• Korea-Australia Rheology Journal
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• 제13권2호
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• pp.67-81
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• 2001

The development of new techniques for the dynamic measurement of linear viscoelastic properties is an active area of rheometry, and this paper surveys some novel deformation geometries which have been recently reported e.g. oscillating probe-type devices which are imbedded in or placed on the surface of the sample. Small amplitude band-limited pseudorandom noise is used for the displacement signal, with Fourier analysis of the complex waveform of the resistance force yielding the frequency dependent viscoelastic material functions (e.g. storage and loss moduli G", G"). Theoretical calculations of the fundamental equations relating force to displacement and instrument geometry, were carried out with the aid of the correspondence principle of linear viscoelasticity. The rapidity of the tests and flexibility in terms of sample preparation and stiffness mean that this basic technique should find many applications in rheometry. Three examples of oscillatory tests are presented in detail squeeze flow, imbedded needle and concentric sliding cylinder geometries.eometries.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.527-532
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• 1997

Design strength of structural members could be determined by applying a strength reduction factor to nominal strength. At the beginning point of the transition region for the strength reduction factor, P=0.1$\sigma$$_{ck}A_g$, only sectional area and concrete strength are adopted as the variables of P=0.1$\sigma$$_{ck}A_g$. Therefore, P=0.1$\sigma$$_{ck}A_g$ is the empirically adopted which does not consider steel ratio, steel yielding stress, and steel arrangement. So, this research was perpormed the computer program for the analysis of axial force-moment-curvature relationship of reinforced concrete columns by sectional behaviour nonlinear analysis using a concrete compressive stress-strain curve, in order to investigate the ductility of reinforced concrete columns. As a result, ductility indicies of axial force, P=0.1$\sigma$$_{ck}A_g$, represented the lack of consistency of the indicies value for the various sections.

• 한국컴퓨터그래픽스학회논문지
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• 제1권2호
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• pp.201-212
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• 1995

This paper presents a new method of dynamics-based synthesis of bipedal, especially human, walking. The motion of the body at a time point is determined by ground reaction force and torque under the support foot and joint torques of the body at that time point. Motion synthesis involves specifying conditions that constrain ground reaction force and torque, and joint torques so that a given desired motion may be achieved. There are conditions on a desired motion which end-users can think of easily, e.g. the goal position and orientation of the swing foot for a single step and the time period of a single step. In this paper, we specify constraints on the motion of the support foot, which end-users would find difficult to specify. They are constraints which enforce non-sliding, non-falling, and non-spinning the support foot. They are specified in terms of joint torques and ground reaction force and torque. To satisfy them, both joint torques and ground reaction force and torque should be determined appropriately. The constraints on the support foot themselves do not give any good clues as to how to determine ground reaction force and torque. For that purpose, we specify desired trajectories of the application point of vertical ground reaction force (ground pressure) and the application point of horizontal ground reaction (friction) force. The application points of vertical pressure and friction force are good control variables, because they are indicators to kinds of walking motions to synthesize. The synthesis of a bipedal walking motion, then, consists of finding a trajectory of joint torques to achieve a given desired motion, so that the constraints are satisfied under the condition of the prescribed center of pressure and center of friction. Our approach is distinguished from many other approaches, e.g. the inverted-pendulum approach, in that it captures and formulates dynamics of the support foot and reasonable constraints on it.

• 한국콘텐츠학회논문지
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• 제8권7호
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• pp.233-242
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• 2008

종사원의 선발, 교육, 보상, 그리고 평가 등과 같은 영업사원의 관리의 실행은 영업력 관리시스템에 있어서 중요한 위치를 차지하는데, 이는 종사원의 역할 모호성, 직무만족, 그리고 성과 등에 지대한 영향을 미치기 때문이다. 이러한 중요성에도 불구하고 호텔의 영업력 관리시스템에 대한 연구가 미진한 형편이다. 따라서 본 연구에서는 영업력 관리시스템(STD, 교육, 보상, 상사지원 등), 직무태도, 그리고 성과와의 영향 관계를 보다 자세히 파악하고자 하였다. 이를 위해 경로모형과 가설을 설정하고 제시하였다. 본 연구를 통하여 호텔의 영업사원과 이들의 관리를 위한 몇 가지 중요한 사항을 제시하는데 공헌하였다. 즉, 이번 연구는 호텔의 실무책임자들과 연구자들에게 새로운 관점과 시사점을 제시할 수 있었다. 먼저, 학술적 측면에서는 영업력 관리시스템에 관한 새로운 접근 방식을 제시하였다. 둘째로, 실무적 측면을 보면, 종사원의 영업성과와 직무만족을 향상시키고, 역할모호성을 감소시키기 위하여, 관리자는 종사원을 대상으로 격려, 영업에 대한 지도, 그리고 영업 노하우 등에 교육과 행동을 취해야 한다.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1713-1719
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• 2014

1FSD is a 28-residue designed protein with a ${\beta}{\beta}{\alpha}$ motif. Since this protein displays most essential features of protein structures in such a small size, this model protein can be an outstanding system for evaluating the balance in the propensity of the secondary structures and the quality of all-atom protein force fields. Particularly, this protein would be difficult to fold to its correct native structure without establishing proper balances between the secondary structure elements in all-atom energy functions. In this work, a series of the recently optimized five amber protein force fields [$ff03^*$, $f99sb^*$-ildn, ff99sb-${\phi}^{\prime}$-ildn, ff99sb-nmr1-ildn, ff99sb-${\Phi}{\Psi}$(G24, CS)-ildn] were investigated for the simulations of 1FSD using a conventional molecular dynamics (MD) and a biased-exchange meta-dynamics (BEMD) methods. Among those tested force fields, we found that ff99sb-nmr1-ildn and ff99sb-${\Phi}{\Psi}$(G24, CS)-ildn are promising in that both force fields can locate the native state of 1FSD with a high accuracy (backbone rmsd ${\leq}1.7{\AA}$) in the global free energy minimum basin with a reasonable energetics conforming to a previous circular dichroism (CD) experiment. Furthermore, both force fields led to a common set of two distinct folding pathways with a heterogeneous nature of the transition state to the folding. We anticipate that these force fields are reasonably well balanced, thereby transferable to many other protein folds.

• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1466-1473
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• 2013

This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

• 한국정밀공학회지
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• 제14권1호
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• pp.78-83
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• 1997

The paper presents the experimental analysis of a Stewart platform-based force-torque senor. The closed-form solution of forward kinematics of the Stewart platform is derived approximately by way of a linearization technique, and the solution is used in the force analysis of the force-torque sensor. An exper- mental studies show that the proposed method including gravity compensation algorithm is valid for Stew- art platform-based force-torque sensors. The performance of the developed force-torque sensor is evaluated in view of accuracy and linearity in measurements.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.11-12
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• 2007

• 한국식품영양과학회지
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• 제41권6호
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• pp.829-833
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• 2012

느타리버섯을 생고기와 익힌 고기에 30분간 도포하여 연육효과를 조사한 결과, 상당한 연육효과가 있는 것으로 나타났다. 생고기의 경우, 버섯 무첨가 시 소고기와 돼지고기의 경도가 각각 981, 640 g-force인데 비해, 전체 5% 첨가군 소고기와 돼지고기의 경도는 각각 648, 487 g-force이었고, 갓 5% 첨가군 소고기와 돼지고기는 각각 642, 478 g-force, 줄기 5% 첨가군 소고기와 돼지고기는 각각 657, 488 g-force로 전반적인 버섯 첨가에 의한 연육효과는 약 20~35%이었다. 연육효과는 첨가량이 많을수록 커, 느타리버섯분말 5% 첨가군과 버섯추출분말 2% 첨가군의 경도가 가장 낮았다. 소고기와 돼지고기의 아미노태질소량은 버섯첨가량이 많을수록 증가하였다. 특히 버섯분말 5% 첨가한 생소고기의 아미노태질소량은 무첨가군에 비하여 전체가 34.64%(748 mg%), 갓이 34.64%(748 mg%), 줄기가 32.92%(739 mg%) 증가하였고, 버섯추출분말 2% 첨가한 생소고기는 전체가 65.14%(787 mg%), 갓이 75.21%(834 mg%), 줄기가 71.18%(815 mg%) 증가하였다. 이는 느타리버섯분말과 추출분말이소고기의 단백질을 가수분해하여 수용성 성분이 증가된 것으로 사료된다. 버섯전체, 갓, 줄기의 부위별 연육효과는 별 차이가 없어 사용부위는 굳이 구별할 필요가 없는 것으로 나타났다.

• 한국방재학회 논문집
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• 제7권1호통권24호
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• pp.1-9
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• 2007

본 연구는 국내에 시공된 조적조 건축물의 특징을 반영한 조적벽체의 반복가력과 모의진동대 실험을 통해 얻어진 결과를 근거로 하여 유리섬유로 보강된 보강조적벽체의 전단내력식을 제안하는 것을 목적으로 한다. 실험결과, 개구부가 없는 조적벽체의 파괴를 지배하는 모드는 Rocking이였고, 개구부가 있는 경우는 개구부 주변에 균열이 집중되었다. 비보강 조적벽체의 전단내력식은 UBC에서 제시한 식이 실험과 가장 유사한 값을 보였다. 본 연구를 통해 제안되어지는 유리섬유 보강조적벽체의 전단내력식은 다음과 같다. $$V_n=0.02A_n{\sqrt{f'_m}}+0.022b_gh_g(1+2{\alpha})^3{\sqrt{f_g}}(N/mm^2)$$.