• Proceedings of the Korea Crystallographic Association Conference
• /
• 2002.11a
• /
• pp.5-6
• /
• 2002

The new spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) .has been recently developed in KRISS in collaboration with PTI (Russia). The spectrometer allows to perform research using the XAFS, SXAFS, XANES techniques (D.C.Koningsberger and R.Prins, 1988) as well as the number of techniques from XIEES field(L.A.Bakaleinikov et all, 1992). The experiments may be carried out with registration of transmitted through the sample x-rays (to investigate bulk samples) or/and total electron yield (TEY) from the sample surface that gives the high (down to several atomic mono-layers in soft x-ray region) near surface sensitivity. The combination of these methods together give the possibility to obtain a quantitative information on elemental composition, chemical state, atomic structure for powder samples and solids, including non-crystalline materials (the long range order is not required). The optical design of spectrometer is made according to Johannesson true focusing schematics and presented on the Fig.1. Five stepping motors are used to maintain the focusing condition during the photon energy scan (crystal angle, crystal position along rail, sample goniometer rail angle, sample goniometer position along rail and sample goniometer angle relatively of rail). All movements can be done independently and simultaneously that speeds up the setting of photon energy and allows the using of crystals with different Rowland radil. At present six curved crystals with different d-values and one flat synthetic multilayer are installed on revolver-type monochromator. This arrangement allows the wide range of x-rays from 100 eV up to 25 keV to be obtained. Another 4 stepping motors set exit slit width, sample angle, channeltron position and x-ray detector position. The differential pumping allows to unite vacuum chambers of spectrometer and x-ray generator avoiding the absorption of soft x-rays on Be foil of a window and in atmosphere. Another feature of vacuum system is separation of walls of vacuum chamber (which are deformed by the atmospheric pressure) from optical elements of spectrometer. This warrantees that the optical elements are precisely positioned. The detecting system of the spectrometer consists of two proportional counters, one scintillating detector and one channeltron detector. First proportional counter can be used as I/sub 0/-detector in transmission mode or by measuring the fluorescence from exit slit edge. The last installation can be used to measure the reference data (that is necessary in XANES measurements), in this case the reference sample is installed on slit knife edge. The second proportional counter measures the intensity of x-rays transmitted through the sample. The scintillating detector is used in the same way but on the air for the hard x-rays and for alignment purposes. Total electron yield from the sample is measured by channeltron. The spectrometer is fully controlled by special software that gives the high flexibility and reliability in carrying out of the experiments. Fig.2 and fig.3 present the typical XAFS spectra measured with spectrometer.

• Korean Journal of Digital Imaging in Medicine
• /
• v.14 no.2
• /
• pp.39-46
• /
• 2012

Purpose : The purpose of this study was to reduce Entrance Surface Dose and maintain image quality by changing Source to Image receptor Distance. And we'd like to compare ESD on this study to DRLs in other contries. Materials and Methods : We used indirect DR system(Definium 8000, General Electric, USA)and phantom(ART-200X, Flukebiomedical, USA),glass dosimeters(GD-352M, Asahi Techno Glass, Japan)for this study. The imagies were obtained throuh 80kVp fixed, and different tube currents using AEC mode in $16{\times}16$(inch) field size and changing Source to Image receptor Distance from 100 cm to 130 cm per 10 cm unit. The phantom with attaching 5 glass dosimeters on abdomonal skin was set at supine and erect position as a anterioposterial projection on detector For measuring Entrance Surface Dose. Image analysis was conducted by histograms of Image J(1.46r) which was given from National Institutes of Health(NIH). Results : Due to inverse square law of distance, the tube currents were increasing 42.6 % in supine position and 32.6 % in erect position according to the change of Source to Image receptor Distance. While Entrance Surface Doses were rapidly decreasing 14.2 % in supine position and 29.4 % in erect position according to the change of Source to Image receptor Distance. As the results of histogram using Image J, pixel mean values from 100 cm to 110 cm, 120 cm and 130 cm were decreasing each 1.4%, 2.5%, 2.7%, 4.5%, 2.2 %, 5.8 % in supine, erect position. While standard deviations from 100 cm to 110 cm, 120 cm and 130 cm were increasing each 1.4 %, 2.5 %, 2.5 %, 4.0 %, 2.0 %, 4.9 % Consequently, there are no significant differences in abdomen images taken. Conclusion: As the results described above, we strongly recommend using long Sourceto Image receptor Distance than 100cm that we have been using. So, we should deliver less Entrance Surface Dose to the patients while maintaining image quality in abdomen radiography.

• Journal of Applied Biological Chemistry
• /
• v.63 no.3
• /
• pp.275-282
• /
• 2020

As pesticide safety was extended to agricultural environments and Positive List System was carried out, Pesticide safety management in soils has become even more important. To improve pesticide safety in soils needs the degradation technology of the residues in soils and reduce plant uptake of pesticides. In this study, biochars and quicklime as the degradation methods of pesticides (azoxystrboin, procymidone and tricyclazole) were used to identify the reduction effects. The experimental methods were putting biochars and quicklimes (0, 0.5, 1.0, 2.0% per 15 cm soil weight) in soils and analyzing the pesticide residues at 0, 10, 20, 35, 50 day. To identify the reduction effects of uptake from soil to korean cabbages (roots, leave, stems) by biochar treatment, the residues in samples were analyzed. As a results, azoxystrobin (36-96%), procymidone (40-117%) and tricyclazole (26-83%) were reduced in soils when treated with 2.0% quicklime (p<0.05). There were no reduction effect in soils when treated with 1.0% or less biochar. However, the amounts of residues translocated to roots (0.11-1.62 mg/kg), leave (0.05-0.29 mg/kg), stems (0.06-0.1 mg/kg) were reduced treated with 2.0% biochar treatments. The biochar and quicklime can be applicable to agricultural field to improve pesticide safety in soils.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.40 no.3
• /
• pp.59-65
• /
• 2017

The purpose of this study is to investigate the factors and effects of job stress of construction workers on construction accidents and turnover intention in order to improve the field work environment of construction industry which shows higher industrial accidents than other industries. To this end, research models and hypotheses were established based on previous research, and the questionnaire was distributed to 10 construction companies in Daejeon, Sejong, and Chungcheong provinces. The 301 data collected were performed statistical analysis such as basic statistical analysis, factor analysis, reliability analysis, correlation analysis, regression analysis, and logistic regression analysis using the statistical package (IBM SPSS 22). The results of this study are summarized as follows. First, job stress has a significant effect on accident occurrence. Among the sub-factors of job stress, there was positive (+) influence on work culture and relationship conflict between peers, and organizational system had negative influence. Job demands, compensation incompetence, and job instability were not statistically significant. Therefore, it is necessary to concentrate on the factors of work culture, organizational system, and relationship conflict in the construction site. Second, job stress has positive effect on turnover intention. Job stress, inadequacy of compensation, and work culture were positively related to turnover intention. Third, job demands have a slightly greater impact than compensatory inadequacies. The factors that make the job turnover more important are the excessive job burdens such as respect, internal motivation, responsibility rather than expectation non-conformity, time pressure, increase of work load. Therefore, in order to reduce the turnover intention of the construction worker, it is necessary to pay attention to improvement of the job requirement. Fourth, the worker's job stress could overcome by exercise and fatigue elimination, work environment management, and self-opening for others. It is necessary to establish a work environment management system for counseling and intimacy formation to open up the exercise and fatigue relief program of the workers at the construction site and to open themselves between the workers and the supervisors.

• Journal of Digital Convergence
• /
• v.16 no.10
• /
• pp.199-204
• /
• 2018

The purpose of this study is to investigate the factors and reasons for hiring kindergarten teachers and to provide information for successful employment to the college. 12 private kindergarten chiefs over 10 years of experience were conducted in - depth interviews. In-depth interview data were analyzed using open coding analysis. 11 sub - factors of each core concept were derived, and they were nominated as 4 outline (character, sociality, personality & professionalism factors). All of the researchers perceived the sincerity, interpersonal stability, honesty, and ability to perform the curriculum as the most important factors to consider, and the teacher with good personality was perceived as the precondition of successful teacher's job performance. In the college, through the production of portfolios by subject, we raised the necessity of institutionalization of educational volunteer activities such as vacation - based education in addition to on - the - spot education at school and development of liberal arts curriculum to develop capacity for community life. And to develop and operate a field-oriented comparative education program to strengthen the competence of the majors.

• Journal of the Korean earth science society
• /
• v.38 no.1
• /
• pp.49-63
• /
• 2017

The geochemical results of the Chunyang granites located in the northeastern part of the Yeongnam Massif, indicate that these rocks have characteristics of calc-alkaline series in the sub-alkaline field, I-type and peraluminous. Most of the geochemical features in major and trace elements show systematic trends, which are similar to differentiation trends of the general Jurassic granitoids in South Korea. The Chunyang granite is largely enriched in mobile LILE (Sr, K, Rb and Ba) relatively immobile HFSE. They show LREE enriched patterns [$(La/Lu)_{CN}=41.8-73.2$] with a slightly negative Eu anomaly [$(Eu/Eu^*)_{CN}=0.89-1.10$]. There are no meaningful correlations in major and trace elements between the Chunyang granites and the Buseok plutonic rock which is the main unit of the Yeongju batholith. This result may suggest that these two plutonic rocks be not derived from the same parent magma. Tectonic discrimination diagrams indicate that the Chunyang granite was formed in volcanic arc environments. These geochemical characteristics results suggest that the Chunyang granite must have been generated at the active continental margin during the subduction of the Jurassic proto-Pacific plate.

• Journal of the Optical Society of Korea
• /
• v.13 no.1
• /
• pp.8-14
• /
• 2009

In a laser-plasma wakefield accelerator, the ponderomotive force of an ultrashort high intensity laser pulse excites a longitudinal wave or plasma bubble in a way similar to the excitation of a wake wave behind a boat as it propagates on the water surface. Electric fields inside the plasma bubble can be several orders of magnitude higher than those available in conventional RF-based particle accelerator facilities which are limited by material breakdown. Therefore, if an electron bunch is properly phase-locked with the bubble's acceleration field, it can gain relativistic energies within an extremely short distance. Here, in the bubble regime we show the generation of stable and reproducible sub GeV, and GeV-class electron beams. Supported by three-dimensional particle-in-cell simulations, our experimental results show the highest acceleration gradients produced so far. Simulations suggested that the plasma bubble elongation should be minimized in order to achieve higher electron beam energies.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.7
• /
• pp.180-189
• /
• 2014

Display quality assessment has been a long standing issue due to the diversity of display devices and the rapid growth of display technology. The conventional display quality assessment methods are mostly those methods which evaluate qualities of a display by measuring physical quantities, but the results from the methods are not equal to the perceived results which are acquired with subjective experiments. Thus, we need to solve the above contrariety as well as establish the quantitative correlation between physical and perceived results. This paper proposes the systematic method of evaluating relative perceived qualities among various display devices and quantifies these relative perceived qualities. The proposed method is based on Analytic Network Process(ANP), which is one of the most popular decision making methods in the business administration field. We also adopted three evaluation criteria, which consist of color, shape and depth, in order to reflect the human visual system and chose eight sub-criteria related to display characteristics via question investigation. We carried out a subjective experiment and the proposed method which evaluated perceived qualities of two display devices(TFT-LCD, OLED) in order to prove the similarity between their results. As a result, it is proved that the order relationship between perceived qualities was the same as the order of results got through the subjective experiment.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.9 no.4
• /
• pp.145-152
• /
• 2009

Domestic Kori-1 MCR was partially modified in 2007 and will be renovated entirely in 2013. Digital devices partially replacing original analog devices have been introduced and standard alone computer systems such as SPDS have been integrated into the plant computer. Upgrading KSNP's MCR based on the ditalization is planned for 2015. However, the site engineers and operators are reluctant to the advanced systems. Therefore, a prototype for the KSNP's advanced MCR has been developed to increase the acceptance level of the operators and field engineers and also, to evaluate user interfaces and I&C architecture. For enhancing support of the operators' work, a P&ID based display system composed of multi-layers, which are linked through a context sensitive menu each other, has been adopted. The $1^{st}$ layer displays a simplified P&ID, the $2^{nd}$ layer control related diagrams such as controllers and logic diagrams, the $3^{rd}$ layer trends, etc. The end point view of MCR for KSNP is also suggested considering reliability and operability of the digital systems. Additionally, modernization strategies over the overhaul periods, that do not have much impact on operation and configuration efforts are suggested.

• Journal of architectural history
• /
• v.3 no.1
• /
• pp.57-82
• /
• 1994

This paper is the result of the researches and the field surveys of the villages and the dwellings of Korean immigrants in Yien-Pien area, north-eastern China. This study aims to persue both of the origin and the process of development of their settlements and dwelling types from late 19C to the present. Their processes are too complex to analysis by single view-point. I have eyes to interprete them from three pionts; 1)correspondences between the dwelling types and the econo-political history of their region, 2)cultural assimilation with the native dwelling types, and 3)the direction of their modernization with the economical development of modern China. Three village types have been pioneered; 1)the villages of indivisual immigration, 2)the villages of planned group immigration, and 3)the villages of socilistic reform villages of 1) were composed of organic village patterns and various shaped dwelling lots on the sloped site; villages both of 2) and 3), gird patterns and uniformed lots on open fields. Historically, villages of 1) were pioneered before 1931; villages of 2), 1936-1945; villages of 3), from 1945. Each of dwelling types had strong relations with the village types to which it belonged. Before 1931, dwellings were built up based on so called "Ham-buk dwelling type" which was dominent in north-eastern Korea. In the era of gruop-immigration, various dwelling types were flew into Yen-Pien from southern Korea. In modern China, their southern types were changed into Yen-Pien type as similar as Ham-book type. After 1945, with the Great leap Forward and the Cultural Revolution, as communization of indivisual properties and reorganization of rural communities, each of dwellings became smaller and simpler in aspects of scales as well as functions. There are two types in Yen-Pien dwellings, those are 'single-file' and 'double-file' type. Three sub-types of latter arc 'six-bays', 'eight-bays', and rarely 'ten-bays'. The most common element of all types is Chong-ju-k'an; which is large room with heated floor, openig to kitchen. Now, modern dwellings of Korean immigrants are changing their spatial compositions, materials, and structures. With cultural assimilation as well as modernization, especially in urban areas, they are compelled to accept the elements of Chinese dwellings. But the spatial element of "Chong-ju-k'an", which is the core element of Yen-Pien dwelling type, never fade away nor is changed.