• 제목/요약/키워드: flowing well

검색결과 237건 처리시간 0.025초

액체소듐 환경에서 Ferritic-Martensitic강의 미세조직 및 기계적 성질 평가 (Microstructural and Mechanical Property Evaluation of the Ferritic-Martensitic Steel under Liquid Sodium Environment)

  • 김준환;김종만;김성호;이찬복
    • 대한금속재료학회지
    • /
    • 제48권10호
    • /
    • pp.914-921
    • /
    • 2010
  • Studies were carried out to assess the microstructural and mechanical properties of ferriticmartensitic steel under a flowing sodium environment. HT9 (12Cr-MoVW) and Gr.92 (9Cr-MoVNbW) steel were exposed to liquid sodium at $650^{\circ}C$ containing dissolved oxygen of 20 ppm for 2333 hours and evaluations of the microstructure as well as the mechanical properties of the microhardness and nanoindentation were carried out. The result showed that both HT9 and Gr.92 exhibited macroscopic weight loss caused by general corrosion as well as localized types such as intergranular corrosion and pitting. Decarburization at the steel surface took place as the test proceeded. As the Cr content increased, dissolution and decarburization were suppressed. Assessment of the actual cladding geometry revealed that an aging process rather than decarburization governed the mechanical properties, which resulted in a decrease of the microhardness and yield stress.

Spiral Magnetic Field Lines in a Hub-Filament Structure, Monoceros R2

  • Hwang, Jihye;Kim, Jongsoo
    • 천문학회보
    • /
    • 제45권1호
    • /
    • pp.59.3-60
    • /
    • 2020
  • We present the results of polarization observations at submillimeter wavelengths towards Monoceros R2 (Mon R2). The polarized thermal dust emission was obtained from SCUBA-2/POL-2 at 450 ㎛ and 850 ㎛, simultaneously. This observation is a part of the JCMT BISTRO survey project. The polarization angle distributions at 450 ㎛ and 850 ㎛ are similar and the mean value of angle differences at two wavelengths is 5.5 degrees. The Mon R2 is one of massive star-forming regions containing a clear hub-filamentary structure. The hub region shows star formation activities, and surrounding filaments provide channels for matters to move into the hub region. It is not well known the role of magnetic fields in a hub-filamentary structure. Some studies have shown well-ordered polarization segments along a filamentary structure and magnetic field morphology traced by polarization segments is interpreted as to help gas flow along the filamentary structrue. Our observations shows that filaments in Mon R2 have spiral structure and the magnetic field lines are parallel to the filaments. We interpret that the spiral structure can be formed by a rotation hub-filament system with gas flowing along the filaments to the hub. We found several dust clumps at the central part of the hub region of the Mon R2. They seems to be formed at locations where spiral field lines meet each other. These results show one observational example that a magnetic field play a role in gas flow.

  • PDF

구체혼화용 분말방수재의 적용성에 관한 실험적 연구 (An Experimental Study on Application of Waterproofing admixture of Powder)

  • 강희권;송제영;오상근
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2004년도 학술.기술논문발표회
    • /
    • pp.65-70
    • /
    • 2004
  • The purpose of this study is to offer the basic information of waterproofing admixture of powder for field application. Through before study and fly ash in mortar, Various properties as fly ash ratio in concrete were checked. According to the experimental result, it was shown that proper Waterproofing admixture of powder increased by cement weight in concrete was generally positive effort to flowing, compressive strength, suction ratio of water, length of ratio. So if Waterproofing admixture of powder il well done quality considered as good in application of concrete.

  • PDF

물류비 절감을 통한 기업경쟁력 강화방안 (The Study on Improvement of the Logistics Competition in Korea Enterprise)

  • 양화섭
    • 경영과정보연구
    • /
    • 제16권
    • /
    • pp.77-94
    • /
    • 2005
  • Nowadays, to change our country into advanced economy, the factor of growth obstacles was to be eliminated, or it is so important that the logistics base establishment enlarges to improve potential productivity. The best strategy to enforce the competition power is that we should be ready for some condition which can do cooperations and association very well. Also it is necessary for actors, government, firm and logistics field, to part their role. The national effort that firm supported by government and community participates in is reduced to achieve rational logistics system because logistics is complicate action flowing to final consumer. That is, self effort is needed for logistics competition system, adjustable arrangement of logistics field, the establishment of comprehensive informations system, logistics rationalization.

  • PDF

복잡한다 층구조 IC 패키지의 회로 모델링 및 스위칭 노이즈 분석 (A Simplified Circuit Model and Switching Noise Characterization of the Complicated Multi-Layer IC Package)

  • 유한종;어영선
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 추계종합학술대회 논문집
    • /
    • pp.1049-1052
    • /
    • 1998
  • A new simplified circuit model for the switching noise analysis of the complicated multi-layer IC package is developed. The current flowing mechanism on the ground and power planes of the package is simplified by using the dependent current soures and partial plane circuit model. The methodology is very cost-efficient as well as accurate. It is demonstrated that the nosie based on the simplified circuit model has an excellent agreement with that of the complicated full circuit model. However, the simplified model takes only 5 minutes for the switching noise simulation, while the full circuit model takes more than 4 hours.

  • PDF

라이닝콘크리트에서의 FA적용에 관한 실험적 연구 (An Experimental Study on the Application of Fly Ash for Lining Concrete)

  • 최세진;임정열;김완영;김무한
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
    • /
    • pp.151-154
    • /
    • 1999
  • The lining concrete of water tunnel is a structure that is constructed to prevent from corroding of the rock around tunnel and reduce the deterioration of geology by flowing water, and to improve the durability of tunnel, which must not only economy, stability but also satisfy the engeneering properties of concrete. This is an experimental study to analyze th usability of fly in the tunnel lining concrete. For this purpose, after select the mix proportion of plain concrete and concrete using fly ash(the replacement of 15 and 30% by weight of cement) to satisfy slump, air content and compressive strength through the mix design, the test of slump, setting time, compressive strength, tensile strength, drying shrinkage and adiabatic temperature rise was performed. According to test results, it was found that FA 15 concrete was more effective than the others to reduce drying shrinkage as well satisfy other engineering properties.

  • PDF

의정부시 주택 현황에 관한 연구 (A Study on The Present State of Housing in Uijeongbu City)

  • 김종환
    • 한국디지털건축인테리어학회논문집
    • /
    • 제4권2호
    • /
    • pp.19-25
    • /
    • 2004
  • This study is to furnish basic data for establishing the improvement counterplan of Housing environment and to solve the problem of Housing supply resulting from the continuous increase of population and to examine the historical flowing, the present condition and problems of Housing in Uijeongbu city. Including of the multi-house to the number of Housing, the supply ratio of Housing is 95% in quantity of the Housing in Uijeongbu city in 2004. Now, it is important time in the respect of quality as well as the quantity in supply matter of Housing. In fact, the main viewpoint in housing supply policy has been brought focus into the economic profits more than public interests. As a result of that, the residence environment has been worse. From now on, a Local autonomous entity including the construction authorities and Uijeongbu city authorities must focus on the public interests in solving problems of Housing.

  • PDF

The Change of Water Quality In Osaka Bay during Recent 70 Years

  • Han, Dong-Jin;Yoon, Jong-Sung
    • 한국환경과학회지
    • /
    • 제13권11호
    • /
    • pp.1001-1007
    • /
    • 2004
  • The rapid industrialization and urbanization in Osaka Bay have produced many serious water pollution problems since the 1960s. A symbolic phenomenon is algae bloom (red tide), which occurred 53 times in 1976. The special law was enacted in 1973 and a number of administrative steps were taken, such as cutting COD loading, reductions in phosphorus (P) and restriction of land reclamation. As a result, the pollution of Osaka Bay has gradually been reduced, and the environment has been improved to some extent. In this study, to analyze the relations between water qualities as well as a social, economic activity by the coastal zone, the water quality data in Osaka Bay of 70 years past since 1921 were collected. Data such as population, livestock, fertilizer, industrial product etc. were also collected for estimating nutrients flowing into bay from land. It was found that the water quality was changed of a similar trend of estimated nutrients load, with delay of about four or five years.

방제(方劑)에서 행인(杏仁)의 역할에 관한 문헌적 고찰 (The Role of Armeniacae Amarum Semen in Herbal Formula)

  • 변성희;김한균;지선영;이병욱;김상찬
    • 대한한의학방제학회지
    • /
    • 제11권2호
    • /
    • pp.29-40
    • /
    • 2003
  • Armeniacae Amarum Semen was well-known as a theraputic agent of asthma by flowing downward of qi and moistening of lung in Oriental Medicine. But there are many other effect in Armeniacae Amarum Semen such as, loosening the bowel to relieve constipation, removing stagnation of qi and food, dispersing accumulation of pathogen, parasiticide. We have been studying what the meaning of Armeniacae Amarum Semen in herbal formula and usage of Armeniacae Amarum Semen is.

  • PDF

액티브 네트워크 응용의 검증 (Verifying Active Network Applications)

  • 박준철
    • 한국정보과학회논문지:정보통신
    • /
    • 제29권5호
    • /
    • pp.510-523
    • /
    • 2002
  • The routers in an active network perform customized computations on the messages flowing through them, while the role of routers in the traditional packet network, such as the Internet, is to passively forward packets as fast as possible. In contrast to the Internet, the processing in active networks can be customized on a per user or per application basis. Active networks allow users to inject information into the network, where the information describes or controls a program to be executed for the users by the routers as well as the end hosts. So the network users can realize the active networks by "programming" the network behavior via the programming interface exposed to them. In this paper, we devise a network protocol model and present a verification technique for reasoning about the correctness of an active application defined using the model. The technique is developed in a platform- and language-independent way, and it is algorithmic and can be automated by computer program. We give an example dealing with network auction to illustrate the use of the model and the verification technique.