O estabelecimento de balanços hídricos no campo é difícil e dispendioso, sendo a variabilidade de seus componentes o maior problema para se obter resultados confiáveis. Esta variabilidade dos componentes é aqui apresentada para uma cultura de café desenvolvida no hemisfério sul, em um solo tropical com 10% de declividade. É concluído que a chuva deve ser medida com um número apropriado de repetições, que a irrigação pode introduzir grande variabilidade dos cálculos, que a evapotranspiração calculada a partir da equação do balanço hídrico tem coeficientes de variação muito altos, que o componente armazenamento de água no solo é o que mais contribui na propagação dos erros e que a enxurrada pôde ser satisfatoriamente controlada nesse declive por meio de práticas de manejo. / The establishment of field water balances is difficult and costly, the variability of its components being the major problem to obtain reliable results. This component variability is here presented for a coffee crop grown in the Southern Hemisphere, on a tropical soil with 10% slope. It is concluded that rainfall has to the measured with an appropriate number of replicates, that irrigation can introduce great variability into calculations, that evapotranspiration calculated from the water balance equation has high coefficients of variation, that the soil water storage component is the major contributor in error propagation calculations, and that the run-off could be satisfactorily controlled through crop management practices.

O objetivo do trabalho foi avaliar o impacto de intervenções nutricionais no valor da pegada hídrica do produto leite bovino. O cálculo da pegada hídrica considerou as águas verde, azul e cinza, consumidas no sistema de produção e no beneficiamento do produto. Para determinação dos consumos de água no sistema de produção foram selecionados dois grupos experimentais, cada um contendo sete vacas em lactação. As dietas fornecidas a cada grupo continha os mesmos ingredientes. Porém, na composição do concentrado havia diferentes percentuais proteicos. O concentrado fornecido ao Grupo 1, continha 20% de proteína bruta, e o concentrado fornecido ao Grupo 2, tinha seu teor de proteico ajustado de acordo com a produção de leite do grupo, ao longo da lactação. O ajuste do teor de proteína da dieta as necessidades dos animais promoveu a redução dos consumos das águas verde, azul e cinza e da pegada hídrica do produto leite. A pegada hídrica do Grupo 1 com base no nitrato foi de 503,79 L kg-1 de FPCM (86,1% água verde, 13,4% água azul e 0,43% água cinza) e a do Grupo 2 foi de 452,59 L kg-1 de FPCM (85,3% água verde, 14,3% água azul e 0,45% água cinza). Com base no fósforo, a pegada total do Grupo 1 foi igual a 518,43 L kg-1 de FPCM (83,7% água verde, 13,1% água azul e 3,2% água cinza) e a do Grupo 2 foi de 465,16 L kg-1 de FPCM (83% água verde, 13,9 % água azul e 3,1% água cinza). Entre as três águas, a verde foi a que apresentou maior consumo, atestando a importância da eficiência hídrica na agricultura para os produtos de origem animal. A prática de irrigação das pastagens representou o maior consumo de água azul. O Grupo 2 apresentou melhor eficiência de uso de nutrientes, mas em ambos os grupos as entradas foram maiores que as saídas. O balanço do Grupo 1 foi de 962,7 kg de N, 95,2 kg de P e 545,1 kg de K e do Grupo 2, 869,4 kg de N, 57,8 kg de P, 601,9 kg de K. A captação de água de chuva por cisterna foi avaliada como uma tecnologia hídrica. Essa demonstrou ter impacto positivo na redução do volume de água captado de fonte natural, mas a análise financeira da tecnologia se mostrou inviável para a condição produtiva do estudo. A utilização de intervenções nutricionais que promovam o melhor aproveitamento dos nutrientes pelos animais demonstrou ser uma prática que também contribui para melhoria da eficiência hídrica do sistema de produção e dos produtos de origem animal. Estudos que relacionam o cálculo da pegada hídrica com os aspectos produtivos da pecuária promoverão impactos positivos na conservação dos recursos hídricos e no desempenho dos sistemas de produção. / The aim of the study was to evaluate the impact of nutritional interventions on the dairy milk water footprint. Water footprint calculation considered the green, blue and gray water consumed in the production system and in the dairy unit. To determine the water consumption in the production system was selected two experimental groups with seven lactating cows each. The diets provided to each group contained the same feeds. However, concentrate had different crude protein contents. The concentrate feed Group 1 contained 20% of crude protein, and the concentrate feed Group 2 had its protein content adjusted according to the milk production of the group. The adjustment of the protein content promoted a lower consumption of green, blue and gray water and the reduction of water footprint value. The water footprint based on nitrate in the Group 1 was 503.79 L kg-1 of FPCM (86.1% green water, 13.4% blue water, and 0.43% gray water) and in the Group 2 was 452.59 L kg-1 FPCM (85.3% green water, 14.3% blue water, and 0.45% gray water). Water footprint based on phosphorus was 518.43 L kg-1 of FPCM to Group 1 (83.7% green water, 13.1% blue water, and 3.2% gray water) and to Group 2 was 465.16 L kg-1 of FPCM (83% green water, 13.9% blue water, and 3.1% gray water). Green was the highest volume consumed. This shows the relation between agriculture water efficiency and the water footprint of animal products. Irrigation represented the highest consumption of blue water. The nutrient use efficiency was better to Group 2, but in both groups the inputs were higher than the outputs. The nutrient balance for Group 1 was 962.7 kg N, 95.2 kg P and 545.1 kg K and for Group 2, 869.4 kg N, 57.8 kg P, 601.9 kg of K. Rainwater harvesting in a cistern was evaluated as a water technology. It had a positive impact on reducing the withdraw from ground source, but the economic analysis of the cistern was unfeasible for the productive condition. The use of nutritional interventions for lactating cows promoted better nutrient utilization and has proved to be a management that contributes to the increase of water efficiency in the production system and to animal products. Studies that relate the water footprint with productive aspects of livestock will promote positive impacts on the water conservation and on the performance of production systems.

D. Phil. / Conventional internal wind tunnel balances are designed and constructed to accommodate foil strain gauges which measure the deformation (strain) of the material. Foil strain gauge balances are known to be affected by electromagnetic interference and temperature. These balances are expensive and their manufacture is time consuming. With an increasing demand for higher accuracy, stiffness, increased resolution and temperature compensation, current balance designs are becoming inadequate. To overcome identified balance deficiencies a research programme in the application of optical Bragg gratings to wind tunnel balances was initiated. In this programme a new concept of using optical fibre Bragg grating sensors, with the advantage of using mechanical amplification to increase sensitivity, and the implementation of temperature compensation techniques was demonstrated on a simulated two component balance.

The thesis aims to present an overview of available sources of information for the processing of financial analysis and theoretically defines the main indicators of financial analysis and presents these findings into practice by performing analysis of the company XYZ. Financial analysis is conducted for the period from 2011 to 2015.

En el presente artículo, el autor comenta respecto a la influencia de la contabilidad de las empresas para la determinación de la renta empresarial. En ese sentido, el autor analiza tanto el sistema de Balance único con correcciones que toma la contabilidad como base imponible del impuesto a la renta empresarial  como el sistema de balances independientes no, constituyendo en ese caso únicamente una “base fáctica”. Acto seguido, el autor analiza que sistema resulta ser más conveniente en la realidad peruana.   In this article, the author comments on the influence of corporate accounting for determining corporate income. In this sense, the author discusses both, the unique balance system with corrections which takes accounting as taxable corporate income tax, and the system of independent balances which doesn´t, and only constitute a “factual basis”. Then the author analyzes which system turns out to be more convenient in the Peruvian reality.

The boiler flue gas furnace exit temperature (FET) is a key operating parameter of coal fired steam boilers. From the design perspective, the FET is vital for materials selection and sizing of heat transfer surfaces. From an operating perspective, it is a major indicator of the rate of combustion and heat transfer that is occurring within the furnace. Downstream of the furnace, the FET has a significant impact on both the performance and reliability of the boiler heat exchangers, which ultimately impacts on both boiler efficiency and availability. Monitoring of the FET can advise operating and engineering corrective actions which will ultimately result in better efficiency, reliability and availability together with the associated economic benefits. Therefore, methods of determining FET are investigated. Two methods are focused on for this study, one indirect and one direct. The indirect method studied is a mass and energy balance method which begins with a global boiler mass and energy balance to calculate the major boiler flow rates of coal, air and flue gas which are difficult to measure online. These parameters are then used as inputs into a furnace or backpass mass and energy balance to calculate the furnace exit temperature. The method is applied to a case study, and is evaluated in terms of the measurement uncertainties which are propagated on the intermediate parameters calculated, as well as on the final calculated FET. The main conclusions are that this indirect method contains various uncertainties, due to parameters which have to be assumed such as (i) the distribution of ingress air (also called tramp air) in the different sections of the boiler and (ii) the estimation of the share of water evaporation heat transfer occurring in the water walls of the furnace part of the boiler. The method is however still useful and can be easily applied to any boiler layout and can be used as a reference tool to verify other measurements. The direct method studied is acoustic pyrometry. The work specifically focuses on the sources of error in determining the temperature from the measurement of the time of flight of sound, the impact of particle concentration on the speed of sound through a gas-particle mixture, and the temperature profile reconstruction from acoustic time of flight measurements. A limited set of physical testing was also carried out using one acoustic generator and receiver to take measurements on a real coal power plant. As part of this physical testing, the detection of time of flight from acoustic signals was explored. Already installed radiation pyrometers were also used as a reference for interpreting the acoustic measurements. The indications are that the acoustic pyrometer provides a more representative temperature measurement than the radiation pyrometers. The uncertainty of the acoustic measurement for the same case study as the indirect method was determined and compared with the calculated result. While many aspects still need to be researched further, this initial study and experimental testing produced very promising results for future application of acoustic pyrometry for better monitoring of the coal combustion processes in power plant boilers.

Este trabajo tiene como objetivo realizar un análisis financiero y la valorización de la empresa Corporación Misti SA, dedicada a la venta de fertilizantes diversos para el sector agrícola peruano. La metodología usada se basó en un análisis del entorno del sector agrícola, un breve análisis interno de la empresa; la aplicación del análisis financiero horizontal y vertical, de ratios y finalmente se te estimó un flujo de caja libre para valorizar la empresa usando un escenario actual, uno pesimista y uno optimista, tomando los datos de una empresa internacional líder del rubro como SQM de Chile. Los resultados indican que la empresa Misti tiene activos por 310 millones de soles, 177 millones en pasivos y factura anualmente 535 millones. La rentabilidad medida por el ROA llega a 8% anual, el costo de ventas es de 86% de las ventas, la liquidez medida por el ratio ácido llega a 0.50, mientras que el ciclo de conversión de efectivo es de 191 días. La solvencia a largo plazo ha mejorado pues hay poca deuda de este tipo, sin embargo la empresa tiene 140 millones de pasivos financieros a corto plazo, que han crecido por las mayores ventas (ante mayores inversiones que elevaron su capacidad de almacén en 80 mil tm), pero no ha ganado mucha liquidez debido a las altas cuentas por cobrar. El valor de la empresa Misti considerando sus indicadores financieros actuales y un nivel de crecimiento de ventas que no supere el 2% (menos de la mitad del crecimiento sectorial que llega a 5% anual) llega a 10.60 soles por acción, siendo en total 663.4 millones de soles. Si consideramos que el mercado agrícola no crece, elevamos a 90% el costo de ventas y los gastos operativos suben, entonces el valor de la empresa llega a 5.04 soles por acción, siendo un total de 315. 8 millones de soles por la empresa. Si tenemos una política más eficiente manejando los costos de ventas a 65%, con un crecimiento del mercado de 6.8% a largo plazo y elevando los gastos administrativos y de ventas a 13%, tomando un ciclo de efectivo de 210 días, en todos los casos usando a SQM de Chile como comparador, el valor de la empresa llega a 21.15 soles por acción, en total 1,232.1 millones de soles. El valor por acción es bastante sensible al costo de ventas en primer lugar y a las políticas de gestión del ciclo de efectivo en segundo lugar, claro que si el mercado se reduce habría un efecto negativo, pero ello se mitiga mediante optimización de los inventarios, manejo de las cuentas por cobrar y mejorar los costos operativos al nivel del comparador internacional usado.

Esta investigación titulada “La gestión de inventarios y su impacto en el resultado económico de la empresa Distribuciones Leoncito S.A. del periodo 2016 – 2017”, el cual se planteó como problemática ¿Cómo elaborar una propuesta de gestión de inventarios para obtener un impacto positivo en el resultado económico de la empresa Distribuciones Leoncito S.A. del periodo 2016 – 2017?, para ello se tuvo como objetivo general diseñar una propuesta de gestión de inventarios para obtener un impacto positivo en el resultado económico dentro de la empresa Distribuciones Leoncito S.A. La metodología de la investigación fue de tipo cuantitativo, no experimental de corte transversal, de nivel relacional – causal con propuesta, para lo cual se utilizó como muestra el acervo documentario referido a toda la gestión de inventarios que realiza la empresa, para lo cual se utilizó una guía de análisis documental. Los resultados encontrados determinaron que la gestión de inventarios que realiza la empresa es adecuada, pero a pesar de ello hay ciertos indicadores a mejorar, donde también se pudo hallar que la rentabilidad de la empresa es óptima esto debido a la buena gestión que realiza la empresa. Finalmente se realizó una propuesta para mejorar algunos indicadores que hace que a veces tenga deficiencia en la gestión de existencias, por ello se concluye aceptando la hipótesis de la investigación que fue: El diseñar propuesta de gestión de inventarios permitirá obtener un impacto positivo en el resultado económico de la empresa Distribuciones Leoncito S.A. del periodo 2016 – 2017.

La presente investigación tuvo como objetivo principal analizar la liquidez y la solvencia y su incidencia en la estructura financiera de Conecta Retail S.A. en los años 2013 – 2017, este objetivo nació al observar que los resultados financieros obtenidos en la empresa en estos períodos tenían tendencia a la baja y les estaba ocasionando problemas ante sus stakeholders. Así pues, esta investigación tuvo el propósito de analizar ratios financieras tales como liquidez y solvencia y cómo éstos inciden en la estructura financiera adoptada por Conecta Retail S.A. en los años de estudio planteados. Para el cumplimiento de dicho objetivo la investigación fue de enfoque cuantitativo, tipo de investigación aplicada y diseño no experimental, longitudinal y retrospectivo. En cuanto al primer y segundo objetivo, se halló en Excel y se analizó los ratios de liquidez, solvencia y estructura financiera en los períodos 2013 al 2017 trimestralmente. Posterior a ello, para el tercer objetivo, cada ratio obtenido se codificó dentro del programa SPSS, utilizando un método de modelado, el modelador experto y se complementó éste resultado con la obtención del valor de empresa a partir del EVA. Se concluyó que la liquidez y la solvencia sí incidieron de manera significativa en la estructura financiera, en un 98.40%. Asimismo, el valor de empresa obtenido a partir del EVA mostró que la empresa perdió valor es estos períodos, la liquidez y la solvencia contribuyeron a este resultado desfavorable pues inciden directamente en la estructura financiera.

After the extension of the boiler 6 at Högdalenverket during 2010, there has been some problems in the form of increased carbon monoxide levels. There may be several explanations for this problem, which means that complete combustion doesent take place. There have also been problems with the ash-handling system and the sand returning systemt, this results in higher operating costs because it requires a higher consumption of inert material.The project was first divided into two phases, the first phase was to develop material and energy balances for the boiler but also introduce the parameters that we wanted to investigate further in order to possibly identify the causes of the problems that the boiler had. In the second phase experiments were going to be designed in consultation with the contact staff at Fortum to explore these parameters.During the project changes have been made in the project description, as it will require more time and more accurate planning to perform  the desired tests on the boiler. Three proposals on parameters that could be the cause of carbon monoxide problem was presented at the end of phase one and it was found that two of the proposals was not possible to carry out during the project because it would have affected economically and the availibility of the boilier.The third parameter, the bed quality effect on combustion experiment was designed in consultation with those responsible at Fortum.This experiment could also not be performed as there was some operational difficulties with the boiler during the project time. Instead, a description of the design for the experiment has been added to this project, which may at a later stage be used to investigate the bed quality impact on the carbon monoxide issues.Recent changes to the project description meant that purpose instead was to further develop the computational program created during the project's first phase and at the end of the project shall be submitted to the operators at Fortum. This calculation program takes into account the significant parameters that the boiler regulator is governed by today. The simulation program is developed using Microsoft Excel and is based on material and energy balances. This program can be used internally by Fortum to get an idea of ​​how the different mass flow rates would vary at different operating conditions and how the energy balance for the boiler would look like during the changes.When compared with materials and energy made by the boiler supplier revealed that the deviations are very small compared to what the program come up with and is caused mainly due to the assumptions made. These assumptions can be eliminated by performing experiments and collecting more data.The results gained by the calculation program has been compared with the results that was presented by the supplier during their boiler mapping, comparisons have been made regarding flue gas flows, fuel flows, combustion air flow, ash production and energy balances. It has apperad that the deviations are relatively small and the presented scheme provides a theoretical overall perspective of the boiler in line with reality.Although discussions have taken into consideration for the problem of elevated levels of carbon monoxide, and whether the measurement program can be developed further in the future. / Efter ombyggnationen av panna 6 vid Högdalenverket under år 2010, har det uppkommit en del problem i form av förhöjd kolmonoxid halt. Det kan finnas ett flertal förklaringar till problemet som innebär att fullständig förbränning inte sker. Det har även varit problem med askhanteringssystemet och sandåterföringen som inte fungerat som den ska, detta medför högre driftkostnader då det kräver en högre förbrukning av inertmaterial.   Projektet var indelat i två faser, där den första fasen var att ta fram material- och energibalanser på pannan men också presentera de parametrar som man ville undersöka vidare för att möjligen identifiera orsakerna till de problem som pannan haft.  I den andra fasen skulle experiment utformas i samråd med ansvariga från Fortum för att undersöka dessa parametrar. Under projektets gång har ändringar fått göras på projektbeskrivningen, då det krävs mer tid och noggrannare planering för att utföra test på pannan. Tre förslag på parametrar som kunde vara orsaken för CO problemen presenterades i slutet av fas ett och det konstaterades att två av förslagen inte gick att utföra under projektets gång på grund av både ekonomiska och driftrelaterade orsaker. Den tredje parametern bädd kvaliténs påverkan på förbränningen bestämdes i samråd med ansvariga i Fortum att utföras. Detta experiment kunde dock inte utföras då det uppstod vissa driftrelaterade svårigheter med pannan under projektets gång. Istället har en beskrivning av utförandet av experimentet lagts till detta projekt, som kan vid ett senare skede användas för att undersöka bädd kvaliténs påverkan på CO-halten. Nya ändringar av projektbeskrivningen innebar att syftet istället blev att vidareutveckla det beräkningsprogram som skapats under projektets första fas och som vid projektets slut ska överlämnas till de driftansvariga på Fortum. Detta beräkningsprogram tar hänsyn till de betydande parametrar som pannan regleras genom idag. Beräkningsprogrammet är framtaget med hjälp av Microsoft Excel och är grundat på material- och energibalanser. Detta program kan användas internt inom Fortum för att få en fingervisning på hur de olika massflödena skulle variera vid olika driftfall samt hur energibalansen för pannan då skulle se ut.   Vid jämförelse med material- och energibalans som gjorts av pannleverantören framgick det att avvikelserna är väldigt små jämfört med det vi framtagit, samt att det beror främst på de antaganden som gjorts. Dessa antaganden kan elimineras genom att utföra experiment och få in mer data. Resultatet som fåtts av beräkningsprogrammet har jämförts med det resultat pannleverantören fick vid sin pannkartering med hänsyn till rökgasflöde, bränsleflöden, förbränningsluft flöde, askproduktion och energibalanser. Det har framkommit att avvikelserna är relativt små och det framtagna programmet ger ett teoretiskt helhetsperspektiv av pannan som överensstämmer med verkligheten. Även diskussioner har förts till åtgärder för problemet med förhöjda halter av kolmonoxid, samt huruvida beräkningsprogrammet kan vidareutvecklas i framtiden.