Conditional autoregressive negative binomial model for analysis of crash count using Bayesian methods

In order to improve crash occurrence models to account for the influence of various contributing factors, a conditional autoregressive negative binomial （CAR-NB） model is employed to allow for overdispersion （tackled by the NB component）, unobserved heterogeneity and spatial autocorrelation （captured by the CAR process）, using Markov chain Monte Carlo methods and the Gibbs sampler. Statistical tests suggest that the CAR-NB model is preferred over the CAR-Poisson, NB, zero-inflated Poisson, zero-inflated NB models, due to its lower prediction errors and more robust parameter inference. The study results show that crash frequency and fatalities are positively associated with the number of lanes, curve length, annual average daily traffic （AADT） per lane, as well as rainfall. Speed limit and the distances to the nearest hospitals have negative associations with segment-based crash counts but positive associations with fatality counts, presumably as a result of worsened collision impacts at higher speed and time loss during transporting crash victims.

Variance analysis for passive neutron multiplicity counting

Passive neutron multiplicity counting is widely used as a nondestructive assay technique to quantify mass of plutonium material. One goal of this technique is to achieve good precision in a short measurement time. In this paper, we describe a procedure to derive mass assay variance for multiplicity counting based on the threeparameter model, and analytical equations are established using the measured neutron multiplicity distribution.Monte Carlo simulations are performed to evaluate precision versus plutonium mass under a fixed measurement time with the equations. Experimental data of seven weapons-grade plutonium samples are presented to test the expected performance. This variance analysis has been used for the counter design and optimal gate-width setting at Institute of Nuclear Physics and Chemistry.

A Note on Laplace Transforms of Some Common Distributions Used in Counting Processes Analysis

An important problem of actuarial risk management is the calculation of the probability of ruin. Using probability theory and the definition of the Laplace transform one obtains expressions, in the classical risk model, for survival probabilities in a finite time horizon. Then explicit solutions are found with the inversion of the double Laplace transform;using algebra, the Laplace complex inversion formula and Matlab, for the exponential claim amount distribution.

Inference Procedures on the Generalized Poisson Distribution from Multiple Samples: Comparisons with Nonparametric Models for Analysis of Covariance (ANCOVA) of Count Data

Count data that exhibit over dispersion (variance of counts is larger than its mean) are commonly analyzed using discrete distributions such as negative binomial, Poisson inverse Gaussian and other models. The Poisson is characterized by the equality of mean and variance whereas the Negative Binomial and the Poisson inverse Gaussian have variance larger than the mean and therefore are more appropriate to model over-dispersed count data. As an alternative to these two models, we shall use the generalized Poisson distribution for group comparisons in the presence of multiple covariates. This problem is known as the ANCOVA and is solved for continuous data. Our objectives were to develop ANCOVA using the generalized Poisson distribution, and compare its goodness of fit to that of the nonparametric Generalized Additive Models. We used real life data to show that the model performs quite satisfactorily when compared to the nonparametric Generalized Additive Models.

Improving landscape Characteristics in Port Said’s El Sallam Garden via Observational and Space Syntax Analysis

This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be used to assess the impact of a tree planting design’s spatial configuration on an urban park’s visual fields.Trees play an important role in determining the spatial characteristics of an outdoor space.According to space syntax theory,an urban area is a collection of connected spaces that can be represented by a matrix of quantitative properties known as syntactic measures.Computer simulations can be used to measure the quantitative properties of these matrices.This study uses space syntax techniques to assess how tree configurations and garden area which can affect the social structures of small-scale gardens in Port Said.It also looks at how these techniques can be used to predict the social structures of four garden zones in El Sallam Garden.The study includes an observational and space syntax study through comparative analysis of four garden zones in El Sallam garden.The results of the study show that the area and planting configurations of the garden had a significant effect on the syntactic social and visual measures of the urban garden.The conclusions and recommendations can be a useful tool for landscape architects,urban planners,and legislators who want to enhance public areas and encourage social interaction in urban settings.

Evaluation of trend in semen analysis for 11 years in subjects attending a fertility clinic in India

Aim: The data on semen analysis of subjects attending the Fertility Clinic at NIHFW (National Institute of Health and Family Welfare) Munirka, New Delhi for the last 11 years were analyzed to verify the claims and speculations on declining sperm counts in men. Methods: Approximately 10 % of the records every year starting from 1990 to 2000 (numbering 1176 in total) were randomly selected for analysis. Subjects with azoospermia or severe oligozoospermia were excluded from analysis. Results: The average age of the men attending the infertility clinic was 31.2 years. The average semen volume and sperm count were found to be (2.6 ±0.1) mL and (60.6 ± 0.9) × 106/mL, respectively. No significant decline in sperm counts was observed in any year during the entire study period. Only 1.8 % of the total number of sperm counts in the random sampling were less then 20 × 106/mL. On the basis of WHO criteria on motility, the total percentage of non-progressive and non-motile sperm in the ejaculate was higher (63 %) as compared to the combined categories of slow and rapid linear progressive. Conclusion: The present study has confirmed similar findings from other different countries that declining sperm counts in humans is not a global phenomenon.

Semen analysis from an epidemiologic perspective

The fifth edition of the World Health Organization （WHO） manual for semen analysis includes for the first time reference values for human semen characteristics. This paper considers whether such values will help to resolve the intensely debated data indicating temporal and geographical shifts in sperm counts and hypotheses that anthropogenic activities that result in the release of chemicals into the environment are detrimental to male reproductive health. The reasons that these reference values will not fulfil these purposes are also explained. Although established reference values for semen characteristics are of limited value in analytical epidemiologic research, the WHO guidelines are of utmost importance for supporting the development of appropriate research protocols. Moreover, in spite of its limitations, semen analysis is still a useful research tool in epidemiological research, and no superior alternatives are on the horizon.

Prognostic value of lymph nodes count on survival of patients with distal cholangiocarcinomas

AIM To evaluate the prognostic value of the number of retrieved lymph nodes(LNs) and other prognostic factors for patients with distal cholangiocarcinomas, and to determine the optimal retrieved LNs cut-off number.METHODS The Surveillance, Epidemiology and End Results database was used to screen for patients with distal cholangiocarcinoma. Patients with different numbers of retrieved LNs were divided into three groups by the X-tile program. X-tile from Yale University is a useful tool for outcome-based cut-point optimization. The Kaplan-Meier method and Cox regression analysis were utilized for survival analysis.RESULTS A total of 449 patients with distal cholangiocarcinoma met the inclusion criteria. The Kaplan-Meier survival analysis for all patients and for N1 patients revealed no significant differences among patients with different retrieved LN counts in terms of overall and cancerspecific survival. In patients with node-negative distal cholangiocarcinoma, patients with four to nine retrieved LNs had a significantly better overall(P = 0.026) and cancer-specific survival(P = 0.039) than others. In the subsequent multivariate analysis, the number of retrieved LNs was evaluated to be independently associated with survival. Additionally, patients with four to nine retrieved LNs had a significantly lower overall mortality risk [hazard ratio(HR) = 0.39; 95% confidence interval(CI): 0.20-0.74] and cancer causespecific mortality risk(HR = 0.32; 95%CI: 0.15-0.66) than other patients. Additionally, stratified survival analyses showed persistently better overall and cancerspecific survival when retrieving four to nine LNs in patients with any T stage of tumor, a tumor between 20 and 50 mm in diameter, or a poorly differentiated or undifferentiated tumor, and in patients who were ≤ 70-years-old. CONCLUSION The number of retrieved LNs was an important independent prognostic factor for patients with nodenegative distal cholangiocarcinoma. Additionally, patients with four to nine retrieved LNs had better overall and cancer-specific survival rates than others, but the reason and mechanism were unclear. This conclusion should be validated in future studies.

Normal Reference Value of Red Blood Cell Count of Chinese Presenile Men and Geographical Factors

This paper aims at providing a scientific basis for unifying the normal reference value standards of red blood cell count of Chinese presenile men. The paper, using microscopical counting method, studies the relationship between the normal reference values of 38,061 samples of red blood cell count of presenile men and eight geographical factors in 297 units in China. It is found that the correlation of geographical factors and the normal reference value of red blood cell count of presenile men is quite significant （F=303.00, P=-0.000）. By using the method of stepwise regression analysis, one regression equation is inferred. It is concluded that if geographical data are obtained in a certain area, the normal reference value of red blood cell count of presenile men in this area can be reckoned by using the regression analysis. Furthermore, according to the geographical factors, China can be divided into eight regions： Northeast China Region, North China Region, Shanxi-Shaanxi-Irmer Mongolia Region, Middle and Lower Reaches of the Changjiang River Region, Southeast China Region, Northwest China Region, Southwest China Region and Qinghai-Tibet Plateau Region.

Usage Count： A New Indicator to Detect Research Fronts

Purpose： Research fronts build on recent work, but using times cited as a traditional indicator to detect research fronts will inevitably result in a certain time lag. This study attempts to explore the effects of usage count as a new indicator to detect research fronts in shortening the time lag of classic indicators in research fronts detection. Design/methodology/approach： An exploratory study was conducted where the new indicator ＂usage count＂ was compared to the traditional citation count, ＂times cited,＂ in detecting research fronts of the regenerative medicine domain. An initial topic search of the term ＂regenerative medicine＂ returned 10,553 records published between 2000 and 2015 in the Web of Science （WoS）. We first ranked these records with usage count and times cited, respectively, and selected the top 2,000 records for each. We then performed a co-citation analysis in order to obtain the citing papers of the co-citation clusters as the research fronts. Finally, we compared the average publication year of the citing papers as well as the mean cited year of the co-citation clusters. Findings： The citing articles detected by usage count tend to be published more recently compared with times cited within the same research front. Moreover, research fronts detected by usage count tend to be within the last two years, which presents a higher immediacy and real-time feature compared to times cited. There is approximately a three-year time span among the mean cited years （known as ＂intellectual base＂） of all clusters generated by usage count and this figure is about four years in the network of times cited. In comparison to times cited, usage count is a dynamic and instant indicator. Research limitations： We are trying to find the cutting-edge research fronts, but those generated based on co-citations may refer to the hot research fronts. The usage count of older highly cited papers was not taken into consideration, because the usage count indicator released by WoS only reflects usage logs after February 2013. Practical implications： The article provides a new perspective on using usage count as a new indicator to detect research fronts.Originality/value： Usage count can greatly shorten the time lag in research fronts detection, which would be a promising complementary indicator in detection of the latest research fronts.

Theoretical Analysis on Thermal Choking in Expanding RBCC Duct

A one-dimensional theoretical model was adopted in this paper to describe and analyze the flow in an expanding RBCC(rocket based combined cycle)duct.It can be concluded that the expanding angle,heating amount and distribution of heating play crucial roles on the thermal choking.They mainly influence the acceleration of flow,the position of choking throat and the total pressure loss.In order to fulfill the transition of subsonic flow to supersonic flow in the expanding RBCC duct,the heating amount has to change from a bigger value to a smaller one along the duct.When the thermal choking occurs in the RBCC duct,the moderate expanding angle,proper heating amount and distribution of heating are necessary for the best performance of RBCC combustor.Adopting the RBCC duct with smaller expanding angles anterior and bigger expanding angles posterior has positive effects on the thermal choking and flexibility of selecting heating method,and can restrain the negative effect of the combustion on the inlet also.

Pretreatment platelet count improves the prognostic performance of the TNM staging system and aids in planning therapeutic regimens for nasopharyngeal carcinoma:a singleinstitutional study of 2,626 patients

Introduction:Thrombocytosis has been identified as an unfavorable prognostic factor in several types of cancer.This study aimed to evaluate the prognostic value of pretreatment platelet count in association with the TNM staging system and therapeutic regimens in patients with nasopharyngeal carcinoma(NPC).Methods:A total of 2,626 patients with NPC were retrospectively analyzed.Platelet count >300 × 10~9/L was defined as thrombocytosis.Matched-pair analysis was performed between patients receiving chemoradiotherapy and radiotherapy.Results:Multivariate analysis showed that platelet count was an independent unfavorable prognostic factor for overall survival(OS)[hazard ratio(HR) = 1.810,95%confidence interval(CI) = 1.531-2.140,P < 0.001]and distant metastasis-free survival(DMFS)(HR = 1.873,95%CI = 1.475-2.379,P < 0.001) in the entire patient cohort.Further subgroup analysis revealed that increased platelet count was an independent unfavorable prognostic factor for OS and DMFS in patients with NPC stratified by early and advanced T category,N category,or TNM classification(all P < 0.001).Receiver operating characteristic(ROC) curves verified that the predictive value of TNM classification for OS was improved when combined with pretreatment platelet count(P = 0.030).Matched-pair analysis showed that chemoradiotherapy significantly improved OS only in advanced-stage NPC with thrombocytosis(HR = 0.416,95%CI = 0.226-0.765,P = 0.005).Conclusions:Pretreatment platelet count,when combined with TNM classification,is a useful indicator for metastasis and survival in patients with NPC.It may improve the predictive value of the TNM classification and help to identify patients likely to benefit from more aggressive therapeutic regimens.

Bayesian Joint Modelling of Survival Time and Longitudinal CD4 Cell Counts Using Accelerated Failure Time and Generalized Error Distributions

Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical modelling approaches are helpful towards this goal. This study aims at developing Bayesian joint models with assumed generalized error distribution (GED) for the longitudinal CD4 data and two accelerated failure time distributions, Lognormal and loglogistic, for the survival time of HIV/AIDS patients. Data are obtained from patients under antiretroviral therapy follow-up at Shashemene referral hospital during January 2006-January 2012 and at Bale Robe general hospital during January 2008-March 2015. The Bayesian joint models are defined through latent variables and association parameters and with specified non-informative prior distributions for the model parameters. Simulations are conducted using Gibbs sampler algorithm implemented in the WinBUGS software. The results of the analyses of the two different data sets show that distributions of measurement errors of the longitudinal CD4 variable follow the generalized error distribution with fatter tails than the normal distribution. The Bayesian joint GED loglogistic models fit better to the data sets compared to the lognormal cases. Findings reveal that patients’ health can be improved over time. Compared to the males, female patients gain more CD4 counts. Survival time of a patient is negatively affected by TB infection. Moreover, increase in number of opportunistic infection implies decline of CD4 counts. Patients’ age negatively affects the disease marker with no effects on survival time. Improving weight may improve survival time of patients. Bayesian joint models with GED and AFT distributions are found to be useful in modelling the longitudinal and survival processes. Thus we recommend the generalized error distributions for measurement errors of the longitudinal data under the Bayesian joint modelling. Further studies may investigate the models with various types of shared random effects and more covariates with predictions.

Computer Image Analysis as a Tool for Microbial Viability Assessment: Examples of Use and Prospects

Application of the computer image analysis for improving microbial viability assessment by plate count and fluorescence microscopy was investigated. Yeast cells were used as a model microorganism. The application of the improved methods for the viability assessment of yeast cells after preservation by freezing and freeze-drying was demonstrated.

Multi-Scale Network with Integrated Attention Unit for Crowd Counting

Estimating the crowd count and density of highly dense scenes witnessed in Muslim gatherings at religious sites in Makkah and Madinah is critical for developing control strategies and organizing such a large gathering.Moreover,since the crowd images in this case can range from low density to high density,detection-based approaches are hard to apply for crowd counting.Recently,deep learning-based regression has become the prominent approach for crowd counting problems,where a density-map is estimated,and its integral is further computed to acquire the final count result.In this paper,we put forward a novel multi-scale network(named 2U-Net)for crowd counting in sparse and dense scenarios.The proposed framework,which employs the U-Net architecture,is straightforward to implement,computationally efficient,and has single-step training.Unpooling layers are used to retrieve the pooling layers’erased information and learn hierarchically pixelwise spatial representation.This helps in obtaining feature values,retaining spatial locations,and maximizing data integrity to avoid data loss.In addition,a modified attention unit is introduced and integrated into the proposed 2UNet model to focus on specific crowd areas.The proposed model concentrates on balancing the number of model parameters,model size,computational cost,and counting accuracy compared with other works,which may involve acquiring one criterion at the expense of other constraints.Experiments on five challenging datasets for density estimation and crowd counting have shown that the proposed model is very effective and outperforms comparable mainstream models.Moreover,it counts very well in both sparse and congested crowd scenes.The 2U-Net model has the lowest MAE in both parts(Part A and Part B)of the ShanghaiTech,UCSD,and Mall benchmarks,with 63.3,7.4,1.5,and 1.6,respectively.Furthermore,it obtains the lowest MSE in the ShanghaiTech-Part B,UCSD,and Mall benchmarks with 12.0,1.9,and 2.1,respectively.

A Recursive Binary Tree Model for the Analysis of the Response to Antiretroviral Therapy of HIV Infected Adults in Burkina Faso

In this paper we aim to analyse temporal variation of CD4 cell counts for HIV-infected individuals under antiretroviral therapy by using statistical methods. This is achieved by resorting to recursive binary regression tree approach [1]?[2]. This approach has made it possible to highlight the existence of several segments of the population of interest described by the interactions between the predictive covariates of the response to the treatment regimen.

Dynamical Analysis of DC Shunt Motor Powered by PV Generator Using Perturbation and Observation as MPPT Technique

This paper presents the perturbation and observation (P & O) algorithm as maximum power point tracking (MPPT) method for the dynamical analysis of DC shunt motor fed by photovoltaic generator at different solar irradiance levels. At each solar intensity, the maximum power point of current/voltage (I/V) characteristic of the PV generator is achieved by perturbation and observation algorithm. The nonlinear behavior of (I/V) characteristics of the PV generator at various solar intensities and the magnetization curve of the ferromagnetic material of the DC shunt motor are described by high order polynomial mathematical expression. The dynamical analysis of the DC shunt motor fed by PV generator at different solar intensity has been carried out, also the dynamical analysis of DC shunt motor is investigated at a step change in solar intensity levels with fixed load at motor.

Comparative Analysis of Technical Parameters of Different Knitted Structures (Jersey, Pique and Lacoste) with or without Lycra/Spandex

The relationship of Count, GSM (Gram per Square meter), and Stitch Length, Shrinkage%, spirality% and pilling are discussed by this paper among Pique, Lacoste and Jersey knit structures with or without Lycra “3% - 5%”. For this research, we used different knitted structures, yarn count and stitch length and for finding data different types of m/c are used which are discussed later. This study is based on finish GSM of Pique, Lacoste and Jersey Knit Fabrics where various kinds of yarn count, GSM and Stitch length are used to justify the experiment. The relation of count and Stitch length with GSM is inversely proportional. When count and Stitch length increases, GSM decreases which is proved through this paper by using both the expected and experimental data. For writing this paper we have distinguished both the theoretical as well as practical implications from the industry and tried to find out adjustable points of fabrics Count, GSM and Stitch Length along with Shrinkage%, Fabric width, Spirality. This paper provides a reliable result which will help selection of count, GSM and Stitch length for making of Pique, Lacoste and Jersey knit fabrics with or without Lycra maintaining the Shrinkage%, spirality%, pilling grade in an acceptable limit. This paper logically shows that GSM, shrinkage and spirality vary when structure, yarn count, and stitch length vary.

Simulation and Experimental Analysis of Vortex Tube Using Steel Material

Experimental and computational fluid dynamics (CFD) are investigated through the vortex tube system. The benefit of vortex tube is a counter flow type tube, which has further designed and fabricated for investigation. The whole set up is consisting of a simple device that can separate a single stream of compressed air into two streams;one is at high temperature and the other is lower temperature following an inlet gas stream. The advantages of this tube are their compactness, safety, and low equipment cost mainly used in cooling and heating applications. This study addressed three-dimensional flows;the domain is using computational fluid dynamics (CFD) method and experimental approach to optimize the direction of RHVT. Through the CFD analysis, the best cold end diameter (dc), number of nozzles, and the best parameters for obtaining the highest hot gas temperature and lowest cold gas temperature were obtained and verified by experimental procedures.