• Title/Summary/Keyword: critical gap

Search Result 449, Processing Time 0.027 seconds

Fabrication Technology of high Tc Superconductor for Electrical Equipment (전력기기 초전도 합성기술)

  • Lee, Sang-Heon
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.55 no.7
    • /
    • 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.

Pediatric postintensive care syndrome: high burden and a gap in evaluation tools for limited-resource settings

  • Chaiyakulsil, Chanapai;Opasatian, Rapee;Tippayawong, Paweethida
    • Clinical and Experimental Pediatrics
    • /
    • v.64 no.9
    • /
    • 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.

A Theoretical Study on the Low Transition Temperature of VO2 Metamaterials in the THz Regime

  • Kyoung, Jisoo
    • Current Optics and Photonics
    • /
    • v.6 no.6
    • /
    • 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.

A Case of 'ALUM' Intoxication Leading to ARDS (급성 호흡 곤란 증후군을 유발한 백반 중독 중독 1예)

  • Kim, Won-Jang;Park, Youn-Hee;Kim, Eun-Kyung;Lim, Chae-Man;Koh, Youn-Suck
    • Tuberculosis and Respiratory Diseases
    • /
    • v.53 no.2
    • /
    • pp.234-237
    • /
    • 2002
  • A 77-year-old female was admitted 3 hours after intentionally ingesting 5g of aluminum ammonium sulfate ('Alum') powder dissolved in water. Gastric lavage with normal saline, activated charcoal chelation, and supportive therapies were performed. She showed a high anion gap metabolic acidosis, which rapidly progressed to multiple organ failure including ARDS. The patient subsequently progressed to a refractory shock which eventually led to death.

Assessment of foodservice quality and identification of improvement strategies using hospital foodservice quality model

  • Kim, Kyung-Joo;Kim, Min-Young;Lee, Kyung-Eun
    • Nutrition Research and Practice
    • /
    • v.4 no.2
    • /
    • 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.

A Proposal of Two Signals Roundabout Analysis Method Using SIDRA6 (SIDRA6를 이용한 Two Signals Roundabout 분석방법 제안)

  • An, Hong Ki;Yue, Weng Long;Kim, Dong Sun
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.35 no.5
    • /
    • pp.1111-1121
    • /
    • 2015
  • Roundabouts face a congestion problem when there are unbalanced traffic conditions, especially during peak times. The congestion at roundabouts results in long delay times and low level of service. Some research has addressed congestion problems of the metering roundabout, however, few studies have focused on the congestion issues of the double signals metering roundabout. This research bridges this gap through analyzing the congestion issues of the Old Belair double signals roundabout in Adelaide. The research proposes a new analysis method based on a four-nodes intersection in order for double signals roundabout analysis to be carried out as follows: firstly, at the modeling stage, a connection of four individual intersections, adjustment of lane geometry, input of directional traffic volumes, priority and phase time set up are proposed. Secondly, for calibration, PFF, critical gap, follow-up headway and extra bunching values have been applied. The results from the analysis show that the new method is able to analyze the delay time, level of service, degree of saturation and allow for further analysis.

Dynamic Stability of a Flexible Cylinder Subjected to Inviscid Flow in a Coaxial Cylindrical Duct Based on Spectral Method (스펙트럼 배치방법에 의한 원형도관내의 비점성유동장에 놓인 유연성 실린더의 안정성 분석)

  • Sim, Woo-Gun;Bae, Yoon-Yeong
    • Nuclear Engineering and Technology
    • /
    • v.26 no.2
    • /
    • pp.212-224
    • /
    • 1994
  • A numerical method has been developed for studying the dynamics of a flexible cylinder in a coaxial cylindrical duct, immersed in inviscid flow. The unsteady inviscid fluid-dynamic force acting on the oscillating cylinder has been estimated more rigorously by means of a spectral collocation method without simplification of governing equations. This numerical approach is applicable to the system haying wider annular gap and/or shorter length of cylinder as compared to existing potential theory. The governing equation of the unsteady flow was obtained from Laplace equation. The equation of cylinder motion coupled with the fluid motion was discretized by Galerkin's method, from which the dynamic behaviour of the system has been evaluated. The effect of the length of the cylinder and the annular gap on the critical flour velocity, where the system loses stability by buckling, was investigated. To validate the numerical method, the potential flow theory developed by Hobson based on thin film approximation has been improved. Typical results of the present numerical theory on the dynamics and stability of the system are compared with those of available existing theory and the present approximate results. Good agreement was found between the results. It was also found that a nondimensional critical flow velocity becomes larger as increasing the annular gap and decreasing the length of cylinder.

  • PDF

Residues and Exposure Assessment of Carbendazim in Chamnamul on Field Trials for Revising Maximum Residue Limit in Korea (생산단계 참나물의 Carbendazim 잔류특성에 따른 노출평가 및 농약 잔류허용기준 개선)

  • Chang, Hee-Ra;Gwak, Hye-Min
    • Korean Journal of Environmental Agriculture
    • /
    • v.41 no.3
    • /
    • 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.

The Influence of Perception Gap of Dual-Income Parents about Paternal Involvement on Marital Conflict: Mediating Effects of Maternal Self-Efficacy and Depression (맞벌이 부모 간 아버지 양육참여의 지각차이가 부부갈등에 미치는 영향: 어머니의 자기효능감과 우울의 매개효과)

  • Kim, Eunji;Jeon, Gweeyeon
    • Human Ecology Research
    • /
    • v.54 no.5
    • /
    • 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.

A Study on the Influence Coaxial Parallel Magnetic Field upon Plasma Jet (II) (Plasma Jet의 동축평행자계에 의한 영향에 관한 연구 2)

  • Choon Saing Jhoun
    • 전기의세계
    • /
    • v.22 no.5
    • /
    • 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.

  • PDF