scholarly journals The Impact of Temporary Means of Access on Buildings Envelope’s Maintenance Costs

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 601
Author(s):  
Cláudia Ferreira ◽  
Ilídio S. Dias ◽  
Ana Silva ◽  
Jorge de Brito ◽  
Inês Flores-Colen

Accessibility to buildings’ envelope depends on efficient inspection and other maintenance actions of their components. When access to these components is not planned, special means of access are required to carry out the maintenance work. Means of access, besides having a fundamental role on the quality of maintenance works of building envelope components, also represents a considerable part of the maintenance costs. Thus, to optimize costs and resources in maintenance plans, assessment of the impact of the means of access on maintenance costs is crucial. For works in height, there are several alternative means of access. The choice of the most adequate solution is strongly linked to the characteristics (e.g., architecture, height) and constraints (e.g., users, surrounding space) of each building, the maintenance needs of the envelope, and the time and funds available for the intervention. Therefore, in this study, a sensitivity analysis to understand how the cost of means of access can influence the maintenance costs is carried out. Moreover, the optimisation of maintenance activities in façade claddings is also analysed. This study intends to assess whether it is advantageous to consider permanent means of access during the design phase or opt for temporary means of access. In a first stage, the impact of six temporary means of access (supported and suspended scaffolds; articulated booms; telescopic booms; scissor lifts; and rope access) on the maintenance plans developed for the six types of claddings (ceramic tiling systems—CTS, natural stone claddings—NSC, rendered façades—RF, painted surfaces—PS, external thermal insulation composite systems—ETICS, and architectural concrete façades—ACF) is examined. The impact is estimated through a stochastic maintenance model based on Petri nets. After that, a sensitivity analysis and a multi-criteria decision analysis are performed. Based on the results, general recommendations are presented concerning the maintenance strategies to adopt in the cladding solutions analysed. The results reveal that planning the means of access during the design stage can be economically beneficial for all buildings’ envelope components.

2019 ◽  
Vol 70 (1) ◽  
pp. 26-29 ◽  
Author(s):  
Tinevimbo Shiri ◽  
Angela Loyse ◽  
Lawrence Mwenge ◽  
Tao Chen ◽  
Shabir Lakhi ◽  
...  

Abstract Background Mortality from cryptococcal meningitis remains very high in Africa. In the Advancing Cryptococcal Meningitis Treatment for Africa (ACTA) trial, 2 weeks of fluconazole (FLU) plus flucytosine (5FC) was as effective and less costly than 2 weeks of amphotericin-based regimens. However, many African settings treat with FLU monotherapy, and the cost-effectiveness of adding 5FC to FLU is uncertain. Methods The effectiveness and costs of FLU+5FC were taken from ACTA, which included a costing analysis at the Zambian site. The effectiveness of FLU was derived from cohorts of consecutively enrolled patients, managed in respects other than drug therapy, as were participants in ACTA. FLU costs were derived from costs of FLU+5FC in ACTA, by subtracting 5FC drug and monitoring costs. The cost-effectiveness of FLU+5FC vs FLU alone was measured as the incremental cost-effectiveness ratio (ICER). A probabilistic sensitivity analysis assessed uncertainties and a bivariate deterministic sensitivity analysis examined the impact of varying mortality and 5FC drug costs on the ICER. Results The mean costs per patient were US $847 (95% confidence interval [CI] $776–927) for FLU+5FC, and US $628 (95% CI $557–709) for FLU. The 10-week mortality rate was 35.1% (95% CI 28.9–41.7%) with FLU+5FC and 53.8% (95% CI 43.1–64.1%) with FLU. At the current 5FC price of US $1.30 per 500 mg tablet, the ICER of 5FC+FLU versus FLU alone was US $65 (95% CI $28–208) per life-year saved. Reducing the 5FC cost to between US $0.80 and US $0.40 per 500 mg resulted in an ICER between US $44 and US $28 per life-year saved. Conclusions The addition of 5FC to FLU is cost-effective for cryptococcal meningitis treatment in Africa and, if made available widely, could substantially reduce mortality rates among human immunodeficiency virus–infected persons in Africa.


2021 ◽  
Vol 13 (6) ◽  
pp. 3054
Author(s):  
Renata Tubelo ◽  
Lucelia Rodrigues ◽  
Mark Gillott ◽  
May Zune

In Brazil, the delivery of homes for low-inc ome households is dictated by costs rather than performance. Issues such as the impact of climate change, affordability of operational energy use, and lack of energy security are not taken into account, even though they can severely impact the occupants. In this work, the authors evaluated the thermal performance of two affordable houses as-built and after the integration of envelope improvements. A new replicable method to evaluate the cost-effectiveness of these improvements was proposed. The case study houses comprise the most common affordable housing type delivered widely across Brazil and a proposition of a better affordable housing solution, built in Porto Alegre, southern Brazil, integrating passive design strategies to increase thermal comfort. The findings reveal a potential for improving indoor thermal conditions by up to 76% and 73%, respectively, if costs are not a concern, and 40% and 45% with a cost increase of 12% and 9% if a comfort criterion of 20–25 °C was considered. Equations to estimate costs of improvements in affordable housing were developed. The authors concluded that there is a great scope for building envelope optimisation, and that this is still possible without significant impact on budget.


2020 ◽  
Vol 310 ◽  
pp. 00046
Author(s):  
Lenka Kabošová ◽  
Eva Kormaníková ◽  
Stanislav Kmeť ◽  
Dušan Katunský

Building skins are persistently exposed to changes in the weather, including the cases of weather extremes, increasing in frequency due to global climate change. As a consequence of the advancements of digital design tools, the integration of the weather conditions into the design process is much smoother. The impact of the ambient conditions on buildings and their structures can be digitally analyzed as early as in the conceptual design stage. These new design tools stimulate original ideas for shape-changing building skins, actively reacting to the dynamic weather conditions. In the paper, a digital design method is introduced, leading towards the design of a building skin, able of the passive shape adaptation when subjected to the wind. The designed building skin consists of a tensegrity structure where the tensioned elements are substituted by a tensile membrane, creating a self-equilibrated building skin element. In the previous research, a small prototype of this wind-adaptive element was created. The computer simulations are employed to predict the adaptive behavior of a bigger, full-scale building skin element. The before-mentioned building envelope becomes an active player in its surrounding environment, passively reacting to the wind in real-time, thanks to the geometric and material properties. Due to the local shape changes caused by the wind force, the wind can be perceived unconventionally through the adaptive building structure.


BMJ Open ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. e035224
Author(s):  
Haoya Yun ◽  
Guoqiang Zhao ◽  
Xiaojie Sun ◽  
Lizheng Shi

ObjectiveThis study aimed to estimate the cost–utility of sofosbuvir/velpatasvir (SOF/VEL) compared with other direct-acting antivirals (DAAs) in Chinese patients with hepatitis C virus (HCV).DesignA Markov model was developed to estimate the disease progression of patients with HCV over a lifetime horizon from the healthcare system perspective. Efficacy, clinical inputs and utilities were derived from the published literature. Drug costs were from the market price survey, and health costs for Markov health states were sourced from a Chinese study. Costs and utilities were discounted at an annual rate of 5%. One-way and probabilistic sensitivity analyses were conducted to test the impact of input parameters on the results.InterventionsSOF/VEL was compared with sofosbuvir+ribavirin (SR), sofosbuvir+dasabuvir (SD), daclatasvir+asunaprevir (DCV/ASV), ombitasvir/paritaprevir/ritonavir+dasabuvir (3D) and elbasvir/grazoprevir (EBR/GZR).Primary and secondary outcomesCosts, quality-adjusted life years (QALYs) and incremental cost–utility ratios (ICURs).ResultsSOF/VEL was economically dominant over SR and SD. However, 3D was economically dominant compared with SOF/VEL. Compared with DCV/ASV, SOF/VEL was cost-effective with the ICUR of US$1522 per QALY. Compared with EBR/GZR, it was not cost-effective with the ICUR of US$369 627 per QALY. One-way sensitivity analysis demonstrated that reducing the cost of SOF/VEL to the lower value of CI resulted in dominance over EBR/GZR and 3D. Probabilistic sensitivity analysis demonstrated that 3D was cost-effective in 100% of iterations in patients with genotype (GT) 1b and SOF/VEL was not cost-effective.ConclusionsCompared with other oral DAA agents, SOF/VEL treatment was not the most cost-effectiveness option for patients with chronic HCV GT1b in China. Lower the price of SOF/VEL will make it cost-effective while simplifying treatment and achieving the goal of HCV elimination.


2020 ◽  
Vol 11 ◽  
Author(s):  
Ruxu You ◽  
Zijie Liu

Objective: Prevalence of osteoporosis in Chinese postmenopausal women has significantly increased over the past decade and oral bisphosphonates are the most potent antiresorptive drugs. The purpose of the present research was to evaluate the cost-effectiveness of oral alendronate for individuals with osteoporosis. We also assessed the impact of medication compliance and persistence on economic outcomes of alendronate and potential economic evaluations of persistence-enhancing interventions.Methods: We constructed an individual-level state-transition model to project health outcomes and costs of oral alendronate for Chinese postmenopausal osteoporotic women. The impact of medication compliance and persistence on economic evaluation was addressed in various scenario analyses. Model inputs were derived from clinical trials and published sources, where available. Deterministic and probabilistic sensitivity analyses were conducted to explore the impact of uncertainties and assumptions on the cost-effectiveness results.Results: Compared with no treatment, alendronate treatment was associated with an additional 0.052 QALYs (quality-adjusted life-years) at an additional cost of USD 738, which yielded an incremental cost-effectiveness ratio (ICER) of USD 14,192.308/QALY. The ICER for the different scenarios (full compliance, full persistence, and both full persistence and full compliance) was USD 4,933.333/QALY, USD 3,006.849/QALY, and USD 2,049.822/QALY, respectively. One-way sensitivity analysis showed the ICER was most sensitive to variations in time horizon and residual effect. Probabilistic sensitivity analysis demonstrated that, at a willingness to pay of USD 29,340/QALY, the probability that oral alendronate therapy will be cost-effective is approximately 80%.Conclusion: The findings support the view that oral alendronate is cost-effective for the treatment of osteoporotic fractures in Chinese postmenopausal women. Medication persistence is found to have a greater impact on cost-effectiveness than compliance and interventions to improve persistence to be an efficient use of resources.


1989 ◽  
Vol 16 (1) ◽  
pp. 55-61
Author(s):  
Radu Zmeureanu ◽  
Paul Fazio

Closer collaboration of the traditional disciplines of architecture, structural engineering, and mechanical engineering is required at the design stage to better deal with the complexity of modern buildings, and to maintain the cost of energy low while providing a suitable indoor environment during the life of the building.The availability of personal computers and the development of interactive software provide more opportunities for an integrated approach to building design. This approach is useful in determining the impact of one subsystem on the performance of another subsystem and on the overall performance of the building. An example of such an integrated approach is presented in this paper, which determines the impact of a structural system (hollow core slab) and its mass on the energy consumption of the building. Key words: building design, computers, energy.


2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Yu Liu ◽  
Xiaolei Yin ◽  
Paul Arendt ◽  
Wei Chen ◽  
Hong-Zhong Huang

Statistical sensitivity analysis (SSA) is an effective methodology to examine the impact of variations in model inputs on the variations in model outputs at either a prior or posterior design stage. A hierarchical statistical sensitivity analysis (HSSA) method has been proposed in literature to incorporate SSA in designing complex engineering systems with a hierarchical structure. However, the original HSSA method only deals with hierarchical systems with independent subsystems. For engineering systems with dependent subsystem responses and shared variables, an extended HSSA method with shared variables (named HSSA-SV) is developed in this work. A top-down strategy, the same as in the original HSSA method, is employed to direct SSA from the top level to lower levels. To overcome the limitation of the original HSSA method, the concept of a subset SSA is utilized to group a set of dependent responses from the lower level submodels in the upper level SSA and the covariance of dependent responses is decomposed into the contributions from individual shared variables. An extended aggregation formulation is developed to integrate local submodel SSA results to estimate the global impact of lower level inputs on the top level response. The effectiveness of the proposed HSSA-SV method is illustrated via a mathematical example and a multiscale design problem.


Author(s):  
Regina Dias Ferreira ◽  
Beda Barkokebas ◽  
Lana Secchi ◽  
Mustafa Gul ◽  
YuXiang Chen ◽  
...  

In countries with cold climates such as Canada, the cost of providing space heating during the construction phase, also known as temporary heating, results in a significant additional construction cost, which causes budget deviations thus affecting the projectäó»s financial performance. In fact, the estimation of temporary heating is commonly overlooked due to the uncertainties such as weather forecast and the projectäó»s actual onsite schedule. The cost of temporary heating comprises two parts: (1) the cost of equipment rental, and (2) the fuel consumption required to heat a given area when the temperature falls below a certain threshold. The fuel consumption of the equipment is related to the temperature and exposure of the buildingäó»s envelope to the current weather conditions. Thus, the construction of the building envelope is critical to the reduction of fuel consumption and the consequent temporary heating cost of the project. In this context, the research presented in this paper aims to estimate the impacts of temporary heating for various constructive methods, such as the traditional stick-built practice and a few variations of panelized construction (in regard to the insulation used), by developing a simulation model to observe the variation of weather data, construction schedule, and fuel consumption for each scenario. To perform this analysis, a 4-story residential building located in the city of Edmonton, Alberta, Canada, is used as a case study in which the proposed scenarios are compared in order to address the advantages of industrialized components in reducing the cost of temporary heating.


2020 ◽  
Vol 10 ◽  
Author(s):  
Jiangping Yang ◽  
Jiaqi Han ◽  
Jinlan He ◽  
Baofeng Duan ◽  
Qiheng Gou ◽  
...  

BackgroundAddition of gemcitabine and cisplatin (GP) or docetaxel and cisplatin plus fluorouracil (TPF) to concurrent chemoradiotherapy (CCRT) significantly improved survival in locoregionally advanced nasopharyngeal carcinoma (NPC). However, an economic evaluation of these regimens remains unknown. The purpose of this study is to compare the cost-effectiveness of GP versus TPF regimen in the treatment of locoregionally advanced NPC in China.Materials and methodsA comprehensive Markov model was developed to evaluate the health and economic outcomes of GP versus TPF regimen for patients with locoregionally advanced NPC. Baseline and clinical outcome were derived from 158 patients with newly diagnosed stage III-IVA NPC between 2010 and 2015. We evaluated the quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs) from the perspective of the Chinese healthcare system. One-way sensitive analysis explored the impact of uncertainty in key model parameters on results, and probabilistic uncertainty was assessed through a Monte Carlo probabilistic sensitivity analysis.ResultsGP regimen provided an additional 0.42 QALYs with incremental cost of $3,821.99, resulting in an ICER of $9,099.98 per QALY versus TPF regimen at the real-world setting. One-way sensitivity analysis found that the results were most sensitive to the cost and proportion of receiving subsequent treatment in two groups. The probability that GP regimen being cost-effective compared with TPF regimen was 86.9% at a willingness-to-pay (WTP) of $31,008.16 per QALY.ConclusionUsing real-world data, GP regimen was demonstrated a cost-effective alternative to TFP regimen for patients with locoregionally advanced NPC in China. It provides valuable evidence for clinicians when making treatment decisions to improve the cost-effectiveness of treatment.


Author(s):  
Serhii Kononchuk ◽  
◽  
Oleksandr Skrypnyk ◽  
Volodymyr Sviatskyi ◽  
Viktor Pukalov ◽  
...  

The most common technology for the manufacture of metal parts and work pieces is casting. High-tech branches of mechanical engineering require the production of high-quality castings of complex configuration from modern alloys with a given chemical composition and mechanical properties. The analysis of the causes of slag inclusions and ways to prevent them showed that in addition to technological means related to quality preparation of metal before pouring, a significant role is played by quiet continuous pouring of metal and properly designed foundry system, including slag trap. However, the use of the most common foundry systems (braking, throttle, with centrifugal slag traps, rain, siphon) to increase the efficiency of slag retention is associated with increased metal consumption, and as a consequence, leads to an increase in the cost of casting. Conducting experimental research by varying the design of the slag trap leads to an increase in the number of field experiments, given their complexity, limited by great difficulties. On the other hand, computer flow modeling allows to study the influence of slag trap design on the flow rate of the melt at the design stage and significantly reduce the cost of introduction of new castings. In order to reliably capture slag and reduce the speed of movement of the melt in the foundries, which provides a smooth filling of the form with an alloy, but without additional costs of metal, the original design of the ribbed slag catcher is proposed. The results of parametric modeling of the melt flow in the channel of the ribbed slag trap showed a decrease in the flow rate along the cross-sectional height of the slag trap compared to traditional by 0.028 m / s or 14.5%. This allowed to reduce the length of the slag trap to the first feeder. The expected metal savings are 0.26%. The form made using a 3D model of the slag trap showed satisfactory molding ability. But the obtained research results are of a recommendatory nature and require practical verification in the production environment. In addition, by varying parameters such as the height of the ribs, the distance between them, the angle of inclination, we can obtain similar results for different castings of different alloys. Given all this, there is a need for further study of the impact of the design of the slag trap on the efficiency of slag retention.


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