• 한국HCI학회:학술대회논문집
• /
• 한국HCI학회 2008년도 학술대회 1부
• /
• pp.451-455
• /
• 2008

CUDA 는 GPGPU 프로그래밍을 위해 nVIDIA 사에서 개발한 병렬 처리 프로그래밍 개발환경이다. 본 논문에서는 가상 객체들 간의 삼각형 충돌 검사 부분을 CUDA 를 이용해 병렬적으로 구현하였다. 삼각형 충돌 검사는 실시간 충돌 검사 시 주요 병목현상을 일으키는 부분이다. 하지만 CPU 와 GPU 간의 데이터 전송 지연 문제 때문에 기존의 오브젝트 스페이스상의 GPU 기반의 충돌 검사 방법으로는 이 병목현상을 해결하기 어려웠다. 그러나 데이터 전송 지연 문제를 크게 완화시킨 CUDA 를 이용해 데이터 전송에 소모되는 비용을 줄이고 또한 삼각형 충돌 검사를 병렬적으로 수행함으로써 가상 객체를 형성하는 삼각형 집합들의 충돌검사 알고리즘의 성능을 크게 향상시킬 수 있었다.

• 가정과삶의질연구
• /
• 제26권1호
• /
• pp.107-120
• /
• 2008

The purpose of this study was to analyze the effects of human resource development on the job satisfaction and wage among employed workers. A sample of 3,578 employed workers was selected from Korea Labor Panel Data. For data analysis, t-test and multiple regression were used. The major findings were as follows: First, the employed workers who had experiences of human resource development had more certificates of job-related qualification, more employed in government-invested organization or foreign company regularly than the counterpart. Second, the employed workers' wage was affected by gender, age, educational attainment, as well as whether they had experiences of human resource development. Third, the factors that influence employed workers' job satisfaction were gender, age, educational attainment, job regularity, having certificate of job-related qualification or not, and having experiences of human resource development or not. From the findings, it can be concluded that the employed workers' wage and job satisfaction were improved by the human resource development.

• 천문학회보
• /
• 제42권2호
• /
• pp.49.3-50
• /
• 2017

There have been recent studies which revealed a tendency that thermal inertia decreases with the size of asteroidal bodies, and suggestions that thermal inertias of cometary bodies should be much smaller than those asteroidal counterparts, regardless of comets' nuclear sizes, which hints a way to differentiate cometary candidates from asteroids using thermal inertia information. We thus selected two comet-like objects from AKARI satellite of JAXA, namely, 107P/ (4015) Wilson-Harrington and P/2006 HR30 (Siding Spring), and applied simple thermophysical model to test the idea. Both targets did not show any comet-like activity during the observations. From the model, we found Wilson-Harrington to have size of 3.7-4.4 km, geometric albedo 0.040-0.055 and thermal inertia of 100-250 J m-2 K-1 s-0.5, which coincide with previous works, and HR30 to have size of 24-27 km, geomoetric albedo of 0.035-0.045 with thermal inertia of 250-1000 J m-2 K-1 s-0.5. HR30 is found to have the rotation pole near the ecliptic plane (the latitude between -20 and +60 deg). Based on the results, we conjecture that comet-like objects are not clearly distinguishable from asteroidal counterpart using thermal inertia.

• Journal of Mechanical Science and Technology
• /
• 제17권1호
• /
• pp.129-138
• /
• 2003

A 1 : 20 laboratory scale test rig of a 200 MW tangentially fired boiler is built up with completely simulated structures such as platen heaters and burners. Iso-thermal turbulent flow in the boiler is mapped by 3-D PDA (Particle Dynamic Analyzer). The 3-D numerical models for the same case are proposed based on the solution of к-$\varepsilon$ model closed RANS (Reynolds time-Averaged Navier-Stokes) equations, which are written in the framework of general coordinates and discretized in the corresponding body-fitted meshes. Not only are the grid lines arranged to fit the inner/outer boundaries. but also to align with the streamlines to the best possibility in order to reduce the NDE (numerical diffusion errors). Extensive comparisons of profiles of mean velocities are carried out between experiment and calculation. Predicted velocities in burner region were quantitatively similar with measured ones, while those in other area have same tendency with experimental counterpart.

• 소성∙가공
• /
• 제25권2호
• /
• pp.96-101
• /
• 2016

The current study was conducted to elucidate the effect of cementite morphology and matrix-ferrite microstructure on sliding wear behavior in spheroidized high carbon (1wt. % C) steel. The high carbon steel was initially heat treated to obtain a full pearlite or a martensite microstructure before the spheroidization. The spheroidizing heat treatment was performed on the full pearlitic steel for 100 hours at 700℃ and tempering was performed on the martensitic steel for 3 hours at 650℃. A spheroidized cementite phase in a ferrite matrix was obtained for both the full pearlite and the martensite microstructures. Sliding wear tests were conducted using a pin-on-disk wear tester with the heat treated steel as the disk specimen. An alumina(Al₂O₃) ball was used as the pin counterpart during the test. After the spheroidizing heat treatment and the tempering, both pearlite and martensite exhibited similar microstructures of spheroidized cementite in a ferrite matrix. The spheroidized pearlite specimens had lower hardness than the tempered martensite; however, the wear resistance of the spheroidized pearlite was superior to that of the tempered martensite.

• 천문학회보
• /
• 제36권2호
• /
• pp.81.2-81.2
• /
• 2011

Motivated by recent attempts to derive geomagnetic activity from hourly mean data in long term studies, we test the recursive Kalman filter method to obtain the regular solar variation curve of the geomagnetic field. Using a simple algorithm, we are able to assign a quiet day curve to every day separately, without the need for additional input parameter(s) to define the geomagnetically quiet days. We derive a digital counterpart AhK of the analog range index Ak at the subauroral Sodankyl$\ddot{a}$ station and compare it to the earlier digital estimate Ah and the local Ak index. We find that the new method outperforms the former estimate in every aspect studied and provides a robust, straightforward manner of estimating and verifying the manually scaled Ak index, based on readily available hourly values. The model is independent of sampling; thus, for shorter term studies where high-sampling data are available, more accurate estimates can also be obtained when needed. Therefore, in contrast to other recent approaches, we do not provide a method to quantify irregular activity directly but derive the actual quiet day curves in the traditional manner. In future applications the same algorithm may be used to define a wide variety of geomagnetic indices (such as Ak, Dst, or AE).

• 소성∙가공
• /
• 제13권8호
• /
• pp.716-722
• /
• 2004

Effects of sliding speed, applied load, and thickness of PMMA (Poly Methyl Methacrylate) coating layers on their dry sliding frictional and wear behavior were investigated. Sliding wear tests were carried out using a pin-on-disk wear tester. The PMMA layer was coated on Si wafer by a spin coating process with two different thicknesses, $1.5\mu\textrm{m}$ and $0.8\mu\textrm{m}$. AISI 52100 bearing steel balls were used as a counterpart of the PMMA coating during the wear. Normal applied load and sliding speed were varied. Wear mechanisms of the coatings were investigated by examining worn surfaces using an SEM. Friction coefficient of the coatings decreased with the increase of the applied load. Both adhesion and deformation of the coating determined the coefficient. The thicker PMMA layer with the thickness of $1.5mutextrm{m}$ showed lower friction coefficient than the thinner layer under most test conditions. Effects of sliding speed and applied load on the frictional behavior were varied depending on the thickness of the coating layer.

• 대한치과교정학회지
• /
• 제15권1호
• /
• pp.85-92
• /
• 1985

This investigation was designed to compare the craniofacial morphology of Class III malocclusions with that of normal occlusions using PM line. The subjects consisted of forty-four normal occlusions (twenty-three males and twenty-one females) and sixty-nine Class III malocclusions (thirty males and thirty-nine females), aged eight through ten. Using the tracings of the standard lateral cephalograms, various angles, linear measurements and linear ratios of counter-part were recorded and analyzed by t-test. The following characteristics of craniofacial morphology of Class III malocclusion were obtained by this study. 1. Maxillary anteroposterior position was balanced with Nasion but was not balanced with mandible because maxillary bony arch was small and positioned posteriorly and mandibular corpus was large and positioned relatively anteriorly. 2. Upper and lover alveolar bony arch were not balanced each other in its size. 3. In counterpart analysis, Class III malocclusion was more horizontally unbalanced than normal occlusion. 4. Class III malocclusion was divided into 11 groups by maxillary and mandibular bony arch position, size and alveolar bony arch size. Unbalanced bony size of the maxilla and mandible was a major characteristics of Class III malocclusion.

• 보건교육건강증진학회지
• /
• 제32권5호
• /
• pp.73-81
• /
• 2015

Objectives: We tried to confirm physical activity of 1,000 Kcal per week was a meaningful point in controlling coronary artery disease risks in female older adults. Methods: Participants were 66 female older adults recruited from senior welfare center. Participants were provided with accelerometer (e-step, Kenz, Japan) for measuring daily energy expenditure. Graded exercise test was done for measuring aerobic fitness. Blood glucose and lipid were analyzed. Framingham risk score was calculated based on blood glucose, blood lipid, and smoking. These variables were compared between the group expended more than 1,000 Kcal/week and the group with energy expenditure below 1,000 Kcal/week. Results: The group expended over 1,000kcal/week showed to be superior to the counterpart group in following variables; AC(Abdominal Circumference), %BF, $HR_{rest}$(resting heart rate), $VO_{2peak}$, FBG, LDL-C, TG, BDI-II, QOL, AR(Absolute Risk), RR(Relative Risk). Conclusions: The group expended over 1,000 Kcal/week was likely to have less probability in CAD than group expended less than 1,000 Kcal/week. The result of this study suggests the important role of active daily life that can be replaced with that of regular exercise especially for those who are not available to do structured exercise.

• Asian Journal of Business Environment
• /
• 제10권3호
• /
• pp.35-42
• /
• 2020

Purpose: Islamic banking products and services have always claimed to be unique from its traditional interest-based counterpart. However, in practice, many Islamic banks are alleged to have drifted away from its paradigm version. The purpose of this study is to gauge the perception of university students in Malaysia towards Islamic banking products. Research design, data and methodology: Data were collected from 250 Malaysian university students. Structural Equation Modeling (SEM) was performed to test proposed hypotheses to identify factors influencing customers' perception toward Islamic banking products. Results: The main finding indicates that most of the respondents are familiar with Islamic banking products and consider Islamic banking products as useful as its conventional counterparts. The regression results show that respondents are less convinced of adherence to Shari'ah, efficiency and helpfulness of existing Islamic banks. Conclusions: This is a cue to the Islamic banks' stakeholders that they need to realign their practices in an ethically responsible way in accordance with Shari'ah if they wish to secure existing customers and attract potential ones. In a competitive banking environment, most banks provide efficient and readily available service; thus, focusing on this as a strategy hardly distinguishes an Islamic bank from an interest-based bank.