3D Simulation of Ship Motions to Support the Planning of Rescue Operations on Damaged Ships

AbstractThe paper describes a software system to simulate the ship motions in a crisis situation. The scenario consists of a damaged ship subjected to wave excitation forces generated by a random sea state. The simulation is displayed in an interactive Virtual Environment allowing the visualization of the ship motions. The numerical simulation of the sea surface and ship motions requires intensive computation to maintain the real-time or even the fast-forward simulations, which are the only ones of interest for these situations. Dedicated tools to analyse the ship behaviour in time are also described. The system can be useful to evaluate the responses of the ship to the current sea state, namely the amplitude, variations and tendencies of ship motions, and help the planning and coordination of rescue operations

Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case

Dis Colon Rectum. 2006 Apr;49(4):524-6. Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case. Lopes LM, Ramada JM, Certo MG, Pereira PR, Soares JM, Ribeiro M, Areias J, Pinho C. SourceGastroenterology Department, Hospital Geral Santo António, Porto, Portugal. [email protected] Abstract Idiopathic varices of the entire colon are very rare. We report on a 64-year-old patient with massive lower gastrointestinal hemorrhage from an extensive ileocolonic varix. Diagnosis was established by colonoscopy. The patient underwent an emergency ileocolectomy with satisfactory results. This rare case shows the importance of colonoscopy in the evaluation of patients with lower gastrointestinal hemorrhage and reminds us that sometimes the diagnosis is not what we expect. Recognition of this abnormality is important because varices may be the cause of massive lower gastrointestinal hemorrhage. PMID: 16395635 [PubMed - indexed for MEDLINE

Radiative B decays to the axial KK mesons at next-to-leading order

We calculate the branching ratios of $B\to K_1\gamma$ at next-to-leading order (NLO) of $\alpha_s$ where $K_1$ is the orbitally excited axial vector meson. The NLO decay amplitude is divided into the vertex correction and the hard spectator interaction part. The one is proportional to the weak form factor of $B\to K_1$ transition while the other is a convolution between light-cone distribution amplitudes and hard scattering kernel. Using the light-cone sum rule results for the form factor, we have \calB(B^0\to K_1^0(1270)\gamma)=(0.828\pm0.335)\times 10^{-5} and \calB(B^0\to K_1^0(1400)\gamma)=(0.393\pm0.151)\times 10^{-5}.Comment: 17pages, 4 figures. Minor changes, typos corrected. PRD accepted versio

Sources of CP Violation in the Two-Higgs Doublet Model

Assuming CP violation arises solely through the Higgs potential, we develop the most general two-Higgs doublet model. There is no discrete symmetry that distinguishes the two Higgs bosons. It is assumed that an approximate global family symmetry sufficiently suppresses flavor-changing neutral scalar interactions. In addition to a CKM phase, neutral boson mixing, and superweak effects, there can be significant CP violation due to charged Higgs boson exchange. The value of $\epsilon'/\epsilon$ due to this last effect could be as large as in the standard model.Comment: 8 pages, RevTex, (appear in Phys. Rev. Lett. 73, (1994) 1762 ), CMU-HEP94-1

Nonfactorization and the decays Ds+→ϕπ+,ϕρ+D_s^+ \to \phi \pi^+, \phi \rho^+ and ϕl+νl\phi l^+ \nu_l

In six chosen scenarios for the $q^2$ dependence of the form factors involved in $D_s^+ \rightarrow \phi$ transition, we have determined the allowed domain of $x = A_2(0) / A_1(0)$ and $y = V(0)/A_1(0)$ from the experimentally measured ratios $R_{sl} = \Gamma(D_s^+ \rightarrow \phi l^+ \nu_l)/\Gamma(D_s^+ \rightarrow \phi \pi^+)$ and $R_h = \Gamma(D_s^+ \rightarrow \phi \rho^+)/\Gamma(D_s^+ \rightarrow \phi \pi^+)$ in a scheme that uses the $N_c =3$ value of the phenomenological parameter $a_1$ and includes nonfactorized contribution. We find that the experimentally measured values of $x$ and $y$ from semileptonic decays of $D_s^+$ favor solutions which have significant nonfactorized contribution, and, in particular, $R_{sl}$ favors solutions in scenarios where $A_1(q^2)$ is either flat or decreasing with $q^2$.Comment: 15 pages, Latex, four figure (available on request)

Nonfactorization and Color-Suppressed B→ψ(ψ(2S))+K(K∗)B \to \psi (\psi(2S))+K(K^*) Decays

Using $N_c=3$ value of the parameter $a_2=0.09$ but including a modest nonfactorized amplitude, we show that it is possible to understand all data, including polarization, for color-suppressed $B\to\psi(\psi(2S))+K(K^*)$ decays in all commonly used models of form factors. We show that for $B\to\psi +K$ decay one can define an effective $a_2$, which is process-dependent and, in general, complex; but it is not possible to define an effective $a_2$ for $B\to\psi +K^*$ decay. We also explain why nonfactorized amplitudes do not play a significant role in color-favored B decays.Comment: 13 pages, Latex, one figure (not included

Form factors of heavy-to-light B decays at large recoil

General relations between the form factors of B decays to light mesons are derived using the heavy quark and large recoil expansion. On their basis the complete account of contributions of second order in the ratio of the light meson mass to the large recoil energy is performed. Both ground and excited final meson states are considered. It is shown that most of the known form factor relations remain valid after the inclusion of quadratic mass corrections. The validity of some of such relations requires additional equalities for the helicity amplitudes. It is found that all these relations and equalities are fulfilled in the relativistic quark model based on the quasipotential approach in quantum field theory. The contribution of 1/m_b corrections to the branching fraction of the rare radiative B decay is discussed.Comment: 23 pages, revte

Virtual O(\a_s) corrections to the inclusive decay b→sγb \to s \gamma

We present in detail the calculation of the O(\a_s) virtual corrections to the matrix element for b \to s \g. Besides the one-loop virtual corrections of the electromagnetic and color dipole operators $O_7$ and $O_8$, we include the important two-loop contribution of the four-Fermi operator $O_2$. By applying the Mellin-Barnes representation to certain internal propagators, the result of the two-loop diagrams is obtained analytically as an expansion in $m_c/m_b$. These results are then combined with existing O(\a_s) Bremsstrahlung corrections in order to obtain the inclusive rate for B \to X_s \g. The new contributions drastically reduce the large renormalization scale dependence of the leading logarithmic result. Thus a very precise Standard Model prediction for this inclusive process will become possible once also the corrections to the Wilson coefficients are available.Comment: 29 pages, uses epsfig.sty, 12 postscript figures include