Experimental modelling of evaporation and boiling processes in a two-phase thermosyphon

A model of a closed two-phase thermosyphon was developed to study thermo-physical processes in a thermosyphon thermal condition systems of energy-saturated equipment. This model differs from the known by reasoned choice of thermocouples installation providing sealing the device during operation. In addition, the program VI (Virtual Instrument) was created in graphical environment Labview for registration of the temperatures and pressure in the thermosyphon

Racial and ethnic disparities in pelvic floor disorder awareness

Objectives: Pelvic floor disorders (PFD) affect the quality of life for many women and can be a significant cause of distress. With the United States’ aging population, PFD are becoming increasingly prevalent. Previous population based studies identified both differences in prevalence and baseline knowledge of PFD by race and ethnicity. These prior studies assessing PFD knowledge were limited to single geographical areas or institutions. We aim to conduct a multicenter study across the United States to better understand the baseline knowledge and perceptions of PFD and its variance across different races and ethnicities. Our goal is to provide data that will help deliver culturally competent information to patients. Materials and Methods: This was a multicenter cross-sectional study involving six sites. Upon initial presentation to a urogynecology clinic, patients were evaluated with the Prolapse and Incontinence Knowledge Questionnaire along with additional questions aimed to assess differences in PFD descriptive language, barriers to care, and attitude towards PFD. Surveys were distributed at participating institutions from October 2019 to February 2021. Statistical analyses were performed with Fisher\u27s exact test and Chi-square test, using p \u3c0.05 for statistical significance. Results: A total of 287 women completed the survey, with 27 excluded due to omission of race and or ethnicity responses. Respondents identified their ethnicity as Hispanic (21.8%) and race as White (70.5%), African American (AA) (19.2%), and Other Women of Color (OWOC) (10.3%). Overall, the mean percent correct for the urinary incontinence (UI) and pelvic organ prolapse (POP) sub-scores were 61.2 ± 28.2 and 60.5 ± 28.2, respectively. AA and OWOC had lower scores compared to White respondents in both UI (AA 60.7 ± 30.1; OWOC 46.8 ± 31.2; W 63.5 ± 26.5; p = 0.018) and POP (AA 55.5 ±30.1; OWOC 48.9 ± 31.0; W 64 ± 26.2; p = 0.011). Hispanic women scored lower in both UI (43.9 ± 29.8 vs 66.5 ± 25.3, p \u3c0.001) and POP (46.2 ± 28.4 vs 66.5 ± 25.3, p\u3c0.001) when compared to non-Hispanic respondents. AA and OWOC had decreased knowledge of POP language compared to White respondents (32.3 ± 30.8 % correct vs 35.4 ± 33.6 % correct vs 50.4 ± 32.9 % correct, p \u3c0.001). This was similar for Hispanic compared to non-Hispanic respondents (33.3 ± 31.2 % correct vs 40.1 ± 32.5 % correct, p\u3c0.001). Responses to UI and POP misconception questions were not different by race or ethnicity. Conclusion: This is the first multicenter, cross-sectional survey of a diverse patient population assessing knowledge and perception of PFD. We observed differences between baseline knowledge and language proficiency of PFD amongst AA, White, and OWOC, as well as between Hispanic and non-Hispanic women. This suggests the presence of racial disparities in women pursuing urogynecologic care and highlights the importance of delivering culturally sensitive information to educate women of diverse backgrounds

Aggregate production planning considering performance evolution : a case study

Due to the violent market competition, organizations should respond quickly to customer needs. This strategic objective can be reached through the development of robust production planning. One of the most important factors in production planning is the workforce productivity which is a dynamic manufacturing property, i.e. the workforce productivity increases thanks to in-job training. This phenomenon is known as production progress function or work-based-learning. Considering this phenomenon in industrial planning can lead to robust manufacturing plans. The current study introduces a novel model for a medium term production planning, which used to find the yearly optimum aggregate production plan in order to minimize the total production costs in respecting the operational constraints and considering the production progress function. The resultant model is a linear mixed integer program that can be solved optimally. The data used in validating and running the model was taken from an Egyptian factory that is dedicated to produce electric motors. The model was solved optimally using ILOG CPLEX Software. By comparing the results of this study against the adopted approach in the factory; one can find that the model succeeded to minimize the production costs by about 5.43 % for first year, 2.66% for the second, and 1.86% for the third one. In monetary units these percentages can be translated respectively to 11.7 million L.E., 6.3 million L.E., and 4.7 million L.E

Descomposición térmica de aceite de germen de arroz para su uso como gasóleo

Ricebran oil; a non edible oil, was thermally decomposed using different loads of calcium oxide as catalyst. The fuel properties of the cracked product were evaluated as compared to those of diesel fuel. The considered properties included the calorific value, flash point, viscosity, pour point, distillation characteristics, cetane number in addition to some other fuel properties. The results had shown that the fuel properties of the decomposed oil were quite similar to those of standard diesel fuel. The calorific value was 80-90% that of diesel fuel and the viscosity was sligthy higher. The prepared fuel was advantageous over diesel fuel as the former was completely free from sulfur, which on fuel combustion produces corrosive gases of sulfur oxides.Aceite de germen de arroz, un aceite no comestible, fue descompuesto térmicamente usando diferentes cantidades de óxido cálcico como catalizador. Las propiedades combustibles del producto craqueado fueron evaluadas comparándolas con las del gasóleo. Las propiedades consideradas incluyeron el poder calorífico, punto de inflamación, viscosidad, temperatura de fluidez crítica, características de destilación, número de cetano y otras propiedades de los combustibles. Los resultados han mostrado que las propiedades combustibles del aceite descompuesto fueron bastantes similares a la de los gasóleos estándar. El poder calorífico fue del 80-90% de la del gasóleo y la viscosidad ligeramente mayor. El combustible preparado fue ventajoso sobre el gasóleo ya que el primero estaba completamente libre de sulfuro, el cual produce en la combustión del carburante gases corrosivos de óxido de azufre

Development of A New Local Mineral Admixture for Enhancing Concrete properties

Proceeding from the saying of our God almighty on his book, the holy Qur'an: "Then ignite for me, O Hāmān, (a fire) upon the clay (From which bricks are made) and make for me a tower....". Therefore, this paper presents an investigation on, using calcined ball-clay (CBC) as mineral pozzolanic admixture for concrete production. CBC is obtained from calcination processes for local ball-clay at specified conditions. To evaluate ball-clay calcination process, various temperatures (600–900 ºC) and burning durations (2, 3 and 4 hours) are used and the optimum temperature and burning time for calcination are assessed by strength activity index at age of 28 days. The hardened properties development of concrete mixtures containing 0%, 10%, 15% and 20% CBC as cement partial replacement are analysed in terms of compressive strength at 7, 28, 90 and 180 days, water absorption, ultra-sonic pulse velocity and electrical resistivity. In addition, microstructure by XRD of the cement pastes incorporating CBC was studied. The results showed that the optimum calcination process to obtain CBC are carried out at temperature 800 °C for 4 hours. The replacement of cement by 10% of CBC is an optimal dosage for concrete mixtures since it achieved an increase of compressive strength by 28% as compared with control one. Therefore, adding CBC can lead to a beneficial utilization of natural local resources, which reduces energy consumption and minimizes CO2 footprint during the manufacturing of cement concrete, thus, concrete can become an eco-friendly and sustainable material

Academic Achievement and Psychosocial Profile of Egyptian Primary School Children in South Sinai

BACKGROUND: Population of South Sinai has suffered from negligence for many years. Solving educational problems of this population is the main concern nowadays.AIM: To assess academic achievement in primary school children in South Sinai in relation to intelligence and psychosocial profile.SUBJECTS AND METHODS: A descriptive cross-sectional survey was conducted on 407 Bedouin and urban students randomly selected from twelve public primary schools in six cities in South Sinai. Intelligence was assessed using Goodenough-Harris test. The midyear Arabic language and Arithmetic scores were used to assess academic achievement. The teachers completed a Pediatric-Symptom Checklist for evaluation of children behaviour.RESULTS: A statistically significant difference in academic achievement (P < 0.001), total psychosocial scores, (P < 0.05), and externalization (P < 0.05) was found between urban and Bedouin students with significant gender differences (P < 0.05). Highly significant positive correlations were observed between IQ percentile and mid-year Arabic language scores and Arithmetic scores (P < 0.001), and significant negative correlations with the total score of PSCL and its subscale scores (externalising, inattention, and internalising behaviour) (P < 0.001) among the students.CONCLUSION: Comorbid academic and psychosocial dysfunction in primary school children were observed in South Sinai. A national strategy to minimise the educational gap between Bedouin and urban areas should be implemented

Powder Bed Layer Characteristics: The Overseen First-Order Process Input

A discrete element powder model is used in conjunction with a finite volume melting model on the first layer of a powder bed selective laser melting process