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Current studies on scheduling of machines and transporters assume that either a single transporter or an infinite number of homogeneous transporters such as AGVs or mobile robots are available to transport semi-finished jobs, which seems very restrictive in practice. This paper addresses this gap by studying a job-shop scheduling problem that incorporates a limited number of heterogeneous transporters, where the objective is to minimize the makespan. The problem is modelled using mixed-integer linear programming and constraint programming. Different structure-based branch-and-bound algorithms with two lower-bounding strategies are also developed. A comprehensive numerical study evaluates the proposed models and algorithms. The research demonstrates that the adjustment of the proposed MILP model outperforms the existing formulation when applied to the homogeneous case. The study also uncovers interesting practical implications, including the analysis of the impact of different transporter types in the system. It shows that utilizing a fleet of heterogeneous transporters can improve the overall performance of the job shop compared to a relevant homogeneous case. The importance of the study is emphasized by highlighting the negative consequences of disregarding transporters' differences during the scheduling phase. [ABSTRACT FROM AUTHOR]

Investigations have shown the traces of antibiotics in surface water, groundwater, wastewater treatment plants, and drinking water. However, conventional wastewater treatment is not entirely effective for vancomycin degradation. Advanced oxidation is one of the most widespread methods of antibiotic degradation in aqueous media. Vancomycin was quantified by high-performance liquid chromatography. The Response Surface Methodology (RSM) based on Central Composite Design (CCD) was used to explore and optimise the effect of the independent variables on vancomycin degradation. Independent variables were as follows: pH (3–11), vancomycin concentration (15–75 mg/L), TiO2–clinoptilolite (25–125 mg in 250 mL reactor volume), the temperature (25–45°C), and the reaction time (15–75 min). The validity and adequacy of the model were confirmed by the corresponding statistics (F–value = 111.5, correlation coefficient R2 = 0.98, adjusted R2 = 0.97, and prediction R2 = 0.95). The vancomycin degradation efficiency was 97% under optimal conditions (pH = 5, vancomycin concentration = 30 mg/L, TiO2-clinoptilolite content = 50.2 mg in a 250 mL reactor volume, temperature = 32.24°C, and reaction time = 50.9 min). This process followed the zero-order reaction kinetics model (R2 = 0.98), and the removal rate of Total Organic Carbon (TOC) under optimal conditions was 56%. The results indicated that supporting TiO2 on clinoptilolite particles could increase the photocatalytic properties. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare the outcomes, success rate, and complications of performing elective ureteroscopy at different times: <1 week from renal colic initiation (early) and more than 1 week from renal colic initiation (late) in patients with ureteral stone larger than 6 mm. Materials and Methods: This comparative observational study was conducted on 338 consecutive patients. Patients were evaluated in two groups: patients who underwent ureteroscopy in <1 week (A) and patients who underwent ureteroscopy in more than 1 week (B) from renal colic initiation. Helical unenhanced computed tomography was used to assess the size, location, and hardness of stone for all patients. Operation success was defined as complete clearance of stone with no stone residue (stone free) at 2-week postoperative ultrasonography with no need to further interventions. Operation data were collected using medical records, and postoperative complications were investigated at 2 weeks postoperative follow-up visits. Results: Group A included 165 patients and Group B included 173 patients. The overall mean stone size was 8.60 ± 1.12 mm: for Group A 9.13 ± 0.94 mm and for Group B 8.10 ± 1.04 mm (P < 0.001). Stone residues were found in 11 patients: 9 in Group A (5.4%) and 2 in Group B (1.1%) (P = 0.026). Nine patients needed repeated ureteroscopy: 8 (4.8%) in Group A and 1 (0.6%) in Group B (P = 0.015). A double-J stent was used for 85 (51.5%) patients in Group A and 66 (38.2%) patients in Group B (P = 0.016). Major intraoperative complications did not happen in any patients. Fifty-three (32.1%) patients in Group A and 28 (16.2%) patients in Group B suffered from postoperative complications (P = 0.001). Conclusion: Our study revealed that performing elective ureteroscopy with an interval of more than 1 week from the onset of renal colic in combination with medical treatments was associated with less need for double-J stent placement, less need for repeated ureteroscopy, and fewer postoperative complications compared to performing elective ureteroscopy in <1 week from the renal colic onset in nonemergent patients with ureteral stone larger than 6 mm. Although the rate of ureteroscopy failure was higher among the patients who underwent ureteroscopy in <1 week from their renal colic initiation, there was no statistically significant relationship between performing ureteroscopy in <1 week and an increased risk for ureteroscopy failure. [ABSTRACT FROM AUTHOR]

Purpose: The choice between using the internal or external iliac arteries to supply a transplanted kidney poses a dilemma during renal transplantation. As the internal iliac artery branches to the genital tract, cutting it could potentially result in sexual dysfunction. The purpose of this study was to compare the effects of these two surgical methods on sexual function. Materials and Methods: 122 sexually active male patients under the age of sixty were randomly divided into two groups: the internal iliac anastomosis group and the external iliac artery anastomosis group. Before surgery and one year after the procedure, patients completed the International Index of Erectile Function-15 questionnaire (IIEF-15), and the difference in scores of each domain was measured. Results: Statistically, kidney transplantation improved all domains of IIEF in both groups, except for erectile function in patients who underwent internal iliac artery anastomosis group. Additionally, there were significant differences between the two groups in the domains of erectile function (p-value=0.04) and overall satisfaction (p-value = 0.002), while other domains such as orgasmic function, sexual desire, and intercourse satisfaction did not show any statistically significant differences. Conclusion: In conclusion, the choice between using the internal or external iliac artery for arterial anastomosis during kidney transplantation does not significantly impact graft function. However, it may negatively affect erectile function in patients who undergo internal iliac artery anastomosis. [ABSTRACT FROM AUTHOR]

A rational method for estimating soil suction variations within the so-called moisture active zone or vadose zone is required. Within the unsaturated zone, a soil suction envelope is defined by the maximum and minimum suctions at the ground surface (i.e., the suction amplitude), equilibrium suction, and depth to the equilibrium (or constant) suction. This paper presents a mechanistic-numerical model for predicting equilibrium suction that takes into account the effects of the diffusion coefficient and makes use of surface field suction measurements. The rational attenuation function in this study represents the rate of suction change within the unsaturated zone. The model can predict the equilibrium suction in response to changes in the subgrade moisture regime. The geographic information system (GIS) platform was used to create contour maps of the mechanistic-numerical equilibrium suction values for Oklahoma. In addition, the paper presents a reliable statistical-based equilibrium suction prediction model based on readily available parameters such as Thornthwaite Moisture Index (TMI), clay content, and relative humidity. [ABSTRACT FROM AUTHOR]

This paper studies an unequal area layout problem whose objective is to find a flexible bay layout with the best shortest single loop. The problem can be used for production systems in which material handling is carried out by automated guided vehicles (AGVs) that move along a single-loop path. The designed layout is robust against future changes in material flows, which are caused by different factors such as demand fluctuations, technology advancement, and new product introduction. It is first proved that there exists a feasible single loop for any bay layout, which indicates the problem is well-defined and always has a feasible solution. Then, a powerful hybrid algorithm based on Memetic and Simulated Annealing is developed. The algorithm is tested on many randomly generated instances and well-known instances from the literature. The numerical experiment shows that the proposed heuristic is both efficient and effective. The new layout-design approach significantly improves the loop-length when compared with the traditional approach in which the layout is first determined based on rectilinear distances, and then the best single loop is found. Our study highlights the importance of adequately incorporating the material handling system into the layout design phase. [ABSTRACT FROM AUTHOR]

We developed a novel three-dimensional graphene oxide/allylamine/allyl glycidyl ether, and evaluated its adsorption performance for humic acid removal in an aqueous solution. The effective parameters were optimized by the Taguchi design method. Effective parameters on the removal of humic acid, including adsorbent dosage, solution pH, contact time, and temperature were evaluated using an L9 orthogonal array. The optimum parameters were adsorbent dosage of 0.02 g, pH of 6, contact time of 120 min, temperature of 25°C, and the removal efficiency of humic acid was 58%. Also, analysis of variance showed the most significant factors were adsorbent dosage and contact time with 33.58% and 51.62% contribution, respectively. The prepared nanoadsorbent was characterized by Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy with energy-dispersive X-ray analysis, and thermogravimetric analysis. The equilibrium data were evaluated by different isotherm models, where the data followed a Langmuir model with a maximum sorption capacity of 25.97 mg/g. Also, the kinetic adsorption data were well evaluated by the pseudo-secondorder model. The thermodynamic data shown that the sorption of humic acid onto the nanoadsorbent was an exothermic, favorable, and spontaneous process. The regeneration test indicated that the nanoadsorbent could be reused in the water treatment application. This study concluded that nanoadsorbent is a very hopeful nanoadsorbent for the remediation of water polluted by humic acid. [ABSTRACT FROM AUTHOR]

The use of Orbal reactors for wastewater treatment by activated sludge is deemed efficient by various literature sources. Furthermore, it is interesting to determine the potential methodologies to improve removal efficiencies. This study aims to investigate the performance of removal efficiency when a magnetic field is incorporated within the reactor. In this experiment, two magnetic fields of different intensities (1.3 and 2 mT) were used. To generate these magnetic fields, several neodymium magnets were applied to the reactor. The experiment and sampling lasted approximately over a 156-d period to observe the performance of the reactor, with and without the application of a magnetic field. Upon the reactor achieving a steady-state, results were taken. It should be highlighted that, before application, four different inflows were discharged into the reactor to attain the optimum retention time. To confirm the validity, results from relatable studies were compared with this study's findings. Upon application of the magnetic fields, removal efficiencies of total nitrogen, chemical oxygen demand, and biochemical oxygen demand for five days increased by 11%, 6%, and 7%, respectively. Nitrate concentration in effluent had decreased by 21%. Furthermore, the food to microorganism ratio had decreased within a 13%-15% range. Results indicated, also, that the application of different strength magnetic fields had minor effects on removal efficiency. [ABSTRACT FROM AUTHOR]