scholarly journals Impact of Environmental Exposure Conditions on the Maintenance of Facades’ Claddings

Buildings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 138
Author(s):  
Cláudia Ferreira ◽  
Joana Barrelas ◽  
Ana Silva ◽  
Jorge de Brito ◽  
Ilídio S. Dias ◽  
...  
Keyword(s):  
Environmental Exposure ◽  
Degradation Process ◽  
Building Envelope ◽  
Decision Makers ◽  
Exposure Condition ◽  
Environmental Actions ◽  
Tiling Systems ◽  
Building Components ◽  
Maintenance Requirements ◽  
Over Time

Façades, as the most external building envelope component, are subject to different ex-ternal environmental loads, such as: Temperature, precipitation, damp, and wind. Therefore, the contribution of environmental actions to the occurrence of defects in façades claddings is an important subject of study since these actions strongly affect the degradation process and natural ageing of these components during their service life. In this study, a methodology to support decision-makers in the process of selecting a façade cladding system and the maintenance strategy to implement is presented and discussed. This methodology covers the performance of four façade claddings (ceramic tiling systems (CTS), natural stone claddings (NSC), external thermal insulation composite systems (ETICS), and architectural concrete façades (ACF)) over time, according to three environmental exposure variables (exposure to damp, distance from the sea, and orientation). The databases were established based on the diagnosis of the degradation condition of these claddings in-service conditions, in Portugal. The results reveal that the environmental exposure variables have a significant impact on maintenance requirements and costs. For all the categories of the environmental exposure condition variables, under all scenarios, ETICS is the least favorable constructive solution while CTS is the most advantageous solution. Furthermore, the results show that properly implemented maintenance activities enhance the performance level of building components, which positively affects their degradation behavior over time.

scholarly journals Impact of Environmental Exposure on the Service Life of Façade Claddings—A Statistical Analysis

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 615
Author(s):  
Joana Barrelas ◽  
Ilídio S. Dias ◽  
Ana Silva ◽  
Jorge de Brito ◽  
Inês Flores-Colen ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Service Life ◽  
Environmental Exposure ◽  
Degradation Process ◽  
Related Factors ◽  
High Exposure ◽  
Tiling System ◽  
Building Components ◽  
The Impact ◽  
Exposure Conditions

Façade claddings, as the outer protection layer of the building’s envelope, are directly exposed to environmental degradation agents. The façades’ orientation and their distance from the sea, among other location and protection-related factors, influence their vulnerability to climate loads, in particular wind and air humidity. These loads, as well as exposure to air pollution, affect the degradation process of claddings and the durability of façades. Therefore, studying the impact of the environmental exposure conditions on the service life of different external claddings provides useful information on their performance over time, which can support (i) decision-makers in the selection of the best façade cladding solutions and (ii) further research on the impact of climate change on building components. This study covers six types of cladding: rendered façades (R), natural stone cladding (NSC), ceramic tiling system (CTS), painted surfaces (PS), external thermal insulation composite systems (ETICS), and architectural concrete façades (ACF). Three hundred façades located in Portugal are analysed according to three main groups of variables, which characterize (i) the façades, (ii) their degradation condition, and (iii) the environmental deterioration loads and context. The statistical analysis results reveal that the environmental variables affect the cladding degradation process. South-oriented façades present lower degradation conditions than façades facing north. The distance from the sea and high exposure to pollutants add to the degradation conditions, reducing the expected service life of façades. The results reveal that claddings can be organized according to two main groups: the most durable (CTS, NSC, and ACF) and the least durable (R, PS, and ETICS) systems. This study enables a comprehensive analysis of the data, useful to draw conclusions about the influence of environmental exposure conditions on the degradation and service life of façade claddings.

scholarly journals The efficiency of a dynamically insulated wall in the presence of air leakages

2004 ◽  
Vol 8 (1) ◽  
pp. 83-94
Author(s):  
Angela Kalagasidis-Sasic
Keyword(s):  
System Analysis ◽  
Ventilation System ◽  
Building Envelope ◽  
Leading Role ◽  
Outdoor Climate ◽  
Dynamic Insulation ◽  
Building Components ◽  
Heat And Moisture ◽  
Alternative Designs ◽  
Indoor And Outdoor

The movement of air in and through the building envelope often plays a leading role in the transport of heat and moisture into the building. It is caused by pressure and temperature variations around the building envelope inbuilt ventilation system, occupancy, etc. In order to improve the energy consumption, alternative designs for the ventilation systems are considered. One of them is a dynamically insulated wall as an inlet unit for the supplying air. In order to predict the performance of a dynamically insulated wall, it is necessary to make an analysis of the building as a system. This paper presents such system analysis which takes into account the interaction between the building components and indoor and outdoor climate, both in terms of the air leakage and heat and mass transfer to and from the building components. It is shown that, in the presence of air leakages (unintentional openings) in the enclosure of the building, the efficiency of the dynamic insulation is significantly decreased.

Impact of an Online Birth Control Support Network on Unintended Pregnancy

2015 ◽  
Vol 21 (1) ◽  
pp. 23-36 ◽  
Author(s):  
Jill Antonishak ◽  
Kelleen Kaye ◽  
Lawrence Swiader
Keyword(s):  
Unintended Pregnancy ◽  
Birth Control ◽  
Unprotected Sex ◽  
Support Network ◽  
Control Group ◽  
Exposure Condition ◽  
Exposure Group ◽  
Dose Response Relationship ◽  
Unintended Pregnancies ◽  
Over Time

We evaluated the effects of Bedsider.org—an online birth control support network—on unintended pregnancies among young women aged 18–29. Bedsider is the centerpiece of a comprehensive digital effort to encourage women to use birth control more consistently and effectively and consider using more effective forms of birth control over time. A sample of 2,284 women was randomly assigned to be exposed to Bedsider or to a control group (no exposure) condition. Women were surveyed throughout a 12-month period. Women in the Bedsider exposure group were less likely to have a pregnancy scare, an unintended pregnancy, or unprotected sex compared to the control group. Additionally, women in the Bedsider exposure group were more likely to use a more effective method of contraception over time compared to the control group. Future studies are needed to examine the dose–response relationship for exposure to Bedsider.org and for whom the intervention is most effective.

scholarly journals Modification of the copper wettability by nanosecond laser texturing

2021 ◽  
Vol 2119 (1) ◽  
pp. 012126
Author(s):  
M M Vasilev ◽  
Y G Shukhov ◽  
A A Rodionov ◽  
Y P Li ◽  
M K Lei
Keyword(s):  
Contact Angle ◽  
Laser Treatment ◽  
Environmental Exposure ◽  
Nanosecond Laser ◽  
Laser Texturing ◽  
Copper Surfaces ◽  
Over Time

Abstract Nanosecond laser microstructuring of copper surfaces was performed in this work. The contact angle value immediately after laser treatment decreased sharply and all samples were hydrophilic or superhydrophilic. Hydrophobization of the textured samples occurs as a result of environmental exposure over time. Oxidation and adsorption of carbon and its compounds from the atmosphere leads to a change in the wettability of the irradiated surfaces. The acceleration of hydrophobization process with decrease of fluence was found. It is shown that the stable contact angle, reached after one month, does not depend on the value of the fluence and is about 140°.

Thinking Systemically About Security and Resilience in an Era of Cybered Conflict

2019 ◽  
pp. 44-59
Author(s):  
Peter Dombrowski ◽  
Chris C. Demchak
Keyword(s):  
International System ◽  
Well Being ◽  
Decision Makers ◽  
Systemic Approach ◽  
Economic Systems ◽  
The World ◽  
Peace And War ◽  
Over Time ◽  
Civil Societies

The international system now depends on cyberspace, a global ‘substrate' of massive, complex, insecurely designed networks providing systemic advantages to masses of predators and adversaries. States today face an unprecedented spectrum of ‘cybered conflict' between peace and war with growing existential implications. Their piecemeal searches for defensible jurisdictions are creating a rising Cyber Westphalian world crisscrossed with gateways, holes, national cyber forces, and often partial, uncoordinated, or vague strategies. Over time, the world will have robust, midlevel, and poor cyber powers, with the first tier coercing the others and dominating the rules of exchange. Democratic civil societies are not guaranteed to be robust. For acceptable future societal well-being in a deceptive and opaque cybered world, decision-makers need a systemic approach based on the logic of complex socio-technical-economic systems (STES) to create the systemic resilience and disruption capacities across shareable (across allies/sectors) secure architectures essential to becoming a robust cyber power, which is the focus of this chapter.

Analysis and Decision

2019 ◽  
pp. 161-186
Author(s):  
Jeffrey A. Friedman
Keyword(s):  
Foreign Policy ◽  
Probabilistic Reasoning ◽  
Large Body ◽  
Decision Makers ◽  
Risky Decision ◽  
High Stakes ◽  
Policy Choices ◽  
Foreign Policies ◽  
The U.S ◽  
Over Time

This chapter explains how decision makers can incorporate assessments of uncertainty into high-stakes foreign policy choices. It begins by describing a simple analytic tool called break-even analysis, with which leaders can use explicit probability assessments as a point of leverage for determining whether or not a risky decision is worthwhile. The chapter then explains how transparent probabilistic reasoning is especially important for assessing strategic progress. In some cases, it can actually be impossible to make rigorous judgments about the extent to which foreign policies are making acceptable progress without assessing subjective probabilities in detail. This argument departs from a large body of existing scholarship on learning in international politics that assumes leaders can use a straightforward logic of trial and error to determine how they should update their strategic perceptions over time. The chapter provides examples of these dynamics drawn from the U.S. occupation of Iraq.

scholarly journals On the feasibility of watertight face-sealed window-wall interfaces

2019 ◽  
Vol 282 ◽  
pp. 02015
Author(s):  
Stéphanie Van Linden ◽  
Nathan Van Den Bossche
Keyword(s):  
Laboratory Experiments ◽  
Building Envelope ◽  
Water Infiltration ◽  
Test Results ◽  
Full Scale Test ◽  
Structural Insulated Panels ◽  
Building Components ◽  
Scale Test ◽  
Wood Frame ◽  
Frame Construction

Watertightness is still a major source of concern in the performance of the building envelope. Even very small deficiencies can cause a significant amount of water leakage which may result in structural degradation or malfunctioning of the insulation. The risk of water infiltration is highest at joints between different building components and in particular at the window-wall interface due to the complexity of these joints. This paper focuses on the performance of different solutions to ensure the watertightness of the window-wall interface, e.g. self-adhesive foils, liquid applied coatings, prefabricated frames, self-expanding sealing strips. The performance of these solutions is evaluated for different wall assemblies, i.e. ETICS, masonry, structural insulated panels and wood-frame construction. Laboratory experiments were conducted on a full-scale test setup with a window of 1,01 m high and 0,56 m wide. Test results showed that it is not evident to obtain watertight face-sealed window-wall interfaces without an additional airtight layer or drainage possibilities. Water ingress was often recorded at lower pressure differences.

scholarly journals Telling the boiling frog what he needs to know: why climate change risks should be plotted as probability over time

2019 ◽  
Vol 2 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Simon Sharpe
Keyword(s):  
Climate Change ◽  
First Principles ◽  
Scientific Community ◽  
Health And Safety ◽  
Climate Science ◽  
Decision Makers ◽  
Intergovernmental Panel ◽  
Climate Change Risks ◽  
Science Community ◽  
Over Time

Abstract. Humanity's situation with respect to climate change is sometimes compared to that of a frog in a slowly boiling pot of water, meaning that change will happen too gradually for us to appreciate the likelihood of catastrophe and act before it is too late. I argue that the scientific community is not yet telling the boiling frog what he needs to know. I use a review of the figures included in two reports of the Intergovernmental Panel on Climate Change to show that much of the climate science communicated to policymakers is presented in the form of projections of what is most likely to occur, as a function of time (equivalent to the following statement: in 5 min time, the water you are sitting in will be 2 ∘C warmer). I argue from first principles that a more appropriate means of assessing and communicating the risks of climate change would be to produce assessments of the likelihood of crossing non-arbitrary thresholds of impact, as a function of time (equivalent to the following statement: the probability of you being boiled to death will be 1 % in 5 min time, rising to 100 % in 20 min time if you do not jump out of the pot). This would be consistent with approaches to risk assessment in fields such as insurance, engineering, and health and safety. Importantly, it would ensure that decision makers are informed of the biggest risks and hence of the strongest reasons to act. I suggest ways in which the science community could contribute to promoting this approach, taking into account its inherent need for cross-disciplinary research and for engagement with decision makers before the research is conducted instead of afterwards.

scholarly journals Methodological Proposal for the Development of Insurance Policies for Building Components

CivilEng ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 1-9
Author(s):  
Miguel Macedo ◽  
Jorge de Brito ◽  
Carlos Oliveira Cruz ◽  
Ana Silva
Keyword(s):  
Prediction Models ◽  
Methodological Approach ◽  
Insurance Coverage ◽  
Building Envelope ◽  
Premature Failure ◽  
Risk Premiums ◽  
Insurance Policies ◽  
Different Types ◽  
Building Components ◽  
Structured Approach

Insurance is a growing economic activity within the construction sector. Homes and buildings are perhaps the most important investment an individual makes in his/her lifetime. Nevertheless, the market for insurance coverage policies applied to the building envelope is in an embryonic stage, mainly due to the lack of knowledge in terms of risk and costs associated to the failure of these elements. This study provides an innovative and methodological approach to the development of an insurance product that targets the obsolescence of building components. In defining a structured approach to the design of insurance policies for buildings, the use of the service life prediction models proposed in this study allows establishing different types of insurance policies with different risk premiums and evaluating different losses and risks accepted by the owners, thus promoting the increase of the patrimonial value of the asset and reducing the risk of premature failure and the uncertainty of the costs of maintenance during its life cycle.

scholarly journals Dynamic Incentive-Aware Learning: Robust Pricing in Contextual Auctions

2020 ◽  
Author(s):  
Negin Golrezaei ◽  
Adel Javanmard ◽  
Vahab Mirrokni
Keyword(s):  
Decision Maker ◽  
Strategic Behavior ◽  
Learning Algorithm ◽  
Online Advertising ◽  
Ground Truth ◽  
Decision Makers ◽  
Effective Learning ◽  
Reserve Prices ◽  
Feedback Data ◽  
Over Time

In many practical settings, the decision makers have to learn their best actions by experimenting with possible options and collecting feedback (data) over time. It is often assumed that the collected data can be trusted as they reflect the ground truth. But this assumption is violated when the data are generated by strategic players. Consider online advertising market in which the ad exchange (decision maker) aims at learning the best reserve prices in the repeated auctions. In this setting, the data are advertisers’ submitted bids. Such data can be strategically corrupted by advertisers to trick the learning algorithm of the ad exchange to offer them lower reserve prices in the future auctions. In “Dynamic Incentive-Aware Learning: Robust Pricing in Contextual Auctions,” N. Golrezaei, A. Javanmard, and V. Mirrokni design effective learning algorithms with sublinear regret in such environments that are robust to the strategic behavior of the players.

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