bluuebunny/crossref_metadata_2025 huggingface dataset:
Unconventional Superfluidity in Ultracold Dipolar Gases
Authors: Domínguez-Castro G A , Paredes R
Published: June 2020

In this manuscript, we discuss the emergence of p-wave superfluidity in a dipolar Fermi gas confined in a double layer array of parallel optical lattices in two dimensions. The dipole moments of the molecules placed at the sites of the optical lattices, separated a distance L and pointing in opposite directions produce an effective attractive interaction among them, except between those dipoles situated one on top of the other. Such interaction between dipoles is precisely the origin of the non-conventional superfluid state. We present the analysis for the ground state of the many-body system within the mean-field scheme. In particular, we study the stable regions, as a function of the system parameters, namely the effective interaction between dipoles and the filling factor n, for which the superfluid state can exist. Following the BKT scheme, we estimate the critical temperature of the superfluid state.
Symmetries of the Renormalization Group Equations
Authors: Juárez W S R , Kielanowski P , Vázquez M L
Published: June 2020

The determination of the renormalization group equations in quantum field theory is a very laborious task. For example in the Standard Model the full set of these equations is known only up to two loops, while only some partial results are obtained at higher orders. We argue that one can simplify the calculation of the renormalization group equations by using the symmetry of a system. The origin of the simplification lies in the use of the invariant polynomials of the symmetry group of the theory. We consider a quantum field theory with three scalar fields that is invariant under the action of the permutation group S
3. We show, using the theorem of Molien, that for such a model there is a significant reduction of the amount of work needed for the derivation of the renormalization group equations.
Time Resolution Simulation Measurement for the Configuration Plastic Scintillator Material+SiPM and its Application to Medical Physics
Authors: Zepeda C H
Published: June 2020

The Silicon Photomultipliers (SiPMs) have been used more frequently in the last years compared to Photomultiplier Tubes (PMT), due to its low cost, lower bias operation voltage and its smaller size, which can be up to 1×1 mm2. In this work, it is shown the time resolution simulation results for two scintillating materials: BC404 and BC422 (20×20×3 mm3 of size)+ SiPM (3×3 mm2 of size). The studies of this configuration can replace the PMT and crystals, commonly used in a Positron Emission Tomography (PET). The time resolution can be improved to be able to make the greatest data collection, to use an isotope with less life time and thus perform less damage to the patient by radiation.
Visible light communication channel with a smartphone screen as a transmitter and color shift keying modulation for access control applications
Authors: Martínez-Ciro R A , Morales-Morales D M , López-Giraldo F E , Rojas-Usuga J D
Published: June 2020

Smartphones or tablets are a new kind of mobile device that allows developers the optical wireless communication. This enables a low-cost implementation interface with a visible light communication system. The present work aims to implement the access control system based on visible light communication channel with a smartphone screen as a transmitter and color shift keying modulation. The proposed system runs on the Samsung Galaxy notebook tablet to control the light colors emitted by the screen. We used Android Studio to develop the application for access control system. In this scheme, the optical response of the Galaxy screen to 4 color shift keying constellation design based on standard color space is also discussed. The proposed system is validated by experimental tests for access control applications. The results obtained suggest that a bit rate of 100 b/s can be achieved with a 4 color shift keying constellation format. It was concluded that the main advantage of using the Galaxy screen as a transmitter in a visible light communication lies in the low complexity to generate color shift keying modulation and its application on access control system. This can generate opportunities for this method to become realistic on mobile consumer electronics.
Experimental characterization of a tuneable all-fiber mode converter device for mode-division multiplexing systems
Authors: Galvis-Arroyave J L , Villegas-Aristizabal J , Montoya-Cardona J , Montoya-Villada S , Reyes-Vera E
Published: June 2020

In this work, we present a novel scheme to make a controllable, stable, and versatile all-fiber mode converter device. The converter consists of a few modes polarization-maintaining fiber, which is laterally stressed using an electrical actuator. The electrical actuator provides a simple mechanism to control the refractive index changes in the optical fiber thought the elasto-optic phenomena. Thus, it is possible obtain a platform to make mode conversion between the HE11 mode and the TE01, TM01 and HE21 modes. Likewise, the proposed methodology allows controlling the modal conversion trough the variation of the applied force. The results reveal that the performance of the converter depends on the input light polarization, the analyzer angle and the applied force. In addition, the device presents a compact size of 8 cm and shows an excellent performance when is analyzed at 980 nm. Thereby, it is suitable to be implemented for future optical fiber communication systems that employs mode-division multiplexing.
Generating density maps for convolutional neural network-based cell counting in specular microscopy images
Authors: Sierra J S , Pineda J , Viteri E , Tello A , Millán M S , Galvis V , Romero L A , Marrugo A G
Published: June 2020

Accurate endothelial cell density with specular microscopy is essential for correct clinical assessment of the cornea. Commercial specular microscopes incorporate automated cell segmentation methods to estimate cell density. However, these methods are prone to false cell detections in pathological corneas. This project aims to obtain a reliable automated cell density from specular microscopy images of both healthy and pathological corneas with convolutional neural networks. Convolutional neural networks require labeled datasets. Thus, we developed custom software for producing a curated dataset of labeled ground-truth images and cell density maps. In this paper, we implemented a fully convolutional regression network to predict the cell density map from the input microscopy image. Encouraging preliminary results show the potential of the method. This approach may pave the way for dealing with the variability of corneal endothelial cell images.
Colombian fruit and vegetables recognition using convolutional neural networks and transfer learning
Authors: Álvarez-Canchila O I , Arroyo-Pérez D E , Patiňo-Saucedo A , Rostro González H , Patiño-Vanegas A
Published: June 2020

Automatic image recognition is a convenient option for labeling and categorizing fruits and vegetables in supermarkets. This paper proposes the design and implementation of an automatic classification system for Colombian fruits, by training a convolutional neural network. A database was created to train and test the system, which consisted of 4980 images, labeled in 22 classes, each corresponding to pictures of the same kind of fruit, trying to reproduce the variability of a real case scenario with occlusions, different positions, rotations, lightings, colors, etc., and the use of bags. On-training data augmentation was used to further increase the robustness of the model. Additionally, transfer learning was implemented by taking the parameters of a pretrained model used for fruit classification as the new initial parameters of the proposed convolutional network, achieving an increase of the classification accuracy compared with the same model when trained with random initial weights. The final classification accuracy of the network was 98.12% which matches the scores achieved on previous works that performed fruit classification on less challenging datasets. Considering top-3 classification we report an accuracy of 99.95%.
Uncertainty as key element in the analysis of X–ray angiography images
Authors: Bravo A , Vera M , Huérfano Y , Manrique Y , Valbuena O
Published: June 2020

The X-ray angiography images are routinely used to assess the blood vessels. The acquisition procedure considers a medical imaging system which allows obtaining views of the vessel while the blood flows thought them. The X-ray source is influenced on the region to be viewed and then, the projection of the all anatomical structures in the champ of view is shown through an image intensifier. The information of the blood vessel is impacted for the other structures. Additionally, the blood and the contrast product required in the acquisition are not mixed homogeneously, producing artifacts in the images. Finally, the noise is also an impact factor in the quality of the angiography images. In the coronary vessel case, the branches of the network are superposed. In this paper, an enhancement procedure to diminish the uncertainty associated to X-ray angiography images is reported. The relation between two versions of the angiograms is determined using a fuzzy connector considering that this relation diminishes the images intrinsic uncertainty. These versions correspond with images filtered with low-pass and high-pass image filters, respectively. The technique is tested with images of the coronary and kidney vessels. The qualitative results show a good enhanced of the angiography images.
FAZIA: a new performing detector for charged particles
Authors: Barlini S , Bini M , Buccola A , Camaiani A , Casini G , Ciampi C , Frosin C , Ottanelli P , Pasquali G , Piantelli S , Poggi G , Stefanini A A , Valdré S , Bonnet E , Borderie B , Bougault R , Chibli A , Cicerchia M , Cinausero M , Dueñas J A , Fabris D , Frankland J , Gruyer D , Henri M , Kordyasz A , Kozik T , LeNeindre N , Lombardo I , Lopez O , Mantovani G , Marchi T , Quicray J , Upadhyaya S , Verde G , Vient E , Vigilante M
Published: June 2020

The FAZIA apparatus is a new detector designed for the Fermi energy domain for charged particles based on three stages telescopes: Silicon detector (300 μm thick), Silicon detector (500 μm thick) and CsI(Tl) (10 cm). Using the ΔE-E technique and the Pulse Shape Analysis (PSA) it permits the charge and mass discrimination up to more than Z=20. In the following, some details about the FAZIA detectors and electronics, their performance and the frst experimental campaigns already performed will be discussed.
Searching for light dark matter at fixed target experiments
Authors: Bondi Mariangela
Published: June 2020

Nowadays deciphering the fundamental nature of dark matter is one of the foremost open questions in fundamental science. In the last years the dark matter experimental program is primarily focused on weakly-interacting massive particles (WIMPs), but in the recent years many innovative dark matter candidates have emerged. One of the most viable models takes into account DM particles in MeV-GeV mass range that are completely neutral under Standard Model forces, but interact through a new force. Small-scale fixed-target experiments at accelerators have unique sensitivities to fully explore these models. Indeed, accelerator experiments can both produce and detect new particles, such as dark matter and the particles mediating new interactions. This article reviews the various experimental techniques to search for light dark matter, i.e. beam dump, missing mass/energy, and visible mediator search experiments.
MRPC Telescope Simulation for the Extreme Energy Events Experiment
Authors: Mandaglio G. , Abbrescia M. , Avanzini C. , Baldini L. , Baldini Ferroli R. , Batignani G. , Battaglieri M. , Boi S. , Bossini E. , Carnesecchi F. , Cicalò C. , Cifarelli L. , Coccetti F. , Coccia E. , Corvaglia A. , De Gruttola D. , De Pasquale S. , Fabbri F. , Fulci A. , Galante L. , Galeotti P. , Garbini M. , Gemme G. , Gnesi I. , Grazzi S. , Hatzifotiadou D. , La Rocca P. , Liu Z. , Maron G. , Mazziotta M. N. , Mulliri A. , Nania R. , Noferini F. , Nozzoli F. , Palmonari F. , Panareo M. , Panetta M. P. , Paoletti R. , Pellegrino C. , Perasso L. , Pinto C. , Piragino G. , Pisano S. , Riggi F. , Righini G. , Ripoli C. , Rizzi M. , Sartorelli G. , Scapparone E. , Schioppa M. , Scribano A. , Selvi M. , Serri G. , Squarcia S , Taiuti M. , Terreni G. , Trifirò A. , Trimarchi M. , Triolo A.S. , Vistoli C. , Votano L. , Williams M. C. S. , Zichichi A. , Zuyeuski R.
Published: June 2020

A simulation tool based on GEMC framework to describe the MRPC telescope of the Extreme Energy Events (EEE) Project is presented. The EEE experiment is mainly devoted to the study of the secondary cosmic muons by using MRPC telescope distributed in high schools and research centres in Italy and at CERN. This takes into account the muon interactions with EEE telescopes and the structures surrounding the experimental apparata; it consists of a dedicated event generator producing realistic muon distribution and a detailed geometry description of the detector. Microscopic behaviour of MRPCs has been included to produce experimental-like data. A method to estimate the chamber efficiency directly from data has been implemented and tested by comparing the experimental and simulated polar angle distribution of muons.
Imbalanced transfer of trade-related air pollution mortality in China
Authors: Zhao Hongyan , Liu Yang , Geng Guannan , Li Xin , He Wenjie , Chen Xiaoting , He Kebin , Zhang Qiang
Published: June 2020

Revealing the determinants and associated impacts of the transboundary pollution caused by trade is a critical issue when promoting the joint control among regions. This interdisciplinary study utilizes physical, economic and epidemiological methods to explore the anthropogenic PM2.5 related mortality driven by interprovincial trade within China and its determinants. The results showed that 68% of the mortality flow in China was from the central and north plain area, with 29% occurring within these regions and 39% flowing to other eastern and western provinces. The high death intensity resulting from higher exports of heavily polluted agricultural and heavy industry products dominated the trade surplus of PM2.5 mortality for the central and northern plains of China; these bring an imbalanced economic return for these regions, with only 43% of the value added generated in interprovincial trade being retained in these regions. Our study provides a more comprehensive picture of how atmospheric pollution deaths were caused by domestic trade within China, which may facilitate the multilateral pollution mitigation actions from an environmentally economic balanced perspective.
Increasing the Production of L-asparaginase from Bacillus substilis RRM-1 by UV-Mutation
Authors: Prihanto A A , Muyasyaroh H , Puspita F I
Published: June 2020

L-asparaginase is an enzyme that can hydrolyze L-asparagine to L-glutamic acid and ammonia. This enzyme has essential usage for food and health. Bacillus subtilis RRM-1 produces enzyme L-asparaginase, yet the production of L-asparaginase from B. substilis RRM-1 still relatively low. Hence, the effort to increase the production of the enzyme is needed. For increasing the enzyme production, the bacteria were mutated using UV rays to increase the production of L-asparaginase. UV rays (15 watts) were exposed to bacteria with a distance of 15 cm and a contact duration of 30, 60, 90, 120 min. Survival rates of bacteria were calculated, and mutant bacteria were analyzed for their ability to produce L-asparaginase. The mutants examined were taken from a 120-minute mutation treatment, which produced six isolates (UV1, UV2, UV3, UV4, UV5, UV6). Mutant UV1 and UV6 showed better results in producing the enzyme L-asparaginase. Moreover, UV6 produces an activity of 8.02 ± 1.22 U/ml. UV6 production is higher than that of B. subtilis RM-1 wild type (3.18 ± 0.65 U/ml). Mutations with UV can produce mutants that can increase enzyme production by three times.
Biological aspect and dynamic population of fringescale sardine (Sardinella fimbriata: Valenciennes, 1847) in Prigi waters Trenggalek, East Java, Indonesia
Authors: Bintoro G , Lelono T D , Deafatmi L
Published: June 2020

Fringescale sardine (Sardinella fimbriata) is one of important species caught in Prigi waters, Trenggalek, East Java. The existence of fringescale sardine as marine fisheries commodity plays an important role in Prigi fisheries community. This research was conducted in Prigi waters from December 2018 to July 2019 aimed to determine the biological aspects, to illustrate some dynamic population parameters, and to identify food composition. This study applied a descriptive method and random sampling for data collection. There were 1,375 fish have been assessed with total length (TL) ranging from 10 cm to 20.4 cm. Results indicated that growth patterns of the fish was negative allometric with length weight relationship equation was W = 0.014L2.804. Sex ratio of male and female obtained was 1: 1. The gonad maturity level analysis found that proportion of mature and immature fish was equal. The gonadosomatic index value was ranged from 0.57% to 2.42%. The values of length at first capture and length at first mature were 15.35 cm and 16.07 cm, respectively. The growth rate equation obtained in this study was Lt = 26.75 (1-e0.92 (t+0.178)). Mortality rates, total and fishing were 1.709 and 0.286, respectively, while the exploitation rate was 0.167. Additional assessment showed that the main food of the fringescale sardine was phylum Arthropods with index of preponderance (IP) value was 61.5%. It can be concluded that the fish was a plankton feeder and status of the stock was in over fishing condition.
Flow cytometric analysis of genome size of Oreochromis niloticus and O. aureus and their interspecific hybrid
Authors: Imron I , Robbisalmi A , Gunadi B , Abdurachman M L
Published: June 2020

Srikandi tilapia, a hybrid resulting from an interspecific cross between female Oreochromis niloticus and male O. aureus, has shown advantages in farming performance. It shows higher productivity in high salinity aquaculture environment than that of both parental lines. From genetic point of view, organismal phenotypes, to some extent might be affected by its genome size or cellular DNA content. This study was aimed to identify the genome size of these two species along with their hybrid. 75 individuals representing three groups, namely two parental lines and its hybrid were sampled and measured for their DNA content by flowcytometry. The mean (±SD) DNA content of O. aureus (1.271 ± 0.0022 pg) was higher but was not statistically significantly different (P>0.0175) from that of the O. niloticus (1.261 ± 0.0022 pg). The mean (±SD) DNA content of the hybrid (1.263±0.001) was in between and was not significantly different (P>0.05) from both parental species. Individual variation of DNA content within species was lower than those between species. No significant difference was observed in DNA content between male and female within the respective groups.
Relationship analysis of N/P ratio and phytoplankton abundance in Ranu Pakis using regression approach
Authors: Lusiana E D , Musa M , Mahmudi M , Buwono N R , Utami K P
Published: June 2020

Ranu Pakis is a natural lake that formed by volcanic activity. The lake waters have many benefits including as a source of irrigation, aquaculture, agriculture, and tourism. The activities around Ranu Pakis have the potential to produce organic waste into the waters. High organic waste and nutrients resulted in eutrophication or high abundance of phytoplankton which threatens biodiversity in the lake. Nutrients in the waters consist of N and P. The ratio between N and P affect the composition and abundance of phytoplankton. The purpose of this study was to analyses the relationship between N/P ratios to the abundance of phytoplankton in Ranu Pakis using quintile regression approach. The results of this study indicated that the effect of the N/P ratio was different on various quintile.
Formula optimization of functional beverages from Sargassum sp., Cinnamomum burmannii, and Curcuma xanthorrhiza Roxb with α-Glucosidase inhibitor activity
Authors: Umam N I , Firdaus M
Published: June 2020

Sargassum sp., cinnamon, and C. xanthorrhiza contain high polyphenols, which play an essential role in inhibiting α-glucosidase activity. The purpose of this study was to determine the optimization of the formula by mixing Sargassum sp. extract, cinnamon extract, and C. xanthorrhiza extract as functional beverages of α-glucosidase inhibitors. This research using the Response Surface Method (RSM) and Box-Behnken with a combination of three factors, namely the concentration of Sargassum sp. extract (A), the concentration of cinnamon extract (B), and the concentration of C. xanthorrhiza extract (C). The response variables consisted of total polyphenol (Y1), and percentage inhibition of α-glucosidase (Y2). The optimum formula was followed by UPLC-MS/MS assay. The best formulation for functional beverages is Sargassum sp. 20%, cinnamon 12.773%, and C. xanthorrhiza extract at 18.5% with of total polyphenols (108.834 mgGAE/100mL) and inhibition of α-glucosidase (64.323%).
Characteristics of Aeromonas hydrophila-infected Catfish (Clarias sp.)
Authors: Kartikaningsih H , Yahya  , Rohman F Z , Jaziri A A
Published: June 2020

Catfish production was affected by Aeromonas hydrophila. This study aims to investigate the effect of A. hydrophila infection on catfish (Clarias sp.). Physical properties (SEM and histology), morphology, and organoleptic test. The results of this study reported that the morphology of catfish infected with A. hydrophila had clinical symptoms, such as swelling on stomach and intestines were black on days 5 to 7, in the skin injured on day two and hemorrhagic on day 6-7, the quality of the meat decreased on the day 7. The organoleptic test indicated that the quality of the mucus, texture, and odor was reduced. Furthermore, the results of the histological test reported stretching of the muscle.
Fresh frozen fish consumer behavior: effect of the mix and trust marketing on buying interest, purchase decision and customer satisfaction in E-commerce, silly fish Indonesia
Authors: Abidin Z , Triono L D
Published: June 2020

Increased fishery production and technological developments, triggers online marketing competition in the fisheries sector. The most effective factors that influence buying interest, purchasing decisions, and customer satisfaction in e-commerce Silly Fish Indonesia are essential to increase sales volume. The research purpose was to analyze the effect of some marketing mix, which consists of promotion, product quality, price, and trust in buying interest, purchasing decisions, and customer satisfaction. The method of data analysis uses analysis of Structural Equation Modeling. The distribution of online questionnaires obtained 120 respondents. The results of the study show that promotion, product quality, price, and trust have a positive influence on buying interest, purchasing decisions, and customer satisfaction both directly and indirectly through mediation.
An Index for Evaluation for Urban Bicycle Lanes
Authors: Pesshana G , Romanel C , Novo J
Published: June 2020

Traditionally, the focus of urban transportation design is on motorized vehicles with less attention to green travel alternatives such as cycling. Public policy makers are now trying to increase cycling as a sustainable travel mode due to increasing concerns with respect to environmental pollution, traffic jams and health problems from today’s sedentary way of life. In the city of Rio de Janeiro, Brazil, the first bicycle lanes were built in 1991along the urban seafront for leisure and touristic purposes almost exclusively, but today the city counts on a cycling network of more than 150 kilometres under different conditions of conservation and use by the population. The manner in which this network is designed, built and managed can have a significant effect on the utility and safety of cycling. The primary objective of the current study is to develop a methodology and to propose an evaluation index that could be used as a practical instrument by municipal authorities, transportation planners, traffic engineers and others to determine the quality of bicycle lanes under 14 criteria based on social, technical and environmental aspects. The availability of a such comprehensive index is believed to be a key factor guiding cycle-friendly politics to build more sustainable cities
Living and Comfort Conditions in Heritage Housing: The Inner Courtyard as a Uniting Element in the Cités of Santiago Poniente
Authors: Piedra K , Bustamante W , Schmitt C
Published: June 2020

Heritage buildings represent an essential housing stock that has been available in Santiago de Chile for over a century. However, most of these buildings show sustained deterioration due to lack of maintenance, which creates degrading living conditions for its residents caused by habitability problems. One of these cases is the “cité” typology, which was massively built at the end of the 19th century. The Cité is a group of houses with a continuous facade, with built areas of 50 to 80 m2, connected through a common and private space that provides access to the residences. Currently, the reduced housing area in the city has forced users to occupy the existing courtyards to satisfy their needs. This situation affects interior lighting conditions, thermal control, and air quality. These interventions modify the architectural design into units with only one facade exposed to the exterior environment. Nevertheless, adaptation strategies have become more and more complex due to restrictions on heritage building regulations, which generally do not meet thermal performance or natural light availability. Among the environmental conditions, indoor air quality is a relevant factor and could be related to the progressive deterioration of the residence’s interior conditions, and the health of its residents.The methodology considers data compilation on existing units and energy performance simulations of both original and existing units. Software such as DesignBuilder and a wind tunnel were used to simulate different habitability variables. Results confirm that in the majority of cases studied, indoor air quality is not bad due to air infiltrations as a product of modifications, spontaneous extensions, and building deterioration through the years. However, they show an inadequate thermal performance that does not meet the minimal comfort conditions. Nevertheless, the simulations on original units demonstrate a positive impact of courtyards for reaching ventilation and natural lighting standards. Measurements on-site have shown a beneficial effect from using vegetation in ventilated covered courtyards.
Heating and Cooling Energy Savings of a Proposed Variable Thermal Resistance Envelope (Dynamic EIFS) in Office Buildings
Authors: Palacios I , Bobadilla A
Published: June 2020

This paper evaluates potential heating and cooling energy savings of a theoretical building envelope system capable of modifying its thermal resistance according to the changing weather conditions. A Dynamic External Insulation Finishing System (D-EIFS) theoretical model is proposed based on recent research on dynamic building envelope technologies, which suggest that this functionality will be fully available in the near future. We also develop and apply a unique simulation technique for using commercially available BPS software to assess the heating and cooling energy savings potential of a D-EIFS for office buildings. A performance comparison of the proposed D-EIFS with the most efficient EIFS for the same office building shows a heating and cooling energy savings of up to 26% in the summer season in a temperate climate.
Study of Social Organization for the Use of Firewood Heating in Zones Where Polluting Material is Generated in the City of Temuco, Araucanía Region, Chile
Authors: Alvarez E
Published: June 2020

Temuco, capital of the Araucanía Region of Chile, presents the highest indices of pollution by smoke from wood-burning heating stoves in the country, specifically during the southern winter. Firewood combustion is the cheapest heating fuel available to the population of Temuco, and has resulted in considerable contamination in the city. There has been an large increase in the city’s population, while the winter months from April to September have been growing colder. The problem affects the whole population, and especially children and the elderly. The pollution indices present serious levels. The evening and night are the worst times to be outside, due to both poor visibility and the toxicity of the environment. This situation is a social problem which has not been fully investigated. More seriously still, the people of Temuco do not display particular concern about their collective health or about protecting the environment from the smoke produced by wood-burning stoves. In view of this serious problem, the present article proposes a strategic design for information and social organisation by sectors in the city’s residential districts, in order to generate awareness and communication in the community. The strategic guidelines are drawn with special emphasis on visual communication, in both printed and digital format, in order to organise social groups of people motivated to solve the pollution problem. The central object of this proposal is to offer a strategic model able to generate collective awareness to support and help the city’s housing estates and residential zones. Connection between community members, empathy and social assistance will be basic aspects for the functioning of the strategy when it is applied. Finally the proposal contemplates social organisation in pursuit of the common good: protecting the local environment, improving people’s quality of life, and promoting social coexistence in housing estates and communities affected by the problem of pollution by smoke from wood-burning stoves.
Alberto Curamil and the Goldman Prize: Discussion of Cultural Sustainability in the Region of La Araucanía
Authors: Leal F , Navarrete C
Published: June 2020

The following article discusses the recent winner of the Goldman prize, Mapuche leader Alberto Curamil, as a case in the struggle for cultural sustainability in the Region of La Araucanía, mainly in his role as an activist in the defense of Mapuche territory and culture. This important international environmental award was conferred on Curamil for uniting Chileans in preventing the construction of two hydroelectric projects and protecting a river sacred to the Mapuche people, overcoming violent persecution and attacks against him in this activity. This makes it possible to problematize different aspects of cultural sustainability that are key in the region, in particular the issue that arises between the progress of industry and the ancestrality of indigenous peoples. Thus, it is interesting to discuss from this case how these two views can be harmonized in order to achieve cultural sustainability, bearing in mind the intercultural nature of the IX Region. Finally, this communication seeks to analyze the role of the Chilean State and its actions concerning the practices of cultural sustainability like those led by Curamil.
Universal Accessibility in UC Temuco
Authors: Simian M P
Published: June 2020

In present-day societies, people’s life expectancy is increasing thanks to medical and technological progress; therefore, the number of disable citizens is also increasing. An accessible design is one that is functionally and aesthetically adapted to its users and their real and personalized needs. Accessible spaces are those that allow everyone, particularly people with limited physical or sensorial capacity, to enjoy all its elements in the appropriate conditions of comfort, safety and autonomy. By incorporating this characteristic into the design of our products, buildings and into everything that surrounds us, we improve the comfort and quality of the articles and services we offer the public without increasing their cost, all thanks to small details that benefit the largest number of people. Each country has its own legislation regarding accessibility. In Chile the first Integration Social Law N°19.284 is due to 1994. One of the biggest difficulties for disable persons to move around cities and buildings is the lack of ramps in public buildings. Although the Supreme Decree 201/98 establishes that all building, public or private, with occupation for more than 50 people should have an access for disabled, although there are many places in this country that today do not validate this requirement. In the year 2010 the Law 20.422 improved the standards regulating the minimal general guidelines based on the accessibility requirements for improving especially bathrooms, hygiene services for public-use buildings and changing rooms. This document presents a local case of study. The Catholic University of Temuco (12.000 students) is located in the south of Chile (Araucania Region). This region is the poorest in the country. Since 2012 the University is part of the University Inclusion Network. Consequently, since then, educational buildings and public spaces have been improving accessibility and are now better prepared for the challenge of welcoming disabled students.
Thermal Insulating Panels Based on Recycled Tetra-Pak® Packaging Materials
Authors: Olfos L , Valdes F , Sarabia G , Barros P
Published: June 2020

This article introduces a novel approach for repurposing Tetra-Pak® residues as raw materials for the manufacturing of insulating panels for dwelling frameworks. This new development is intended as affordable insulation systems for emergency and permanent social housing. The three proposed panels were designed, manufactured, and tested, and showed similar or better thermal properties than traditional insulators available in the local market. To benchmark the design embodiments, custom apparatuses and dedicated sensing instruments were also developed.
Mortar Based on Biomass Ashes from Araucanía Region
Authors: Soto O , Goméz N , Manzur C , González A
Published: June 2020

The COMASA S.A. power plant is located near Temuco and burns a high amount of residual biomass produced in the Araucanía region. However, the main problem associated with this plant is the transportation and disposal of fly ash (9 tons per week), a residue generated during the combustion of Boiler I. Currently, fly ashes from Boiler I are transported more than 200 km south, increasing transportation and final disposal costs. In this study, the development of a mortar based on fly ash from the combustion of biomass from COMASA S.A. was analysed at a pre-feasibility level. The experimental procedure consisted of (i) the physicochemical characterization of biomass fly ash, (ii) obtaining different test specimens (mortars) via the addition of different proportions of fly ash (10-35%) to cement, and (iii) obtaining the best specimen by analysing the requirements of mortars for construction purposes (Chilean Standard NCh 1037). The test specimens were subjected to determination of apparent density, compression resistance, water absorption capacity and moisture content. The laboratory results showed that the mortar obtained with the addition of 20% of fly ash has similar physical characteristics to mortars used for building blocks, proving capable of resisting up to 20 MPa. To analyse the viability of the production of construction blocks based on best specimen, market, technical and economic-financial studies were carried out, considering the reuse of at least 60% of the fly ash generated per year. The study concluded that the project was viable, evidencing the potential use of this residue for the manufacture of low-cost blocks, while minimizing the cost associated with residue handling.
Increase of Mechanical and Thermic Performance of Polymers with Renewable-Base Nanomaterials to Develop Composite for Fiber Reinforced Polymers Industry
Authors: Hunter R , Valenzuela P , Hidalgo P
Published: June 2020

The objective of this research was to evaluate mechanical and thermal performance of a commercial adhesive with the incorporation of renewable-based nanomaterials. Renewable-based CNTs (carbon nanotubes) were synthesized using microwave irradiation of pyrolyzed oat hulls biochar and ferrocene as catalyst. CNTs were mixed with epoxy adhesive and TEPA (tetraethylene pentamine) which were used as curing agents. In the evaluation of mechanical and thermal properties of the composites studied, the samples contained between 0.02-0.1 wt% of CNTs. All composites were cured during 2 hours at 60°C. Mechanical properties (tensile strength and modulus) were tested in a Universal Testing Machine and were evaluated according to ASTM D638. Thermal properties were evaluated using a Thermogravimetric Analyzer. Of the results obtained an improvement of mechanical and thermal properties were observed. Thus, the incorporation of renewable-based CNTs can be a suitable alternative both to reduce fiber reinforced polymer manufacturing costs and in the valorisation of waste biomass
Determination of Dwelling Typologies in Chile to Define Energy Efficiency Programmes
Authors: Galbiati J , Sepúlveda H , Videla J.T. , Hermosilla P
Published: June 2020

The Ministry of Housing and Urbanism of Chile (MINVU) has led the implementation of thermal conditioning requirements in dwellings (2000, 2007) as well as the Dwellings Energy Rating System (2012). To design improvements to both programmes, MINVU required a statistical analysis identifying the statistical distribution of the different parameters that influence the energy demand of the dwellings, as well as typologies and their distribution, both at the national level as well as that of the 9 thermal zones. A series of statistical analyses was developed for this purpose; mainly a Conglomerates Analysis, using specifically the hierarchic agglomerative method. This method was applied to detached dwellings, Semi-detached or Terraced dwellings and Apartment segments. So as to obtain more stable frequencies, as well as estimate standard deviations and confidence intervals, 200 random samples were obtained for each segment. The main result was the definition of 13 dwelling typologies in Chile, their respective distribution at the national and thermal zones levels, as well as the representation of the parameters that compose these typologies and influence energy demands. Finally, an analysis was carried out, based on secondary images of dwellings representing their respective typologies; this allowed complementing and correcting the typologies’ definition where it should be necessary. A second study is being carried out at the time of closing this document -using those results- this shall allow to establish the energy demand of dwellings built in Chile before 2018, by typology, thermal zone and thermal regulations stage, so that Minvu may quantitatively define the energy demand baseline, consolidate measurement metrics, and refine long-term improvement objectives.
Experimental Comparison of Passive Heating/Cooling Space in Lightweight Buildings with Potential Application in Mining Camps
Authors: Villalobos I , De Gracia A , Chafer M , Cabeza L F , Ushak S
Published: June 2020

The total energy consumption in a house in Chile includes 30% of heating expenses, increasing to 60% in the winter period. The current energy source are fossil fuels, which can be replaced by the sun, with an efficient implementation of the use of PCM for passive cooling/heating space from solar radiation, benefiting the environment. In the north of Chile there is a solar radiation index of approximately 2750 kWh·m−2, low cloudiness and low precipitation rates, indicating an important source of energy and great opportunity for improvement in the use and management of energy resources. Moreover, mining camps present in large numbers in the northern zone require a lot of energy to cool and heat the space. This research shows the thermal behavior in summer and winter of two lightweight constructions, similar to the type used in mining camps, with dimensions of 2.5 × 2.5 × 2.5 m at pilot scale installed at the University of Antofagasta, Chile. One of these modules contains PCM on the inside of the walls and ceiling, while the other does not, to analyze the effect of PCM by comparison. The results of this work show that in winter (August) the application of PCM favors the permanence within the thermal comfort zone, with a difference of 5°C. In summer there is an opposite effect (January), experiencing a higher temperature increase inside the container with PCM, with a difference of 4°C. According to the constructive characteristics, properties and quantity of PCM used, and the effect of solar radiation on the structure and environmental conditions, there are benefits in energy saving and efficiency in the winter period, while summer shows results that enhance the study and analysis of the applied technology to solve the thermal behavior shown in this season.
Alfândega Square: The Place of Plurality
Authors: Volpatto C P , Edelweiss R K
Published: June 2020

The present article is based upon a master’s degree Dissertation entitled “Alfândega Square: a place of places”. Subject to the current work is the Alfândega square, located in the historic portion of downtown Porto Alegre, the capital of the Federal State Rio Grande do Sul. The square is composed by distinct parts: Lugar de Memória (the place of memories), Lugar de Entorno (the place of ambience), Lugar de Pluralidade (the place of plurality) and Lugar de Evento (the place of events). With these different places highlighting the various dimensions of public places in metropolises, using the Alfândega square as the study subject raises some relevant questions about how much a public space can change throughout its existence. It can be affirmed that in this mosaic of social representations, vicinal territories and symbols comprise an important locus for the analysis of the urban space, since it presents itself for social forms’ multiple spaces of material survival and social coexistence. For this reason, the study of the Alfândega square is also an investigation about contemporary urban phenomena and their multiple and emerging social practices that are modified by the influence of external factors in the city. This article has its emphasis on the place of plurality, remembering the profile of regular visitors in the past and comparing it with present-day users. The non-participating observation methodology was used to analyse regular visitors of this public space. Visits to the square where carried out in different periods of time during the two years of study. As a result of these visits, a series of territorial maps were created, depicting the territories of the regular to the square.
Social Perception of Living Walls in Quito: A Study of Four Vertical Gardens
Authors: Maron A , Ramirez F
Published: June 2020

As part of a transdisciplinary study on the benefits of vertical gardens in Quito (Ecuador), social research was carried out to determine people’s perceptions and level of understanding of living walls. The four gardens studied were on the campus of the Pontifical Catholic University of Ecuador (semi-public), in the San Blas Plaza (public), in the Governmental Financial Platform (semi-public), and in the private offices of an architecture firm (private). The research was organized into two primary phases; the first involved carrying out observations of each of the four vertical gardens. The observations led to the characterization of the immediate surroundings of the gardens, an understanding of accessibility (particularly for people with disabilities and security-related limitations), as well as of the number of people who passed through the space and the type of interactions they had with the garden. During the second phase, a total of 57 interviews were carried out with people in the areas surrounding each of the vertical gardens. The interviews identified basic demographic information about the respondents, how they define vertical gardens, the type, and frequency of their interactions with the specific garden of study, and their perceptions of the benefits and drawbacks of vertical gardens. The information from the interviews was processed to identify key trends related to each garden, as well as identify trends across the four gardens. The results revealed varying levels of understanding of vertical gardens, the influence of esthetics on people’s perceptions, and finally ideas around the benefits and drawbacks of vertical gardens. The conclusions demonstrated a gap between social perceptions of vertical gardens, particularly in public spaces, and the gardens’ potential ecological and air quality contributions to the city.
Investigating the Walkability Index of a Commercial City Center Using Simulation and Surveys: The Juiz de Fora Case Study
Authors: Carvalho B , Barbosa G , Drach P
Published: June 2020

Although the positive impacts of the urban experience are perceptible when the population occupies public spaces, it is notable that the pedestrian loses more space to motorized transportation every day. The cities are often adapted or even built for the circulation of automotive, which increasingly decreases the walkability in urban areas. However, several studies note that the vitality of a path directly benefits local commerce and safety. This argument encourages the implementation of pedestrian paths and mechanisms that benefit people’s permanence in urban centers. Considering these issues, this article aims to investigate the walkability of the commercial center of Juiz de Fora (MG), a neighborhood that has a peculiar morphology with commercial galleries and that has been encouraged in recent decades to create pedestrian paths. This research method comprises three main steps: computational simulations, interviews and assessment of the Walkability Index (ITDP, 2018). The simulation experiments consist of the construction of a spatial syntax, through the Depthmap program, which processes the path possibilities within the studied region. Its use includes the analysis of network passages configured by commercial galleries, which have an important function for mobility. The interviews were conducted, within the sample space, with questions based on important criteria for the classification of a livable city. Finally, the Walkability Index, based on six criteria (i.e., sidewalk, mobility, attraction, road safety, public safety and the environment), was assessed. Based on the results, there is evidence that the commercial center of Juiz de Fora provides essential characteristics for the quality of mobility for pedestrians, highlighting the importance of the urban form for walkability in commercial centers. Future studies considering other urban centers could benefit from the insights gained from this study as well by applying the proposed research method.