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Salgınların Ulusal Güvenlikteki Bağlamında Analizi
No full textSalgınların Ulusal Güvenlikteki Bağlamında Analiz
Search for new hadronic decays of h(c) and observation of h(c) -> K+K- pi(+)pi(-)pi(0)
No full textTen hadronic final states of the h(c) decays are investigated via the process psi(3686) -> pi(0)h(c), using a data sample of (448.1 +/- 2.9) x 10(6) psi(3686) events collected with the BESIII detector. The decay channel h(c) -> K+K- pi(+)pi(-)pi(0) is observed for the first time and has a measured significance of 6.0 sigma. The corresponding branching fraction is determined to be B(h(c) -> K+K- pi(+)pi(-)pi(0)) = (3.3 +/- 0.6 +/- 0.6) x 10(-3) (where the uncertainties are statistical and systematic, respectively). Evidence for the decays h(c )-> pi(+)pi(-)pi(0)eta and h(c) ->(KSK +/-)-K-0 pi(-/+)pi(+)pi(-) is found with a significance of 3.6 sigma and 3.8 sigma, respectively. The corresponding branching fractions (and upper limits) are obtained to be B(h(c) -> pi(+)pi(-)pi(0)eta) = (7.2 +/- 1.8 +/- 1.3) x 10(-3) ( (KSK +/-)-K-0 pi(-/+)pi(+)pi(-)) = (2.8 +/- 0.9 +/- 0.5) x 10(-3) ( K+K-pi(0), K+K-eta, K+K-pi(+)pi(-)eta, 2(K+K- )pi(0), K+K-pi(0)eta, (KSK +/-)-K-0 pi(-/+), and p (p) over bar pi(0)pi(0) are determined at a confidence level of 90%
ANTREPOLARIN PERFORMANSININ ENTROPI VE TOPSIS YÖNTEMİYLE DEĞERLENDİRİLMESİ
No full textUluslararası ticaretin gelişerek ürünlerin serbest dolaşımının hızlandığı bu çağda, ülkemiz için depolama ve
stoklama faaliyeti önemli bir paya sahiptir. Özellikle firmalar dış ticarette ürünlere kolayca ulaşmak ve malların
sağlıklı depolandığından emin olmak istemektedir. Uluslararası ticarete konu olan malların ülke sınırları içerisine
girdiği andan itibaren serbest dolaşıma giriş işlemleri tamamlanıncaya kadar depolandıkları yerler bu aşamada ciddi
önem arz etmektedir. Gümrüklü alanlar olarak bilinen antrepolar, ürünlerin adım adım ithalat işlemlerinin
tamamlanarak ve vergilerin ödenerek istenildiği zaman alınabilmesi gibi birçok kolaylık sunmaktadır. Yine
antrepolar, malların ithalatı esnasında gerekli izinlerin alınması ve belgelerin temin edilmesi sürecinde firmalara
herhangi bir cezai durum oluşmadan depolama faaliyetini gerçekleştirme imkanı sunmaktadır. Firmalar, ürünlerinin
ithalat işlemlerini kendi fayda/maliyet analizleri çerçevesinde antrepolar aracılığıyla gerçekleştirdiklerinde çok
amaçlı bir karar verme problemiyle karşı karşıya kalmaktadır. Dolayısıyla firmalar için antrepo seçimi bu aşamada
büyük önem arz etmektedir. Bu nedenle bu çalışmada öncelikle antrepoların performansının değerlendirilmesinde
önemli olan ana kriterler belirlenmeye çalışılmış ve kriter ağırlıklarının hesaplanmasında Entropi yöntemine
başvurulmuştur. Çalışma sonucunda tasfiyelik eşya ve ardiye ücretinin antrepoların performansını etkileyen en
önemli kriter olduğu sonucuna ulaşılmıştır. Daha sonra çok kriterli karar verme yöntemlerinden biri olan ve sıklıkla
kullanılan Topsis yöntemi ile antrepolar sıralanmıştır
Optimization of the finned double-pipe heat exchanger using nanofluids as working fluids
No full textThe heat exchanger pipe diameter has a significant effect on the flow characteristics as well as on the initial investment, operation and overall cost. Increasing fin dimensions increases the annulus hydraulic diameters. Even though the total volume of the heat exchanger remains unchanged between the finned and bare designs, the heat duty increases with increased heat transfer area for the finned design. The fins should be designed, and the dimensions should be calculated with special attention for different flow rates and heat exchanger dimensions. In this study, number, geometry and dimensions of the fins are determined using the algorithms available in the literature. The operational condition optimization is carried out accompanied with the cost analysis. In addition, the effects of the types of working fluids and fouled and clean cases are investigated for the total heat transfer enhancement in parallel with performance, lifetime and cost issues. A detailed analysis is presented for finned and unfinned double-pipe heat exchanger models for pure engine oil and its nanofluid mixtures with Ti, TiO2, Cu, CuO, Al and Al2O3 nanoparticles, multi-wall carbon nanotubes and graphene nanosheet having a constant particle concentration in the liquid phase. The nanofluid is flowing in annulus side, whereas the seawater is flowing in the tube side. It is observed that both the pressure drop and the pumping power increase with the increasing fin number and decrease with the cleanliness factor, whereas the total tube number decreases with increasing fin number. It is found that different types of nanofluids affect the cost and optimum annulus side velocity significantly. The results are summarized in several figures that consider the increasing Reynolds number with the cleanliness factor, the heat transfer coefficient and the pressure drop, the friction factor with changing mass flow rate and the cost values with corresponding annulus side velocities. Finally, the overall characteristics of the trend lines are provided in the figures
Observation of a Resonant Structure in e(+)e(-) -> K+ K- pi(0)pi(0)
No full textA partial-wave analysis is performed for the process e(+)e(-) -> K+ K- pi(0)pi(0) at the center-of-mass energies ranging from 2.000 to 2.644 GeV. The data samples of e(+)e(-) collisions, collected by the BESIII detector at the BEPCII collider with a total integrated luminosity of 300 pb(-1), are analyzed. The total Born cross sections for the process e(+)e(-) -> K+ K- pi(0)pi(0) as well as the Born cross sections for the subprocesses e(+)e(-) -> phi pi(0)pi(0), K+(1460)K-, K-1(+)(1400)K-, K-1(+)(1270)K-, and K*(+) (892)K*(-) (892), are measured versus the center-of-mass energy. The corresponding results for e(+)e(-) -> K+ K- pi(0)pi(0) and phi pi(0)pi(0) are consistent with those of BABAR with better precision. By analyzing the cross sections for the tour subprocesses, K+(1460)K-, K-1(+)(1400)K-, K-1(+)(1270)K-, and K*(+) (892)K*(-) (892) a structure with mass M = (2126.5 +/- 16.8 +/- 12.4) MeV/c(2) and width Gamma = (106.9 +/- 32.1 +/- 28.1) NleV is observed with an overall statistical significance of 6.3 sigma, although with very limited significance in the subprocesses e(+)e(-) -> K-1(+)(1270)K-, and K*(+) (892)K*(-) (892). The resonant parameters of the observed structure suggest it can be identified with the phi(2170), thus the results provide valuable input to the internal nature of the phi(2170)
Determination of Strong-Phase Parameters in D -> K-S,L(0)pi(+)pi(-)
No full textWe report the most precise measurements to date of the strong-phase parameters between D-0 and (D) over bar (0) decays to K-S,L(0)pi(+)pi(-) using a sample of 2.93 fb(-1) of e(+) e(-) annihilation data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. Our results provide the key inputs for a binned model-independent determination of the Cabibbo-Kobayashi-Maskawa angle gamma/phi(3) with B decays. Using our results, the decay model sensitivity to the gamma/phi(3 )measurement is expected to be between 0.7 degrees and 1.2 degrees, approximately a factor of three smaller than that achievable with previous measurements, based on the studies of the simulated data. The improved precision of this work ensures that measurements of gamma/phi(3) will not be limited by knowledge of strong phases for the next decade. Furthermore, our results provide critical input for other flavor-physics investigations, including charm mixing, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes
Finite-element analysis of shear tests on masonry triplets
No full text#nofulltext#The goal of this study is to develop a computational model for analyzing triplet specimens under shear loading. In order to simulate realistically the stiffness degradation and inelastic deformability during shear failure of masonry specimens, the experimental crack pattern and the estimated strength parameters were evaluated. For verification, the material assumptions and the damage theory of the numerical model were calibrated with the observed crack behavior and experimental test results. The laboratory test results and gathered data are available for numerical analysis. The objective of these numerical analyses is to determine the force-deflection relationship for better understanding of the post-cracking behavior, shear resistance and energy dissipation capacity in the joint and the bricks of real-sized masonry walls. The numerical results were also compared with the results obtained from both preliminary and recent experimental works. By using the nonlinear finite-element method in the framework of the Ansys package program, micromodeling strategies were employed for the masonry test models. Its accuracy and reliability were validated by using these gathered test data. The study carried out would help understand the masonry behavior and identify the governing factors of the complex failure process
Study of Open-Charm Decays and Radiative Transitions of the X(3872)
No full textThe processes X(3872) -> D*(0)(D) over bar (0) + c.c., gamma J/psi, gamma psi(2S), and gamma D+D- are searched for in a 9.0 fb(-1) data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe X(3872) -> D*(0)(D) over bar (0) + c.c. and find evidence for X(3872) -> gamma J/psi with statistical significances of 7.4 sigma and 3.5 sigma, respectively. No evident signals for X(3872) -> gamma psi/(2S) and gamma D+D- are found, and the upper limit on the relative branching ratio R-gamma psi {B[X(3872) -> gamma psi(2S)]}/{B[X(3872) -> gamma J/psi]} pi(+)pi(-) J/psi are also reported for decays X(3872) -> D*(0)(D) over bar (0) c.c., gamma psi(2S), gamma J/psi, and gamma D+D-, as well as the non-D*(0)(D) over bar (0) three-body decays pi D-0(0)(D) over bar (0) and gamma D-0(D) over bar (0
An Experimental Study on Sustainability of Historical Wooden Buildings Exposed to Open Sea Streams
No full textThis research deals with the impact of the microclimate on historical wooden buildings exposed to open sea streams. The Florya Ataturk Marine Mansion in Istanbul, erected on the sea, totally defenceless to weather and sea effects, has been selected as representative case study for many other buildings located in Bosphorus line. In order to address the effect of the environment on the building exposed to open sea streams microclimatic data were collected for one year. The synergistic effect of the sea-salt aerosol and microclimatic conditions were discussed for the assessment of the impact of the marine environment on the durability of the Mansion, identifying the more vulnerable parts of the building as well as the more critical periods. The results indicate that while moisture content changes from 20.9% to 36.7% and temperature changes from 14.1 degrees C to 28.7 degrees C, thermal conductivity coefficient changes from 0.18 W.m(-1)K(-1) to 0.26 W.m(-1)K(-1), according to the facade of the building and the season as similar to previous studies