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This study proposes a stochastic optimisation model for the day-ahead scheduling in power systems, which incorporates the hourly demand response (DR) for managing the variability of renewable energy sources (RES). DR considers physical and operating constraints of the hourly demand for economic and reliability responses. The proposed stochastic day-ahead scheduling algorithm considers random outages of system components and forecast errors for hourly loads and RES. The Monte Carlo simulation is applied to create stochastic security-constrained unit commitment (SCUC) scenarios for the day-ahead scheduling. A general-purpose mixed-integer linear problem software is employed to solve the stochastic SCUC problem. The numerical results demonstrate the benefits of applying DR to the proposed day-ahead scheduling with variable RES.

Reliability assessment of generation system is a crucial task used to be done using deterministic approaches. However, due to the practical limitations of these approaches, they have been gradually replaced by probabilistic techniques. Nevertheless, there is a considerable reluctance in many electric power utilities to completely abandon deterministic considerations. To fulfill the industry need, wellbeing analysis has been developed to combine the deterministic and the probabilistic approaches in a single framework. Analytical techniques or Monte Carlo Simulation have been used to evaluate wellbeing indices. However, analytical approaches are complicated and mathematically demanding and simulation technique requires a huge amount of computing time, and large memory size. This still prevents the utilities to benefit from the wellbeing framework. This paper presents a novel Genetic Algorithm (GA) based technique to calculate the wellbeing indices. Hopefully, this will encourage the industry to benefit from the wellbeing analysis. The features of the GA are utilized to collect and identify the health, marginal and at risk wellbeing states and to calculate the associated wellbeing indices. The proposed technique is applied to the IEEE-RBTS and the resulting wellbeing indices are compared to those obtained using a conventional analytical technique. The results show that the outcome of both techniques is virtually identical. The effect of the GA parameters on the wellbeing indices is examined. The proposed GA based technique in the manner applied in this study is simple, practical and valid to calculate the wellbeing indices. جرت العادة على أن يتم تقييم موثوقية نظم الطاقة الكهربائية باستخدام طرق قطعية. هذه الطرق تم استبدالها تدريجيا بطرق احتمالية، و التي لها القابلية لأن تأخذ في الاعتبار مواصفات وحدات التوليد و الأحمال الكهربائية. و لكن هناك تردد كبير من قبل شركات الكهرباء لأن تستبعد الطرق القطعية. لذلك تم استحداث طريقة صحة النظام و هي طريقة تحليلية تجمع بين الطرق القطعية و الاحتمالية داخل نطاق عمل واحد. مؤشرات صحة النظام يمكن أن تحسب باستخدام طرق تحليلية و طرق المحاكاة. و لكن يعيب الطرق التحليلية أنها تحتاج إلى طرق رياضية معقدة أما طرق المحاكاة فإنها تستغرق وقتا و ذاكرة كبيرة لإجراء الحسابات. هذا البحث يقدم طريقة حديثة تعتمد على الخوارزمية الوراثية لحساب مؤشرات صحة النظام. مميزات هذه الخوارزمية تستخدم لتحديد مؤشرات صحة النظام. و قد تم تطبيق الطريقة المقترحة على نظام كهربائي تعليمي، و تم مقارنة النتائج مع مثيلاتها باستخدام الطرق التقليدية. و توضح النتائج بأن النتائج لهاتين الطريقتين متطابقة تقريبا. كما تمت دراسة تأثير معاملات الخوارزمية الوراثية على دقة النتائج و قد أظهرت النتائج مدى سهولة الطريقة المقترحة.

Background The aim of this in vitro study was to evaluate the effect of khat extract on the color stability of five different provisional restorative materials (PRMs). Methods In this study, 50 specimens were fabricated from five different PRMs with different techniques. Twenty specimens were digitally fabricated of poly-methyl methacrylate (PMMA) CAD/CAM milling and 3D printing PRMs, while the other thirty specimens were manually fabricated of three different PRMs: PMMA self-cured (SC) acrylic resin, light-cured (LC) composite, and Bis-acrylic SC composite. Milling and 3D printing machines were used to fabricate the digital specimens, while the manual specimens were fabricated using a metallic mold. The material was placed in the mold, covered by a polyester stripe, and held between two glass slabs with a constant load for 30 s. After setting, the specimens were removed and checked. Ten disc-shaped specimens with 2 ± 0.3 mm thickness and 10 ± 0.3 mm diameter were prepared from each of the tested PRM. Then all the specimens were polished. Five specimens of each PRM were immersed in khat extract, while the other five were immersed in distilled water medium as a control group. The color measurements were recorded before and after 1 and 7 days of immersion using a spectrophotometer. The immersion media were renewed every 24 h and kept along with the specimens at 37 °C. The T test, paired T test, and ANOVA analysis of variance were used to analyze the results. The Bonferroni test was used for post-hoc multiple comparisons. Results The interaction between the tested PRMs, the media, and the duration of immersion time was statistically significant (p < 0.05). PMMA CAD/CAM milling PRM was the most stable in color, and this was statistically significant (p < 0.05). The LC composite PRM composite was the least stable in color and was statistically insignificant (p > 0.05) when compared to the 3D printing and Bis-acrylic SC composite PRMs, respectively. Conclusions This study demonstrated that khat extract medium has a high staining ability on the tested PRMs. CAD/CAM milling PRM was the most stable in color and could therefore be used as a long-term provisional. The increase in immersion time was a significant factor in the color change of the tested PRMs. The color of the 3D-printed PRM was the most affected over time.

Background: Although mood disorders are prevalent among systemic lupus erythematosus (SLE) patients, they are usually underrecognized. This study aimed to estimate the prevalence of anxiety and depression among Saudi SLE patients. Methods: This cross-sectional study was conducted among SLE patients from July 2022 to June 2023 in the Eastern Province of Saudi Arabia. A self-reported questionnaire was used to collect the data through validated tools including the Hamilton Anxiety Rating Scale-A and the Beck Depression Inventory score. Results: There were 133 females (91.7%) and 12 males (8.3%) included in this study. Based on the HAM-A score, 45.5% of participants had an anxiety disorder, and according to the BDI score, 46.2% had a depression disorder. Anxiety and depression were significantly associated with a longer duration of SLE, unemployment status, smoking, and the presence of comorbidities. Moreover, the present study found a significant association between depression and male gender. Conclusion: This study found that Saudi SLE patients have a high prevalence of both anxiety and depression. Therefore, SLE patients should be screened for neuropsychiatric disorders during routine follow-ups and managed as early as possible.

Background Fixed prosthodontics require an accurate impression for the teeth and the area to be restored for the laboratory to fabricate the desired restoration without mistakes. This study evaluated the quality of impressions received by private laboratories for the fabrication of fixed prosthesis by describing the frequency of clinically detectable errors and by analyzing association between the various factors involved. Methods 165 impressions were collected from four dental laboratories. Jaw involved, type of tray, size of tray, number of prepared units, type of impression materials, techniques and viscosity in case of elastomeric impressions and type of prosthesis requested were recorded. Data referring to errors and visible defects including errors in finish line, in preparation area, in silicone impression technique and blood in impression were also documented. Factors affecting errors present were also assessed. Association between dentist gender and experience years and impression errors was assessed. Chi square and Fisher exact tests used to examine the association between categorical variables and outcomes. Results The total of error considering not immediately pouring as an error. Alginate was the most impression used. of impressions evaluated (50.9%), 97% were have at least one visible error; 92.1% had errors in finish line, 53.9% had errors in preparation area and (72.8%) of elastomeric impressions were have at least one error in technique. Blood in impression was detected in 52.1% of impressions. Significant association was found between material type and errors in finishing line and preparation area. Significant relationships were found between gender and errors in silicone impression technique (p < 0.05). Conclusion Within the limitations of this study, high frequency of detectable errors was found in fixed prosthesis impressions received by private dental laboratories. This high frequency is of serious concern, as this will result in poor fitted fixed prosthesis provided to patients.

This thesis presents a rule based expert system for distribution system design based on a number of logical steps that distribution system designers normally take. Contrary to other expert systems, this expert system is capable of selecting a suitable supply arrangement for a load. The system chooses between a radial supply and four supplies with single redundancy: primary selective, primary loop, secondary loop, secondary spot. The selection of the interconnection arrangement is based on importance of the load, acceptable costs, maintenance requirements, load size and voltage level. The distribution of loads over the buses is based on the position and on the maximum load per bus for each voltage level. A distinction is made for the maximum load between static loads and dynamic loads. The programme further assures that polluting loads and sensitive loads will not be fed from the same busbar. The interconnection between busbars and to the point of supply is based on rules used by distribution design engineers. Intermediate voltage levels are introduced when an interconnection through one transformer is not possible.The suggested distribution networks are analysed by a load flow programme and a fault calculation programme. Both the programmes included as a part of the expert system. If the voltage or the fault level violates the design rules the expert system points out the violation and suggests ways of overcoming the problem.As distribution system design is not a problem with single absolutely correct outcome, the expert system generates three design alternatives. The different between them is the way in which the loads are supplied with electricity. Apart from the most suitable arrangement, the second best supply arrangement and completely radial supply arrangement.The expert system has been tested for a few load configurations and requirements, and it has been compared with some existing expert systems for distribution system design.

Trigeminal schwannoma is the second most common schwannoma after vestibular schwannoma. Symptoms vary depending on the anatomical structures affected by the tumor, including facial pain, paresthesia, dizziness and ataxia. The primary goals are controlling the symptoms and the maintenance of cranial nerves’ integrity perioperatively. We report a 39-year-old lady who was complaining of mild right-sided headache, vision and hearing loss, right facial weakness and dysphagia. CT and MRI showed a large dumbbell-shaped tumor originating from the trigeminal fossa abutting the petrous and cavernous carotid artery and extending to the infratemporal fossa. An image-guided endonasal endoscopic removal was successfully done. Image-guided endonasal endoscopic removal of a trigeminal schwannoma abutting the petrous and cavernous carotid artery and extending to the infratemporal fossa is a safe, effective approach, as it offers excellent visualization, accurate localization and safe dissection of the tumor from the critical anatomical neurovascular structures surrounding it.

Whole foods are generally considered healthier choices compared to processed foods. For nutritional consideration, whole wheat bread is recommended over the white bread. However, it has a similarly high effect on glycemic response (GR) as the white bread. This study is aimed at assessing the microstructure of whole wheat flour (WWF), white flour (WF), chickpea flour (BF), their blends, and dough and the GR of the bread made thereof. Scanning electron microscope analysis showed clear distinctions in the microstructure of the three flours. WWF particle size distribution had the widest spread with a polydispersity index (PDI) of 1.0 (±0.0) and wider average diameter, with z value of 1679.5 (±156.3) compared with the particle size of 658.9 (±160.4) and PDI of 0.740 (±0.04) for WF followed by BF with the particle size of 394.1 (±54.9) and PDI of 0.388 (±0.07) (p<0.05). The falling number was significantly (p<0.05) lower for WWF compared to WF or BF, indicating higher alpha-amylase activity. Thus, bread made from WWF without BF substitution exhibited a higher glycemic response similar to the bread made from WF. When partly replaced with BF, the GR of the bread made with WWF or WF reduced significantly (p<0.05) in healthy individuals.

Purposes: The purpose of the research is to test the relationship between the reputation of the auditor's office and the accuracy of his opinion on continuity and the impact of that relationship on the financial failure of the client company.   Theoretical framework: Studying the impact of the financial failure of the client company as an intermediate variable. Where some control variables are included, these were addressed through previous studies through a sample of companies listed on the Iraqi stock market (2017-2020) based on the binary logistic regression model to test the research hypotheses.   Methodology/ Design Approach: Relying on the binary logistic regression model to test and conducting additional analysis to test the research hypotheses.   Results: The results of the research indicated that there is a positive and significant impact of the reputation of the audit firms on the accuracy of their opinion on the continuity hypothesis, as well as the positive impact of the accuracy of the opinion of the Supreme Audit Bureau in the supervision of the auditors of the Bureau, and there is a positive and important impact of the variable of financial default as an intermediary variable between reputation the auditor's office and the accuracy of his opinion on continuity. Finally, the results of the analysis support the positive correlation of the effect of financial failure as a control variable on the accuracy of his opinion on going concern.   Research and practical and social effects: The social effects of research appear by studying the reputation of the auditor and its impact on the continuity or failure of companies listed in the Iraqi Stock Exchange. The value of originality: The research represents a qualitative addition to the research that examined the auditor’s reputation variables and their impact on the continuity of companies.