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Fixering av Cross-beam på Fixed Caliper 22"Ohlsson, Johan January 2009 (has links)
Denna rapport behandlar mitt examensarbete som genomfördes i samarbete med Haldex Brake AB. Haldex Brake AB håller på och utvecklare en ny generation broms åt lastbilar. Uppdraget bestod av tre delar. Att ta fram lösningsförslag som säkerhetsställer beläggjärnets placering i förhållande ett beläggjärn så kallad Cross-beam. Att säkerställa att bultar monteras med rätt åtdragningsmoment på 230Nm. Den sista tredjedelen av arbetet bestod i att presentera lösningar som helt eller delvis eliminerar oljud, när olika komponenter med spel, slår i delar i okhuset. I projektet har flera olika principkonstruktioner tagits fram och genom Freddy Olsson utvärderingsmallar har sedan en primärkonstruktion utarbetats fram. I dem andra två resterande projektdelarna belyses lösningarna väldigt generellt av den anledningen att det kräver specialkomponenter.
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Understanding Suicide : A Socio-Economic ApproachJasmin, Jusufbegovic, Johan, Ottoson January 2011 (has links)
This thesis uses a panel of Swedish counties over the years 1976-2007 to investigate the relationship between suicide and a range of socio-economic determinants. Moreover, the thesis is combining sociology and economics in order to understand the part of suicide that can be considered as rational. In addition, suicide is studied separately for total, male and female suicide rates. Contrary to prior research in the field of suicide, this study formally tests for gender differences. Applying a fixed effect model, we managed to uncover a statistically significant gender difference for female labor force participation relation to suicide. When applying fixed effect models most of our results were in accordance with the socio-economic theory of suicide. We found a significant u-shaped relationship between suicide and the level of alcohol sales (consumption). We also found a statistically significant positive relationship between the total suicide rate and female labor force participation. Moreover, we found that higher population density significantly leads to fewer suicides in the total and male model. Furthermore, we found that unemployment increases the male suicide rate. In some cases, however our results contradicted the theory. Our results give evidence that divorce has a negative and significant effect on total and male suicide rate. These findings are not only violating the theoretical framework but previous research as well. We can thus conclude that the socio-economic theory of suicide, in most cases, assistances us to understand suicide.
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Reeb Spaces and the Robustness of PreimagesPatel, Amit January 2010 (has links)
<p>We study how the preimages of a mapping f : X &rarr Y between manifolds vary under perturbations. First, we consider the preimage of a single point and track the history of its connected component as this point varies in Y. This information is compactly represented in a structure that is the generalization of the Reeb graph we call the Reeb space. We study its local and global properties and provide an algorithm for its construction. Using homology, we then consider higher dimensional connectivity of the preimage. We develop a theory quantifying the stability of each homology class under perturbations of the mapping f . This number called robustness is given to each homology class in the preimage. The robustness of a class is the magnitude of the perturbation necessary to remove it from the preimage. The generality of this theory allows for many applications. We apply this theory to quantify the stability of contours, fixed points, periodic orbits, and more.</p> / Dissertation
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Iterative Methods for Common Fixed Points of Nonexpansive Mappings in Hilbert spacesLai, Pei-lin 16 May 2011 (has links)
The aim of this work is to propose viscosity-like methods for finding a specific common fixed point of a finite family T={ T_{i} }_{i=1}^{N} of nonexpansive self-mappings of a closed convex subset C of a Hilbert space H.We propose two schemes: one implicit and the other explicit.The implicit scheme determines a set {x_{t} : 0 < t < 1} through
the fixed point equation x_{t}= tf (x_{t} ) + (1− t)Tx_{t}, where f : C¡÷C is a contraction.The explicit scheme is the discretization of the implicit scheme and de defines a sequence {x_{n} } by the recursion x_{n+1}=£\\_{n}f(x_{n}) +(1−£\\_{n})Tx_{n} for n ≥ 0, where {£\\_{n} }⊂ (0,1) It has been shown in the literature that both implicit and explicit schemes converge in
norm to a fixed point of T (with additional conditions imposed on the sequence {£\ _{n} } in the explicit scheme).We will extend both schemes to the case of a finite family of nonexpansive mappings. Our proposed schemes converge in norm to a common fixed point of the family which in addition solves a variational inequality.
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Fixed-time insemination of porcine luteinizing hormone-treated superovulated beef cows and the resynchronization of beef cows for fixed-time embryo transferNelson, John Stephen 15 May 2009 (has links)
Two trials were conducted to compare the effectiveness of fixed-time artificial
insemination (AI) to AI based upon visual detection of estrus following superstimulation
of donor beef cows. In Trial 1, multiparous beef cows (n = 31) were randomly allotted to
one of three treatments following superstimulation and removal of an intravaginal
progesterone insert (CIDR). Cows in the Control group were inseminated at 12 and 24 h
after onset of estrus. Cows in the Estradiol group were injected with estradiol-17β (1 mg,
im) at 12 h and inseminated at 24 and 36 h after CIDR removal. Cows in the pLH36
group were injected with porcine LH (Lutropin, 12.5 mg, im) at 24 h and inseminated at
36 and 48 h after CIDR removal. Mean numbers of viable embryos were 7.8, 3.6 and
9.6 for Control, Estradiol and pLH36 treatment groups, respectively (P > 0.10). In Trial
2, multiparous beef cows (n = 22) were randomly allotted to one of three treatments
following superstimulation and removal of a CIDR. Sixteen of the cows were
superstimulated a second time approximately 50 days later and allotted to one of the two
treatments that differed from the initial treatment group. Cows in the Control group were
inseminated at 12 and 24 h after onset of estrus. Cows in the two pLH groups were injected with porcine LH (Lutropin,12.5 mg, im) at 24 h after CIDR removal and were
inseminated with either one unit of semen at 36 and 48 h (pLH36) or with two units of
semen at 48 h (pLH48) after CIDR removal. Mean numbers of viable embryos were 3.0,
6.4 and 3.8 for Control, pLH36 and pLH48 treatment groups, respectively (P > 0.10).
These data indicate that administration of pLH can facilitate use of fixed-time AI in
superovulated beef cows without sacrificing embryo production.
The second study evaluated the efficacy of resynchronizing beef cow recipients
using CIDR devices for only 7 or 14 d. Recipient cows received CIDRs either on the
day of transfer (n = 88) or 7 d post-transfer (n = 230). All CIDRs were removed on d 21
and cows were observed for estrus between d 22 and 24. Cows that displayed estrus
were ultrasounded on d 30, those cows not pregnant that possessed a CL had an embryo
transferred that day. Cows were later examined for pregnancies approximately 23 to 30
d later. There were no differences in pregnancy rates between cows with 7 or 14 d
CIDRs and therefore data were combined. Pregnancy rates at two different ranches
indicate that beef cow recipients can be successfully resynchronized by insertion of a
CIDR without compromising pregnancy rates of transferred embryos. At Center Ranch
the pregnancy rate for the first transfer was 57% while the resynchronized group that
received the second transfer had a pregnancy rate of 55%. At Mound Creek Ranch the
first transfer of embryos produced 59% pregnancy rates while the second transfer had a
pregnancy rate of 71%. No significant differences (P > 0.05) were observed between the
pregnancy rates of the initial transfer and those of the resynchronized transfer using only CIDRs, indicating that resynchronization using CIDRs can be used without reducing
pregnancy rates.
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Fixed Bed Countercurrent Low Temperature Gasification of Dairy Biomass and Coal-Dairy Biomass Blends Using Air-Steam as OxidizerGordillo Ariza, Gerardo 2009 August 1900 (has links)
Concentrated animal feeding operations such as cattle feedlots and dairies
produce a large amount of manure, cattle biomass (CB), which may lead to land, water,
and air pollution if waste handling systems and storage and treatment structures are not
properly managed. However, the concentrated production of low quality CB at these
feeding operations serves as a good feedstock for in situ gasification for syngas (CO and
H2) production and subsequent use in power generation. A small scale (10 kW)
countercurrent fixed bed gasifier was rebuilt to perform gasification studies under quasisteady
state conditions using dairy biomass (DB) as feedstock and various air-steam
mixtures as oxidizing sources. A DB-ash (from DB) blend and a DB-Wyoming coal
blend were also studied for comparison purposes. In addition, chlorinated char was also
produced via pure pyrolysis of DB using N2 and N2-steam gas mixtures.
The chlorinated char is useful for enhanced capture of Hg in ESP of coal fired
boilers. Two main parameters were investigated in the gasification studies with air-steam
mixtures. One was the equivalence ratio ER (the ratio of stochiometric air to actual air) and the second was the steam to fuel ratio (S:F). Prior to the experimental studies, atom
conservation with i) limited product species and ii) equilibrium modeling studies with a
large number of product species were performed on the gasification of DB to determine
suitable range of operating conditions (ER and S:F ratio). Results on bed temperature
profile, gas composition (CO, CO2, H2, CH4, C2H6, and N2), gross heating value (HHV),
and energy conversion efficiency (ECE) are presented.
Both modeling and experimental results show that gasification under increased
ER and S:F ratios tend to produce rich mixtures in H2 and CO2 but poor in CO.
Increased ER produces gases with higher HHV but decreases the ECE due to higher tar
and char production. Gasification of DB under the operating conditions 1.59<ER less than6.36
and 0.35<s:f>less than0.8 yielded gas mixtures with compositions as given below: CO (4.77 -
11.73 %), H2 (13.48 - 25.45%), CO2 (11-25.2%), CH4 (0.43-1.73 %), and C2H6 (0.2-
0.69%). In general, the bed temperature profiles had peaks that ranged between 519 and
1032 degrees C for DB gasification.
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Measure-Driven Algorithm Design and Analysis: A New Approach for Solving NP-hard ProblemsLiu, Yang 2009 August 1900 (has links)
NP-hard problems have numerous applications in various fields such as networks,
computer systems, circuit design, etc. However, no efficient algorithms have
been found for NP-hard problems. It has been commonly believed that no efficient algorithms
for NP-hard problems exist, i.e., that P6=NP. Recently, it has been observed
that there are parameters much smaller than input sizes in many instances of NP-hard
problems in the real world. In the last twenty years, researchers have been interested
in developing efficient algorithms, i.e., fixed-parameter tractable algorithms, for those
instances with small parameters. Fixed-parameter tractable algorithms can practically
find exact solutions to problem instances with small parameters, though those
problems are considered intractable in traditional computational theory.
In this dissertation, we propose a new approach of algorithm design and analysis:
discovering better measures for problems. In particular we use two measures instead of
the traditional single measure?input size to design algorithms and analyze their time
complexity. For several classical NP-hard problems, we present improved algorithms
designed and analyzed with this new approach,
First we show that the new approach is extremely powerful for designing fixedparameter
tractable algorithms by presenting improved fixed-parameter tractable algorithms
for the 3D-matching and 3D-packing problems, the multiway cut problem, the feedback vertex set problems on both directed and undirected
graph and the max-leaf problems on both directed and undirected graphs. Most of
our algorithms are practical for problem instances with small parameters.
Moreover, we show that this new approach is also good for designing exact algorithms
(with no parameters) for NP-hard problems by presenting an improved exact
algorithm for the well-known satisfiability problem.
Our results demonstrate the power of this new approach to algorithm design and
analysis for NP-hard problems. In the end, we discuss possible future directions on
this new approach and other approaches to algorithm design and analysis.
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Design of Controllers for a Multiple Input Multiple Output SystemHarris, Amanda Lynne 2012 May 1900 (has links)
A method of controller design for multiple input multiple output (MIMO) system is needed that will not give the high order controllers of modern control theory but will be more systematic than the “ad hoc” method. The objective of this method of design for multiple input multiple output systems is to find a controller of fixed order with performance specifications taken into consideration. An inner approximation of the stabilizing set is found through the algorithm discussed in Keel and Bhattacharyya’s "Fixed order multivariable controller synthesis: A new algorithm." The set satisfying the performance is then approximated through one of two algorithms; a hybrid of two optimization algorithms or the grid algorithm found in Lampton’s "Reinforcement Learning of a Morphing Airfoil-Policy and Discrete Learning Analysis." The method is then applied to five models of four aircraft; Commander 700, X-29, X-38, and F-5A using controllers of first and second orders.
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MP3 Decoding Software Implementation for a DSP-enhanced MicrocontrollerChen, Shi-Wei 09 January 2004 (has links)
Multimedia workloads have always held an important role in embedded applications. Products are multifarious, such as various modeling mobile phone, MP3 player which is deft and convenient to carry and PDA which is popular with workers. We touch them all the time in our life. So these kinds of products are usually not high price. If their design cost and production cost are lower than others, then they can earn profits in this competition market. In so much multimedia applications, the most popular MP3 is our research goal.
The design methods of multimedia audio application are using high performance CPU or combining general purpose processor with a DSP. Their performance satisfied the demand of multimedia application really, but the system hardware cost will increase at the same time. It is not the best solution in embedded products which emphasizing that low cost is better than high performance.
So, my thesis will focus on MP3 algorithm optimization. We analyzed MP3 decoder algorithms, and found out the key operation. Using the SIMD operation feature of low cost multimedia processor development from our lab (It¡¦s named ME-MCU) to accelerate the processor speed. Then, I don¡¦t need a strong CPU or DSP, and I also can complete the MP3 decode operations as well. When I optimized the MP3 algorithm, I hope to provide some suggestion for ME-MCU modification. And the multimedia application will more agree with ME-MCU.
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Political economy analysis of fixed network industry in TaiwanSu, In-hao 21 June 2004 (has links)
This essay mainly utilize theoretical tool of ¡§State Centralism¡¨ to observe fixed network industry development history in Taiwan. After 1980s, based on characteristics of fixed network, state monopolizes the industry. However, digital techniques develop rapidly from last 1970s, the legitimacy of traditionally state monopoly model is gradually decrease. In the meantime, authoritatrian regime reform and economic liberalization in Taiwan start from 1980s to make state autonomy decreasing and launch liberalization of fixed network industry.
Nevertheless, state role in industry didn¡¦t disappear after fixed network liberalization. In this research, author point out fixed network liberalization process in Taiwan is one kind of state centralism model. The liberalization is an ¡§instrument¡¨ but ¡§object¡¨ for state to accelerate development of information society and industrial structure reform in Taiwan.
After fixed network market open in 2000, the market almost still monopolized by Chunghwa Telecom Co. It never achieves ¡§competitive development¡¨ environment planed by state. For fixed network industry of Taiwan, though state have outline regulatory policy, how to achieve a competitive environment after liberalization is the most important challenge to state to face new age of digital convergence.
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