• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권7호
• /
• pp.364-366
• /
• 2006

In order to realize the commercial application of HTSC materials, it is necessary to develop the fabrication process of high Tc oxide superconductor materials with desired shape and for practical application and high critical current density as well as good mechanical strength which can withstand high lorenz force generated at high magnetic field. Much studies have been concentrated to develop the fabrication technique for high critical current density but still there are a lot of gap which should be overcome for large scale application of HTSC materials at liquid nitrogen temperature. Recently some new fabrication techniques have been developed for YBaCuO bulk superconductor with high mechanical strength and critical current density. In this project, the establishment of fabrication condition and additive effects of second elements were examined so as to improve the related properties to the practical use of YBaCuO superconductor, and we reported the production of the YBaCuO high Tc superconductor by the pyrolysis method.

• Clinical and Experimental Pediatrics
• /
• 제64권9호
• /
• pp.436-442
• /
• 2021

This article aimed to summarize the impact and burden of pediatric postintensive care syndrome (PICS-p) in the physical, mental, cognitive, and social health domains after a review of the current pediatric literature in MEDLINE and PubMed. We also aimed to elucidate the limitations of the current evaluation tools used in limited-resource settings. PICS-p can impact a child's life for decades. Most validated tools are time-consuming, require qualifications, and expertise, are often limited to older children, and can evaluate only one domain. A novel, simple, and comprehensive surveillance tool can aid healthcare providers in the early detection and intervention of PICS-p. Further studies should validate and refine the parameters that will enhance the outcomes of pediatric intensive care unit survivors.

• Current Optics and Photonics
• /
• 제6권6호
• /
• pp.583-589
• /
• 2022

Vanadium dioxide (VO₂) is a well-known material that undergoes insulator-to-metal phase transition near room temperature. Since the conductivity of VO₂ changes several orders of magnitude in the terahertz (THz) spectral range during the phase transition, VO₂-based active metamaterials have been extensively studied. Experimentally, it is reported that the metal nanostructures on the VO₂ thin film lowers the critical temperature significantly compared to the bare film. Here, we theoretically studied such early transition phenomena by developing an analytical model. Unlike experimental work that only measures transmission, we calculate the reflection and absorption and demonstrate that the role of absorption is quite different for bare and patterned samples; the absorption gradually increases for bare film during the phase transition, while an absorption peak is observed at the critical temperature for the metamaterials. In addition, we also discuss the gap width and VO₂ thickness effects on the transition temperatures.

• Tuberculosis and Respiratory Diseases
• /
• 제53권2호
• /
• pp.234-237
• /
• 2002

대량의 백반을 자살 목적으로 음독한 증례로서 산혈증, 급성 폐손상, 다장기 부전, 불응성 쇽으로 급속히 진행하여 사망한 경우이다.

• Nutrition Research and Practice
• /
• 제4권2호
• /
• pp.163-172
• /
• 2010

The purposes of this study were to assess hospital foodservice quality and to identify causes of quality problems and improvement strategies. Based on the review of literature, hospital foodservice quality was defined and the Hospital Foodservice Quality model was presented. The study was conducted in two steps. In Step 1, nutritional standards specified on diet manuals and nutrients of planned menus, served meals, and consumed meals for regular, diabetic, and low-sodium diets were assessed in three general hospitals. Quality problems were found in all three hospitals since patients consumed less than their nutritional requirements. Considering the effects of four gaps in the Hospital Foodservice Quality model, Gaps 3 and 4 were selected as critical control points (CCPs) for hospital foodservice quality management. In Step 2, the causes of the gaps and improvement strategies at CCPs were labeled as "quality hazards" and "corrective actions", respectively and were identified using a case study. At Gap 3, inaccurate forecasting and a lack of control during production were identified as quality hazards and corrective actions proposed were establishing an accurate forecasting system, improving standardized recipes, emphasizing the use of standardized recipes, and conducting employee training. At Gap 4, quality hazards were menus of low preferences, inconsistency of menu quality, a lack of menu variety, improper food temperatures, and patients' lack of understanding of their nutritional requirements. To reduce Gap 4, the dietary departments should conduct patient surveys on menu preferences on a regular basis, develop new menus, especially for therapeutic diets, maintain food temperatures during distribution, provide more choices, conduct meal rounds, and provide nutrition education and counseling. The Hospital Foodservice Quality Model was a useful tool for identifying causes of the foodservice quality problems and improvement strategies from a holistic point of view.

• 대한토목학회논문집
• /
• 제35권5호
• /
• pp.1111-1121
• /
• 2015

회전교차로는 각 접근로의 진입교통량이 불균형할 경우 주 접근로의 대기행렬이 길어지게 됨으로 회전교차로 전체의 용량이 감소되는 단점이 있다. 이에 보통 1대의 신호등으로 운영되는 Metering 회전교차로의 연구가 활발히 진행되고 있지만 2대의 신호등에 의해 운영되는 Metering 회전교차로의 연구는 미흡하다. 교차로 분석에 널리 사용되는 SIDRA6 또한 2대의 신호등으로 구성된 회전교차로의 분석에 제약이 있다. 따라서 본 연구에서는 실제 2대의 신호등으로 운영되는 호주 Adelaide의 Old Belair 회전교차로를 대상으로 4-nodes Intersection을 이용한 새로운 분석방법을 제시하고 분석을 실시하였다. 모형 구축 방법에서 4개의 독립 교차로 연결, 기하구조 반영, 방향별 교통량 입력, 우선권 및 신호현시에 대해 설명하였으며 정산방법에서는 PFF, Critical Gap, Follow-up Headway 그리고 Extra Bunching 값의 적용에 대하여 제시 하였다. 그 결과 회전교차로의 효과척도인 지체시간 및 서비스 수준의 분석이 가능하며 그 외 포화도 및 상충교통량 등 다양한 분석이 가능한 것으로 나타났다.

• Nuclear Engineering and Technology
• /
• 제26권2호
• /
• pp.212-224
• /
• 1994

원형도관내의 비점성유동장에 놓인 동심인 유연성 실린더의 안정성을 분석하기 위하여 수치해석적방법이 개발되었다. 진동하는 실린더에 작용하는 비정상·비점성 유체유발력을 스펙트럼 배치방법을 사용하여 지배방정식을 단순화시키지 않음으로서 더 정밀하게 예측하였다. 본 수치해석이론은 기존의 퍼텐샬이론과 비해 비교적 넓은 환의 경우와 짧은 실린더의 경우에도 적용할 수 있다. 비점성유동의 지배방정식은 라플라스방정식으로부터 구하였다. 유체유동과 결부된 실린더의 유동방정식은 갤러킨의 방법에 의하여 불연속방정식으로 표시되며 이로부터 계의 운동특성을 검토하였다. 계가 좌굴현상에 의하여 안정성을 잃는 임계유속에 대한 환의 간격과 실린더의 길이의 영향이 검토되었다. 수치해석방법을 입증하기 위하여 얇은 막 근사이론에 근거를 두고 호프슨이 제안한 퍼텐샬이론을 개선하였다. 계의 안정성과 동적특성을 수치해석방법에 의하여 예시하였고 기존의 이론과 본 연구에서 제안된 근사법으로 구한 결과와 비교하여 잘 일치함을 보였다. 무차원화된 임계유속은 환의 간격이 넓을수록 실린더의 길이 가 짧을수록 증가함을 보였다.

• 한국환경농학회지
• /
• 제41권3호
• /
• pp.153-157
• /
• 2022

BACKGROUND: The residue dissipation pattern of pesticides for agricultural products during the pre-harvest period after the final application is important to prevent the maximum residue limit (MRL) violations in domestic and export markets. The MRL violations of carbendazim are observed more often in chamnamul by pesticide residue management surveys by the Ministry of Food and Drug Safety. The residue level at the pre-harvest interval (PHI) and the residue dissipation constant from the critical good agricultural practice (cGAP) trials could be estimated to meet the MRL and pose a health risk to consumers. METHODS AND RESULTS: Chamnamuls were harvested at 0, 1, 3, 5, 7, 10, and 14 days after application of carbendazim in accordance with critical GAP. The residue analysis in chamnanul was performed by HPLC-DAD with the C₁₈ column. The limit of quantitation of carbendazim was 0.04 mg/kg, and the recoveries were 74.4 - 95.8% at the two spiked levels (LOQ and 10LOQ) of carbendazim. The dissipation rates in chamnamul were calculated from the residues at the sampling days by statistical method at a 95% confidence level. The biological half-lives of residual carbendazim in the field trials 1 and 2 were 4.9 and 4.4 days, respectively. CONCLUSION(S): In this dissipation study, the residue concentrations at the recommended PHI were higher than the established MRL in Korea. Therefore, the MRL is proposed based on the residue data sets from the trials conducted at the same cGAP and the dietary exposure assessment.

• Human Ecology Research
• /
• 제54권5호
• /
• pp.487-498
• /
• 2016

The study was examined the multiple mediated effects of maternal self-efficacy and depression between perception gap about paternal involvement and marital conflict for dual-income parents. The data used were the fifth year data of the Panel Study on Korean Children from Korea Institute of Child Care and Education in 2012. The subjects consisted of 449 dual-income parents with more than one child. Data were analyzed using descriptive statistics, one-way analysis of variance, paired t -test, and correlation. SPSS macro and bootstrapping methods also assessed the mediation effects of maternal self-efficacy and depression between the perception gap about paternal involvement and marital conflict in dual-income parents. The results of this study were as follows. Significant positive correlations were observed for marital conflict, perception gap of dual-income parents about paternal involvement and maternal depression. Perception gaps by parents and self-efficacy were negatively correlated. Perception gaps by parents showed a direct effect on marital conflict. The results of indirect effects of all mediators showed the mediated effect of maternal self-efficacy and depression. The study revealed that the perceptive gap about paternal involvement has a significant impact on maternal self-efficacy and depression, as well as marital conflict. The perceptive gap of dual-income parents about paternal involvement has critical effects on marital conflict as much as the quantity of paternal involvement.

• 전기의세계
• /
• 제22권5호
• /
• pp.19-32
• /
• 1973

This paper treats with some of plasma jet behaviors under magnetic field for the purpose of controlling important characteristics of plasma jet in the practices of material manufacturings. Under the existence and non-existence of magnetic field, the pressure distribution, flame length, stability and noise of plasma jet are comparatively evaluated in respect of such parameters as are current, gap of electrode, quantity of argon flow, magnetic flux density, diameter and length of nozzle. The results are as follows: 1) the pressure, the length and the noise of plasma jet rise gradually with the increase of are current, and have high values under identical arc current as the diameter of nozzle increases, but reverse phenomenon tends to appear in the noise. 2) The pressure, the flame length and the noise increase with the increased quantity of argon flow, and the rising slope of noise is particularly steep. Under magnetic field, the quantity of argon flow in respect of flame length has the critical value of 80(cfh). 3) The pressure and length of flame decrease with small gradient value as the length of gap increases, but the noise tends to grow according to the increase of nozzle diameter. 4) The pressure and the length of jet flame decrease inversly with the increase of magnetic flux density, which have one critical value in the 100 amps of arc current and two values in 50 amps. The pressure of jet flame can be below atomospher pressure in strong magnetic field. 5) "The constriction length of nozzle has respectively the critical value of 6(mm) for pressure and 23(mm) for the length of flame. 6) Fluctuations in the wave form of voltage become greater with the increase of argon flow and magnetic flux density, but tends to decrease as arc current increases, having the frequency range of 3-8KHz. The wave form of noise changes almost in parallel with that of voltage and its changing value increases with argon flow, arc current and magnetic flux density, having the freuqency range of 6-8KHz. The fluctuation of jet presurre is reduced with the increase of argon flow and magnetic flux density and grows with arc current.rent.