Performance and modeling of UV/persulfate/Ce(IV) process as a dual oxidant photochemical treatment system: Kinetic study and operating cost estimation

2018 ◽  
Vol 347 ◽  
pp. 243-251 ◽  
Author(s):  
Ali Reza Soleymani ◽  
Mohammad Moradi
2020 ◽  
Vol 27 (2) ◽  
Author(s):  
Rohana Ahmad ◽  
◽  
Nur Amalina Zul ◽  
Siti Anisah Mohtar ◽  
Marc Tennant ◽  
...  

Objectives: University-led dental clinics are rarely seen as core to the national healthcare system. Thus, when publicly funded universities experience a decline in government support, dental clinic services operated by students are confronted by a potentially inadequate operating budget. Prompted by the need for strategic resource allocation, this study seeks to quantify the resources consumed in the construction of complete dentures by undergraduate students in an effort to identify opportunities for cost-cutting measures. Methods: Clinical cases were retrieved from the logbooks of graduating students of Class 2015, and patient records were reviewed to identify and quantify all clinical and laboratory procedures involved in constructing a set of complete dentures. Cost estimation was carried out using the activity-based method on the basis of direct medical costs. Results: A total of 83 patient records were reviewed. The average number of visits required to fabricate a set of complete dentures was 10 (range, 6–20 visits) with an average total cost of MYR2131±538 (€450±114). The number of visits contributed substantially to the total cost, and procedures requiring multiple visits included secondary impression and jaw relation recording. The major cost components were dental equipment (44%), laboratory costs (28%), dental consumables (17%), salaries (7%), and dental instruments (3%). Conclusion: The operating cost for training students in denture fabrication is substantial. Schools should formulate strategies to reduce the number of patient visits by ensuring that students optimize the time spent per visit. A financially sustainable model to fund dental training is necessary to ensure that quality of care is not compromised in university-led clinics.


2012 ◽  
Vol 18 (3) ◽  
pp. 378-385 ◽  
Author(s):  
Ahmad Reza Sayadi ◽  
Ali Lashgari ◽  
Mohammad Majid Fouladgar ◽  
Miroslaw J. Skibniewski

Material loading is one of the most critical operations in earthmoving projects. A number of different equipment is available for loading operations. Project managers should consider different technical and economic issues at the feasibility study stage and try to select the optimum type and size of equipment fleet, regarding the production needs and project specifications. The backhoe shovel is very popular for digging, loading and flattening tasks. Adequate cost estimation is one of the most critical tasks in feasibility studies of equipment fleet selection. This paper presents two different cost models for the preliminary and detailed feasibility study stages. These models estimate the capital and operating cost of backhoe shovels using uni-variable exponential regression (UVER) as well as multi-variable linear regression (MVLR), based on principal component analysis. The UVER cost model is suitable for quick cost estimation at the early stages of project evaluation, while the MVLR cost function, which is more detailed, can be useful for the feasibility study stage. Independent variables of MVLR include bucket size, digging depth, dump height, weight and power. Model evaluations show that these functions could be a credible tool for cost estimations in prefeasibility and feasibility studies of mining and construction projects.


2006 ◽  
Vol 128 (07) ◽  
pp. 42-43
Author(s):  
Harry Hutchinson

This article discusses about latest developments in handling medical wastes. The article highlight features of Ecolotec, which is a large autoclave equipped with a system of blades to churn and chop the waste. The waste treatment system is in its final stages of testing and could be on the market soon. Currently, Ecolotec is studying blades of SAE 4140 chromium-molybdenum steel. The blades are sharpened daily with a belt sander, and the company may package one with the system when it reaches the market. Computer control is provided by an Allen-Bradley programmable logic controller (PLC) with a waterproof keyboard. The PLC has a wireless Internet card so, if a customer chooses, Ecolotec will be able to diagnose equipment from its headquarters. Ecolotec's executives say that, at an operating cost of 11 cents a pound, their machine costs considerably less than a waste disposal service.


2003 ◽  
Vol 23 (3) ◽  
pp. 463-473
Author(s):  
Waldir Medri ◽  
Rejane Helena Ribeiro da Costa

This article presents the results from the monitoring of a system of ponds for the treatment of piggery wastes, carried out during a 20 months period, with the objective to determine design parameters for the optimization of the treatment system. A series composed of two anaerobic ponds, one facultative pond and one water hyacinth pond, gave an efficiency of 97% in the removal of BOD5, 93% for total phosphorus, 91% for total Kjeldahl nitrogen and a removal of 7 log units for fecal coliforms. A model of the optimization incurred in the treatment of these wastes was developed, within economic concepts.


Author(s):  
Yunpeng Cao ◽  
Lie Chen ◽  
Jianwei Du ◽  
Fang Yu ◽  
Qingcai Yang ◽  
...  

When a gas turbine operates in a marine environment, gradual performance degradation occurs due to salt fog in the compressor and turbine. Regular water washing of a gas turbine can effectively restore the performance loss caused by compressor salt fog fouling on the flow passage. However, inappropriate washing will increase maintenance costs, cause unnecessary down time and premature erosion of leaf surfaces. In this paper, a coefficient matching method for a three shaft marine gas turbine salt fog fouling degradation factor model is proposed, which can establish a model of salt fog fouling degradation factor according to a change in operating time and exhaust temperature in the washing cycle. The influences of load, environment temperature, inlet pressure loss and salt fog fouling rate on the performance degradation of the gas turbine are simulated and analyzed; then, the degradation regularity of the performance parameters of the gas turbine under different operating conditions and fouling degrees is obtained. Finally, a method of operating cost estimation for marine gas turbines is proposed that can estimate the cost of transient change and cumulative change in the cleaning cycle caused by the salt fog fouling, which can help the operator to determine the cleaning strategy and reduce the operation cost of the gas turbine.


2020 ◽  
Vol 7 (1) ◽  
pp. 439-456
Author(s):  
Nazeri Abdul Rahman ◽  
Nurhidayah Kumar Muhammad Firdaus Kumar ◽  
Umang Jata Gilan ◽  
Elisa Elizebeth Jihed ◽  
Adarsh Phillip ◽  
...  

Due to insufficient water supply, the residents of the rural area of Sarawak are forced to use peat water as daily use for domestic water. The consumption of untreated peat water can lead to various waterborne diseases such as diarrhoea, and other serious illnesses such as typhoid and dysentery. Water treatment system such as electrocoagulation system can be developed to improve the water quality of the peat water as electrocoagulation requires simple equipment that can be operated easily, no usage of chemicals coagulant, producing less sludge and cost-effective treatment system. The main aim of this study is to develop a kinetic study and statistical modelling for both batch and continuous electrocoagulation processes of peat water treatment in Sarawak using aluminium and copper electrodes. This study focuses on the peat water treatment using electrocoagulation system. The fabricated electrocoagulation system is designed according to the characteristics in which the technology for building and the material used for constructing the electrocoagulation system should be available locally, the electrocoagulation system should be easy to fabricate and maintain, as well as low cost for construction and operation. For this study, Response Surface Methodology in Minitab software and Microsoft Excel are used for kinetic studies, statistical modelling, and process optimization. Process optimization is carried out to minimize energy consumption as well as the turbidity and TSS level. The optimum conditions for batch and continuous electrocoagulation system are 14.899 A/m2 and 41.818 min, and 3.861 A/m2 and 37.778 min respectively.


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