• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.118-125
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• 2002

Hydration is the main reason for the growth of the material properties. An exact parameter to control the chemical and physical process is not the time, but the degree of hydration. Therefore, it is reasonable that development of all material properties and the formation of microstructure should be formulated in terms of degree of hydration. Mathematical formulation of degree of hydration is based on combination of reaction rate functions. The effect of moisture conditions as well as temperature on the rate of reaction is considered in the degree of hydration model. This effect is subdivided into two contributions: water shortage and water distribution. The former is associated with the effect of W/C ratio on the progress of hydration. The water needed for progress of hydration do not exist and there is not enough space for the reaction products to form. The tatter is associated with the effect of free capillary water distribution in the pore system. Physically absorption layer does not contribute to progress of hydration and only free water is available for further hydration. In this study, the effects of chemical composition of cement, W/C ratio, temperature, and moisture conditions on the degree of hydration are considered. Parameters that can be used to indicate or approximate the real degree of hydration are liberated heat of hydration, amount of chemically bound water, and chemical shrinkage, etc. Thus, the degree of heat liberation and adiabatic temperature rise could be determined by prediction of degree of hydration.

• Journal of the Korean Institute of Intelligent Systems
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• v.5 no.1
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• pp.52-64
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• 1995

Robot manipulator is a highly nonlinear-time varying system. Therefore, a lot of control theory has been applied to the system. Robot manipulator has two types of control; one is path planning, another is path tracking. In this paper, we select the path tracking, and for this purpose, propose the intelligent control¬ler which is combined with fuzzy logic and neural network. The fuzzy logic provides an inference morphorlogy that enables approximate human reasoning to apply to knowledge-based systems, and also provides a mathematical strength to capture the uncertainties associated with human cognitive processes like thinking and reasoning. Based on this fuzzy logic, the fuzzy logic controller(FLC) provides a means of converhng a linguistic control strategy based on expert knowledge into automahc control strategy. But the construction of rule-base for a nonlinear hme-varying system such as robot, becomes much more com¬plicated because of model uncertainty and parameter variations. To cope with these problems, a auto-tuning method of the fuzzy rule-base is required. In this paper, the GA-based Fuzzy-Neural control system combining Fuzzy-Neural control theory with the genetic algorithm(GA), that is known to be very effective in the optimization problem, will be proposed. The effectiveness of the proposed control system will be demonstrated by computer simulations using a two degree of freedom robot manipulator.

• The Korean Journal of Elementary Counseling
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• v.9 no.2
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• pp.143-162
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• 2010

The purpose of this study is to construct Parent Attachment Scale for Children. Adapting the item consisting method used in Experiences in Close Relationships-Revised(ECR-R), Parent Attachment Scale for Children was constructed to measure child's attachment style with their parent, reliably and validly. Also, reliability and item trait informations based on item response theory were reviewed. First preliminary items were derived from the original items of ECR-R and existing Attachment Inventories. These items were modified and complemented to be easier and keep the original meaning of each item. Second preliminary items were administrated to 4~6th grades students(N=576). Finally, Parent Attachment Scale for Children were consisted with 30 items based on two-parameter graded response model. Internal consistency ranges of the scales of Parent Attachment Scale for Children are as follows : Avoidance scale is .94~.96; Anxiety scale is .85~.88. Test-retest reliability ranges are as follows; Avoidance scale is .71~.80; Anxiety scale is .53~.68. Item discrimination and item information value were within an appropriated range. Hierarchical cluster analysis with Ward's Method revealed four types of attachment style : Secure, Dismissing, Preoccupied, Fearful. Other implications and limitations of this study were discussed.

• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.8-15
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• 2016

The purpose of this study is to design a model with the structural stability so as not to lose the operational function due to structural plastic or fail of a sliding blast door by blast pressure to this aim, a numerical simulation was performed using full-size experiments and M&S (Modeling & Simulation) of the sliding blast door. The sliding blast door ($W3,000{\times}H2,500mm$) under the blast load is in the form of a sliding type 2-way metal grill, which was applied by a design blast pressure (reflected pressure $P_r$) of 17 bar. According to the experimental results of a real sliding blast door under blast load, the blast pressure reached the sliding blast door approximately 4.3 ms after the explosion and lasted about 4.0 ms thereafter. The maximum blast pressure($P_r$) was 347.7 psi (2,397.3 kPa), it is similar to the UFC 3-340-02 of Parameter(91 %). In addition, operation inspection that was conducted for the sliding blast door after real test showed a problem of losing the door opening function, which was because of the fail of the Reversal Bolt that was installed to prevent the shock due to rebound of the blast door from the blast pressure. According to the reproduction of the experiment through M&S by applying the blast pressure measurement value of the full-size experiments, the sliding blast door showed a similar result to the full-size experiment in that the reversal bolt part failed to lose the function. In addition, as the pressure is concentrated on the failed reversal bolt, the Principal Tensile Failure Stress was exceeded in only 1.25 ms after the explosion, and the reversal bolt completely failed after 5.4 ms. Based on the result of the failed reversal bolt through the full-size experiment and M&S, the shape and size of the bolts were changed to re-design the M&S and re-analyze the sliding blast door. According to the M&S re-analysis result when the reversal bolt was designed in a square of 25 mm ($625mm^2$), the maximum pressure that the reversal bolt receives showed 81% of the principal tensile failure stress of the material, in plastic stage before fail.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2511-2517
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• 2009

Recently, a FMCW radar is used for the various purposes in the short range detection and tracking of targets. The main advantages of a FMCWradar are the comparative simplicity of implementation and the low peak power transmission characterizing the very low probability of signal interception. Since it uses the frequency modulated continuous wave for transmission and demodulation, the received beat frequency represents the range and Doppler information of targets. Detection and extraction of useful information from targets are performed in this beat frequency domain. Therefore, the resolution and accuracy in the estimation of a beat spectrum are very important. However, using the conventional FFT estimation method, the high resolution spectrum estimation with a low sidelobe level is not possible if the acquisition time is very short in receiving target echoes. This kind of problems deteriorates the detection performance of adjacent targets having the large magnitude differences in return echoes and also degrades the reliability of the extracted information. Therefore, in this paper, the model parameter estimation methods such as autoregressive and eigenvector spectrum estimation are applied to mitigate these problems. Also, simulation results are compared and analyzed for further improvement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7990-8000
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• 2015

Plant factories are plant cultivation systems which produce farm products uniformly under the controlled environmental condition regardless of seasons and places. Thermal flow in the plant factory is an important parameter in cultivating plants. In this research, we study thermal flow characteristics for a hybrid plant factory with multi-layer cultivation shelves using computer simulation techniques. In order to obtain numerical solutions for thermal flow characteristics, a finite volume method was applied. We consider a low-Reynolds-number ${\kappa}-{\epsilon}$ turbulence model, incompressible viscous flows, and pressure boundary conditions for numerical simulation. Commercial software Solid Works Flow Simulation is then used to investigate characteristics of thermal flows in the plant factory applying several different inflow air velocities and arrangements of cultivation shelves. From numerical analysis results, we found that temperatures in cultivation shelves were uniformly distributed for Case 3 when the inflow air velocity was 1.6 m/s by using a blower in the plant factory. However in Case 1 lower temperature distributions were observed in test beds, TB2 and TB3, which indicated that additional temperature control efforts would be required. Average shelf temperature increased by $3^{\circ}C$ using artificial light source (DYLED47) with 50% blue and 50% red LED ratios. Korea Academia-Industrial cooperation Society.

• The Journal of Engineering Geology
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• v.12 no.4
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• pp.421-437
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• 2002

In order to quantify the anisotropic properties of rock included joints and shear behavior in joint surface, the mold is Produced for rock joint surface using gypsum Plaster and Peformed for replicated joint models made of cement mortar. Rock sample is measured using mechanical profilometer before testing and their result is expressed quantitatively. The statistical parameters and the fractal dimension by fractal theory for roughness is investigated its coordinate value for numerical process. The shear strength to the shear displacement in low level normal stress ismaintained or increased in most joint models. Their results present that this relationship is depended several roughness properties in joint model for natural rock joint. The relationship between the shear strength and the Properties for profiles estimated by some statistical parameter in roughness has the low correlation and is not constant. The result between the data for direct shear test and using Barton's equation, Barton's equation has not the effectiveness for the effect of anisotropy and has not suitable to recognizing the properties for joint surface. It means that JRC has not the properties of anisotropic rock surface. The fractal dimension is well correlated with the data of direct shear test than those of JRC. New experimental formulae using fractal dimension is comported with the anisotropic properties for direct shear test.

• Cartoon and Animation Studies
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• s.39
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• pp.393-412
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• 2015

See and feel the emotion recognition is the image of a person variously changed according to the environment, personal disposition. Thus, the image recognition has been focused on the emotional sensibilities computer you want to control the number studies. However, existing emotional computing model is numbered and the objective is clearly insufficient measurement conditions. Thus, through quantifiable image Emotion Recognition and emotion computing, is a study of the situation requires an objective assessment scheme. In this paper, the sensitivity was represented by numbered sizes quantified according to the image recognition calculation emotion. So apply the principal attributes of the color image emotion recognition as a configuration parameter. In addition, in calculating the color sensitivity by applying a digital computing focused research. Image color emotion computing research approach is the color of emotion attribute, brightness, and saturation reflects the weighted according to importance to the emotional scores. And free-degree by applying the sensitivity point to the image sensitivity formula (X), the tone (Y-axis) is calculated as a number system. There pleasure degree (X-axis), the tension and position the position of the image point that the sensitivity of the emotional coordinate crossing (Y-axis). Image color coordinates by applying the core emotional effect of Russell (Core Affect) is based on the 16 main representatives emotion. Thus, the image recognition sensitivity and compares the number size. Depending on the magnitude of the sensitivity scores demonstrate this sensitivity must change. Compare the way the images are divided up the top five of emotion recognition emotion emotions associated with 16 representatives, and representatives analyzed the concentrated emotion sizes. Future studies are needed emotional computing method of calculation to be more similar sensibility and human emotion recognition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1786-1795
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• 2011

The trajectory control for omni-directional mobile robot is not easy. Especially, the tracking control which system uncertainty problem is included is much more difficult. This paper develops trajectory controller of 3-wheels omni-directional mobile robot using fuzzy multi-layered algorithm. The fuzzy control method is able to solve the problems of classical adaptive controller and conventional fuzzy adaptive controllers. It explains the architecture of a fuzzy adaptive controller using the robust property of a fuzzy controller. The basic idea of new adaptive control scheme is that an adaptive controller can be constructed with parallel combination of robust controllers. This new adaptive controller uses a fuzzy multi-layered architecture which has several independent fuzzy controllers in parallel, each with different robust stability area. Out of several independent fuzzy controllers, the most suited one is selected by a system identifier which observes variations in the controlled system parameter. This paper proposes a design procedure which can be carried out mathematically and systematically from the model of a controlled system; related mathematical theorems and their proofs are also given. Finally, the good performance of the developed mobile robot is confirmed through live tests of path control task.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.405-411
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• 2016

Given the importance of ensuring continued residency and maintenance of the 1st Planned New Town, which is the first of more than 20 such projects, this study aims to identify the factors determining the residents' living intention. The results show that age, gender, length of stay, and occupancy type are significant factors influencing their living intention. Among the environmental factors, the educational environment and shopping environment are crucial. This means that in order to achieve the "Ageing in Place" concept, it is necessary to improve the educational environment, provide a variety of commercial facilities and expand the living facilities. While it has no direct influence on the pros and cons of building remodeling, the results showed that when the living intention is used as a parameter, the transportation, educational, and shopping environment have an indirect influence on the pros and cons of building remodeling.