• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.514-517
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• 2005

Microstereolithography(MSL) has evolved from the stereolithography technique, and is also based on a light-induced layer-stacking fabrication. Although integral MSL allows the manufacture of a complete layer by one irradiation only, there is a problem related with shape precision due to the light-intensity distribution of focused image. In this study, we developed the integral MSL apparatus using Digital Micromirror Device ($DMD^{TM})$, Texas Instruments) as dynamic pattern generator. It is composed of Xenon-Mecury lamp, optical devices, pattern generator, precision stage, controllers and the control program. Also, we have studied curing depth and width of photocurable resin according to the change of exposure energy.

• Korean Journal of Remote Sensing
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• v.23 no.3
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• pp.199-209
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• 2007

Traditionally, aerial images have been used as main sources for compiling topographic maps. In recent years, lidar data has been exploited as another type of mapping data. Regarding their performances, aerial imagery has the ability to delineate object boundaries but omits much of these boundaries during feature extraction. Lidar provides direct information about heights of object surfaces but have limitations with respect to boundary localization. Considering the characteristics of the sensors, this paper proposes an approach to extracting buildings from lidar and aerial imagery, which is based on the complementary characteristics of optical and range sensors. For detecting building regions, relationships among elevation contours are represented into directional graphs and searched for the contours corresponding to external boundaries of buildings. For generating building models, a wing model is proposed to assemble roof surface patches into a complete building model. Then, building models are projected and checked with features in aerial images. Experimental results show that the proposed approach provides an efficient and accurate way to extract building models.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.533-540
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• 2022

Because of the massive development of nuclear power plants in China in recent years, China is facing the challenge of radioactive waste disposal. China has established complete regulatory requirements for radioactive waste disposal, but it also has encountered problems and challenges in low-level radioactive waste disposal in terms of management, selection of disposal facility sites, and implementation of a site selection plan. Three low-level radioactive waste disposal facilities that have been operated in China are described, and their activity limits, locations, and capacities are also outlined. The connotations of "regional" and "centralized" disposal policies are discussed in light of the characteristics of the radioactive waste. The characteristics and advantages of the regional and centralized disposal policies are compared. It is concluded that the regional disposal policy adopted in 1992 can no longer meet the current disposal needs, and China should adopt a combination of the two disposal policies to solve the problem of radioactive waste disposal.

• Progress in Superconductivity
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• v.3 no.1
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• pp.1-4
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• 2001

Interface-engineered junctions with $YbBa_2$$Cu_3$$O_{7}$ as the counter electrode were demonstrated. The junctions exhibited excellent Josephson characteristics with a Josephson critical current ($I_{c}$) ranging from 0.1 mA to 8 mA and a magnetic field modulation of the $I_{c}$ exceeding 80% at 4.2 K while maintaining complete c-axis orientation of the counter-electrode layer. The$ 1\sigma$ spreads in $I_{c}$ for junctions with an average $I_{c}$ of 1-2 mA were 5-8% for 16 junctions within a chip, and 9.3% for a 100-junction array. Our dI/dV measurements suggest that a theoretical approach taking into account both a highly transparent barrier and the proximity effect is required to fully understand the Junction characteristics.ristics.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.3
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• pp.323-330
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• 2007

Purpose: The purpose of this study was to assess the difference in knowledge and learning needs of the coronary artery disease according to the general characteristics of the patients with type 2 diabetes mellitus. Method: The participants were 188 patients who had diabetes mellitus. Data were obtained between January and April 2006 by asking the knowledge and learning needs of the coronary artery disease. Data were analyzed using SAS program. Results: Participants' knowledge level was high in the cause and prevention, but the level was low in the symptom and occurrence of pain. Learning need for "Influence of smoking on heart disease" and "The structure and functions of the heart" was great, but learning need for "Complete diagnosis" and "Management of pain and pressure on the sternum" was little. No significant differences were found in the knowledge level of the coronary artery disease according to the general characteristics. Learning needs were greater in participants under 60 years of age (p=0.011) and in those with low education level (p=0.049). There was a significant correlation between knowledge and learning needs of the coronary artery disease (p=0.003). Conclusion: In planing the education programs, the general characteristics of the patients should be considered.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.811-818
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• 2017

Objective: This experiment was conducted to investigate the effects of fungal treated oil palm fronds (FTOPF) on performance, carcass traits, meat quality, and muscle chemical composition. Methods: Eighteen growing crossbred male goats (Thai Native${\times}$Anglo Nubian) with $18.7{\pm}2.0kg$ of initial body weight (BW) were stratified and blocked by BW in a randomized complete block design. Three diets containing 30% of oil palm fronds (OPF) either untreated (UOPF) or treated with Lentinussajor-caju (FTOPF) with or without urea (FTOPFU) were used as roughage sources in total mixed rations (TMRs). The diets were offered ad libitum and weight gain was determined. At the end of the experimental period, the harvest data and carcass characteristics of the goats were recorded, and muscular longissimus dorsi composition was determined. Results: No significant effect of fungal treated (FT) inclusion was observed in any of the feed intake, growth performance, and carcass characteristics. Likewise, no apparent effects on carcass composition and muscle chemical composition were detected in this study, except for hind leg and chump were affected (p<0.05) by FT inclusion. Conclusion: In conclusion, feeding of fungal (Lentinussajor-caju) treated oil palm frond in TMR diet did not affect performance and carcass characteristics in finishing goats.

• Journal of ILASS-Korea
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• v.10 no.1
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• pp.17-23
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• 2005

Even though a relatively complete knowledge base has been established for diesel sprays, much of the knowledge cannot be directly translated to correlate the characteristics of gasoline spray. The macroscopic characteristics of gasoline impingement spray was investigated with photographic and image processing technique by Particle Motion Analysis System. The injector with single hole nozzle diameter of 0.28 mm was used in this experiment and the injection duration was selected as 10 msec. The injection pressure with 0.3, 0.35, and 0.4 MPa, impingement distance or 70, 100 and 130m, impingement angle or 0.15, 30 and $45^{\circ}$ were employed for the variables to affect the spray characteristics of impinging spray. It is clear that there is the analogy on the spray tip penetration between the gasoline impinging jet and diesel free jet. The spray tip penetration of impinging gasoline spray is proportional to the quarter power of the time after start of injection. The maximum height of impinging gasoline spray is also proportional to the quarter power of the time regardless of impingement distance, impingement angle and injection pressure. In addition, the effect of impingement angle on the spray tip penetration is significant according to the time after start of injection, even though there is minor effect in the initial stage of time after start of injection. Moreover, there is no remarkable effect of injection pressure on the spray tip Penetration under the experimental condition used in this study.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.4
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• pp.28-33
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• 2005

Recently, trends of TFT-LCD toward larger scale and thinner thickness continue. so, demands of Light Guide Panel (LGP) which is to substitute for prism sheet are appeared. Functions of LGP obtaining polarization of light of the prism sheet as well as the incidence and reflection of light are demanded. This prism type LGP to complete functions of the existing LGP and polarization at once must be supported by micro machining technology of LGP surface. In this research, the machining characteristics of the various materials were analysed by shaping using V-shaped single crystal diamond tool. The characteristics are machined surface, machining force due to the variation of cutting depth. Used specimens are engineering materials, which are 6:4 brass, oxygen-free copper, Al6061, PC, PMMA. The FFT analysis of the measured cutting force was conducted. The cutting characteristics were analyzed and the optimum cutting conditions with materials were established.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.159-169
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• 1998

The purpose of this study is to analyze the radiation characteristics of the shaped Cassegrainian antenna. Radiation pattern of the sub-reflector is calculated by GTD (Geometrical Theory of Diffraction) The complete radiation patterns are obtained by summing the reflect field from the surface and the diffracted fields from the edge. The first and the second derivative on the sub-reflector are calculated by the local interpolation technique. The Radiation characteristics of the main-reflector are obtained by integrating the surface current density, which is derived from PO approximation. The radiation integral is expanded by the Jacobi-Bessel series for the purpose of reducing the computation time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.2840-2861
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• 2020

The purpose of this survey-based study is to make an analysis of search engine users' behaviors on the Search Engine Results Pages (SERPs) based on the three demographic characteristics gender, age, and program studying. In this study, a questionnaire was designed with 12 closed-ended questions. Remaining questions other than the demographic characteristic related ones were about "tab", "advertisement", "spelling suggestion", "related query suggestion", "instant search suggestion", "video result", "image result", "pagination" and the amount of clicking results. The questionnaire was used and the data collected were analyzed with the descriptive statistics as well as the inferential statistics. 84.2% of the study population was reached. Some of the major results are as follows: Most of each demographic characteristic category (i.e. female, male, under-20, 20-24, above-24, English computer engineering, Turkish computer engineering, software engineering) have rarely or more click for tab, spelling suggestion, related query suggestion, instant search suggestion, video result, image result, and pagination. More than 50.0% of female category click advertisement rarely; however, for the others, 50.0% or more never click advertisement. For every demographic characteristic category, between 78.0% and 85.4% click 10 or fewer results. This study would be the first attempt with its complete content and design. Search engine providers and researchers would gain knowledge to user behaviors about the usage of the SERPs based on the demographic characteristics.