• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.114-117
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• 2005

Air cleaners in all of the automotive engines have been used for decades. In the early 1920's the oil bath type was the popular shape of air cleaners. The air cleaners of the oil wetted bath type were introduced in 1940's. The shape of the dry pleated paper type media was introduced in the 1950's. This trend still continues with new and innovative media being introduced. Engine air cleaners should have effectively removed and reduced harmful contaminants being ingested into engines. This studies show that both, the ingested contaminant size and concentration need to be controlled. This paper com pare and analyze the characteristics over the economics, engine performances and reduction of noises of power-plus air filters with wet paper which were sticked to heavy duty diesel engine.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1983.10a
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• pp.68-72
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• 1983

The Hadamard matrix is a symmetric matrix made of plus and minus ones as entries. There fore the use of Hadamard transform in the image processing requires only the real number operations and results in the computational advantages. Recently, However, certain degradation aspects have been reported. In this paper we propose a WH matrix which retains the main properties of Hadamard matrix. The actual improvement of the image transmission in the inner part of the picture has been demonstrated by the computer simulated image developments. The orthogonal transform offers a useful facility in the digital signal processing. As the size of the transmission block increases, however, the assigment of bits for each data must increase exponentially. Thus the SNR of the image tends to decline accordingly. As an attempt to increase the SNR, we propose the WH matrix whose elements are made of $\pm$1, $\pm$2, $\pm$3, and the unitform is 8$\times$8 matrix.

• The Journal of the Korean dental association
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• v.55 no.7
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• pp.468-480
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• 2017

A wide variety of benign and malignant lesions and other diseases can develop on oral mucosa. Oral mucosal lesions can also be associated with an underlying systemic disease, so their correct diagnosis, which may even share similar clinical and demographic features, is always a challenge for a dentist. Common oral mucosal lesions include candidiasis, herpes viral infection, leukoplakia, recurrent aphthous stomatitis, pemphigus, lichen planus and benign migratory glossitis. The differential diagnosis of these lesions are based on a thorough review of the patient's past medical and dental history and a complete oral examination. The knowledge of clinical features such as size, location, morphology, color, and pain is helpful in establishing a diagnosis. In addition, diagnostic tests, including microbiologic and laboratory tests and biopsies are usually required for establishing a proper diagnosis.

• Journal of Integrative Natural Science
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• v.9 no.3
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• pp.171-176
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• 2016

Rap1 is a key regulator of cell adhesion and migration. Although increasing evidence indicates that the Rap1 signaling pathway is involved in the process of bone remodeling, the mechanism by which Rap1 regulates osteoblastic differentiation and cell adhesion remains unknown. Here, we investigated the morphological characteristics and osteoblastic differentiation of cells expressing constitutively activated form of Rap1A (Rap1ACA) or Rap1 GTPase activating protein Rap1GAP and found that activated Rap1 induces osteoblastic differentiation and cell adhesion as well as cell spreading. When osteoblastic differentiation was induced, Rap1ACA cells showed considerably higher levels of calcium deposits than the wild-type and Rap1GAP-overexpressing cells did. Rap1ACA cells showed increased spreading and size, as well as strong cell adhesion and significantly decreased growth rates. F-actin staining using phalloidin revealed several thin thread-like filopodia around the protrusions in Rap1ACA cells, which possibly contribute to the increased cell adhesion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.189-190
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• 2017

As buildings take on more advanced features, mechanical facilities of buildings are accounting for increasingly greater significance in building construction projects. However, mechanical facility designers are forced to be content with design service fees that do not properly compensate their excessive workload, with lowest-bid-first tendering practices compounding their economic woes. In relation to this, this Study aims to offer suggestions for better standards for compensation of design service for mechanical facilities of buildings, highlighting five key suggestions in consideration of relatively small size of work and unmatched long duration of work.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.457-458
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• 2007

We investigated a resistor network model for the horizontal AlInGaN LED. Adding the proposed current density dependent relative quantum efficiency, the power simulation can be also obtained. Comparing the simulation and the measurement results for the LED with the size of $350{\mu}m$, the model is reasonable to simulate the forward voltage and the light output power. Using this model we investigated the optimization of the position and the number of the finger electrodes in a given chip area. It shows that the center disposition of the p-finger electrode in p-area is optimal for the voltage and best for the power. And the minimum number of the n-finger electrodes is best for the power.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.9
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• pp.1596-1612
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• 2011

Coordinated Multi-Point (CoMP) transmission / reception is being studied in Long Term Evolution-Advanced (LTE-A) for future evolution of the $3^{rd}$ Generation Partnership Project (3GPP) LTE. Support of soft handover is essential for improving the performance of cell edge users. CoMP provides a natural framework for enabling soft handover in the LTE system. This paper evaluates the soft handover gain in LTE-A downlink. Mathematical analysis of signal to interference plus noise ratio (SINR) gain and the handover margins for soft handover and hard handover are derived. CoMP system model is developed and an inter-cell and intra-cell interference model is derived, taking into account the pathloss, shadowing, cell loading, and traffic activity. Reference signal received power (RSRP) is used to define the triggers and the measurements for soft handover. Our results indicate that parameter choices such as handover margin and the CoMP set size impact CoMP performance gain.

• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2523-2533
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• 2021

In the last decade, the best estimate plus uncertainty methodologies in nuclear technology and nuclear power plant design have become a trending topic in the nuclear field. Since BEPU was allowed for licensing purposes by the most important regulator bodies, different uncertainty assessment methods have become popular, overall non-parametric methods. While non-parametric tolerance regions can be well stated and used in uncertainty quantification for licensing purposes, the propagation of the uncertainty through different codes (multi-scale, multiphysics) in cascade needs a better depiction of uncertainty than the one provided by the tolerance regions or a probability distribution. An alternative method based on the parametric or distributional probability boxes is used to perform uncertainty quantification and propagation regarding statistic uncertainty from one code to another. This method is sample-size independent and allows well-defined tolerance intervals for uncertainty quantification, manageable for uncertainty propagation. This work characterizes the distributional p-boxes behavior on uncertainty quantification and uncertainty propagation through nested random sampling.

• The Journal of Korea Robotics Society
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• v.17 no.3
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• pp.359-364
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• 2022

This study presents a nonlinear model predictive control (NMPC)-based obstacle avoidance and whole-body motion planning method for the mobile manipulators. For the whole-body motion control, the mobile manipulator with an omnidirectional mobile base was modeled as a nine degrees-of-freedom (DoFs) serial open chain with the PPR (base) plus 6R (arm) joints, and a swept sphere volume (SSV) was applied to define a convex hull for collision avoidance. The proposed receding horizon control scheme can generate a trajectory to track the end-effector pose while avoiding the self-collision and obstacle in the task space. The proposed method could be calculated using an interior-point (IP) method solver with 100[ms] sampling time and ten samples of horizon size, and the validation of the method was conducted in the environment of Pybullet simulation.

• Korean Journal of Animal Reproduction
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• v.14 no.1
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• pp.84-91
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• 1990

Experiments were disigned to define and optimize efficiency of a system whereby pig follicular oocytes could be matured and fertil ized in vitro. The pig oocytes removed from 1- 2 mm and 3-7 mm follicles were cultured in vitro in the mKRB(-BSA) solution containing estrous sow serum (ESS), FCS or dialyzed pig follicular fluid for 24 to 48 hr at 37$^{\circ}C$. The oocytes matured in vitro were evaluated after epididymal spermatozoa-oocyte incubation for 24 hr for pronucleus formation. 50-60% of the oocytes reached metaphase II during 36 to 48 hr of culture. There was no differernce in oocyte matura¬tion between two groups of follicular size but meiosis was slightly faster in the 3-7 mm follicular oocytes. The oocytes matured in mKRB (-BSA) plus 5% ESS, 15% FCS or dialyzed follicular fraction showed slightly higher maturation rates than the control mKRB. in vitro fertilization, pronucleus formation, tended to be increased when mKRBi-BSA) plus 5% ESS or 15% FCS was used for oocyte maturation and in vivo -capacitated spermatozoa were inseminated, respectively. It is concluded that ESS, FCS and dialyzed pig follicular fluid may be effective factors for in vitro maturation and fertilization of pig follicular oocytes.