• Clinical and Experimental Pediatrics
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• v.56 no.4
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• pp.159-164
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• 2013

Purpose: Indoxyl sulfate and p-cresyl sulfate are important protein-bound uremic retention solutes whose levels can be partially reduced by renal replacement therapy. These solutes originate from intestinal bacterial protein fermentation and are associated with cardiovascular outcomes and chronic kidney disease progression. The aims of this study were to investigate the levels of indoxyl sulfate and p-cresyl sulfate as well as the effect of probiotics on reducing the levels of uremic toxins in pediatric patients on dialysis. Methods: We enrolled 20 pediatric patients undergoing chronic dialysis; 16 patients completed the study. The patients underwent a 12-week regimen of VSL#3, a high-concentration probiotic preparation, and the serum levels of indoxyl sulfate and p-cresyl sulfate were measured before treatment and at 4, 8, and 12 weeks after the regimen by using fluorescence liquid chromatography. To assess the normal range of indoxyl sulfate and p-cresyl sulfate we enrolled the 16 children with normal glomerular filtration rate who had visited an outpatient clinic for asymptomatic microscopic hematuria that had been detected by a school screening in August 2011. Results: The baseline serum levels of indoxyl sulfate and p-cresyl sulfate in the patients on chronic dialysis were significantly higher than those in the children with microscopic hematuria. The baseline serum levels of p-cresyl sulfate in the peritoneal dialysis group were significantly higher than those in the hemodialysis group. There were no significant changes in the levels of these uremic solutes after 12-week VSL#3 treatment in the patients on chronic dialysis. Conclusion: The levels of the uremic toxins p-cresyl sulfate and indoxyl sulfate are highly elevated in pediatric patients on dialysis, but there was no significant effect by probiotics on the reduction of uremic toxins in pediatric dialysis patients. Therefore, studies for other medical intervention to reduce uremic toxins are also necessary in pediatric patients on dialysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.282-286
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• 2017

Rapid industrialization and urbanization have resulted in an increase in impervious areas and an increase in runoff, therefore, this causes more flooding and damage in urban areas. This study has analyzed the effects of improvements to the roughness coefficient in storm sewer pipes on flood runoff and outflow through rainfall-runoff simulations. The simulations are implemented by three scenarios to evaluate effects of improvements to the roughness coefficient for the improved length ratio to the total length, diameters and mainlines of sewer pipes. The size and length of the sewer mains are large and long to effectively increase the flow rate to the outlet, secure the passage discharge capacity of the pipe and reduce the overflow. It is effective for flood reduction that the improvement to roughness coefficient is first conducted in mainlines with longer lengths and larger diameters. The results from this study can provide a guideline for prioritizing of the sewer pipe replacement.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.2
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• pp.132-138
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• 2012

An 8-week feeding experiment was conducted to evaluate three types of squid Sepia esculenta liver powder (SLP) as a dietary protein source replacing fish meal (FM) in juvenile olive flounder Paralichthys olivaceus. To replace FM, six experimental diets were formulated with three types (A, B, C) of SLP at the 5 and 10%: SLP-A5, SLP-A10, SLP-B5, SLP-B10, SLP-C5, and SLP-C10. One control diet contained 100% FM as the main protein source and another was a commercial diet (Com). Fish with an average body weight of $22.8{\pm}0.4$ g ($mean{\pm}SD$) were allocated randomly to aquaria in groups of 20 fish and fed the experimental diets in triplicate to satiation. The weight gain (WG) and specific growth rate (SGR) of fish fed the SLP-C10 diet were lower than those of fish fed the FM and SLP-B5 diets. No significant difference was observed in the WG and SGR among fish fed the diets other than SLP-C10. The feed efficiency (FE) and protein efficiency ratio (PER) of fish fed each SLP diet did not differ from those fed the control diet. However, fish fed SLP-C5 and SLP-C10 had a lower FE and PER than the fish fed commercial, SLP-A5 and SLP-B5 diets. Each SLP diet except for SLP-C10 could replace up to 10% of FM for juvenile olive flounder. The results of this experiment provide information that will assist in formulating an inexpensive practical diet containing SLP for juvenile olive flounder.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4658-4664
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• 2013

This paper presents the effects of the tube materials on the heat transfer performance of double-tube heat exchangers for the development of heat exchangers using deep sea water. Heat exchangers made of titanium, aluminum. stainless steel, iron, copper, and aluminum with carbon black 0.015mm and 0.15mm coating were tested. Also, the heat transfer rate of each heat exchanger was calculated by using EES program. The calculated values were compared with the experimental ones, and the deviations were less than 10%. From the above experiment and analysis, aluminum with carbon black 15 coating can be considered the most promising candidate for the replacement of titanium heat exchanger.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.311-314
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• 1996

Eighteen patients (13 female and ave male) aged from 15 to 62 years (mean age 42.6 years) underwent excision of cardiac myxoma(17 left atrial, one right atrial) between 1985 and 1994 at Pusan National University hospital. All patients complained of exertional dyspnea and most had a few additional symtoms including palpitation, chest pain, syncope, general weakness, weight loss, fever, cough and epigastric disconyort. The diagnosis was made by echocardiography alone in left atrial myxomas but a myxoma in right atrium was diagnosed incidentally during mitral valve replacement for rheumatic valvular heart disease. The tumor attachment sites were fossa ovalis in 13, other interatrial septum in 4, mitral valve annulus in one and free wall of left atrium in two cases. The tumor was excised successfully via right atriotomy in 8 and biatriotomy in 10 cases. There was no hospital nor late death, and no recurrent case during the follow up period. Curative surgical excision of cardiac myxoma can be performed with low morbidity and very low r currence rate.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.6
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• pp.749-756
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• 2015

In this paper, we propose a unique systolic structure and communication algorithm that maintains a solid link between nodes using synchronous digital communication and enables low power communication. This system was designed by using CC2500 RF transceiver, CC2590 RF front end and C8051F330 low power microcontroller. The measurement of power consumption in the network link shows below $400{\mu}W$ in data transfer rate 320bps. The system constitutes the base unit of low power wireless network that was composed of each seven link nodes having eight sensor nodes. Results of the experiments show that link nodes using a 4Ah battery could operate over 3 years without replacement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.727-736
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• 2009

In this paper, the $arccos(cos^{-1})$ arithmetic unit for mobile graphics accelerator is designed. The mobile vector graphics applications need tight area, execution time, power dissipation, and accuracy constraints compared to desktop PC applications. The designed processor adopts 2nd-order polynomial approximation scheme based on IEEE floating point data format to satisfy speed and accuracy conditions and reduces area via hardware sharing structure. The arccosine processor consists of 15,280 gates and its estimated operating frequency is about 125Mhz at operating condition of $0.35{\mu}m$ CMOS technology. Because the processor can execute arccosine function within 7 clock cycles, it has about 17 MOPS(million arccos operations per second) execution rate and can be applicable to mobile OpenVG processor. And because of its flexible architecture, it can be applicable to the various transcendental functions such as exponential, trigonometric and logarithmic functions via replacement of ROM and minor hardware modification.

• IEMEK Journal of Embedded Systems and Applications
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• v.4 no.4
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• pp.180-189
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• 2009

Currently, most automobile companies are interested in research on intelligent autonomous vehicle. They are mainly focused on driver's intelligent assistant and driver replacement. In order to develop an autonomous vehicle, lateral and longitudinal control is necessary. This paper presents a lateral and longitudinal control system for autonomous vehicle that has only mono-vision camera. For lane detection, we present a new lane detection algorithm using clothoid parabolic road model. The proposed algorithm in compared with three other methods such as virtual line method, gradient method and hough transform method, in terms of lane detection ratio. For adaptive control, we apply a vanishing point estimation to fuzzy control. In order to improve handling and stability of the vehicle, the modeling errors between steering angle and predicted vanishing point are controlled to be minimized. So, we established a fuzzy rule of membership functions of inputs (vanishing point and differential vanishing point) and output (steering angle). For simulation, we developed 1/8 size robot (equipped with mono-vision system) of the actual vehicle and tested it in the athletics track of 400 meter. Through the test, we prove that our proposed method outperforms 98 % in terms of detection rate in normal condition. Compared with virtual line method, gradient method and hough transform method, our method also has good performance in the case of clear, fog and rain weather.

• Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.305-310
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• 2009

This study was carried out to evaluate the use of fermented skipjack tuna viscera (FSTV) as an alternative for fish meal in juvenile olive flounder (Paralichthys olivaceus) diets. Lactobacillus bulgaricus was used as a starter for fermentation of skipjack tuna viscera. Four isonitrogenous (49% crude protein) and isocaloric (4 kcal/g DM) diets were formulated to contain graded levels (0, 5, 10, and 15%) of FSTV. Each experimental diet was fed three replicate groups (40 fish per tank) of juvenile flounder (average weight, $3.3\pm0.2$ g) for 5 weeks. At the end of feeding experiment, inclusion of FSTV up to 15% in diets did not affect survival rate (%) and weight gain of fish. Feed efficiency, protein efficiency ratio, protein and lipid retentions of fish fed the diet containing 10% FSTV were higher than those of fish fed the control diet (P<0.05). The values of fish fed the diet containing 15% FSTV were not different from those of fish fed other diets. Whole body lipid content of fish fed the diet containing 10% FSTV was higher than that of fish fed the diet containing 15% FSTV and control diet. The present results indicate that fermented skipjack tuna viscera could partially replace fish meal in juvenile flounder feed, and the inclusion of 10% FSTV may be efficient in improving the feed utilization of fish.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2081-2085
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• 2014

Second-order rate constants ($k_N$) have been measured spectrophotometrically for the reactions of phenyl 2- pyridyl carbonate (6) with a series of cyclic secondary amines in MeCN at $25.0{\pm}0.1^{\circ}C$. The Br${\o}$nsted-type plot for the reaction of 6 is linear with ${\beta}_{nuc}$ = 0.54, which is typical for reactions reported previously to proceed through a concerted mechanism. Substrate 6 is over $10^3$ times more reactive than 2-pyridyl benzoate (5), although the reactions of 6 and 5 proceed through the same mechanism. A combination of steric hindrance, inductive effect and resonance contribution is responsible for the kinetic results. The reactions of 6 and 5 proceed through a cyclic transition state (TS) in which H-bonding interactions increase the nucleofugality of the leaving group (i.e., 2-pyridiniumoxide). The enhanced nucleofugality forces the reactions of 6 and 5 to proceed through a concerted mechanism. In contrast, the corresponding reaction of 4-nitrophenyl 2-pyridyl carbonate (7) proceeds through a stepwise mechanism with quantitative liberation of 4-nitrophenoxide ion as the leaving group, indicating that replacement of the 4-nitrophenoxy group in 7 by the PhO group in 6 changes the reaction mechanism (i.e., from a stepwise mechanism to a concerted pathway) as well as the leaving group (i.e., from 4-nitrophenoxide to 2-pyridiniumoxide). The strong electron-withdrawing ability of the 4-nitrophenoxy group in 7 inhibits formation of a H-bonded cyclic TS. The presence or absence of a H-bonded cyclic TS governs the reaction mechanism (i.e., a concerted or stepwise mechanism) as well as the leaving group (i.e., 2-pyridiniumoxide or 4-nitrophenoxide).