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Assessment of Fire Safety for Intermediate Floors in the New Zealand Acceptable Solution C/AS1Le, Phung Van January 2010 (has links)
This research project aims to investigate the level of risk/safety inherent in intermediate floors of buildings designed to the Compliance Document for the New Zealand Building Code, Fire Safety Clauses C1, C2, C3, C4 (C/AS1), and develop guidance for Fire Engineers on designing fire safety for firecells containing intermediate floors. The project also aims to develop a new set of prescriptive fire safety requirements for intermediate floors and proposes an outline of a verification method for designing fire safety for intermediate floors.
This study includes a literature review of the fire safety requirements for intermediate floors (mezzanines) of prescriptive requirements in New Zealand and other countries such as USA, Canada, UK and Australia. The results of this literature review found that the intermediate floor size is limited and varies with country. An intermediate floor that has an area exceeding the limit set out by the prescriptive requirements is considered as a storey in all the countries prescriptive requirements reviewed including the New Zealand prescriptive requirements prior to 1991. Since 1991, in New Zealand Acceptable Solutions, the intermediate floor that has an area exceeding the limit will not be treated as a storey, however, a smoke control system is required.
The level of risk was quantified using a factor of safety (FoS) - the ratio of Available Safe Egress Time (ASET) to Required Safe Egress Time (RSET). Two fire models; BRANZFIRE and FDS were used to calculate ASET and SIMULEX, an evacuation program, was used to calculate movement times of the occupants of the studied buildings. Unlike the traditional method in which RSET and FoS are assessed using single value, in this project the distribution of RSET and FoS were assessed using the @RISK software package. The analysis showed that the level of risk to the occupants of the firecells containing intermediate floors is always higher than that of the equivalent firecells without intermediate floors with the same occupant load and the differences in FoS range from 10% to 60%. The analysis also highlighted that the level of risk to the occupants of firecells having intermediate floors increases as the intermediate floor size increases, however, there are no clear cut-off points at which a higher level of fire safety precaution should be provided. The cut-off points in C/AS1 of 20% for a closed intermediate floor and 40% for an open intermediate floor, are not justified by this analysis. Occupant load has significant impact on the level of safety of the occupants of the firecells containing intermediate floors. The higher the occupant load the lower the level of safety is.
The definitions for open and closed intermediate floors are proposed to which open and closed intermediate floors are clearly distinguished. The term “limited area intermediate floor” in the current C/AS1 is proposed be removed and all related clauses are proposed to be amended or deleted accordingly. A proposed new set of prescriptive fire safety requirements for intermediate floors has been developed based on the occupant load of intermediate floors and not the intermediate floor size in the form of a table similar to the current Table 4.1 of C/AS1. The occupant load and fire safety precautions (FSPs) of the intermediate floors are determined based on the occupant load and their required FSPs of the equivalent firecells without intermediate floors that have the same factor of safety with the firecells containing intermediate floors. With the proposed FSPs, a firecell with lower occupant load would require lesser fire safety requirements than a firecell with higher occupant load regardless of intermediate floor size. Moreover, with the proposed FSPs for intermediate floors, the level of safety of the occupants of the firecells having intermediate floors would be very similar to the level of safety of the equivalent firecells without intermediate floors. In addition to the proposed tables of FSPs, some clauses regarding the changes in the fire safety requirement and definitions for intermediate floors are proposed.
Guidance for designers in designing fire safety for firecells containing intermediate floors in which the methods of modelling using BRANZFIRE and Fire Dynamics Simulator (FDS) are presented in detail, has been developed. The analysis has pointed out that the location of the exits is critical in designing fire safety for firecells containing intermediate floors and majority of exits from the lower floor should not be located under intermediate floors.
Although one of the main objectives of this research project was to propose an outline of a verification method for designing fire safety for intermediate floors, the analysis showed that it is very difficult to develop a rational verification method for designing fire safety for firecells containing intermediate floors.
Using the proposed FSPs for intermediate floors which are based on the occupant load of the intermediate floors in designing fire safety for firecells containing intermediate floors is recommended by this study. These recommendations do not preclude the use of specific fire engineering design for designing fire safety for firecells having intermediate floors.
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Assessment of variant load in an idiopathic autoinflammatory index patientNordin, Jessika January 2014 (has links)
No description available.
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Utveckling av lastmodell för Uppsala fjärrvärmenät / Development of a load prognosis model for Uppsala district heating systemBuddee, Ingrid January 2014 (has links)
The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends. The outcome was a model that would produce a prognosisfor the heat load for each customer type. The total model for the whole districtheating system was less accurate, but still usable. All models developed are howeverrelying on the quality of the available weather prognosis. The benefit of a precise loadprognosis is to facilitate production planning and optimization. Accurate predictions ofthe heat demand, especially in the case of peak load, will result in better productionplanning and thus cost efficiency.
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Biodiesel production from sunflower oil using microwave assisted transesterification / by Nokuthula E. MagidaMagida, Nokuthula Ethel January 2013 (has links)
Biofuels are becoming more attractive worldwide because of the high energy
demands and the fossil fuel resources that are being depleted. Biodiesel is one of the most
attractive alternative energy sources to petroleum diesel fuel and it is renewable, non toxic,
biodegradable, has low sulphur content and has a high flash point. Biodiesel can be generated
from domestic natural resources such as coconuts, rapeseeds, soybeans, sunflower, and waste
cooking oil through a commonly used method called transesterification. Transesterification is a
reaction whereby oil (e.g. sunflower oil) or fats react with alcohol (e.g. methanol) with or
without the presence of a catalyst (e.g. potassium hydroxide) to form fatty acid alkyl esters
(biodiesel) and glycerol. The high-energy input for biodiesel production remains a concern for the
competitive production of bio-based transportation fuels. However, microwave radiation is a method
that can be used in the production of biodiesel to reduce the reaction time as well as to improve
product yields. Sunflower oil is one of the biodiesel feedstocks that are used in South Africa and
is widely used in cooking and for frying purposes.
This study aims to use microwave irradiation to reduce the energy input for biodiesel production.
The effect of various reaction variables, including reaction time (10 – 60 seconds), microwave
power (300 – 900 watts), catalyst (potassium hydroxide) loading (0.5 – 1.5 wt%) and methanol
to oil molar ratio (1:3 – 1:9) on the yield of fatty acid methyl ester (biodiesel) was
investigated. The quality of biodiesel produced was analysed by Gas Chromatography (GC), Fourier
Transform Infrared Spectroscopy (FTIR) and viscometry. The FTIR results confirmed the
presence of functional groups of the FAME produced during transesterification.
The results showed that transesterification can proceed much faster under microwave
irradiation than when using traditional heating methods. The interaction between the alcohol and
oil molecules is significantly improved, leading to shorter reaction times (seconds instead of
hours) and improved diesel yields. The highest biodiesel yield obtained was 98% at 1:6
oil-to-methanol molar ratio for both 1 wt% and 1.5 wt% potassium hydroxide (KOH) at a reduced
reaction time (30 seconds). The chemical composition of FAME (biodiesel) obtained from different
conditions
i
contained palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) and 70% linoleic acid
(C18:2). The physical properties (cetane number, viscosity, density and FAME content) of biodiesel
produced met the SANS 1935 specification. The energy consumption was reduced from 1.2 kWh with the
traditional transesterification to
0.0067 kWh with the microwave transesterification.
Microwave irradiation was shown to be effective in significantly lowering the energy consumption
for production of biodiesel with good quality for small scale producers. / Thesis (MSc (Engineering Sciences in Chemical Engineering))--North-West University, Potchefstroom Campus, 2013
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Biodiesel production from sunflower oil using microwave assisted transesterification / by Nokuthula E. MagidaMagida, Nokuthula Ethel January 2013 (has links)
Biofuels are becoming more attractive worldwide because of the high energy
demands and the fossil fuel resources that are being depleted. Biodiesel is one of the most
attractive alternative energy sources to petroleum diesel fuel and it is renewable, non toxic,
biodegradable, has low sulphur content and has a high flash point. Biodiesel can be generated
from domestic natural resources such as coconuts, rapeseeds, soybeans, sunflower, and waste
cooking oil through a commonly used method called transesterification. Transesterification is a
reaction whereby oil (e.g. sunflower oil) or fats react with alcohol (e.g. methanol) with or
without the presence of a catalyst (e.g. potassium hydroxide) to form fatty acid alkyl esters
(biodiesel) and glycerol. The high-energy input for biodiesel production remains a concern for the
competitive production of bio-based transportation fuels. However, microwave radiation is a method
that can be used in the production of biodiesel to reduce the reaction time as well as to improve
product yields. Sunflower oil is one of the biodiesel feedstocks that are used in South Africa and
is widely used in cooking and for frying purposes.
This study aims to use microwave irradiation to reduce the energy input for biodiesel production.
The effect of various reaction variables, including reaction time (10 – 60 seconds), microwave
power (300 – 900 watts), catalyst (potassium hydroxide) loading (0.5 – 1.5 wt%) and methanol
to oil molar ratio (1:3 – 1:9) on the yield of fatty acid methyl ester (biodiesel) was
investigated. The quality of biodiesel produced was analysed by Gas Chromatography (GC), Fourier
Transform Infrared Spectroscopy (FTIR) and viscometry. The FTIR results confirmed the
presence of functional groups of the FAME produced during transesterification.
The results showed that transesterification can proceed much faster under microwave
irradiation than when using traditional heating methods. The interaction between the alcohol and
oil molecules is significantly improved, leading to shorter reaction times (seconds instead of
hours) and improved diesel yields. The highest biodiesel yield obtained was 98% at 1:6
oil-to-methanol molar ratio for both 1 wt% and 1.5 wt% potassium hydroxide (KOH) at a reduced
reaction time (30 seconds). The chemical composition of FAME (biodiesel) obtained from different
conditions
i
contained palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) and 70% linoleic acid
(C18:2). The physical properties (cetane number, viscosity, density and FAME content) of biodiesel
produced met the SANS 1935 specification. The energy consumption was reduced from 1.2 kWh with the
traditional transesterification to
0.0067 kWh with the microwave transesterification.
Microwave irradiation was shown to be effective in significantly lowering the energy consumption
for production of biodiesel with good quality for small scale producers. / Thesis (MSc (Engineering Sciences in Chemical Engineering))--North-West University, Potchefstroom Campus, 2013
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Jaunųjų krepšininkų 12–13 metų fizinių krūvių intensyvumo ypatumai / Peculiarities in intensity of physical loads of 12-13 years old boys basketball playersBaltrušaitis, Arvydas 18 June 2014 (has links)
Tyrimo aktualumas. Objektyvus ir informatyvus fizinio krūvio intensyvumo rodiklis yra širdies
susitraukimo dažnis per minutę (Velenksy et al., 1987; Velensky, 1999; Buceta, 2000; Papadopoulos et
al., 2002; Balčiūnas & Stonkus, 2003; Filho et al., 2003; McKeag, 2003;Petridis et al., 2004; Matthew
& Delextrat, 2009; Ziv & Lidor, 2009; Abdelkrim et al., 2010; Castagna et. al., 2011), kuris įvertina
fizinės veiklos intensyvumą bei gali būti matuojamas dažnai ir esamu laiku (Westerterp, 2009).
Daugelio mokslininkų (Beam, Merrill, 1994; Rodriquez & Alonso et al., 2003) plačiai tyrinėjama, kaip
krepšininkai reaguoja į fizinius krūvius, tačiau pasigendama tyrimų apie jaunųjų krepšininkų (12–16
metų) fizinių krūvių intensyvumo rodiklius per rungtynes ir pratybas.
Tyrimo problema: siekiant jaunųjų krepšininkų (12–13 metų) tinkamo sportinio parengtumo, būtina
taikyti fizinius krūvius, adekvačius rungtyniavimo fizinių krūvių intensyvumui.
Hipotezė: per krepšinio pratybas fizinių krūvių intensyvumas yra adekvatus rungtyniavimo
intensyvumui.
Tikslas: nustatyti jaunųjų krepšininkų (12–13 metų) rungtyniavimo ir treniravimo fizinių krūvių
intensyvumo ypatumus.
Uždaviniai:
1. Nustatyti ir įvertinti jaunųjų krepšininkų 12–13 metų vyraujančių fizinių krūvių per rungtynes ir
pratybas ir intensyvumą.
2. Nustatyti žaidėjų biologinės krūvio vertės įvertinimo per rungtynes ir pratybas ypatumus.
Išvados:
1. Fizinių krūvių intensyvumas, modeliuotų ir įprastinių pratybų metu vyravo vidutinio, didelio... [toliau žr. visą tekstą] / Importance of the research. Heart rate per minute is objective and informative index of physical
intensity (Velenksy et al., 1987; Velensky, 1999; Buceta, 2000; Papadopoulos et al., 2002; Balčiūnas &
Stonkus, 2003; Filho et al., 2003; McKeag, 2003;Petridis et al., 2004; Matthew & Delextrat, 2009; Ziv
& Lidor, 2009; Abdelkrim et al., 2010; Castagna et. al., 2011). Heart rate evaluates the intensity and
can be measured frequently and at present (Westerterp, 2009). Basketballers' physical load, reaction to
the load are being analysed on frequent basis however there are not many basketball game researches
on the boys between 12 and 16 years (Beam & Merrill, 1994; Rodriquez & Alonso et al., 2003).
Research hypothesis: physical load intensity of specific basketball training is adequate to the intensity
of training.
Research problem: in order to achieve the physical fitness of junior basketball players, it is vital to
apply physical loads which are adequate to the intensity of the physical loads in the game.
Research object: intensity of junior basketball players‘ physical loads.
Research aim is to estimate the peculiarities of physical loads intensity of junior basketball players (of
12-13 years old) during the training and in the game.
Research objectives:
1. to estimate the dominant loads in the game and training of junior basketball players.
2. to estimate peculiarities of players‘ biological load values during training and in the game.
Conclusion:
1. Intensity of physical loads... [to full text]
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Article: Reducing the electricity cost of a three-pipe water pumping system : a case study using software / White RautenbachRautenbach, John White January 2004 (has links)
Efficient control is often the most cost-effective option to improve on the running cost
of a Three-Pipe Water Pumping System. However, the effect of changing the control
strategy (i.e. on energy consumption) is usually difficult to predict. To obtain this
information more easily, a new simulation tool, QUICKcontrol, was developed. This
new tool was used to investigate the energy cost savings potential in a Three-Pipe
Water Pumping System. The influence of pump scheduling, dam level set points,
control parameters and different combinations thereof was investigated. The
simulation models were firstly verified with measurements obtained from the existing
system to confirm their accuracy for realistic control retrofit simulations. With the aid
of the integrated simulation tool it was possible to predict savings of R 195'000 per year with an average 3.8 MW of load shifted. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.
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A new approach to ensure successful implementation and sustainable DSM in RSA mines / Daniël Francois le RouxLe Roux, Daniël Francois January 2005 (has links)
In this study a new tool was developed that made new approaches possible for the successful
implementation of Demand Side Management (DSM) projects. The new approaches are
incorporated into a generic tool that makes it possible for Energy Services Companies (ESCos) to undertake DSM projects that were previously not possible with currently available technology.
Through these new approaches, maximum results can be obtained on a sustainable basis on the
clear water pumping systems of South African mines.
The author was responsible and participated in four different investigations and implementations of
DSM projects. These were grouped into three case studies. Each of these studies required different
new innovations.
The innovations described in this thesis include the adaptation of the Real-time Energy
Management System (REMS) that was developed and marketed by HVAC International, to mines
with intricate pumping systems, mines without any instrumentation and control infrastructure, as
well as to mines that make use of a Three Pipe Water Pumping System.
The tool developed and applied in these projects was part of Eskom's DSM programme. In this
programme, large electricity clients who wish to shift electrical load out of peak periods, are
assisted by having the total costs of such projects funded by Eskom. The fact that the clients will
most likely enjoy substantial electricity cost savings, (by not having to pay the high peak prices), is
a major attraction of this programme. Nevertheless, the programme is not moving as fast as it
should.
The National Energy Regulator (NER) has set an annual target of 153 MW load to be shifted since
2003. By the end of 2005, the accumulated target load to be shifted will be 459 MW. However,
Eskom has indicated that an accumulated total of only 181 MW load will have been shifted by the
end of 2005. This means that the Eskom DSM programme has actually only achieved 39% of its
target.
The innovations described in this thesis will help ESCos to address this shortfall more effectively / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006
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Researching the long-term impact of load management projects on South African mines / Nicolaas Cornelius Jacobus Marthinus de KockDe Kock, Nicolaas Cornelius Jacobus Marthinus January 2006 (has links)
Eskom is currently facing an energy crisis due to the limited operational electricity generating
capacity in South Africa. The historically low electricity price, the rapid growth in economy
and the energy intensive nature of South African industries are the most common reasons for
the peak supply problem.
Various supply and demand technologies have been identified to address this energy crisis.
Due to the lengthy process of building new peaking load power stations, Eskom has initiated
the Demand-side Management (DSM) programme as a solution to the short-term supply
problem.
The National Energy Regulator (NER) has set targets to Eskom DSM to reduce the evening
peak demand by 153 MW per annum and 4 255 MW over a 20-year planning horizon. Due to
the energy intensive nature of the mining industry, it has been targeted for DSM savings. To
date there have been a number of DSM projects implemented on the clear-water pumping
systems of various mines, with a large potential for DSM savings identified on future projects
still unrealised.
The generation benefit of DSM load-shifting projects is twofold; firstly Eskom's evening load
capacity increases due to the reduction in demand during these periods and secondly, the
mine receives electricity cost savings due to load management practices. Because Eskom
DSM is dependent on the client consumer to accept and roll-out the DSM programme, client
satisfaction is of paramount importance. Due to the fact that load-shifting efforts require from
the mine to change their normal operating schedules, there is uncertainty on the impact and
knock-on effects of DSM projects on a mine.
Therefore, the purpose of this study is to investigate and thereafter quantify the overall
impact of DSM load-shifting on the clear-water pumping system of South African mines. A
generic model was developed by performing case studies on existing DSM projects. This
model was then applied to future DSM projects to validate the findings made throughout the
research study.
The case studies performed on existing DSM projects, as well as the results obtained when
modelling the overall impact of DSM on future mines, proofs that DSM definitely benefits a
mine. The total annual cost saving on the four future DSM projects is predicted to be in the
order of R 7.64 million instead of the R 4.27 million when considering only the electricity cost
savings to the mine. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.
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Comparison between automated and manual DSM pumping projects / R.P. RichterRichter, Rudolph Petrus January 2008 (has links)
The purpose of this dissertation is to identify the best alternative method of load shifting on clear water pumping systems in the mining industry. This can be done through a comparison analysis between manual and automated Demand Side Management (DSM) projects. The study holds benefits for Eskom and any client wishing to participate in the program. Eskom, by choosing the best method, will ensure sustainable load shifting while the client benefits financially through lower electricity costs.
In order to perform this study, research was conducted on the requirements for additional electricity supply in South Africa. Research showed that there is an urgent requirement for additional electricity supply to ensure continued economical growth. DSM was identified as one of the most favourable methods that could be implemented to address the problem. A reason for this is DSM projects are economically viable and can be implemented in a relatively short time. The initiative would also decrease the need for increasing electrical generation capacity.
During the research study important information regarding the computation process for load shifting and cost saving performance was gathered. Research was also conducted on the effect of DSM on labour and maintenance cost reduction, as well as economical engineering methods that can be used for alternative selection. The difference in performance between automated and manual systems was compared. The
results showed that a 40% improvement of automated systems over manual systems were attainable and sustainable. This will realise a total saving of approximately 45% in electricity costs for the client. Savings in labour and maintenance costs are shown to be achievable through the automation of pumping systems. These saving results were used in the Engineering Economic alternative selection methods where applicable. Economic calculations confirmed that automated projects are the most viable control method.
From the comparison study, it is shown that automated controlled systems are more
advantageous than manually controlled systems. It will therefore be in the best interest of the client to automate a manually controlled pumping system, as it will result in additional load shifting and cost saving. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.
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