• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1392-1400
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• 1995

WC-10wt%Co-Al2O3 ceramic composites, using both the SHS (Self-propagating High Temperature Synthesis) synthesized WC powder method and commercial WC powder, were prepared by varing WC-Co/Al2O3 vol% ratio and sintering temperature (1350℃∼1650℃) for 1 hr in Ar atmosphere. Mechanical characterization has been investigated by Instron meterial testing system and Vicker's hardness test. Compositional and structural chracterizations were carried out by energy-dispersive analysis of X-ray (EDAX) data and scanning electron microscope (SEM). Electrical characterization was carried out by the electrical resistivity measurement using 4-point probe method. As sintering period increased and Al2O3 contents decreased in WC-10wt%Co-Al2O3 ceramic composite, shrinkage and relative density increased, resulting in maximum values at 1600℃. Also the major matrix phase changed with increasing Al2O3 content from 0 to 100 vol%. It was also identified by SEM, EDAX, and electrical resistivity measurement. Based on the results of analysis of flexural strength, toughness and hardness, the mechanical properties of WC-10wt%Co-Al2O3 ceramic composites using the SHS synthesized WC powder were better than those WC-10wt%Co-Al2O3 ceramic composites using commercial WC powder because WC-10wt%Co-Al2O3 ceramic composites using the SHS synthesized WC powder were sintered very well due to small initial particle size. By the addition of 40 vol% Al2O3 [60(WC=10wt%Co)-40Al2O3], it was possible to obtain a proper candidate as a superalloy.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.3
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• pp.1-10
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• 2015

Objectives : The purpose of this study was to reveal the prevalence of Mibyeong and its symptoms including fatigue, pain, sleep disturbance, dyspepsia, depression, anxiety and anger by using the national survey. Methods : Questionnaires were collected by Gallup Korea. Participants were chosen through stratified sampling method based on area, gender and age. Questionnaire was designated to confirm the recognition, managing of Mibyeong, investigation of life habit, medical history, basic information, QoL questionnaires (Short Form-12, EuroQol-5D) and understanding of Mibyeong medical service conditions. Generally all questionnaires were used for survey the Mibyeong status in public except QoL questionnaires. Questionnaires were fulfilled by professional surveyor as face to face interview. Descriptives was used for data analysis and the results were expressed as percentage ratios (%) Results : 1,101 of people were acquired in this study. Eighty point two (80.2%) percent of participants did not know the concept of Mibyeong accurately even though 80.6% complained of Mibyeong related symptoms. Among them, fatigue was accounted for the highest response (70.7%)in this study. Sixty point four percent of participants identified non-smoking, stop drinking, eating habits and sleeping habits as a way to manage their Mibyeong related symptoms. In addition, exercising (60.8%), visiting medical institution (58.4%) and taking health functional food (52.7%) were presented. Only 23.1% among people with symptoms Mibyeong visited medical facilities. Moreover, the quality of life was found to be significantly correlated with health status. Conclusions : This study could contribute to express the importance of announcing the concept of Mibyeong and status to Korean public. Moreover, more Mibyeong studies should be conducted in the future to evaluate the Mibyeong status objectively.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.1
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• pp.101-110
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• 2004

The robots that will be needed in the near future are human-friendly robots that are able to coexist with humans and support humans effectively. To realize this, humans and robots need to be in close proximity to each other as much as possible. Moreover, it is necessary for their interactions to occur naturally. It is desirable for a robot to carry out human following, as one of the human-affinitive movements. The human-following robot requires several techniques: the recognition of the moving objects, the feature extraction and visual tracking, and the trajectory generation for following a human stably. In this research, a predictable intelligent space is used in order to achieve these goals. An intelligent space is a 3-D environment in which many sensors and intelligent devices are distributed. Mobile robots exist in this space as physical agents providing humans with services. A mobile robot is controlled to follow a walking human using distributed intelligent sensors as stably and precisely as possible. The moving objects is assumed to be a point-object and projected onto an image plane to form a geometrical constraint equation that provides position data of the object based on the kinematics of the intelligent space. Uncertainties in the position estimation caused by the point-object assumption are compensated using the Kalman filter. To generate the shortest time trajectory to follow the walking human, the linear and angular velocities are estimated and utilized. The computer simulation and experimental results of estimating and following of the walking human with the mobile robot are presented.

• Korean Journal of Optics and Photonics
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• v.27 no.4
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• pp.133-142
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• 2016

This paper presents the design and simulation of a three-dimensional pixel-by-pixel scanning light detection and ranging (LIDAR) system with a microelectromechanical system (MEMS) scanning mirror and direct sequence optical code division multiple access (DS-OCDMA) techniques. It measures a frame with $848{\times}480$ pixels at a refresh rate of 60 fps. The emitted laser pulse waves of each pixel are coded with DS-OCDMA techniques. The coded laser pulse waves include the pixel's position in the frame, and a checksum. The LIDAR emits the coded laser pulse waves periodically, without idle listening time to receive returning light at the receiver. The MEMS scanning mirror is used to deflect and steer the coded laser pulse waves to a specific target point. When all the pixels in a frame have been processed, the travel time is used by the pixel-by-pixel scanning LIDAR to generate point cloud data as the measured result.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.3
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• pp.12-18
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• 1994

Optimization in the engineering design is to select the best of many possible design alternatives in a complex design space. In order to optimize, various optimization methods have been used. One major problem of traditional optimization methods is that they often result in local optima. Recently genetic algorithm based on the mechanics of natural selection and natural genetics is used in many application fields for optimization. Genetic algorithm is more powerful to local optima, but it requires more calculation time and has difficulties in finding exact optimum point in design variable with real data type generally. In this paper. hybrid method was developed by coupling genetic algorithm and traditional direct search method. The developed method finds out a region for global optimum using genetic algorithm, and is to search global optimum using direct search method based on results obtained from genetic algorithm. By using hybrid method, calculation time is reduced and search efficient for optimum point is increased.

• Journal of Nutrition and Health
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• v.35 no.3
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• pp.394-401
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• 2002

The purpose of this study was to : (a) examine diabetic patients' sensory evaluation and food preferences, (b) analyze the portion sizes & plate wastes, (c) investigate the factors affecting plate wastes, and (d) determine the nutritional & mometary values of the plate wastes. A questionnaire for determining food preference and sensory evaluation was developed. Thirty-three diabetic patients who were hospitalized in Sanggye Paik hospital in Seoul were studied. Serving sizes and plate wastes were weighed by using an electric scale, and the CAN-Pro program was used to evaluate the nutritional value or the food consumed. The data were analyzed using the SAS package program for descriptive analysis, t-test, ANOVA, and the Pearson correlation. Using a five-point Likeu-type scale, the temperature s[ore ranged from 3.1 to 3.3 (1 : very poor, 5 : excellent), the preference store was 3.0-3.2 (1 : very dislike, 5:very like), the taste score was 2.9-3.2 (1 : very poor, 5 : excellent), and the amount of food served score was 2.8-3.0 (1 : too little, 5 : too much). Serving sizes were considered insufficient by patients because most of the DM diet was low in calories. Average plate waste for the DM diet was 26.2% of the total served, by weight, and was lower than that for patients consuming a normal diet, which was 30.3%, found in previous research. Those subjects who had been previously hospitalized and who wished to participate in a campaign for food waste reduction produced less plate waste than other groups (p<.05). Plate wastes of the DM diet were negatively correlated with taste, temperature, and preference, and were positively correlated with the amount served: however, these results were not statistically significant. It was found that diabetic patients consumed adequate levels of energy, protein, Ca, Fe, Vitamin B$_1$, Vitamin B$_2$, and niacin, but inadequate levels of Phosphorus, Vitamin A and Vitamin C. The plate wastes were calculated to be 26.2% of the total cost (￦ 3,489), which is ￦9l5. This represents a significant wastage of resources from the hospital. The results of this study could assist foodservice managers in both controlling food wastage, and improving the quality of hospital food services.

• Journal of Intelligence and Information Systems
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• v.28 no.3
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• pp.237-258
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• 2022

As the global market environment changes, the domestic ICT industry has a growing influence on the world economy. This industry is regarded as an important driving force in the national economy from a technological and social point of view. In particular, small and medium-sized enterprises (SMEs) in the ICT industry are regarded as essential actors of domestic economic development in terms of company diversity, technology development and job creation. However, since it is small compared to large-sized enterprises, it is difficult for SMEs to survive with a differentiated strategy in an incomplete and rapidly changing environment. Therefore, SMEs must make a lot of efforts to improve their own capabilities, and the government needs to provide the desirable help suitable for corporate internal resources so that they can continue to be competitive. This study classifies the types of ICT SMEs participating in government support programs, and analyzes the relationship between resources and performance creation of each type. The data from the "ICT Small and Medium Enterprises Survey" conducted annually by the Ministry of Science and ICT was used. In the first stage, ICT SMEs were clustered based on common factors according to their experiences with government support programs. Three clusters were meaningfully classified, and each cluster was named "active participation type," "initial support type," and "soloist type." As a second step, this study compared the characteristics of each cluster through profiling analysis for each cluster. The third step carried out in this study was to find out the mechanism of R&D performance creation for each cluster through regression analysis. Different factors affected performance creation for each cluster, and the magnitude of the influence was also different. Specifically, for "active participation type", "current manpower", "technology competitiveness", and "R&D investment in the previous year" were found to be important factors in creating R&D performance. "Initial support type" was identified as "whether or not a dedicated R&D organization exists", "R&D investment amount in the previous year", "Ratio of sales to large companies", and "Ratio of vendors supplied to large companies" contributed to the performance. Lastly, in the case of "soloist type", "current workforce" and "future recruitment plan", "technological competitiveness", "R&D investment", "large company sales ratio", and "overseas sales ratio" showed a significant relationship with the performance. This study has practical implications of showing what strategy should be established when supporting SMEs in the future according to the government's participation in the startup program and providing a guide on what kind of support should be provided.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.2
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• pp.143-152
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• 2012

It is well-known that image matching is necessary for automatic generation of 3D data such as digital surface data from aerial images. Recently developed aerial digital cameras allow to capture multi-strip images with higher overlaps and less occluded areas than conventional analogue cameras and that much of researches on multi-image matching have been performed, particularly effective methods of measuring a similarity among multi-images using point features as well as linear features. This research aims to investigate similarity measuring methods such as SSD and SNCC incorporated into a area based multi-image matching method based on vertical line locus. In doing this, different similarity measuring entities such as grey value, grey value gradient, and average of grey value and its gradient are implemented and analyzed. Further, both dynamic and pre-fixed adaptive-window size are tested and analyzed in their behaviors in measuring similarity among multi-images. The aerial images used in the experiments were taken by a DMC aerial frame camera in three strips. The over-lap and side-lap are about 80% and 60%, respectively. In the experiment, it was found that the SNCC as similarity measuring method, the average of grey value and its gradient as similarity measuring entity, and dynamic adaptive-window size can be best fit to measuring area-based similarity in area based multi-image matching method based on vertical line locus.

• Korean Journal of Computational Design and Engineering
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• v.16 no.4
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• pp.305-313
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• 2011

This paper proposes a method for reusing kinematic design data for virtual facilities, Making a virtual model of a facility involves two major activities: geometric design (virtual model visualization) and kinematic design that should be remodeled frequently whenever design changes occur, Conventionally, a virtual model of an automated facility focuses on the design level, which mainly deals with design verification, alternative comparison, and geometric model diagnosis, Although a design level model can be designed with the information of past models from PLM system, a simulation level model is not sufficient utilized to be reused for kinematic design purpose, We propose a method for reusing kinematic information of a past simulation model to cope with this problem, We use the concept or the 'center of mass', which is a point representing the mean position of the matter in a body or system. And we also use comparison method of a boundary box to identity which 3D objects have to be involved from the design model to a link structure that is contained in the simulation model. Because a proposed method only use not a historical approach but a geometrical approach, it is more effective to apply to the field.

• Journal of Korean Academy of Nursing Administration
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• v.12 no.1
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• pp.131-139
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• 2006

Purpose: This study was carried out to understand the degree of moral distress of nurses and to provide scientific data for searching measures to efficiently manage their moral distress. Method: The survey was conducted with 302 nurses at the general hospital in City D by using the self-report type of questionnaire composed of 66 questions of 5-point Likert scale in four dimensions. Result: The mean scores of moral distress of nurses showed higher than average in all four dimensions: $80.54{\pm}14.82$ of 150 in the situational dimension, $52.99{\pm}9.98$ of 90 in the cognitive dimension, $13.30{\pm}2.85$ of 25 in the behavioral dimension, and $48.06{\pm}7.76$ of 65 in the emotional dimension. In addition, moral stress of each factor in the situational area showed $34.20{\pm}7.27$ in negative medical behavior, $10.98{\pm}2.53$ in lack of respect for autonomy of patients, excessive economic burden $10.86{\pm}2.94$, $7.40{\pm}1.89$ in irrational organizational administration and $17.10{\pm}3.50$ in negative nursing behavior. Conclusion: It is necessary to develop the intervention program to help nurses to reduce their moral distress since its degree showed considerably high.