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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

Production process optimization model to increase productivity of microenterprises in the industrial chemical sector using 5s and tpm

Chancahuana-Palomino, Leonardo, Ortiz-Licas, Alondra, Altamirano-Flores, Ernesto, Aderhold, Daniel 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / The industrial chemical sector has grown during the last years in the Peruvian market, becoming highly competitive since it represents the second main activity in the manufacturing industry. However, companies belonging to the sector have experienced a decrease in productivity, since it has a lower production rate than other economic sectors. This paper presents a model for increasing the productivity of companies in the sector. For this, the 5S and TPM techniques will be used sequentially. First, 5S techniques are applied to reorder the working area and to create a clean and safe environment for operating personnel. Then, the TPM technique is used to focus on reducing the deficiencies that machines present through preventive maintenance and raise awareness and involve operational personnel in the daily activities of autonomous maintenance. For validation of the model, a simulation with the software Arena is performed. Results show an increase of about 15% in productivity, the cycle time reduces by 14%, the OEE will increase by 24% and daily production by 15% in the paint line.
492

Management model for the improvement of logistics productivity in pecan producing MSEs in Ica / Modelo de gestión para la mejora de productividad logística en Mypes productoras de pecana en Ica

Perlacios, Edward, Astete, Alexandra, Sotelo, Fernando, Raymundo, Carlos, Dominguez, Francisco 01 January 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / El propósito de este documento de investigación es proponer un modelo de gestión logística en Mypes productoras de pecana ubicadas en el departamento de Ica, Perú, para esto se realizó un censo a un total de 18 huertos. Este estudio analiza el ámbito de la productividad de las pecanas peruanas en Ica. El modelo es presentado en dos partes: el diagnóstico de las Mypes productoras de pecana en relación al proceso logístico donde se muestran las deficiencias y brechas existentes en comparación con países productores con mayor experiencia y antigüedad en el rubro; así mismo se presenta la propuesta del modelo logístico el cual es desglosado en 3 subprocesos: subproceso de compras, almacenado de materia prima e insumos y almacenado de producto terminado. El desarrollo de los subprocesos se realizó a través de herramientas de gestión por procesos y buenas prácticas logísticas. El principal aporte de la investigación es proponer un modelo en el cual el agricultor pueda adoptar las buenas prácticas, utilizar los indicadores y procedimientos propuestos para tener un control del proceso logístico. El modelo se validó mediante el juicio de expertos y posterior simulación.
493

Productivity analysis of LHD equipment using the multiple linear regression method in an underground mine in Peru

Prudencio, Gerald, Pino, Diego, Arauzo, Luis, Raymundo, Carlos 01 January 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / The current study is based on a multiple linear regression analysis with an objective to formulate an equation related to the productivity analysis of LHD equipment using independent variables such as the effective utilization of the equipment. To identify the independent variables, main productive factors, such as the actual capacity of the buckets, the transport cycles in the cleaning process, and the performance by means of curves, were analyzed. Comparisons of a Peruvian underground mine case study exhibited that the battery-powered equipment denoted similar production efficiencies to that exhibited by its diesel counterparts; however, the three-tier approach observed that the battery-powered equipment could achieve production efficiencies that are up to 13.8% more as compared to that achieved using its diesel counterparts because of increased effective utilization that can be attributed to long MTBF. The results of this study exhibit that LHDs under battery-powered storage are feasible for underground mining not only because of the fact that they do not emit any polluting gases, which helps to mitigate pollution, but also because of their good production performance that can be considered to be an important pillar in deep mining. Copyright 2019.
494

Corporate Social Responsibility and Traffic Congestion: A Mixed Methods Study

Bakare, Bukola January 2020 (has links)
Traffic congestion (TC) is a complex issue having an adverse impact on the environment, business operations and health. Many cities are taking action to curb it. Corporations have increasingly engaged in corporate social responsibility (CSR) actions. Using corporations headquartered in the top-rated traffic congested cities in the United States, this study examines the relationship between TC and CSR. The quantitative research employed a general linear model with two datasets, traffic speed data and CSRHub ratings. The speed data was used to calculate travel time index (TTI), a measure of TC. Using Atlanta BeltLine Inc. as a case study, a phenomenological thematic approach was utilized to assess stakeholders’ viewpoints of congestion mitigation efforts in Atlanta, GA. This study adds to research on CSR by examining the effects that CSR actions have on a specific local event, e.g., TC. In addition, research reflecting on the impact of CSR on TC has not been conducted. This study aims to fill this gap. Of the four areas of CSR studied in the quantitative phase, the community, environment, and governance ratings are significantly related to TTI, with community and environment having an inverse relationship to TTI. The qualitative study showed that stakeholders struggle with TC, and that the relationship between CSR and TC is not obvious to them. This quantitative study was conducted on eighteen top-rated congested cities. Further study on other major congested cities may shed more light on CSR and TC. A future qualitative analysis can explore the viewpoint of city government. Findings in this study are expected to be a leverage point for public-private TC mitigation and to inform policies that incorporate TC reduction as a CSR indicator. Although the quantitative analysis showed that a relationship exists between CSR and TC, the literature and DOT reports revealed increased and continuous congestion in these cities. The case study of the ABI project in the qualitative research indicated that TC is an area where CSR can have a major local impact. Some corporate respondents acknowledged that TC has a business cost, however no serious steps are taken to tackle TC.
495

Optimization of the design process in construction projects by the implementation of the A360 collaboration tool

Arevalo, Jennifer, Palacios, Mauricio, Rodriguez, Sandra, Farje, Julio 30 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Each year there are more construction companies seeking for implementation of the Building Information Modeling (BIM) methodology in their projects since it provides different benefits related to project time, cost and quality. Besides, different countries currently demands its application. However, companies do not always achieve these benefits at its totality because BIM implementation must overcomes a series of difficulties related to interoperability and personnel, difficulties which are generated by a lack of collaboration and communication between the project stakeholders. The present investigation finds a new solution to this problem, reducing the waste generated at the design stage of the BIM projects by implementing the A360 collaboration tool, a platform which provides a virtual centralized space that allows storing BIM files, visualizing them and making comments in real time from any device. The results show a reduction of waste that finally reduce the time for the design stage in a BIM project
496

An Analysis of a Measure of Productivity in Mule Deer Populations

Ryel, Ronald J. 01 May 1980 (has links)
The purpose of this study was to investigate the relationship between the fall proportion of fawns among fawns and does in a mule deer population and two measures of productivity, the spring recruitment rate and the reproductive performance as measured in the fall. The spring recruitment rate was defined to be the number of fawns per doe which were recruited into the population at 1 year of age. The reproductive performance was defined to be the number of fawns produced per doe 2 years or older which survive to a specified time. The relationships between these quantities were measured by calculating linear coefficients of correlation from data generated by a projection matrix model of a mule deer population. A coefficient of correlation of 0.86 was found between the fall proportion of fawns and the rate at which fawns are recruited into the spring population. A coefficient of correlation of 0.89 was found between the fall proportion of fawns and the reproductive performance as measured in the fall. The effect of misclassifying fawns as does and does as fawns on estimates of the proportion of fawns among fawns and does was also investigated. A comparison was made between the expected values of two estimates of the fall proportion, one with misclassification and one without misclassification. The misclassification of fawns and does was found to bias estimates of the proportion of fawns. The bias was found to be a function of the amount of misclassification and the actual proportion of fawns .
497

A Management Study of the Cache Elk Herd

Hancock, Norman V. 01 May 1955 (has links)
American elk, by virtue of their distribution, were the most cosmopolitan members of the cervid family at the time of white settlement of North America. At this early date elk were present in every major region of what is now continental United States, as well as in northern Mexico. they likewise were abundant in upper and lower Canada, though records do Lot corroborate their presence too far north on the Atlantic coast. Although generally existent throughout the western states, elk were sparsely distributed in Nevada, southern Utah, and most of Arizona and New Mexico. Paucity of elk was also noted in eastern portions of Washington and Oregon.
498

The use of track autoradiography to determine species-specific phytoplankton productivity

Vaga, Ralph Martin 01 January 1978 (has links)
Methods of measuring primary productivity are discussed in terms of what information they provide concerning energy flow in the phytoplankton community. A track autoradiographic technique is presented which measures species-specific phytoplankton productivity and its use is demonstrated under laboratory conditions. Controls and standardized processing conditions are established which permit the use of the track technique in quantitative evaluations of primary productivity.
499

Three Essays on the Indian Manufacturing: Wage Inequality, Export and Informality / インド製造業分析に関する論文集-賃金格差、輸出及びインフォーマル性

Furuta, Manabu 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第20147号 / 経博第545号 / 新制||経||280(附属図書館) / 京都大学大学院経済学研究科経済学専攻 / (主査)准教授 遊喜 一洋, 教授 劉 徳強, 教授 神事 直人 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DFAM
500

Environmental and Biotic Processes Influencing Floristic Composition, Quality, Integrity, and Function in Tallgrass Paririe Assemblages

Manning, George 01 August 2018 (has links) (PDF)
Tallgrass prairie is one of the most threatened grasslands in North America. Conservation of tallgrass prairie focuses on both effective management of remaining native prairie, and restoration of formerly cultivated fields to tallgrass prairie. This research focused on processes and properties relevant to restoration and conservation of tallgrass prairie. Community assembly theory attempts to explain the formation of communities, which can be governed by deterministic or stochastic processes, or some combination of both. Fire and grazing are widely used to manage grasslands for conservation purposes, but few studies have evaluated the effects of these drivers on the conservation value of plant communities measured by the floristic quality index (FQI). Pollination services play a vital role in the reproductive stability of the plant community in prairies, though this has not been well studied in restored prairie. The first chapter of this dissertation reports on a sequential restoration approach used to gain insights into the extent to which community assembly is deterministic and stochastic events change the trajectory of community development. The sequential restorations consisted of former agriculture fields restored to prairie, varying only in time since abandonment. Species composition and aboveground net primary production were quantified over time in sequentially restored communities to reveal the predictability of ecological restoration in producing desired communities and ecosystem functions. The sequential restoration plots were established in a block design. The same suite of species was seeded using the same seeding rates in each restoration sequence. Species composition was recorded each September in the year of seeding and each June and September in the two subsequent years for each block. Annual aboveground net primary productivity was collected from 2 randomly placed 0.1 m2 plots per subplot during peak biomass. There was a significant sequence by age interaction for sown, volunteer, and total species composition. Sown, volunteer, and total cover, diversity, and richness also were affected by a sequence by age interaction. Annual net primary production (ANPP) also was affected by a sequence by age interaction for sown and volunteer species. However, total ANPP was only affected by the variable age. Results show that interannual climate variability (specifically growing season precipitation) inhibits a priori determinations of community assembly, which suggests that stochastic processes play a significant role in the community assembly process in tallgrass prairie restoration. Variations in annual precipitation during the installation years likely drove the initial differences in species composition and ANPP. In general this study revealed that drought conditions at the time of restoration may be more deleterious than drought conditions occurring at other times post-establishment. The influence of fire and grazing on soil properties and functions is difficult for land managers and restoration practitioners to assess. Therefore, the objectives for the second study were to (i) to quantify the independent and interactive effects of grazing and fire frequency on floristic quality in native tallgrass prairie, and provide potential benchmarks for community assessment, and (ii) to explore whether floristic quality can serve as an indicator of soil structure and function for more holistic ecosystem assessments. A factorial combination of fire frequencies (1-2, 4, and 20 y return intervals) and grazing (by bison or ungrazed) treatments was sampled for plant species composition and several indicators of soil quality in lowland tallgrass prairie. Floristic quality, diversity, and richness were higher in grazed than ungrazed prairie over all fire frequencies. Available inorganic N, microbial biomass N, total soil N, and soil bulk density were also higher in grazed prairie soil over all fire frequencies. Microbial biomass C, total soil organic C, and total soil N were positively correlated with FQI. This study demonstrated that floristic quality and soil N pools are more strongly influenced by grazing than fire and that floristic quality can be an indicator of total soil C and N stocks in never cultivated lowland prairie. In tallgrass prairie, 85 – 90 % of angiosperms require an insect or other animal for pollen transfer. Restorations can play a vital role in the reestablishment of pollination services and simultaneously help maintain high levels of diversity in the tallgrass prairie ecosystem. Missed pollination, via temporal asynchronies, could have a number of biological disadvantages for a plant population. In the third study we addressed the effects of missed pollination on floral period, photosynthetic activity, leaf N content, and seed set in a common native tallgrass prairie forb, Penstemon digitalis. In each of 12 plots, 6 individual plants were either bagged to prevent pollination, or left unbagged, to allow for pollination. There was no difference in mean flower duration between netted and open plots. There was a treatment by time interaction for relative chlorophyll concentrations (P = 0.0005). Mean relative chlorophyll concentrations values at sampling times (prior to flowering; Pre, 10 days after FFD; Plus, 10 days after cessation of flowering; Post, and at the time of leaf collection; Coll) all differed from one another in bagged plots. Comparisons of relative chlorophyll concentrations values only showed a difference between bagged and open-pollinated plots at sampling time ‘Coll’. There was no difference in percent leaf N between bagged and open-pollinated plots and the amount of seed set in bagged plots was significantly lower than the amount of seed set in the open-pollinated plats. Any disruption to plant-pollinator interactions can create temporal asynchronies, however, the impact of those asynchronies is equivocal.

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