 방법과 ICU 방법을 비교 분석하였다. 또한 중요교차로 설정을 위한 도시간선도로 축 상의 교차로 용량분석, 횡단보도 유형, 차로수, 차로이용, 좌회전 운영방식 변경의 효과분석에 ICU를 적용 분석함으로써 계획 및 설계 분석 시 ICU 적용의 효율성을 살펴보았다. 분석결과 ICU 방법이 최소녹색시간의 영향을 반영하여 광로로 이루어진 도시 교차로의 정확한 용량상태를 파악할 수 있고, 신호시간 등의 상세한 자료 없이 간편하게 적용할 수 있어 계획 및 설계 분석에 효율적인 것으로 나타났다. 본 연구결과를 토대로 기하구조나 운영방식 변경 등의 계획 분석에 ICU 방법을 유용하게 적용하여 계획 교차로의 정확한 용량상태를 파악함으로써 적절한 계획 및 개선이 이루어질 수 있을 것으로 기대된다.