• Geomechanics and Engineering
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• 제35권1호
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• pp.1-11
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• 2023

A growing trend of utilizing helical piles for soft soil strata to support infrastructure projects is currently observed in Saemangeum, South Korea. Recognized mainly due to its ease of installation and reusability proves to be far more superior compared to other foundation types in terms of sustainability. This study applies modified p-y springs to characterize the behavior of a laterally loaded helical pile with a shaft diameter of 89.1 mm affixed with 3 helices evenly spaced along its embedded length of 2.5 m. Geotechnical soil properties are correlated from CPT data near the test bed vicinity and strain gauges mounted on the shaft surface. A modification factor is applied on the p-y springs to adjust the simulated data and match it to the bending moment, soil resistance and deflection values from the strain gauge measurements. The predicted lateral behavior of the helical pile through the numerical analysis method shows fairly good agreement to the recorded field test results.

• 셀메드
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• 제8권3호
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• pp.11.1-11.6
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• 2018

In vitro anti-obesity effects of anti-cancer (AC) functional kimchi in differentiated 3T3-L1 adipocytes were studied. We constructed three experimental groups: Control, standardized kimchi (SK), and AC functional kimchi (A-FK) that included active ingredients and Lactobacillus plantarum. Kimchi extracts did not show any cytotoxicity in pre-adipocytes in the concentration range of 1 - 5 mg/mL. A-FK significantly reduced fat droplet formation and absorbance in differentiated 3T3-L1 adipocytes, as shown by Oil red O staining, compared to Control and SK (P < 0.05). SK and A-FK reduced adipo-/lipogenesis related genes such as $C/EBP{\alpha}$, SREBP-1, LPL, and $LXR{\alpha}$ compared to Control (P < 0.05). Especially, A-FK more greatly reduced SREBP-1 and LPL compared to SK (P < 0.05). A-FK up-regulated the ${\beta}$-oxidation related gene CPT-1c and down-regulated the pro-inflammatory cytokine IL-6 compared to Control (P < 0.05). Based on the results, A-FK exhibited anti-obesity effects by inhibiting fat droplet formation and adipo-/lipogenesis related genes by regulating the ${\beta}$-oxidation related gene CPT-1c and pro-inflammatory cytokine IL-6. In previous studies, A-FK kimchi already exhibited a strong anti-cancer effect. These results indicate that A-FK increased anti-obesity activity in this model system due to its functional ingredients and anti-cancer functionality.

• 한국지반공학회논문집
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• 제22권11호
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• pp.65-73
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• 2006

최근 신뢰성 이론에 바탕을 둔 한계상태설계법(Limit State Design)이 국제적으로 도입되고있는 추세이다. 이에 본 연구에서는 사질토 지반에 근입된 항타 및 현장타설 말뚝의 지지력 산정법에 대한 신뢰도지수와 안전율과의 관계를 규명하고자 하였다. 본 연구는 말뚝 직경의 10% 침하 시 지지력을 결정하는 방법(0.1B), Chin의 방법, De Beer의 방법과 Davisson의 방법에 대한 말뚝 지지력 산정결과를 비교 분석하였고, 말뚝의 지지력 산정 시 유용하게 활용되는 CPT결과를 통한 말뚝의 지지력 산정법 중에서 LCPC법에 의한 지지력과의 비교를 통해 FOSM법을 바탕으로 각 산정 법에 대한 신뢰도를 평가하였다 각 말뚝지지력 해석 방법에 따른 안전율과 신뢰도지수 관계 분석결과, 극한지지력을 규정하는 0.1B와 Chin의 방법에 대한 신뢰도지수가 De Beer와 Davisson에 의한 신뢰도지수보다 높은 것으로 나타났으며, 목표신뢰도지수 $2.0{\sim}2.5$를 기준으로 하여 항타 말뚝에서의 안전율 2는 방법에 따라 다소 증대될 필요가 있고, 현장 타설 말뚝에서는 극한 지지력 확인시 안전율 3보다 작게 적용할 수 있는 여지가 있음을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권3호
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• pp.390-397
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• 2020

Objective: The objective of this study was to measure the special expression pattern of lipid metabolism genes and investigate the molecular mechanisms underlying intramuscular fat (IMF) deposition in Longissimus dorsi muscle of Laiwu pigs. Methods: Thirty-six pigs (Laiwu n = 18; Duroc×Landrace×Yorkshire n = 18) were used for the measurement of the backfat thickness, marbling score, IMF content, and expression of lipid metabolism genes. Results: Significant correlations were found between IMF content and the mRNA expression of lipid metabolism genes. Of the 14 fat deposition genes measured, fatty acid synthase (FASN) showed the strongest correlation (r = 0.75, p = 0.001) with IMF content, and of the 6 fat removal genes, carnitine palmitoyl transferase 1B (CPT1B) exhibited the greatest negative correlation (r = -0.66, p = 0.003) with IMF content in Laiwu pig. Multiple regression analysis showed that CPT1B, FASN, solute carrier family 27 member 1 (SLC27A1), and fatty acid binding protein 3 (FABP3) contributed 38% of the prediction value for IMF content in Laiwu pigs. Of these four variables, CPT1B had the greatest contribution to IMF content (14%) followed by FASN (11%), SLC27A1 (9%), and FABP3 (4%). Conclusion: Our results indicate that the combined effects of an upregulation in fat deposition genes and downregulation in fat removal genes promotes IMF deposition in Laiwu pigs.

• 한국전문물리치료학회지
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• 제10권2호
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• pp.11-22
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• 2003

The purpose of this study was to analyze the effects of three different pelvic tilts on a sit-to-stand (STS) and to suggest a new assessment approach based on biomechanical analysis. The three difrent pelvic tilts were: (1) comfortable pelvic tilt sit-to-stand (CPT STS), (2) posterior pelvic tilt sit-to-stand (PPT STS) and (3) anterior pelvic tilt sit-to-stand (APT STS). To determine the onset time of muscle contraction surface electrodes were applied to the rectus femoris muscle (RF), vastus lateralis muscle (VL), biceps femoris muscle (BF), tibialis anterior muscle (TA), gastrocnemius muscle (GCM), and soleus muscle (SOL). The ICC was used for functional linkage analysis. The findings of this study were as follows. First, significant differences were found in kinematic variables and in muscle activation pattern among the three activities. Second, the results of functional integrated analysis revealed that recruited muscle activation patterns changed when the thigh-off was viewed as a reference point. Third, there were independent functional units between the thigh-off and the VL and between the thigh-off and the RF in the functional linkage analysis. The VL and RF acted as prime mover muscles, and more postural adjustment muscle recruitment was required as the demand of postural muscle control increased (PPT STS, APT STS, and CPT STS in order). In conclusion, the findings of this study suggest the following evaluative and therapeutic approach for STS activity. APT STS can be introduced for movement efficiency and functional advantage when abnormal STS is treated. However, excessive APT would change the muscle activation patterns of BF and SOL and require additional postural muscle control to cause abnormal control patterns.

• Asian Pacific Journal of Cancer Prevention
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• 제17권11호
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• pp.4853-4856
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• 2016

Objective: Gimatecan is a new camptothecin (CPT) analogue that inhibits tumor growth by targeting DNA topoisomerase I (TOP I) and introducing strong and persistent DNA cleavage. Anti-tumor activity has been demonstrated with a wide range of solid tumors in previous preclinical and clinical studies. Here, we investigated for the first time the effects of gimatecan on the proliferation of hepatocellular carcinoma (HCC) cells both in vitro and in vivo. Methods: Anticancer efficacy of gimatecan were evaluated in a panel of HCC cell lines and corresponding mouse xenograft models. Inhibition of cell proliferation was measured by CellTiter-Glo cell viability assay. In vivo, gimatecan and control preparations were orally administered every four days, for a total of four times. Tumor volume and body weights of the mice were measured twice weekly. Results: In vitro cytotoxicity evaluation showed that gimatecan inhibited the proliferation of a large panel of HCC cell lines in a dose dependent manner, with IC50 values ranging between 12.1~1085.0 nM. In vivo evaluation in mouse xenograft models showed significant antitumor effects of gimatecan at 0.8mg/kg and 0.4mg/kg as compared to the control group. Conclusion: This study suggested that gimatecan may have the potential to be used as a chemotherapeutic agent for the treatment of HCC.

• Geomechanics and Engineering
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• 제11권5호
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• pp.671-690
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• 2016

This work presents a static flexure analysis of laminated composite plates by utilizing a higher order shear deformation theory in which the stretching effect is incorporated. The axial displacement field utilizes sinusoidal function in terms of thickness coordinate to consider the transverse shear deformation influence. The cosine function in thickness coordinate is employed in transverse displacement to introduce the influence of transverse normal strain. The highlight of the present method is that, in addition to incorporating the thickness stretching effect (${\varepsilon}_z{\neq}0$), the displacement field is constructed with only 5 unknowns, as against 6 or more in other higher order shear and normal deformation theory. Governing equations of the present theory are determined by employing the principle of virtual work. The closed-form solutions of simply supported cross-ply and angle-ply laminated composite plates have been obtained using Navier solution. The numerical results of present method are compared with those of the classical plate theory (CPT), first order shear deformation theory (FSDT), higher order shear deformation theory (HSDT) of Reddy, higher order shear and normal deformation theory (HSNDT) and exact three dimensional elasticity theory wherever applicable. The results predicted by present theory are in good agreement with those of higher order shear deformation theory and the elasticity theory. It can be concluded that the proposed method is accurate and simple in solving the static bending response of laminated composite plates.

• Coupled systems mechanics
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• 제11권4호
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• pp.357-371
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• 2022

This paper presents a parametric study on the free vibration analysis of a functionally graded material (FGM) circular plate with non-uniform thickness resting on a variable Pasternak elastic foundation. The mechanical properties of the material vary in the transverse direction through the thickness of the plate according to the power-law distribution to represent the constituent components. The equation of motion of the circular plate has been carried out based on the classical plate theory (CPT), and the differential quadrature method (DQM) is employed to solve the governing equations as a semi-analytical method. The grid points are chosen based on Chebyshev-Gauss-Lobatto distribution to achieve acceptable convergence and better accuracy. The influence of geometric parameters, variable elastic foundation, and functionally graded variation for clamped and simply supported boundary conditions on the first three natural frequencies are investigated. Comparisons of results with similar studies in the literature have been presented and two-dimensional mode shapes for particular plates have been plotted to illustrate the effect of variable thickness profile.

• 한국지반공학회논문집
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• 제28권11호
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• pp.41-52
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• 2012

석션드레인공법은 연직배수재를 통해 연약지반에 직접 진공압을 가하게 되므로 진공압에 의해 배수재 주변의 경화영역이 형성된다. 이러한 경화영역은 지반의 투수성을 저하시켜 간극수 배출 효율이 급격히 저하된다. 본 연구에서는 배수효율을 저하시키는 요인 중 하나인 경화영역을 최소화하기 위해 단계 진공압을 고려하였다. 단계 진공압(-20kPa, -40kPa, -60kPa, -80kPa) 적용 기간이 경화영역과 지반개량 효과에 미치는 영향을 평가하기 위해 부산 해성 점토를 대상으로 단계별로 진공압 적용일자를 달리하여 실내시험을 수행하였다. 강도(CPT) 및 함수비 시험과 이론적 검증을 통해 경화영역의 범위는 약 7.0cm 이내이고, 경화영역 내에서의 투수계수 저하비는 약 2.0~4.0으로 평가되었다. 또한, 일괄적인 진공재하방식보다는 단계재하방식이 최종침하량 측면에서 더 우수한 것으로 나타났으며, 단계별 진공압의 적용기간도 대상 점토의 특성을 고려하여 결정되어야 함을 보였다. 수치해석 결과 경화영역을 고려하는 것이 실측값에 유사한 결과를 도출할 수 있음을 확인하였다.

• 한국지반공학회논문집
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• 제25권11호
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• pp.105-115
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• 2009

본 연구에서는 제주특별자치도 강정항 인근 해역에서 채취한 해사의 기본특성을 분석하고, 실내 챔버시험으로부터 미고결 제주해사의 콘선단저항-상대밀도-연직구속압의 관계를 결정하였다. 또한 현장 표준관입시험, 콘관입시험, Suspension-PS 검층을 수행하여 제주인근 해역 퇴적층의 고결가능성을 평가하였다. 시험결과, 제주해사는 입자의 각진 정도가 크고 입자표면과 내부에 공극이 발달하여 최대, 최소간극비가 큰 탄산염 모래의 특성을 가지고 있었으며, 큰 압축성을 가진 규산염 모래와 유사한 콘선단저항 분포를 나타내었다. 그러나 미고결 제주해사의 $q_c-D_R-{\sigma}_v'$ 관계는 제주인근 해역 퇴적층의 상대밀도를 과대평가하였다. 관입시험(CPT, SPT) 결과와 Suspension-PS 시험에 의한 미소변형전단탄성계수를 비교한 결과, 제주인근 해역의 퇴적층은 고결 가능성이 매우 높은 것으로 확인되었다.