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The goal of this work was to investigate effect of heating time during welding on mechanical properties of High Performance Polyamide thermoplastic composite material PPAGF40. Studies showed that welded joints with shorter heating time from 6.1 s to 6.7 s had a higher amount of pores and burn mark defects compared to the welded joints with longer heating time. Cross-section analysis of welded samples revealed tendency, that samples with higher heating time from 7.4 s to 11.5 s possessed more homogenous weld seam and higher resistance to burst pressure, respectively from 5.1 bar to 7.5 bar, while the resistance to pressure values of shortest heating time range, respectively are varying from 3.3 bar to 3.9 bar. The weld seam defects like pores and burn marks weakened the welded joint. 470 W of laser power energy input influenced fast melt-down of a cover and a housing, which caused material partial evaporation and later on formation of pores inside weld seam. By using lower 450 W of laser power and scanning speed of 1900 – 1700 mm/s, we can observe more homogenous weld seam. The cross-section of the samples were examined by using optical microscope. Mechanical resistance to pressure was performed in order to evaluate the performance of welded joints of different heating time of PPAGF40.

We assessed the prevalence of SARS-CoV-2 in the staff of a general hospital in North-Rhine-Westphalia in a cross-sectional study.Employees (n = 1363) were offered a nasopharyngeal swab and serology for SARS-CoV-2. Additionally, employees completed a questionnaire about preexisting conditions, contacts with SARS-CoV-2-positive individuals and COVID-19-specific symptoms.1212 employees participated. 19 of 1363 (1.4 %) employees tested positive by PCR (3 within and 16 before the study). 40 (3.3 %) and 105 (8.6 %) had IgG and IgA, respectively, 32 (2.6 %) both IgG and IgA. Overall, 47 employees tested positive. In this group, most frequently reported symptoms were headache (56 %), fatigue (49 %), sore throat (49 %), and cough (46 %); fever was reported by 33 %. SARS-CoV-2-positive employees reported more frequently contact with COVID-19 cases (60.5 % vs. 37.3 %, p = 0.006). Employees testing positive only for IgA reported less symptoms.Between 27.04. and 20.05.2020, 3.9 % of the employees working in a general hospital were tested positive for SARS-CoV-2. This proportion was lower than expected; possible explanations are the low level of endemic infection and the extensive, uniform in-house preventative measures.Wir erhoben die Prävalenz von SARS-CoV-2 in der Belegschaft eines Krankenhauses der Regel-/Schwerpunktversorgung in Nordrhein-Westfalen im Rahmen einer Querschnittsstudie.Allen 1363 Mitarbeiter wurden ein nasopharyngealer Abstrich sowie eine Serologie auf SARS-CoV-2 angeboten. Zudem wurde ein Fragebogen zu Vorerkrankungen, Kontakten zu SARS-CoV-2-positiven Personen und COVID-19-typischen Symptomen vorgelegt.1212 MitarbeiterInnen nahmen teil. 19 von 1363 (1,4 %) Mitarbeitern waren PCR-positiv (3 während der Studie, 16 vorher). Bei 40 (3,3 %) bzw. 105 (8,6 %) Mitarbeitern wurde IgG bzw. IgA nachgewiesen, bei 32 (2,6 %) IgG und IgA. Damit wurden insgesamt 47 Mitarbeiter positiv für SARS-CoV-2 getestet. In dieser Gruppe waren die häufigsten Symptome Kopfschmerzen (56 %), Müdigkeit (49 %), Halsschmerzen (49 %) und Husten (46 %), Fieber wurde in 33 % berichtet. Positiv getestete Mitarbeiter gaben häufiger Kontakt zu einem COVID-19-Fall an (60,5 % vs. 37,3 %; p = 0,006). Mitarbeiter mit isoliertem IgA-Nachweis gaben seltener Symptome an.3,9 % der Mitarbeiter eines Krankenhauses der Regel-/Schwerpunktversorgung wurden zwischen dem 27.04. und 20.05.2020 positiv auf SARS-CoV-2 getestet. Der Anteil war geringer als erwartet; mögliche Gründe sind die geringe Durchseuchung der Bevölkerung und die umfangreichen, einheitlichen hausinternen Präventionsmaßnahmen.

We investigate external and domestic political influences on defence burden of the 28 EU member states, based on time-series cross-section data from 1993 to 2017. Our research is one of the most co...

Production cross sections of 225 , 226 , 228 Ac and 226 , 231 Th by the proton bombardment on 232 Th target at the proton energies from 10 MeV to 155 MeV are calculated with collective semi-classical nuclear level density model (CSCFGM) by using TALYS computer code. Collective nuclear level density effect on these reactions are investigated. The importance of collective effects (rotational and vibrational) on proton induced reactions are represented. Theoretical results are compared with the experimental data taken from EXFOR library, which shows a good agreement.

The cross-section response of smart beams under electric, magnetic and thermal fields is investigated. The method predicts the generalized cross-section stiffness of prismatic smart beams, and allo...

In this paper, we find that the relationship between the value-at-risk (VaR) and expected returns is negative and this negative relationship between the VaR and expected returns can be explained by volatility in the U.S. market. However, for different levels of investor sentiment, this relationship changes. For a high sentiment period, VaR is negatively related with the expected return and cannot be explained by momentum, short-term reversal, volatility, and financial distress. In comparison, the relation between the VaR and expected returns during a low sentiment period is mixed.

This research paper presents the Knowledge Management practice in Nepalese telecom sector. This study is based on cross section analysis of 85 observations for analyzing relationship between the knowledge management (KM) practices status in Nepalese telecom sector. The methodology used by Kohli (1993) and Daroch (2003) has been used for the research. Survey instruments we reorganized into one part and five factors. Spearman Rank Correlation, Analysis of variance (ANOVA), Cranach’s alpha etc. is used for data analysis. The valid response rate of 70 % was found. Among the factors that designed for knowledge acquisition, information input- employee has less mean score and information input-financial has high mean score than the others factors. In case of Information input-competitors, Nepalese telecom industry analyzes the financial contribution of their products or services. Employees of Nepal telecom has rated higher mean value in the KM practices i.e. knowledge acquisition, which means Nepal telecom appeared good in KM practices than Ncell. There is a significant difference between Nepal telecom and Ncell in term of the knowledge acquisition. Nepal telecom has better KA (Knowledge Acquisition) practices. Correlation matrix was computed to assess the extent or degree of relationship in between the factors or the research variables.

This article introduces EXSAN, a new open-sourced code developed for streamlined visualization and analysis of Evaluated Nuclear Data File (ENDF)-formatted nuclear data libraries. In addition to viewing cross section data, EXSAN provides the user with an intuitive interface for automated downloading of ENDF data libraries and processing entire libraries with the nuclear cross section code NJOY. Furthermore, EXSAN includes the capability to query a library and obtain rank-ordered lists of reaction-specific cross sections by cross section value and isotope. EXSAN was developed in Python, and it is available on GitHub.

We construct a new lottery measure (ALM) to evaluate the lottery preference feature of stocks. The new measure is different from the common used lottery proxies: maximum daily return (MAX) and skewness (SKEW). In the U.S. stock market, the relationship between the ALM and expected returns is negative and it can be explained by MAX. Additionally, the negative predictability of ALM is significant and cannot be explained by other controls when the investor sentiment is high. While no significant relationship has been detected between the ALM and the stock returns during the periods of low investor sentiment.

In this paper, we find a negative cross-sectional relationship between the change in left-tail risk and expected returns in the Chinese stock market. This effect cannot be explained by the common control variables and existing factor models in China, including the four-factor model (CH4) proposed by Liu, Stambaugh, and Yuan (2019). Additionally, we observe that investors exhibit a stronger preference towards change in left-tail risk for stocks with lower capital gains overhang (CGO).

This paper introduces a method for tunnel point cloud and BIM model integration and cross-section monitoring, providing information to analyse tunnel cross-sections and surrounding rock deformation, and support for tunnel maintenance and reconstruction. Three types of data are processed for the integration: laser scanning point cloud, BIM tunnel model and terrain model from oblique photogrammetry. An adaptive BIM modelling scheme is proposed for tunnels with alien structures. Precise spatial registration of the data sets is conducted by applying singular value decomposition (SVD) algorithm to calculate transformation parameters from the point cloud model to the BIM model. Since the tunnel central line has high-order derivability, a cross-section calculation method based on tangent vector is proposed to obtain the cross-sectional profile of tunnels at any mileage. The proposed method has been verified by applying it to a tunnel reconstruction project. The experiment results show that the tunnel point cloud and the BIM model were highly coincident after the integration. The developed program can effectively get the cross-section of the tunnel at any mileage, and correctly express the spatial relationship between the BIM tunnel, the point cloud of tunnel and the external mountainous terrain.

Using the Wong formula, fusion cross sections of $^{18}\mathrm{O}+^{63}\mathrm{Cu},\phantom{\rule{0.28em}{0ex}}^{18}\mathrm{O}+^{194}\mathrm{Pt},\phantom{\rule{0.28em}{0ex}}^{16}\mathrm{O}+^{208}\mathrm{Pb}$, and $^{12}\mathrm{C}+^{141}\mathrm{Pr}$ reactions are calculated with double-folding potentials (M3Y) and inclusion of the corrected temperature-dependent repulsive nuclear potential (M3Y $+$ rep). Two different values of repulsive diffuseness are selected in calculations and effect of nuclear temperature on the repulsive nuclear potential, the effective potential, and three parameters of the Wong formula are investigated. Our results show that the inclusion of temperature-dependent repulsive nuclear potential increases the effective potential in interior regions, noticeably. However, in the near-barrier region, little enhancement of the effective potential causes small variations in the barrier height, position, and frequency. Better agreement between theory and experiment is observed by including the repulsive nuclear potential.

Yapı sistemlerin doğrusal olmayan analizinde kesit analizi, önemli bir yer tutar. Betonarme kesitlerin analizi, çok sayıda değişkene ve doğrusal olmayan malzeme modeline bağlı olarak, karmaşık iterasyon yöntemleriyle gerçekleştirilir. Bu nedenle, moment-eğrilik bağıntısının el hesabıyla yapılması pratik değildir. Kesit analizi yapabilen programların ortaya çıkmasıyla ve bazı programlara da kesit analizi yapabilme özelliği eklenerek bu sorun bir ölçüde çözümlenmiştir. Bu çalışmada, eksenel yük ve eğik eğilme etkisindeki betonarme dikdörtgen kesitlerin analizini gerçekleştirebilen bir program geliştirilmiştir. Bu programla farklı kesit özelliklerine sahip kolonların kesit analizi gerçekleştirilmiş ve moment-eğrilik ilişkileri belirlenmiştir. Bu ilişkiler pekleşmesiz ikili doğrusal moment-eğrilik ilişkisine dönüştürülmüştür. Bu ilişki kullanılarak; kesitin akma eğriliği, göçme eğriliği ve akma momenti belirlenmiştir. Bu bilgiler ışığında, girdi ve çıktı parametreleri kullanılarak bir YSA modeli eğitilmiştir. Eğitimin ardından, analitik ve YSA modeli karşılaştırılmıştır. Sonuç olarak, eğik eğilme altındaki dikdörtgen kesitli betonarme kolonların moment-eğrilik ilişkisini belirleyebilen YSA modeli önerilmiştir., Cross-section analysis have an important place in nonlinear analysis of building systems. Analysis of reinforced concrete (RC) sections is carried out by complex iteration methods, depending on a large number of variables and nonlinear material models. Therefore, it is not practical to perform the moment-curvature relation by hand calculation. This problem has been solved to some extent with the development of discrete softwares performing cross section analysis, and the upskill to perform cross section analysis of some softwares. In this paper, a program has been developed that can analyze RC rectangular sections under the effect of axial load and biaxial bending. With this program, cross-section analysis of columns with varying cross-section properties was performed and moment-curvature relations were determined. These relations were transformed into a bi-linear moment-curvature relationship ignoring strain-hardening effect. Then yield curvature, failure curvature, and yield moment of the cross section were determined using these relationship. In the light of these data, an ANN model was trained by using input and output parameters. The results of analytical and the trained ANN model were compared. As a result, an ANN model is proposed to determine the relation of the moment-curvature of RC rectangular columns under biaxial bending.

This work deals with the new cross section data obtained for the natV(p,x)43Sc nuclear reaction. We focus on this specific channel because we found a significant discrepancy with a recent NIM B publication, reporting extensive data on activation cross-sections induced by proton-Vanadium collisions up to 65 MeV. Proton-irradiation and γ -spectrometry were performed at ARRONAX facility (Nantes, France) by means of activation of stacked-foils targets up to 70 MeV. Our new experimental values are compared with all the previous measurements and supported by the results obtained with the reaction codes FLUKA, EMPIRE and TALYS. A discussion is given about the possible origin of the observed discrepancy.

The painting View of Lake Sortedam from Dosseringen Looking towards the Suburb Norrebro outside Copenhagen from 1838 by the Danish artist Christen Kobke was subjected to technical investigation by IR imaging techniques, cross section analysis, XRF analysis, and Raman spectroscopy. The genesis of the painting is described as well as the results of the pigment analyses suggesting colour changes in certain areas of the composition related to deterioration of the pigment Prussian blue. The admixture of the blue pigment with white as a determining factor in the fading is proposed, and reports from experimental studies and early documentary sources regarding the permanence of Prussian blue are cited. The implications of the colour changes for the interpretation of the image are suggested.

As a basis for yarn evenness measurement, a novel method based on two orthogonal charge-coupled device (CCD) sensors has been devised. We present a system for analyzing yarn evenness from the coefficient of variation of yarn perimeter, treating the yarn cross-sectional shape like an ellipse with uneven edges. The system architecture, algorithm flow, mathematical principle, and the experimental validation of the proposed technique are presented. A comparison between the proposed method and the conventional Uster Tester 5 and Lawson-Hemphill was made. Results agree quite well with existing methods hence can be implemented as an alternative technique for yarn evenness quantification.

The intent of this paper is to provide empirical evidence of determinants on new business formation in the Czech Republic’s regions in the period 2003 to 2014. The results suggest that the regions with strong entrepreneurial culture, measured by a high proportion of entrepreneurs in the population, and with a strong presence of foreigners, had higher rates of new business formation. A positive influence of agglomeration economies was observed, and the impact of unemployment was negative. However, the results were not consistent when more advanced legal business forms (especially limited liability and joint-stock companies) had been used in the dependent variable. In this case, human capital was the overriding factor determining regional differences in new business formation rates, while entrepreneurial culture and the presence of foreigners were not significant. Finally, the importance of the industrial structure of regions was confirmed regardless of the dependent variable form.

We investigate the cross-sectional and time-series determinants of idiosyncratic volatility in the Korean market. In particular, we focus on the empirical relation between firms’ asset growth rate and idiosyncratic stock return volatility. We find that, in the cross-section, companies with high idiosyncratic volatility tend to be small and highly leveraged, have high variance of ROE and Market to Book ratio, high turnover rate, and pay no dividends. Furthermore, firms with extreme (either high positive or negative) asset growth rates have high idiosyncratic return volatility than firms with moderate growth rates, suggesting the V-shaped relation between asset growth rate and idiosyncratic return volatility. We find that the V-shaped relation is robust even after controlling for other factors. In time-series, we find that firm-level idiosyncratic volatility is positively related to the dispersion of the cross-sectional asset growth rates. As a result, this study is contributed to show that the asset growth is the most important predictor of firm-level idiosyncratic return volatility in both the cross-section and the time-series in the Korean stock market. In addition, we show how the effect of risk factors varies with industries.

Wind energy stands as one of the most important renewable energy sources. Large scale wind turbine blades are mainly based on fiber reinforced polymer composites, as an efficient way to further imp...

This work describes a cross section analysis using a KRITZ experiment modeled with the MCNP code for different ENDLs. The first goal is to validate the processing cross section at work temperature using the KRITZ benchmark for all the evaluated nuclear data libraries available, ENDF-VII.1, JEFF-3.1, JEFF-3.2, TENDL-2014, TENDL-2015, JENDL-4.0, RUSFOND and CENDL-3 at DEN/UFMG. The second goal is to use the same experiment (geometry, parameters, etc) at KRITZ benchmark and use it for thorium application. The new fuel based on thorium were spiked with different fissile nuclides such as 233 U, 235 U, 239 Pu and 241 Pu at 4% each fuel to increase the initial fission chain until it is self-sustained. The purpose is to compare the cross sections from the different ENDLs and find the most suitable ones. The results show that in the case of any application, the difference between ENDF/B, JEFF, JENDL and RUSFOND libraries are in a reliable interval.

This article discusses the technical examination of five flower and fruit still life paintings by the seventeenth century artist Jan Davidsz. de Heem (1606-1684). The painter is known for his meticulously composed and finely detailed still life paintings and is a master in imitating the surface textures of various fruits, flowers, and objects. Macro X-ray fluorescence (MA-XRF) scanning experiments were supplemented with a study of paint cross-sections and contemporary art technical sources with the aim of reconstructing the complex build-up of the overall lay-in of the composition and individual subjects. MA-XRF provided information on the distribution of key chemical elements present in painting materials and made it possible to recapture evidence of the different phases in the artist's working methods: from the application of the ground layers, to De Heem's characteristic oval-shaped underpaintings, and finally, the superposition of multiple paint layers in the working up of the paintings. SEM-EDX analysis of a limited number of paint cross-sections complemented the chemical images with local and layer-specific information on the microscale, providing more accuracy on the layer sequence and enabling the study of elements with a low atomic number for which the non-invasive technique is less sensitive. The results from this technical examination were in addition compared with recipes and paint instructions, to obtain a better understanding of the relation between the general practice and actual painting technique of Jan Davidsz. de Heem. Ultimately, this combined approach uncovered new information on De Heem's artistic practice and demonstrated the complementarity of the methods.

The CrN thin films were deposited using reactive magnetron sputtering by varying base pressure to investigate the crystal structure, microstructure and composition of thin film. In this work, the films properties were characterized by XRD, FE-SEM and EDX techniques. The crystal structures were obtained the cubic of CrN with the crystal size between 23.23 – 28.25 nm and lattice parameters a = b = c = 4.142 - 4.160 Å. The XRD results indicated that the growth of preferred orientation was changed from (200) to (111) plane with increased the base pressure. The surface morphology of CrN thin films did not affected from base pressure. The thickness of CrN thin films which obtained from cross section analysis was decreased from 1788 to 1745 nm by varying the base pressure. The columnar pattern acccompany with the dense structure were investigated from the cross-section analysis. The Cr composition was substantly decreased whereas theN2 composition were increased which observed from EDX technique.

The present paper gives an overview of surface failures, internal nonconformities and solders joint failures detected by microscopic analysis of electronic assemblies. Optical microscopy (stereomicroscopy) and Fourier-Transform-Infrared (FTIR) microscopy is used for documentation and failure localization on electronic samples surface. For internal observable conditions a metallographic cross-section analysis of the sample is required. The aim of this work is to present some internal and external observable nonconformities which frequently appear in electronic assemblies. In order to detect these nonconformities, optical microscopy, cross section analysis, FTIR-microscopy and scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) were used as analytical techniques.

BACKGROUND AND OBJECTIVES Tumor deposits (TDs) are associated with adverse prognostic factors and decreased survival in colorectal cancer. However, controversy exists regarding their definition, evaluation, and staging categories. This study aimed to determine the survival and recurrence impact of the TD in colon adenocarcinomas; and to determine if TD patients behave similarly to stage IV patients. METHODS Cross-section study from 392 patients with colon adenocarcinoma from 2005 to 2012. We performed survival analysis and further stratified patients considering TD patients as a "stage IV-TD" to demonstrate if they behave similarly than stage IV patients. RESULTS From 392 patients, 204 (52%) were men, the mean age was 57.4 ± 13.9 years and 11.5% of cases had TD. In a multivariate analysis, TD failed to predict mortality and recurrence. Considering cases with TD as stage IV-TD, their mean survival was similar to stage IV patients (69.3 and 64.6 months, respectively) and different to those in stage III (110.5 months), II (135.7 months), and I (114.9 months) (P

Over the past several years, parton distribution functions (PDFs) have become more precise. However there are still kinematic regions where more data are needed to help constrain global PDF extractions, such as the sea quark distributions $\bar{d}$/$\bar{u}$ near the valence region (Bjorken-x $\approx$ 0.1 - 0.3).~Current measurements appear to suggest different high-x behaviors of these distributions, leading to large uncertainties in global fits. The charged W cross section ratio (W$^+$/W$^-$) is sensitive to the unpolarized $u,\;d,\;\bar{u},$ and $\bar{d}$ quark distributions at large $Q^2$ set by the $W$ mass and could help shed light on this discrepancy. The STAR experiment at RHIC is well equipped to measure the leptonic decays of W bosons, in the mid-rapidity range $\left(|\eta| \leq 1 \right)$, produced in proton+proton collisions at $\sqrt{s}$ = 500/510 GeV. At these kinematics STAR is sensitive to quark distributions near Bjorken-x of 0.16. STAR can also measure the W cross section ratio in a more forward bin ranging from 1.1 $< \eta, Comment: Submitted to DIS 2017 Proceedings

Flip chip packaging has gained more acceptance; becoming well known in semiconductor packaging industries, mainly due to the increasing demand in the market for small size packages. The application of copper pillar joint in flip chip packaging has contributed to more challenge in complex failure analysis. Solder void defect in between the copper pillar joint area poses a great risk to device malfunction, especially if the device has been used by customer for quite some time. To assess the quality of copper pillar joint, backend semiconductor chip manufacturers normally will apply electrical testing on the production floor for filtering purpose. However, the electrical testing method may still not be sensitive enough to filter out risky samples with minor or less than 50 percent solder joint crack or solder void samples. The conventional failure analysis method commonly applied by backend assembly house is highly dependent on mechanical cross-section to reveal the copper pillar solder joint interfaces, therefore this method still has high risks of defective unit escaping from failure detection. Cross section analysis also has limitation of only capable of providing one plane interface information, which increases the difficulty in finding roots causes. This paper introduces three dimension computer tomography inspections method to overcome the aforementioned limitation and difficulty. The finding in this study shows that this new method can detect solder defects more accurately by calculating the solder void volume and void propagation direction, which can never be achieved by conventional analysis.