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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.
11

Flexible company on rapidly changing market - Case study of HMS Industrial Networks

Pliszka, Sylwia, Olijarczyk, Slawomir, Iweins, François-Pascal January 2007 (has links)
<p>This paper is structured to answer the question why it is significant to be flexible on the market and also how to become a flexible company. To create cognitive perception of this issue, analyse of flexible company - an example of still prospering, a leader company HMS Industrial Network, is presented.</p>
12

Flexible company on rapidly changing market - Case study of HMS Industrial Networks

Pliszka, Sylwia, Olijarczyk, Slawomir, Iweins, François-Pascal January 2007 (has links)
This paper is structured to answer the question why it is significant to be flexible on the market and also how to become a flexible company. To create cognitive perception of this issue, analyse of flexible company - an example of still prospering, a leader company HMS Industrial Network, is presented.
13

Ökad flexibilitet i Anybus X-gateway med hjälp av Lua

Håkansson, Jesper, Hansson, Jimmie January 2012 (has links)
HMS Networks AB develops, produces and sells communication technology for industrial automation. The product handles communication between a variety of protocols. The product treated in this project is an Anybus X-gateway Modbus-TCP Master/Client and this module is currently configured from a web-based interface. In doing so, the flexibility for handling protocols is limited to what the company chooses to add to the interface. Therefore the company had a request that the flexibility should be extended using a script language. The project has mainly consisted of two parts. The first part deals with the implementation of the script language Lua and the second part is about measurement and evaluation of the time required for the script. A prototype was developed with an operational implementation and successful results for data transmission. Although it was a successful project some optimizations are required if this solution is to replace the existing one, because script languages are not as fast as C. Some knowledge in programming and network is required to obtain an adequate understanding of the report.
14

Development of macro/nanocellular foams in polymer nanocomposites

Bhattacharya, Subhendu, subhendu.bhattacharya@rmit.edu.au January 2009 (has links)
This thesis focuses on the generation of fine cell polymer foams using a heterogeneous nucleating agent (nanoclay), appropriate polymer blending strategies and accurate control of foam processing parameters. Foaming behaviour of HMSPP/ clay nanocomposites and HMS-PP/EVA/clay nanocomposite blends is studied using a batch and a continuous foam injection moulding system. Morphological studies using TEM and SEM led to a few interesting deductions. It is very difficult to attain complete exfoliation in case of HMS-PP/clay nanocomposites even at low clay loadings due to a non polar nature and low graft efficiencies of HMS-PP matrix. The addition of clay to an immiscible blend of HMS-PP/EVA results in compatibilization between the dispersed and the continuous phase. Nanocellular foams (290 nm) were subsequently generated in the batch process at a foaming temperature of 147oC and 25 seconds foaming time. The addition of immiscible EVA-28 to the HMS-PP matrix in presence of clay particles further results in reduction of foam cell sizes to 100 nm. The effect of gas concentration, foaming temperature, injection pressure, and foaming time on foam cell size was studied. It was found that the foam cell size was highly sensitive to the injection pressure at the mould gate (hence pressure drop rate) and foaming temperature. The cell size linearly decreased with increase in gas concentration and foaming time. The sensitivity of foam cell sizes to changes in processing parameters decreases with increase in clay concentration. The effect of addition of clay particle on gas solubility was modelled using the Guggenheims contact fraction approach and subsequently a new model to predict gas solubility was developed using statistical thermodynamic tools. Additionally the effect of shear and extensional rheology on foam cell morphology was modelled. It was found that the viscoelasticity of the polymer matrix greatly affects cell sizes as compared to extensional viscosity.
15

Development process for distributed automation systems based on elementary mechatronic functions

Panjaitan, Seno Darmawan January 2007 (has links)
Zugl.: Kaiserslautern, Techn. Univ., Diss., 2007
16

ANALYZING THE EFFECTS OF CLIMATE CHANGE ON URBAN STORMWATER INFRASTUCTURES

Thakali, Ranjeet 01 May 2017 (has links)
The change in the hydrological cycle due to climate change entails more frequent and intense rainfall. As a result, urban water systems will be disproportionately affected by the climate change, especially in such urban areas as Las Vegas, which concentrates its population, infrastructure, and economic activity. Understanding the proper management of urban stormwater in the changing climate is becoming a critical concern to the water resources managers. Proper design and management of stormwater facilities are needed to attenuate the severe effects of extreme rainfall events. In an effort to develop better management techniques and understanding the probable future scenario, this study used the high-resolution climate model data conjunction with advanced statistical methods and computer simulation. Las Vegas Valley which has unique climatic condition and is surrounded by the mountains in every direction was chosen for the study. The North American Regional Climate Change Assessment Program is developing multiple high-resolution projected-climate data from different combinations of regional climate models and global climate models. First, the future design depths was calculated using generalized extreme value method with the aid of L-moment regionalization technique. The projected climate change was incorporated into the model at the 100 year return period with 6h duration depths. Calculation showed that, the projection from different sets of climate model combinations varied substantially. Gridded reanalysis data were used to assess the performance of the climate models. This study used an existing Hydrologic Engineering Center’s Hydrological Modeling System (HEC-HMS) model and Storm Water Management Model (SWMM) developed by the Environmental Protection Agency (EPA) were implemented in the hydrological simulation. Hydrological simulation using HEC-HMS showed exceedances of existing stormwater facilities that were designed under the assumption of stationarity design depth. Low Impact Developments such as permeable pavement and green roof were found to be effective in the attenuation of climate change induced excess surface runoff. The primary purpose of this study is understanding of proper designing, planning and management of the urban stormwater system in the predicted climate scenarios.
17

AVALIAÇÃO DE VAZÕES MÁXIMAS ESTIMADAS A PARTIR DOS MODELOS HEC-HMS E SWMM ESTUDO DE CASO PARA O NÚCLEO URBANO E REGIÃO PERIURBANA DE MUNIZ FREIRE

SOUZA, T. C. T. 04 August 2017 (has links)
Made available in DSpace on 2018-08-01T23:59:24Z (GMT). No. of bitstreams: 1 tese_11471_Dissertac&#807;a&#771;o - Tainah de Souza CD.pdf: 4931542 bytes, checksum: fab9c37691c8c2445e4f9540b0310b3e (MD5) Previous issue date: 2017-08-04 / A determinação da vazão de projeto constitui etapa fundamental para o adequado dimensionamento de obras de drenagem ou para possibilitar a adequada tomada de decisão sobre medidas não estruturais relacionadas com a drenagem pluvial. Em regiões que não dispõem de dados fluviométricos recorre-se, usualmente, à utilização dos modelos do tipo chuva-vazão para determinação indireta da vazão de projeto. Função da diversidade de modelos disponíveis, cabe ao modelador a escolha do modelo mais adequado às singularidades da área avaliada, permitindo a produção de resultados que se apresentem mais próximos da realidade. Neste estudo foi realizada a análise comparativa dos modelos Storm Water Management Model (SWMM) e Hydrologic Engineering Center - Hydrologic Modeling System (HEC-HMS) quando da estimativa de vazões máximas associadas ao núcleo urbano e regiões periurbanas do município de Muniz Freire (ES). A estimativa do escoamento superficial foi realizada através do método Hidrograma Unitário e as perdas de infiltração pelo método SCS Curve Number. A equação de chuvas intensas foi apropriada através do método de Chow-Gumbel e a chuva de projeto pelo método dos blocos alternados. Os modelos apresentaram relevantes diferenças nos valores de vazão de pico e volume de escoamento superficial. Para períodos de retorno entre 2 e 5 anos, os valores de vazão de pico e volumes de escoamento superficial estimados pelo SWMM apresentaram-se superiores aos obtidos pelo HEC-HMS para todas as bacias avaliadas, invertendo-se esta tendência com o aumento do período de retorno. As simulações associadas aos períodos de recorrência de 10 e 20 anos, usualmente utilizados em estudos e projetos de drenagem urbana, foram as que se apresentaram mais próximas, com as menores diferenças relativas para as variáveis hidrológicas avaliadas.
18

Assessing the ability of HEC-HMS rainfall-runoff model to simulate stream flow across Sweden

Alavimoghaddam, Mohammadreza January 2017 (has links)
Computer modeling is the powerful tool for simulating nature’s behavior; however, still more efforts are need for reaching perfect simulation with computer models (especially in the hydrological field of study). In this Master’s thesis, the accuracy of the HEC-HMS computer model for long term rainfall-runoff simulation was evaluated across Sweden. Five different catchments from north to south of Sweden were selected and then simulation have done for 34 years of available data. Simulation was conducted using daily, monthly and yearly time scale resolutions. Results from the north to the south of Sweden were completely different. Simulated runoff and observed runoff in northern catchments followed the same pattern over different time scales but in the southern part of Sweden the results had different patterns in space and time. The best results with HEC-HMS were found in the northern catchments with steep main river slopes. In the southern catchments the model could not predict runoff in any realistic manner at any time and space scale. In total the HEC-HMS model cannot simulate the rainfall runoff for long periods of simulation across Sweden. This is especially true in southern parts of the country dominate with low elevation catchments. However, with regards to its ability for event-based simulation HEC-HMS could be a suitable tool to simulate flood event discharges that are needed for road or other hydraulic structures designs. But, this would require significant amounts of calibration and model development.
19

Distributed storage modeling in Soap Creek for flood control and agricultural practices

Wunsch, Matthew John 01 May 2013 (has links)
In 1988, the counties of Appanoose, Davis, Monroe, and Wapello created the Soap Creek Watershed Board. This group put in place a plan to fund and construct 154 farm ponds in an effort to provide water for agriculture practices as well as provide flood protection for the residents inside the Soap Creek watershed. Through collaborative efforts and funding from federal, state, and local sources, to date 132 ponds have been constructed. Currently there is no stream monitoring in place in the watershed to observe stream conditions. This leads to no stored data on the benefits of the projects in the basin and the reduced flood impacts. With funding from the Iowa Watershed Projects (IWP) through the IIHR - Hydroscience & Engineering lab, a lumped parameter surface water model was created to show the benefits of the constructed projects. Using detailed LiDAR data, a Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) model was created. This model used arcHydro and ARC-GeoHMS, tools in ARCgis. Detailed LiDAR, SURGGO soil data, and land cover data was used to create the model parameters. Several design and historical storms were modeled to quantify the benefits in peak flow reductions and in amounts of water stored behind the projects.
20

Modeling Flood Reduction Scenarios for a Small Coastal Community

Perez, Evan J. 01 March 2013 (has links) (PDF)
The Arroyo Grande Creek Watershed, an approximately 170 mi2 watershed located on the central coast of California, drains to the Pacific Ocean via the Arroyo Grande Creek that passes through several coastal cities including the community of Oceano. At the mouth of the Creek is the Arroyo Grande Lagoon, which is connected to another lagoon known as the Oceano Lagoon, by a tidal flap-gate whose hydraulics is a function of water levels in the two lagoons. Historically the Oceano Lagoon has played a part in floods that have occurred in the community of Oceano. The most recent flooding occurred in 2010 when a storm with about a10-yr frequency caused flooding that led to an estimated property damage of about two million dollars. This study was conducted to understand hydrology of the Arroyo Grande watershed that also feeds Lopez Lake, a reservoir that provides water for drinking, agriculture, and environmental flows; to characterize hydraulics of the Oceano Lagoon; and to explore scenarios for flood mitigation. Objectives of the study are to provide a better understanding of the causes of the historical floodings; map the extent of floodings for various storm events including 10 year, 50 year, and 100 year under current conditions; and examine potential solutions to reduce future floodings. Surface water hydrology of the Arroyo Grande Creek Watershed was studied using HEC-HMS to quantify runoff specifically into the Oceano Lagoon. HEC-HMS was calibrated using known streamflow to improve the accuracy of the model. The HEC-HMS model was developed using spatial data that was organized in ArcMAP. Data such as elevation, land use, soil type, and impervious surface were processed using HEC-GeoHMS and exported to HEC-HMS. Mitigation measures were simulated in HEC-HMS by adjusting parameters such as the outlet configuration and the increased volume in Oceano Lagoon. Each mitigation measure delivered varying effectiveness. Results show that while the peak flow and volume in the lagoon can be reduced, larger design storms will continue to inundate the area unless drastic steps are taken. The findings could assist local flood control agencies by evaluating the risks of continuing to use the existing drainage system, and identifying opportunities available to reduce those risks.

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