• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.1 s.232
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• pp.67-73
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• 2005

The paper presents a single-heater microfluid injector, whose ejected droplet volume is adjusted by digital current path control for a single microheater. The previous droplet volume adjustable methods have used the digital current control for multiple heaters or the analog current control for a single heater, while the present method uses the digital current control for a single microheater. Two different microinjectors, having a rectangular heater and a circular hearter, are designed and fabricated in the chip area of $7.64\;mm{\times}5.26\;mm$. The fabricated microinjectors have been tested and characterized for the number, size, shape and lifetime of the generated bubbles as well as for the volume and velocity of the ejected droplets. The input power for the rectangular heater and the circular heater has been varied in the ranges of $8.7{\sim}24.9{\mu}W\;and\;8.1{\sim}43.8{\mu}W$, respectively. The projected area of the generated bubble has been changed in the ranges of $440{\sim}l,3600{\mu}m^2\;and\;800{\sim}3,300{\mu}m^2$ for the rectangular heater and the circular heater, respectively. The microinjector with the rectangular heater ejects three discrete levels of the droplet in the volume range of $9.4{\sim}20.7pl$ with the velocity range of $0.8{\sim}1.7m/s$, while the microinjector with the circular heater achieves five discrete levels of the droplet in the volume range of $7.4{\sim}27.4pl$ with the velocity range of $0.5{\sim}2.8m/s$.

• Journal of Advanced Navigation Technology
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• v.20 no.5
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• pp.433-439
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• 2016

Several low-cost global navigation satellite system (GNSS) receivers do not support general range-domain correction, and DGNSS-CP (differential GNSS) method had been suggested to solve this problem. It improves its position accuracy by projecting range-domain corrections to the position-domain and then differentiating the stand-alone position by the projected correction. To project the range-domain correction, line-of-sight vectors from the receiver to each satellite should be calculated. The line-of-sight vectors can be obtained from GNSS broadcast ephemeris data or satellite direction information, and this paper shows positioning performance for the two methods. Stand-alone positioning result provided from Septentrio PolaRx4 Pro receiver was used to show the difference. The satellite direction information can reduce the computing load for the DGNSS-CP by 1/15, even though its root mean square(RMS) of position error is bigger than that of ephemeris data by 0.1m.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.4
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• pp.177-186
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• 2015

For data fusion of laser range finder (LRF) and vision camera, accurate calibration of external parameters which describe relative pose between two sensors is necessary. This paper proposes a new calibration method which can acquires more accurate external parameters between a LRF and a vision camera compared to other existing methods. The main motivation of the proposed method is that any corner data of a known 3D structure which is acquired by the LRF should be projected on a straight line in the camera image. To satisfy such constraint, we propose a 3D geometric model and a numerical solution to minimize the energy function of the model. In addition, we describe the implementation steps of the data acquisition of LRF and camera images which are necessary in accurate calibration results. In the experiment results, it is shown that the performance of the proposed method are better in terms of accuracy compared to other conventional methods.

• Journal of Advanced Navigation Technology
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• v.19 no.4
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• pp.278-287
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• 2015

The potential impact of aircraft emissions on the current and projected climate of our planet is one of the more important environmental issues facing the aviation industry. Increasing concern over the potential negative effects of greenhouse gas emissions has motivated the development of an aircraft emission estimation and prediction system as one of the ways to reduce aircraft emissions and mitigate the impact of aviation on climate. Hence, in this research, using Piano-X software which was developed by Lissys Co., fuel consumption and emissions for 3 types of aircraft were estimated for different design payloads with various flight distances and flight paths. Fuel burns for economy speed, long range cruise speed, maximum range speed were also investigated with various flight distances and altitudes.

• The Research Journal of the Costume Culture
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• v.20 no.6
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• pp.923-936
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• 2012

Apparel companies define their target customers to integrate consumers' needs into their product development processes. The sizing standards play a significant role in ready-to-wear garment business. Consumers' body build and sizes are different according to gender, age, and body type. The consumers' morphological feature of the one geographical area has changed with immigration, aging, and lifestyle change. In this study the way of defining body types in the standard garment sizing systems published in USA., UK, Germany, Japan, and Korea were compared. The results of this study show that most of the systems classified the body types by the index value. The chest-waist drop value was used for men's body type classification. Women's body types were defined by hip proportion. The hip-bust drop value was used for it. German and European garment sizing systems provide a wide range of men's body types. US men's garment sizes are developed for very conservative body type. US women's garment sizing system has had clearly defined women's body types. The Misses body types projected in the US garment sizing system had changed as women's waist girth got bigger compared to the past. In 2011 the US Misses sizes were divided into Curvy Misses size and Straight Misses size by the hip-waist drop value. The Curvy Misses sizes have smaller waist girth and larger hip girth than the Straight Misses sizes.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.72.1-72.1
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• 2013

Even though current microlensing follow-up observations focus on high-magnification events due to the high efficiency of planet detection, it is very difficult to do a confident detection of planets in high-magnification events with extremely weak central perturbations (i.e., the fractional deviation is ${\delta}{\leq}0.02$). For the confident detection of planets in the extremely weak central perturbation events, it is needed both the high cadence monitoring and the high photometric accuracy. A next-generation ground-based observation project, KMTNet (Korea Microlensing Telescope Network), satisfies both the conditions. Here we investigate how well planets in high-magnification events with extremely weak central perturbations are detected by KMTNet. First, we determine the probability of occurrence of events with ${\delta}{\leq}0.02$. From this, we find that for ${\leq}100M_E$ planets in the separation of $0.2AU{\leq}d{\leq}20AU$, events with ${\delta}{\leq}0.02$ occur with a frequency of more than 70%, in which d is the projected planet-star separation. Second, we estimate the efficiency of detecting planetary signals in the events with ${\delta}{\leq}0.02$ via KMTNet. We find that for main-sequence and subgiant source stars, ${\geq}1M_E$ planets can be detected more than 50% in a certain range that has the efficiency of ${\geq}10%$ and changes with the planet mass.

• International Journal of Control, Automation, and Systems
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• v.4 no.4
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• pp.438-447
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• 2006

Fuzzy controller's design depends mainly on the rule base and membership functions over the controller's input and output ranges. This paper presents two different approaches to deal with these design issues. A simple and efficient approach; namely, Fuzzy Subtractive Clustering is used to identify the rule base needed to realize Fuzzy PI and PD type controllers. This technique provides a mechanism to obtain the reduced rule set covering the whole input/output space as well as membership functions for each input variable. But it is found that some membership functions projected from different clusters have high degree of similarity. The number of membership functions of each input variable is then reduced using a similarity measure. In this paper, the fuzzy subtractive clustering approach is shown to reduce 49 rules to 8 rules and number of membership functions to 4 and 6 for input variables (error and change in error) maintaining almost the same level of performance. Simulation on a wide range of linear and nonlinear processes is carried out and results are compared with fuzzy PI and PD type controllers without clustering in terms of several performance measures such as peak overshoot, settling time, rise time, integral absolute error (IAE) and integral-of-time multiplied absolute error (ITAE) and in each case the proposed schemes shows an identical performance.

• Journal of the Korean earth science society
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• v.23 no.2
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• pp.119-131
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• 2002

Constructivism is defined in a variety of ways (e.g., constructivist research paradigm, sociological constructivism, and philosophical constructivism) and applied in vastly different contexts. Among the various usages and interpretations of constructivism, one is educational constructivism that embodies an epistemological view of knowledge and learning that is an alternative to naive empiricism or classical behaviorism. To represent the full range of stances taken by educational constructivists, three versions of educational constructivism were considered in this study: individual constructivism originating in the work of Piaget, the radical version of constructivism associated with von Glasersfeld, and the social constructivism of Vygotsky. I investigated preservice teachers' meaning construction about constructivist epistemology as they went through their preservice teacher education program using in-depth interviews. This preservice teacher education program employs constructivist aspects of teacher education and generates applications of constructivism to the practice of teaching. Features of preservice teachers' internalized meanings of educational constructivism include: (1)traditional pedagogy as the default, (2) Literal interpretation of constructivism, (3) Individual constructivism as conceptual change learning, (4) Radical constructivism as a strong individualistic philosophy, (5) Social constructivism as being too ideal to be practical. A compilation of the teachers' own statements about how to implement conceptual change learning and their projected role as constructivist teacher is also provided.

• Journal of the Korean Society of Costume
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• v.22
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• pp.333-344
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• 1994

In this study an experiment was made using the function of computer simulation os to whether the phenomenon of optical illusion takes place also in clothing on the human body three-dimensional space through the case study of the Gestalt illusion of planar con-traction and expension by amodal completion in perceptual organization. One woman of latter 30s was selected as the experimental subject. She was made to wear the experimental clothing and then the frontal picture was projected of in the experimental clothing which was scanned into the com-puter. For the sake of the contractive experiment 5 stages were divided by 5-15cm the thick-nes of the black vertical line in the center of the upper garmet as the variable and for the sake of the expansive experiment the skirt length was set as the variable. It length measured 50-90cm which was divided by 10cm into 5 stages and simulated using the CAD. The basic design and the experimental de-sign were made one pair and the pictures totalled 20 pictures such as ten pictures save the human body for the estimation of the up-per garmet alone and ten pictures for the ob-servation of the effect on the human body. The extimating panel consisting of 20 panellers estimated contraction/expansion in the estimation of the upper garmet and the tall effect/the slim effect in the estimation of optical illusion as the estimating factors on the 9-point scale. All the date from experiment were analyzed by ANOVA(analysis of variance) and DUNCAN'S multiple range. As a result the experimental designs all showed a significant optical illusion in comparision with the basic design.

• International Journal of Costume and Fashion
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• v.7 no.2
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• pp.49-63
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• 2007

In this study, we inquire into the general concepts of eroticism as it appears in literature and the arts, and use this as a foundation to meditate on the eroticism of attire throughout history. We also ascertained external forms based on the range of "The way we look" by Delong. In this way we inclusively studied both the content and form of modes of eroticism in the perspective of Brodsky's "linked solution." The original concept of eroticism is a technique by which one attains physical passion, referring to a nature which is deeply rooted in the cultural traditions, myths, habits. religion and arts of mankind, inducing expressions of sensual love. We integrated this eroticism in 4 categories: sensuality, which induces beauty; naturality, denoting idealization or rational beauty; primitivity, characterized by grotesque expressions or direct and natural sexual depictions; and symbolism by which sex is symbolically or mechanically projected. The concept of eroticism contains both positive and negative aspects, but rather than dealing with sex in a mechanical or perverted manner to express eroticism, it is more appropriate to guide the direction of modes of eroticism by stimulating the "desire to show" and the "desire to see" with the dialectic of obstruction and exposure as a figurative expression of true passion, and narcistic phenomena in which beauty is expressed through exaggeration or magnification and adhesion.