• The Korean Journal of Rheology
• /
• v.8 no.2
• /
• pp.78-91
• /
• 1996

단섬유 보강 플라스틱 복합재료에 사출성형에서 섬유배향은 금형 충전 공정 중의 유동장에 의해 결정되고 섬유의 배향 상태는 역으로 유동장에 영향을 미친다. 단섬유에 의 한 추가적인 응력을 포함하는 Dinh과 Armstrong의 이방성 구성방정식을 충전유동과 섬유 배향의 연계해석에 도입하였다. 충전유동의 해석은 새로운 압력 지배방정식과 에너지 방정 식을 유한요소법과 유한차분법을 이용하여 풀고 동시에 2차 배향 텐서의 변화방정식을 4차 Runge-kutta 방법으로 풀었다. 섬유의 배향상태를 구한 후에 일방향성 복합재료의 Halpin-Tsai 식과 배향 평균모델을 도입하여 사풀성형품의 이방성 기계적 성질이 예측되었 다. 직사각형 캐비티에서 수치해석결과를 실험결과와 비교하였다. 섬유배향과 유동과의 상호 연계작용을 특히 게이트 근처에서 섬유배향에 영향을 미치며 수치해석 결과는 벽면 근처에 서 유동방향으로 배향하는 shell층을 과대 예측함을 알수 있었는데 이는 배향 텐서 변화 방 정식의 최종근사에서 기인하는 오차로 판단된다. 수정된 복합최종 근사를 바탕으로 예측된 이방성 기계적 성질이 기존의 복합최종 근사에 기초한 예측보다 실험 결과에 정량적으로 보 다 잘 일치하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.4
• /
• pp.306-313
• /
• 1998

To elucidate the liquid crystal(LC) molecules alignment mechanism, it is important to determine the molecular orientation of the rubbed polymer surface molecules that directly contact with LC molecules. In this work, the molecular orientation on a rubbed surface of polyimide (SE-3310, Nissan) film has been studied by polarized FTIR absorption spectroscopy. It has been found that molecular chain on the rubbed surface of polymide film are oriented along the rubbing direction and are tilted up on an average by 5.0$^{\circ}$. In the SHG(Second Harmonic Generation) measurement, the pretilt angle of molecular chain on the poylmide fim was 4.6$^{\circ}$ fro, the surface plane. And the pedit angle of liquid crystal (ZLI-2293, Merck) molecules measured by crystal rotation method was 5.4$^{\circ}$in the same rubbing condition.

• Journal of Biomedical Engineering Research
• /
• v.32 no.2
• /
• pp.118-126
• /
• 2011

This study proposes a human body orientation tracking system by inertial and earth magnetic sensors. These sensors were fused by indirect Kalman filter. The proposed tracking system was configured and the filter was implemented. The tracking performance was evaluated with static and dynamic tests. In static test, the sensor was fixed on the floor while its static characteristics was analyzed. In dynamic test, the sensor was held and moved manually for 30 seconds. The dynamic test included x, y, z axis rotations, and elbow flection/extension motions that mimic drinking. For these dynamic motions, the tracking angle error was under $4.1^{\circ}$ on average. The proposed tracking method is expected to be useful for various human body motion analysis.

• Bulletin of the Korean Chemical Society
• /
• v.7 no.2
• /
• pp.124-129
• /
• 1986

The effects of molecular attraction and orientations for the energy mismatch variance, vibrational energy level and double-quantum transition, in the vibration-vibration energy exchange, have been considered. The contribution of molecular attraction increases the exchange rate of the purely repulsive interaction, in general, significantly, but which becomes smaller as the temperature is increased. As the energy mismatch is increased, its contribution is also increased, but which is small. However, its contribution for the double-quantum transition is very paramount. At each orientation, the exchange rate constants have been calculated and compared with the results for rotational average, and it is found that the exchange rate is a strong function of the orientation angles of colliding molecules. We have also discussed about the system having the strong interaction such as the hydrogen bond, and it is found that for this system the preferred orientation should be considered in order to calculate the exchange rates.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.36 no.2
• /
• pp.152-164
• /
• 2012

This study develops a valid and reliable scale to evaluate customer orientation for clothing salespeople in order to provide a foundation for systematic and empirical research in the apparel industry. The study was conducted in two phases. First, a scale was developed to evaluate the customer orientation of clothing salespeople through a qualitative method. The second phase involved the verification of the validity of the developed evaluation questions through a quantitative method. The subjects of this study were 327 clothing salespeople, and the results were analyzed using AMOS 7.0 and SPSS 15.0. The results were as follows: First, customer orientation questions were elicited from in-depth interviews with fashion sales-people, analyses of fashion magazine articles, and previous studies. From the results, 38 preliminary questions were selected based on categorization, modification, and expert analyses of the content validity. Second, in order to verify the validity of the customer orientation scale that consisted of 24 questions in 7 factors, we performed a verification of the convergent validity through an assessment of the magnitude of standardization factor loading, average variance extracted (AVE), and construct reliability. Discriminant validity was verified using the AVE of each of the two constructs and a comparison of the square of the correlation between the constructs. According to the results, the measured values were above or near the guideline values that demonstrates the validity of the customer orientation scale.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.41 no.8
• /
• pp.783-789
• /
• 2017

In terms of 3D orientation estimation based on nine-axis IMMU(inertial and magnetic measurement unit), there are two disturbance components decreasing estimation accuracy: one is external acceleration disturbing accelerometer's signals and the other is magnetic disturbance related to magnetometer's signals. In order to minimize effects by these two disturbances, two approaches including switching approach and model-based approach have been suggested and further research comparing these two has also been conducted. Nevertheless, effect of disturbance modeling differences on orientation estimation accuracy in model-based approach has not been studied before. This paper compares the recently reported two orientation estimation algorithms that have difference in disturbance models, in order to investigate the effect of disturbance models on accuracy of IMMU-based orientation estimation under various operating conditions. This research shows that the difference in disturbance models leads to difference in process noise covariance matrix. Consequently, this affected the orientation estimation, i.e., the estimation differences between the algorithms were root mean square errors of $1.35^{\circ}$ in average and $3.63^{\circ}$ in yaw estimation.

• Journal of the Korean Home Economics Association
• /
• v.36 no.11
• /
• pp.119-128
• /
• 1998

This study was designed to find tendencies of housing value orientation of the model steel house visitors. Questionnaires were collected in June, 1997, 1,550 in total, 508 cases from Seoul, 456 cases from Pohang, and 486 cases from Kwangyang. Data were analyzed in terms of housing value orientation, using statistical methods including frequencies, mean, percentages, chi-square test and multiple regression. The major findings are as follows; 1. The subjects were highly educated(64% of them were college graduates) with the monthly income over 2,000,000won(approximately $1,540). The average monthy income of the subjects in Seoul, about 4,000,000won($3,070), was much higher than that of other areas. Most of the subjects were condominium owners(72%), who preferred single detatched houses or town houses located in suburban areas. 2. Differences in general tendencies among the three regional groups were statistically significant. Most significantly, subjects living in Pohang regarded the reputation of the building construction company most importnat. Subjects of all three regional areas, especially in Pohang, emphasized investment value. The price of the steel house was regarded as very important by all the groups tested. The housing value orientation was analyzed in 3 aspects; (1) Facility.Plumbing.Structure(FPS), (2) Interior space formation.Design(ID) and (3) Developmental complex.Near Environment(DN). Interior environment level, stability of house structure, and finighing state of interiors were identified as the important factors in the area of FPS(p<.05). The Interior plan organization was the most important factor among ID. As for DN, rated importantly were educational facilities, green areas, convenience of commercial facilities within the developmental complex were rated importantly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.192-193
• /
• 2006

A 16Mb ITIC FeRAM device was fabricated with BLT capacitors. The average value of the switchable 2 polarization obtained m the 32k-array (unit capacitor size: 068 ${mu}m^2$) capacitors was about 16 ${\mu}C/cm^2$ at 3V and the uniformity within an 8-inch wafer was about 2.8%. But a lot of cells were failed randomly during the measuring the bit-line signal of each cell. It was revealed that the Grain size and orientation of the BLT thin film were severely non-uniform. Therefore, the uniformity of the grain size and orientation was improved by changing the process conditions of post heat treatment. The temperature of nucleation step was the very effective on varying the microstructure of the BLT thin film. The optimized temperature of the nucleation step was $560^{\circ}C$.

• The Research Journal of the Costume Culture
• /
• v.18 no.5
• /
• pp.1048-1061
• /
• 2010

The purpose of the study was to compare the culture and the clothing value between Korean and American college students, especially men. Also, this study was to analyze the culture effect on the clothing value. The survey was performed and 200 questionnaires were utilized for this study. The SPSS 12.0 was used to analyze the technical statistics like average, frequency, t-test, factor analysis, multiple regression analysis. The result showed, first, there were some 2 major cultural differences such as power distance and long-term orientation between Korean and American college men. Comparatively, Korean college men showed higher masculinity and lower power distance and long-term orientation. Second, there were differences in the clothing value aspect. Both of them considered the economic clothing value to be most important. Third, there were some differences in the clothing value because of the cultural differences. For Korean college men, there were masculinity and long term orientation that had an effect on the social and religious clothing values, however, for American college men, power distance, masculinity and long term orientation that had an effect on the social, religious, theoretical and economic values.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.15 no.4
• /
• pp.502-506
• /
• 2012

In order to find the structural characteristics of the thin films of group II-VI semiconductor compounds compared with those of powder materials, films were made of 4 powders of ZnS, CdS, CdSe, and CdTe(Aldrich), each with 99.99 % purity. For the ZnS/CdS multi-layers, the ZnS layer was coated over the CdS layer on an $AlO_x$ membrane, which served as a protective layer within a vacuum at the average speed of 1 ${\AA}$/sec. After studying the structures of the group II-VI semiconductor thin films by using X-ray spectroscopy, we found that the ZnS, ZnS/CdS, CdS, and CdSe films were hexagonal and exhibited some degree of preferred orientation. Also, the particles of the thin films of II-VI semiconductor compounds proved to be more homogeneous in size compared to those of the powder materials. These results were further verified through scanning electron microscopy(SEM), EDX analysis, and powder and thin film X-ray diffraction.