• Title/Summary/Keyword: form oil

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Dynamic Modeling and Manipulability Analysis of Underwater Robotic Arms (수중로봇팔의 동역학 모델링과 동적 조작도 해석)

  • Jnn Bong-Huan;Lee Jihong;Lee Pan-Mook
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.8
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    • pp.688-695
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    • 2005
  • This paper describes dynamic manipulability analysis of robotic arms moving in viscous fluid. The manipulability is a functionality of manipulator system in a given configuration under the limits of joint ability with respect to the task required to be performed. To investigate the manipulability of underwater robotic arms, a modeling and analysis method is presented. The dynamic equation of motion of underwater manipulator is derived based on the Lagrange-Euler equation considering with the hydrodynamic forces caused by added mass, buoyancy and hydraulic drag. The hydrodynamic drag term in the equation is established as analytical form using Denavit-Hartenberg (D-H) link coordination of manipulator. Two analytical approaches based oil manipulability ellipsoid are presented to visualize the manipulability of robotic arm moving in viscous fluid. The one is scaled ellipsoid which transforms the boundary of joint torque to acceleration boundary of end-effector by normalizing the torques in joint space, while the other is shifted ellipsoid which depicts total acceleration boundary of end-effector by shifting the ellipsoid as much as gravity and velocity dependent forces in work space. An analysis example of 2-link manipulator with proposed analysis scheme is presented to validate the method.

Study on Application of Shaft Box type Balcony for Improvement of Ventilation Performance in Apartment (공동주택의 환기성능 개선을 위한 Shaft Box형 발코니의 적용성 검토)

  • Roh, Ji-Woong;Kim, Gon
    • KIEAE Journal
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    • v.7 no.6
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    • pp.3-8
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    • 2007
  • Recently, because of the continuous rise of international oil price, energy saving is strongly demanding. So, Ecological technics of architecture such as use of natural energy have been actively explored in the field of building. In the method of utilizing natural energy, the key point is to saving energy effectively as not lowering the comfort of indoor environment, various systems investigated. Many papers about double skin facade system have been reported, it is announced broadly that the system is very effective in improvement of natural ventilation and indoor thermal environment, and also protecting outdoor sound. The shaft box facade is a special form of box window construction. It consists of a system of box windows with continuous vertical shafts that extend over a number of stories to create a stack effect. The facade layout consists of an alternation of box windows and vertical shaft segments. This research investigated the natural ventilation performance of shaft box type balcony which conform the shaft box type double skin to the exiting balcony construction. First, analyzed various types of exiting apartments, proto-type was decided. By using virtual environment Program, modeling the proto-type, compared the contribution of air temperature and the effect of outdoor air cooling. by this research, we confirmed that shaft box type balcony had many possibility for improvement of indoor environment.

Groundwater Flow Characteristics in Crystalline Rock : Review (결정질암반에서의 지하수유동 연구경향)

  • 김천수
    • The Journal of Engineering Geology
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    • v.1 no.1
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    • pp.137-145
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    • 1991
  • Groundwater flow in fractured rocks generates many challenging problems to scientist and engineers in the projects related to oil and geothermal reservoirs, subsurface contaminations and underground openings. To circumvent these problems, the numerical simulation of groundwater system is used as an established tool in these days. Discrete modelling approach emphasizes geometric parameters, aperture and transport properties of fracture. On the other hand, continuum modelling approach uses the parameters formulated in a way of average hydraulic property. In recent years, the results of field observations from underground opening indicate that groundwater in rock mass flows in a channel form. The channel flow is postulated as the result of the combined effects of geometric pattern and aperture variation.

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Surface Modification of WC-Co and SCM415 by the Ion Bombardment Process of Filtered Vacuum Arc Plasma (자장 여과 아크 이온빔 식각 공정을 이용한 WC-Co 및 SCM415 금속 소재 표면 구조 제어 연구)

  • Lee, Seung-Hun;Yoon, Sung-Hwan;Kim, Do-Geun;Kwon, Jung-Dae;Kim, Jong-Kuk
    • Journal of the Korean institute of surface engineering
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    • v.43 no.2
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    • pp.80-85
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    • 2010
  • The surfaces of WC-Co and SCM415 were etched to form a micro size protrusion for oil based ultra low friction applications using an ion bombardment process in a filtered vacuum arc plasma. WC-Co species showed that a self-patterned surface was available by the ion bombarding process due to the difference of sputtering yield of WC and Co. And the increasing rate of roughness was 0.6 nm/min at -600 V substrate bias voltage. The increasing rate of roughness of SCM415 species was 1.5 nm/min at -800 V, but the selfpatterning effect as shown in WC-Co was not appeared. When the SCM415 species pretreated by electrical discharge machining is etched, the increasing rate of roughness increased from 1.5 nm/min to 40 nm/min at -800 V substrate bias voltage and the uniform surface treatment was available.

ERS SAR observations of the Korean coastal waters

  • Mitnik, Leonid M.;Yoon, Hong-Joo;Dubina, Vyacheslav A.;Kim, Sang-Woo;Kim, Young-Seup
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1124-1126
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    • 2003
  • The processes of regional scales in the East Korean coastal waters were investigated by analysis of the Synthetic Aperture Radar (SAR) images taken by the European Research Satellites ERS-1, ERS-2 and Envisat. More than 500 quick look frames taken in 1991-2003 were examined to detect the frames with clearly surface expressions of oceanic phenomena. 26 ERS-1/2 SAR and 11 Envisat wide swath Advanced SAR (ASAR) frames were selected and obtained from the European Space Agency in a form of the precision high-resolution images. The following oceanic phenomena and processes were evident in the radar imagery through the Korean costal waters: fronts, currents, eddies, internal waves, island and ship wakes, oil pollution, etc. They manifested themselves in the field of sea surface roughness, their scale ranged from several tens meters to about 100 km. The most common morphology of these phenomena was a series of contrast dark or light curvilinear lines and bands. The joint analysis of the discussed SAR images with other satellite and in situ data supported and enhanced our interpretation of SAR signatures.

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Food of Maghreb -Algerian food in particular- (마그레브(Maghreb)의 식문화 -알제리아를 중심으로-)

  • Chun, Hui-Jung
    • Journal of the Korean Society of Food Culture
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    • v.11 no.5
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    • pp.651-661
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    • 1996
  • Algeria is located at the Mediterranean coast of north Africa, 90% of its population is concentrated in the coastal area which is mainly devoted to agriculture. Highland steppe and vast desert climate have determined its food culture. Long arab domination has influenced food of Algeria which has also undergone certain impact of Spanish, Turkish and French occupation. A variety of agricultural products, vegetables, fruits, spices and herbs have determined cooking method and food combination of Algeria. It use neither pork nor alcohol. Its main food consists of bread made from wheat flour and couscous cooked with semoule, Mechuwi, roast lamb and chorba, mixed soup are also typical foods of this region. For climatic reason lamb and chicken are prefered. Energy efficient method is applied to cooking through using oil for saute and water for boiling. Under european influence, Algerian salad used dressing for leaf vegetables, root and other kind vegetables were boiled. Serving with cake and cookies as dessert may possibly be the influence from the French occupation. The cake and cookie are made of wheat flour or other grain flour and take a specific form to be fried sweet with honey. Herbs and spices are widely used in cooking which are easily cultivated in household: mint, basil, rosemary, bayleaf, thyme, sage, fennel, marjoram, coriander, celery. Garlic, onion, piment, red pepper, cinammon are also widely used in an ordinary cooking. Reasonable food combination and economic cooking method could be subject of Algerian food study.

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ERS SAR Observations of the Korean Coastal Waters

  • Yoon, Hong-Joo;Mitnik Leonid M.;Kang, Heung-Soon;Cho, Han-Keun
    • Korean Journal of Remote Sensing
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    • v.23 no.1
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    • pp.65-69
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    • 2007
  • The processes of regional scales in the East Korean coastal waters were investigated by analysis of the Synthetic Aperture Radar (SAR) images taken by the European Research Satellites ERS-1, ERS-2 and Envisat. More than 500 quick look frames taken in 1991-2003 were examined to detect the frames with clearly surface expressions of oceanic phenomena. 26 ERS-1/2 SAR and 11 Envisat wide swath Advanced SAR (ASAR) frames were selected and obtained from the European Space Agency in a form of the precision high-resolution images. The following oceanic phenomena and processes were evident in the radar imagery through the Korean costal waters: fronts, currents, eddies, internal waves, island and ship wakes, oil pollution, etc. They manifested themselves in the field of sea surface roughness, their scale ranged from several tens meters to about 100 km. The most common morphology of these phenomena was a series of contrast dark or light curvilinear lines and bands. The joint analysis of the discussed SAR images with other satellite and in situ data supported and enhanced our interpretation of SAR signatures.

Temperature Effect on Seed Germination and Seedling Growth of Medicinal Umbelliferae Plants

  • Chio, Seong-Kyu;Chon, Sang-Uk
    • Plant Resources
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    • v.3 no.1
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    • pp.66-70
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    • 2000
  • Umbelliferae medicinal crops have low germination under natural condition. Special objective of this study is to investigate morphological characteristics of seeds and effects of environmental factors such as light and temperature on their germination and seedling growth in Umbelliferae plants, using them as oriental medicine materials. Fruits of Umbelliferae are bi-partite type and form 2 seeds. Their oil canals and funiculus or carpaphore has apparently specific shape. Seed shape of Buplerum falcatum, Ligusticum acutilobum and Foeniculum vulgare are oblong, Ledeboutiella seseloides, Angelica dahurica, Angelica gigas elliptic, and Ostericum koreanum ovate. Color of seed coats varied from yellow to dark brown. Seed size was 3.2 to 6.9 mm in length, 1.7 to 4.9 mm in width. One thousand-seed weight of Buplerum falcatum was lowest(at 1,660 mg) and Ledebouriella seseloides and Angelica gigas were relatively highest(at 3,970 mg) having larger size than any others. Optimum temperatures for seed germination and seedling growth ranged from 20 to $25^{\circ}C$ and especially temperature at $25^{\circ}C$ improved seed germinations of Ledebouriella seseloides, Angelica dahurica and Ligusticum acutilobum regardless of light condition.

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Thymol Rich Thymbra capitata Essential Oil Inhibits Quorum Sensing, Virulence and Biofilm Formation of Beta Lactamase Producing Pseudomonas aeruginosa

  • Qaralleh, Haitham
    • Natural Product Sciences
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    • v.25 no.2
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    • pp.172-180
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    • 2019
  • Infections with Pseudomonas aeruginosa are difficult to treat not only because it is often associated with multidrug-resistant infections but also it is able to form biofilm. The aim of this study was to evaluate the antibiofilm and anti-Quorum Sensing (QS) activities of Thymbra capitata essential oils (EOs) against Beta Lactamase (BL) producing P. aeruginosa and the reference strain P. aeruginosa 10145. GC/MS analysis showed that thymol (23.25%) is the most dominant compound in T. capitata EOs. The MICs of T. capitata EOs against P. aeruginosa (BL) and P. aeruginosa 10145 were 1.11%. At sub MIC (0.041, 0.014 and 0.0046%), the EOs of T. capitata remarkably inhibited the biofilm formation of both strains tested and complete inhibition of the biofilm formation was reported at 0.041%. The EOs of T. capitata were found to inhibit the swarming motility, aggregation ability and hydrophobic ability of P. aeruginosa (BL) and P. aeruginosa 10145. Interestingly, the EOs of T. capitata reduce the production of three secreted virulence factors that regulated by QS system including pyocyanin, rhamnolipids and LasA protease. The potent antibiofilm and anti-QS activities of T. capitata EOs can propose it as a new antibacterial agent to control pseudomonas infections.

Systematic Approach to Involving the Tools of Digital Marketing as a Guarantee of the International Business Development

  • Chernenko, Oksana;Kovalchuk, Svitlana;Perevozova, Iryna;Fayvishenko, Diana;Zaburmekha, Yevgena
    • International Journal of Computer Science & Network Security
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    • v.22 no.2
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    • pp.311-317
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    • 2022
  • The research is devoted to the substantiation of the system approach to the involvement of digital marketing tools as a guarantee of international business development. It is proved that digital marketing, as a type of marketing based on the use of digital technologies allows to make a profit, to promote the brand, as well as goods and services in the market. The digital marketing toolkit system is a set of elements with existing relationships that ensure the effectiveness of the entire digital marketing, which in total is greater than its individual components. The implementation of a systems approach involves the implementation of the philosophy of digital marketing in general, its functions in the form of systems analysis, formation of strategic development goals and entry and promotion in the international market, preparation and implementation of tactical and strategic development plans.The use of such digital marketing tools as: content marketing, social media marketing, Email-marketing, targeted advertising, contextual advertising, media advertising, Search Engine Optimization, affiliate programs and the company's website is analyzed in detail.