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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.
1

A comparison of commissioning savings determination methodologies and the persistence of commissioning savings in three buildings

Engan, Kenneth Paul 15 May 2009 (has links)
This thesis compares the variability of commissioning savings and the persistence of savings from the Normalized Annual Consumption (NAC) and standard International Performance Measurement and Verification Protocol (IPMVP) weather normalization approaches and from Option C and Option D of the IPMVP. Twenty-nine different weather years were used to obtain a set of savings results under each method. Variability of savings was quantified by the average standard deviation of the 29 percent savings results across all post-commissioning periods for each method. For the combined chilled and hot water savings, the average standard deviation is 0.39% savings for Option D using the NAC weather normalization approach, 0.57% savings for Option D using the standard IPMVP weather normalization approach, 0.71% savings for Option C with regression models using the NAC weather normalization approach, and 0.98% savings for Option C with regression models using the standard IPMVP weather normalization approach. The variability of savings persistence results deviate a little from variability of savings results. For the combined chilled and hot water persistence of savings, the average standard deviation across all post-commissioning periods is 0.48% persistence for Option D using the NAC weather normalization approach, 0.55% persistence for Option D using the standard IPMVP weather normalization approach, 0.52% persistence for Option C with regression models using the NAC weather normalization approach, and 1.26% persistence for Option C with regression models using the standard IPMVP weather normalization approach. Overall, the NAC weather normalization approach shows less variability in savings and persistence than the standard IPMVP weather normalization approach. Additionally, Option D of the IPMVP generally shows less variability in savings and persistence of savings than Option C with regression models. This thesis also determines the savings and persistence of savings from commissioning for three Texas A&M University buildings. Aggregate site savings averaged 11.4%, 16.5%, and 19.0% for the three buildings over differing periods of available data. Persistence results for the three buildings are quite favorable, as each building shows an increase in aggregate site savings between the first and last post-commissioning periods. Follow-up commissioning restored and prevented degradation of savings in two of the buildings.
2

The Persistence of Retro-commissioning Savings in Ten University Buildings

Toole, Cory Dawson 2010 May 1900 (has links)
This study evaluated how well energy savings persisted over time in ten university buildings that had undergone retro-commissioning in 1996. The savings achieved immediately following retro-commissioning and in three subsequent years were documented in a previous study (Cho 2002). The current study expanded on this previous study by evaluating the performance of each building over nine additional years. Follow up retro-commissioning work performed in each building during that time was documented, as well as changes to the energy management control system. Savings were determined in accordance with the methodology outlined in the International Performance Measurement and Verification Protocol (IPMVP 2007), with ASHRAE Guideline 14 also serving as a reference. Total annualized savings for all buildings in 1997 (the year just after retro-commissioning) were 45(plus or minus 2)% for chilled water, 67(plus or minue 2)% for hot water, and 12% for electricity. Combining consumption from the most recent year for each building with valid energy consumption data showed a total savings of 39(plus or minus 1)% for chilled water, 64(plus or minus 2)% for heating water, and 22% for electricity. Uncertainty values were calculated in accordance with methodology in the IPMVP and ASHRAE Guideline 14, and were reported at the 90% confidence interval. The most recent year of data for most of the buildings was 2008-2009, although a few of the buildings did not have valid consumption data for that year. Follow up work performed in the buildings, lighting retrofits, and building metering changes beginning in 2005 were the major issues believed to have contributed to the high level of savings persistence in later years. When persistence trends were evaluated with adjustment for these factors, average savings for the buildings studied were found to degrade over time, and exponential models were developed to describe this degradation. The study concluded that on average energy savings after retro-commissioning will degrade over time in a way that can be modeled exponentially. It was also concluded that high levels of savings persistence can be achieved through performing retro-commissioning follow up, particularly when significant increases are observed in metered energy consumption data, but also at other times as retro-commissioning procedures and technology continually improve.
3

Virtual Commissioning : Virtual Commissioning of ABB Production cell

Lundström, Viktoria January 2016 (has links)
The background of the concept, ABB Production Cell, meets the increasing demands from manufacturing industries throughout the world to simplify through standardization and by that reduce investment cost and operating cost throughout the entire lifecycle of the production cell. ABB is delivering the production cell as one easy to order, use, and maintain. The production cell is developed for virtual versions and full scale production cells. The different modules shall be utilized and presented in RobotStudio and configured in Automation Builder. With generic templates and hardware it provides e.g. early visualization, standardized systems, shortened design/development phase, and enable virtual FAT(Factory Acceptance Test). There is multiple ways of doing a virtual commissioning and it’s a known approach for testing software and hardware together. The method used in this project is known as SIL (Software-In-The-Loop).  This means that the hardware runs as software- e.g. PLC, Drives and HMI- with same properties and behavior as the real hardware. This thesis focus on describing phases of an automation system and see how different phases are affected by a virtual commissioning. Benefits will be described and the existing software will be evaluated. Furthermore, an attempt of virtual commissioning has been done with focus on connecting the software for stable communication with the virtual PLC and make a PLC-task with a handshake to the robot controller and the virtual environment. The system is tested in a virtual environment with vFAT and then on the workshop (FAT). This was done to see if the softwares replicated the same behavior as the hardwares.  The result for the virtual commissioning is that it is possible to run the virtual PLC (VAC500) with the same time interface, behavior, and signals as the real PLC (AC500). / Bakgrunden till konceptet ABB Produktions Cell är ökad efterfrågan av ett enkelt sätt, genom standardisering, att reducera kostnaderna för hela livscykeln för en produktions cell. ABB Produktions cell ska vara enkel att köpa, använda och upprätthålla. Konceptet är utvecklat för att kunna skapa fullskaliga modeller av produktionsceller. Utrustningen och den virtuella miljön finns i RobotStudio och konfigurationen av HMI,Drives och PLC i AutomationBuilder.  Generiska mallar, mjukvaror, hårdvaror ger möjlighet för t.ex. tidig visualisering, förkortad design och utvecklingsfas, standardiserade system samt tidig verifiering och test genom virtuell FAT(Factory Acceptance Test)   Idrifttagning av ett automationssystem kan tillämpas både virtuellt och traditionellt. Det finns flera olika metoder för virtuell idrifttagning och metoden för detta projekt är SIL(Software-In-the-Loop). Detta går ut på att hårdvaror såsom HMI, PLC och Drives körs som mjukvaror, med samma beteende och egenskaper(tidsgränssnitt) som de riktiga hårdvarorna. Den här uppsatsen fokuserar på att beskriva de olika delarna av ett automationsprojekt och hur de påverkas av virtuell idrifttagning. Fördelar med metoden tas fram och den befintliga utrustningen utvärderas. Ett försök till virtuell idrifttagning har genomförts där fokus varit att skapa en sekvenskod för logiken till en befintlig produktionscell samt skapa kopplingar mellan mjukvarorna. Detta testas och verifieras först i virtuell miljö med virtuell FAT(Factory Acceptance Test) och därefter har den verkliga produktionscellen verifierats i verkstaden(FAT). Utvärdering om beteende och cykeltider har också gjorts för att dra slutsatsen om vFAT kan jämföras med FAT under utvecklingsstadiet. Resultatet för den virtuella idrifttagningen är att det är möjligt att köra virtuell PLC(VAC500) med samma tidsinterface, beteende och signaler som den riktiga PLC(AC500).
4

An assessment of quality management practices in low cost housing projects delivery in Mpumalanga province.

Mkhonto, Jobe. January 2014 (has links)
M. Tech. Construction Management / Access to housing and safe accommodation is an integral part of South African government's commitment to poverty relief and the improvement of well being of people. The delivery of low and middle income residential houses has nevertheless not kept up with the growing number of households making up an increasingly impoverished urban housing backlog in South Africa. Beneficiaries are often unhappy about the quality of the structures they have received. The aim of this research study is to assess the factors contributing to poor quality management practices in low-cost housing projects delivery.
5

A Study of Predicted Energy Savings and Sensitivity Analysis

Yang, Ying 16 December 2013 (has links)
The sensitivity of the important inputs and the savings prediction function reliability for the WinAM 4.3 software is studied in this research. WinAM was developed by the Continuous Commissioning (CC) group in the Energy Systems Laboratory at Texas A&M University. For the sensitivity analysis task, fourteen inputs are studied by adjusting one input at a time within ± 30% compared with its baseline. The Single Duct Variable Air Volume (SDVAV) system with and without the economizer has been applied to the square zone model. Mean Bias Error (MBE) and Influence Coefficient (IC) have been selected as the statistical methods to analyze the outputs that are obtained from WinAM 4.3. For the saving prediction reliability analysis task, eleven Continuous Commissioning projects have been selected. After reviewing each project, seven of the eleven have been chosen. The measured energy consumption data for the seven projects is compared with the simulated energy consumption data that has been obtained from WinAM 4.3. Normalization Mean Bias Error (NMBE) and Coefficient of Variation of the Root Mean Squared Error (CV (RMSE)) statistical methods have been used to analyze the results from real measured data and simulated data. Highly sensitive parameters for each energy resource of the system with the economizer and the system without the economizer have been generated in the sensitivity analysis task. The main result of the savings prediction reliability analysis is that calibration improves the model’s quality. It also improves the predicted energy savings results compared with the results generated from the uncalibrated model.
6

The development and testing of an automated building commissioning anlaysis tool (abcat)

Curtin, Jonathan M. 15 May 2009 (has links)
More than $18 billion of energy is wasted annually in the U.S. commercial building sector. Retro-Commissioning services have proven to be successful with relatively short payback times, but tools that support the commissioning effort in maintaining the optimal energy performance in a building are just not readily available. The current work in the field of fault detection and diagnostics of HVAC systems, its cost, complexity and reliance on improved sensor technology, will require years until it can become the mainstay in building energy management. In the meantime, a simplified system is needed today that can be robust and universal enough to use in most types of buildings, address the main concerns of building owners by focusing on consumption deviations that significantly affect the bottom line and provide them some assistance in the remediation of these problems. This thesis presents the results of the development and testing of an advanced prototype of the Automated Building Commissioning Analysis Tool (ABCAT), which has detected three significant energy consumption deviations through four live building implementations. The ABCAT has also demonstrated additional functional benefits of tracking the savings due to retro-commissioning efforts, verifying billed utility data in addition to its primary function of detecting significant consumption faults. Although similar attempts have been made in FDD at the whole building level, the simplification, flexibility, robustness and benefits of this new approach are expected to exhibit the characteristics that will be desired and desperately needed by industry professionals.
7

The development and testing of an automated building commissioning anlaysis tool (abcat)

Curtin, Jonathan M. 15 May 2009 (has links)
More than $18 billion of energy is wasted annually in the U.S. commercial building sector. Retro-Commissioning services have proven to be successful with relatively short payback times, but tools that support the commissioning effort in maintaining the optimal energy performance in a building are just not readily available. The current work in the field of fault detection and diagnostics of HVAC systems, its cost, complexity and reliance on improved sensor technology, will require years until it can become the mainstay in building energy management. In the meantime, a simplified system is needed today that can be robust and universal enough to use in most types of buildings, address the main concerns of building owners by focusing on consumption deviations that significantly affect the bottom line and provide them some assistance in the remediation of these problems. This thesis presents the results of the development and testing of an advanced prototype of the Automated Building Commissioning Analysis Tool (ABCAT), which has detected three significant energy consumption deviations through four live building implementations. The ABCAT has also demonstrated additional functional benefits of tracking the savings due to retro-commissioning efforts, verifying billed utility data in addition to its primary function of detecting significant consumption faults. Although similar attempts have been made in FDD at the whole building level, the simplification, flexibility, robustness and benefits of this new approach are expected to exhibit the characteristics that will be desired and desperately needed by industry professionals.
8

BEMS-assisted Commissioning of HVAC System Energy Conservation Designs

Chen, Lin-Hung 20 July 2008 (has links)
In recent years, Green Building Promotion program has made a significant progress where 1359 cases have acquired the Green Building Candidate Certificate. Among them, 245 cases or 18% in total, eventually received the Green Building Label which is considered low and need to be improved. On the other hand, in United States where LEED is applied, the Commissioning, abbreviated as Commissioning, has been deemed as a Pre-Requisite Requirement for all LEED Projects. In ASHRAE design guides, Commissioning has been defined as a procedure through testing, adjusting, and balancing, to Perform in Conformity with the Design Intent. The goals of Owners, designers, and engineering contractors can all be integrated and optimized where design intent can be fulfilled with traceable records during the Commissioning process. Though Testing, Adjusting, Balancing, and Commissioning, building energy efficiency can be upgraded where energy savings and CO2 emission reduction can be obtained.
9

Maintaining Professional Identity and Role in the Modern Workplace

Fitzgerald, Martin January 2014 (has links)
yes / In the last decade, occupational therapists have faced new performance and commissioning demands from the state. These demands, such as Payment by Results (PbR) or funding tied to performance, have, on the face of it, improved service delivery and patient experience. However, they have also introduced new ways of working and new demands from management that have contributed to a crisis of identity, as therapists struggle to reconcile conflict- ing professional, managerial, and service demands with their day-to-day practice (Lloyd et al 2010). Professionals possess a unique and complex body of knowledge that cannot easily be appreciated and under- stood by those outside the profession. This body of knowledge, along with autonomy and self-regulation, are regarded as important aspects of professionalism and professional identity. However, it is now customary for occupational therapists to work as lone professionals within multi-disciplinary teams, often with professionals of other disciplines as their line or service managers, thereby experiencing differing local management and variant local practice.
10

Komunikační technologi ZigBee v automatizaci budov / ZigBee in Building Automation

Liška, Radovan January 2011 (has links)
Improvement of wireless technologies is a natural consequence of the progress in the field of science and technology. Usage of wireless networks based on the ZigBee technology, which are capable of indepent operation in present form, providing detailed information about physical environment and process management, brings many advantages. On the other hand, there is a serious issue about commissioning. This Master's Thesis deals with introduction of ZigBee technology and its usage, describes issue about device commissioning and types of commissioning. The main part of the Thesis is my own proposal for solving this problem, proposing algorithm using the Bitcloud stack for Coordinator, End Device and Router and its demonstration at the application. Along with analysing the application there are described possible solutions for creating a new network, adding a new node into the existing network and changing a node. The result is a graphical application and firmware for each device. The result of succesfully associated devices in network is supported by the measurement.

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