scholarly journals The investigation of the effect of atmospheric conditions on the tempreture drop across heat treatment systems

2021 ◽  
Author(s):  
◽  
Velaphi Absolom Phoswa
Keyword(s):  
Heat Treatment ◽  
Numerical Analysis ◽  
Cost Analysis ◽  
Heat Loss ◽  
Heat Energy ◽  
Energy Losses ◽  
Atmospheric Conditions ◽  
Excel Spreadsheet ◽  
Steam Pipeline ◽  
The Cost

The purpose of the present study is to investigate the effect of atmospheric conditions on the temperature drop across heat treatment systems (piping and vessels). Due to the economy and power energy consumption, it has become necessary for Isegen SA (Pty) Ltd to conduct a numerical analysis on heat transfer since they are unable to predict and quantify heat energy losses in the steam reticulation systems. These losses occur due to the fact that there is no proper methodology to effectively predict heat energy losses in heating processes. When a steam pipeline is at a higher temperature than the air surrounding it, heat will pass through the wall of the pipeline from the steam to the surrounding air. This heat loss may cause the temperature of the steam to fall and the boiler efficiency decreases because the boiler requires more gas to maintain the plant steam required. Steam savings are very vital for Isegen SA (Pty) Ltd as most of the heating systems that they utilize are a direct steam injection. This means a large quantity of the sensible heat energy of the steam distributed into the factory is not recovered. Therefore, a numerical analysis was developed in order to investigate heat energy losses and steam consumption, while flowing through the insulated steam pipeline depending on the ambient and operational temperatures. The study proved that there is a heat energy loss as well as a temperature loss during the steam transportation through the insulated steam pipeline after conducting the numerical analysis. The thickness conduction resistance was obtained for thermal insulation complying with the required standards. The methodology involved the use of application of Excel spreadsheet to develop a theoretical model of the problem. The obtained model allowed us to get the required solution of the problem and calculate the heat loss for different thicknesses of the pipe’s insulation. The application of Excel spreadsheet steady state thermal method was used for obtaining the value of heat loss of steam at a critical thickness of insulation. After conducting the cost analysis, it has been found that Isegen SA (Pty) Ltd could save between one to two million Rands per year in fuel. The cost analysis conducted is based on the steam cost and heat energy losses. This study showed that steam waste is costly in both an environmental and financial sense. Therefore, this required prompt attention in order to ensure that the steam system is working at its optimum efficiency with minimal impact on the environment. This study was acknowledged by the Isegen SA (Pty) Ltd management, and a new technological process is to be implemented (see Appendix R for the relevant documents).

Identyfikacja kosztów pogorszenia reputacji przedsiębiorstwa z perspektywy interesariuszy

2014 ◽  
pp. 10-15
Author(s):  
Danuta Szwajca ◽  
Alina Rydzewska ◽  
Tomasz Nawrocki
Keyword(s):  
Cost Analysis ◽  
Economic Costs ◽  
Crisis Situation ◽  
Modern Economy ◽  
The Cost ◽  
A Company ◽  
Crisis Situations

In the realities of modern economy even the best-managed company is not able to avoid threats and bad decisions, that can cause a crisis. Each crisis situation, that a company experiences, generates not only measurable economic costs, but also more difficult to assess and measure costs of a deteriorated reputation. These costs are the result of infringement of interests or failing to satisfy different stakeholders expectations. The aim of this article is an attempt to identify the cost of reputation deterioration in the context of the various interests of stakeholders groups. In the first part, the paper presents the effects of good and bad reputation, the reputation "contamination" path in a crisis situation and a cost analysis caused by it. The second part is empirical, where the identification of crisis situations measurable costs and reputation deterioration based on the examples of three selected companies was performed.

COMPUTER MODELING OF THE STRUCTURE OF FOREST DRYING CHAMBERS, REDUCING HEAT LOSS

2020 ◽  
Vol 2020 (4) ◽  
pp. 60-67
Author(s):  
Boris Pruss ◽  
Viktor Romanov ◽  
Yaroslav Prozorov ◽  
Olga Pleskacheva
Keyword(s):  
Computer Modeling ◽  
Heat Loss ◽  
Heat Losses ◽  
Heat Energy ◽  
Insulating Materials ◽  
Sawn Timber ◽  
Drying Chamber

The paper presents the theory of calculating heat loss through the fences of timber drying chambers. The software for computer modeling of the process of transferring heat energy through the fences of the drying chamber, consisting of various heat-insulating materials, for calculating heat losses during drying of sawn timber is described. The efficiency of the use of modern heat-insulating materials to reduce heat losses during drying of sawn timber has been experimentally confirmed.

Economic impact of the use of the National Surgical Quality Improvement Program

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Alvine Fansi ◽  
Angela Ly ◽  
Julie Mayrand ◽  
Maggy Wassef ◽  
Aldanie Rho ◽  
...  
Keyword(s):  
Quality Improvement ◽  
Cost Analysis ◽  
Economic Impact ◽  
Quality Improvement Program ◽  
Economic Evaluations ◽  
Complication Rates ◽  
Improvement Program ◽  
Surgical Quality ◽  
Acs Nsqip ◽  
The Cost

Objectives The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP®) is a validated, risk-adjusted database for improving the quality and security of surgical care. ACS NSQIP can help participating hospitals target areas that need improvement. The aim of this study was to systematically review the literature analyzing the economic impact of using NSQIP. This paper also provides an estimation of annual cost savings following the implementation of NSQIP and quality improvement (QI) activities in two hospitals in Quebec. Methods In June 2018, we searched in seven databases, including PubMed, Embase, and NHSEED for economic evaluations based on NSQIP data. Contextual NSQIP databases from two hospitals were collected and analyzed. A cost analysis was conducted from the hospital care perspective, comparing complication costs before and after 1 year of the implementation of NSQIP and QI activities. The number and the cost of complications are measured. Costs are presented in 2018 Canadian dollars. Results Out of 1,612 studies, 11 were selected. The level of overall evidence was judged to be of moderate to high quality. In general, data showed that, following the implementation of NSQIP and QI activities, a significant decrease in complications and associated costs was observed, which improved with time. In the cost analysis of contextual data, the reduction in complication costs outweighed the cost of implementing NSQIP. However, this cost analysis did not take into account the costs of QI activities. Conclusions NSQIP improves complication rates and associated costs when QI activities are implemented.

scholarly journals A cost analysis to address issues of budget constraints on the implementation of the indoor residual spray programme in two districts of Maputo Province, Mozambique

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Neide Canana
Keyword(s):  
Sensitivity Analysis ◽  
Cost Analysis ◽  
Financial Analysis ◽  
Indoor Residual Spraying ◽  
Economic Cost ◽  
Cost Information ◽  
Financial Cost ◽  
Provider Perspective ◽  
The Government ◽  
The Cost

Abstract Background It is frequently said that funding is essential to ensure optimal results from a malaria intervention control. However, in recent years, the capacity of the government of Mozambique to sustain the operational cost of indoor residual spraying (IRS) is facing numerous challenges due to restrictions of the Official Development Assistance. The purpose of the study was to estimate the cost of IRS operationalization in two districts of Maputo Province (Matutuíne and Namaacha) in Mozambique. The evidence produced in this study intends to provide decision-makers with insight into where they need to pay close attention in future planning in order to operationalize IRS with the existent budget in the actual context of budget restrictions. Methods Cost information was collected retrospectively from the provider perspective, and both economic and financial costs were calculated. A “one-way” deterministic sensitivity analysis was performed. Results The average economic costs totaled US$117,351.34, with an average economic cost per household sprayed of US$16.35, and an average economic cost per person protected of US$4.09. The average financial cost totaled US$69,174.83, with an average financial cost per household sprayed and per person protected of US$9.84 and US$2.46, respectively. Vehicle, salary, and insecticide costs were the greatest contributors to overall cost in the economic and financial analysis, corresponding to 52%, 17%, and 13% in the economic analysis and 21%, 27%, and 22% in the financial analysis, respectively. The sensitivity analysis was adapted to a range of ± (above and under) 25% change. There was an approximate change of 14% in the average economic cost when vehicle costs were decreased by 25%. In the financial analysis, the average financial cost was lowered by 7% when salary costs were decreased by 25%. Conclusions Altogether, the current cost analysis provides an impetus for the consideration of targeted IRS operationalization within the available governmental budget, by using locally-available human resources as spray operators to decrease costs and having IRS rounds be correctly timed to coincide with the build-up of vector populations.

scholarly journals The influence of air movement and atmospheric conditions on the heat loss from a cylindrical moist body

1939 ◽  
Vol 39 (1) ◽  
pp. 60-89 ◽  
Author(s):  
Alan J. Canny ◽  
C. J. Martin
Keyword(s):  
Heat Exchange ◽  
Heat Loss ◽  
Wind Velocity ◽  
Effective Temperature ◽  
Physical System ◽  
Square Root ◽  
Atmospheric Conditions ◽  
Internal Temperature ◽  
Air Movement ◽  
Internal Conductivity

It is emphasized that as heat exchange is controlled by the temperature of that boundary layer of molecular dimensions which separates a cooling body from its environment and from which evaporation occurs, attempts to relate heat loss with internal temperature have resulted only in empirical formulae. A rational formula involving the temperature of the evaporating surface is suggested, and it is shown how in the case of a system of sufficient simplicity all the terms can be either measured or derived from experiments.The results of experiments with a small moistened cylinder are detailed illustrating the effect of wind velocity upon evaporative and convective heat loss under the one condition when the evaporating surface remains at constant temperature notwithstanding variations in wind, namely, when the whole system has been cooled to wet-bulb temperature. Evaporative loss is found to vary as V0.65, convective as V0.70.Experiments are next described showing the effect of wind upon evaporative and convective losses when, the internal temperature being constant, the temperature of the evaporating surface fluctuates in consequence of varying wind velocity. Heat loss now varies very closely as V0.5 at velocities greater than 1 m./sec. At velocities below 1 m./sec. the same relation of heat loss to velocity obtains if due allowance be made for natural convection. This square root function is fortuitous, and heat loss varied between the square root and cube root of the velocity as the internal conductivity was diminished.Attention is drawn to the impossibility of forming general conclusions from observations on any particular system, as the way in which the rate of heat loss varies with the velocity of the wind depends not only upon the internal conductivity of the system but also on its size and shape.Observations are described showing the influence of varying the internal temperature on total and evaporative heat loss with constant wind velocity and constant atmospheric conditions. These experiments furnish data from which the surface temperature can be derived from measurements of evaporation, and show that the temperature of the surface and the rate of loss of heat by convection are both linear functions of the internal temperature at any one wind velocity. They also show that the values of the constants of the system derived from experiments at the temperature of the wet bulb are applicable when the cylinder is heated.An analysis of the results of the experiments with varying internal temperature indicates that the temperature of the evaporating surface (ts) is related to the internal temperature (t1) and that of the wet bulb (tw) by the expression The value of C with varying wind velocity is ascertained by experiments, thus affording another means of arriving at the temperature of the evaporating layer. Values of ts obtained in this way are compared with those determined by observing the rate of evaporation and show reasonable agreement.It is shown how, knowing the temperature of the evaporating layer, the constants of the system employed and the effect of velocity of wind upon heat exchange, the rate of loss of heat by evaporation and by convection under given conditions can be predicted. Instances of the agreement between predicted and observed values are given.From the formula representing the influence of atmospheric conditions on heat loss it can be shown, by calculation, that if the wet-bulb temperature remains constant considerable variations in the temperature of the dry-bulb influence but slightly the heat loss from the moist cylinder.It will be seen that the analysis of the effects of environmental changes on the heat loss from a simple physical system such as was used presents no serious difficulties. Such an analysis, unfortunately, does not enable deductions to be made with reference to systems of different physical characteristics. How observations on such systems can be related in other than a qualitative manner to the effects of corresponding changes on living creature differing in size and shape and degree of moistening of their surfaces is not clear. When account is taken of the ability of living beings to alter the vascularity of their surface tissues and so to vary the temperature of the body surface while other factors remain constant, the difficulties in relating the cooling of any physical system to the loss of heat from animals become painfully apparent.The most hopeful method of assessing the effect of air movement and atmospheric conditions on the heat loss from the human body seems to be in terms of a subjectively determined standard such as the effective temperature scale of Houghton & Yaglou. The validity of such a scale has received support from observations by Houghton et al. (1924) and Vernon & Warner (1932) on the relation of pulse rate, body temperature, metabolism and other physiological variables to “effective temperature”.

The cost of depression – A cost analysis from a large database

2013 ◽  
Vol 147 (1-3) ◽  
pp. 137-143 ◽  
Author(s):  
Katja Kleine-Budde ◽  
Romina Müller ◽  
Wolfram Kawohl ◽  
Anke Bramesfeld ◽  
Jörn Moock ◽  
...  
Keyword(s):  
Cost Analysis ◽  
Large Database ◽  
The Cost

scholarly journals Cost Analysis of Methylprednisolone Treatment of Multiple Sclerosis Patients

1998 ◽  
Vol 25 (3) ◽  
pp. 222-229 ◽  
Author(s):  
Lynda S. Robson ◽  
Charlene Bain ◽  
Shann Beck ◽  
Suzanne Guthrie ◽  
Peter C. Coyte ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Cost Saving ◽  
Cost Analysis ◽  
Home Care ◽  
Care Program ◽  
Sensitivity Analyses ◽  
Patient Treatment ◽  
Fiscal Year ◽  
Multiple Sclerosis Patients ◽  
The Cost

ABSTRACT:Background:Intravenous methylprednisolone (IVMP) is the treatment of choice for multiple sclerosis (MS) patients undergoing acute exacerbation of disease symptoms and yet its cost has not been accurately determined. Determination of this cost in different settings is also pertinent to consideration of cost-saving alternatives to in-patient treatment.Methods:Cost analysis from the point of view of the health care system of IVMP treatment of MS patients receiving treatment in association with a selected Toronto teaching hospital in fiscal year 1994/95 was carried out. Costs of any concurrent treatments were excluded.Results:Total cost for 92 patients, based on a 4 dose regime, was estimated to be $78,527. The the cost per patient was $1,1181.84 for in-patients (IP), $714.64 for out-patients of the MS Clinic (OP) and $774.21 for patients whose treatment was initiated in the Clinic, but completed in the home (HC). Sensitivity analyses indicated: 1) IP treatment was in all cases more expensive than that of OP or HC; 2) the cost savings of OP vs. HC was sensitive to assumptions made regarding Clinic overhead, Clinic nursing costs and Home Care Program overhead.Conclusion:Alternatives to in-patient care must be considered carefully. In this study, both out-patient and in-home treatment were cost-saving alternatives to in-patient treatment, but large differences in the cost of hospital out-patient vs. in-home care could not be demonstrated.

scholarly journals DC-link sensorless control strategy for grid-connected PV systems

2021 ◽  
Author(s):  
Mostafa Ahmed ◽  
Mohamed Abdelrahem ◽  
Ahmed Farhan ◽  
Ibrahim Harbi ◽  
Ralph Kennel
Keyword(s):  
Sensorless Control ◽  
Current Loop ◽  
Sensor Failure ◽  
Atmospheric Conditions ◽  
Step Size ◽  
Pv System ◽  
Control Approach ◽  
Control Loops ◽  
Pv Systems ◽  
The Cost

AbstractSensorless strategies become very popular in modern control techniques because they increase the system reliability. Besides, they can be used as back-up control in case of sensor failure. In this paper, a DC-link sensorless control approach is developed, which is suited for grid-connected PV systems. The studied system is a two-stage PV scheme, where the DC–DC stage (boost converter) is controlled using an adaptive step-size perturb and observe (P&O) method. Further, the inverter control is accomplished by voltage oriented control (VOC). Generally, the VOC is implemented with two cascaded control loops, namely an outer voltage loop and an inner current loop. However, in this work, the outer loop is avoided and the reference current is generated using a losses model for the system. The losses model accounts for the most significant losses in the PV system. Moreover, particle swarm optimization (PSO) is utilized to compensate for the unmodeled losses. The PSO is executed offline for the purpose of calculation burden reduction. The proposed approach simplifies the cascaded VOC strategy and eliminates the DC-link voltage sensor, which in turn decreases the cost of the system. Finally, the proposed technique is compared with the conventional one at different atmospheric conditions and validated using MATLAB simulation results.

scholarly journals Procedure for detecting tobamovirus in tomato and pepper seeds decreases the cost analysis

Bragantia ◽  
2018 ◽  
Vol 77 (4) ◽  
pp. 590-598
Author(s):  
João Eduardo Melo Almeida ◽  
Antonia dos Reis Figueira ◽  
Priscilla de Sousa Geraldino Duarte ◽  
Mauricio Antônio Lucas ◽  
Nara Edreira Alencar
Keyword(s):  
Cost Analysis ◽  
The Cost

scholarly journals The Effect of Heat Treatment on the Microstructure and Mechanical Properties of the Novel Low-Cost Ti-3Al-5Mo-4Cr-2Zr-1Fe Alloy

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3798
Author(s):  
Meng Sun ◽  
Dong Li ◽  
Yanhua Guo ◽  
Ying Wang ◽  
Yuecheng Dong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aging Time ◽  
Volume Fraction ◽  
Low Cost ◽  
Solution Treatment ◽  
Solution Temperature ◽  
The Novel ◽  
Α Phase ◽  
The Cost

In order to reduce the cost of titanium alloys, a novel low-cost Ti-3Al-5Mo-4Cr-2Zr-1Fe (Ti-35421) titanium alloy was developed. The influence of heat treatment on the microstructure characteristics and mechanical properties of the new alloy was investigated. The results showed that the microstructure of Ti-35421 alloy consists of a lamina primary α phase and a β phase after the solution treatment at the α + β region. After aging treatment, the secondary α phase precipitates in the β matrix. The precipitation of the secondary α phase is closely related to heat treatment parameters—the volume fraction and size of the secondary α phase increase when increasing the solution temperature or aging time. At the same solution temperature and aging time, the secondary α phase became coarser, and the fraction decreased with increasing aging temperature. When Ti-35421 alloy was solution-treated at the α + β region for 1 h with aging surpassing 8 h, the tensile strength, yield strength, elongation and reduction of the area were achieved in a range of 1172.7–1459.0 MPa, 1135.1–1355.5 MPa, 5.2–11.8%, and 7.5–32.5%, respectively. The novel low-cost Ti-35421 alloy maintains mechanical properties and reduces the cost of materials compared with Ti-3Al-5Mo-5V-4Cr-2Zr (Ti-B19) alloy.

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