• Title/Summary/Keyword: impossibility

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FRICTION UNITS FOR THE MOON

  • Drozdov, Yu.N.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.389-396
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    • 2002
  • In XXI century it is necessary to expect the recommencement and development of activities on mastering the Moon. In the long term it is construction of manned lunar bases with industrial, astrophysical, procuring, repair equipment and services. Interplanetary flights from the Moon demand smaller power expenditures, than from the Earth, therefore it is favourable to use its surface for the construction of space-vehicle launching sites. Flights of devices in libration points in the system 'Earth - Moon' are considered. Experience of engineering system creation for the Moon displays the great complexity in provision of serviceability and reliability of friction units. Open friction units should operate under following conditions on the Moon: pressure of environment (vacuum) $p\;>10\;^{-10}$ Pa; wide range of temperature change $+150^{\circ}C\;...170^{\circ}C$; high evaporability of lubricants; influence of temperature gradients and warping of constructions; sublimation of elements of constructional materials; irradiation of different physical nature; effect of micrometeorites; reduced gravitation; influence of abrasive particles of lunar ground; requirements on minimization of size and weight characteristics of a construction (high tension); undesirability (impossibility) of application of liquid and plastic lubricants; vibration, shock, acoustic loadings during start and landings to the Earth; difficulties in repair-regenerative operations in conditions of the Moon etc. Adhesive interaction of conjugated surfaces is the principal reason of possible failures of rubbed units on the Moon. In the research of the Moon automatic interplanetary stations of 'Luna' (USSR), 'Surveyer', 'Apollo' (USA) series were used. Stations executed functions of flying, landing, artificial satellites of the Moon, moon-rovers and manned spacecrafts such as 'Apollo'. The experimental- theoretical researches carried out in the sixtieth years on tribology for conditions of the Moon appeared to be rather useful to engineering of an outer space exploration and the decision of complex problems for the friction units operating in extreme conditions on the Earth. For the creation of highly loaded friction units for the long service life on the Moon it is required not only to use accumulated experience and designed technologies, but also to carry out wide scientific research.

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Case-Controlled Study of Bone Mineral Density after Herbal Medicine Intake on Women living in Hong Cheon County, Gangwondo, S. Korea (일부지역여성의 한약투여후 골밀도변화에 대한 환자-대조군 연구 - 강원도 홍천군지역을 중심으로 -)

  • Cha, Yun-Yeob;Park, Hae-Mo;Kim, Yong-Ki;Kim, Gae-Suk;Lee, Sun-Dong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.1
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    • pp.322-327
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    • 2007
  • The purpose of this study was to investigate the change of female's Bone Mineral Density after taking herbal medicine. We examined age, sex, marriage, alcohol, smoking, and job of 76 female and their life style related with Osteoporosis. Bone Mineral Density was examined after 1 month (one herbal medicine), 2 months (two herbal medicine), and 3 months (three herbal medicine) between Group I (taking pear extract) and Group II (taking herbal medicine). Bone Mineral Density of Group II after 1 month was increased, but insignificant. Bone Mineral Density was not significantly different between the Group I and Group II after 2 and 3 months. In this study, we can conclude that Bone Mineral Density was increased after 1 month of taking herbal medicine. But we had inaccurate results due to limitations of this study: period of test, accuracy of instrument, impossibility of use young antlers of the deer, and etc. More detailed study should be conducted to yield more concrete results.

An Efficient Analytical Model for Floor Vibrations in Residential Buildings with Damping layer (방진층을 설치한 주거용 건축물 바닥판의 진동해석을 위한 효율적인 해석모형)

  • Lee, Dong-Guen;Kim, Tae-Ho
    • Journal of the Earthquake Engineering Society of Korea
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    • v.10 no.5 s.51
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    • pp.49-61
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    • 2006
  • The floor impact sound insulations are installed frequently for reducing the floor impact sound into the floor slab of the residential buildings in recent years. Therefore the analytical FE model considering the insulation is needed for the sound and vibration analysis of the floor and it is necessary to use a refined finite element model fer considering the large number of modes involved dynamic responses. So it is very difficult to use FE model because of the tiresome task for constructing the FE model, taking a lot of times for analysis and the impossibility of using the proportional damping. The efficient analysis and modeling method are proposed to the dynamic analysis for the floor with damping layer in this study. The floor slabs and finished layers are modeled individually and the spring elements that mean damping layers used to connect two parts. The dynamic analysis by the $Newmark-{\beta}$ method is performed to solve the non-proportional damping problem due to the damping coefficient of insulations.

An Analysis of Pre-Service Teachers' Understanding of the real number e (예비교사들의 실수 e에 대한 이해)

  • Choi, Eunah;Lee, Hong-Youl
    • Journal of the Korean School Mathematics Society
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    • v.20 no.4
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    • pp.495-519
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    • 2017
  • The purpose of this study is to analyze the concept of the real number e and to investigate the understanding of pre-service teachers about the real number e. 28 pre-service teachers were asked to take a test based on the various ideas of the real number e and 8 pre-service teachers were interviewed. The results of this study are as follows. First, a large number of pre-service teachers couldn't recognize relation between the formal definition and the representations of the real number e. Secondly, pre-service teachers judged appropriately for the irrationality and the construction impossibility of the real number e, but they couldn't provide reasonable evidence. Lastly, pre-service teachers understood the continuous compounding context and exponential function context of the real number e, but they had a difficulty in understanding the geometric context and natural logarithm context of the real number e.

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An analysis on the Deconstructed Visage in Fashion Illustration - Based on the Deconstructed Visage of Francis Bacon's Painting - (패션 일러스트레이션에 나타난 얼굴해체 - 프란시스 베이컨 회화의 얼굴해체를 바탕으로 -)

  • Choi, Jung-Hwa;Choi, Yoo-Jin
    • Fashion & Textile Research Journal
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    • v.15 no.6
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    • pp.874-885
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    • 2013
  • This study analyzes the visage in fashion illustration based on the deconstructed visage of Francis Bacon's paintings as well as analyzes fashion illustration works since 2000. The deconstructed visages in Francis Bacon's paintings are classified as blurring, elimination, distortion and division. The expressive methods and meanings in fashion illustration (according to categorization) are as follow. Blurring shows an ambiguous visage organ by the sweeping of the brush, removal of a boundary among the visage, body and clothes, gradation of organic line like visage shapes, stretching of the a plat combined to visage and fragmentation of visage. It represents an uncertainty of the fashion theme and image interpretation, impossibility of figure by ambiguity, fantastic effect and the induction of the uncanny. Elimination shows the background color's painting of a photo-montage, overlap of a cutting of visage's part and background of a plat, elimination of the visage and the elimination of eyes, nose or lips. It represents a weakened identity, the reinforcement of anonymity, creation of a violent image, and uncanny unfamiliarity. Distortion shows a distorted visage by free drawing, and unconscious drawing line, fluid digital body, combination of an unconscious curve, and an eccentric combination of the accidental. It represents the relief of specialty about realistic existence, hypothetical immateriality and fantasy. Division shows overlapped visages with different angles, the weird combination of a plural visage and different species and a plural breakaway of direction, and the position of several organs. It represents motion by power's trace, non-territory of species, ambiguity and uncertainty and the uncanny.

A Study on the Characteristics of Hospitality through Limits of the Front Gate in Korea, China and Japan - Focused on Levinas' Ethical Theory - (한·중·일의 대문경계를 통해서 본 타자에 대한 환대 특성 연구 - 레비나스의 타자윤리적 측면을 중심으로 -)

  • An, Eun-Hi;Park, Chong-Ku
    • Korean Institute of Interior Design Journal
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    • v.26 no.4
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    • pp.84-92
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    • 2017
  • Just as the front gate is located at the meeting point between the house and the street, the Subject and the Other face each other the same way. This study examines the relationship between House(subject) and Stree (other) at the boundary of the Front Gate-Face. Pursuing the aspects of the changing Front Gate-Face accordingly to the attitude of the Subject facing the Other, this study tries to analyze the possibilities and significance of the hospitality Front Gate-Face with the ethical point of view of Levinas. As architectural instance, results of examining the Front Gate-Face of traditional houses in Korea, China and Japan are as follows. Front Gate-Face of China is characterized by self-centered introversion to interact with the external world (the other). Front Gate-Face of Japan is characterized by a humble submission to the group. Front Gate-Face of Korea shows however more flexible relationship orientations in terms of hospitality, compared to Japan or China. When looking through hospitality factors, accordingly to the above mentioned Korean hospitality characteristics, the possibilities seem not be exclusively bordered inside the conceptual category perimeter suggested by Levinas' concept of hospitality. It is almost impossible for the nowadays ever-strong privacy culture to not allow room for the architectural structure of an absolute hospitality toward others. However, this impossibility not being absolute, still yields a space for a significant possibility to explore.

The Limitations against the Use of Surrender B/L under the International Banking Practice (국제은행관습상 Surrender B/L의 한계성에 관한 연구)

  • SEO, Jung-Doo
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.69
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    • pp.201-220
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    • 2016
  • A bill of lading is a document which is signed by the carrier or his agent acknowledging that the goods have been shipped on board a named vessel bound for the destination and stating the terms on which the goods so received are to be carried. Therefore, the bill of lading is a document of title enabling the holder to obtain credit from banks before the arrival of the goods, for the transfer of the bill of lading can operate as a pledge of the goods themselves. In the other words the bill of lading creates a privity between its holder and the carrier as if the contract was made. A bill of lading, for obtaining credit from banks, must appear to indicate the carrier's name and signature, the "shipped on board" notation, the port of loading and unloading stated in the sales contract and the credit. Data in the bill of lading, when read in context with the sales contract, the credit, the bill of lading itself and international standard banking practice, need not be identical to, but must not conflict with, data in that bill of lading, any other stipulated document, the sales contract or the credit. The surrender bill of lading, stamping "surrendered" on the original bill of lading by request of the shipper, is not recognized the legal effectiveness as a document of title by the statutory law and court. The surrender bill of lading may increase the risk of impossibility of payment to the holder. Therefore, the surrender bill of lading should be used restrictively between the credible parties and suggested to avoid in the other cases.

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Ex Tunc or Ex Nunc Effects of the Rescission of Contract and the Right to Damages under Korean Law and CISG (한국민법과 CISG상 계약해제의 소급효와 손해배상청구권에 관한 연구)

  • Lee, Byung-Mun;Park, Kwang-So
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.36
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    • pp.3-26
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    • 2007
  • This article attempts to describe and analyze discussions on the matter of ex tunc effect or a ex nunc effect of rescission under Korean law in comparison with those under the CISG). In addition, it tries to scrutinize the various rules on the right to damages as an effect of rescission in a comparative way. Furthermore, it compares the various rules of Korean law with the CISG as to the right to damages and evaluates them in light of the discipline of comparative law. It maintains that the liquidation theory in Korean law is more close to the CISG in that there is no ex tunc effect in rescission and in other aspects. It also argues that the construction of the effects of rescission in accordance with the liquidation theory is more plausible when one considers Korea is one of the contracting states of the CISG. In addition, the theoretical analysis and the comparative study with the CISG shows that the insistence of ex nunc effect and its interpretation on the scope of damages extends to damages for expectation interest. It is also submitted that the position under the CISG on the assumption of ex nnuc effect, is regretted in that the restitution in value of the goods in the event of impossibility of the physical restitution is not allowed in some cases which the damage claims can not be awarded for the seller due to the application of the CISG Art. 79.

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Comparative Accuracy of Terrestrial LiDAR and Unmanned Aerial Vehicles for 3D Modeling of Cultural Properties (문화재 3차원 모델링을 위한 지상 LiDAR와 UAV 정확도 비교 연구)

  • Lee, Ho-Jin;Cho, Gi-Sung
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.179-190
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    • 2017
  • A terrestrial LiDAR survey was conducted and unmanned aerial vehicle(UAV) images were taken for target cultural properties to present the utilization measures of terrestrial LiDAR and UAV in three-dimensional modeling of cultural properties for the identification of the status and restoration of cultural properties. Then the accuracy of the point clouds generated through this process was compared, an overlap analysis of the 3D model was conducted, and a convergence model was created. According to the results, the modeling with terrestrial LiDAR is more appropriate for precise survey because 3D modeling for the detection of displacement and deformation of cultural properties requires an accuracy of mm units. And UAV model has limitation as the impossibility of detailed expression of parts with sharp unevenness such as cracks of bricks. However, it is found that the UAV model has a wide range of modeling and has the advantage of modeling of real cultural properties. Finally, the convergence model created in this study using the advantages of the terrestrial LiDAR model and the UAV model could be efficiently utilized for the basic data development of cultural properties.

A Study for International Standardization of China Arbitration System (중국중재제도의 국제표준화에 대한 연구)

  • Kim, Suk-Chul
    • Journal of Arbitration Studies
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    • v.18 no.3
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    • pp.117-138
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    • 2008
  • This study lies on building the International Standardization of China Arbitration System for improving a relationship of mutual trust and the safety trade between China and other worldwide countries, especially, South Korea as their one of the biggest trading partners through the comparative analysis of China and UNCITRAL Arbitration Law. In this analysis, the differences from China and UNCITRAL in arbitration law are like belows ; lack of arbitrator's international mind, the limitation of private property right, prohibition of Ad. hoc arbitration, arbitrator's biased nationalism, localism, and their short specialties. a deficiency of the objectiveness for arbitrator's election, a judgement rejection of claimants by using nonattendance and walkout, impossibility of prior and temporary property custody for execution of arbitration award. etc. For the improvement of the International Standardization of China Arbitration, this paper propose as follows: 1) Extension of private property right, reorganization of tax system, realization of open competition, exclusion of 'Sinocentrism', globalization of arbitration system 2) The abolition of old fashioned bureaucracy with approval for ad.hoc arbitration 3) An education for arbitrator's internationalization, specialty, and to promote legal knowledge 4) A settlement of the third country arbitrators' selection for reflecting interested party's decision by the court in a selection system of arbitration committee. 5) Institutionalization of arbitration judgment that prevent for claimant's avoidance by using a withdrawal and an intentional absent 6) A permission of the right of claimant's court custody directly before the begging of arbitration request for the prevention for destruction of evidence and property concealment 7) Grant of the arbitration tribunal's interim measures of protection for private property preservation to the third party, proof security, prevention from the loss that selling the corruptible goods 8) Improvement of arbitration's efficiency from the exclusion of the obstacles that are forgery, concealed evidence, and arbitrator's bribe taking Lastly, I hope that this study will serve to promote friendly economic relationship between China and South Korea and strive for international equilibrium through the achievement of China Arbitration's International Standardization. I will finish this paper with a firm belief that this will lead to more advanced studies.

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