(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).Prompt D meson and non-prompt J/ psi yields are studied as a function of the multiplicity of charged particles produced in ...inelastic proton-proton collisions at a centre-of-mass energy of ... TeV. The results are reported as a ratio between yields in a given multiplicity interval normalised to the multiplicity-integrated ones (relative yields). They are shown as a function of the multiplicity of charged particles normalised to the average value for inelastic collisions (relative charged-particle multiplicity). D super(0), D super(+) and D super(*+) mesons are measured in five p sub(T) intervals from 1 GeV/c to 20 GeV/c and for |y| < 0.5 via their hadronic decays. The D-meson relative yield is found to increase with increasing charged-particle multiplicity. For events with multiplicity six times higher than the average multiplicity of inelastic collisions, a yield enhancement of a factor about 15 relative to the multiplicity-integrated yield in inelastic collisions is observed. The yield enhancement is independent of transverse momentum within the uncertainties of the measurement. The D super(0)-meson relative yield is also measured as a function of the relative multiplicity at forward pseudo-rapidity. The non-prompt J/ psi , i.e. the B hadron, contribution to the inclusive J/ psi production is measured in the di-electron decay channel at central rapidity. It is evaluated for p sub(T) > 1.3 GeV/c and |y| < 0.9, and extrapolated to p sub(T) > 0. The fraction of non-prompt J/ psi in the inclusive J/ psi yields shows no dependence on the charged-particle multiplicity at central rapidity. Charm and beauty hadron relative yields exhibit a similar increase with increasing charged-particle multiplicity. The measurements are compared to PYTHIA 8, EPOS 3 and percolation calculations. Figure not available: see fulltext.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).The transverse momentum (p sub(T)) dependence of the nuclear modification factor R sub(AA) and the centrality dependence of ...the average transverse momentum p sub(T) for inclusive J/ psi have been measured with ALICE for Pb-Pb collisions at ... TeV in the e+e super(-) decay channel at mid-rapidity (|y| < 0.8). The p sub(T) is significantly smaller than the one observed for pp collisions at the same centre-of-mass energy. Consistently, an increase of R sub(AA) is observed towards low p sub(T). These observations might be indicative of a sizable contribution of charm quark coalescence to the J/ psi production. Additionally, the fraction of non-prompt J/ psi from beauty hadron decays, f sub(B), has been determined in the region 1.5 < p sub(T) < 10 GeV/c in three centrality intervals. No significant centrality dependence of f sub(B) is observed. Finally, the R sub(AA) of non-prompt J/ psi is discussed and compared with model predictions. The nuclear modification in the region 4.5 < p sub(T) < 10 GeV/c is found to be stronger than predicted by most models. Figure not available: see fulltext.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).We have studied the transverse-momentum (p sub(T)) dependence of the inclusive J/ psi production in p-Pb collisions at ... ...= 5.02 TeV, in three center-of-mass rapidity (y sub(cms)) regions, down to zero p sub(T). Results in the forward and backward rapidity ranges (2.03 < y sub(cms) < 3.53 and -4.46 < y sub(cms) < -2.96) are obtained by studying the J/ psi decay to mu super( )+ mu super( )- while the mid-rapidity region (-1.37 < y sub(cms) < 0.43) is investigated by measuring the e super(+)e super(-) decay channel. The p sub(T) dependence of the J/ psi production cross section and nuclear modification factor are presented for each of the rapidity intervals, as well as the J/ psi mean p sub(T) values. Forward and mid-rapidity results show a suppression of the J/ psi yield, with respect to pp collisions, which decreases with increasing p sub(T). At backward rapidity no significant J/ psi suppression is observed. Theoretical models including a combination of cold nuclear matter effects such as shadowing and partonic energy loss, are in fair agreement with the data, except at forward rapidity and low transverse momentum. The implications of the p-Pb results for the evaluation of cold nuclear matter effects on J/ psi production in Pb-Pb collisions are also discussed. Figure not available: see fulltext.
New technologies for ships affect many aspects of seafarers' lives at work. Nowadays, many shipowners provide their ships with internet access for the personal use of the crew. After all these ...developments, nomophobia is no longer a phenomenon far from seafarers. Nomophobia affects mental health and motivation in seafarers, like all people who can use smartphones. Until now, there has been no study investigating nomophobia in seafarers and its effects on life at sea.
This study aimed to determine the prevalence of nomophobia among seafarers and examine the causes and consequences of differences between groups.
A previously designed and tested questionnaire was used to determine nomophobia and its effects on seafarers. Three hundred fifty one seafarers participated in the study. ANOVA and T-tests were performed with SPSS 22 package program to find significant differences.
Nomophobia differed significantly according to age groups, gender, and education level. Headache and fatigue increased in direct proportion to the level of nomophobia.
It was found that 65.2% of the seafarers had moderate to severe nomophobia.
The point load (PL) test is generally used for estimation of uniaxial compressive strength (UCS) of rocks because of its economic advantages and simplicity in testing. If the PL index of a specimen ...is known, the UCS can be estimated using conversion factors. Several conversion factors have been proposed by various researchers and they are dependent upon the rock type. In the literature, conversion factors on different sedimentary, igneous and metamorphic rocks can be found, but no study exists on trona. In this study, laboratory UCS and field PL tests were carried out on trona and interbeds of volcano-sedimentary rocks. Based on these tests, PL to UCS conversion factors of trona and interbeds are proposed. The tests were modeled numerically using a distinct element method (DEM) software, particle flow code (PFC), in an attempt to guide researchers having various types of modeling problems (excavation, cavern design, hydraulic fracturing, etc.) of the abovementioned rock types. Average PFC parallel bond contact model micro properties for the trona and interbeds were determined within this study so that future researchers can use them to avoid the rigorous PFC calibration procedure. It was observed that PFC overestimates the tensile strength of the rocks by a factor that ranges from 22 to 106.
•The UCS to IS50 linear conversion factor for the trona and interbeds is 14.24 and 25.96, respectively.•Multiple trial and error iterations were completed until reproducing the test behavior of UCS and point load tests.•Average PFC parallel bond contact model micro properties for the trona and interbeds were determined.•It was observed that PFC overestimates the tensile strength of the rocks by a factor that ranges from 22 to 106.
Given the needs of the growing world population, the importance of the transportation sector has steadily increased. Maritime and aviation fields are considered two crucial parts of this sector. ...Transportation accidents must be minimized in order to ensure timely delivery of natural resources, sustainable production and safety of life and property. Human error plays an important role in transportation accidents and is the cause of 70-90% of all aviation and maritime accidents. These errors can be minimized by enhancing the perception of safety culture for individuals, corporations and nations. In this study, a questionnaire survey was conducted among 318 Turkish people who work in different positions in the aviation and maritime industries. The perceptions of safety culture within different occupations and occupational groups were compared. Statistically significant differences were found between the aviation and maritime sectors.
Maritime transportation is indispensable for world trade. Marine casualties have serious consequences. The majority of the accidents in the maritime industry are caused by human error. If necessary ...precautions are taken, human error can be prevented to a great extent. Safety culture is of tremendous importance in taking precautions and preventing accidents. The concept of safety culture emerged after the Chernobyl accident. Today, the importance of safety culture in preventing accidents is accepted by all international organizations. There are many elements affecting safety culture. In this study, the situation of the safety culture of 221 deck officers against many variables was examined. According to the analysis of variance test, it has been observed that the vessel type has a significant effect on safety culture even among the officers who graduated from the same college.
Recently, miniaturization of Raman, mid-infrared (IR), and near-infrared (NIR) spectrometers has made substantial progress. Though mid-infrared systems are based exclusively on attenuated total ...reflection (ATR) measurements, near-infrared spectrometers operate in the diffuse reflection or transmission mode. The reduction in size, however, must not be accompanied by deterioration in measurement performance, and portable instrumentation will only have a real impact on quality and process control if Raman, IR, and NIR spectra of comparable quality to laboratory spectrometers can be obtained.
In the present communication, a short overview on the building principles of novel handheld systems will be provided and the results of qualitative and quantitative analyses of selected liquid and solid sample systems obtained with these Raman, Fourier transform infrared (FTIR), and NIR spectrometers will be evaluated in terms of their comparability with laboratory instruments and their suitability for on-site and field measurements.
PDF
