• Title/Summary/Keyword: theoretical analyses

Search Result 838, Processing Time 0.026 seconds

A Study for properties of Renderers to 3D Rendering education (3D 렌더링 교육을 위한 렌더러 특성 연구 (Arnold, V-ray, Octane, Redshift를 중심으로))

  • Cho, Hyung-ik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.05a
    • /
    • pp.293-295
    • /
    • 2018
  • The final stage of the 3D work is rendering. After all, all 3D works are looking at via this rendered result, so the importance of the Rendering cannot be overstated. Because this is the final stage of 3D work, it requires a lot of theoretical and functional training in rendering control. However, However, it is difficult to invest as much time in college education in a limited period. This paper will compare and analyze the characteristics, and merits and demerits of these various kinds of Renderer (MARI, QUIXEL, Substace designer), and showed the result of analyses about the fact that educating which of the above 4 Renderers are helpful and beneficial for the students for the efficient education in the university where should teach much in the limited time.

  • PDF

An Atomistic Modeling for Electromechanical Nanotube Memory Study (원자단위 Electromechanical 모델링을 통한 나노튜브 메모리 연구)

  • Lee, Kang-Whan;Kwon, Oh-Keun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.19 no.2
    • /
    • pp.116-125
    • /
    • 2006
  • We have presented a nanoelectromechanical (NEM) model based on atomistic simulations. Our models were applied to a NEM device as called a nanotube random access memory (NRAM) operated by an atomistic capacitive model including a tunneling current model. We have performed both static and dynamic analyses of a NRAM device. The turn-on voltage obtained from molecular dynamics simulations was less than the half of the turn-on voltage obtained from the static simulation. Since the suspended carbon nanotube (CNT) oscillated with the amplitude for the oscillation center under an externally applied force, the quantity of the CNT-gold interaction in the static analysis was different from that in the dynamic analysis. When the gate bias was applied, the oscillation centers obtained from the static analysis were different from those obtained from the dynamics analysis. Therefore, for the range of the potential difference that the CNT-gold interaction effects in the static analysis were negligible, the vibrations of the CNT in the dynamics analysis significantly affected the CNT-gold interaction energy and the turn-on voltage. The turn-on voltage and the tunneling resistance obtained from our tunneling current model were in good agreement with previous experimental and theoretical works.

A Prediction Model for Internet Game Addiction in Adolescents: Using a Decision Tree Analysis (의사결정나무 분석기법을 이용한 청소년의 인터넷게임 중독 영향 요인 예측 모형 구축)

  • Kim, Ki-Sook;Kim, Kyung-Hee
    • Journal of Korean Academy of Nursing
    • /
    • v.40 no.3
    • /
    • pp.378-388
    • /
    • 2010
  • Purpose: This study was designed to build a theoretical frame to provide practical help to prevent and manage adolescent internet game addiction by developing a prediction model through a comprehensive analysis of related factors. Methods: The participants were 1,318 students studying in elementary, middle, and high schools in Seoul and Gyeonggi Province, Korea. Collected data were analyzed using the SPSS program. Decision Tree Analysis using the Clementine program was applied to build an optimum and significant prediction model to predict internet game addiction related to various factors, especially parent related factors. Results: From the data analyses, the prediction model for factors related to internet game addiction presented with 5 pathways. Causative factors included gender, type of school, siblings, economic status, religion, time spent alone, gaming place, payment to Internet cafe$\acute{e}$, frequency, duration, parent's ability to use internet, occupation (mother), trust (father), expectations regarding adolescent's study (mother), supervising (both parents), rearing attitude (both parents). Conclusion: The results suggest preventive and managerial nursing programs for specific groups by path. Use of this predictive model can expand the role of school nurses, not only in counseling addicted adolescents but also, in developing and carrying out programs with parents and approaching adolescents individually through databases and computer programming.

Study on Internal Service Quality, Job Satisfaction and Customer Satisfaction in Airline Industry

  • Kim, Seung-Lee;Cho, Young-Shin
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.3
    • /
    • pp.113-121
    • /
    • 2016
  • In this study, the basic concept of service profit chain was introduced based on the existing studies related to service quality of airline ground crew to find out how are customer satisfaction influenced by factors related to employees who provide service quality to the customers, such as internal service quality and job satisfaction. The data of this study was collected by questionnaire and based on airline ground crews and Gimpo international airport users. A total of 190 of airline ground crew and 273 of passengers validity sample was analyzed a frequency analysis, reliability analysis, exploratory factor analysis and correlation coefficient analysis from SPSS 21, a hypothesis through out confirmatory factor analysis and structural equation modeling from AMOS 7.0. As a result of the analyses, it was found that the models was appropriate in proving the hypotheses on interrelationships among internal service quality, job satisfaction and customer satisfaction. Overall, finding of this study enhance the theoretical progress on the experiential concept in walking tour and offer important implication for airline industry marketers.

Theoretical Study of the Reaction Mechanism for SiF2 Radical with HNCO

  • Hou, Li-Jie;Wu, Bo-Wan;Kong, Chao;Han, Yan-Xia;Chen, Dong-Ping;Gao, Li-Guo
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.12
    • /
    • pp.3738-3742
    • /
    • 2013
  • The reaction mechanism of $SiF_2$ radical with HNCO has been investigated by the B3LYP method of density functional theory(DFT), while the geometries and harmonic vibration frequencies of reactants, intermediates, transition states and products have been calculated at the B3LYP/$6-311++G^{**}$ level. To obtain more precise energy result, stationary point energies were calculated at the CCSD(T)/$6-311++G^{**}$//B3LYP/$6-311++G^{**}$ level. $SiF_2+HNCO{\rightarrow}IM3{\rightarrow}TS5{\rightarrow}IM4{\rightarrow}TS6{\rightarrow}OSiF_2CNH(P3)$ was the main channel with low potential energy, $OSiF_2CNH$ was the main product. The analyses for the combining interaction between $SiF_2$ radical and HNCO with the atom-in-molecules theory (AIM) have been performed.

The Provider-Role Consciusness of Married Working Women (취업주부의 부양자역할의식에 관한연구)

  • 옥선화
    • Journal of Families and Better Life
    • /
    • v.11 no.1
    • /
    • pp.134-148
    • /
    • 1993
  • The study was designed to examine the present state of the provider-role consciousness of married working women in Korea and to identify five variable-clusters which were drawn from the theoretical perspectives. The subjects of this study were 573 married working women whose husbands also had their work. The statistical methods adopted for data analyses were frequencies. oneway ANOVA. Scheffe-test t-test, and multiple regression analysis. The major findings of this study can be summarized as follows; 1) The level of the provider-role consciousness of married working women was slightly high. 2) As for the aspects of the individual attribute variables. educational level job income age native area motive of work. and sex-role identity significantly influenced the provider-role consciousness of married working women. 3) Concerning the family background variables marriage duration number of children mother's experience of employment father's educational level and husbands's income were significantly related to the provider-role consciousness of married working women, 4) As for the social relationship variables. degree of participation in social associations significant others' attitudes toward housewife's work degree of domestic role sharing with husband and wife/husband income ration significantly affected the provider-role conscious-ness of married working women. Based on these findings it came to be revealed that multidirectional perspecitves were useful to identify variables which could predict the provider-role consciousness of married working women, Also it was revealed that the significant others' approvals for women's work were necessary to the establishment of the provider-role consciousness of married working women.

  • PDF

Electrostatic upper-hybrid waves and energetic electrons in the Earth's radiation belt

  • Hwang, Junga;Shin, Dae-Kyu;Yoon, Peter H.;Kurth, William S.;Lee, Dae-Young
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.41 no.2
    • /
    • pp.42.2-43
    • /
    • 2016
  • Electrostatic fluctuations near upper-hybrid frequency, which are sometimes accompanied by multiple-harmonic electron cyclotron frequency bands above and below the upper-hybrid frequency, are common occurrences in the Earth's radiation belt, as revealed through the twin Van Allen Probe spacecraft. In the literature upper-hybrid emissions are used for estimating the background electron density, which in turn can be used to determine the plasmapause locations, but the role of energetic electrons in generating such fluctuations has not been discussed. The present paper carries out detailed analyses of data from the Waves instrument, which is part of the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) suite onboard the Van Allen Probes. Combined with theoretical calculation, it is demonstrated that the peak intensity associated with the upper-hybrid fluctuations is predominantly determined by tenuous but energetic electrons, and that denser and less energetic background electrons do not contribute much to the peak intensity. This finding shows that upper-hybrid fluctuations detected during quiet time are useful not only for the determination of the electron density, but also they contain information on the ambient energetic electron population as well.

  • PDF

A Study on LLC Resonant Converter Employing Coupled Inductor to Reduce Output Current Ripple (커플드 인덕터를 활용하여 출력 전류 리플을 저감하는 LLC 공진형 컨버터에 관한 연구)

  • Lee, Yong-Chul;Kang, Min-Hyuck;Kang, Chan-Ho;Hong, Sung-Soo
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.23 no.3
    • /
    • pp.208-216
    • /
    • 2018
  • In this paper, an LLC resonant converter employing two coupled inductors on the secondary side of the converter is proposed. The conventional LLC converter exhibits serious power loss during secondary winding of the transformer because of generation of tremendous output current ripples. To overcome this problem, an LLC resonant converter with a current doubler as a rectifying circuit was recently proposed. However, the current-doubler rectifying circuit requires coupled inductors with a high coupling ratio to retain the designed resonance characteristics. Therefore, an additional hardware filter is required at the output stage to address large output current ripples. Additional design procedures are also necessary because the inductance component of the added filter affects the designed resonant network. To solve this issue, an LLC resonant converter employing two coupled inductors is proposed in this paper. Mathematical analysis shows that the proposed secondary-side current-doubler circuit does not affect the designed resonance characteristics. The operating principles and theoretical analyses are proven through a simulation and experiments with a 54 V/28 A prototype.

An Estimation on the Applicability of Hollow FRP Soil Nailing System (중공식 FRP쏘일네일링 시스템의 적용성 평가)

  • Kim, Hong-Taek;Lee, Hyuk-Jin;Jung, Woo-Chul;Koh, Hyung-Seon
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.03a
    • /
    • pp.1014-1023
    • /
    • 2006
  • Soil nailing is a reinforcement method used for stabilizing excavated wall or slope. Due to its many advantages such as ease of construction and economical efficiency, use of soil nailing is increased. However, the soil nail can't trespass on the neighbor private land, which pays rent for use. For this reason, removable soil nailing system was developed. However, the removal rate of this system is just about $50\sim70%$. To solve this, the Fiber Reinforced Polymer (FRP) soil nailing system, which does not need to be removed and allows for the trespass on the private land, is developed. In this paper, through theoretical and experimental studies in laboratory and field, we evaluate the stability and behavior characteristics of the FRP nail system. Besides, numerical analyses using FLAC2D were performed for various soil conditions, where the simulations for pullout tests were carried out. As a result, compared with the conventional removable soil nailing system, the FRP soil nailing systems show similar behavior characteristics.

  • PDF

A Study on the Stiffness Locking Phenomena and Eigen Problem in a Curved Beam (곡선보의 강선 과잉 현상과 고유치에 관한 연구)

  • 민옥기;김용우;유동규
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.14 no.2
    • /
    • pp.310-323
    • /
    • 1990
  • A three-noded, with three degree-of-freedom at each node, in-plane curved beam element is formulated and employed in eigen-analysis of constant curvature beam. The conventional quadratic shape functions used in a three noded C .deg. type curved beam element produce such an undesirable large stiffness that a significant error is introduced in displacements and stresses. These phenomena are called 'Stiffness Locking Phenomena', which result from spurious strain energy due to inappropriate assumptions on independent isoparametric quadratic interpolation functions. Stiffness locking phenomena can be alleviated by using modified interpolation functions which get rid of spurious constraints of conventional interpolation functions. Eigenvalues and their modes as well as displacements and stresses may be locked because they are related to stiffness. Using modified curved beam element in eigenvalue problem of cantilever and arch, the property and performance of modified curved beam element are examined by numerical experimentations. In these eigen-analyses, mass matrices are calculated by using both modified and unmodified curved beam element, are compared with theoretical solutions. These comparisons show that the performance of the modified curved beam element is better than that of the unmodified curved beam element.