• Title/Summary/Keyword: lens process

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Real-Time Textile Dimension Inspection System Using Zone-Crossing Method, Distortion Angle Classifier and Gray-Level Co-occurrence Matrix Features (영역교차법, 왜곡각 분류자 및 명암도 상관행렬 특징자를 이용한 실시간 섬유 성량 검사 시스템)

  • 이응주;이철희
    • Journal of Korea Multimedia Society
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    • v.3 no.2
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    • pp.112-120
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    • 2000
  • In this paper, we implement a real-time textile dimension inspection system. It can detect various types of real defects which determine the quality of fabric product, defect positions of textile, classify the distortion angel of moving textile and the density. In the implemented system, we measure the density of textile using zone-crossing method with optical lens to solve the noise and real-time problems. And we compensate distortion angel of textile with the classification of distortion types using gaussian gradient and mean gradient features. And also, it detecs real defects of textile and its positions using gray level co-occurrence matrix features. The implemented texile demension inspection systemcan inspect textile dimensions such as density, distortion angle, defect of textile and defect position at real-time. In the implemented proposed texitile dimension inspection system, It is possible to calculate density and detect default of textile at real-time dimension inspection system, it is possible to calculate density and detect default of textile at textile states throughout at all the significant working process such as dyeing, manufacturing, and other texitle processing.

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Automatic Target Recognition for Camera Calibration (카메라 캘리브레이션을 위한 자동 타겟 인식)

  • Kim, Eui Myoung;Kwon, Sang Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.6
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    • pp.525-534
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    • 2018
  • Camera calibration is the process of determining the parameters such as the focal length of a camera, the position of a principal point, and lens distortions. For this purpose, images of checkerboard have been mainly used. When targets were automatically recognized in checkerboard image, the existing studies had limitations in that the user should have a good understanding of the input parameters for recognizing the target or that all checkerboard should appear in the image. In this study, a methodology for automatic target recognition was proposed. In this method, even if only a part of the checkerboard image was captured using rectangles including eight blobs, four each at the central portion and the outer portion of the checkerboard, the index of the target can be automatically assigned. In addition, there is no need for input parameters. In this study, three conditions were used to automatically extract the center point of the checkerboard target: the distortion of black and white pattern, the frequency of edge change, and the ratio of black and white pixels. Also, the direction and numbering of the checkerboard targets were made with blobs. Through experiments on two types of checkerboards, it was possible to automatically recognize checkerboard targets within a minute for 36 images.

Who Made Southeast Asia? Personages, Programs and Problems in the Pursuit of a Region

  • King, Victor T.
    • SUVANNABHUMI
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    • v.12 no.2
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    • pp.157-200
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    • 2020
  • This paper explores critically and historically some of the popular academic views concerning the development of the study of Southeast Asia through the lens of the contributions of particular scholars and institutions. Within the broad field of Southeast Asian Studies the focus is on the disciplines of geography, history and ethnology. There are certain views concerning the development of scholarship on Southeast Asia which continue to surface and have acquired, or are in the process of acquiring "mythical" status. Among the most enduring is the claim that the region is a post-Second World War construction primarily arising from Western politico-strategic and economic preoccupations. More specifically, it is said that Southeast Asian Studies for a considerable period of time has been subject to the American domination of this field of scholarship, located in programs of study in such institutions as Cornell, Yale and California, Berkeley, and, within those institutions, focused on particular scholars who have exerted considerable influence on the directions which research has taken. Another is that, based on the model or template of Southeast Asian Studies (and other area studies projects) developed primarily in the USA, it has distinctive characteristics as a scholarly enterprise in that it is multidisciplinary, requires command of the vernacular, and assigns special importance to what has been termed 'groundedness' and historical, geographical and cultural contextualization; in other words, a Southeast Asian Studies approach as distinct from disciplinarybased studies addresses local concerns, interests, perspectives and priorities through in-depth, on-the-ground, engaged scholarship. Finally, views have emerged that argue that a truly Southeast Asian Studies project can only be achieved if it is based on a set of locally-generated concepts, methods and approaches to replace Western ethnocentrism and intellectual hegemony.

Characteristics of Rhenium-Iridium coating thin film on tungsten carbide by multi-target sputter

  • Cheon, Min-Woo;Kim, Tae-Gon;Park, Yong-Pil
    • Journal of Ceramic Processing Research
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    • v.13 no.spc2
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    • pp.328-331
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    • 2012
  • With the recent development of super-precision optical instruments, camera modules for devices, such as portable terminals and digital camera lenses, are increasingly being used. Since an optical lens is usually produced by high-temperature compression molding methods using tungsten carbide (WC) alloy molding cores, it is necessary to develop and study technology for super-precision processing of molding cores and coatings for the core surface. In this study, Rhenium-Iridium (Re-Ir) thin films were deposited onto a WC molding core using a sputtering system. The Re-Ir thin films were prepared by a multi-target sputtering technique, using iridium, rhenium, and chromium as the sources. Argon and nitrogen were introduced through an inlet into the chamber to be the plasma and reactive gases. The Re-Ir thin films were prepared with targets having a composition ratio of 30 : 70, and the Re-Ir thin films were formed with a 240 nm thickness. Re-Ir thin films on WC molding core were analyzed by scanning electron microscope (SEM), atomic force microscope (AFM), and Ra (the arithmetical average surface roughness). Also, adhesion strength and coefficient friction of Re-Ir thin films were examined. The Re-Ir coating technique has received intensive attention in the coating processes field because of promising features, such as hardness, high elasticity, abrasion resistance and mechanical stability that result from the process. Re-Ir coating technique has also been applied widely in industrial and biomedical applications. In this study, WC molding core was manufactured, using high-performance precision machining and the effects of the Re-Ir coating on the surface roughness.

Elemental Composition of the Soils using LIBS Laser Induced Breakdown Spectroscopy

  • Muhammad Aslam Khoso;Seher Saleem;Altaf H. Nizamani;Hussain Saleem;Abdul Majid Soomro;Waseem Ahmed Bhutto;Saifullah Jamali;Nek Muhammad Shaikh
    • International Journal of Computer Science & Network Security
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    • v.24 no.6
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    • pp.200-206
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    • 2024
  • Laser induced breakdown spectroscopy (LIBS) technique has been used for the elemental composition of the soils. In this technique, a high energy laser pulse is focused on a sample to produce plasma. From the spectroscopic analysis of such plasma plume, we have determined the different elements present in the soil. This technique is effective and rapid for the qualitative and quantitative analysis of all type of samples. In this work a Q-switched Nd: YAG laser operating with its fundamental mode (1064 nm laser wavelength), 5 nanosecond pulse width, and 10 Hz repetition rate was focused on soil samples using 10 cm quartz lens. The emission spectra of soil consist of Iron (Fe), Calcium (Ca), Titanium (Ti), Silicon (Si), Aluminum (Al), Magnesium (Mg), Manganese (Mn), Potassium (K), Nickel (Ni), Chromium (Cr), Copper (Cu), Mercury (Hg), Barium (Ba), Vanadium (V), Lead (Pb), Nitrogen (N), Scandium (Sc), Hydrogen (H), Strontium (Sr), and Lithium (Li) with different finger-prints of the transition lines. The maximum intensity of the transition lines was observed close to the surface of the sample and it was decreased along the axial direction of the plasma expansion due to the thermalization and the recombination process. We have also determined the plasma parameters such as electron temperature and the electron number density of the plasma using Boltzmann's plot method as well as the Stark broadening of the transition lines respectively. The electron temperature is estimated at 14611 °K, whereas the electron number density i.e. 4.1 × 1016 cm-3 lies close to the surface.

Design and Fabrication for the Development of Auto Pattern Maker (자동취형기 개발을 위한 설계 및 제작)

  • Lee, Young-Il;Kim, Jung-Hee;Park, Jee-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.3
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    • pp.231-239
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    • 2013
  • Purpose: To design and fabricate the auto pattern maker for the development. Methods: we got the necessary data, needed in design, by using CAD. Based on the these data, we fabricated the trial product for the development of the auto pattern maker. Results: The auto pattern maker were composed with combinations of many elements; pattern making assembly, control panel, frame attachment and prober unit. The pattern making assembly was comprised of the cutter, the pattern holder, pattern remover and silence cover which could minimize the sound during the cutting process. The control panel was designed to be connected and operated with the main printed circuit board. The prober could get the eye shape data by scanning of 1.8 degrees around the groove of the frame through the encoding data according to the address. After starting, scanning was carried out in two passes, i.e. one right-handed and one left-handed. Communication connector could send the eye shape data from auto pattern maker to outer system with the RS232C transmission system. By using the one-way analysis of variance, we got the error rate of cut pattern size for ${\Phi}22mm$, ${\Phi}55mm$ and ${\Phi}62mm$. Because F-value was 0.510 and p-value was 0.601, no statistically significant differences were found. Also, the mean cutting error of the auto pattern maker was 0.0274 mm. Conclusions: we could succeed in making the trial product by applying it to the development of the auto pattern maker. The role of this auto pattern maker is to find a exact required size of lens to fit the frame by measuring the frame. The acquired data are transferred to outer system for grinding and finishing with patternless process. Also, the trial product can produce pattern to fit the frame. Therefore, it was confidently expected that the optometrists could handily produce pattern to fit the frame with this trial product and dispense the ophthalmic lens because of its efficiency and convenience compared to the past.

Photocatalyst characteristic of WO3 thin film with sputtering process (스퍼터링법에 의해 제작된 WO3 박막의 광분해 특성)

  • Lee, Boong-Joo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.420-424
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    • 2016
  • In this study, we developed photocatalytic technology to address the emerging serious problem of air pollution through indoor air cleaning. A single layer of $WO_3$ was prepared by using the dry process of general RF magnetron sputtering. At a base vacuum of $1.8{\times}10^{-6}$[Torr], the optical and electrical properties of the resulting thin films were examined for use as a transparent electrode as well as a photocatalyst. The single layer of $WO_3$ prepared at an RF power of 100 [W], a pressure of 7 [mTorr] and Ar and $O_2$ gas flow rates of 70 and 2 sccm, respectively, showed uniform and good optical transmittance of over 80% in the visible wavelength range from 380 [nm] to 780 [nm]. The optical catalyst characteristics of the $WO_3$ thin film were examined by investigating the optical absorbance and concentration variance in methylene blue, where the $WO_3$ thin film was immersed in the methylene blue. The catalytic characteristics improved with time. The concentration of methylene blue decreased to 80% after 5 hours, which confirms that the $WO_3$ thin film shows the characteristics of an optical catalyst. Using the reflector of a CCFL (cold cathode fluorescent lamp) and the lens of an LED (lighting emitting diode), it is possible to enhance the air cleaning effect of next-generation light sources.

Study on Fiber Laser Annealing of p-a-Si:H Deposition Layer for the Fabrication of Interdigitated Back Contact Solar Cells (IBC형 태양전지 제작을 위한 p-a-Si:H 증착층의 파이버 레이저 가공에 관한 연구)

  • Kim, Sung-Chul;Lee, Young-Seok;Han, Kyu-Min;Moon, In-Yong;Kwon, Tae-Young;Kyung, Do-Hyun;Kim, Young-Kuk;Heo, Jong-Kyu;Yoon, Ki-Chan;Yi, Jun-Sin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.430-430
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    • 2008
  • Using multi plasma enhanced chemical vapor deposition system (Multi-PECVD), p-a-Si:H deposition layer as a $p^+$ region which was annealed by laser (Q-switched fiber laser, $\lambda$ = 1064 nm) on an n-type single crystalline Si (100) plane circle wafer was prepared as new doping method for single crystalline interdigitated back contact (IBC) solar cells. As lots of earlier studies implemented, most cases dealt with the excimer (excited dimer) laserannealing or crystallization of boron with the ultraviolet wavelength range and $10^{-9}$ sec pulse duration. In this study, the Q-switched fiber laser which has higher power, longer wavelength of infrared range ($\lambda$ = 1064 nm) and longer pulse duration of $10^{-8}$ sec than excimer laser was introduced for uniformly deposited p-a-Si:H layer to be annealed and to make sheet resistance expectable as an important process for IBC solar cell $p^+$ layer on a polished n-type Si circle wafer. A $525{\mu}m$ thick n-type Si semiconductor circle wafer of (100) plane which was dipped in a buffered hydrofluoric acid solution for 30 seconds was mounted on the Multi-PECVD system for p-a-Si:H deposition layer with the ratio of $SiH_4:H_2:B_2H_6$ = 30:120:30, at $200^{\circ}C$, 50 W power, 0.2 Torr pressure for 20 minutes. 15 mm $\times$ 15 mm size laser cut samples were annealed by fiber laser with different sets of power levels and frequencies. By comparing the results of lifetime measurement and sheet resistance relation, the laser condition set of 50 mm/s of mark speed, 160 kHz of period, 21 % of power level with continuous wave mode of scanner lens showed the features of small difference of lifetime and lowering sheet resistance than before the fiber laser treatment with not much surface damages. Diode level device was made to confirm these experimental results by measuring C-V, I-V characteristics. Uniform and expectable boron doped layer can play an important role to predict the efficiency during the fabricating process of IBC solar cells.

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The Political Geography of Place Names : The Decisions of City Names in the Process of Administrative District Reorganization (지명의 정치지리학: 행정구역개편으로 인한 시 명칭 결정을 사례로)

  • Chi, Sang-Hyun
    • Journal of the Korean association of regional geographers
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    • v.18 no.3
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    • pp.310-325
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    • 2012
  • Human being has used place names to differentiate one place from another. Place names are the products of collective human cognition in that a place name is chosen when it successfully represents the identity of a place. In addition, place names have been changed by the competition and struggle between social agencies and the political imperatives of hegemonic groups to impose their identity on the places. Recent geographic studies on place names have focused on the social and political processes behind the change of place names. In this vein, the purpose of this study is investigating the debates on the decision of city names in the process of the administrative reorganization in mid 1990s by the lens of political geography. Residents in cities and counties tried to justify their arguments by emphasizing historical backgrounds and popularity of their names. Additionally, economic power and potential were mobilized for the political resources to win over the battle over city names. The result, however, shows that the decision of newly consolidated cities' name was mainly made by the amount of political resources, such as population and number of seats in local assemblies. Several regions tried to use city names to negotiate with counterparts. In sum, the decision of place names is the product of political competitions, and the place name becomes the symbol of territorial identity. Place names have been in the center of disputes in local politics even after the name was decided, which suggest further studies on reasonable solution to mitigate the disputes to be expected when additional reorganization of administrative districts.

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Investigation of Molding Characteristics in Injection Compression Molding According to Molding Conditions through Birefringence (사출압축성형에서 복굴절을 통한 성형조건에 따른 성형특성 고찰)

  • Lee, Dan Bi;Nam, Yun Hyo;Lyu, Min-Young
    • Polymer(Korea)
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    • v.38 no.2
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    • pp.193-198
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    • 2014
  • Lens and DVD require high quality of optical property. Conventional injection molded products contain high residual stress and this invokes birefringence since high cavity pressure and high temperature variation are involved in a molding process. Thus these products are often molded by injection compression molding in order to minimize the residual stress through reducing cavity pressure and uniform cavity pressure. In this study, molding parameters affecting molding quality such as property uniformity in injection compression molding were investigated through experiment. Molding quality deviations among the cavities in multi-cavity mold were also studied. Transparent resins, PC and PS were used in this study. Compression gap, compression speed, compression force, and compression delay time for processing variables in injection compression molding were applied in experiment. Compression force, compression delay time, and compression gap significantly affected the optical property of product. The degree of influence of process variable on the product quality was different in different resins. This implies that the optimal operational conditions in injection compression molding existed for each resin according to flow property.