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Powered Roof Support – Rock Strata Interactions on the Example of an Automated Coal Plough System

of longwall main gates and rock strata failure [ 5 , 6 , 7 , 14 , 15 , 20 ]. 3 Operating characteristics of the plough support Derivation of relevant shield–strata interaction parameters and their actual values are summarised in works by [ 8 , 15 ]. To better illustrate the operating conditions, plots of leg pressure p are provided for five shield units arranged in a line ( Figs. 5 and 6 ) and their operating parameters dependent on the settings in the control programme V-Shield are compiled in Table 2 . Figure 5 Shield leg pressure

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Vehicles leasing operations in Lagos state, Nigeria

Abstract

Vehicle is an important element of transport; and its financing especially in road transport comes in 3 ways; outright purchase, hire purchase and lease. Of all these three methods of road transport financing, leasing has attracted little attention in Nigeria transport research. This study was carried out to examine the development, types and form, operating characteristics and problems of vehicle lease in Lagos State, Nigeria. Aggregate number of vehicle leasing companies in Nigeria from inception to 2018 was obtained from corporate affairs commission (CAC). Four prominent vehicle leasing companies: Cashlink Leasing Plc (CLP), NIKKY Taurus Ltd (NTL), C & I Leasing (CIL) and SAMTL Leasing Ltd (SLL) were purposively selected for the operating characteristics and challenges of the leasing companies. 298 structured questionnaires were administered to the staffs of the selected companies seeking the types and forms of lease and challenges encountered in the course of operation using stratified and simple random samplings techniques. Vehicle leasing started in Nigeria from 1986 with the likes of pine hill leasing, Cashlink leasing, VT leasing in Lagos. Within 1986 and 2018, it has spread to 23 different urban cities and the number has increased to 297 companies in 2018. Operating and finance leases exist in the industry with majority of 91.6% of the companies practice operating lease. The staff strength and fleet size level of the leasing companies varies overtime but positively significant to their operations. However, poor pricing of lease service, inadequate finance of vehicle, default in payment of rental charges and high cost of maintenance minimize leasing service efficiency and effectiveness. It is recommended that government should provide subvention for vehicles acquisition, face-off of racketing vehicles from cites and legislate policy to regulate operational activities (entry and exit) of the companies.

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Receiver Operating Characteristic Analysis for Classification Based on Various Prior Probabilities of Groups with an Application to Breath Analysis

operating characteristic curve. Biometrika , 91 (3), 743-750. Hand, D.J. (1981). Discrimination and Classification (Wiley Series in Probability and Mathematical Statistics). John Wiley & Sons. Kushch, I., et. al. (2008). Compounds enhanced in a mass spectrometric profile of smokers' exhaled breath versus non-smokers as derermined in a pilot study using PTR-MS. Journal of Breath Research , 2, 1-26. Lamoš, F., Potocký, R. (1998). Probability and Mathematical Statistic (Statistical Analysis

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A Comparative Assessment of Operating Characteristics of a Diesel Engine Using 20% Proportion of Different Biodiesel Diesel Blend

Abstract

The objective of the present work is to find out the viable substitute fuel for diesel and control of pollutants from compression ignition engines. Therefore, in this present investigation an attempt has been made to study the effect of 20% proportion of five different biodiesel diesel blend in diesel engine. The 20% proportion of biodiesel such as Jatropha, Pongamia, Mahua, Annona and Nerium and 80% of diesel and it is denoted as J20, P20, M20, A20 and N20 are used in the present investigation. The experimental results showed that the brake thermal efficiency of the different biodiesel blend is slightly lower when compared to neat diesel fuel. However, N20 blend, have shown improvement in performance and reduction in exhaust emissions than that of other biodiesel diesel blends. From, the experimental work, it is found that biodiesel can be used up to 20% and 80% of diesel engine without any major modification.

The conducted experiments were conducted on a four cylinder four stroke DI and turbo charged diesel engine using biodiesel blends of waste oil, rapeseed oil, and corn oil with normal diesel. The peak cylinder pressure of the engine running with bio diesel was slightly higher than that of diesel. The experiments were conducted on a four cylinder four stroke diesel engine using bio diesel made from corn oil.

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Infarct-core CT perfusion parameters in predicting post-thrombolysis hemorrhagic transformation of acute ischemic stroke

-Wilk test. The Mann-Whitney U-test was used to determine the existence of a statistically significant difference in CTPPs between cases and controls. A p value < 0.05 was regarded as statistically significant. The area of the receiver operating characteristic (ROC) curve under the curve (AUC) determined the ability of CTPPs to differentiate between the occurrence and non-occurrence of HT. ROC curve analysis identified optimal cut-off values of CTPPs that predict the onset of HT with the highest sensitivity and specificity. IBM SPSS Statistics (version 20.0, SPSS Inc

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Using the Center for Epidemiologic Studies Depression Scale (CES-D) to Classify Participants of a Questionnaire Survey with Regard to Their Individual Inclination to Respond at Random

: Oficyna Wydawnicza Warszawskiego Uniwersytetu Medycznego. Górkiewicz, M. (2009). Using Propensity Score with Receiver Operating Characteristics (ROC) and Bootstrap to Evaluate Effect Size in Observational Studies. Biocybernetics and Biomedical Engineering, 29(4), 41-61. Górkiewicz, M. (2010). Kognitywistyczne spojrzenie na skale psychometryczne: kiedy trudne jest łatwiejsze od łatwego... In A. Pohl, M. Goc, M. Kittel, T. Konik, & M. Siedlecka (Eds.). Rocznik Kognitywistyczny, IV (pp. 81-86). Krakow, Poland: Wydawnictwo Uniwersytetu

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The clinical relevance of urinary soluble fas (sFas) for diagnosis of bilharzial bladder cancer

BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiol. 1982; 143:29-36. 24. Eissa S, Ahmed MI, Said H, Zaghlool A, El-Ahmady O. Cell cycle regulators in bladder cancer: relationship to schistosomiasis. IUBMB Life. 2004; 56:557-64. 25. Sanchez-Carbayo M, Espasa A, Chinchilla V, Herrero E, Megias J, Mira A, et al. New electrochemiluminescent immunoassay for the determination of CYFRA 21-1: analytical evaluation and clinical diagnostic performance in urine samples of patients with bladder

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Is the SNAP-II score useful for predicting mortality in mechanically ventilated in neonates within the first 12 hours of admission?

independently associated with mortality. Performance of the SNAP-II score was evaluated by assessing discrimination and calibration. Discrimination was tested by the area under the receiver operating characteristic (ROC) curve (AUC), which was also used to identify the best cut-off points of SNAP-II scores [ 6 ]. Acceptable discrimination is represented by an AUC of 0.75 or more [ 7 ]. For calibration, the goodness-of-fit of the model was examined by the Hosmer–Lemeshow test [ 8 ]. This method is useful in assessing deviations between the observed and expected numbers of

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Anti-Müllerian Hormone as a Diagnostic Marker in Egyptian Infertile Polycystic Ovary Syndrome Females: Correlations with Vitamin D, Total Testosterone, Dyslipidemia and Anthropometric Parameters

List of abbreviations AMH, Anti-Müllerian hormone SHBG, sex hormone binding globulin IR, Insulin resistance LDL-C, LDL-Cholesterol PCOS, Polycystic Ovary Syndrome ROC, Receiver Operating Characteristic S.D., Standard Deviation TC, Total cholesterol TG, Triacylglycerols VDR, Vitamin D receptor References 1. Lauritsen MP, Bentzen JG, Pinborg A, Loft A, Forman JL, Thuesen LL, et al. The prevalence of polycystic ovary syndrome in a normal population according to the Rotterdam criteria versus revised criteria including anti

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Utility of body mass index and neck circumference to screen for metabolic syndrome in Thai people

from March 21st, 2012 to April 28th, 2015. Physicians conducted a systemic physical examination of participants including blood pressure, and collected blood samples for fasting blood sugar levels, uric acid levels, lipid profiles, and liver function profiles. A flow diagram of participants is shown in Figure 1 . Figure 1 Flow of participants Sample size Sample size calculations were based on the areas under receiver operating characteristic (ROC) curves (AUC) [ 29 ]. As described earlier, ROC curves were used to summarize the diagnostic accuracy

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