• 제목/요약/키워드: structural understanding

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fθ 공식을 활용한 텔레센트릭 렌즈 및 플라이아이 렌즈의 설계 (The Design of Telecentric Lenses and Fly-eye Lenses by Utilizing fθ Formula)

  • 임천석
    • 한국광학회지
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    • 제24권1호
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    • pp.9-16
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    • 2013
  • 본 논문에서는 근축광학적인 대수식(algegraic equations)과 설계경험적인 근사조건을 통해 텔레센트릭 렌즈를 구조적으로 이해할 수 있는 일반화된 관계식을 찾는다. 이 관계식은 $f{\theta}$ 공식으로 명명되고, 단매렌즈, 이중가우스렌즈, 쿠크(Cooke)의 삼중렌즈, 쿠크의 삼중렌즈와 이중가우스렌즈가 결합된 복합렌즈의 순서로 단계적으로 적용된다. 그리고 이 공식은 조명광학용으로 사용되는 단매의 플라이아이 렌즈와 집광렌즈, 2매의 플라이아이 렌즈와 집광렌즈에 대해서도 순차적으로 적용된다. 여기서, 집광렌즈는 텔레센트릭 렌즈와 광학적으로 동일한 속성을 가진다. 결론적으로, 본 논문에서 찾은 $f{\theta}$ 공식은 텔레센트릭 렌즈에 대한 구조적인 이해를 이끌어냄과 동시에 직관적인 방식의 설계에도 활용될 수 있음을 보여 준다.

Hot AC Anodising as a Cr(VI)-free Pre-treatment for Structural Bonding of Aluminium

  • Lapique, Fabrice;Bjorgum, Astrid;Johnsen, Bernt;Walmsley, John
    • 접착 및 계면
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    • 제4권2호
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    • pp.21-29
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    • 2003
  • Hot AC anodising has been evaluated us pre-treatment for aluminium prior to structural adhesive bonding. Phosphoric and sulphuric acid hot AC anodising showed very promising adhesion promoter capabilities with durability comparable with the best standard DC anodising procedures. AC anodising does not required etching prior to anodising and offers u pre-treatment time down to 20 seconds. The interface/interphase between the aluminium substrate and the adhesive was investigated in order to get a better understanding of the involved adhesion mechanisms and to explain the long-tenn properties. The alkaline medium formed at the oxide layer/adhesive interface has been shown to induce a partial dissolution of the oxide layer leading to the formation of metallic ions which diffuse in the adhesive (EPMA measurements). The effect of diffusion of the Al ions on adhesion and joint durability is still uncertain but studies showed that pre-bond moisture affected the joints durability and to some extent the diffusion length. specially for DC anodised samples. So far no direct correlation could be established between the diffusion length d and the joints durability but new trials with better control over the elapsed time between bonding and adhesive curing are expected to help getting a better understanding of the involved mechanisms.

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Impact of glycosylation on the unimpaired functions of the sperm

  • Cheon, Yong-Pil;Kim, Chung-Hoon
    • Clinical and Experimental Reproductive Medicine
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    • 제42권3호
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    • pp.77-85
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    • 2015
  • One of the key factors of early development is the specification of competence between the oocyte and the sperm, which occurs during gametogenesis. However, the starting point, growth, and maturation for acquiring competence during spermatogenesis and oogenesis in mammals are very different. Spermatogenesis includes spermiogenesis, but such a metamorphosis is not observed during oogenesis. Glycosylation, a ubiquitous modification, is a preliminary requisite for distribution of the structural and functional components of spermatids for metamorphosis. In addition, glycosylation using epididymal or female genital secretory glycans is an important process for the sperm maturation, the acquisition of the potential for fertilization, and the acceleration of early embryo development. However, nonemzymatic unexpected covalent bonding of a carbohydrate and malglycosylation can result in falling fertility rates as shown in the diabetic male. So far, glycosylation during spermatogenesis and the dynamics of the plasma membrane in the process of capacitation and fertilization have been evaluated, and a powerful role of glycosylation in spermatogenesis and early development is also suggested by structural bioinformatics, functional genomics, and functional proteomics. Further understanding of glycosylation is needed to provide a better understanding of fertilization and embryo development and for the development of new diagnostic and therapeutic tools for infertility.

육류에 대한 혐오감이 돼지고기 소비에 미치는 인과 효과 평가 (Measuring the Causal Effect of Disgust with Meat on Pork Consumption)

  • 강종헌;배성식
    • 동아시아식생활학회지
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    • 제17권5호
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    • pp.653-660
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    • 2007
  • The purpose of this study was to measure the causal relationships among such variables as moral concerns for animals, meat texture, meat color, satiety from meat, disgust with meat and pork consumption. A total of 250 questionnaires were completed. Structural equation models were used to measure the causal effects of the constructs. The study outcomes demonstrated that the structural analysis results of the data were an excellent model fit. The effects of moral concerns for animals, meat texture and satiety from meat on the disgust with meat were statistically significant. As expected, disgust with meat had a significant effect on pork consumption. Moreover, moral concerns for animals and satiety from meat had a significant indirect effect on pork consumption through disgust with meat. Also, satiety from meat alone had a significant indirect effect on pork consumption through disgust with meat. By developing and testing conceptual models that integrated the relationships among ideational variables, sensory affective variables, anticipated consequences variables, emotional variables, and behavioral variables, this study may approach a deeper understanding of the complex relationships among pork consumption-related variables. A greater understanding of these complex relationships can improve the managerial diagnosis of problems as well as opportunities for different marketing strategies, including pork production and pork product development, and marketing communications.

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AEM on Growth Mechanism of Synthesized Graphene on Ni Catalyst

  • 박민호;이재욱;배지환;송관우;김태훈;양철웅
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.579-579
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    • 2012
  • Graphene has recently been a subject of much interest as a potential platform for future nanodevices such as flexible thin-film transistors, touch panels, and solar cells. And chemical vapor deposition (CVD) and related surface segregation techniques are a potentially scalable approach to synthesizing graphite films on a variety of metal substrates. The structural properties of such films have been studied by a number of methods, including Raman scattering, x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). An understanding of the structural quality and thickness of the graphite films is of paramount importance both in improving growth procedures and understanding the resulting films' electronic properties. In this study, we synthesized the few-layered grapheneunder optimized condition to figure out the growth mechanism seen in CVD-grown graphenee by using various electron microscope. Especially, we observed directly film thickness, quality, nucleation site, and uniformity of grpahene by using AEM. The details will be discussed in my presentation.

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27Al Solid-state NMR Structural Studies of Hydrotalcite Compounds Calcined at Different Temperatures

  • Park, Tae-Joon;Choi, Sung-Sub;Kim, Yong-Ae
    • Bulletin of the Korean Chemical Society
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    • 제30권1호
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    • pp.149-152
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    • 2009
  • Hydrotalcites are anionic clays that are quite prevalent in nature and their importance is growing more and more because of their very wide range of potential applications and uses. Understanding the structural and compositional changes that occur on the molecular scale during the thermal decomposition of hydrotalcite compounds is essential for the basic prediction and comprehensive understanding of the behavior and technical application of these materials. In this study, several hydrotalcite compounds calcined at different temperatures for applications in a chlorine resistant textile were prepared and 27-Aluminm solid-state nuclear magnetic resonance (NMR) spectroscopy was used as a tool to study their local structure and behavior. The changes in the Al coordination of the hydrotalcite compounds were investigated with one dimensional (1D) solid-state magic angle spinning (MAS) NMR spectroscopy. The two broad resonances arising from the structurally different Al coordinations of these compounds were clearly resolved by two dimensional (2D) triple quantum magic angle spinning (3QMAS) NMR spectroscopy.

hpvPDB: An Online Proteome Reserve for Human Papillomavirus

  • Kumar, Satish;Jena, Lingaraja;Daf, Sangeeta;Mohod, Kanchan;Goyal, Peyush;Varma, Ashok K.
    • Genomics & Informatics
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    • 제11권4호
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    • pp.289-291
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    • 2013
  • Human papillomavirus (HPV) infection is the leading cause of cancer mortality among women worldwide. The molecular understanding of HPV proteins has significant connotation for understanding their intrusion in the host and designing novel protein vaccines and anti-viral agents, etc. Genomic, proteomic, structural, and disease-related information on HPV is available on the web; yet, with trivial annotations and more so, it is not well customized for data analysis, host-pathogen interaction, strain-disease association, drug designing, and sequence analysis, etc. We attempted to design an online reserve with comprehensive information on HPV for the end users desiring the same. The Human Papillomavirus Proteome Database (hpvPDB) domiciles proteomic and genomic information on 150 HPV strains sequenced to date. Simultaneous easy expandability and retrieval of the strain-specific data, with a provision for sequence analysis and exploration potential of predicted structures, and easy access for curation and annotation through a range of search options at one platform are a few of its important features. Affluent information in this reserve could be of help for researchers involved in structural virology, cancer research, drug discovery, and vaccine design.

육류에 대한 태도와 소비행동에 영향을 미치는 요인들의 인과관계 평가 (Measuring the Causal Relationship among Factors Influencing Attitude toward Meat and Consumption Behavior)

  • 강종헌;정항진
    • 한국식생활문화학회지
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    • 제23권3호
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    • pp.328-335
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    • 2008
  • The objective of this study was to evaluate the causal relationships among environmental belief, ambivalence, subjective norm, attitude and meat consumption behavior. A total of 318 questionnaires were completed. A structural equation model was employed to assess the causal effects of constructs. The results of the study demonstrated that the structural analysis results for the data also indicated excellent model fit. The effects of environmental belief, ambivalence, and subjective norm on attitude were statistically significant. The effects of environmental belief, subjective norm and attitude on meat consumption were statistically significant. The effects of attitude on intention were statistically significant. As had been expected, intention exerted a significant effect on meat consumption. Moreover, environmental belief and ambivalence exerted significant indirect effects on meat consumption through attitude. Subjective norm exerted a significant indirect effect on meat consumption through attitude and intention. Subjective norm also exerted a significant indirect effect on intention through attitude. In developing and testing conceptual models which integrate the relationship among behavioral belief, attitude variable, behavioral intention and meat consumption, this study may approach a deeper understanding of the complex relationship among meat consumption behavior-related variables. Greater understanding of the complex relationship among meat consumption behavior-related variables can improve the practical or managerial diagnosis of the problem and opportunities for different marketing strategies including meat production and meat product development and marketing communication.

Factors Reducing Credit Card's Perceived Risk in Retail Payment: An Approach to Consumer Traits

  • Nam Hoang TRINH;Hong Ha TRAN
    • 유통과학연구
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    • 제21권11호
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    • pp.67-75
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    • 2023
  • Purpose: The study is focused on understanding consumer behaviour related to credit card use in retail payment or identifying factors that influence risk perception. Research design, data and methodology: Based on data collecting from structured self-administered questionnaires of 247 Vietnamese bank account payers, this study uses the Cronbach alpha analysis, the factor analyses, the structural equation modeling to assess the research's measurement model and structural model with the presence of knowledge, propensity to trust, self-efficacy, risk perception, intended use and their complex, intertwined relationships. Results: The results reveal that customer's perceived risk, which is affected by their self-efficacy and propensity to trust, negatively impact on their intended use of credit cards in retail payment. However, there is no evidence of the significant influence of consumer knowledge on how they assess potential losses of credit card. Conclusions: These findings provide a better understanding of consumer risk perception, its antecedents and consequence in a direction of credit card adoption. Bank managers or marketers should focus on increasing the information about credit cards and issues related to credit card use in retail payment, promoting mechanisms to encourage customers to participate in the credit card experience.

Structural Aspects of GPCR-G Protein Coupling

  • Chung, Ka Young
    • Toxicological Research
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    • 제29권3호
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    • pp.149-155
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    • 2013
  • G protein-coupled receptors (GPCRs) are membrane receptors; approximately 40% of drugs on the market target GPCRs. A precise understanding of the activation mechanism of GPCRs would facilitate the development of more effective and less toxic drugs. Heterotrimeric G proteins are important molecular switches in GPCR-mediated signal transduction. An agonist-activated receptor interacts with specific sites on G proteins and promotes the release of GDP from the $G{\alpha}$ subunit. Because of the important biological role of the GPCR-G protein coupling, conformational changes in the G protein upon receptor coupling have been of great interest. One of the most important questions was the interface between the GPCR and G proteins and the structural mechanism of GPCR-induced G protein activation. A number of biochemical and biophysical studies have been performed since the late 80s to address these questions; there was a significant breakthrough in 2011 when the crystal structure of a GPCR-G protein complex was solved. This review discusses the structural aspects of GPCR-G protein coupling by comparing the results of previous biochemical and biophysical studies to the GPCR-G protein crystal structure.