• 제목/요약/키워드: Tertiary

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MTBE(Methyl Tertiary Butyl Ether)의 토양내 이동특성에 관한 연구 (A Study on Transport Characteristics of MTBE(Methyl Tertiary Butyl Ether) in Soil)

  • 조기철;박창웅;최원준;강승엽;황종현;김윤수;오광중
    • 대한환경공학회지
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    • 제30권2호
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    • pp.190-198
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    • 2008
  • 본 연구에서는 주유소 등의 지하 유류저장탱크나 파이프의 제한된 수명으로 인해 발생할 수 있는 가솔린의 누출에 의해 MTBE로 토양이 오염되었을 경우를 가정하여, 칼럼실험을 수행하고, CXTFIT 기법을 이용하여 토양 내 MTBE의 이동특성을 살펴 보았다. 칼럼실험에서는 토성, 수분함량, 유기물함량, 주입유속을 달리하여, 주입액과 유출액의 MTBE의 농도 측정값을 비교하고, CXTFIT기법을 이용하여 two-site 비평형 흡착모델에 사용된 매개변수(D, R, $\beta$, $\omega$)를 구하였다. 이들 매개변수와 파과곡선을 이용하여 MTBE의 토양 내 이동특성을 살펴보았다. 토양 내 미세입자와 유기물함량이 많을수록 이류에 의한 영향이 감소하는 것으로 나타났으며, 수분함량과 유속의 증가는 이류에 의한 MTBE의 이동을 더욱 가속시키는 것으로 나타났다.

동축 공기다단 LPG화염의 NOx 생성특성에 관한 연구 (Characteristics of NOB Formation in a Coaxial Multi-Air Staged LPG Flame)

  • 김한석;안국영;김호근;유명종;백승욱
    • 대한기계학회논문집B
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    • 제27권2호
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    • pp.215-226
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    • 2003
  • Experimental and numerical studies have been done to examine the effects of excess air ratio and tertiary air swirl number on the formation characteristics of NOx in a pilot scale combustor adopting a multi-air staged burner. In numerical calculation the mathematical models for turbulence, radiation and nitric oxide chemistry were taken into account. The radiative transfer equation was solved using the discrete ordinates method with the weighted sum of gray gases model. In the NOx chemistry model, the chemical reaction rates for thermal and prompt NOx were statistically averaged using a probability density function. The results were validated by comparison with measurements. For the experiment, a 0.2 MW pilot multi-staged air burner has been designed and fabricated. Using the numerical simulation developed here, a variation of thermal and prompt NOx formation was predicted by changing the excess air ratio and tertiary air swirl number. As the excess air ratio increased up to 1.9, the formation of the total as well as thermal NOx at exit increased while the prompt NOx decreased. The formation of thermal NOx was more affected by concentration of $O_2$ and $N_2$ than gas temperature. When the tertiary air swirl number increased, the formation of the total as well as the prompt NOx slightly decreased.

Orienting the superficial inferior epigastric artery (SIEA) pedicle in a stacked SIEA-deep inferior epigastric perforator free flap configuration for unilateral tertiary breast reconstruction

  • Yu, Ya-han;Ghorra, Dina;Bojanic, Christine;Aria, Oti N.;MacLennan, Louise;Malata, Charles M.
    • Archives of Plastic Surgery
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    • 제47권5호
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    • pp.473-477
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    • 2020
  • Superficial inferior epigastric artery (SIEA) flaps represent a useful option in autologous breast reconstruction. However, the short-fixed pedicle can limit flap inset options. We present a challenging flap inset successfully addressed by de-epithelialization, turnover, and counterintuitive rotation. A 47-year-old woman underwent left tertiary breast reconstruction with stacked free flaps using right deep inferior epigastric perforator and left SIEA vessels. Antegrade and retrograde anastomoses to the internal mammary (IM) vessels were preferred; additionally, the thoracodorsal vessels were unavailable due to previous latissimus dorsi breast reconstruction. Optimal shaping required repositioning of the lateral ends of the flaps superiorly, which would position the ipsilateral SIEA hemi-flap pedicle lateral to and out of reach of the IM vessels. This problem was overcome by turning the SIEA flap on its long axis, allowing the pedicle to sit medially with the lateral end of the flap positioned superiorly. The de-epithelialized SIEA flap dermis was in direct contact with the chest wall, enabling its fixation. This method of flap inset provides a valuable solution for medializing the SIEA pedicle while maintaining an aesthetically satisfactory orientation. This technique could be used in ipsilateral SIEA flap breast reconstructions that do not require a skin paddle, as with stacked flaps or following nipple-sparing mastectomy.

피압지하수에 의한 자연사면 연약층내의 간극수압 반응에 관한 모형 실험 연구 (A Laboratory Model Study on the Reactions of the Pore Water Pressure in the Weakened Layer of a Natural Slope by the Confined Groundwater)

  • 정두영;이광준
    • 대한토목학회논문집
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    • 제14권3호
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    • pp.583-594
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    • 1994
  • 자연사면 붕괴의 주요인의 하나는 연약층에서의 간극수압 상승이다. 따라서 이 연약층내의 간극수압 계측이 중요하다. 본 연구는 피압지하수위, 풍화암반 파쇄대의 투수성 그리고 연약층의 풍화정도를 고려한 간극수압 계측의 실내모형 실험이다. 제3기층 붕괴형과 붕괴성 붕괴형의 모형으로 피압지하수 상태에서 filter의 투수성에 따른 연약층내에서의 간극공기압 및 간극수압의 반응을 측정하였다. 간극압의 반응양상에 있어서 제3기층 붕괴형은 시간 변화에 따라 반응양상이 계단형(step type)으로 나타났고 붕괴성 붕괴형은 파형(wave type)으로 나타났다. 간극수압 반응율은 제3기층 붕괴형이 붕괴성 붕괴형보다 크며, 연약층의 풍화도의 증가에 따라 간극수압 반응율은 감소하였다.

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Tertiary denitrification of the secondary effluent in biofilters packed with composite carriers under different carbon to nitrogen ratios

  • Shi, Yunhong;Wei, Nan;Wu, Guangxue
    • Environmental Engineering Research
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    • 제21권3호
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    • pp.311-317
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    • 2016
  • A new type of biofilter packed with composite carriers was designed for tertiary denitrification of the secondary effluent with removal of both oxidized nitrogen and suspended solids (SS). At the empty bed residence time of 15 min and organic carbon to nitrate nitrogen ($C/NO_3-N$) ratios of 2, 1.5 and 1 g/g, the removal percentage of $NO_3-N$ was 67%, 58% and 36% in the ethanol biofilter, and was 61%, 43% and 26% in the acetate biofilter, respectively. The biofilters packed with composite carriers removed SS effectively, with the effluent turbidity in both biofilters of less than 3 NTU. During the operating cycle between the biofilter backwashings, the $NO_3-N$ removal percentage decreased initially after backwashing, and then gradually increased. Under $C/NO_3-N$ ratios of 2, 1.5 and 1 g/g, the $NO_3-N$ reduction rate was 1.75, 1.04 and $0.68g/m^2/d$ in the ethanol biofilter, and was 1.56, 1.07 and $0.76g/m^2/d$ in the acetate biofilter, respectively. In addition, during denitrification, the ratio of the consumed chemical oxygen demand to the removed $NO_3-N$ was 5.06-8.23 g/g in the ethanol biofilter, and was 4.26-8.6 g/g in the acetate biofilter.

임상 전문간호사 역할 기대 조사;A 병원을 중심으로 (A Investigative Study of Role Expectation on the Clinical Nurse Specialist)

  • 임경춘;박광옥;김복자
    • 간호행정학회지
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    • 제3권1호
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    • pp.65-82
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    • 1997
  • The purpose of this study was to investigate the role expectation of Clinical Nurse Specialist(CNS) in A tertiary-affiliated hospital in Seoul. Data were surveyed from Jul. 8, to Jul. 20, 1996. 74 medical doctors and 119 nurses participated in this survey. For data analysis, SPSS/PC+ program was used: ${\chi}2-test$, t-test, ANOVA. The difference was analyzed by the subjects' position and department. The results of this study were summarized as follows: 1. The perception about the CNS system : Most of the subjects of study perceived that the introduction of CNS system was needed. And the introduction time of CNS system was demanded as fast as possible, or after special preparation. 2. The comparison of the need for the subroles of the CNS in A tertiary-affiliated hospital : The need for the subroles(0=not known, 1=not needed to 4=absolutely essential) was significantly different between medical doctors and nurses. The total mean scores for degree of need for each subole were as follows: Education 3.37, Consultant 3.34, Researcher 3.29, Direct care provider 2.86. 3. The comparison of the percent of time spent in A tertiary-affiliated hospital : The percent of time spent was significantly different between medical doctors and nurses. The total mean percent of time spent in the five subroles was as follows: Direct care provider 34.9%, Educator 23.9%, Researcher 18.9%, Consultant 12.8%, and Management/Change agent 9.5% According to the study results, suggestions were made: 1. Further study for the need of the CNS role as direct care provider is needed, after correcting the items within the narrow scope in some clinical department. 2. Development of the detail roles for the extent of autonomy is needed, and validity should be tested. And then they will be used for the basic data of the role development of the CNS.

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Tertiary Structure of Ginsenoside Re Studied by NMR Spectroscopy

  • Kang, Dong-Il;Jung, Ki-Woong;Kim, Seoung-Keum;Lee, Sung-Ah;Jhon, Gil-Ja;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • 제28권12호
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    • pp.2209-2213
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    • 2007
  • Ginseng has long been used as a traditional medicine in Asian countries including Korea and China. In recent years, it has been reported that the biological activities of ginseng are due to its active components, ginsenosides. Ginsenosides are represented by triterpenes of the dammarane type. Ginsenoside Re consists of two glucose rings, one rhamnose ring, and the triterpene ring. In the present study ginsenoside Re has been isolated from the Korean ginseng (Panax ginseng) and the tertiary structure has been determined using NMR spectroscopy. Flexibilities around each linkages described by seven torsion angles were considered. The structures of ginsenoside Re obtained by NMR spectroscopy show the rigidity around the glucopyranosyl ring II and alkene side chain. The dihedral angles of φ5, φ6, φ7 are about 150o, 50o and 45o, respectively. In addition, flexibility exists around rhamnopyranosyl and glucopyronosyl moiety. The linkage around the rhamnopyranosyl and glucopyranosyl ring I, are divided into three groups. This flexibility seems to play important role in regulation of the hydrophobic surface exposed to the solvent. Because of the growing need for the structural determination of ginsenoside, this result can help to understand their well-accepted pharmacological effects of ginsenoside Re.

울산지역 제3기 정자분지의 도로사면 지반특성 (Geotechnical Characteristics of Cut Slope in Tertiary Jungja Bain, Ulsan area)

  • 김승현;구호본;이정엽;이종현;박성규;김관영
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.107-112
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    • 2005
  • Road is built continuously along with development of industry and cut slope is happened necessarily in road construction. Geoengineers are executing cut slope stability analysis considering various cut slope condition such as topography, geology, hydraulic condition and so on. The Tertiary Jungja Basin is located in the southeastern coastal area of the Korea Peninsula. Jungja Basin area is created by geotectonic movement of the plate after Early Miocene epoch. The northwestern and southwestern boundary of the basin is fault zone. The Basement rock is hornfels (Ulsan Formation). Basin-fills consist of extrusive volcanic rock(Tangsa Andesites), unconsolidated fluviatile conglomerate(Kangdong Formation) and shallow brackish-water sandstone(Sinhyun Formation). The characteristics of cut slopes in this area is different with cut slopes in the other site. Soil layers in this area is unconsolidated sediments and is not formed the weathering and erosion of the rock. So, the depth of soil layer is very thick. Faults of this area are northwest-southeast and northeast-southwest direction. Expandible clay mineral as smectite, chlorite et al. detected from fault gouge using XRD. Therefore, Jungja Basin area must consider the characteristics of the faults and soil layers thickness necessarily cut slopes stability analysis.

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선택진료제도 개편에 대한 중요도-성취도 분석(IPA) - 서울시내 상급종합병원 의료종사자 인식을 중심으로 - (An Importance-Performance Analysis of the Healthcare Reform on a Doctor-Designation System - Focused on the Perception of Medical Providers' at Tertiary Hospital in Seoul -)

  • 박혜진;김효정;김영훈
    • 한국병원경영학회지
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    • 제23권1호
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    • pp.28-40
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    • 2018
  • Purpose: The purpose is to understand the perception of medical providers at tertiary hospitals in Seoul on the importance-performance of the reform on a doctor-designation system, and to provide the policy suggestion of the perception on such a system. Methodology: To achieve the purpose, this study utilized structured survey tools to conduct a questionnaire survey of nursing, administrative and medical technology professionals at six tertiary hospitals in Seoul. An importance-performance analysis was utilized for an analysis that showed the perception of the reform on a doctor-designation system. Findings: First, it was identified that those medical providers had the highest perception of the importance about the performance of the reform on a doctor-designation system. Second, according to the result of action grid of an importance-performance analysis (IPA), it can be identified that in the 2nd stage of 'Concentrate here' included are the items as to design and effect of medical care quality and subsidies & patient infection and safety and control fees, effect of income security of the method for compensating for loss established by the government and offering sufficient information on general medical services and doctor-designation medical services. In the 1st stage of 'Keep up the Good Work', and the 2nd stage of 'Concentrate here' included is the item as to the performance of patients of the reform on a doctor designation system. Practical Implications: There could be identified the effect of the reform bill on the perception of medical providers. It is expected that a better environment would be provided for patients to use a hospital and for medical providers to offer medical services, if the goverment makes efforts to improve methods for compensating for loss and continuous monitoring of the performance of patients.

The Prevalence and Risk Factors of Latent Tuberculosis Infection among Health Care Workers Working in a Tertiary Hospital in South Korea

  • Park, Jae Seuk
    • Tuberculosis and Respiratory Diseases
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    • 제81권4호
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    • pp.274-280
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    • 2018
  • Background: The risk of tuberculosis (TB) infection among health care workers (HCWs) is higher than as noted among workers in the general population. The prevalence and risk factors of TB infection among HCWs were assessed in a tertiary hospital in South Korea, resulting in a conclusion of an intermediate TB burden within the country. Methods: This cross-sectional study enrolled HCWs who underwent a QuantiFERON-TB Gold In-Tube (QFT-GIT) test to detect the presence of a latent TB infection (LTBI), in patients admitted to a tertiary hospital in South Korea in 2017. The departments of the hospital were divided into TB-related and TB-unrelated departments, which were based on the risk of exposure to TB patients. In this sense, the risk factors for LTBI, including current working in the TB-related departments, were analyzed. Results: In this case, a total of 499 HCWs (54 doctors, 365 nurses and 80 paramedical personnel) were enrolled in this study. The median age of the subjects was 31 years (range, 20-67 years), 428 (85.8%) were female, and 208 (41.7%) were working in the TB-related departments. The prevalence of LTBI was 15.8% based on the QFT-GIT. Additionally, the prevalence of experience of exposure to pre-treatment TB patents was higher among HCWs working in the TB-related departments, than among HCWs working in the TB-unrelated departments (78.8% vs. 61.9%, p<0.001). However, there was no significant difference in the prevalence of LTBI between the two groups (17.3% vs. 14.8%, p=0.458). On a review of the multivariate analysis, only the factor of age was independently associated with an increased risk of LTBI (p=0.006). Conclusion: Broadly speaking, the factor of age was associated with an increased risk of LTBI among the HCWs in South Korea. However, those workers current working in the TB-related departments was not associated with an increased risk of LTBI.