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The wastewater treatment at paper industry that uses recycled fibers as one of its raw materials generates a sludge rich in cellulose fibers, which once dehydrated is called "paper waste". This waste has become an environmental problem because of its high generation rate. Although several alternatives of valorization have been studied, in Medellin none of them has been implemented on an industrial scale; the necessity is still there, that is why the land disposal of this waste appears as the most immediate way to manage it. Combined with the problem of disposition, it is the selection of the suitable site to make it, for which a methodology to be applied in the evaluation and selection of the optative sites for the disposition of remainders of paper industry was developed. [ABSTRACT FROM AUTHOR]

A compilation of structural fire statistics at the national and international levels is presented in the paper. At the national level, data were obtained from Medellín, Manizales and Pereira Cities, the National Unit for Disaster Risk Management (UNGRD), which collects relevant information reported by the National Fire Department of Colombia (DNBC) and from the DNBC. These statistics allow to identify the types of buildings in which structural fires are most frequent and the number of people injured or deceased in structural fires in Colombia. At the international level, it was possible to identify the number of structural fires reported by different countries from 1996 to 2018. These data were reported by the International Association of Fire and Rescue Services (CTIF). It was possible to establish from this information that Colombia presents values lower than 0.3 fires per thousand of inhabitants, surpassed by European countries and the United States, where this index is higher than 1. It should be clarified that the methodology for the elaboration of fire statistics includes international parameters related to the comparison of damages caused by structural fires with the population, which do not apply in Colombia in all cases. Thus, the results were analyzed with great caution, taking into account that, when comparing the results with the population of Colombia, data were presented that do not represent the current state of the country in the face of fire events. This was due to the quality of the information available in Colombia. The paper includes recommendations to be included in the next version of the Colombian Code for Earthquake-Resistant Construction (NSR). [ABSTRACT FROM AUTHOR]

Strawberry is a product that, due to its nutritional characteristics, has become an accessible foodstuff for consumption; however, it is delicate and perishable. This condition complicates its transit through the supply chain, destabilizes its price in the market and makes the benefit for producers uncertain. Thus, this study shows opportunities for creating value and sustainability for small strawberry producers, considering the economic context, the supply chain, the agri-food production chain and the value chain. Thus, this study makes it possible to show the lack of awareness of agricultural producers about the entire system in which they are involved, the low articulation between actors and the limited execution of collective actions that lead to a greater benefit for producers, within a paradigm of value creation and sustainable development. Strawberry is a product that, due to its nutritional characteristics, has become an accessible foodstuff for consumption; however, it is delicate and perishable. This condition complicates its transit through the supply chain, destabilizes its price on the market and makes the benefit uncertain for producers. This research was aimed at identifying opportunities for value creation and sustainability for small strawberry growers. The study began with a literature review on the strawberry supply chain (114 papers) in scientific databases, then data from public databases were reviewed, then additional literature on the production-agri-food and value chains was explored, a field visit was made, a community workshop was held, including discussions and exchange of information with strawberry producers in a municipality in Colombia, which is known for being one of the main strawberry producers in this country of agricultural vocation. Based on the information collected, an overview (economic context) of strawberry produce in Colombia was elaborated and the production and marketing of strawberries in the municipality was characterized from three perspectives: the supply chain, the agro-food production chain and the value chain. Thus, this study reveals the lack of knowledge of agricultural producers about the entire system in which they are involved, the low articulation between actors and the limited implementation of collective actions that lead to greater benefits for producers, within a paradigm of value creation and sustainable development. [ABSTRACT FROM AUTHOR]

This paper presents the determination of antioxidant capacity and total polyphenol content in both aqueous and organic extracts of Stevia Rebaudiana stems variety Morita II. The antioxidant capacity was determined through various in vitro assays: Method 2 1,1-diphenylpicryl- hidrazyl (DPPH) assay, discoloration 2,2'-azino-bis-3-ethylbenzthiazoline-6- sulfonic acid (ABTS) assay, ferric ion reducing antioxidant power (FRAP), and total polyphenols by Folin-Ciocalteu. The results were analyzed by Person's correlation. This work was done in order to give added value to the stem of Stevia and their potential use as a source of antioxidant compounds. The results indicate that extracts of Stevia stems grown in Colombia have greater inhibitory activity of free radicals compared to reports in the literature regarding leaf and stem. Therefore it can be concluded that the stems are an accessible source of antioxidants. [ABSTRACT FROM AUTHOR]

This paper analyzes the technical and economical feasibility of generating electricity from low temperature geothermal resources available in oil oilfields in Colombia using Organic Rankine Cycle technology. The water obtained as a byproduct during oil extraction has a temperature of 118°C at wellhead and 80°C on average in disposal stages; the water flow rates reach values of 2.38 m³/s. In order to improve the efficiency of the conventional ORC cycle, additional heating and cooling alternatives were evaluated for the hot and cold streams, respectively. Our results show that 1,165.1 MWh of annual energy would be produced in one of the fields by a comercial 280 kW-ORC. The correlated generation cost would be around 0,102 U$/KWh. According to this study, the implementation of ORC tools are not feasible because higher temperatures are required. [ABSTRACT FROM AUTHOR]

This paper propose an additional plan of production in a Company, including employees in a handicap condition, which will count with different times to execute the different tasks and sometimes incompatible in specific activities. The Model of mixed integer linear programming seeks to maximize production as well as the respective cash flow. The tributary benefits of the Colombian government associated to the inclusion of handicap condition personnel, are considered for the model. The Model is validated with a case study. [ABSTRACT FROM AUTHOR]

To solve the problem of secondary distribution systems planning, this paper proposes a methodology using a tabu search algorithm as a solution technique. The problem is formulated as a nonlinear mixed-integer model, which takes into account the location and capacity of new elements (distribution transformers and primary-secondary distribution networks), relocation of existing distribution transformers, increasing the capacity of existing elements, secondary network reconfiguration, and phase balance. It also considers the costs associated with connections between primary and secondary networks and energy losses in distribution transformers. The methodology is applied to two test cases: in the first, a comparative analysis with the Chu-Beasley genetic algorithm is made to verify the efficiency of the proposed methodology; and in the second, the results are analyzed in a Colombian distribution system. In both cases, the results are of high quality, supporting the proposed methodology. [ABSTRACT FROM AUTHOR]

In this paper, we present a method based on liquid chromatography column to quantify the chemical composition of asphalt cements manufactured in Colombia, under the environment by determining the SARA fractions. The method was applied to thin layers of asphalt 60/70 and 80/100 to determine changes in the chemical composition of the material after exposure for 12 months in the weather conditions in the city of Bogotá; SARA tests were performed to the original asphalt, 1, 3, 6, 9 and 12 months aged respectively. SARA trials showed that aging caused a decrease in the fraction of aromatics and asphaltenes increased compared to non-aged asphalt. The reduction of aromatics and resins could be responsible for the hardening observed in the asphalt, which had a stiff and brittle consistency; that leads to obtaining higher colloidal index. The performed method established possible correlations between the chemical composition of asphalt and its mechanical properties. [ABSTRACT FROM AUTHOR]

The use of real accelerograms as input in dynamic analysis is desirable as they provide realistic information about the nature of the strong ground motion; in addition, accelerograms capture different characteristics that can be produced by earthquakes at different locations. Colombian design code allows for the use of real accelerograms as input to time-history analysis. The horizontal component of a minimum of three different accelerograms is required by the code; all of the accelerograms must be representative of the expected ground motion at the site. In this paper the database of Colombian National Network of Accelerographs (Red Nacional de Acelerógrafos de Colombia, RNAC) is analyzed in order to assess the availability of records for different ground motion characteristics for their use as input in dynamic analysis. Groups of accelerograms that could be used as input for dynamic analysis were identified. However, if only records from the RNAC are used, it is not possible to completely cover the selection requirements specified on the Colombian design code. [ABSTRACT FROM AUTHOR]

This paper aims to provide the theoretical and practical elements of the use of interest rate swaps (IRS) and cross currency swaps (CCS) by Colombian companies, as hedging tools to manage their interest and exchange rates exposures. It will proffer a deep analysis of the advantages and challenges of the use of swaps in the Colombian economic environment and provide tailored solutions to obstacles faced in areas such as the understanding of the characteristics and the associated risks of the product, the valuation under the particularities of the Colombian financial markets, and the accounting and tax treatment and its effects. This article focuses in the design of a pricing model that, applying bootstrapping and cubic splines interpolation techniques, estimates the interest rates structure allowing Colombian real sector companies to obtain indicative IRS and CCS mark to market valuations. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the accepted vision in recent times on the issue of flexibility in manufacturing. Firstly, the topic is introduced, establishing the basis for understanding the importance of corporate strategies and their impact on the competitive advantages of any organization. Then, we explain the flexibility as a strategy of the production system and the internal structure of this concept. Taking these elements well defined, we proceed to identify the types of flexibility and some indicators that explain how to measure in production systems. Finally, through examples, we show the different concepts and some methods of measurement, to contribute in the implementation of the concept of flexibility in the Colombian manufacturing. [ABSTRACT FROM AUTHOR]

In Colombia, the acceptance of resource recovery is demonstrated through the high number of municipalities which have introduced this alternative in their integrated solid waste management plans, together with the increasing number of solid waste management facilities (SWMFs) that have been established. This situation also highlights the need for a comprehensive evaluation of the existing experiences as well as research and development around this topic. In this paper, the performance of five SWMFs located in municipalities in northern Valle del Cauca is analyzed. The analysis shows that, despite the fact that SWMFs have operational deficiencies, features such as markets for their products, employment generation and avoided costs in waste disposal in landfills show sufficient grounds for their continuity. Key elements to strengthen SWMFs performance are long-term awareness of service users, adaptation of technologies to the context, enhancement of managerial capacity and better support to resource recovery within the national political framework. [ABSTRACT FROM AUTHOR]

This paper presents a multicriteria methodology for supplier selection framed in a certification process with the approach of ISO 9001:2000 standard, using fuzzy QFD as a tool for decision making. The model takes into account the needs and expectations of the buyer and considers as a fundamental element of the process the knowledge that the company has about has both about the materials and processes, and candidate suppliers to be selected. This model was applied in a manufacturing company in Colombia. [ABSTRACT FROM AUTHOR]

This paper presents the application of VMI (Vendor Managed Inventory) in a Colombian enterprise that distributes food products. Here it is shown a clear definition of VMI and it is analyzed the key elements and the most important VMI models that can be found in related research literature. Also presents a comparative assessment of two methods proposed in the literature for calculating the replenishment quantities in a VMI context, which are compared with the current procedure implemented for such propose in the company. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the hygiene management based on the compliance with the prerequisites of a HACCP system in 53 agri-food industries operating in the department of Huila in Colombia. The evaluation methodology corresponded to the verification of the compliance of checklists for two instruments: GHYCAL (Management of Hygiene and Quality) and S& Q (Safety and Quality on Food). The results allowed to find levels of hygiene management on a percentage scale and classify 34 companies in low level of compliance, including levels between 0 % and 75 %; 12 companies in basic compliance level, to obtain ratings from 75 % to 95 %, and 7 companies with higher compliance level, with evaluations higher than 95 %; additionally the similarities and differences between companies and between the sectors studied, using multivariate statistical analysis, were assessed. [ABSTRACT FROM AUTHOR]

This paper presents general aspects of the present situation of the use of seismic response-control techniques in Colombian buildings. The most prevalent techniques used worldwide are identified, and the results of a survey conducted among Colombian structural design engineers aimed at detecting some of the reasons why these techniques have not had a significant applicability in the country are presented. The results of the survey reveal that Colombia is still far from being a leading country in the application of seismic response control techniques, and that most entities and practitioners involved in building planning either do not know these techniques or are not well aware of economical benefits as well as improved structural performance. Finally, based on experiences gained in other countries, the use of these techniques in structural design for Colombia buildings is encouraged. [ABSTRACT FROM AUTHOR]

This paper presents a qualitative analysis of the possibility of implementing seismic response control techniques in buildings in Colombia. Given the current local conditions in engineering and construction in the country, herein are presented the main reasons why it is considered that the passive control of structures would be the most suitable technique to be implemented in Colombia. Desirable features on the fabrication and application of metallic energy dissipators are exposed, and metallic buckling-restrained braces (BRB) dissipators are presented as one viable option for the protection and control for structural damage of buildings in the country. [ABSTRACT FROM AUTHOR]

The paper concerns a research in the sectors of Dressmaking and of Food and Drinks on the impact of the classic techniques of Industrial Engineering in the productivity. Almost 90 chiefs or responsible for this professional area were interviewed. The positive and negative impacts, in accordance with the effect on the company, the workpeople and the clients, are registered. The results show positive effects on productivity and production. also it was found that there is not major opposition from workers and unions. [ABSTRACT FROM AUTHOR]

In this paper we study the consumption pattern, expectations and satisfaction of the population of Medellin with Tetra Pak packages, the treatment given to them now when they are discarded and the conduct to be followed, knowing that the Tetra Pak is recyclable, then the process to recover partially debris from Tetra Pak is modeled and marketed as intermediate goods, eligible to be reinstated within various production processes. Several operating policies through a discrete event simulation built in Extend are studied. [ABSTRACT FROM AUTHOR]

This paper discusses the most important results of a research focused on the construction process of architectonical concrete, presenting as a final result a handbook with recommendations on how to build architectonical concrete elements in the city of Medellin (Colombia). Architectonical concrete is a construction material which is able to supply both structural stability and definitive finishing. The research started by the definition of existing defects as well as their measuring techniques and tolerances. A statistical study was made in order to determine the most common defects on concrete surfaces in Medellin city. Possible causes of the most common defects were determined and, as a result of the analysis of each cause, general and particular solutions were given. General solutions focused on materials, equipment and the building process whereas particular solutions were given to each defect. Finally, the results herein presented constitute an advance in developing a regional specification, which will allow for the standardization of the processes involved on architectonical concrete construction. [ABSTRACT FROM AUTHOR]

This paper is focused on the understanding of the variables and determinants of the ideas about strategy and how to reach it, that were expressed by people who work in companies that are located in the Aburra valley (Medellin, Colombia). The methodology used in the research had an exploratory character, focused on qualitative aspects and was conducted by the completion of a questionnaire with open questions, which final results and observations were afterwards analyzed. After the integration of the results, these were contrasted with recognized authors, such as, Igor Ansoff, Michael Porter, Alfred Chandler, Henry Mintzberg, Richard Whittington, to mention a few, in order to compare the results of the field research with the proposals of such management theory experts. [ABSTRACT FROM AUTHOR]

This paper presents the methodology used to calibrate an NWS-FLDWAV model for flood routing through a stretch of the Medellín river. To build the model, the topographic information of the selected river section was compiled as soon as the stage hydrographs registered in the gauge stations. The importance of considering the discharge contributions along the stretch, which arise from the direct run-off caused essentially by the precipitation, was identified through the analysis of the behavior of the chosen floods. A way to calibrate the model was discovered that included the Manning coefficient of frictional resistance and the contribution discharge. This discharge was obtained from the analysis of the difference between base discharges for the two measurement stations that limit the river segment and were simulated with a spatial and temporal distribution. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present the impact of roads on wildlife and to evaluate the ways to manage these impacts. various foreign articles and studies were analyzed as well as environmental impact studies of roads developed in Antioquia. As a result of this study it was found that the main impacts were roadkills, population isolation, and changes in reproductive patterns. The above impacts have the overall consequence of diminishing the populations of fauna. The management strategies to overcome these impacts are discussed as well. [ABSTRACT FROM AUTHOR]