• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.83-91
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• 2008

Previous settlement prediction methods based on settlement monitoring were developed under instantaneous loading condition and have restriction to be applied to soft ground under ramp loading condition. In this study, settlement prediction method under ramp loading was developed. New settlement prediction method under ramp loading considered influence factors of consolidation settlement such as thickness of clayed layer, quantity of surcharge load and preconsolidation pressure, etc. Geometrical correction method based on hyperbolic method (1991) and correction method based on probability theory were applied to increase accuracy of settlement prediction using field monitoring data after ramp loading. Large consolidation tests for ideally controlled one dimensional consolidation under ramp loading condition were performed and the settlement behavior was predicted based on the monitoring data. New prediction method yielded good result of entire settlement behavior by using data during an early stage of ramp load. Additionally, new prediction method offered better settlement prediction which had final settlement prediction in close proximity and low RMSE(Root Mean Square Error) than previous method such as hyperbolic method did.

• Journal of Fashion Business
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• v.16 no.5
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• pp.207-219
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• 2012

It is intended to study the colors of work environment and the working clothes colors between humans and environment with application of the arrangement of working clothes colors to domestic machinery companies that play pivotal roles in the industry of Korea. The purpose of this study is to provide the foundation of color plan for the integrated environmental harmonization and the safety of industrial sites by analyzing the photographs of working clothes in the sires in consideration of the functions of colors (clearness, attention-getting, and safety) using the Faber Birren's Color Harmony and by analyzing the result of a questionnaire survey. The study was conducted by the method to shoot a worksite using a digital camera after wearing 24 sets of uniforms, which were developed by the color plan established in a previous study, in the same worksite. The shooting place was an outdoor steel sheet inspection site of D company, a machinery company in Changwon-si, Gyeongnam, and the intensity of illumination was 2400lux. 24 pieces of images were printed in 5x7 inch size and a questionnaire survey was performed at 5-point scale. The questionnaire survey was performed for 13 subjects consisting of 6 field professionals having more than 30 years of experiences, 4 clothes color professionals, and 3 industrial engineering professionals. The result of the survey was statistically analyzed by the method of frequency analysis using IBM SPSS Statistics 20 Program. As the result of assessment of basic four colors (yellow green, sky blue, blue, and violet) of working clothes, yellow green, sky blue, and blue showed high mean values in (Tint)+(Shade)+(Tone)+(Gray) equation indicating that its is a harmonized equation.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.83-93
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• 2003

This research, in order to study the effects of initial shear stress of anisotropically consolidated sand that has 0.558% fines, performed several undrained static and dynamic triaxial test. To simulate the real field conditions, loose and dense samples were prepared. Besides, the cyclic shear strength of Nakdong River sand under various combinations of initial static shear stress, stress path, pore water pressure and residual strength relationship was studied. By using Bolton's theory, peak internal friction angle at failure which has considerable effects on the relative density and mean effective stress was determined. In p'- q diagram, the phase transformation line moves closer to the failure line as the specimen's initial anistropical consolidation stress increases. Loose sands were more affected than dense sands. The increase of consolidation stress ratio from 1.4 to 1.8 had an effect on liquefaction resistance strength resulting from the increase of relativity density, and showed similar CSR values in dense specimen condition.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.47-53
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• 2015

This paper is to study applying for numerical analysis method for flow field, velocity and pressure of fuel on the low pressure pump using excavator. The pressure distribution of fuel pump certified the linear variation according to rotation angle of rotor. Especially, it knew the fact that the pressure in rotation angle $40^{\circ}$ appeared high outlet and low inlet of fuel pump. Also, this range angle can seek the fact that the leakage flow and velocity are the most increasing. And the more rotor rotation of fuel pump, the more mean outlet flow rate increased in linear. Whenever the gap size decrease with rotor and housing, the discharge flow rate could seek the approaching 0.0712kg/s that consider with theory discharge flow rate calculated from displacement between rotor gear and idle gear.

• Smart Structures and Systems
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• v.9 no.6
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• pp.505-534
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• 2012

The present work deals with second order statistics of post buckling response of piezoelectric laminated composite cylindrical shell panel subjected to hygro-thermo-electro-mechanical loading with random system properties. System parameters such as the material properties, thermal expansion coefficients and lamina plate thickness are assumed to be independent of the temperature and electric field and modeled as random variables. The piezoelectric material is used in the forms of layers surface bonded on the layers of laminated composite shell panel. The mathematical formulation is based on higher order shear deformation shell theory (HSDT) with von-Karman nonlinear kinematics. A efficient $C^0$ nonlinear finite element method based on direct iterative procedure in conjunction with a first order perturbation approach (FOPT) is developed for the implementation of the proposed problems in random environment and is employed to evaluate the second order statistics (mean and variance) of the post buckling load of piezoelectric laminated cylindrical shell panel. Typical numerical results are presented to examine the effect of various environmental conditions, amplitude ratios, electrical voltages, panel side to thickness ratios, aspect ratios, boundary conditions, curvature to side ratios, lamination schemes and types of loadings with random system properties. It is observed that the piezoelectric effect has a significant influence on the stochastic post buckling response of composite shell panel under various loading conditions and some new results are presented to demonstrate the applications of present work. The results obtained using the present solution approach is validated with those results available in the literature and also with independent Monte Carlo Simulation (MCS).

• Steel and Composite Structures
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• v.39 no.2
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• pp.215-228
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• 2021

This paper investigates the effect of micromechanical models on the bending behavior of bidirectional functionally graded (BDFG) beams subjected to different mechanical loading. The material properties of the beam are considered to be graded in both axial and thickness directions according to a power law. The beam's behavior is modeled by the mean of quasi 3D displacement field that contain undetermined integral terms and involves a reduced unknown functions. Navier's method is employed to determine and compute the displacements and stress for a simply supported beam. Different homogenization schemes such as Voigt, Reus, and Mori-Tanaka are employed to analyze the response of the BDFG beam subjected to linear, uniform, exponential and sinusoidal distributed loading. The results obtained by the present method are compared with available results in the literature and a good agreement was found. Several numerical results are presented in tabular form and in figures to examine the effects of the material gradation, micromechanical models and types of loading on the bending response of BDFG beams. It can be concluded that the present theory is not only accurate but also simple in predicting the bending response of BDFG beam subjected to different static loads.

• Journal of Educational Research in Mathematics
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• v.27 no.1
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• pp.113-135
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• 2017

The purpose of the research was to develop an analysis framework for Korean mathematics textbooks from a critical mathematics education perspective. For this, we conducted a comprehensive literature review regarding critical theory, critical education, and critical mathematics education. Based on the literature review, we derived a preliminary framework for textbook analysis. To validate the preliminary framework delphi survey was carried out twice with 21 expert panelists in the field of mathematics education and multicultural education. The first delphi survey was conducted with open-ended questions to investigate diverse opinions regarding educational goals, contents, and teaching methods of critical mathematics education. The second delphi survey was conducted with Likert-type scale and it was analyzed using Mean, Contents Validity Ratio, Degree of Consensus. As the result of the whole research procedures, the final analysis framework was developed consisting of four categories: classical knowledge, community knowledge, communicative knowledge, and political knowledge. A development of the analysis framework from a critical mathematics education perspective could give a significant impact on the mathematics curriculum or mathematic teacher education in the Korea and a meaningful initial step for the effort of practicing critical mathematics education. It is expected that this study could not only incite consideration for the better mathematics education but also expand the prospect of research and practice in mathematics education. This study would provide a new paradigm of future mathematics education with which to teach and guide students to become members of world civil society with mathematical power and critical competency.

• Journal of Korean Foot and Ankle Society
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• v.15 no.4
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• pp.223-231
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• 2011

Purpose: Pathogenesis of intraneural ganglion is controversial, however, the synovial theory that the intraarticular region is the origination of disease has come into the spotlight nowadays. But there are a few researches about intraneural ganglion in foot and ankle. We studied 7cases of intraneural ganglion. We are going to prove the synovial theory by indentifying articular branch of intraneural ganglion. Materials and Methods: From August 2003 to May 2011, we evaluated 7 ouf of 8 patients diagnosed as a intraneural ganglion in foot and ankle. The gender ratio were 4 male and 3 female, and the mean age at the time of surgery was 52.9 years. Clinically, we checked pre and post operative symptom, muscle tone and whether loss of muscle tone and sensation exists. We analyzed surgical records and preoperative MRI and compared those with intra-operative finding. Results: In MRI analysis of 7cases, the connection around the joints were confirmed, and 1 case was confirmed in the retrospective analysis of MRI. Intraneural ganglions occurred in medial plantar nerve 3 cases, lateral plantar nerve 1 case, superficial peroneal nerve 1 case and sural nerve 1 case. We could not found recurrence during the follow up periods. Most patients relieved pain after operation, but recovery of sensation was unsatisfactory. We could find some cases pathological finding of the nerve intraoperatively, and clinical result of that cases was poor. Conclusion: Intraneural ganglion can occur in various parts in foot and ankle. We concluded that the intranneural ganglion originated from joint by identifying the artichlar branch of ganglion. Due to its small size, it is difficult to find articular branch in operation field. But we do our best to find and remove articular branch. Currently, considering the small amount of research in foot and ankle, more research about articular brach is needed.

• Journal of Korean Theatre Studies Association
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• no.40
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• pp.503-535
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• 2010

'Saiee', which could mean between, intra- and inter-, is a crucial topic in theatre as theatre has tension between actor and audience, reality and illusion, and everyday life and extraordinary life. Especially, it is interesting that the function of 'Saiee' is connected to extension and application of drama and theatre such as educational theatre, dramatherapy and applied drama/theatre. Such works are expected to educational or therapeutic effects, thus concern and support, demand and supply of these works is getting increased. However, it is true that researches on spirit, aesthetic and direction of these works are not sufficient, compared to quantitative increase and diversity. This study will explore Boal's Theatre of the Oppressed(TO from the below), which is key theory and technique of applied drama/theatre field with viewpoint of 'Saiee' theatre to look at spirit, aesthetic and direction of this field. Saiee's energy could observe the object with distance(distance), form the relationship with that object(inter) and create new circumstance through that relationship(intra). And Boal's TO tried to Saiee's theatre by using Saiee's dynamics variously. It bases on the phenomenon of metaxis. Boal's TO believes that drama/theatre is unique nature and ability of human being, that is to say, it is based on Homo Theatrum, human plays and does theatre. Therefore, the participant of Boal's TO is extended to everyone in everyday life. This activity is not only individual work to find his/her identity but also solidarity and possibility to change society which they belong to. It is the dynamics of 'Saiee' to make this possible. Boal's TO thinks that relationship and balance between individuality and sociality is important. The way of conversation in Boal's TO includes questioning, listening and communication. Unfamiliarity or distance of 'Saiee' makes interest in other people and question about them. Questioning through theatre and concern on other beings to search for the answer (this is listening), would be new relationship(and possibility) to extend him/herself. The communication and relationship leads to possibility and ability to create another world. This is the function of 'inter-' and 'intra-' in theatre of 'Saiee'. Lastly, it is various that Boal's TO as 'Saiee' theatre uses the dynamics of 'Saiee'. The diversity of technique comes from the application to humans in every moment and every time. To apply 'Saiee's aesthetic actively, concern and research on people 'now and here' should be proceed.

• Journal of the Korean Magnetics Society
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• v.11 no.3
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• pp.85-96
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• 2001

Experimental magnetization-temperature curves for melt-spun ribbons of amorphous alloys (Dy$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0 ,0.05, 0.1, and 0.15) and (Sm$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0, 0.01, 0.02, and 0.03) (in atomic fraction) are fitted with theoretical equations based on the mean field theory in order to calculate exchange couplings between constituent elements as a function of the B content. In the case of the DyFe$_2$-B system, the sign of the exchange coupling between Dy and Fe is negative, indicating that the magnetization direction of Dy is antiparallel to that of Fe. The sign of the other two couplings are positive indicating a parallel alignment. The exchange coupling between Fe ions are greatest, while that between Dy ions is negligible. In the case of the SmFe$_2$B alloys, the sign of all the couplings are positive, indicating ferromagnetic coupling between the spins. The exchange couplings between Fe ions, and Fe and Sm are comparable to each other, but they are much greater than that between Sm ions. The high exchange coupling between Fe and Sm, which is considered to occur indirectly, is rather unexpected, but it is considered to be unique characteristics of amorphous Sm-Fe alloys. In both alloy systems, the exchange coupling between Fe ions increases with increasing B content. and this may be explained by the increase of the Fe-Fe separation with increasing B content. The exchange coupling between Fe and RE also increases with increasing B content. As the B content increases, the magnetization decreases over the whole temperature range, and the Curie temperature also decreases.