• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.243-248
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• 2002

As a notion of environment protection changes throughout the world, construction engineers, as part of the effort to resolve environmental problems, have been actively doing research on environmental friendly porous concrete using large and non-uniform aggregate. Porous Concrete enables water and air to pass through a firmly hardened material and allows required nutrients to reach roots of plants. The purpose of this study is to analyze planting ability when the change of aggregate gradation and void ratio. The results of an experiment from the planting ability of the porous concrete to its influence on the compressive strength are reported in this paper. As a result of the experiment, the compressive strength is higher when the gradation of aggregate is smaller, and it also goes higher when the void ratio gets smaller The planting ability of porous concrete is decided by the germination and the grass length of Indigofera pseudo-tinctoria(IPT). The length of IPT is longer when the gradation of aggregate is greater and the void ratio gets smaller.

• Journal of Interdisciplinary Genomics
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• v.2 no.2
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• pp.20-25
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• 2020

Mucopolysaccharidosis type III (MPS III or Sanfilippo syndrome) is a multisystem lysosomal storage disease that is inherited in an autosomal recessive manner. It consists of four subtypes (MPS IIIA, B, C, and D), each characterized by the deficiency of different enzymes that catalyze the metabolism of the glycosaminoglycan heparan sulfate at the lysosomal level. The typical clinical manifestation of MPS III includes progressive central nervous system (CNS) degeneration with accompanying systemic manifestations. Disease onset is typically before the age of ten years and death usually occurs in the second or third decade due to neurological regression or respiratory tract infections. However, there is currently no treatment for CNS symptoms in patients with MPS III. Invasive and non-invasive techniques that allow drugs to pass through the blood brain barrier and reach the CNS are being tested and have proven effective. In addition, the application of genistein treatment as a substrate reduction therapy is in progress.

• ETRI Journal
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• v.31 no.5
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• pp.585-592
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• 2009

This paper presents a method for decoding high minimal distance ($d_{min}$) short codes, termed Cortex codes. These codes are systematic block codes of rate 1/2 and can have higher$d_{min}$ than turbo codes. Despite this characteristic, these codes have been impossible to decode with good performance because, to reach high $d_{min}$, several encoding stages are connected through interleavers. This generates a large number of hidden variables and increases the complexity of the scheduling and initialization. However, the structure of the encoder is well suited for analog decoding. A proof-of-concept Cortex decoder for the (8, 4, 4) Hamming code is implemented in subthreshold 0.25-${\mu}m$ CMOS. It outperforms an equivalent LDPC-like decoder by 1 dB at BER=$10^{-5}$ and is 44 percent smaller and consumes 28 percent less energy per decoded bit.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.2
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• pp.115-120
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• 1996

In this paper, a sliding mode controller which is characterized by high accuracy, fast response and robustness is applied to speed control of AC-SERVO motor. The control input is changed to the continuous one in the boundary layer to reduce the chattering phenomenon, and the boundary layer converges to zero when the state variables of system reach to steady state values. The integral compensator is added to reduce steady state error and to provide the continuous torque reference. The acceleration which is necessary for the sliding plane is estimated by an obsever. Sliding surface is included in control input to enhance the robustness and transient response without increasing sliding mode controller gain. The proposed controller is implemented by DSP(digital signal processor). The effectiveness of the proposed scheme is demonstrated through experimental works.

• Journal of Agricultural Extension & Community Development
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• v.16 no.4
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• pp.837-867
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• 2009

The purpose of this study is evaluate the direct payment program for rural landscape conservation and deduce facts to improve. This research is composed with a survey on local government officials and farmers joined this program, and used monitering in selected 41 zones. According to the surveys, this program showed a positive contribution to the effects: village harmony, visitors increase, village income. However, It's contribute in short term objectives, but has not yet reach the ultimate goal such as regional development through visitors and village income. We found some problems in the monitering, on the agreement with farmers, range of village activities, operating AgriX program, etc. Finally, we suggest some proposals ; 1) to redefine the aims and range for the program, 2) to clarify a village action program, 3) to strength the admission procedure, 4) to designate district based on landscape resources survey.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.7
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• pp.601-606
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• 2016

In this paper, an energy harvester is developed that has advantages regarding piezoelectric noise minimization, mass production, and an easily available environmental energy source, electromagnetic induction, as well as low-frequency bandwidth and high amplitude. A process for fabricating a three-dimensional multilayered planar coil using micro-electro-mechanical systems (MEMS) on a flexible printed circuit board FPCB is introduced. Optimal shape and size were calculated via internal resistance and inductance, and a prototype was fabricated through the MEMS procedure while considering the possibility of mass production. Although the internal resistance matched the designed value, the electromotive force generated did not reach the intended amount. The main reason for the decrease in efficiency was the low area of coil outskirt exposed to the magnetic field while there was relative motion between the magnet and the coil.

• Proceedings of the KOR-KST Conference
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• 1996.06a
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• pp.3-22
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• 1996

To translate the goal of redeveloping Shanghai as one of the international hubs of economy, finance and trade in 2010, the foundation is to be created, and international standing as global city is to be established preliminarily. Transformation of urban functions and approach of "High starting position and jump over" will give impetus to promote Shanghai as an international metropolitan within fairy short period of time. To transform urban functions and translate" High starting position and jump over", certain links which have great impact on Shanghai's rising-up must be handled and normal approach to develop the city must be renovated to reach the goal of establishing an international city. Four strategic approaches as following are explored in this paper : $\bullet$ To transform urban function from industry only to integrated developments. $\bullet$ To break through administrative boundary and expand urban development space. $\bullet$ To develop centralized urban infrastructure framework. $\bullet$ And to erect modern life and culture facilities towards 21st century.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.36-38
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• 2001

A basic structure of 2500V-4500V reverse-conducting GCT (RC-GCT) is given in this paper. The punch-through type (PT) is adopted for narrow N-base with high resistivity so that the fast turn-off and low on-state voltage can be achieved. The photo mask design was made upon the both turn-off performance and solution of separation between GCT and integrated freewheeling diode (FWD) part. The turn-on and turn-off characteristics for reserve-conducting gate commutated thyristors (RC-GCTs) were investigated by ISE simulation. Additionally, the local carrier lifetime control by proton irradiation was adopted so as not only to obtain the reduction of turn-off losses of GCT but also to reach a soft reverse recovering characteristics of FWD

• Journal of Information Technology Applications and Management
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• v.22 no.3
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• pp.19-33
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• 2015

SNS is perceived as an effective tool for sharing news and enabling news content to reach many more users than before. And some users think that SNS is an important source to get news. This study's purpose is to understand the key factors contributing to behavior of news consumption on social network sites in Cambodia and its influence. We identified three key factors including convenience, recency, and variety; however, recency showed less significant effect on news consumption on SNS. Besides the key factors, it also seeks to understand the impact of news consumption on social engagement and government's transparency in Cambodia. The analytical results achieved through the Partial Least Squares (PLS) approach.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.112-118
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• 2002

Injection molding process factors such as molding temperature, injection pressure, flow rate and flow velocity, must be controlled properly in filling and packing phases in the injection molding process. In this study, effects of these factors on the injection molding were investigated through the flow analysis fur the filling and packing phases. Molding troubles like flow mark, weld line, sink mark, short shot and warpage can be caused by these injection molding process factors. Among them, the short shot was caused by that the packing pressure could not reach properly to the filling end part in the packing phase and hence the flow rate could not be supplied to the full. In addition, as the flow rate for the volumetric shrinkage during the frozen phase could not be supplied properly by the packing pressure, the short shot appeared. Here, the volumetric shrinkage reduced with increasing the packing pressure and also the warpage of molded part increased with increasing the packing pressure.