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The purpose of this paper is to compare the performances of np-VP control chart with estimated parameter to the np-VP control chart with known parameter using average time-to-signal (ATS), standard deviation of the time-to-signal (SDTS), and average number of observations to signal (ANOS) as performance measures.

The approach used in this study is probabilistic in which the expected values of performance measures are calculated using probabilities of different estimators used to estimate process parameter.

Numerical results indicate different performances for the np-VP control chart in known and estimated parameter cases. It is obvious that when process parameter is not known and is estimated using Phase I data, the chart does not perform as user expects. To tackle this issue, optimal Phase I estimation scenarios are recommended to obtain the best performance from the chart in the parameter estimation case in terms of performance measures.

This research adds to the body of knowledge in quality control of process monitoring systems. This paper may be of particular interest to practitioners of quality systems in factories where products are monitored to reduce the number of defectives and np chart parameter needs to be estimated.

The originality of this paper lies within the context in which an adaptive np control chart is studied and the process parameter unlike previous studies is assumed unknown. Although other types of control charts have been studied when process parameter is unknown but this is the first time that adaptive np chart performance with estimated process parameter is studied.

The dynamic stability of nano-tubes is an important issue in engineering applications. Dynamic stability of anti-symmetric coupled-carbon nanotubes (C-CNTs)-systems in thermal environment is presented in this paper. In this system, the top and bottom CNTs are subjected to axial harmonic load and action of the viscous fluid, respectively.

The coupling and surrounding mediums of the CNTs are simulated by visco-Pasternak foundation containing the spring, shear and damper coefficients. Based on the Timoshenko beam theory and Hamilton’s principle, the coupled motion equations are derived considering size effects using Eringen’s nonlocal theory. Using the exact solution in conjunction with Bolotin’s method, the dynamic instability region (DIR) of the coupled structure is obtained. The effects of various parameters such as small scale parameter, Knudsen number, fluid velocity, static load factor, temperature change, surrounding medium and nanotubes aspect ratio are shown on the DIR of the coupled system.

Results indicate that considering parameters such as small scale effects, static load factor, Knudsen number and fluid velocity shifts the DIR of C-CNTs to a lower frequency zone.

To the best of our knowledge, analyses of anti-symmetric coupled CNTs have not received enough attentions so far. In order to optimize the nanostructures designing, the main purpose of the present paper is to investigate nonlocal dynamic stability of CNTs subjected to axial harmonic load coupled with CNTs conveying fluid.

The purpose of this paper is to compare the impact of lean six sigma (LSS) implementation carried out in a pharmaceutical unit on the profitability of outpatient and inpatient care before and during the Covid-19 pandemic.

The data were analyzed descriptively to see the development patterns in four periods: before implementation, during the implementation before the pandemic, during the pandemic and during the enforcement of new normal, in general, and by the length of stay (LOS).

The inventory purchase in the pharmaceutical unit dramatically decreased after implementation even during the pandemic and new normal wherein the pre-pandemic it decreased by 27%, during the pandemic 29% and in the new normal 37% compared to pre-LSS. The hospital deficit decreased after implementation before the pandemic by 26% and during the pandemic by 10% from the pre-LSS time. However, during the new normal, the deficit increased by 29%, indicating a diminished effect of LSS on the hospital profits.

This research raised the possible implication that the implementation of LSS needed to be carried out in the entire hospital to have a large effect, especially on the inpatient care and long-term care installations.

This research provided empirical evidence regarding the effect of the Covid-19 pandemic on the ability of LSS at the unit level to provide efficiency at the unit level and the entire hospital at various levels of LOS.

The purpose of this paper is to analyze a squared lattice cylindrical shell under compressive axial load and to optimize the geometric parameters to achieve the maximum buckling load. Also a comparison between buckling loads of a squared lattice cylinder and a solid hollow cylinder with equal weight, length and outer diameter is performed to reveal the superior performance of the squared lattice cylindrical shells.

A cylindrical lattice shell includes circumferential and longitudinal rods with geometric parameters such as cross‐section areas of the rods, distances and angles between them. In this study, the governing differential equation for buckling load which can be presumed as a criterion for designing lattice structures with a specific weight is derived and is used as an objective function in genetic algorithm (GA) method to calculate the optimum geometric parameters of the shell. The optimum parameters were modelled in finite element method (FEM) in order to verify the buckling loads obtained from GA. In another effort, the FEM was applied to analyze the solid hollow cylinders.

The results demonstrate relatively close agreement between the buckling loads obtained from GA and FEM for such shells. It was also shown that latticed cylinders have better performance to carry compressive axial loads than the equivalent solid hollow cylinders with equal weights, lengths and outer diameters.

The studies reported in this paper have been carried out for a single squared lattice shell without using two‐side skins. However, using skins can give better performance in carrying compressive axial loads.

The results in this paper show that this type of effective, economical lightweight and functional structures could be applied as inter‐stages, inter‐tanks, aircraft fuselage, rocket motor cases, pressure vessels and other elements of civil engineering structures in order to have greater strength and lower weight.

Squared lattice cylindrical shell with optimum geometric design could provide the chance for eliminating the stiffeners of shells in aerospace structures in order to decrease the weight and increase the load‐bearing capacity.

The purpose of this paper is to assess the quality of Iranian university libraries.

This first systematic review and meta-analysis were based on the PRISMA guidelines by searching in national and international databases from 2003 to January 2017 with standard Persian and English keywords. Data searching, extracting and quality appraising were completed by two researchers, independently. Any unexpected documents were assessed by a third expert researcher. Data were extracted in accordance with the “Strength of the Reporting of Observational Studies in Epidemiology” checklist after the final selection of appraised documents. Random effects size based on Cochrane test and I² were used for combining the obtained results from different studies together by considering the heterogeneity of studies.

Based on the meta-analysis conducted in 25 (6.42 percent) included studies, the total sample size was estimated. According to three dimensions of LibQUAL, findings of current information control, affect of service and the library as a place were estimated as 5.37 [CI95%: 5.02, 5.73], 6.91 [CI95%: 5.56, 6.26], and 5.46 percent [CI95%: 5.2, 5.73], respectively. Also, mean of service adequacy and superiority gap are equal to 0.07 [CI95%: −0.22, 0.36] and −2.06 [CI95%: −2.89, −1.23], respectively. There was a significant correlation between three dimensions of service quality and service superiority gap of LibQUAL and geographical regions of Iran (p<0.01). Also, a significant correlation was found between the gaps of services and three aspects of LibQUAL model and published years through a meta-regression test (p<0.01).

The results obtained from the present study showed that users are relatively satisfied with the quality of services provided by Iranian university libraries. An improvement in the quality of library services can promote the scientific level of universities.

The results of the present systematic review and meta-analysis study demonstrate a vital connection between primary research studies and decision-making for policymakers in Iranian university libraries to increase quality services.

The Health Sector Evolution Plan (HSEP) is the most recent reform in Iran’s health care system that was launched in May 2014 in all university-affiliated hospitals to reduce health care expenditure for patients, while improving the efficiency and quality of hospital services. The purpose of this paper is to evaluate the impact of the HSEP on the performance of 15 hospitals affiliated with Kermanshah University of Medical Sciences (KUMS), located in the western region of Iran.

The Pabon Lasso model was used to measure the performance of hospitals before and after the implementation of the HSEP in 2013-2014 and 2015-2016, respectively. Three indicators of average length of stay (ALoS), bed occupancy rate (BOR) and bed turnover rate (BTR) were analyzed by the Pabon Lasso model.

The results showed that the average ALoS, BTR and BOR before the introduction of the HSEP were 2.59 days, 92 times and 57 percent, respectively, and the corresponding figures for these indicators after the implementation of the HSEP were 2.61 days, 98.9 times and 59.9 percent. The results indicated that before the introduction of the HESP, 40 percent of hospitals were in zone 1 (poor performance: low BTR and BOR and high ALoS), 27 percent in zone 2, 20 percent in zone 3 (good performance: high BTR and BOR and low ALoS) and 13 percent in zone 4. After the HSEP, the proportion of hospitals in zones 1-4 was 33, 27, 20 and 20 percent, respectively.

This study is the first to use the Pabon Lasso model technique to evaluate the impact of the HSEP on hospitals affiliated with KUMS.

This study attempts to identify the different types of activities that comprise a worker's job, and provide a framework for quantitative definition and segmentation of knowledge works (KWs).

Every KW has two main parts: working with knowledge and establishing communication. Thus, in order to provide an exact definition for the KW it is necessary to calculate the knowledge intensity score of a job (JKIS) and communication intensity score of a job (JCIS). For determining these two parameters precisely, jobs were broken hierarchically to tasks and then activities. To identify these activities, an initial list of activities mentioned in the literature was created and then completed with generalized work activities of O*NET. A six‐step framework for calculating of JKIS and JCIS was proposed and finally, different groups of knowledge workers (KWrs) with respect to JKIS and JCIS were identified by using a clustering method.

This article shows how KW can be defined and segmented based on two dimensions (i.e. knowledge intensity score of a job (JKIS) and communication intensity score of a job (JCIS)). The proposed framework was used to analyze 133 jobs in 11 organizations. Practicality and validity of framework were examined based on this empirical study.

This study is a base for the identification of appropriate managerial frameworks corresponding to each discovered group of KWrs. Using more data can improve the results obtained in this study.

This work emphasizes the importance of defining and clustering KW and proposes a practical method for this aim.

A new framework for the quantification of KW is proposed. This framework is supported by five principles inferred from the literature.

The purpose of this paper (systematic review and meta-analysis) is to synthesize and analyze studies that assessed Iranian hospital efficiency.

A systematic literature search was conducted using both international (the Institute for Scientific Information, Scopus and PubMed) and Iranian scientific (Magiran, IranMedex and Scientific Information Database) databases. The review included original studies that used the Pabon Lasso Model to examine Iranian hospital performance, published in Persian or English. A self-administered checklist was used to collect data. In total, 12 questions were used for quality assessment.

In total, 34 studies met our inclusion criteria. The fixed-effects meta-analysis indicated that 19.2 percent (95% confidence interval (CI): 15.6–23.2 percent) of hospitals were in Zone 1 (poor performance: low bed turnover rate (BTR) and bed occupancy rate (BOR) and high average hospital stay (ALoS)), 23.7 percent (95% CI: 20.1–27.8 percent) were in Zone 2, 31.7 percent (95% CI: 27.7–36 percent) in Zone 3 (good performance: high BTR and BOR and low ALoS) and 25.4 percent (95% CI: 21.7–29.5 percent) in Zone 4.

Results help Iranian health policymakers to understand hospital performance, which, in turn, may lead to promoting greater awareness and policy attention to improve Iranian hospital efficiency.

This study indicated that most Iranian hospitals had sub-optimal performance. Further studies are required to understand factors that explain the country’s hospital inefficiency.

This study aims to demonstrate that orange-derived and lemon-derived systems can be used in continuous processes as efficient adsorbents to the entrapment of some anionic and cationic dyes in the textile dyeing wastewater effluents.

Physically and chemically modified orange and lemon mesocarps are used as natural adsorbents for the cationic dyes Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4 and the anionic dyes Acid Blue 264, Acid Yellow 49 and Acid Red 337, all commonly used in the textile dyeing industry. Adsorption capacities of the orange-derived and lemon-derived adsorbents on the dyes are studied simulating a batch and continuous industrial processes.

Results demonstrate that treated orange mesocarp (orange-derived adsorbent) can adsorb up to 97% of cationic Basic Green 4 in 30 min, whereas the lemon mesocarp (lemon-derived adsorbent) can retain up to 88% within the same time. In the case of anionic, 91% Acid Blue 264 is adsorbed by the orange mesocarp in 15 min, whereas 92% is adsorbed by the lemon homologue within the same time.

As far as the authors know, physically and chemically modified orange and lemon mesocarps have not been used on the removal of cationic (Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4) and anioinic (Acid Blue 264, Acid Yellow 49 and Acid Red 337) dyes of textile dyeing wastewater industry. It is a costless and efficient treatment that supposes, on the one hand, an eco-friendly and feasible process for discolouration of wastewater and, on the other, a valorisation (upcycling) of orange and lemon peels, which are not currently used.