RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
        • 학술지명
          펼치기
        • 주제분류
        • 발행연도
          펼치기
        • 작성언어

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재
      • KCI등재
      • KCI등재

        Investigation of the Progressive Collapse in a Suspension Bridge Under the Explosive Load

        Salar Farahmand-Tabar,Majid Barghian,Majid Vahabzadeh 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.6

        Progressive collapse is a continuous spread of initial local failure from one member to another one, fi nally causing the collapse of the structure entirely or a disproportionately large part of it. This disproportionate collapse is due to the small initial local failure induced by unpredicted attacks, exhibiting that the structural system cannot resist the development of damage due to the insuffi cient load carrying capacity. In this study, a typical suspension bridge was modeled and analyzed under explosion load. For this purpose, diff erent scenarios were investigated. Forces and moments of the superstructure, responses and the stability of the structure under the applied loads were studied. Explosion applied on the structure depends on the amount of the load and local eff ects. Also, by removing one or several elements of structures, the force is distributed in the whole structure. For loading rate on diff erent positions of the structure, it was observed that the critical position would be under the explosion and towers adjacent. Towers adjacent and the middle of the deck were prone to the maximum infl uences where should be put more attention on and be reinforced to preserve the structure from the total and local failure.

      • KCI등재

        Aril Paleness, New Physiological Disorder in Pomegranate Fruit (Punica granatum) : Physical and Chemical Changes during Exposure of Fruit Disorder

        Saeed Mahmoodi Tabar,Ali Tehranifar,Gholam Hossein Davarynejad,Seyed Hossein Nemati,Hamid Reza Zabihi 한국원예학회 2009 Horticulture, Environment, and Biotechnology Vol.50 No.4

        Aril paleness disorder causes the quality depletion of pomegranate fruits. The objective of our work was to determine circumstance of physicochemical changes during the exposure of aril paleness disorder. Disordered fruits were monitored in the 131st days of fruit set. Disordered fruits showed a significant (P ≤ 0.05) difference from intact fruits in fruit density, juice percentage, phenolic compounds, polymeric anthocyanins, titratable acidity, and total soluble solids in the 131st days of fruit set. The fruit density, juice percent, ascorbic acid, phenolic compounds, and titratable acidity decreased 2.91, 13.52, 27.46, 21.48, and 4.22%, respectively, faster than those in intact fruits. Peel percent, dry matter of juice, acidity, total soluble solids and total sugars increased 2.59, 8.13, 3.67, 5.7, and 4.85%, respectively, faster than those in intact fruits. Monomeric anthocyanins increased (200 ㎎/100 g) up to the 159th days of fruit set in intact fruits, followed by decreased 16% up to the 173rd days of fruit set. Disordered fruits showed 70% depletion in monomeric anthocyanins up to the 173rd days of fruit set. Polymeric anthocyanins increased 14.3 and 59.3% in intact fruits and disordered fruits, 14.3 and 59.3%, respectively. Both intact and disordered fruits showed 21.9 and 23.162% increase in protein up to the 159th days of fruit set, followed by a steady state in their rate of accumulation. Physical and chemical properties in both fruits showed no significant changes during the late harvest date (the 166th and 173rd days of fruit set). Exceptions to this general pattern were total soluble solids and dry matter of disordered fruit juice in which increased significantly.

      • KCI등재

        The effect of zinc, iron and manganese content on gamma shielding properties of magnesium-based alloys produced using the powder metallurgy

        Ekici Mesut Ramazan,Tabar Emre,Hoşgör Gamze,Bulut Emrah,Atasoy Ahmet 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.9

        This study investigates the effects of Zinc (Zn), Manganese (Mn), and Iron (Fe) additions on the microstructure, corrosion behaviour, biocompatibility, mechanical, and gamma-ray shielding properties of Magnesium (Mg) alloys prepared in various compositions using powder metallurgy (PM). The microstructure and mechanical properties of these alloys were analyzed using electron microscopes (SEM and FE-SEM) and X-ray diffraction (XRD) methods. The results showed positive changes in the material’s structure when the percentage of zinc added to pure magnesium increased. It was observed that the material became ductile, and the ductile fracture increased when the zinc ratio increased. The gamma-ray shielding properties of newly produced Mg-based alloys have also been discussed since they have a high potential for use in space technologies. Radiation shielding measurements have been performed using a 3′′ × 3″ NaI(Tl) scintillation detector NaI (Tl) gamma-ray spectrometer. The gamma-ray shielding parameters such as the linear attenuation coefficients (μl), mass attenuation coefficient (μm), effective atomic number (Zeff), half-value layer (HVL), and tenth-value layer (TVL) have been determined experimentally at photon energies of 0.511 MeV (emitted from a22Na radioactive point source) and 1.173 MeV and 1.332 MeV (emitting from a60Co radioactive point source). The obtained parameters have been compared to the theoretical results of the XCOM software, and a satisfactory agreement has been found. It can be said from the results that the Mg30Zn alloy has the best shielding properties among the produced materials.

      • KCI등재

        Observation of fluid layering and reverse motion in double-walled carbon nanotubes

        K. Yaghmaei,H. Rafii-Tabar 한국물리학회 2009 Current Applied Physics Vol.9 No.6

        Most modelling-based research in the field of carbon nanotube-related nano-fluidics has been concerned with the fluid flow in single-walled carbon nanotubes (SWCNTs), showing that the dynamics of the channel affect the structure and behaviour of the fluid. We have extended this work by modelling the flow of Ar in a double-walled carbon nanotube, and have modelled the flow in both the inner shell and the outer annular region of such a nanotube. We have found that the flows in these channels are strongly correlated, such that the fluid moves in opposite directions in these two regions. This phenomenon can give rise to a circulatory motion which can be exploited in nano-fluidic devices. Fluid layering phenomenon, that is usually associated with the flow of fluids in nano-scale channels, is also observed. Furthermore, we have also found that the fluid velocity in dynamic channels is smaller than in static channels, in line with the findings reported for single-walled carbon nanotubes. Most modelling-based research in the field of carbon nanotube-related nano-fluidics has been concerned with the fluid flow in single-walled carbon nanotubes (SWCNTs), showing that the dynamics of the channel affect the structure and behaviour of the fluid. We have extended this work by modelling the flow of Ar in a double-walled carbon nanotube, and have modelled the flow in both the inner shell and the outer annular region of such a nanotube. We have found that the flows in these channels are strongly correlated, such that the fluid moves in opposite directions in these two regions. This phenomenon can give rise to a circulatory motion which can be exploited in nano-fluidic devices. Fluid layering phenomenon, that is usually associated with the flow of fluids in nano-scale channels, is also observed. Furthermore, we have also found that the fluid velocity in dynamic channels is smaller than in static channels, in line with the findings reported for single-walled carbon nanotubes.

      • KCI등재

        Foliar Application of Potassium and Boron during Pomegranate (Punica granatum) Fruit Development Can Improve Fruit Quality

        Ali Tehranifar,Saeed Mahmoodi Tabar 한국원예학회 2009 Horticulture, Environment, and Biotechnology Vol.50 No.3

        The aim of this work was to evaluate the effects of different concentrations of K and B foliar application on fruit quality parameters of pomegranate fruit (Punica granatum). To achieve this objective, in 2007 a trial was carried out in a pomegranate orchard located in Ferdows region, Iran. The plants were sprayed with three K (0, 1.5, and 3 gㆍL?¹ potassium metalosate) and three B (0, 1.5, and 3 gㆍL?¹ H3BO3) concentrations, in a complete randomized design with three replications; spraying was replicated three times during fruit development stage. Foliar application of K and B significantly increased the content of K and B in the leaf (P ≤ 0.01), and peel and juice of fruit (P ≤ 0.05). The fruits of trees fertilized at the highest K concentration had higher titratable acidity and total soluble solids than those in the other treatments. Foliar K application at 1.5 and 3 gㆍL?¹ significantly (P ≤ 0.05) increased the content of anthocyanins, phenolic compounds, and antioxidant activity of fruit juice. Application of K at 3 gㆍL?¹ alone decreased the fruit firmness significantly, while the spraying of B at 3 gㆍL?¹ increased the fruit firmness significantly. Content of ascorbic acid increased significantly with increasing of K concentrations and the highest content of ascorbic acid observed in the treatment of combination of K and B at high concentration. Foliar B application significantly (P ≤ 0.05) increased the peel percentage of fruits, while it decreased significantly (P ≤ 0.05) the juice percentage. K application at 3 gㆍL?¹ alone and with combination of B applications showed the highest significant content of total sugar content. Electrolyte leakage of fruit peel decreased significantly (P ≤ 0.05) by foliar K application compared with no K fertilizer application.

      • KCI등재후보

        Investigation of major parameters affecting instability of steel beams with RBS moment connections

        A. Deylami,A. Moslehi Tabar 국제구조공학회 2006 Steel and Composite Structures, An International J Vol.6 No.3

        One of the most promising ways through which a steel moment frame may attain high energy dissipating capability is to trim off a portion of the beam flanges near the column face. This type of moment connection, known as Reduced Beam Section (RBS) connection, has notable superiority in comparison with other moment connection types. As the result of the advantages of RBS moment connection, it has widely being used in practice. In spite of the good hysteretic behaviour, an RBS beam suffers from an undesirable drawback, which is local and lateral instability of the beam. The instability in the RBS beam reduces beam load-carrying capacity. This paper aims to investigate key issues influencing cyclic behaviour of RBS beams. To this end, a numerical analysis was conducted on a series of steel subassemblies with various geometric properties. The obtained results together with the existing experimental data are used to study the instability of RBS beams. A new slenderness concept is presented to control an RBS beam for combined local and lateral instability. This concept is in good agreement with the numerical and experimental results. Finally, a model is developed for the prediction of the magnitude of moment degradation owing to the instability of an RBS beam.

      • The Results of a Breast Cancer Screening Camp at a District Level in Rural India

        Reddy, Neha,Ninan, Tilu,Tabar, Laszlo,Bevers, Therese Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

        Background: Breast cancer in developing countries is on the rise. There are currently no guidelines to screen women at risk in India. Since mammography in the western world is a well-accepted screening tool to prevent late presentation of breast cancer and improve mortality, it is intuitive to adopt mammography as a screening tool of choice. However, it is expensive and fraught with logistical issues in developing countries like India. Materials and Methods: Our breast cancer screening camp was done at a local district hospital in India after approval from the director and administrators. After initial training of local health care workers, a one-day camp was held. Clinical breast examination, mammograms, as well as diagnostic evaluation with ultrasound and fine needle aspiration biopsy were utilized. Results: Out of total 68 women screened only 2 women with previous history of breast cancer were diagnosed with breast cancer recurrence. None of the women in other groups were diagnosed with breast cancer despite suspicious lesions either on clinical exam, mammogram or ultrasound. Most suspicious lesions were fibroadenomas. The average cost of screening women who underwent mammography, ultrasound and fine needle aspiration was $30 dollars, whereas it was $16 in women who had simple clinical breast examination. Conclusions: Local camps act as catalysts for women to seek medical attention or discuss with local health care workers concerns of discovering new lumps or developing breast symptoms. Our camp did diagnose recurrence of breast cancer in two previously treated breast cancer patients, who were promptly referred to a regional cancer hospital. Further studies are needed in countries like India to identify the best screening tool to decrease the presentation of breast cancer in advanced stages and to reduce mortality.

      • KCI등재

        REMARKS ON THE INNER POWER OF GRAPHS

        JAFARI, S.,ASHRAFI, A.R.,FATH-TABAR, G.H.,TAVAKOLI, Mostafa The Korean Society for Computational and Applied M 2017 Journal of applied mathematics & informatics Vol.35 No.1

        Let G be a graph and k is a positive integer. Hammack and Livesay in [The inner power of a graph, Ars Math. Contemp., 3 (2010), no. 2, 193-199] introduced a new graph operation $G^{(k)}$, called the $k^{th}$ inner power of G. In this paper, it is proved that if G is bipartite then $G^{(2)}$ has exactly three components such that one of them is bipartite and two others are isomorphic. As a consequence the edge frustration index of $G^{(2)}$ is computed based on the same values as for the original graph G. We also compute the first and second Zagreb indices and coindices of $G^{(2)}$.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼