• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.148-158
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• 2019

The corrosion protection of AA2024 PPy coated samples doping with nanosized metal oxides, including $TiO_2$ and $CeO_2$ nanoparticles and $Nd_2O_3$ nanorods, during exposure to the solutions of 0.1 M $H_2SO_4$ and 3.5% NaCl was evaluated by electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques. The nanorods of $Nd_2O_3$ were synthesized by cathodic pulse electrochemical deposition technique. The barrier properties of the different PPy coatings containing nanosized metal oxides immersed in $H_2SO_4$ solution were ranked as follows: $Nd_2O_3$ > $TiO_2$ > $CeO_2$. Therefore, the $Nd_2O_3$ coating sample provided the highest corrosion protection at any time of immersion up to 72 hours after immersing in $H_2SO_4$ solution. On the other hand, the $CeO_2$ coating sample displayed the best anticorrosive properties among the other coating samples after immersion in NaCl solution up to 28 days. This is due to the inhibition effect of cerium ions on aluminum alloys at near-neutral solutions.

• 유기물자원화
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• 제24권4호
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• pp.39-48
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• 2016

본 연구에서는 폐기물매립지 운영자, 관계 공무원 및 지역주민들에게 폐기물매립에 관한 정보 제공은 물론 실시간으로 폐기물매립지의 운영 및 관리를 최적화할 수 있는 매립 정보관리 시스템을 개발하였다. 매립 정보관리 시스템은 두 개의 시스템 (폐기물 매립이력 관리 시스템 및 매립 진척상황 관리 시스템)로 구성되어 있다. 자동화된 RFID / LPR 방식에 의한 고형 폐기물 매립이력 관리 시스템은 폐기물 수거 차량과 반입폐기물의 정보를 관리하며, 또한 폐기물매립지 외각에 설치된 추적 카메라를 이용하여 폐기물의 매립위치 및 매립시간 등의 정보를 3차원으로 DB화하여 향후 매립폐기물의 자원화 및 사후토지 이용 시 필요한 매립이력을 제공할 수 있도록 하였다. 매립진척상황 정보관리 시스템은 레이저 스캐너를 이용하여 실시간으로 매립지 부피 및 용량을 3차원으로 관리하여 매립진척상황을 실시간으로 산정할 수 있도록 하여 향후 매립지 잔여용량 분석을 통한 수요예측이 가능하도록 하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권5호
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• pp.662-669
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• 2011

An experiment was conducted with broiler (Cobb 400) male chicks (n = 480) to determine the effect of betaine (Bet) supplementation (0 and 800 mg/kg) to diets containing five concentrations (15, 18, 20, 22 and 24 g/kg crude protein, CP) of methionine (Met) in a $2{\times}5$ factorial study for performance, carcass traits, immune responses, and serum parameters. Each diet was fed ad libitum from 1 to 42 d of age to 8 replicates of 6 chicks. Birds were housed in battery brooders placed in an open-sided poultry shed. Body weight gain, feed intake, feed conversion efficiency and slaughter variables were recorded at 21 and 42 d of age. Serum biochemical profile, antibody production against Newcastle disease (ND) and lymphocyte proliferation ratio (LPR) were analysed at 42 d of age. Supplementing Bet to diets containing sub-optimal concentrations of Met (15 g/kg) improved weight gain and breast yield at 21 d of age (p<0.01), and feed conversion efficiency at 42 d of age (p<0.05). Feed efficiency at 21 d of age, body weight gain at 42 d of age, slaughter variables except breast yield at 21 d of age and ND antibody titres were not affected (p>0.05) by the interaction. LPR increased (p<0.05) with Bet supplementation at 20 g Met/kg CP equal to those broilers fed 24 g Met without Bet. Bet supplementation enhanced the concentrations of protein, globulin and cholesterol in serum of broilers fed sub-optimal concentrations of Met. Results suggested that Bet supplementation (800 mg/kg diet) enhanced growth (21 d), feed conversion efficiency (42 d), breast yield and lymphocyte proliferation in broilers fed a diet containing 15 g Met/kg CP.

• International Journal of Concrete Structures and Materials
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• 제1권1호
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• pp.83-88
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• 2007

This paper discusses a method of measuring transient potential response of a corrosion interface to a small galvanostatic pulse perturbation for a rapid assessment of the corrosion rate of reinforcing steel in concrete structures. Measurements were taken on 100 mm sections of steel bars which were subjected to a wide range of corrosion conditions, from passive steel to actively corroding steel. The duration of the applied galvanostatic pulse was varied between 5s and 180s, and the lateral distance of the point of measurement on the steel bar varied from zero to 400 mm. The result of the electrochemical transient response was investigated using a typical sampling rate of 1 kHz. Analysis of the transient potential response to the applied galvanostatic pulse has enabled the separation of equivalent electronic components so that the components of a series of capacitances and resistances, whose values are dependent on the corrosion condition of the reinforcing steel, could be isolated. The corrosion rate was calculated from a summation of the separate resistive components, which were associated with the corrosion interface, and was compared with the corrosion rate obtained from linear polarization resistance (LPR) method. The results show that the galvanostatic pulse transient technique enables the components of the polarization resistance to be evaluated separately so as to give more reliable corrosion rate values than those obtained from the LPR method. Additionally, this paper shows how the galvanostatic pulse transient response technique can be implemented. An appropriate measurement time for passive and actively corroding reinforcing steel is suggested for the galvanostatic pulse transient response measurements in the field site.

• 한국압력기기공학회 논문집
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• 제8권3호
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• pp.13-22
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• 2012

According to recent research on leak-rate estimates to assess rupture probabilities of nuclear piping which contains a circumferential surface/through-wall cracks due to PWSCC, i.e., xLPR (Extremely Low Probability of Rupture) program, it has been revealed that the use of crack shape with an idealized circumferential through-wall crack during actual crack growth can lead to overestimate of the leak-rate. Thus, for accurate estimation of the leak-rate during crack growth, the more realistic crack shape that can simulate the crack shape transition from surface crack to through-wall crack should be used. In this context, in the present study, the elastic crack opening displacement of slanted circumferential through-wall crack in thick-walled cylinder was proposed based on 3-dimensional elastic finite element fracture mechanics analyses. To propose the elastic crack opening displacement of slanted circumferential through-wall crack in thick-walled cylinder, the geometric variables affecting crack opening displacement, i.e., thickness of cylinder, reference inner crack length and slant crack ratio were systematically varied. In terms of loading conditions, axial tension, global bending moment and internal pressure were considered. The present results can be applied to calculate the leak-rate considering more realistic crack shape transition from surface crack to idealized through-wall crack, and can be expected to enhance current leak-rate estimation scheme, for instance, in xLPR program etc.

• 대한기관식도과학회지
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• 제15권1호
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• pp.41-49
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• 2009

Background and Objectives : Proton pump inhibitors(PPIs) improve the symptoms of laryngopharyngeal reflux(LPR). But there is little reports about the changes of each items in reflux symptom index (RSI) and reflux finding score (RFS) after PPIstreatment. The purpose of this study is to analyze the changes of pre- and post-treatment score in each RSI and RFS items after 8 weeks medication with proton pump inhibitors in laryngopharyngeal reflux patients. Methods : Prospective study. Among the patients who had visited the department of otolaryngology from January 2007 to December 2008, 91 patients who had shown scores greater than 13 on the RSI and/or 7 on the RFS were studied. All patients received PPIs once daily before breakfast for 8 weeks. RSI and RFS were assessed at initial, four weeks and eight weeks after medication. Result: All RSI items were improved (p < 0.05). The globus sense followed by throat clearing, heartburns and hoarseness showed high initial RSI score than other items. And globus sense, throat clearing, hoarseness and heartburn were improved significantly more than others items. But only posterior commissure hypertrophy of RFS was improved significantly more than others items. Conclusion: Empiric PPIs therapy reduced the RSI scores and more effective for symptoms such as globus sense, throat clearing, hoarseness and heartburn among suspected LPR patients. In RFS, only posterior commissure hypertrophy has improved significantly. However, the changes of each categories of RFS were minimal (average: 0.16), therefore clinical significance is restricted in RFS.

• 대한후두음성언어의학회지
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• 제32권1호
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• pp.24-28
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• 2021

Background and Objectives Vocal polyp is one of the most common benign diseases of vocal fold caused by overuse of voice. Laryngeal microsurgery is the first treatment of choice for vocal polyp. However, surgery has many risks such as side effects of general anesthesia, injury of tooth and psychological burden. And we often experience reduction of vocal polyps without surgical procedure. The purpose of study is to evaluate the effect of non-surgical treatment such as vocal hygiene education and proton pump inhibitor (PPI) in patients with vocal polyp. Materials and Method We performed retrospective study for seventy-three patients of vocal polyp who treated with non-surgical modalities such as vocal hygiene education and PPI over three months. Treatment outcomes and risk factors such as age, sex, polyp size, position, symptom duration, presence of laryngopharyngeal reflux (LPR) symptoms, smoking history, voice abuse history and vocal hygiene education were evaluated by comparison between polyp size improved group and non-improved group. Results 5.5% of enrolled patients showed complete response and 23.3% showed partial response without surgery. Polyp size improved group significantly carried out more practice of vocal hygiene education treatment than the non-improved group (p=0.040). And the presence of LPR symptoms [hazard ratio (HR) 3.368, confidence interval (CI) 1.055-10.754, p=0.040] and not performing of vocal hygiene education (HR 3.664, 95% CI 1.078-12.468, p=0.038). Conclusion Vocal hygiene education can be a useful treatment option when making a decision to treat with vocal polyp.

• 한국방사선학회논문지
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• 제15권6호
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• pp.891-897
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• 2021

핵의학은 방사성 동위원소 추적자를 인체에 투여하여 질병의 형태학적 정보와 생물학적 기능 정보를 얻고 평가한 Amyloid PET Tracer 개발로 베타아밀로이드 신경반 확인을 통해서 알츠하이머 진단의 정확도를 높일 수 있다. 그러나 20분이라는 긴 영상획득 시간은 환자에게 힘든 시간 일 수 있다. PET/CT 검사는 환자의 움직임에 민감하며, 검사 결과에도 일부분 영향을 미칠 수 있다. 이에 본 연구에서는 체내 방사성 의약품의 분포를 시간에 따른 list mode acquisition 방법을 통해 영상의 정량적 평가에 영향을 미치지 않으면서 적절한 영상획득 시간 연구하였다. list mode는 기존의 frame mode에 비해 시간에 대한 정보가 포함되어 연구자들이 원하는 시간에 대한 영상을 별도로 reconstruction 할 수 있어 data 분석에 용이하다. 연구 방법은 5 min frame/bed, 10 min frame/bed, 15 min frame/bed, 20 min frame/bed 로 리스트 모드를 이용하여 시간별 재구성 영상을 획득하여 SNR(signal to noise ratio) 과 LPR(lesion-to-pons uptake ratio)의 차이와 판독의 차이를 비교 분석하여 적정한 영상획득시간을 알아보고자 하였다. 정량적 분석 결과 list mode로 측정 시 정량적 평가 결과, 영상획득 시간이 증가함에 따라 관심 영역 6개에서 SUVmean 값은 감소하였으나 5 min/bed 영상에서 가장 많은 차이를 보였고 10 min/bed 그리고 15 min/bed 순으로 SUVmean 값의 차이가 감소하였다. 따라서 15 min/bed 에서의 SUVmean 값은 영상의 평가에 영향을 끼치지 않을 만큼의 차이가 없다는 결과값이 나왔다. LPR 값의 차이는 없었다. 정성적 분석 결과, PET 영상획득시간에 따른 판독 소견의 변화는 없었으며 시간에 따른 영상 재구성의 정성적 분석 점수의 유의한 차이가 없었다. 연구 결과 F-18 fluteme tamol PET/CT 검사 시 15 min/bed 과 20 min/bed 영상이 유의한 차이가 없으므로 환자의 상태에 따라 LIST MODE를 통해 선택적으로 15 min/bed 을 사용하여 영상획득 시간을 줄이는 것이 임상적으로 유용하다고 할 수 있다.

• ETRI Journal
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• 제37권2호
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• pp.251-261
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• 2015

We present a novel method for real-time automatic license plate detection in high-resolution videos. Although there have been extensive studies of license plate detection since the 1970s, the suggested approaches resulting from such studies have difficulties in processing high-resolution imagery in real-time. Herein, we propose a novel cascade structure, the fastest classifier available, by rejecting false positives most efficiently. Furthermore, we train the classifier using the core patterns of various types of license plates, improving both the computation load and the accuracy of license plate detection. To show its superiority, our approach is compared with other state-of-the-art approaches. In addition, we collected 20,000 images including license plates from real traffic scenes for comprehensive experiments. The results show that our proposed approach significantly reduces the computational load in comparison to the other state-of-the-art approaches, with comparable performance accuracy.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.509-512
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• 2005

The aim of this work is to design a real-time reusable image enhancement architecture for video signals, based on a spatial processing of the video sequence. The VHDL hardware description language has been used in order to make possible a top-down design methodology. By adding proposed algorithms to the LPR(License Plate Recognition) system, the system is implemented with reliability and safety on a rainy day. Spartan-2E XC2s300E is used as implementation platforms for real-time system.