Now showing items 1-10 of 10

Effects of biodeterioration on the mechanical properties of concrete

Marquez-Peñaranda, J. F.; Sanchez-Silva, M.; Husserl, J.; Bastidas-Arteaga, E. (Materials And StructuresPaíses Bajos, 2015-12-29)

Concrete biodeterioration in sewers and structures subjected to environments rich in hydrogen sulfide has been related to the activity of sulfur oxidizing bacteria (SOB). In previous studies, the effect of the activity of ...
Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)

Yung Vargas, Yee Wan; Cordoba Maquilon, Jorge Eliecer; Rondón-Quintana, Hugo Alexander (TecnuraColombia, 2017-02-01)

Contexto: Las mezclas asfálticas drenantes son definidas como aquellas cuyos vacíos con aire oscilan entre 20% y 25%, y emplean como ligante, un asfalto modificado con algún polímero principalmente elastomérico. A diferencia ...
A proposal for updating the response spectrum of San Jose de Cucuta, Colombia

FLOREZ-GONGORA, CARLOS; MARQUEZ-PEÑARANDA, JORGE FERNANDO; Lozano Lozano, Carlos Fernando (IOP Conference Series: Materials Science and EngineeringColombia, 2020-06-29)

An analysis of seismic signals captured in three stations of the network of accelerographs of the Colombian Geological Service (SGC, by its acronym in Spanish) was developed for the city of San Jose de Cucuta, Colombia. ...
Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate

FLOREZ-GONGORA, CARLOS; Garzón-Peña, A T; Molina-Giraldo, R D (Journal of Physics: Conference SeriesReino Unido, 2020-08-05)

High-plasticity clays can be stabilized by the addition of a small percentage of sodium silicate. Sixteen mixtures of 4000 g with different concentrations of sodium silicate at difference percentage were designed, to which ...
Proposal for a system model for offline seismic event detection in Colombia

Miranda, Julian; Flórez Abril, Angélica; Ospina, Gustavo; Gamboa, Ciro Alberto; Altuve, Miguel; FLOREZ-GONGORA, CARLOS (Future InternetSuiza, 2020-12-18)

This paper presents an integrated model for seismic events detection in Colombia using machine learning techniques. Machine learning is used to identify P-wave windows in historic records and hence detect seismic events. ...
The use of mobile phones for the prevention and control of arboviral diseases: a scoping review

Carrillo, Maria Angelica; Kroeger, Axel; Cardenas, Rocio; Diaz Monsalve, Sonia; Runge-Ranzinger, Silvia (BMC Public HealthReino Unido, 2021-01-09)

Background: The rapid expansion of dengue, Zika and chikungunya with large scale outbreaks are an increasing public health concern in many countries. Additionally, the recent coronavirus pandemic urged the need to ...
The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Chackalackal, Dhia Joseph; Rivera Ramirez, Tatiana; Carrillo, Maria Angelica; Asa’Ad Al-Aghbari, Ahmed; Jang, Su Yeon; Vincent, Jose; Joshi, Anand; Banjara, Megha Raj; Asaga, Peter; Cardenas Sanchez, Rocio; Villa, Juan Manuel; Diaz Monsalve, Sonia; Kroeger, Axel (Pathogens and Global HealthReino Unido, 2021-03-04)

During the Covid-19 pandemic, rich countries employed lockdown and physical distancing policies for transmission control. However, the question still remains whether these measures are also suitable in countries with a ...
The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Chackalackal, Dhia Joseph; Ad Al-Aghbari, Ahmed Asa; Yeon Jang, Su; Rivera Ramirez, Tatiana; Anand Joshi, Jose Vincentc; Banjara, Megha Raj; Peter Asaga; Cardenas Sanchez, Rocio; Carrillo, Maria Angelica; Villa, Juan Manuel; Diaz Monsalve, Sonia; Kroeger, Axel (Pathogens and Global Health, 2021-03-04)

During the Covid-19 pandemic, rich countries employed lockdown and physical distancing policies for transmission control. However, the question still remains whether these measures are also suitable in countries with a ...
Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes

AMBOA SUAREZ, AUDIN ALOISO; Hernández Álvarez, Cesar Augusto; Ramirez Leal, Pastor (Revista de Ciencias SocialesColombia, 2021-08)

La gestión pública eficiente busca generar actuaciones transparentes que logren satisfacer necesidades básicas de los habitantes. El objetivo del artículo es identificar las percepciones de habitantes de la ciudad ...
Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis

Su Yeon, Jang; Hussain-Alkhateeb, Laith; Rivera Ramírez, Tatiana; Ahmed Asa'ad, Al-Aghbari; Chackalackal, Dhia Joseph; Cárdenas Sánchez, Rocío; Carrillo Diaz, María Angélica; Oh, En Hwan; Alfonso Sierra, Eduardo Andrés; Pía, Oechsner; Kibiwott Kirui, Brian; anto, martin; Díaz Monsalve, Sonia; Kröger, Axel (BMC Infectious Diseases, 2021-10-02)

Lockdown measures are the backbone of containment measures for the COVID-19 pandemic both in high-income countries (HICs) and low- and middle-income countries (LMICs). However, in view of the inevitablyoccurring second ...

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Effects of biodeterioration on the mechanical properties of concrete
...
Marquez-Peñaranda, J. F. | 2015-12-29

Concrete biodeterioration in sewers and structures subjected to environments rich in hydrogen sulfide has been related to the activity of sulfur oxidizing bacteria (SOB). In previous studies, the effect of the activity of SOB on concrete structures has been linked mainly to weight loss. In our work we have investigated, in addition to the weight loss, the variations in porosity and compressive strength. The main objective of this paper is to explore, under controlled conditions, the effect of biodegradation of non-submerged samples, on both the physical properties and the mechanical performance. Towards this aim, cement mortar samples inoculated with pure cultures of Acidithiobacillus thiooxidans, Halothiobacillus neapolitanus, and a consortium containing both strains, were exposed to an H2S-rich environment. Changes in physical properties, including weight and porosity, and compressive strength were measured over 300 days. The results showed that the greatest reduction of weight and compressive strength was observed in samples inoculated with the consortium (7 and 52 %, respectively); while the largest variation in porosity was observed in samples inoculated with A. thiooxidans (27 %). These results were used to obtain relationships between the amount of sulfur available over time with specific physical and mechanical properties; i.e., compressive strength, porosity, weight loss, and physical appearance.

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Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)
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Yung Vargas, Yee Wan | 2017-02-01

Contexto: Las mezclas asfálticas drenantes son definidas como aquellas cuyos vacíos con aire oscilan entre 20% y 25%, y emplean como ligante, un asfalto modificado con algún polímero principalmente elastomérico. A diferencia de otros estudios reportados sobre el tema, se evaluó el efecto de la temperatura de mezcla entre el asfalto modificado con GCR y el material pétreo (160 ºC y 170 ºC), y la variación de las temperaturas de compactación para cada una de ellas (110 ºC, 130 ºC, 150 ºC) y (150 ºC, 160 ºC 170 ºC) respectivamente. Método: El presente estudio evaluó en laboratorio, la resistencia al desgaste por abrasión (ensayo Cántabro) y la rigidez bajo carga monotónica (ensayo Marshall) y cíclica (módulo resiliente) que experimentó una mezcla asfáltica drenante MD fabricada con asfalto modificado con grano de caucho reciclado de llanta (GCR) por vía húmeda (se modifica el asfalto con el GCR a alta temperatura). Como asfalto base para la fabricación de las mezclas se utilizó cemento asfáltico CA 60-70 (PG 64-22). Resultados: se reporta un incremento notable en la resistencia al desgaste por abrasión, a la resistencia bajo carga monotónica y la rigidez bajo carga cíclica de la MD cuando se modifica con GCR. Conclusiones: Como conclusión general se resalta la influencia que tienen las temperaturas de mezcla entre el asfalto y el GCR, así como la de compactación (asfalto modificado y agregado) sobre el comportamiento de la MD modificada con GCR.

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A proposal for updating the response spectrum of San Jose de Cucuta, Colombia
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FLOREZ-GONGORA, CARLOS | 2020-06-29

An analysis of seismic signals captured in three stations of the network of accelerographs of the Colombian Geological Service (SGC, by its acronym in Spanish) was developed for the city of San Jose de Cucuta, Colombia. Earthquake Equivalent, Response Analysis (EERA) and DEGTRA4 software were used for analysis, processing and calculation of signal response spectra during the characterization and propagation modelling of the signal by profiles. For the accelerograms family, a normalization factor computed with respect to the Peak Ground Acceleration (PGA) was obtained by superposition against the typical design spectrum of the Colombian earthquake resistant code (NSR10). It was found that there is a band of frequencies above the maximum acceleration zone of the design spectrum of the current standard. This suggests a revision of the seismic threat of the city of Cucuta and the urgent need to develop the seismic microzoning, which would allow a substantial reduction of the seismic risk.

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Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate
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FLOREZ-GONGORA, CARLOS | 2020-08-05

High-plasticity clays can be stabilized by the addition of a small percentage of sodium silicate. Sixteen mixtures of 4000 g with different concentrations of sodium silicate at difference percentage were designed, to which were carried out physical, mechanical and chemical characterization tests that allowed to analyze the behavior at intervals of time. Physical, mechanical and chemical properties of the soil were evaluated. Using stabilization with sodium silicate in high plasticity clays, changes in the physical, mechanical, and chemical parameters of the soil were achieved. Having satisfactory results with 3% saturation, optimal concentration, at time intervals of 2 days and 1 month; Then as time passes the soil tries to return to its initial properties, which establishes that the concentration of the Silicate and its effect on the physical and mechanical properties of the soil should be checked over a longer time interval. Studying the physical, mechanical, and chemical parameters of high plasticity clays by adding multiples mixtures of sodium silicate contributes to the understanding of the soil behavior on the pressure condition.

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Proposal for a system model for offline seismic event detection in Colombia
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Miranda, Julian | 2020-12-18

This paper presents an integrated model for seismic events detection in Colombia using machine learning techniques. Machine learning is used to identify P-wave windows in historic records and hence detect seismic events. The proposed model has five modules that group the basic detection system procedures: the seeking, gathering, and storage seismic data module, the reading of seismic records module, the analysis of seismological stations module, the sample selection module, and the classification process module. An explanation of each module is given in conjunction with practical recommendations for its implementation. The resulting model allows understanding the integration of the phases required for the design and development of an offline seismic event detection system.

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The use of mobile phones for the prevention and control of arboviral diseases: a scoping review
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Carrillo, Maria Angelica | 2021-01-09

Background: The rapid expansion of dengue, Zika and chikungunya with large scale outbreaks are an increasing public health concern in many countries. Additionally, the recent coronavirus pandemic urged the need to get connected for fast information transfer and exchange. As response, health programmes have -among other interventions- incorporated digital tools such as mobile phones for supporting the control and prevention of infectious diseases. However, little is known about the benefits of mobile phone technology in terms of input, process and outcome dimensions. The purpose of this scoping review is to analyse the evidence of the use of mobile phones as an intervention tool regarding the performance, acceptance, usability, feasibility, cost and effectiveness in dengue, Zika and chikungunya control programmes. Methods: We conducted a scoping review of studies and reports by systematically searching: i) electronic databases (PubMed, PLOS ONE, PLOS Neglected Tropical Disease, LILACS, WHOLIS, ScienceDirect and Google scholar), ii) grey literature, using Google web and iii) documents in the list of references of the selected papers. Selected studies were categorized using a pre-determined data extraction form. Finally, a narrative summary of the evidence related to general characteristics of available mobile health tools and outcomes was produced. Results: The systematic literature search identified 1289 records, 32 of which met the inclusion criteria and 4 records from the reference lists. A total of 36 studies were included coming from twenty different countries. Five mobile phone services were identified in this review: mobile applications (n = 18), short message services (n=7), camera phone (n = 6), mobile phone tracking data (n = 4), and simple mobile communication (n = 1). Mobile phones were used for surveillance, prevention, diagnosis, and communication demonstrating good performance, acceptance and usability by users, as well as feasibility of mobile phone under real life conditions and effectiveness in terms of contributing to a reduction of vectors/ disease and improving users-oriented behaviour changes. It can be concluded that there are benefits for using mobile phones in the fight against arboviral diseases as well as other epidemic diseases. Further studies particularly on acceptance, cost and effectiveness at scale are recommended.

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The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries
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Chackalackal, Dhia Joseph | 2021-03-04

During the Covid-19 pandemic, rich countries employed lockdown and physical distancing policies for transmission control. However, the question still remains whether these measures are also suitable in countries with a fragile economy, which rests mainly on the informal sector. The impacts of lockdown measures in disadvantaged population strata in six low- and middle-income countries (LMICs) were reviewed using i) 93 media reports and ii) 17 published scientific papers. This review showed that those who suffered the most from the lockdown were migrants, workers in the large informal sector, small businesses, slum dwellers, women and elderly, revealing the social, cultural and economic inequalities of societies. Financial and food support for the poor was inadequate and sometimes mismanaged. In the better organized societies, the resilience was stronger (South Korea, Kerala/India) but here also the poor had to suffer the most. It is strongly recommended that outbreak response strategies should particularly focus on the poor and vulnerable population.

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The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries
...
Chackalackal, Dhia Joseph | 2021-03-04

During the Covid-19 pandemic, rich countries employed lockdown and physical distancing policies for transmission control. However, the question still remains whether these measures are also suitable in countries with a fragile economy, which rests mainly on the informal sector. The impacts of lockdown measures in disadvantaged population strata in six low- and middleincome countries (LMICs) were reviewed using i) 93 media reports and ii) 17 published scientific papers. This review showed that those who suffered the most from the lockdown were migrants, workers in the large informal sector, small businesses, slum dwellers, women and elderly, revealing the social, cultural and economic inequalities of societies. Financial and food support for the poor was inadequate and sometimes mismanaged. In the better organized societies, the resilience was stronger (South Korea, Kerala/India) but here also the poor had to suffer the most. It is strongly recommended that outbreak response strategies should particularly focus on the poor and vulnerable population.

LEER
Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes
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AMBOA SUAREZ, AUDIN ALOISO | 2021-08

La gestión pública eficiente busca generar actuaciones transparentes que logren satisfacer necesidades básicas de los habitantes. El objetivo del artículo es identificar las percepciones de habitantes de la ciudad fronteriza de Cúcuta, en Colombia, sobre la gestión de sus gobernantes en aspectos relacionados con educación, empleo, salud, seguridad y vivienda. El componente metodológico estuvo determinado por el paradigma cuantitativo, con diseño descriptivo, no experimental, de corte transversal. Se aplicó un cuestionario de 16 ítems a 2.284 participantes de las diez comunas de la ciudad. Los resultados muestran que 63,5% de los encuestados manifestó que la ciudad ha empeorado en el último año, en contraste con 27,5% que considera que ha mejorado tras la aplicación de las políticas de gobierno, mientras que 9% no respondió. Se concluye, que la insatisfacción de la mayoría de los habitantes con la gestión del gobierno municipal se relaciona, principalmente, con el alto porcentaje del trabajo informal, la falta de oportunidades para empleo formal y los deficientes sistemas de salud y educación. Problemas que no surgieron con la pandemia, sino que se han configurado desde años anteriores, ante la poca ayuda que ha brindado el gobierno municipal para mitigar los problemas sociales de la región.

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Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis
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Su Yeon, Jang | 2021-10-02

Lockdown measures are the backbone of containment measures for the COVID-19 pandemic both in high-income countries (HICs) and low- and middle-income countries (LMICs). However, in view of the inevitablyoccurring second and third global covid-19 wave, assessing the success and impact of containment measures on the epidemic curve of COVID-19 and people’s compliance with such measures is crucial for more effective policies. To determine the containment measures influencing the COVID-19 epidemic curve in nine targeted countries across high-, middle-, and low-income nations.

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Repositorio Digital

Browsing Geotecnia Ambiental – GIGA by Issue Date

Effects of biodeterioration on the mechanical properties of concrete

Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)

A proposal for updating the response spectrum of San Jose de Cucuta, Colombia

Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate

Proposal for a system model for offline seismic event detection in Colombia

The use of mobile phones for the prevention and control of arboviral diseases: a scoping review

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes

Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis

Envíos recientes

Effects of biodeterioration on the mechanical properties of concrete

Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)

A proposal for updating the response spectrum of San Jose de Cucuta, Colombia

Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate

Proposal for a system model for offline seismic event detection in Colombia

The use of mobile phones for the prevention and control of arboviral diseases: a scoping review

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes

Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis

Portales Institucionales

Enlaces de Interés

Contactos

Browsing Geotecnia Ambiental – GIGA by Issue Date

Effects of biodeterioration on the mechanical properties of concrete ﻿

Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR) ﻿

A proposal for updating the response spectrum of San Jose de Cucuta, Colombia ﻿

Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate ﻿

Proposal for a system model for offline seismic event detection in Colombia ﻿

The use of mobile phones for the prevention and control of arboviral diseases: a scoping review ﻿

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries ﻿

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries ﻿

Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes ﻿

Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis ﻿

Envíos recientes

Effects of biodeterioration on the mechanical properties of concrete

Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)

A proposal for updating the response spectrum of San Jose de Cucuta, Colombia

Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate

Proposal for a system model for offline seismic event detection in Colombia

The use of mobile phones for the prevention and control of arboviral diseases: a scoping review

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes

Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis

Portales Institucionales

Effects of biodeterioration on the mechanical properties of concrete

Evaluación del desgaste por abrasión de una mezcla drenante modificada con residuo de llanta triturada (GCR)

A proposal for updating the response spectrum of San Jose de Cucuta, Colombia

Testing stabilization of high-plasticity clays used in sloping terrain by adding sodium silicate

Proposal for a system model for offline seismic event detection in Colombia

The use of mobile phones for the prevention and control of arboviral diseases: a scoping review

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

The Covid-19 pandemic in low- and middle-income countries, who carries the burden? Review of mass media and publications from six countries

Gestión pública en una ciudad fronteriza colombiana: La mirada de sus habitantes

Factors shaping the COVID‑19 epidemic curve: a multi‑country analysis