• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.507-514
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• 2023

The selective catalytic reduction (SCR) of nitrogen oxides (NO_x) was investigated in a catalyst (Ag/γ-Al₂O₃) packed dielectric barrier discharge plasma reactor. The intermittent generation of plasma in the catalyst bed partially oxidized the hydrocarbon reductant for NO_x removal to several aldehydes. Compared to using the catalyst alone, higher NO_x conversion was observed with the intermittent generation of plasma due to the formation of highly reductive aldehydes. Under the same operating conditions (temperature: 250 ℃; C/N: 8), the NO_x reduction efficiencies were 47.5%, 92%, and 96% for n-heptane, propionaldehyde, and butyraldehyde, respectively, demonstrating the high NO_x reduction capability of aldehydes. To determine the optimal condition for intermittent plasma generation, the high voltage on/off cycle was adjusted from 0.5 to 3 min. The NO_x reduction performance was compared between continuous and intermittent plasma generation on the same energy density basis. The highest NO_x reduction efficiency was achieved at 2-min high voltage on/off intervals. The reason that the intermittent plasma discharge exhibited higher NO_x reduction efficiency even at the same energy density, compared to the continuous plasma generation case, is that the intermediate products, such as aldehydes generated from hydrocarbon, were more efficiently utilized for the reduction of nitrogen oxides.

• Smart Media Journal
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• v.13 no.2
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• pp.52-61
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• 2024

In the shipyard, aerial images are acquired at regular intervals using Unmanned Aerial Vehicles (UAVs) for the management of external storage yards. These images are then investigated by humans to manage the status of the storage yards. This method requires a significant amount of time and manpower especially for large areas. In this paper, we propose an automated management technology based on a semantic segmentation foundation model to address these challenges and accurately assess the status of external storage yards. In addition, as there is insufficient publicly available dataset for external storage yards, we collected a small-scale dataset for external storage yards objects and equipment. Using this dataset, we fine-tune an object detector and extract initial object candidates. They are utilized as prompts for the Segment Anything Model(SAM) to obtain precise semantic segmentation results. Furthermore, to facilitate continuous storage yards dataset collection, we propose a training data generation pipeline using SAM. Our proposed method has achieved 4.00%p higher performance compared to those of previous semantic segmentation methods on average. Specifically, our method has achieved 5.08% higher performance than that of SegFormer.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.3
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• pp.37-46
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• 2024

This study investigates the evolution of concrete damage due to chloride-induced steel corrosion through Impact-echo (IE) testing. Three reinforced concrete specimens, each measuring 1500 mm in length, 400 mm in width, and 200 mm in thickness, were fabricated using three concrete mixture proportions of blended cement types: ordinary Portland cement, ground granulated blast-furnace slag and fly ash. Steel corrosion in the concrete was accelerated by impressing a 0.5 A current following a 35-day cycle of wet-and-dry saturation in a 3% NaCl solution. Initial IE data collected during the saturation phase showed no significant changes, indicating that moisture had a minimal impact on IE signals and highlighting the slow progress of corrosion under natural conditions. Post-application of current, however, there was a noticeable decline in both IE peak frequency and the P-wave velocity in the concrete as the duration of the impressed current increased. Remarkably, progressive monitoring of IE proves highly effective in capturing the critical features of steel-corrosion induced concrete deterioration, such as the onset of internal damages and the rate of damage propagation. These results demonstrate the potential of progressive IE data monitoring to enhance the reliability of diagnosing and prognosticating the evolution of concrete damage in marine environment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.944-951
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• 2017

This study aimed to determine and examine the contents of vitamins $B_1$, $B_2$, and $B_3$ using the high-performance liquid chromatography method in traditional holiday foods in Korea. All analyses were under the quality control chart of vitamins $B_1$, $B_2$, and $B_3$. The z-scores for vitamins $B_1$, $B_2$, and $B_3$ were 1.3, 0.0, and 0.6, respectively, in food analysis performance assessment scheme proficiency tests assuring reliability of analytical performance. Vitamin $B_1$, $B_2$, and $B_3$ contents were analyzed in a total of 31 samples. Vitamin $B_1$, $B_2$, and $B_3$ contents ranged from 0.000 to 0.973 mg/100 g, from 0.037 to 0.264 mg/100 g, and from 0.000 to 1.223 mg/100 g in Korean traditional holiday foods, respectively. The highest contents of vitamins $B_1$, $B_2$, and $B_3$ were 0.973 mg/100 g in Yukwon-jeon, 0.264 mg/100 g in Dongtae-jeon, and 1.223 mg/100 g in Yukwon-jeon sample, respectively. However, compared to vitamins $B_2$ and $B_3$, vitamin $B_1$ was not detected, generally. Therefore, these results can be used as basic data for a food composition table and improvement of national health for Koreans.

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.52-60
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• 2001

Purpose: In young male patients who suffered several kinds of trauma with subsequent suspicious reflex sympathetic dystrophy syndrome, we performed three-phasic bone scan in order to investigate its usefulness. Materials and Methods: Patients with narrow range of age (21-25. mean $22.8{\pm}1.3$, all male) were included with suspicious reflex sympathetic dystrophy syndrome of 12 feet and 5 hands. Only one was bilateral feet case and 16 were ipsilateral (Rt:13, Lt:3). The etiologic traumas were 4 fractures, 4 sprains, 3 blunt trauma, 2 cellulitis, 1 tendon tear, 1 crush injury, 1 overexercise, and 1 unknown. Radiologically 3 showed osteoporotic changes. Three-phasic bone scans were performed $21.2{\pm}7.3wks$ after trauma. Results: According to symptom complex, confirmatory reflex sympathetic dystrophy syndrome 4 cases and suspicious 13 were analyzed. All confirmatory cases (100%) showed increased uptake at delay phase with periarticular accentuation. Of confirmatory 4 cases, 2 showed increased uptake in all three phases (perfusion: P, blood pool: B, and delay: D), and other 2 revealed decreased P but, both increased B and D. Of suspicious 13 cases, 9(69.2%) had increased D (4 periarticular and 5 focal), 2 decreased D, and 2 symmetric D. In 12 foot cases, so-called weight hearing patterns - increased contralateral sole at P and B - were revealed in 7(58.3%). Conclusion: Diffuse periarticular increased uptake at delay phase of three-phasic bone scan was a compatible finding to reflex sympathetic dystrophy syndrome in young male patients whose symptom complex strongly designated post traumatic reflex sympathetic dystrophy syndrome.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1363-1373
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• 2009

본 연구는 두 집단지성의 가장 대표적인 서비스인 네이버 지식iN과 위키피디아의 구조적, 경험적 차이를 바탕으로 생산의 차원에서 생산 주기, 생산 참여자, 생산물의 모델을 설정하고, 새롭게 탄생하는 지식을 중심으로 검증함으로써 최종 지식 소비 행위를 반영한 각각의 종합모델을 도출하였다. 우리는 웹에서 집단지성의 일상화를 확인할 수 있다. 지식 획득 매체가 매스미디어에서 인터넷으로 변화하는 과정에서 등장한 포털 및 검색사이트는 지식의 생산이 전문가패러다임에서 소비자 중심으로 재편될 수 있는 가능성을 열어주었다. 그리고 이러한 생산 방식의 변화는 '지식'의 개념 역시 변화시키고 있다. 즉, 집단지성이라는 새로운 웹2.0의 현상이 지식생산방식을 변화시키고 변화된 지식생산방식은 '지식'자체를 변화시킨다는 이론적 가설을 도출할 수 있는 것이다. 본 연구는 이러한 새로운 현상들을 분석하기 위해서는 먼저 보다 엄밀하게 집단지성의 개념을 규정할 필요성에 출발하였다. 현재 집단지성이라는 이름으로 불리면서 급격히 성장하고 있는 위키 방식의 인터넷 서비스와 지식검색 방식의 인터넷 서비스를 비교함으로써 보다 정교한 집단지성의 모델을 구축하고자 하였다. 위키형 집단지성과 지식검색형 집단지성의 차이점은 경험적으로도 뚜렷하게 확인할 수 있다. 본 연구는 이러한 경험적 차이와 기존의 문헌에서 밝혀진 사실들을 바탕으로 두 서비스의 지식생산 방식을 생산플로우, 생산참여자 성향, 생산물(지식)의 성향과 같이 세 영역으로 나누어 각각의 가설 모델을 설정하고 이 모델을 선정된 질의어를 바탕으로 검증한 뒤에 최종적인 모델을 도출하는 방식으로 진행되었다. 지식검색형 집단지성은 '질문-답변-채택'의 구조이고, 그 구조 속에서 '질문기-답변기-순서화기'를 거쳐 하나의 지식 덩어리인 'K-let'을 생산한다. 생산된 'K-let'들은 지식검색서비스의 데이터베이스에 축적되고, 이는 공통된 질의어를 기준으로 소비자들에 의해서 검색되어 소비된다. 하나의 질문에 대해 여러 개의 답변들이 존재하고, 답변자의 성향은 크게 전문성과 체계성을 바탕으로 한 전문가형 답변자와 경험적이고 의견지향적인 대화형 답변자로 나눠진다. 다수의 네티즌들의 참여에 의해서 지식의 생산이 진행되므로 질문의 성향 역시 사실, 의견, 경험 등 다양한 스펙트럼을 가지는 모델로 설정하였다. 반면에 위키형 집단지성은 개방형 플랫폼을 바탕으로 한 백과사전의 형식이며, 이러한 형식 속에서 최초의 개념어 등록과 다수의 편집활동을 거치면서 완성되지 않는 하나의 아티클인 'W-let'을 생산한다. 이러한 'W-let'은 생성 초기에 소수에 의한 활발한 내용 입력 활동으로 어느 정도의 안정화를 거친 후에는 꾸준한 다수의 수정활동을 통해서 'W-let'의 생명력을 유지함으로써 지식의 실제적인 변화를 반영한다. 생산된 'W-let'들은 위키형 집단지성 서비스의 데이터베이스에 축적되고, 이것들은 내부링크를 통해서 모두 연결되어 있다. 백과사전 형식으로 하나의 개념어를 설명하는 하나의 아티클은 오로지 사실적인 지식들로만 구성되나 내부링크와 외부링크를 통해서 다양한 스펙트럼을 가지는 모델로 설정하였다. 위와 같이 설정된 모델을 바탕으로 공통된 질의어 및 개념어를 선정하여 각각의 서비스에 노출시켰다. 이를 통해서 얻어진 각 서비스의 데이터베이스에 축적된 모든 데이터들 중에서 일정한 기간을 기준으로 각각의 모델 검증에 필요한 데이터를 추출하여 분석하는 방식으로 진행되었다. 그 결과 지식검색형 집단지성에서는 '질문-답변-채택'의 생산 구조 속에 다수가 참여하여 질문-채택답변-기타답변으로 배열되어 있는 완성된 형태의 K-let들을 지속적으로 생산하며 비슷한 성향을 가진 K-let들이 반복적으로 생산되어 지식검색 데이터베이스에 누적된다. 지식 소비자들은 질의어 검색을 통해서 다양한 K-let들을 선택하여 비교, 검토한 후에 선택된 K-let들의 배열은 해체되어 소비자들에 의해서 재배열됨을 발견할 수 있었다. 이에 지식검색형 집단지성이란 다수의 의해서 생산되고 누적된 지식들이 소비자의 검색과 선택에 의해 해체되어 재배열되는 지식의 맞춤화 과정이라고 정의내릴 수 있었다. 반면에 위키형 집단지성에서는 '내용입력-미세수정' 구조 속에서 생명력 있는 W-let을 생성한다. W-let은 백과사전처럼 정리되어 내부링크를 통해서 서로 연결되고, 외부링크를 통해 확장되고, 지식소비자들은 검색을 통해 최초의 W-let에 도달한 후에 링크를 선택함으로써 지식을 확장시킴을 검증할 수 있었다. 따라서 위키형 집단지성이란 다수의 의해서 생산되고 정리된 지식들이 소비자의 검색과 링크에 의해 무한히 확장되는 지식의 확대 재생산되는 과정이라고 정의 내릴 수 있다. 결국, 현재의 집단지성이란 지식이 다수의 참여로 생산됨으로써 개인에게 맞춤화되고, 끊임없이 확대 재생산되는 과정을 의미한다. 그리고 이러한 집단지성의 방식은 지식이라는 현재의 차원을 넘어서 정치, 경제를 비롯한 사회의 전 영역으로 점차적으로 확대되어갈 것이다. 앞으로 연구들은 두 가지 모델이 혼재되어 있는 현재의 집단지성이 어떠한 새로운 모델을 만들면서 다른 영역으로 확장되어갈 것인지에 대해서 초점을 맞춰 나가야할 것이다.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.747-753
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• 2008

Purpose : Diabetes mellitus is a major risk factor for the development of cardiovascular disease. Early atherosclerotic changes in the arterial walls begin in adolescence and the risk factors are associated with its development. To assess the usefulness of carotid artery intima-media thickness (IMT), as a marker of early atherosclerosis, we evaluated the structural and functional characteristics of the carotid artery and investigated their relationshop with the metabolic and anthropometric parameters in children and adolescents with type 1 diabetes. Methods : For this study, we enrolled 23 children with type 1 diabet and 19 age and sex-equivalent healthy children as the control group. Metabolic and anthropometric parameters such as serum lipid levels, plasma glycated hemoglobin (HbA1c), and body mass index were measured after a 12-h fasting period. The carotid artery IMT was measured by a high-quality ultrasound system, and compliance, and distensibility were calculated by an equation. Results : There were no significant differences between the 2 groups with regard to the sex ratio, age, blood pressure and serum cholesterol levels' however, HbA1c levels were significantly higher in the diabetic children ($8.5{\pm}1.8$ vs. $5.0{\pm}0.2$, P=0.001). Ultrasonographic findings showed that compared with the control group, the diabetic group had higher IMT ($0.45{\pm}0.06mm$ vs. $0.41{\pm}0.04mm$, P=0.04), but there were no significant differences in compliance and distensibility. The HbA1c (P=0.002) and high-density lipoprotein cholesterol (P=0.026) levels were independent IMT predictors in the diabetic group. Conclusion : Here, the carotid artery IMT was higher in the diabetic group, and it is correlated with atherosclerotic risk factor. Thus, carotid IMT could be evaluated as a marker of early atherosclerosis in diabetic children.

• Journal of Astronomy and Space Sciences
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• v.26 no.3
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• pp.305-316
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• 2009

In this study, we suggest an empirical forecast of CIR (Corotating Interaction Regions) and geomagnetic storm based on the information of coronal holes (CH). For this we used CH data obtained from He I $10830{\AA}$ maps at National Solar Observatory-Kitt Peak from January 1996 to November 2003 and the CIR and storm data that Choi et al. (2009) identified. Considering the relationship among coronal holes, CIRs, and geomagnetic storms (Choi et al. 2009), we propose the criteria for geoeffective coronal holes; the center of CH is located between $N40^{\circ}$ and $S40^{\circ}$ and between $E40^{\circ}$ and $W20^{\circ}$, and its area in percentage of solar hemispheric area is larger than the following areas: (1) case 1: 0.36%, (2) case 2: 0.66%, (3) case 3: 0.36% for 1996-2000, and 0.66% for 2001-2003. Then we present contingency tables between prediction and observation for three cases and their dependence on solar cycle phase. From the contingency tables, we determined several statistical parameters for forecast evaluation such as PODy (the probability of detection yes), FAR (the false alarm ratio), Bias (the ratio of "yes" predictions to "yes" observations) and CSI (critical success index). Considering the importance of PODy and CSI, we found that the best criterion is case 3; CH-CIR: PODy=0.77, FAR=0.66, Bias=2.28, CSI=0.30. CH-storm: PODy=0.81, FAR=0.84, Bias=5.00, CSI=0.16. It is also found that the parameters after the solar maximum are much better than those before the solar maximum. Our results show that the forecasting of CIR based on coronal hole information is meaningful but the forecast of goemagnetic storm is challenging.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.98-106
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• 2003

Background : To evaluate the efficacy and safety of gemcitabine and cisplatin chemotherapy in advanced non-small cell lung cancer (NSCLC). Materials and Methods : Forty patients (21 men, 19 women ; age range, 37 to 73 years; median, 63 years) with unresectable stage IIIB to IV NSCLC were evaluated. Patients received cisplatin $60mg/m^2$ (Day 1), gemcitabine $1200mg/m^2$ (Day 1 and 8) every 21 days. Eighteen patients had stage IIIB disease and 22 had stage IV. There were 28 patients of adenocarcinoma (70.0%), 11 of squamous cell carcinoma (27.5%), and one of large cell carcinoma (2.5%). Results : Of 40 patients, no patients showed complete response while 15(37.5%) showed partial response, 7(17.5%) had stable diseases, 18(45%) had progressive diseases. During a total of 195 courses of chemotherapy, grade 3 or more granulocytopenia and thrombocytopenia occured in 12.5% and 2.5% of patients respectively. Non-hematologic toxicity was mild and easily controlled. There was one case of treatment-related death by pneumomia. The median survival was 55 weeks (95% CI, 34~75weeks), and the time to progression was 19 weeks (95% CI, 16~23weeks). One year survival rate was 55% and 2 year survival rate was 10%. Conclusion : The efficacy of cisplatin and gemcitabine combination chemotherapy was acceptable in the treatment of advanced NSCLC.

• Pediatric Infection and Vaccine
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• v.6 no.1
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• pp.86-92
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• 1999

Purpose : The purpose of this study is to know the epidemiology and clinical characteristics in patients with M. pneumoniae pneumonia during study period retrospectively. Methods : We had reviewed 500 patients with Mycoplasma pneumoniae pneumonia who were hospitalized at the pediatric ward of Seoul Adventist Hospital from July 1986 through June 1996. we had analysed clinical and laboratory problems of pulmonary and extrapulmonary manifestations including demographics and epidemiological characteristics. Results : Peak occurrence of the disease was 3 years interval and seasonal occurrence of the disease had no difference. 43.4% of patients was below 4 years old and male to female ratio was nearly 1:1. The most common site of infiltration on chest PA was right lower lobe and the most common type of pneumonia was interstitial pneumonia(43%). Pulmonary complications were atelectasis(11cases), emphysema(5cases), pleural effusion(27cases) and sinusitis(13cases) and extrapulmonary manifestations were hepatitis(109cases), skin rash(29cases), proteinuria(20cases) and hematuria(16cases). cold agglutinin test was carried out in 500cases and mycoplasma antibody test was carried out in 448cases. sensitivity of mycoplasma antibody test was 53.3%. Conclusion : Mycoplasma pneumoniae pneumonia showed epidemics at intervals of 3 year in its major occurrence. it exhibits a tendency that occurs at younger age group not in school age group. diagnosis of the disease need more accurate method due to low sensitivity of mycoplasma antibody test. also we need to carried out other laboratory test(for example, LFT, U/A).