• 제목/요약/키워드: Ko-loading

검색결과 201건 처리시간 0.026초

토목섬유를 이용한 임도 노면의 안정성 예비 분석 (Preliminary Analysis of Stabilization of Forest Road Surface Using Geosynthetics)

  • 이관희;오세욱;고치웅;김동근
    • 한국환경복원기술학회지
    • /
    • 제18권6호
    • /
    • pp.51-60
    • /
    • 2015
  • This study conducted shear strength test and plate bearing test to look into the characteristics of bearing capacity using geosynthetics case on forest road surface. The shear strength test showed that the internal friction angle at the time when geosynthetics was used was measured larger on average than that in the unreinforced case. Therefore, using geosynthetics case produced more bearing capacity reinforcement effect. The result from the comparison test of internal friction angle by geosynthetics type revealed that the internal friction angle at the time when geotextile case was used was measured larger. That was attributable to the difference between the area of the total cross section of geotextile made in type of non-woven fabric and its material. Plate bearing test showed that the settlement at the time when geosynthetics was used was measured smaller than that in the unreinforced case. Therefore, using geosynthetics produced more bearing power reinforcement effect. The result from the comparison test showed that geogrid case was measured smaller than geotextile case. Henceforth, It is seemed that it will be necessary to keep studying the reinforcement engineering and process of forest road surface which fits the characteristics and conditions of geosynthetics to prevent forest road demage.

인체 흉추 해면골의 영역별 형태학적 및 기계적 특성 연구 (Regional Morphological and Mechanical Characteristics in the Human Thoracic Vertebral Trabecular Bones)

  • 이태우;우대곤;고창용;김한성
    • 한국정밀공학회지
    • /
    • 제27권1호
    • /
    • pp.134-141
    • /
    • 2010
  • This study analyzed the regional morphological and mechanical characteristics of vertebrae by using micro-computed tomography (micro-CT) and micro finite element analysis (FEA). For the present study, the $12^{th}$ human thoracic vertebral bones (an 85-years female and a 48-years male) were used. These were scanned by using micro-CT. Structural parameters were evaluated from the acquired 20 image data for fifteen $4{\times}4mm^2$ regions (five regions in respective layers of superior, middle and inferior part) in the thoracic vertebral trabecular bones. $4{\times}4{\times}4mm^3$ cubic finite element models of each regions were created at $70{\mu}m$ voxel resolution to investigate effective modulus ($E^+$). The present study indicated that there were significant differences in morphological and elastic mechanical characteristics of each region. There are close relationship between effective modulus and structural model index (SMI) in the bone of the 48-years male and between effective modulus and bone volume fraction (BV/TV) in the bone of the 85-years female. In addition, the effective modulus of central regions is about 80% stiffer than that of lateral regions at transverse plane. These findings may be likely to explain the previous result that a change of loading distribution of the vertebral trabecular bones is caused by spinal curvature and nucleus pulpous degeneration of the intervertebral disc.

다양한 아미노실란을 이용한 이산화탄소 흡착제 합성 및 흡착 특성 (Synthesis of CO2 Adsorbent with Various Aminosilanes and its CO2 Adsorption Behavior)

  • 전재완;고영수
    • 공업화학
    • /
    • 제27권1호
    • /
    • pp.80-85
    • /
    • 2016
  • 넓은 비표면적과 큰 기공 부피를 갖는 실리카에 다양한 아미노실란 화합물을 in-situ 중합법을 통해 기능화 후 이산화탄소 흡착 특성을 확인하였다. 이산화탄소 흡착 기능기로 아민기가 포함된 아미노실란 화합물이 사용되었다. 흡착제의 흡착 특성 분석을 위해 질소 흡 탈착 실험과 원소분석, in situ FT-IR, TGA를 이용하였다. 흡착제 합성 전후를 비교하였을 때 폴리아미노실란이 기능화되면 표면적과 기공부피 및 크기가 감소하였으며 실리카 기공 부피의 70%에 해당하는 폴리아미노실란 화합물을 기능화 시켰을 경우 기공 부피의 100% 기능화 보다 이산화탄소 흡착능이 향상되었다. 흡착 온도를 비교하며 $30^{\circ}C$보다 $75^{\circ}C$에서 폴리아미노실란 화합물의 열팽창과 자유부피 증가로 흡착능이 증가하였고, 2NS/NPS-2의 경우 기공 부피 70% 기능화와 흡착 온도 $75^{\circ}C$에서 9.2 wt%의 높은 $CO_2$ 흡착능을 보였다.

질소 동위원소비를 이용한 관행농업과 유기농업에서의 질산태 질소 오염원 구명 (Investigation of Nitrate Contamination Sources Under the Conventional and Organic Agricultural Systems Using Nitrogen Isotope Ratios)

  • 고한종;최홍림;김기연
    • Journal of Animal Science and Technology
    • /
    • 제47권3호
    • /
    • pp.481-490
    • /
    • 2005
  • Nitrate contamination in water system is a critical environmental problem caused by excessive application of chemical fertilizer and concentration of livestock. In order to prevent further contamination, therefore, it is necessary to understand the origin of nitrate in nitrogen loading sources and manage the very source of contamination. The objective of this study was to examine the nitrate contamination sources in different agricultural system by using nitrogen isotope ratios. Groundwater and runoff water samples were collected on a monthly basis from February 2003 to November 2003 and analyzed for nitrogen isotopes. The nitrate concentrations of groundwater in livestock fanning area were higher than those in conventional and organic fanning area and exceeded the national drinking water standard of 10mg N/ l. The ${\delta}^{15}N$ranges of chemical fertilizer and animal manure were - 3.7${\sim}$+2.3$\textperthousand$ and +12.5${\sim}$26.7$\textperthousand$, respectively. The higher ${\delta}^{15}N$ of animal manure than those of chemical fertilizer reflected isotope fractionation and volatilization of '''N. The different agricultural systems and corresponding average nitrate concentrations and ${\delta}^{15}N$ values were: conventional farming, 5.47mg/e, 8.3$\textperthousand$; organic fanning, 5.88mg/e, 10.1$\textperthousand$; crop-livestock farming, 12.5mg/e, 17.7%0. These data indicated that whether conventional or organic agriculture effected groundwater and runoff water quality. In conclusions, relationship between nitrate concentrations and ${\delta}^{15}N$ value could be used to make a distinction between nitrate derived from chemical fertilizer and from animal manure. Additional investigation is required to monitor long-term impact on water quality in accordance with agricultural systems.

통증 자가 조절법을 이용한 상복부와 하복부 수술 후 통증의 비교 (Comparative Study of Postoperative Pain in Lower and Upper Abdominal Surgery Using Patient-Controlled Analgesia)

  • 고성훈;김동찬;이준례;한영진;최훈
    • The Korean Journal of Pain
    • /
    • 제13권2호
    • /
    • pp.208-212
    • /
    • 2000
  • Background: We studied 250 patients who received intravenous patient-controlled analgesia (PCA) after lower and upper abdominal surgery to evaluate pain relief, analgesic consumption, patient's mood and side effects. Methods: We made total 60 ml of analgesic mixture with morphine 60 mg, ketorolac 180 mg, droperidol 5 mg and normal saline. Loading and bolus dose and lockout interval were 0.05 ml/kg, 1.0 ml and 7 min, respectively. The duration of operation and the length of skin incision were recorded. Visual analog scale (VAS) pain and mood scores, cumulative analgesic consumption, and incidence of side effect were evaluated. Results: In the upper abdominal surgery group (Group 2), the duration of operation and length of skin incision were longer than Group 1. The average postoperative pain scores at 6, 24, and 48 hours in lower (Group 1) vs upper (Group 2) abdominal surgery were $4.3{\pm}2.1$ vs $4.7{\pm}2.4$, $3.3{\pm}1.9$ vs $4.3{\pm}2.8$, and $2.4{\pm}2.7$ vs $3.2{\pm}2.1$, respectively. There were no significant differences in the cumulative analgesic consumption and number of analgesic demands and at 6, 24, 48 hours after the operation between two groups. Group 2 patients required significantly longer pain control using PCA as compared to Group 1 patients. There were no significant differences in the incidence of side effects between the two groups. Conclusions: There was little difference in postoperative pain after lower and upper abdominal surgery.

  • PDF

집합 기반 POI 검색을 이용한 문장 유사도 측정 기법 (Sentence Similarity Measurement Method Using a Set-based POI Data Search)

  • 고은별;이종우
    • 정보과학회 컴퓨팅의 실제 논문지
    • /
    • 제20권12호
    • /
    • pp.711-716
    • /
    • 2014
  • 최근 논문 표절 논란과 지능형 텍스트 검색서비스에 대한 관심이 증가하면서 문장 유사도 측정의 필요성이 증가하고 있다. n-gram, 편집거리, LSA 등 기존의 다양한 방향으로 선행 연구가 있었지만 각 기법마다 장단점이 존재한다. 본 논문에서는 집합 기반 POI 검색 기법을 이용한 새로운 방향의 문장 유사도 측정 기법을 제안한다. 집합 기반 POI 검색 기법은 하드매칭에 비해 단어의 도치, 누락, 삽입, 변경에 현저한 성능 향상을 보인다. 이 기법을 이용하면 보다 정확하고 빠른 문장 유사도 측정이 가능하다. 제안하는 기법은 기존 집합 기반 POI 검색 기법의 데이터 로딩 알고리즘과 텍스트 검색 알고리즘을 변형하고 어절 연산 알고리즘을 추가하여 두 문장의 유사도를 백분율로 표현한다. 실험을 통해 본 논문에서 제시하는 기법이 정확도와 속도에서 n-gram과 기존 집합 기반 POI 검색 기법에 비해 우수함을 확인하였다.

Intravenous levetiracetam versus phenobarbital in children with status epilepticus or acute repetitive seizures

  • Lee, Yun-Jeong;Yum, Mi-Sun;Kim, Eun-Hee;Ko, Tae-Sung
    • Clinical and Experimental Pediatrics
    • /
    • 제59권1호
    • /
    • pp.35-39
    • /
    • 2016
  • Purpose: This study compared the efficacy and tolerability of intravenous (i.v.) phenobarbital (PHB) and i.v. levetiracetam (LEV) in children with status epilepticus (SE) or acute repetitive seizure (ARS). Methods: The medical records of children (age range, 1 month to 15 years) treated with i.v. PHB or LEV for SE or ARS at our single tertiary center were retrospectively reviewed. Seizure termination was defined as seizure cessation within 30 minutes of infusion completion and no recurrence within 24 hours. Information on the demographic variables, electroencephalography and magnetic resonance imaging findings, previous antiepileptic medications, and adverse events after drug infusion was obtained. Results: The records of 88 patients with SE or ARS (median age, 18 months; 50 treated with PHB and 38 with LEV) were reviewed. The median initial dose of i.v. PHB was 20 mg/kg (range, 10-20 mg/kg) and that of i.v. LEV was 30 mg/kg (range, 20-30 mg/kg). Seizure termination occurred in 57.9% of patients treated with i.v. LEV (22 of 38) and 74.0% treated with i.v. PHB (37 of 50) (P=0.111). The factor associated with seizure termination was the type of event (SE vs. ARS) in each group. Adverse effects were reported in 13.2% of patients treated with i.v. LEV (5 of 38; n=4, aggressive behavior and n=1, vomiting), and 28.0% of patients treated with i.v. PHB (14 of 50). Conclusion: Intravenous LEV was efficacious and safe in children with ARS or SE. Further evaluation is needed to determine the most effective and best-tolerated loading dose of i.v. LEV.

근해운송시스템의 기술 분야별 개발 현황 및 시사점 (Recent Development in Technologies for Short Sea Shipping and its Implications)

  • 서대원;고정오;이승희
    • 한국항해항만학회지
    • /
    • 제36권10호
    • /
    • pp.883-888
    • /
    • 2012
  • 최근 아시아의 물류산업은 중국경제의 급부상과 함께 빠른 속도로 성장하고 있으며, 전 세계적으로 물동량이 계속적으로 증가하고 있는 상황에서 물류비용 절감을 위하여 다양한 연구가 활발히 수행중이다. 근해운송시스템은 연안해운을 중심으로 두 가지 이상의 수송연계 수단을 효율적으로 이용하여, 국제간 고부가 가치 물류 시스템을 창출하는 시스템으로써 유럽에서 상당한 성과를 올리고 있다. 따라서 우리나라에 알맞은 근해운송시스템을 도입하기 위해서는 효율적인 선박, 항만, 컨테이너 하역 및 운송 장비, 터미널 운영 및 관리시스템 기술, 화물정보 추적 및 통신 분야의 요소 기술 개발이 요구된다. 본 논문에서는 현 단계의 요소기술 현황을 살펴보고, 앞으로 나아가야 할 공학적 기술에 대한 시사점을 제시하고자 한다.

치자의 스트레스 관련 생리 활성: 홍삼과의 비교 연구 (Stress Related Activities of Gardenia Jasminoides: Comparative Study with the Effects of Red Ginseng)

  • 고홍숙;이금선;블랜딜;박형근;유구용;임동술;정인경;오세관;정재훈
    • 약학회지
    • /
    • 제49권4호
    • /
    • pp.291-298
    • /
    • 2005
  • Gardenia Jasminoides(GJ) is traditionally used for treatment of hepatic disease, insomnia, anxiety, and inflammatory disease. The aim of this study is to examine effects of GJ extract in response to stress. Animals of the normal group were not exposed to any stress and the control group were exposed to stress. The rats of the Ginseng and GJ supplementary group were orally administered once a day with 100mg of red ginseng extract, 100mg of GJ extract/kg body weight. The mice were given water containing 200mg of red ginseng extract, 200mg of GJ extract/100ml potable water. Animals were given supplements for 7 days without stress, and then were given supplements for 5 days with restraint and electroshock stress. After loading final stress, we examined stress related behavioral changes of experimental animals and measured the levels of blood corticosterone. GJ-supplementation partially blocked the stress effect on locomotion and elevated plus maze test in rats, and also partially blocked stress-induced behavioral changes such as freezing, burrowing, face-washing, smelling and rearing behavior in rats. The effect was almost equipotent to Ginseng's effect. GJ-supplementation didn't influence on fatigue related behavior or physical stress resistance. GJ-supplementation decreased the levels of blood corticosterone which is increased by stress in rats. These results suggest that GJ protects partially the living organism from stress attack and it has the potential to be used as a functional material to alleviate stress response.

Leflunomide로 치료중인 류마티스 관절염 환자에서 발생한 간질성 폐렴 1예 (A Case of Interstitial Pneumonitis in a Patient with Rheumatoid Arthritis Treated with Leflunomide)

  • 신아영;김승수;김경희;주일남;고혁재
    • Tuberculosis and Respiratory Diseases
    • /
    • 제66권6호
    • /
    • pp.477-481
    • /
    • 2009
  • Leflunomide는 항류마티스 약제로 최근 류마티스 관절염 치료에 효과적으로 사용되고 있다. 최근 본 약제로 인한 간질성 폐렴이 일본과 한국에서 서구에서보다 많이 보고되고 있으며 종종 사망하는 경우도 보고되고 있다. 저자들은 25세 여자에서 Methotrexate와 Leflunomide의 병합요법 중 발생한 간질성 폐렴을 진단하였고 Methylprednisolone과 Cholestyramine을 조기 투여하여 효과적으로 치료하였기에 문헌 고찰과 함께 보고하는 바이다.