• 제목/요약/키워드: Covering methods

검색결과 531건 처리시간 0.03초

잔대 종자 펠렛처리가 종자 발아에 미치는 영향 (Effect of Pelleting Treatment on Seed Germination in Adenophora triphylla)

  • 임동현;남주희;김종혁;이민주;노일래
    • 한국약용작물학회지
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    • 제28권2호
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    • pp.128-135
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    • 2020
  • Background: Sowing seeds of Adenophora triphylla is known to be difficult owing to their small size and irregular seed shape. Therefore, this study was conducted to develop a seed pelleting technique to save labor during sowing. Methods and Results: To identify the optimal germination temperature for A. triphylla seeds, the temperature range was set from 17℃ to 32℃. Germination surveys were conducted in plastic greenhouse conditions in March, April, and May to determine the appropriate sowing time. The optimal germination temperature for A. triphylla seeds was 29℃ and May was the optimal sowing time in plastic greenhouse conditions. Covering materials for seed pelleting used talc (T), kaolin (K), calcium carbonate (C), and vermiculite (V). The pellet binder used agar (A), pectin, xanthan gum, polyvinyl alcohol (PVA), and sodium alginate (S). The best suited treatment mixture were the best suited in kaolin / calcium carbonate / vermiculite (KCV), talc / calcium carbonate / vermiculite (TCV) mixture treatment for covering material, and sodium alginate (S), agar (A) as pellet binder, respectively. The germination rate was the best in TCV mixed with S. Conclusion: The mixture of TCV (2 : 1 : 3) + 1.5% S (TCVS), was found to be the best pelleting materials for A. triphylla seeds, and seed pelleting can be labor-saving during sowing.

성복토용 순환잔골재의 pH 저감방법에 관한 연구 (Study on pH Reducing Method of Recycled Fine Aggregate for Embanking or Covering)

  • 한민철;한동엽
    • 한국건축시공학회지
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    • 제17권1호
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    • pp.23-30
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    • 2017
  • 순환골재가 복토 및 성토용으로 활용되는 경우 순환골재 표면의 미수화 시멘트로부터 발생하는 높은 pH의 침출수는 환경에 큰 영향을 주는 요소이다. 본 연구에서는 이러한 높은 pH의 침출수를 방지하기 위해 순환골재의 효율적인 알칼리 제거 방안에 대해 실험적으로 비교분석 하였다. 실험결과 순환골재의 높은 알칼리성을 감소시키기 위해서는 단순 야적 및 물을 이용한 씻기 방법보다는 비료를 사용한 처리방법이 가장 유리한 것으로 나타났다. 또한, 본 연구에서는 비료의 종류인 인산암모늄과 이인산암모늄을 활용하여 순환골재를 중화시켰고 그 결과 약 3주 만에 pH 8의 중성에 가까운 순환잔골재를 얻을 수 있었다. 본 연구를 통해 순환골재를 토공사용으로 사용할 때에 보다 환경에 안전한 지속가능한 재료로서 활용하는 데에 기여할 것으로 예상한다.

Influence of thickness and incisal extension of indirect veneers on the biomechanical behavior of maxillary canine teeth

  • Costa, Victoria Luswarghi Souza;Tribst, Joao Paulo Mendes;Uemura, Eduardo Shigueyuki;de Morais, Dayana Campanelli;Borges, Alexandre Luiz Souto
    • Restorative Dentistry and Endodontics
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    • 제43권4호
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    • pp.48.1-48.13
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    • 2018
  • Objectives: To analyze the influence of thickness and incisal extension of indirect veneers on the stress and strain generated in maxillary canine teeth. Materials and Methods: A 3-dimensional maxillary canine model was validated with an in vitro strain gauge and exported to computer-assisted engineering software. Materials were considered homogeneous, isotropic, and elastic. Each canine tooth was then subjected to a 0.3 and 0.8 mm reduction on the facial surface, in preparations with and without incisal covering, and restored with a lithium disilicate veneer. A 50 N load was applied at $45^{\circ}$ to the long axis of the tooth, on the incisal third of the palatal surface of the crown. Results: The results showed a mean of $218.16{\mu}strain$ of stress in the in vitro experiment, and $210.63{\mu}strain$ in finite element analysis (FEA). The stress concentration on prepared teeth was higher at the palatal root surface, with a mean value of 11.02 MPa and varying less than 3% between the preparation designs. The veneers concentrated higher stresses at the incisal third of the facial surface, with a mean of 3.88 MPa and a 40% increase in less-thick veneers. The incisal cover generated a new stress concentration area, with values over 48.18 MPa. Conclusions: The mathematical model for a maxillary canine tooth was validated using FEA. The thickness (0.3 or 0.8 mm) and the incisal covering showed no difference for the tooth structure. However, the incisal covering was harmful for the veneer, of which the greatest thickness was beneficial.

Influence of Helicobacter pylori Infection on Endoscopic Findings of Gastric Adenocarcinoma of the Fundic Gland Type

  • Ishibashi, Fumiaki;Fukushima, Keita;Ito, Takashi;Kobayashi, Konomi;Tanaka, Ryu;Onizuka, Ryoichi
    • Journal of Gastric Cancer
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    • 제19권2호
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    • pp.225-233
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    • 2019
  • Purpose: Gastric adenocarcinoma of the fundic gland type (chief cell predominant type) (GA-FG-CCP) was first reported as a rare adenocarcinoma found in the normal fundic mucosa. Recent studies have proposed the possibility that GA-FG-CCPs were also generated in the atrophic mucosa after Helicobacter pylori (HP) eradication therapy. However, little is known on the endoscopic findings of GA-FG-CCP generated in the atrophic mucosa due to its extreme rarity. Materials and Methods: A total of 8 patients who underwent endoscopic submucosal resection and were diagnosed with GA-FG-CCP generated in the HP-uninfected mucosa (4 cases, HP-uninfected group) or HP-eradicated atrophic mucosa (4 cases, HP-eradicated group) were retrospectively analyzed, and their endoscopic findings, including magnifying endoscopy with narrow band imaging (M-NBI), and pathological features were compared. Results: While GA-FG-CCPs in the 2 groups displayed similar macroscopic appearance, M-NBI demonstrated that characteristic microvessels (tapered microvessels like withered branches) were specifically identified in the HP-eradicated group. Pathological investigation revealed that a decreasing number of fundic glands and thinned foveolar epithelium covering tumor ducts were thought to lower the thickness of the covering layer over tumor ducts in the HP-eradicated group. Moreover, dilation of vessels just under the surface of the lesions contributed to the visualization of microvessels by M-NBI. Conclusions: The change in background mucosa due to HP infection influenced the thickness of the covering layer over the tumor ducts and M-NBI finding of GA-FG-CCP.

바닥충격음 저감방안에 따른 성능평가 (Evaluation of Floor Impact Sound Performance according to the Reduction Methods)

  • 김경우;최경석;최현중;양관섭
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.131-136
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    • 2004
  • Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. The character and level of impact noise generated depends on the object striking the floor, on the basic structure of the floor, and on the floor covering. This study base on the evaluate of isolation performance of impact sound according to the impact noise reduction methods. Reduction methods consist of four ways. First way is increase thickness of bare floor and other ways are using the soft coverings on the floor and ceiling assembles. Last way is make floating floor with shock absorbing materials.

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바닥충격음 저감방안에 따른 성능평가 (Evaluation of Floor Impact Sound Performance according to the Reduction Methods)

  • 최경석;최현중;양관섭;김경우
    • 한국소음진동공학회논문집
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    • 제14권9호
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    • pp.811-818
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    • 2004
  • Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. The character and level of impact noise generated depends on the object striking the floor, on the basic structure of the floor, and on the floor covering. This study base on the evaluate of isolation performance of impact sound according to the impact noise reduction methods. Reduction methods consist of four ways. First way is increase thickness of bare floor and other ways are using the soft coverings on the floor and ceiling assembles. Last way is make floating floor with shock absorbing materials.

최적부하제한방식의 결정과 운용에 관한 연구 (A Study on the Determination and Application of the Optimum Load Shedding Schemes)

  • Song, Kil-Yeong
    • 대한전기학회논문지
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    • 제34권1호
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    • pp.29-37
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    • 1985
  • During Severe emergencies which result in the case of outage of large generator units, an automatic underfrequency protection scheme can prevent the system frequency from decaying and improve the system stability. This paper presents methods and results of a study on the optimum load shedding scheme which covering as follows. 1) Detail representation of governor model 2) Determination of optimum load shedding amount 3) Selection of action time settings of UFR 4) Comparsson of load shedding programs By this study, the optimum system operating method was recommended for reliable operation of power system.

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보온피복방법이 난방비와 토마토 생육 및 수량에 미치는 영향 (Effects of Covering Methods for Insulation on Heating Cost, Growth and Yield of Tomato in Greenhouse)

  • 권준국;최영하;박동금;이재한
    • 한국생물환경조절학회:학술대회논문집
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    • 한국생물환경조절학회 1999년도 정기총회 및 학술논문발표요지
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    • pp.58-61
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    • 1999
  • 농가에서 주로 사용하고 있는 플라스틱하우스의 보온방법은 부직포로 된 보온 커텐을 2중 혹은 3중으로 설치하는 것이 대부분이다. 근래에는 영남 남부지역의 고추재배 농가를 중심으로 단동형 하우스에 다겹보온시트나 보온덮개를 외면피복하여 보온성을 높이려는 방법이 증가추세에 있다. 본 실험에서는 다겹보온시트의 설치방법에 따른 보온특성과 토마토의 생육 및 수량에 미치는 영향을 구명하고자 수행하였다. (중략)

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우리나라 IMF원인에 관한 연구:Mind Mapping을 통한 시스템 사고 (A Study for Causes of the Korean IMF Stand-by arragement : System Thinking Approach Using Mind Mapping)

  • 전기정;김준성;이상은
    • 한국시스템다이내믹스연구
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    • 제1권1호
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    • pp.81-102
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    • 2000
  • After the crisis of foreign troubles, various researchers are analyzing the causes of IMF stand-by arrangement in their own ways. But, most research have been lacking in covering the overall aspects of the causes which IMF stand-by arrangement results from. This paper extracts the reasons of IMF stand-by arrangement using Mind Mapping methods and intends to draw up cause & effect map.

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지중 케이블 시스템에서 본딩방식의 혼용으로 인한 영향 (The Effect of Different Boding Methods in Under Ground Cable System)

  • 김정년;하체웅;이수길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.352-355
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    • 2001
  • 국내에서 CCPU(Cable Covering Protection Unit)의 결선방식은 97년 이전에는 대지간 방식을 취하였고, 97년 이후에는 교락 비접지 방식을 채택하여 적용중이다. 따라서 국내 선로 중에 97년 이전 준공되어 97년 이후에 증설한 선로에서는 CCPU의 연결방식이 대지간 및 교락 비접지 방식이 혼용되어 사용되어 왔다. 본 논문에서는 CCPU의 결선방식이 혼용된 선로에서 문제점을 규명하고 개선안을 제시하였다.

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