Different Types Of Elements Research Articles

Identification Model of Traditional Village Cultural Landscape Elements and Its Application from the Perspective of Living Heritage—A Case Study of Chentian Village in Wuhan

At present, there are limitations in the cognition of the elements of traditional village cultural landscapes, less excavation of the elements of production-type cultural landscapes, little attention to the layering of cultural landscapes in different periods and the correlation between the elements of different types of cultural landscapes, and insufficient research on the living continuity of traditional village cultural landscapes. In the context of rural cultural revitalization, it is necessary to explore strategies for the conservation and development of traditional village cultural landscapes from the perspective of living heritage. By interpreting the core connotation of the concepts of living heritage and cultural landscape, a model of traditional village cultural landscape elements and a framework for the identification of living elements are constructed. On the above basis, Chentian Village in Wuhan is taken as an example to identify its living cultural landscape elements, and to analyze the evolution of its cultural landscape elements from the dimension of “time-function”. In Chentian Village, a total of seventeen cultural landscapes were identified. Of these, ten were cultural landscapes with functional continuity and living heritage characteristics; three were cultural landscapes whose existing functions have changed significantly from their initial functions; and four were cultural landscapes that were inactive and have lost their original functions. Finally, this study proposes corresponding protection and development strategies for living heritage and non-living heritage of cultural landscapes.

تقدير المعادن الثقيلة في بعض أنواع مختلفة الكعك المجمعة من أسواق مدينة البيضاء – ليبيا

Heavy metals are chemical elements with high density and atomic weight. Despite their widespread use in various industries and applications, they pose significant risks to the environment and public health if not handled properly. This study was conducted to estimate the concentration of some different elements in different types of cakes, where cake samples were collected from different shops from Al-Bayda city, the study dealt with six types of cakes. Flame photometer was used to estimate sodium and potassium salts and spectrophotometer to estimate heavy elements. The samples were digested using the digestion method using HNO1 and HCl and heating until the brown oxides evaporate and we get half the amount. The results showed that the concentration of sodium, chromium, iron and copper is below the permissible limits and the concentration of potassium is higher than the permissible limits and the results also showed that the collected cake samples do not contain lead and a discrepancy was observed .The potassium concentration ranged from (541. 50 to 763.25), sodium concentration ranges from (1.34 to 3.52), iron concentration ranges from (1.72 to 7.16), copper concentration ranges from (44.36 to 67.62), and chromium concentration ranges from (0 to 0.25). The study could be expanded to include other types of cakes, such as filled cakes to provide a more comprehensive picture of heavy metal contamination in these products. More heavy metals, such as mercury, arsenic, and cadmium, could be analyzed to more accurately assess health risks. Keywords: Heavy metals, Cakes types, market and Al-Bayda – Libya.

Rice sample preparation method for ICP-MS and CV-AFS analysis: Elemental levels and estimated intakes

Eight sample digestion procedures were compared to determine 41 elements in rice samples by ICP-MS and CV-AFS. Analytical methods were evaluated using certified rice flour reference material (NIST 1568b) and recovery experiments. The microwave-assisted digestion of 0.5 g rice sample and reagent mixture of 2 mL HNO3, 0.5 mL H2O2, and 0.5 mL deionized water yielded the best recovery for all elements ranging from 90 to 120% at three different levels, bias% within 10%, and precision (coefficient of variation percent, CV% intra- and inter-day) below 15%. The best analytical method was applied to the elemental determination in nine types of rice available on the Italian market. Daily or weekly rice consumption meets the nutritional and safety requirements of EFSA and WHO. The present study allows extensive and detailed knowledge of the content of essential and non-essential/toxic elements in different types of rice produced or packaged in Italy.

Degradation Mechanisms of Mortar and Plaster Layers.

This article presents a case of complex investigation of defects of lime mortar and plaster that have been developing over a period of 48 years in a house in Prague and are strongly influenced by thermal and salt crystallization cycles. The aim of this research was to describe the degradation phenomena of mortars and plasters observed on a narrowly limited part of the building, combining structural elements of different types and ages and to explain the mechanisms of their formation and development. The geometric characteristics of the defects were determined by non-destructive methods, especially optical interference moiré, laser profilometry, photogrammetry, and infrared thermography. Material data were determined on samples by electron microscopy, ion exchange chromatography, and direct moisture content measurements. The results supported the hypothesis of the increase in the deformation of large buckles of detached plasters by the mechanism of buckling caused by loading of the edges with compression generated by volume changes. Direct loading of the boundary surfaces causes the formation of bulges in the confined areas. This study shows the importance of failure analysis of real structures to gain knowledge about the behavior of structures and materials under long-term service conditions.

Healthcare experiences of pregnant and postnatal women and healthcare professionals when facing child protection in the perinatal period: A systematic review and Critical Interpretative Synthesis.

The perinatal period is known as time of transition and anticipation. For women with social risk factors, child protection services may become involved during the perinatal period and this might complicate their interactions with healthcare providers. To systematically review and synthesise the existing qualitative evidence of healthcare experiences of women and healthcare professionals during the perinatal period while facing child protection involvement. A systematic search of databases (Web of Science, MEDLINE, EMBASE, PsychINFO, CINAHL, ASSIA, MIDIRS, Social Policy and Practice and Global Health) was carried out in January 2023, and updated in February 2024. Quality of studies was assessed using the Critical Appraisal Skills Programme. A Critical Interpretative Synthesis was used alongside the PRISMA reporting guideline. A total of 41 studies were included in this qualitative evidence synthesis. We identified three types of healthcare interactions: Relational care, Surveillance and Avoidance. Healthcare interactions can fluctuate between these types, and elements of different types can coexist simultaneously, indicating the complexity and reciprocal nature of healthcare interactions during the perinatal period when child protection processes are at play. Our findings provide a novel interpretation of the reciprocal interactions in healthcare encounters when child protection agencies are involved. Trust and transparency are key to facilitate relational care. Secure and appropriate information-sharing between agencies and professionals is required to strengthen healthcare systems. Healthcare professionals should have access to relevant training and supervision in order to confidently yet sensitively safeguard women and babies, while upholding principles of trauma-informed care. In addition, systemic racism in child protection processes exacerbate healthcare inequalities and has to be urgently addressed. Providing a clear framework of mutual expectations between families and healthcare professionals can increase engagement, trust and accountability and advance equity.

Short‐Term Sea Fog Area Forecast: A New Data Set and Deep Learning Approach

AbstractPrompt and precise forecast of sea fog regions ensures maritime navigational safety. This paper establishes a prompt and precise forecast of sea fog regions that ensure maritime navigational safety. This paper establishes a multivariable sea fog forecast (MV‐SFF) data set and proposes a deep learning‐based forecast method named rich‐element aggregated (REA) for short‐term forecasts. The MV‐SFF data set contains 122 sea fog events from 2010 to 2020. Each event in the MV‐SFF data set includes meteorological variables from reanalysis data and geostationary ocean color imager satellite images captured hourly on the day of the sea fog occurrence. This data set aims to comprehensively utilize meteorological elements and remote sensing observations to predict the spatial changes of sea fog areas in the next 7 hours. The proposed REA model can extract and integrate features from historical meteorological elements of different types, times, and spatial locations. In addition, REA utilizes a position‐aware edge detection mechanism to locate the exact position of sea fog. We perform a seven‐hour ahead forecast starting from 09:16 local time and show promising forecasting results, which demonstrate the fog area forecast ability of our model. Compared with existing advanced deep learning networks, the REA model is superior in performance and stability.

The transcription factor PAX5 activates human LINE1 retrotransposons to induce cellular senescence

As a hallmark of senescent cells, the derepression of Long Interspersed Elements 1 (LINE1) transcription results in accumulated LINE1 cDNA, which triggers the secretion of the senescence-associated secretory phenotype (SASP) and paracrine senescence in a cGAS-STING pathway-dependent manner. However, transcription factors that govern senescence-associated LINE1 reactivation remain ill-defined. Here, we predict several transcription factors that bind to human LINE1 elements to regulate their transcription by analyzing the conserved binding motifs in the 5’-untranslated regions (UTR) of the commonly upregulated LINE1 elements in different types of senescent cells. Further analysis reveals that PAX5 directly binds to LINE1 5’-UTR and the binding is enhanced in senescent cells. The enrichment of PAX5 at the 5’-UTR promotes cellular senescence and SASP by activating LINE1. We also demonstrate that the longevity gene SIRT6 suppresses PAX5 transcription by directly binding to the PAX5 promoter, and overexpressing PAX5 abrogates the suppressive effect of SIRT6 on stress-dependent cellular senescence. Our work suggests that PAX5 could serve as a potential target for drug development aiming to suppress LINE1 activation and treat senescence-associated diseases.

Structure–spectrum relationship in the calculated Raman spectra of silicates

AbstractSilicate minerals have a rich structural variety consisting of silicon oxide clusters or networks of any dimensionality interdispersed with different types of elements, which is reflected in marked changes in the Raman spectra. Understanding how the changes in the Raman spectra are correlated with the atomic structure would be highly desirable for fast material identification and analysis. Extracting such trends from experimental spectra can be difficult owing to the uncertainties in the structural details of the samples and in ensuring consistency between measurements from different sources. Simulated spectra, however, avoid these problems, making them a good candidate for systematic studies. Here, we study the correlation between the structure and Raman spectral features of 179 silicates derived from a database of Raman spectra simulated using first‐principles calculations. We investigate the spectral similarities with a specific emphasis on materials containing isolated 0D clusters in nesosilicate (SiO4), sorosilicate (Si2O7), and cyclosilicate (Si3O9 and Si4O12) configurations. While trends identified in the previous reports can be confirmed, we find that the variations within each group of similar structural motifs tend to be larger than the changes across groups, and therefore, developing a reliable automated classification algorithm is likely to be challenging.

Analysis of the influence of mechanical properties of cementitious composites using submerged arc welding (SAW) slag recycled aggregate

Concern about the environment and the scarcity of natural resources has led to the search for more sustainable alternatives that minimize the environmental impact of all segments of society. Solid waste recycling has been presented as a good alternative to reduce the impacts generated by the disorderly use of raw materials and the reduction of disposal areas, caused by the large volume of waste disposal generated throughout the year throughout the world. In this context, waste from industries in Brazil is included, especially submerged arc welding (SAW) slag. Waste from these activities is generally solid, with dense materials and variable characteristics in terms of their chemical composition, as they contain different types of elements with a specific function as a load element. These characteristics often present an obstacle to being reused in new materials (flows). Among the various waste generated by various industries, we can mention submerged arc welding (SAW) slag, as being one of the greatest potentials for use, due to often having knowledge of its basic characteristics and properties and its lower degree of contamination by other materials, when compared to other waste, such as construction waste. The objective of this research is to evaluate the mechanical performance characteristics of cementitious matrices made with submerged arc welding (SAW) slag residue and their possible use on a large scale. Cementitious matrices for mortars were manufactured by replacing 0%, 25%, 50% and 75% of the natural fine aggregate with submerged arc welding (SAW) slag residue and a water/cement ratio of 0.48. Through the compressive and tensile strength test, it was observed after 28 days that the cement matrices with replacements obtained increases in the mechanical properties of compressive and tensile strength, compared to the reference cement matrix.

Do You Know What You Drink? Comparative Research on the Contents of Radioisotopes and Heavy Metals in Different Types of Tea from Various Parts of the World.

The aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40K, 137Cs, 226Ra, 210Pb and 228Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations [mg/kg] of the studied elements (Fe, Cr, Cu, Mo, Al, Mn, Ni, P, V, Cd and Pb) were determined using a microwave-induced plasma optical emission spectrometer (MIP-OES). The results presented here will help to expand the database of heavy metals and radioactivity in teas. With regard to the potential health risk, the percentage of leaching of individual elements in different types of tea infusions was determined, and the assessment of the consumption risk was estimated. Since the calculated exposure factors, namely the HQ (Hazard Quotient) and THQ (Target Hazard Quotient), do not exceed critical levels, teas can still be considered health-beneficial products (most of the radionuclides as well as elements remain in the leaves (65-80%) after brewing).

Directions for modifying the artificial bee colony algorithm to optimize control parameters for complex systems

In recent years, bioinspired algorithms based on the use of a population approach and a probabilistic search strategy have become especially popular among researchers involved in multidimensional and multicriteria optimization. Such algorithms are based on the principles of cooperative behavior of a decentralized self-organizing colony of living organisms (bees, ants, birds, etc.) to achieve certain goals (for example, to meet nutritional needs). However, their practical application encounters a number of difficulties leading to a decrease in convergence. This article discusses the possibility of modifying the artificial bee colony algorithm by using a hybridization strategy with various data mining methods. One of these difficulties is the lack of a reasonable approach to determining initial search positions. As a solution, it is proposed to divide the population into clusters, the centers of which will be the initial positions. The need for interaction between individuals makes it advisable to use fuzzy clustering, which allows the formation of intersecting clusters. Another difficulty is associated with the choice of “free” parameters, for which the authors have not developed recommendations for choosing their optimal values. To solve this problem, it is proposed to use the idea of coevolution, which consists in the parallel launch of several interacting subpopulations, for each of which different “settings” are applied. The proposed algorithm is applicable to multidimensional optimization tasks, in which it is necessary to find such a combination of different types of elements belonging to some “large” population that will ensure the achievement of the maximum effect under given restrictions. Examples of such tasks are determining the species and quantitative composition of plants to form the terrestrial ecosystem of a carbon farm or mass recruiting, which consists of selecting a large number of personnel for the same positions.

Oncolytic Virotherapy: A New Paradigm in Cancer Immunotherapy.

Oncolytic viruses (OVs) are emerging as potential treatment options for cancer. Natural and genetically engineered viruses exhibit various antitumor mechanisms. OVs act by direct cytolysis, the potentiation of the immune system through antigen release, and the activation of inflammatory responses or indirectly by interference with different types of elements in the tumor microenvironment, modification of energy metabolism in tumor cells, and antiangiogenic action. The action of OVs is pleiotropic, and they show varied interactions with the host and tumor cells. An important impediment in oncolytic virotherapy is the journey of the virus into the tumor cells and the possibility of its binding to different biological and nonbiological vectors. OVs have been demonstrated to eliminate cancer cells that are resistant to standard treatments in many clinical trials for various cancers (melanoma, lung, and hepatic); however, there are several elements of resistance to the action of viruses per se. Therefore, it is necessary to evaluate the combination of OVs with other standard treatment modalities, such as chemotherapy, immunotherapy, targeted therapies, and cellular therapies, to increase the response rate. This review provides a comprehensive update on OVs, their use in oncolytic virotherapy, and the future prospects of this therapy alongside the standard therapies currently used in cancer treatment.

Characteristics and performance of layered two-dimensional materials under doping engineering.

In recent years, doping engineering, which is widely studied in theoretical and experimental research, is an effective means to regulate the crystal structure and physical properties of two-dimensional materials and expand their application potential. Based on different types of element dopings, different 2D materials show different properties and applications. In this paper, the characteristics and performance of rich layered 2D materials under different types of doped elements are comprehensively reviewed. Firstly, 2D materials are classified according to their crystal structures. Secondly, conventional experimental methods of charge doping and heterogeneous atom substitution doping are summarized. Finally, on the basis of various theoretical research results, the properties of several typical 2D material representatives under charge doping and different kinds of atom substitution doping as well as the inspiration and expansion of doping systems for the development of related fields are discussed. Through this review, researchers can fully understand and grasp the regulation rules of different doping engineering on the properties of layered 2D materials with different crystal structures. It provides theoretical guidance for further improving and optimizing the physical properties of 2D materials, improving and enriching the relevant experimental research and device application development.

Graphite Cast Iron GGG40 for Disposal Containers: The Corrosion Mechanism in Opalinus Clay Water

The overpack of the Pollux® 10 container, taken as a reference for the storage of fuel elements in different types of host rocks, is manufactured from spheroidal graphite carbon steel (GGG 40 / 0.7040) [1]. The near field environment after emplacement is constituted by bentonite, which turns moisty, warm, and anaerobic after some decades because of the decay of the heat generation and the consumption of oxygen by reaction with the container wall, microbes, and minerals [2]. Thus, the corrosion mechanism of metal containers in these conditions is an essential issue for the design of repository concepts of radioactive waste.For a better understanding of the corrosion processes taking place at the interface of steel and saturated bentonite, electrochemical and surface chemical analysis, including SEM-EDX and local XPS were performed on steel in Opalinus Clay water under different temperatures, pH´s and pressures. Electrochemical measurements were carried out in a dedicated reactor cell for working at high temperature and high pressures (up to 150 bars). A Solartron electrochemical interface 1287 connected to a frequency analyzer 1260 was used.Polarization curves performed in deaerated solutions are characterized by a low cathodic constant current separating the onset of water reduction and the active dissolution. The presence of oxygen increases the current of the cathodic plateau shifting the corrosion potential towards more positive values. The metallographic structure of the steel give rise to local predominantly anodic and cathodic elements, i.e., ferritic, and pearlitic phases, on the one side and cementite and graphite on the other side, respectively.The dissolution of the active phases is controlled by the formation of an oxide film mainly constituted by magnetite and silicates containing Fe, Al, Mg and Cr formed by oxidation of the silicon contained in the alloy. SEM pictures obtained after 48 h of corrosion under anaerobic conditions and 5 bar of pressure show the deposition of silicates with different morphologies: as clusters of spheres and as hexagonal platellets (see fig.1). Under 100 bar of pressure, however, an rather etched aspect can be observed, revealing clearly the different metallographic phases.The impedance diagrams obtained at the corrosion potential shows an inductive loop at low frequency. Based on the shape of potentiostatic anodic current transients, the inductive loops can be ascribed to the dynamic of formation-dissolution of the interfacial oxide-silicate film. The effect of hydrostatic pressure is particularly interesting. The shiny optical aspect of the surface after corrosion under pressure can a priori be explained by the reducing atmosphere created by water reduction under these conditions.The significance of the formation of silicates is evident in the surface analysis of samples after long-term experiments in contact with Wyoming bentonite saturated with pore Opalinus Clay water. TEM pictures of a cross sectional lamella including part of graphite sphere shows the formation of a silicate film covering the corroding surface with an irregular adherence. The accumulation of silicates at the surface creates an additional barrier for the metal dissolution, which reduces the corrosion rate by a factor of thousand.

Сортировка коллизий пересечения

The article describes the features of the transition to information modeling at the design stage, which lead to an increase in the number of digital information models. Quantitative and qualitative improvement of models entails an increase in the time spent by highly qualified labor resources. A method is proposed for sorting intersection collisions for their subsequent correction in order to rationalize the use of labor resources in design organizations, and the organization of work to improve the quality of digital information models, and design solutions in general. Thus, using the collision sorting method, assigning weights to elements, it is possible to increase the productivity of qualified engineers through the rational use of labor resources.
 The greatest number of collisions consist of the intersection of walls with walls, from this it can be concluded that the tool with which the walls are modeled is used incorrectly, there is probably a duplication of elements. The value of weak intersections in the future can be reduced, thereby the verification conditions will become tougher, there will be more intersection collisions, the quality of the CIM will increase after their correction. The values of the weights in this study are assigned based on the fact that the load-bearing elements have a higher priority.
 As further research, it is possible to determine the weights for most of the CIM elements in different types of capital construction projects by expert evaluation and make methodological recommendations.

Corrosion processes at the GGG40 steel–bentonite interface

Abstract. Spheroidal graphite cast iron (GGG40/0.7040) is used as an overpack material for the reference Pollux 10 container, a prototype for the storage of fuel elements in different types of host rocks (Hassel et al., 2019). Corrosion processes are expected to be triggered after some decades, as the contacting bentonite, which is used as fill material, becomes soggy because of the decay of the fission heat generation and the intrusion of pore water as the temperature decreases under the condensation point (King and Padovani, 2011). The distinct electrochemical reactivities of the graphite, ferrite, pearlite, and cementite phases exposed by this material introduce local galvanic elements which influence the topographic evolution of degradation (Spence, 2005). The aim of this work is to elucidate the corrosion dynamics of active and passive areas by following the chemical evolution at the interface of cast iron–bentonite during the first stages after its saturation with geological pore water. Polarization experiments and electrochemical impedance spectroscopy were applied to monitor the corrosion process in a bentonite cell, where GGG40 steel is put into contact with a light compacted Wyoming bentonite slurry 1 : 10 w/w of bentonite to Opalinus Clay pore water (Fig. 1a). Experiments were performed at 30 and 50 ∘C for longer than 3 months. The surface chemistry and morphological changes were investigated by local XPS, SEM-EDX, and TEM (X-ray photoelectron spectroscopy, scanning electron microscopy with energy dispersive X-ray, and transmission electron microscopy, respectively). These experiments were complemented with corrosion studies performed in pore water under different temperatures, hydrostatic pressures, and pH and with and without dissolved oxygen. The polarization curves indicate a constant corrosion rate of GGG40 steel in saturated bentonite after 30 d. SEM micrographs reveal a preferential dissolution of the ferrite phase around the graphite spheres and the ferrite lamellae contained in the pearlitic eutectic. A strong localized dissolution of ferrite along the graphite boundary can be also observed; this is a typical case of crevice corrosion caused by the unhindered access of oxygen to the graphitic cathodic areas (Wang et al., 2022). The surface chemical studies indicate the accumulation of iron oxides, which can be attributed to a hydrated magnetite and the formation of iron silicates (Zhang et al., 2021). TEM pictures of a cross-sectional lamella, including part of graphite sphere, show the formation of a silicate film covering the corroding surface with an irregular adherence (Fig. 1b). The initial relatively high corrosion rate of GGG40 steel can be attributed to the dissolution of the more active ferrite with the formation of poorly passivating iron oxides and silicates. The system is driven towards the dissolution of pearlite at more positive electrode potentials. The bentonite slurry limits the access of oxygen to the graphitic cathodic areas, reducing the corrosion rate by 1 order of magnitude in comparison with that in aerated pore water. A surface enrichment of cementite with superior passive properties and the neutralization of the local elements by approaching the corrosion potential of graphite (Kadowaki et al., 2019) is also expected. Thus, the consumption of oxygen and the transport limitation of the cathodic reaction by bentonite forecast a considerable reduction in the degradation of the container after a sacrificial corrosion phase.

Characteristics of Seismogenic Dust Particles from a Mountain and Their Significance for Paleoseismic Records in a Tufa Section: A Case Study of Jiuzhaigou, China

The sedimentary characteristics of the special interlayer contained in the section of the Sparkling Lake dam revealed by the 8 August Jiuzhaigou earthquake in 2017 are obviously different from the tufa in the dam body, and they are considered to be historic flood relics. Based on the study of the particulate matter from the 8 August Jiuzhaigou earthquake, this study combined comparative petrographic, mineralogical, geochemical, and chronological studies of the special interbedded sediments of the Sparkling Lake dam with other genetic samples to obtain homology information and genetic links and to explore the tufa depositional dynamics and earthquake disaster subsidence. The paleoseismic benefit in the discontinuity layer was explored, and the paleoseismic information embedded in the profiles was extracted, providing a new idea for reconstructing the paleoseismic events in the tufa deposition sequence. According to X-ray diffraction, laser particle size analysis, and scanning electron microscope experiments, the particulate matter in the Jiuzhaigou mountains has its own specific mineralogical characteristics. The mineral composition of the particulate matter is basically calcite. The particle size is large, and single particles are mostly angular and subangular. The fracture morphology observed under the single-particle microscope was uneven, showing the characteristics of the dust caused by earthquake disasters. The geochemical analysis data show that the distribution patterns of rare earth elements in different types of particulate matter in the same area have similar characteristics. Moreover, an analysis of the elements Rb, Sr, and Ba shows that the particulate matter in Jiuzhaigou has a strong correlation (R2 = 0.9941), indicating the stability and uniformity of the material source. The source of the particulate matter was limestone of the carbonate strata from the Devonian to the Triassic. Combined with mineralogy and grain size morphology, the interbedded particles in the tufa depositional profile have the potential application of paleoseismic archives to record extreme seismic events. According to the chronological data of the special interlayer sediments in the tufa dam body, the paleoseismic age is inferred to be 1220 ± 30 BP. Therefore, the tufa bedding can be related to the paleoearthquake, and the special interlayer of the tufa section can be used to reconstruct paleoearthquakes.

Transition process from fossil energy to photovoltaic energy power of ethnic communities belonging to the natural parks in the Colombian Pacific: A diagnostic study

AbstractFor an energy transformation project with emerging technologies to be viable and sustainable, it requires community participation, the social appropriation of the knowledge of the technology to be implemented, and the assessment of its social and environmental impact. In this context, this research carried out a diagnostic study on the energy consumption of ethnic communities belonging to National Natural Parks in the Colombian Pacific in order to provide indicators of the potential and relevance of portable photovoltaic solar energy for small-scale energy supply in these communities. For this purpose, four strategic sites in the district of Buenaventura were selected to implement questionnaires to collect technical data on demographic characterization (age, occupation, ethnicity, educational level, residence time), solar exposure, architectural infrastructure, energy sources, use of electrical elements, and energy consumption. The study focused on five sectors of interest: (i) housing, (ii) microenterprises, (iii) schools, (iv) health centers, and (v) boats. Fuelwood and diesel were found to be the main sources of energy in the region; this represents continuous pollution of gases and noise. Electricity is supplied mainly through diesel power generators with a cost per kWh higher by 86% than the average value in the interconnected area. It was identified that the most representative economic activities of these communities are fishing, and other activities associated with tourism; therefore, after diagnosing the use of low-power electrical elements in different types of boats, we propose a portable photovoltaic solar system adjusted to local environmental conditions and the needs of artisanal fishing.

Calibrating of a Simulation Model to Predict the Flexural Capacity of Pre-Stressed Concrete Beams

Simulation models based on finite elements are currently indispensable tools for predicting the structural behavior of both reinforced and pre-stressed concrete elements. This work develops a simulation model of structural linear elements of pre-stressed concrete, using the finite element method (FEM). The main aim was to calibrate the model to predict the flexural capacity of structural elements, and so be able to undertake a double optimization through the design and the resistant behavior of the elements. Different flexural experiments were conducted in laboratory conditions on real concrete elements of different types (pre-stressed joist and tubular pre-stressed joist). In parallel, the same structural elements were analyzed by MEF simulation to calibrate the model to the real experiments. FEM analysis was performed using the ATENA software developed by Červenka Consulting (Czech Republic), especially recommended for the analysis of structural concrete elements using non-linear methods. The model was calibrated using the results obtained in real load test experiments obtained in a loading frame of 500 kN capacity. The calibration analysis shows a good fit of the results to the actual test experiments, obtaining average errors of 6% in the analysis–experiment comparison. The results of the simulation suggest that to obtain the optimum strength levels for the different typologies analyzed, it is essential to control the pre-stressing losses in the manufacturing process of the joist. The flexural capacity of all elements can be increased by around 20–30% when the real pre-stressing losses are fitted to the theoretical ones estimated.

Use of longitudinal wave in non-destructive methods: approach to foundation and retaining elements

Non-destructive tests (NDT) are used to verify the length or integrity of elements embedded in soils or rocks. These elements can be piles in foundations or nails and tiebacks in retaining walls. NDTs differ by the types of waves, ways to generate and receive the signal and to analyze data. Tests using sonic wave do not require a pre-installed pipe or wire and they are based on acoustic impedance theory. Despite its dissemination on piles, the application in retaining elements is recent and requires more studies to increase knowledge about these methods. This paper aims to present studies of sonic wave methods in foundation and retaining elements, presenting results, similarities, and differences. Studies from different dates are presented with their relevance, considerations for the different types of elements tested, objectives and methodologies used, to evidence the variables involved within this solution. The sonic test in foundation is widespread and has a greater number of studies. Withing this paper, the variables that interfere in the results of these methods were observed: the velocity of propagation of the sonic wave, the soil stiffness, the location of wave generation and reception and the type of hammer used, evidencing the necessity of further studies, especially in retaining elements.