Fire resistance performance of submerged floating tunnel under various fire conditions

Submerged Floating Tunnels (SFT) were researched by countries had many island as Norway, Italy,\ud China, and Japan. Several sites were examined in China and Norway. Most of them investigated about seismic, dynamic,\ud and collision performance. However, present researches lack to apply the construction fields, therefore, additional\ud researches need. Fire resistance performance of the SFT is important one of the various researches. If fire break out in\ud SFT, it is damaged by thermal loads. The damage of the SFT varies by type of fire. Structure of the SFT is able to\ud collapse partially by fire scale and fire exposure time. For this reason, fire resistance design of the SFT must be\ud suggested. Fire resistance performance of SFT could be investigating for fire resistance design of SFT. Fire condition\ud could be expressed fire curves which are suggested by fire scale and fire exposure time. In this paper, temperature\ud distributions of the SFT were investigated through FE analysis under various fire conditions. Heat transfer analysis was\ud applied to investigate conduction of heat by fire. And there was to draw the biggest influence fire condition to the SFT\ud from FE analysis results. Also, preliminary study was performed for fire resistance design

Transient response analysis of a submerged floating tunnel under seismic and wave excitations

In this study, a numerical procedure is described for the transient response analysis of a submerged\ud floating tunnel with reference of a designed tunnel in Japan. Tension legs seizing the tunnel are simply modeled by a\ud spring elements and the tunnel itself is assumed by two rigid bodies between which a flexible joint is used. A recorded\ud seismic excitation is used while the wave load is calculated under a specific design condition. Hydro-damping and\ud added mass are considered for numerically modeling the underwater condition. A numerical procedure is validated with\ud compared to the previous results of the designed tunnel. Some modifications are proposed through the validating\ud process in terms of modeling and analysis procedure. Eventually, the modified numerical procedure will be used in\ud analyzing the transient response of a newly designed tunnel

Design and fabrication of double pancake coil using 2G wire for conduction cooled superconducting magnet

AbstractA large bore double pancake coil(DPC) was designed and tested with 2G HTS wire to develop the conduction cooled superconducting magnet with central field intensity of 3 T at 20K operating temperature and clear bore of 100mm at room temperature. The effect of insulation between turns of double pancake coils was tested. Two double pancake coils with and without turn to turn insulation were wound using 4mm wide 2G conductor. A temporary result suggests that the coil wound without electrical insulation can be protected from higher over current and shows improved stability

Bending strength analysis of steel-composite submerged floating tunnels

A submerged floating tunnel (SFT) must have enough strength to resist to various external loadings such\ud as bending, torsion, tension, and compression. The expected main deformation of SFT is caused by bending moment.\ud And this bending moment makes tensile stress and compression stress on the wall of SFT. Thus, bending moment is a\ud main affecting factor on the safety of SFT. Until now, a reinforced concrete tunnel was suggested for SFT by other\ud researchers. In this study, an internally confined hollow reinforced concrete tunnel and a double skinned composite\ud tubular tunnel were proposed. And their bending strengths were studied and compared with that of a reinforced concrete\ud tunnel. The analysis results showed the proposed SFT structures had enough strength to guarantee safety

Observations sur les relations trophiques entre les bruches du genre Caryedon (Coléoptères, Bruchidae) et leurs plantes hôtes sauvages au Sénégal

Treize espèces de bruches du genre #Caryedon ont été recensées dans des graines de diverses Césalpiniacées, Mimosacées et Combrétacées provenant de la partie occidentale du Sénégal. En se fondant également sur des données bibliographiques, les auteurs constatent que onze des espèces sénégalaises de #Caryedon sont monophages, car leurs plantes hôtes appartiennent à un seul genre. Seuls #C. serratus et #C. crampeli sont oligophages, et utilisent des plantes hôtes appartenant à plus d'un genre. #C. serratus s'est adapté à l'arachide, qui est une Fabacée introduite. En revanche, aucune espèce de #Caryedon ne parasite les Fabacées sauvages. (Résumé d'auteur

Alteration patterns of trabecular bone microarchitectural characteristics induced by osteoarthritis over time

10.2147/CIA.S32513Clinical Interventions in Aging7303-31

Low-Frequency Optical Conductivity in Inhomogeneous d-wave Superconductors

Motivated by the recent optical conductivity experiments on Bi_2Sr_2CaCu_2O_{8+delta} films, we examine the possible origin of low-frequency dissipation in the superconducting state. In the presence of spatial inhomogeneity of the local phase stiffness rho_s, it is shown that some spectral weight is removed from omega=0 to finite frequencies and contribute to dissipation. A case where both rho_s and the local normal fluid density are inhomogeneous is also considered. We find an enhanced dissipation at low frequency if the two variations are anti-correlated.Comment: To appear in Phys. Rev.

Estimating Carbon Dynamics in an Intact Lowland Mixed Dipterocarp Forest Using a Forest Carbon Model

Intact dipterocarp forests in Asia act as crucial carbon (C) reservoirs, and it is therefore important to investigate the C dynamics in these forests. We estimated C dynamics, together with net ecosystem production (NEP), in an intact tropical dipterocarp forest of Brunei Darussalam. Fifty-four simulation units (plots; 20 m × 20 m) were established and initial C stocks were determined via direct field measurement. The C dynamics were annually simulated with a regression model and the Forest Biomass and Dead organic matter Carbon (FBDC) model. The initial C stock (Mg C·ha−1) of biomass, litter, dead wood and mineral soil were 213.1 ± 104.8, 2.0 ± 0.8, 31.3 ± 38.8, and 80.7 ± 15.5, respectively. Their annual changes (Mg C·ha−1·year−1) were 3.2 ± 1.1, 0.2 ± 0.2, −3.7 ± 6.1, and −0.3 ± 1.1, respectively. NEP was −0.6 ± 6.1 Mg C·ha−1·year−1, showing large heterogeneity among the plots. The initial C stocks of biomass and dead wood, biomass turnover rates and dead wood decay rates were elucidated as dominant factors determining NEP in a sensitivity analysis. Accordingly, investigation on those input data can constrain an uncertainty in determining NEP in the intact tropical forests

Path finding strategies in scale-free networks

We numerically investigate the scale-free network model of Barab{\'a}si and Albert [A. L. Barab{\'a}si and R. Albert, Science {\bf 286}, 509 (1999)] through the use of various path finding strategies. In real networks, global network information is not accessible to each vertex, and the actual path connecting two vertices can sometimes be much longer than the shortest one. A generalized diameter depending on the actual path finding strategy is introduced, and a simple strategy, which utilizes only local information on the connectivity, is suggested and shown to yield small-world behavior: the diameter $D$ of the network increases logarithmically with the network size $N$, the same as is found with global strategy. If paths are sought at random, $D \sim N^{0.5}$ is found.Comment: 4 pages, final for

Impurity state in the vortex core of d-wave superconductors: Anderson impurity model versus unitary impurity model

Using an extended Anderson/Kondo impurity model to describe the magnetic moments around an impurity doped in high-$T_{\text{c}}$ d-wave cuprates and in the framework of the slave-boson meanfield approach, we study numerically the impurity state in the vortex core by exact diagonalization of the well-established Bogoliubov-de Gennes equations. The low-energy impurity state is found to be good agreement with scanning tunnelingmicroscopy observation. After pinning a vortex on the impurity site, we compare the unitary impurity model with the extended Anderson impurity model by examining the effect of the magnetic field on the impurity state. We find that the impurity resonance in the unitary impurity model is strongly suppressed by the vortex; while it is insensitive to the field in the extended Anderson impurity model.Comment: 8 pages, 3 figure