bluuebunny/crossref_metadata_2025 huggingface dataset:
Stope Stability Assessment and Effect of Horizontal to Vertical Stress Ratio on the Yielding and Relaxation Zones Around Underground Open Stopes Using Empirical and Finite Element Methods
Authors: Sepehri Mohammadali , Apel Derek , Liu Wei
Published: October 2017

Predicting the stability of open stopes can be a challenging task for underground mine engineers. For decades, the stability graph method has been used as the first step of open stope design around the world. However, there are some shortcomings with this method. For instance, the stability graph method does not account for the relaxation zones around the stopes. Another limitation of the stability graph is that this method cannot to be used to evaluate the stability of the stopes with high walls made of backfill materials. However, there are several analytical and numerical methods that can be used to overcome these limitations. In this study, both empirical and numerical methods have been used to assess the stability of an open stope located between mine levels N9225 and N9250 at Diavik diamond underground mine. It was shown that the numerical methods can be used as complementary methods along with other analytical and empirical methods to assess the stability of open stopes. A three dimensional elastoplastic finite element model was constructed using Abaqus software. In this paper a sensitivity analysis was performed to investigate the impact of the stress ratio “k” on the extent of the yielding and relaxation zones around the hangingwall and footwall of the understudy stope.
Preparation of CaO-SiO2-CuO bioactive glasses-embedded anodic alumina with improved biological activities
Authors: Ni Siyu , Mei Lin , Ni Shirong , Cui Ran , Li Xiaohong , Hong Feng , Webster Thomas J. , Wu Chengtie
Published: October 2017

To improve bone cell cytocompatibility properties of porous anodic alumina (PAA) and implement anti-bacterial properties, amorphous CaO-SiO
An intensive presentations course in English for aeronautical engineering students using cyclic video recordings
Authors: Tatzl Dietmar
Published: October 2017

This article presents the design and evaluation of an intensive presentations course for aeronautical engineering students based on cyclic video recordings. The target group of this course in English for specific purposes (ESP) were undergraduate final-year students who needed to improve their presentation and foreign language skills to prepare for graduation and the workplace or further studies. This evaluative practitioner case study employed a mixed-methods design relying on a tailored paper questionnaire survey, teacher-assessed final presentations and teacher observation in class. Respondents were asked to rate course-related statements on language learning and presentation skills development on a 5-point Likert scale. With two student year groups in consecutive years, attendance at and engagement in the course were high, and student evaluations (N=41) suggested that the course had met its targets. Both the questionnaire ratings and the free verbal survey feedback were overwhelmingly positive and accorded with teacher-assessed student performance in the final presentations. The interactive, practice-oriented and video-backed design features, therefore, enabled students to develop their language as well as presentation skills through aviation-related contents. Even though the setting presented involves aeronautical engineering students, instructors in similar Science, Technology, Engineering and Mathematics (STEM) and other academic contexts will be able to adapt the concept behind this course to their own specific teaching situations.
Mother-tongue diversity in the foreign language classroom: Perspectives on the experiences of non-native speakers of English studying foreign languages in an English-medium university
Authors: Bruen Jennifer , Kelly Niamh
Published: October 2017

This paper considers the position of university language students whose mother tongue is other than the medium of instruction. Specifically, it investigates the attitudes and experiences of non-native English speakers studying either German or Japanese as foreign languages at an English-medium university. The findings indicate that the non-native speakers (NNSs) of English consider themselves to be at an advantage over the native speakers (NSs) of English in the study of German and Japanese as Foreign Languages, despite the fact that the medium of instruction is English, at least in the early stages of the language module. This is primarily owing to the fact that the non-native English speakers are already experienced language learners with an extensive linguistic repertoire. This view is supported by the NSs of English. Some concerns are expressed by non-native speakers of English in relation to an assumed knowledge of culture and society of the host country. The implications of these findings are discussed. Diverging from previous studies, this research focuses on learners of languages other than English and contributes to recent discussions on the increase in linguistic and cultural diversity and its impact within the foreign language classroom.
Giving learners a multicultural voice: An English speaking university context
Authors: Nunan Anna
Published: October 2017

Difficulties establishing support for English speakers taking second language electives in postsecondary education in Ireland led to research on how language classes could be more accessible, multicultural, plurilingual and relevant for students in a university language centre. It is important to try and discover why students choose a foreign language module in an English speaking context, how prior experiences of language learning are processed by these students and how student suggestions for future semester offerings may be relevant to changing paradigms in language learning. 2,600 student evaluations over 3 semesters were analysed in relation to student motivation in taking a foreign language elective. 25 students were interviewed on their motivation in language learning, prior experience of language learning and suggestions for future language modules. Motivation in language learning is a complex process (
Re-thinking the Veil, Jihad and Home in Fadia Faqir’s Willow Trees Don’t Weep (2014)
Authors: Sarnou Dallel
Published: October 2017

In her latest novel Willow Trees Don’t Weep(2014), the writer Fadia Faqir decided to go against the grain as a Muslim woman coming from the Middle East but lives in Britain and write about jihad, terrorism and Taliban. In this novel, the author negotiates meanings of secularism, fundamentalism, jihad, fathering, women and wars. The novel’s protagonist, Najwa is torn between her mother’s secularism and her father’s religious fundamentalism. In her homeland, Amman, Najwa is different from many other girls of Amman because she does not wear the headscarf that represents hijab, a religious garment, in many Muslim countries. However, when she travels to Afghanistan to trace her father, Najwa meets women wearing the burqaa, a head-to-toe veil. This might be an unexpected re-consideration of this garment as a symbol of freedom because she met veiled women who are self-determined and emancipated from within. Therefore, this article sets out to explore how the novel’s protagonist re-considers the veil, home and self-discovery.
A study of domestic honeymoon tourism in Turkey
Authors: Ünal Caner , Dursun Aslıhan , Caber Meltem
Published: October 2017

Honeymoon tourism is an important research area in tourism and travel literature because of its increasing economic importance for host destinations and their specific niche market characteristics. This study used a survey to investigate demographics, the importance of attributes in destination selection, overall satisfaction, loyalty and souvenir purchase preference amongst 540 domestic honeymoon tourists visiting Antalya, Turkey. It also identified in the context of destination marketing both domestic and international competitors of Antalya as a honeymoon destination. The results offered market-specific knowledge about honeymoon tourism in Turkey, such as the identification of the most important attributes in destination selection, tourists’ souvenir purchases, overall satisfaction and loyalties. The study concludes with a discussion of theoretical and managerial implications of the findings and recommendations for future study.
Symmetric convergence of double series whose coefficients are the quotients of divisions of complex Fourier coefficients by their indexes
Authors: Dzagnidze Omar
Published: October 2017

The symmetric and uniform convergence of the series

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\sum_{|m|\geq 1,|n|\geq 1}\frac{1}{mn}F_{mn}e^{imx},\quad\sum_{|m|\geq 1,|n|%
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\frac{1}{mn}F_{mn}e^{i(mx+ny)}

on

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is established.
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of a function f which is summable on

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Critical global citizenship: contextualising citizenship and globalisation
Authors: Mansouri Fethi , Johns Amelia , Marotta Vince
Published: October 2017

This introductory paper to our first issue provides reflection on the concept of critical global citizenship at both theoretical and practical levels. We maintain that ‘citizenship’, irrespective of its level of articulation (i.e. national, international, global, etc.) remains an issue that reflects a status, a feeling and practices that are intrinsically interlinked. As a legal status, formal citizenship allows individuals to form a sense of belonging within a political community and, therefore, empowers them to act and perform their citizenship within the spatial domains of the nation-state. Critical global citizenship, asks these same individuals not so much to neglect these notions of belonging and practice to a particular locale, but to extend such affinities beyond the territorial boundaries of their formal national membership and to think critically and ethically about their local, national and global relationship with those who are different from themselves. Making a case for a critical global citizenship, however, also requires acknowledging material inequalities that affect the most vulnerable (i.e. migrants, asylum seekers, those experiencing poverty, etc.) and which mean that efforts to cultivate global citizenship orientations to address social injustice are not enacted on an even playing field. As such, a critical global citizenship approach espouses a performative citizenship that is at once democratic and ethical, as well as being aimed at achieving social peace and sustainable justice, but which is also affected by material conditions of inequality that require political solutions and commitment from individuals, states, non-governmental organisations (NGOs) and civil society organisations.
Contemporary Citizenship: Four Types
Authors: Turner Bryan S.
Published: October 2017

The paper begins with an examination of three ideal types citizenship which are not necessarily mutual exclusive. The first type is national citizenship, typically associated with ethno-nationalism. The second form is social citizenship or ‘welfare citizenship’ refers to the creation of social rights and is closely connected to civil-society institutions rather than to the state or market. The third form of citizenship identifies the citizen with participation in the work force emphasizing self-reliance and autonomy. In this discussion, I argue that with economic globalization and the development of neo-liberal strategies the various forms of citizenship have converged towards a new model of passive citizenship in which the state is or has withdrawn from commitment to full employment and the provision of social security, especially universal provision of welfare services, and civil-society institutions have been eroded. The result is the emergence of the apolitical,isolated citizen as consumer. The fourth model of citizenship presupposes a consumer society, a weak state and the decline of civic institutions, where the passive citizen becomes a consumer of privatized goods and services. The rise of a fourth model of citizenship – the consumer-citizen – can be interpreted as a logical consequence of financialization.
Intercultural Public Intellectual Engagement
Authors: Modood Tariq
Published: October 2017

The article firstly examines the different conceptions of dialogue and reason within political theory, especially in the work of Rawls. Secondly we explore multicultural political theorists who have been motivated less by abstract reasoning by a sole reasoner or identical identity-less individuals and more by dialogue. For such multiculturalists, the principles of social justice are not known in advance or simply by reason, but are arrived at by conflict and learning, by dialogue and negotiation in circumstances of inequality and minority-claims making. In response to the multiculturalists, interculturalists allege that multiculturalism is too focused on the macro and the conflictual, and dialogue should be redirected to the micro and the cooperative. Although I welcome the interculturalists’ focus on micro-relations, this does not require abandoning the idea of dialogue at the level of political controversies and public discourses. It is not an either–or choice because groups and intergroup problems exist in society and cannot be simply handled at a micro level of contact, interaction and sociability. The kind of macro-level dialogue that I am speaking of can also be understood as a form of public intellectual engagement that can contribute to societal dialogues.
The Decline and Resurgence of Turkish Islamism: The Story of Tayyip Erdoğan’s AKP
Authors: Yilmaz Ihsan , Barton Greg , Barry James
Published: October 2017

For decades, Turkish Islamists have failed to attract the votes of large sections of society and remained marginal. As a result of this failure to come to power, and due to domestic and international constraints and windows of opportunities, they have declared that they have jettisoned Islamism. Many Turkish Muslims whose religious disposition was shaped by the pluralistic urban Ottoman experience and small-town Anatolian traditionalism, and by the contesting currents of cosmopolitan pluralism and rural social conservatism, voted in favour of these former Islamists who have become “Muslim Democrats”. This paper elaborates on the genealogy of Turkish Islamists and their political trajectories and argues that when the forces and constraints of domestic and external social, political and economic conditions disappeared and the opportunities derived from being Muslim Democrats no longer existed, the former Islamists easily returned to their original ideology, showing that despite assertions to the contrary their respect for democracy and pluralism had not truly been internalised. This paper also aims to demonstrate that similar to other authoritarian populists, Erdoganists perceive the state and its leader as more important than anything else and as being above everything else, which has culminated in a personality cult and sanctification of the state. As long as Turkey’s economy continued to boom, almost everyone was happy that Turkey could readily market the “Muslim Democrats” story to the whole world for a long period as a major success story, or as an “exemplary Muslim country” or “model”. Yet, Middle Eastern elites and Western forces got carried away and learnt the hard way just how naive their view was in perhaps the first great transformation movement of the twenty-first century – the Arab Spring. Likewise, the Turkish Spring turned all too quickly towards autumn and then winter.
Multifractal characterization of epitaxial silicon carbide on silicon
Authors: Ţălu Ştefan , Stach Sebastian , Ramazanov Shikhgasan , Sobola Dinara , Ramazanov Guseyn
Published: October 2017

The purpose of this study was to investigate the topography of silicon carbide films at two steps of growth. The topography was measured by atomic force microscopy. The data were processed for extraction of information about surface condition and changes in topography during the films growth. Multifractal geometry was used to characterize three-dimensional micro- and nano-size features of the surface. X-ray measurements and Raman spectroscopy were performed for analysis of the films composition. Two steps of morphology evolution during the growth were analyzed by multifractal analysis. The results contribute to the fabrication of silicon carbide large area substrates for micro- and nanoelectronic applications.
The crystal structure (E)-4-methyl-N′-(2-nitrobenzylidene)benzenesulfonohydrazide, C14H13N3O4S
Authors: Xi-Shi Tai , Peng-Fei Li
Published: October 2017

C14H13N3O4S, triclinic, P1̅ (no. 2), a = 5.6735(11) Å, b = 10.509(2) Å, c = 12.180(2) Å, α = 93.76(3)°, β = 95.11(3)°, γ = 98.13(3)°, V = 713.8(2) Å3, Z = 2, R
gt(F) = 0.0446, wR
ref(F
2) = 0.1179, T = 293(2) K.
Coupling of subcritical methanol with acidic ionic liquids for the acidity reduction of naphthenic acids
Authors: Zafar Faisal , Mandal Pradip Chandra , Shaari Ku Zilati Bt Ku , Ullah Zahoor
Published: October 2017

The presence of naphthenic acids (NAs) in crude oil is the major cause of corrosion in the refineries and its processing equipment. The goal of this study is to reduce the total acid number (TAN) of NAs by treating them with subcritical methanol in the presence of acidic ionic liquid (AIL) catalysts. Experiments were carried out in an autoclave batch reactor and the effect of different reaction parameters was investigated. It was observed that TAN reduction was positively dependent on the temperature and concentration of the AIL whereas excess of methanol has a negative effect. Approximately 90% TAN reduction was achieved under the optimized reaction conditions using [BMIM]HSO4 as catalyst. It was also perceived from the experimental results that the AILs with longer alkyl chain exhibited higher catalytic activity. The activity and stability of AIL showed that they can be promising catalyst to esterify NAs under subcritical methanol.
Chiral pyrrolidinium salts derived from menthol as precursor – synthesis and properties
Authors: Janus Ewa , Gano Marcin
Published: October 2017

Six new chiral pyrolidinium salts with chiral substituent at quaternary nitrogen atom were synthesized with high overall yields from (-)-menthol as cheap chiral precursor and were identified by NMR and HRMS spectroscopy. It was shown that anion type had the effect on chemical shift of protons adjacent to quaternary nitrogen atom and physical properties of these salts. Salts with NTf2 or NPf2 were in a liquid state at room temperature and characterized with the highest thermal stability among others. Furthermore, chiral ionic liquid with NTf2 anion was used as solvent in Diels-Alder reaction and gave higher yield and stereoselectivity than in ionic liquids with achiral cations. Synthesized chiral salts have the potential as chiral solvents in synthesis and auxiliaries in analytical methods to improve chiral recognition.
Computational Investigation of Cationic, Anionic and Neutral Ag2AuN (N = 1–7) Nanoalloy Clusters
Authors: Ranjan Prabhat , Chakraborty Tanmoy , Kumar Ajay
Published: October 2017

The study of bimetallic nanoalloy clusters is of immense importance due to their diverse applications in the field of science and engineering. A deep theoretical insight is required to explain the physico-chemical properties of such compounds. Among such nanoalloy clusters, the compound formed between Ag and Au has received a lot of attention because of their marked electronic, catalytic, optical and magnetic properties. Density Functional Theory (DFT) is one of the most successful approaches of quantum mechanics to study the electronic properties of materials. Conceptual DFT-based descriptors have turned to be indispensable tools for analysing and correlating the experimental properties of compounds. In this report, we have investigated the ground state configurations and physico-chemical properties of Ag2AuNλ(N= 1–7,λ=±1, 0) nanoalloy clusters invoking DFT methodology. Our computed data exhibits interesting odd-even oscillation behaviour. A close agreement between experimental and our computed bond length supports our theoretical analysis.
Vortices at Microwave Frequencies
Authors: Silva Enrico , Pompeo Nicola , Dobrovolskiy Oleksandr V.
Published: October 2017

The behavior of vortices at microwave frequencies is an extremely useful source of information on the microscopic parameters that enter the description of the vortex dynamics. This feature has acquired particular relevance since the discovery of unusual superconductors, such as cuprates. Microwave investigation then extended its field of application to many families of superconductors, including the artificially nanostructured materials. It is then important to understand the basics of the physics of vortices moving at high frequency, as well as to understand what information the experiments can yield (and what they can not). The aim of this brief review is to introduce the readers to some basic aspects of the physics of vortices under a microwave electromagnetic field, and to guide them to an understanding of the experiment, also by means of the illustration of some relevant results.
Scaling morphosemantic transparency/opacity: A corpus-linguistic and acquisitionist study of German diminutives
Authors: Schwaiger Sonja , Ransmayr Jutta , Korecky-Kröll Katharina , Sommer-Lolei Sabine , Dressler Wolfgang U.
Published: October 2017

The judicious use of electronic corpora allows new possibilities in the study of word formation. In contrast to the usual way of contrasting morphosemantic transparency (or compositionality) and morphosemantic opacity (or non-compositionality) in a dichotomous way, we present a ten-step scale from maximum transparency to total opacity, exemplified with the common German diminutive suffixation in -chen and Austro-Bavarian -erl. Our corpus-linguistic investigation allows new insights into problems of distribution of type and token frequency according to degrees of morphosemantic transparency/ opacity and of the two rivalling diminutive formations. An analysis of diminutive acquisition is added as external evidence for or against previous claims. Acquisition data come from three longitudinal corpora and from 24 children of a transversal quasi-longitudinal study. Here the order of acquisition of diminutives according to the ten-step scale of morphosemantic transparency/opacity and to adult type and token frequency will be presented and the relation between morphosemantic and morphopragmatic meaning will be discussed.
Hygrothermal Performance Assessment of Stucco-Clad Wood Frame Walls Having Vented and Ventilated Drainage Cavities
Authors: Saber Hamed H. , Lacasse Michael A. , Moore Travis V.
Published: October 2017

The long-term performance in respect to moisture management within any wood frame wall assembly depends on the hygrothermal response of the wall to local climate moisture loads. Estimating the wood moisture content, temperature, and time of exposure to conditions suitable for the onset, growth, and propagation of mold or rot are critical parameters when assessing the longevity of wood frame structures. A number of approaches for assessing the vulnerability of wood frame structures to deterioration have been developed in recent years; one of which has been used by NRC-Construction for evaluating the performance of wall assemblies based on the results from hygrothermal simulation. In this paper, an example of the use of this approach for the assessment of a stucco-clad wall incorporating drainage cavities is described as is the use of a mold index to capture the risk of the formation of mold in walls. An example is given in assessing the moisture management of a stucco-clad wood frame wall incorporating vented and ventilated drainage cavities for three Canadian locations.
Simulating the Thermal Impact of Masonry Ties
Authors: Asava Ryan , Rusu Zachary A.
Published: October 2017

In masonry veneer wall assemblies, lateral ties are a structural requirement. Traditionally they are fabricated from steel, which has a high conductivity. Building codes require that ties be tightly spaced and, in most climate zones, it requires continuous insulation in the majority of wall assemblies. Continuous insulation in the cavity space results in the ties penetrating the insulation layer. The combination of material, required spacing, and location of insulation result in most masonry veneer walls being constructed with a significant amount of thermal bridges causing a loss in thermal performance.

At present, the building industry typically does not account for these thermal bridges and their effect on the exterior enclosure. We speculate that the reasoning for this is primarily due to a lack of industry accepted information relative to the thermal reduction of the masonry wall system from the inclusion of ties. The purpose of this paper is to begin providing this missing information. Using three dimensional Finite Element Modeling software (thermal modeling), common masonry wall assemblies are studied by simulating them with and without masonry ties. This comparative analysis quantifies the impact of masonry ties on the thermal performance of each wall assembly studied.

In recent history, large steps, such as continuous insulation requirements, thermally broken fenestration systems, low-e coatings, and air barrier technologies have been introduced to increase the performance of exterior enclosures and thus the overall efficiency of the built environment. The industry now must focus its attention on the details of wall systems to take the next steps in incrementally increasing building efficiency. Data obtained through three dimensional thermal modelling is used to address the impact masonry ties have on the thermal performance of wall systems. Finally, alternate materials are evaluated and considered as a means to improve thermal performance of the masonry veneer wall assemblies.
Practical Application of Coupled FEA and CFD Steady State Analysis for the Prediction of Nighttime Building Enclosure Surface Temperatures
Authors: Boone Justin L. , Pugh Elizabeth R.
Published: October 2017

Coupled three-dimensional finite element analysis (3D-FEA) and computational fluid dynamics (CFD) software packages used to simulate heat transfer and airflow can be valuable tools for predicting and comparing the thermal performance of building enclosure components, assemblies, and systems when validated and used consistently. Today, the most commonly used tools are two-dimensional FEA (2D-FEA) programs that have been developed as part of efforts to establish uniform methods of evaluation to compare conduction-dominated heat transfer through building envelope elements, primarily fenestration systems. Increasingly, these tools are being used to predict in-service surface temperatures of building enclosure assemblies, particularly for the risk of interior condensation. However, these commonly used 2D-FEA tools have substantial limitations. They typically do not explicitly model radiation between objects or convective fluid flows, each of which can significantly affect heat transfer at element surfaces. They also cannot account for conditions that vary in three dimensions. As a result of these limitations, the computational tools most commonly used today cannot accurately predict surface temperatures that are significantly affected by convective currents, surface radiation, or three-dimensional variations in relevant factors. Coupled 3D finite element analysis and computational fluid dynamics (3D-FEA-CFD) software packages that can explicitly model convection, radiation and three dimensions are now commercially available, and more advanced analyses can be performed. Because many of these multiphysics packages were initially developed for mechanical applications, relatively little work has been done to evaluate their use in the study and design of building enclosure systems. The objective of this study is to develop and evaluate a practical methodology for using a 3D-FEA-CFD package to predict nighttime in-service building enclosure surface temperatures. The evaluation includes instrumentation and data collection from a test space, 3D-FEA-CFD simulation of the instrumented assemblies, assessment of basic simulation accuracy, comparison to 2D analysis results, and an analysis of sensitivity to selected simulation variables.
Analysis of Improved Criteria for Mold Growth in ASHRAE Standard 160 by Comparison with Field Observations
Authors: Glass Samuel V. , Gatland Stanley D. , Ueno Kohta , Schumacher Christopher J.
Published: October 2017

ASHRAE Standard 160, Criteria for Moisture-Control Design Analysis in Buildings, was published in 2009. The standard sets criteria for moisture design loads, hygrothermal analysis methods, and satisfactory moisture performance of the building envelope. One of the evaluation criteria specifies conditions necessary to avoid mold growth. The current standard requires that the 30-day running average relative humidity at the material surface be less than 80 % when the 30-day running average surface temperature is between 5°C (41°F) and 40°C (104°F). This criterion was intended to strike a balance between the need for simplicity to make the standard useful and the complex reality of mold growth, which varies with mold species and depends on the type of material, water activity, temperature, and other factors. Since the standard was published, many practitioners have maintained that the mold criterion is too stringent. Assemblies known to have satisfactory performance in the field do not meet the criterion under hygrothermal simulation. A recent addendum to ASHRAE Standard 160 replaced the simplified mold criterion with a state-of-the-art empirical model that describes mold growth and decline over time using a mold index. This model takes into account the sensitivity of the material, the surface temperature, and the surface relative humidity. This paper provides an overview of the mold index model and a series of comparisons between field observations of visible mold growth or lack thereof on wood-based sheathing and model predictions that use measured surface temperature and relative humidity values as inputs. The field data are from published studies on above-grade wood-frame wall assemblies and roof assemblies covering a range of climate zones. Our analysis indicates that the current 30-day criterion in ASHRAE Standard 160 fails many assemblies in which visible mold growth did not occur. In contrast, the mold index model predictions give better agreement with observations.
Hygrothermal Impact of Adhesive-Applied Rooftop Photovoltaic System
Authors: Shukla Nitin , Watts Alliston , Honeker Christian , Kośny Jan
Published: October 2017

Adhesive mounting of photovoltaic (PV) modules on residential roofs can significantly reduce the installed cost. The potential for undesirable moisture buildup under the module, however, may reduce shingle life and degrade the underlying roof elements. High moisture levels in roof elements may also adversely affect the energy performance of the building. This study investigates whether an adhesively mounted PV system causes a preferential moisture buildup under the module on an asphalt shingle roof. Lightweight PV modules were adhesively mounted on half of the roof of an instrumented test hut located in Boston, MA. Moisture pin sensors, installed in various locations of the roof deck, determined the moisture content (MC) of the wood in the roof assembly. The MC is found to follow a seasonal pattern: lower values (7–11 %) during the summer and higher values (11–15 %) during the winter. MC measurements during the winter and summer seasons showed no adverse impact of the adhesive-mounted rooftop PVs on the hygrothermal behavior of the underlying roof deck element over the 1-year measurement period.
Three-Dimensional Condensation Risk Analysis of Insulated Curtain Wall Spandrels
Authors: Dunlap Andrew , Asava Ryan
Published: October 2017

Current methods of evaluating the risk of condensation on fenestration systems generally include two-dimensional computer modeling and sometimes laboratory testing. This is not sufficient for curtain wall systems that incorporate areas of insulated spandrel. In most curtain walls, mullions can extend from a warmer interior environment into a colder insulated spandrel. The mullions function as thermal bridges and may increase the potential for condensation on or within the system. The impact will vary depending on several factors such as the type of vision and spandrel glazing, insulating glass unit (IGU) spacer type, insulation thickness, location of the insulation, and vapor barrier methodology. Industry standard evaluation methods do not address this heat transfer. Two-dimensional computer modeling can be used to assess transitions between vision and spandrel areas. Because it is only a two-dimensional evaluation, it cannot determine the heat flow in the third dimension. Laboratory testing such as the American Architectural Manufacturers Association’s AAMA 1503, Voluntary Test Method for Thermal Transmittance and Condensation Resistance of Windows, Doors, and Glazed Wall Sections, is sometimes used to provide measured results of condensation resistance. Manufacturers typically do not include spandrel conditions when testing the performance of a system. The purpose of this paper is to evaluate the relative impact of three-dimensional heat flow through curtain wall vision/spandrel conditions related to the potential for condensation to determine if there is an increased risk of condensation at the vision/spandrel interface and to demonstrate that the use of three-dimensional thermal modeling can be readily repeated for multiple project specific variables without the cost of laboratory testing.
Simulations of Indoor Moisture Generation in U.S. Homes
Authors: Pallin Simon , Boudreaux Philip , Jo Soo Jeong , Perez Meghan , Albaugh Amy
Published: October 2017

In residential buildings, there are many sources that contribute to the total hourly moisture generation, including occupants and their activities as well as some appliances. In cases of high indoor moisture generation, indoor air quality, building envelope durability, and heating, ventilation, and air conditioning efficiency can all be compromised. Oak Ridge National Laboratory designed a simulation tool, the generation of indoor heat and moisture (GIHM) tool, to capture the probabilistic nature of hourly indoor moisture and heat generation caused by residential building type, occupant behavior, climate zone, incidences of appliances, and other variables. In this paper, we focus on the moisture aspect of this tool. Results from the GIHM tool, as sets of hourly profiles of indoor moisture generation for specifically defined households, can be used as inputs for building energy simulation software, such as EnergyPlus. If many of these profiles are used as inputs, then the performance of an energy efficiency measure can be evaluated for the range of expected operating conditions in different homes. The GIHM tool can aid in designing heating, ventilation, and air conditioning systems that control temperature and humidity well, accessing the moisture durability of envelope components and understanding how different building designs and materials affect occupant comfort.
Demonstration of the Hygrothermal Performance of a Next-Generation Insulation Material in a Cold Climate
Authors: Biswas Kaushik , Desjarlais Andre , Jiang Timothy , Patel Tapan , Nelson Andrew , Smith Douglas
Published: October 2017

Energy loss through building walls is estimated to cost the U.S. Department of Defense (DOD) about $200 million per year, accounting for 5 % of the total energy cost in DOD facilities. This article describes the demonstration of a high-performance insulation material, called modified atmosphere insulation (MAI), to reduce wall-related heat losses in a DOD building located in Ft. Drum, NY, in a cold climate. MAI has been demonstrated to achieve R32/in. (hr-ft2-°F/Btu-in) or greater and its use can significantly increase the thermal resistance of walls with a marginal increase in wall thickness, making it an ideal candidate for retrofit application. MAI is a variant of vacuum insulation panels produced at a substantially reduced cost resulting from a change in the evacuation process. By retrofitting walls and increasing thermal resistance, as measured by R-value, by R10-20 (h-ft2-°F/Btu), reductions of 30 % or more over baseline wall-generated space conditioning loads are possible. Further, with targeted applications for older or more poorly insulated facilities, greater energy savings can be achieved. In this article, the installation of MAI panels in an existing building at Ft. Drum and the resulting energy benefits will be described. Like vacuum insulation panels, MAI panels consist of an evacuated nanoporous core that is encapsulated within air- and vapor-impermeable barrier films. Addition of these impermeable barrier films can have implications on the moisture storage and movement within the wall systems. Therefore, in addition to the thermal performance evaluation, measurements and modeling will be used to determine the hygric behavior of the retrofitted walls.
What Does “Perm” Mean? The Difference between Permeability and Water Vapor Transmission Rates in Air Barrier Materials
Authors: Wagner Andrea , Yee Stanley , Brasseur Michael
Published: October 2017

Permeability is a normalized term that is calculated based on vapor flow, vapor drive, and saturation pressures. However, it does not take into account the total volume of water vapor that is actually transmitting across a wall assembly at a given temperature and relative humidity. It also does not take into account other factors, which may include chemical diffusion and moisture content concentration. This paper will present water vapor transmission data collected on a variety of air barrier membranes, both permeable and non-permeable, at different temperatures and relative humidity. These data show a variation in permeability as a function of temperature; however, this is not reflected in ASTM E96, Standard Test Methods for Water Vapor Transmission of Materials, Methods A and B, the standardized perm rating often used by professionals to design wall assemblies. Hygrothermal analysis tools primarily use a permeability input based on relative humidity and do not directly consider temperature outside of the general Schirmer equation. This paper will provide an initial look at the implications of this limitation based on the vapor drive data through the use of hygrothermal analysis and wall assembly testing. The aforementioned may have intriguing implications on how we assess materials selected for exterior wall assemblies in construction. These same implications potentially influence how the industry establishes performance metrics and how they may relate to a wall assembly’s actual performance. This paper will serve to initiate a candid discussion on the subject matter.
Modeling of Aerogel Blanket Insulation Applications in Exterior Wall Constructions
Authors: Mukhopadhyaya Phalguni , Carbary Lawrence D. , Yee Stanley , Appelfeld David , Pahwa Gagandeep Singh
Published: October 2017

Green building practices, net-zero targets for buildings, and new energy codes for buildings around the world are creating demands for high-performance thermal insulation materials. Aerogel blanket is a high-performance thermal insulation having thermal resistance two to three times higher than traditional thermal insulation materials. Aerogel in blanket form is an extremely convenient material for building envelope constructions and can be cut to any reasonable size or shape. The blanket is usually available in a 10-mm thickness and can be applied, if necessary, in multiple layers. This paper assesses the implications of added aerogel thermal insulation in three different wall systems (commercial, residential, and heritage) on their moisture management performance. The hygrothermal simulation tool WUFI® Pro 5.3 was used to carry out more than 50 simulations in five different locations (Wilmington, NC; Vancouver, BC; Minneapolis, MN; Chicago, IL; and Baltimore, MD) in North America. Simulation results demonstrate that appropriate design and construction techniques can successfully integrate aerogel blanket insulation in energy-efficient commercial, residential, and heritage wall constrictions without compromising long-term performance or durability caused by poor moisture management.
Comparing the Enclosure Wall Performance of Low-Permeance Exterior Insulation to High-Permeance Exterior Insulation in the Pacific Northwest
Authors: Smegal Jonathan , Finch Graham , Nieto Alejandra , Schumacher Chris
Published: October 2017

As the energy efficiency of buildings improves, the amount of insulation on the exterior of the enclosure will increase because of both energy- and durability-related benefits. There are a large number of papers that have addressed the misconception that exterior insulation increases the durability risk of the enclosure. However, an argument remains concerning the relative performance of low- and high-permeance exterior insulations. RDH Building Science Laboratories has collected nearly two years of field data of full-scale exterior-insulated commercial and residential wall assemblies in side-by-side comparisons. The walls were insulated on the exterior with either low-vapor-permeance extruded polystyrene or high-vapor-permeance mineral wool exterior insulation. The walls were constructed on the north and south orientations of a test hut in a Pacific Northwest climate and were subjected to typical cool, high-humidity wintertime temperatures. The test hut interior relative humidity (RH) was kept at a constant level of 40 % or 50 % (slightly above average for the climate zone) to help determine the performance differences in the assemblies. The test walls were also subjected to intentional controlled wetting events to the exterior surfaces of the structural oriented strand board sheathing to simulate various construction defects and determine the relative rates of drying for the two assemblies. The test walls were compared using measured RH, measured wood moisture content, and the Finnish VTT Technical Research Centre’s mold index. Generally speaking, all of the walls (both mineral wool and extruded polystyrene) performed quite well under normal operating conditions, considering the higher than recommended interior RH conditions. Following the wetting events, the commercial and residential wall assemblies with higher permeance mineral wool continuous insulation generally had improved drying rates.
Long-Term Fragility of Y Chromosomes Is Dominated by Short-Term Resolution of Sexual Antagonism
Authors: Blackmon Heath , Brandvain Yaniv
Published: October 2017

Existing models of sex chromosome evolution do not address whether inversions can accumulate even if they cause difficulties in meiotic pairing. Blackmon..

The evolution of heteromorphic sex chromosomes has fascinated biologists, inspiring theoretical models, experimental studies, and studies of genome structure. This work has produced a clear model, in which heteromorphic sex chromosomes result from repeated fixations of inversions (or other recombination suppression mechanisms) that tether sexually antagonistic alleles to sex-determining regions, followed by the degeneration of these regions induced by the lack of sex chromosome recombination in the heterogametic sex. However, current models do not predict if inversions are expected to preferentially accumulate on one sex-chromosome or another, and do not address if inversions can accumulate even when they cause difficulties in pairing between heteromorphic chromosomes in the heterogametic sex increasing aneuploidy or meiotic arrest. To address these questions, we developed a population genetic model in which the sex chromosome aneuploidy rate is elevated when males carry an inversion on either the X or Y chromosome. We show that inversions fix more easily when male-beneficial alleles are dominant, and that inversions on the Y chromosome fix with lower selection coefficients than comparable X chromosome inversions. We further show that sex-chromosome inversions can often invade and fix despite causing a substantial increase in the risk of aneuploidy. As sexual antagonism can lead to the fixation of inversions that increase sex chromosomes aneuploidy (which underlies genetic diseases including Klinefelter and Turner syndrome in humans) selection could subsequently favor diverse mechanisms to reduce aneuploidy—including alternative meiotic mechanisms, translocations to, and fusions with, the sex chromosomes, and sex chromosome turnover.
Dual Roles of Glutathione in Ecdysone Biosynthesis and Antioxidant Function During Larval Development in Drosophila
Authors: Enya Sora , Yamamoto Chikana , Mizuno Hajime , Esaki Tsuyoshi , Lin Hsin-Kuang , Iga Masatoshi , Morohashi Kana , Hirano Yota , Kataoka Hiroshi , Masujima Tsutomu , Shimada-Niwa Yuko , Niwa Ryusuke
Published: October 2017

Ecdysteroids, including the biologically active hormone 20-hydroxyecdysone (20E), play essential roles in controlling many developmental and physiological events in insects. Ecdysteroid biosynthesis is achieved by a series of specialized enzymes encoded by the Halloween genes. Recently, a new class of Halloween gene, noppera-bo (nobo), encoding a glutathione S-transferase (GST) in dipteran and lepidopteran species, has been identified and characterized. GSTs are well known to conjugate substrates with the reduced form of glutathione (GSH), a bioactive tripeptide composed of glutamate, cysteine, and glycine. We hypothesized that GSH itself is required for ecdysteroid biosynthesis. However, the role of GSH in steroid hormone biosynthesis has not been examined in any organisms. Here, we report phenotypic analysis of a complete loss-of-function mutant in the γ-glutamylcysteine synthetase catalytic subunit (Gclc) gene in the fruit fly Drosophila melanogaster. Gclc encodes the evolutionarily conserved catalytic component of the enzyme that conjugates glutamate and cysteine in the GSH biosynthesis pathway. Complete Gclc loss-of-function leads to drastic GSH deficiency in the larval body fluid. Gclc mutant animals show a larval-arrest phenotype. Ecdysteroid titer in Gclc mutant larvae decreases, and the larval-arrest phenotype is rescued by oral administration of 20E or cholesterol. Moreover, Gclc mutant animals exhibit abnormal lipid deposition in the prothoracic gland, a steroidogenic organ during larval development. All of these phenotypes are reminiscent to nobo loss-of-function animals. On the other hand, Gclc mutant larvae also exhibit a significant reduction in antioxidant capacity. Consistent with this phenotype, Gclc mutant larvae are more sensitive to oxidative stress response as compared to wild-type. Nevertheless, the ecdysteroid biosynthesis defect in Gclc mutant animals is not associated with loss of antioxidant function. Our data raise the unexpected hypothesis that a primary role of GSH in early D. melanogaster larval development is ecdysteroid biosynthesis, independent from the antioxidant role of GSH.