• Title/Summary/Keyword: Internal reflection

Search Result 240, Processing Time 0.032 seconds

Evaluation of the Photon Transmission Efficiency of Light Guides Used in Scintillation Detectors Using LightTools Code

  • Park, HyeMin;Joo, Koan Sik;Kim, Jeong Ho;Kim, Dong Sung;Park, Ki Hyun;Park, Chan Jong;Han, Woo Jun
    • Journal of Radiation Protection and Research
    • /
    • v.41 no.3
    • /
    • pp.282-285
    • /
    • 2016
  • Background: To optimize the photon transmission efficiency of light guides used in scintillation detectors, LightTools code, which can construct and track light, was used to analyze photon transmission effectiveness with respect to light guides thickness. Materials and Methods: This analysis was carried out using the commercial light guide, N-BK 7 Optical Glass by SCHOTT, as a model for this study. The luminous exitance characteristic of the LYSO scintillator was used to analyze the photon transmission effectiveness according to the thickness of the light guide. Results and Discussion: The results of the simulations showed the effectiveness of the photon transmission according to the thickness of the light guide, which was found to be distributed from 13.38% to 33.57%. In addition, the photon transmission efficiency was found to be the highest for light guides of 4 mm of thickness and a receiving angle of $49^{\circ}$. Conclusion: Through such simulations, it is confirmed that photon transmission efficiency depends on light guide thickness and subsequent changes in the internal angle of reflection. The aim is to produce an actual light guide based on these results and to evaluate its performance.

Single-Protein Molecular Interactions on Polymer-Modified Glass Substrates for Nanoarray Chip Application Using Dual-Color TIRFM

  • Kim, Dae-Kwang;Lee, Hee-Gu;Jung, Hyung-Il;Kang, Seong-Ho
    • Bulletin of the Korean Chemical Society
    • /
    • v.28 no.5
    • /
    • pp.783-790
    • /
    • 2007
  • The immobilization of proteins and their molecular interactions on various polymer-modified glass substrates [i.e. 3-aminopropyltriethoxysilane (APTS), 3-glycidoxypropyltrimethoxysilane (GPTS), poly (ethylene glycol) diacrylate (PEG-DA), chitosan (CHI), glutaraldehyde (GA), 3-(trichlorosilyl)propyl methacrylate (TPM), 3'-mercaptopropyltrimethoxysilane (MPTMS), glycidyl methacrylate (GMA) and poly-l-lysine (PL).] for potential applications in a nanoarray protein chip at the single-molecule level was evaluated using prismtype dual-color total internal reflection fluorescence microscopy (dual-color TIRFM). A dual-color TIRF microscope, which contained two individual laser beams and a single high-sensitivity camera, was used for the rapid and simultaneous dual-color detection of the interactions and colocalization of different proteins labeled with different fluorescent dyes such as Alexa Fluor® 488, Qdot® 525 and Alexa Fluor® 633. Most of the polymer-modified glass substrates showed good stability and a relative high signal-to-noise (S/N) ratio over a 40-day period after making the substrates. The GPTS/CHI/GA-modified glass substrate showed a 13.5-56.3% higher relative S/N ratio than the other substrates. 1% Top-Block in 10 mM phosphate buffered saline (pH 7.4) showed a 99.2% increase in the blocking effect of non-specific adsorption. These results show that dual-color TIRFM is a powerful methodology for detecting proteins at the single-molecule level with potential applications in nanoarray chips or nano-biosensors.

Monitoring of a CFRP-Stiffened Panel Manufactured by VaRTM Using Fiber-Optic Sensors

  • Takeda, Shin-Ichi;Mizutani, Tadahito;Nishi, Takafumi;Uota, Naoki;Hirano, Yoshiyasu;Iwahori, Yutaka;Nagao, Yosuke;Takeda, Nobuo
    • Advanced Composite Materials
    • /
    • v.17 no.2
    • /
    • pp.125-137
    • /
    • 2008
  • FBG (Fiber Bragg Grating) sensors and optical fibers were embedded into CFRP dry preforms before resin impregnation in VaRTM (Vacuum-assisted Resin Transfer Molding). The embedding location was the interface between the skin and the stringer in a CFRP-stiffened panel. The reflection spectra of the FBG sensors monitored the strain and temperature changes during all the molding processes. The internal residual strains of the CFRP panel could be evaluated during both the curing time and the post-curing time. The temperature changes indicated the differences between the dry preform and the outside of the vacuum bagging. After the molding, four-point bending was applied to the panel for the verification of its structural integrity and the sensor capabilities. The optical fibers were then used for the newly-developed PPP-BOTDA (Pulse-PrePump Brillouin Optical Time Domain Analysis) system. The long-range distributed strain and temperature can be measured by this system, whose spatial resolution is 100 mm. The strain changes from the FBGs and the PPP-BOTDA agreed well with those from the conventional strain gages and FE analysis in the CFRP panel. Therefore, the fiber-optic sensors and its system were very effective for the evaluation of the VaRTM composite structures.

Investigation of the Relationships between Beginning Elementary Teachers' Beliefs about the Nature of Science, and Science Leaching and Learning Context (초등 초임교사의 과학의 본성에 대한 신념과 과학 교수-학습 활동과의 관련성)

  • Yang Il-Ho;Han Ki-Gab;Choi Hyun-Dong;Oh Chang-Ho;Cho Hyun-Jun
    • Journal of Korean Elementary Science Education
    • /
    • v.24 no.4
    • /
    • pp.399-416
    • /
    • 2005
  • The purpose of this study was to examine the relationship between science teaching practices and beliefs about the nature of science. Defining teachers' beliefs as a broad construct, the researcher tried to examine not only the teachers' understanding about the nature of science, but also the effect and reflection in science teaching practices with regards to the nature of science. Guiding research questions were how the teachers' science teaching practices reflected their beliefs about the nature of science. The methodology of this study was qualitative approach that included interviews, classroom observations, and instructional materials. At an urban area of Korea, five beginning elementary teacher was chosen. The cross-case and grounded theory study design were adopted as data analysis process. The results of data analysis were checked by teachers for internal validity. This study identified the teachers' beliefs about the nature of science suggested by many researchers and revealed that these teachers' beliefs reflected a little in science teaching practices. On the occasion it was reflected, restricted merely within the narrow limits the way to teach the concepts and contents presented in science curriculum. In addition, some of the obstacles that these teachers' beliefs did not reflect the science teaching practices with regards to the nature of science were investigated in this study.

  • PDF

Fabrication of 365 nm Wavelength High Transmittance Silicone Resin TIR Lens and High Directivity Light Source Module for Exposure System (365 nm 파장대역 고투과율 실리콘 수지 TIR 렌즈 및 고지향성 노광기 광원모듈 제작)

  • Sung, Jun Ho;Yu, Soon Jae;Anil, Kawan;Jung, Mee Suk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.31 no.4
    • /
    • pp.267-271
    • /
    • 2018
  • A high directivity TIR (total internal reflection) lens in the UV-A region was designed using a silicone resin, and a UV light source module with a maximum irradiation density of $150mW/cm^2$ was fabricated. The beam angle of the TIR lens was designed to be $8.04^{\circ}$ and the maximum diameter of the TIR lens was Ø13.5. A silicone resin having a UV transmittance of 93% and a refractive index of 1.4 at a wavelength of 365 nm was used, and the lens was manufactured using an aluminum mold, from which silicone could be easily released. The module was fabricated in a metal printed circuit board of COB (chip on board) type using a $0.75{\times}0.75mm^2$ UV chip. A jig was used to adjust the focal length between lens and chip and to fix the position of the lens. The optical characteristics such as illumination distributions of the lens and module were designed using 'LightTools' optical simulation software. The heat dissipation system was designed to use a forced-air cooling method using a heat-sink and fan.

Development of Formative Constructs and Measurements for Performance Evaluation of Information Systems (정보시스템 성과평가를 위한 형성적 구성변수(Constructs) 및 측정지표 개발)

  • Kim, Sanghoon;Kim, Changkyu
    • Journal of Information Technology Services
    • /
    • v.11 no.4
    • /
    • pp.135-151
    • /
    • 2012
  • Traditionally in IS studies, the relationship between construct and its measurement items tends to be assumed to be reflective, meaning that the measurements are a reflection of the construct. In reality, however, the nature of the construct can be often formative, which means that its measurement items describe and define the construct rather than vice versa. The purpose of this study was to investigate theoretical and empirically-analysed differences between formative construct and reflective construct through comprehensive interdisciplinary literature review. And then on the basis of these differences, we intended to derive the rule of specifying whether the construct is formative or reflective and propose the methodology of testing the validity(content validity, construct validity, internal consistency and external construct) of formative construct and its measurements, differentiated from that in the case of reflective construct. Also, we suggested the concrete statistical testing methods such as VTT(Vanishing Tetrad Test), MIMIC(Multiple Indicators and Multiple Causes) test and multi-collinearity test. In order to examine the applicability of this methodology to developing the constructs for performance evaluation of IS(Information Systems), we tried to identify its attribute(formative or reflective) and test the validity for the construct arbitrarily chosen among them which had been derived in our previous IS performance evaluation study by using this methodology. The result of the examination was that the methodology proposed in this study was significantly valid and effective in the area of IS performance evaluation.

Scale Development of Wisdom among Korean Elderly ('한국노인의 지혜척도' 개발에 관한 연구)

  • Sung, Ki-Wol;Lee, Shin-Young;Park, Jong-Han
    • 한국노년학
    • /
    • v.30 no.1
    • /
    • pp.65-80
    • /
    • 2010
  • Purpose: The purpose of this study was to develop a wisdom scale among Korean elderly with high validity and reliability. Method: The process of the development of this scale follows: A conceptual framework was identified based on literature a review of the elderly and discussion with experts in physiology and sociology. Total 128 items were developed. Through reliability testing, factor analysis, 60 preliminary items, and 4-points scale were selected. By a means of the internal consistency for 60 items, 33 items were deleted. Finally, 27 items were remained. To verity 27 items, factor analysis, reliability testing, and correlation were done. Data were collected from 480 elderly subjects in Daegu, Kyungpook Province, and Busan, Kyungnam Province from August, 2008 to February, 2009. Results: From the results of the factor analysis for 27 items, 3 factors were extracted. These factors were labeled as 'empathic emotion', 'self-reflection', and 'bitter experience of life'. Cronbach's Alpha for the 27 items was .921 and correlation coefficient of ego-integrity was .69. Conclusion: An exploratory study of the variables related to wisdom among the elderly is needed for criterion validity of this scale. A study on wisdom for different age groups is needed for re-verification.

Kongzi's Practical Teachings on De 德 (Moral Virtues): Ren 仁 (Benevolence) and Li 禮 (Ritual Propriety) as the Main Topics (공자(孔子)의 실천적 덕론(德論) - 인(仁)과 예(禮)를 중심으로 -)

  • Chi, Chun-Ho
    • The Journal of Korean Philosophical History
    • /
    • no.41
    • /
    • pp.223-246
    • /
    • 2014
  • The main concern of classical Confucianism, which has Kongzi as its main thinker, is how one can attain moral perfection. In this respect, all of the Confucian teachings can be characterized as an attempt to expound the nature of sages or gentlemen who are believed to attain moral perfection. In Confucianism, de 德 (moral virtue) refers to moral principles or the attributes of things, and it also signifies moral qualities and abilities of humans which are believed to be bestowed by the moral source. Kongzi substantiated the details and practical methods of de, through his teachings of ren as its internal principle and li as its external form. in this way, he put a special emphasis on moral practicality of de. To study Kongzi's practical moral teachings focusing on de can be understood as a reflection on current educational issues.

Problems of Teaching Pupils of Non-Specialized Classes to Program and Ways to Overcome Them: Local Study

  • Rudenko, Yuliya;Drushlyak, Marina;Osmuk, Nataliia;Shvets, Olha
    • International Journal of Computer Science & Network Security
    • /
    • v.22 no.1
    • /
    • pp.105-112
    • /
    • 2022
  • The development and spread of IT-technologies has raised interest in teaching programming pupils. The article deals with problems related to programming and ways to overcome them. The importance of programming skills is emphasized, as this process promotes the formation of algorithmic thinking of pupils. The authors determined the level of pupils' interest to programing learning depending on the age. The analysis has showed that the natural interest of younger pupils in programming is decreasing over the years and in the most productive period of its study is minimized. It is revealed that senior school pupils are characterized by low level of interest in the study of programming; lack of motivation; the presence of psychological blocks on their own abilities in the context of programming; law level of computer science understanding. To overcome these problems, we conducted the second stage of the experiment, which was based on a change in the approach to programing learning, which involved pupils of non-specialized classes of senior school (experimental group). During the study of programming, special attention was paid to the motivational and psychological component, as well as the use of game technologies and teamwork of pupils. The results of the pedagogical experiment on studying the effectiveness of teaching programming for pupils of nonspecialized classes are presented. Improvement of the results provided the use of social and cognitive motives; application of verbal and non-verbal, external and internal means; communicative attacks; stimulation and psychological setting; game techniques, independent work and reflection, teamwork. The positive effect of the implemented methods is shown by the results verified by the methods of mathematical statistics in the experimental and control groups of pupils.

The Development of Automated Personalized Self-Care (APSC) Program for Patients with Type 2 Diabetes Mellitus (제2형 당뇨병 환자를 위한 자동 맞춤형 셀프케어 프로그램 개발)

  • Park, Gaeun;Lee, Haejung;Khang, Ah Reum
    • Journal of Korean Academy of Nursing
    • /
    • v.52 no.5
    • /
    • pp.535-549
    • /
    • 2022
  • Purpose: The study aimed to design and develop an automated personalized self-care (APSC) program for patients with type 2 diabetes mellitus. The secondary aim was to present a clinical protocol as a mixed-method research to test the program effects. Methods: The APSC program was developed in the order of analysis, design, implementation, and evaluation according to the software development life cycle, and was guided by the self-regulatory theory. The content validity, heuristics, and usability of the program were verified by experts and patients with type 2 diabetes mellitus. Results: The APSC program was developed based on goal setting, education, monitoring, and feedback components corresponding to the phases of forethought, performance/volitional control, and self-reflection of self-regulatory theory. Using the mobile application, the participants are able to learn from educational materials, monitor their health behaviors, receive weekly-automated personalized goals and feedback messages, and use an automated conversation system to solve the problems related to self-care. The ongoing two-year study utilizes a mixed method design, with 180 patients having type 2 diabetes mellitus randomized to receive either the intervention or usual care. The participants will be reviewed for self-care self-efficacy, health behaviors, and health outcomes at 6, 12, 18, and 24 months. Participants in the intervention group will be interviewed about their experiences. Conclusion: The APSC program can serve as an effective tool for facilitating diabetes health behaviors by improving patients' self-care self-efficacy and self-regulation for self-care. However, the clinical effectiveness of this program requires further investigation.