No description available.

CAI combustion and the factors affecting it were intensively investigated in a single cylinder, air-assisted gasoline direct injection engine. CAI was achieved by means of residual gas trapping by utilising low-lift short duration camshafts and early closing of the exhaust valves. The effects of EVC (Exhaust Valve Closure) and IVO (Inlet Valve opening) timings, spark timing, single and split injection timings, coolant temperature, compression ratio, cam lift and duration on exhaust emissions and CAI operation were investigated experimentally. Engine speed throughout the course of the experiments, was varied from 1200rpm to 2400rpm and the air/fuel ratio was altered from stoichiometric to the misfire limit. The results show that the EVC timing, compression ratio, cam lift and duration had significant influences on CAI combustion and emissions. Early EVC when combined with higher compression ratio and higher cam lift, enhance CAI combustion operation and stability. IVO timing had minor effect on CAI combustion while spark timing hardly affects CAI operation as soon as fully-developed CAI conditions were established. Coolant temperature was revealed to have substantial impact on CAI combustion when the coolant temperature was below 65C. The results also show the importance of injection timing. Early injection gave faster and more stable combustion, less HC and CO emissions, but more prone to knocking combustion and higher NOx emissions. Furthermore, CAI operation range could considerably be extended with injection during the recompression process. Late injection led to slower and unstable combustion, higher HC and CO emissions but lower combustion noise and NOx emissions. Split injection gave even further extension of CAI range in both stoichiometric and lean mixture operations. All the above clearly suggest, that optimising injection timing and using split injection is an effective way to control and extend CAI operation in a direct injection gasoline engine.

"Previous implementations of digital background calibration for cyclic ADCs have required linear amplifier behavior in the gain stage for accurate correction. Correction is digital decoding of ADC outputs to determine the original ADC input. Permitting nonlinearity in the gain stage of the ADC allows for less demanding amplifier design requirements, reducing power and size. However this requires a method of determining the value of this variable gain during digital correction. Look up tables (LUTs,) are an effective and efficient method of compensating for analog circuit imperfections. The LUT correction and calibration method discussed in this work has been simulated using Cadence integrated circuit simulation ADC specifications and MATLAB."

No description available.

The so-called passive in Māori has been the topic of a long-standing debate in the linguistics literature. Its frequency, especially in past tense narratives, makes this construction an atypical passive. It has been suggested that the passive in Māori is used with perfective (Clark 1973) and dynamic (Bauer 1997) events, and when the clause contains an affected direct object (Chung 1978). This thesis finds that all of these suggestions are correct, but, rather than a passive construction, it is ergative, so that Māori has split-ergativity. As predicted under the Transitivity Hypothesis (Hopper & Thompson 1980), the most transitive clauses in Māori have ergative marking, and less transitive clauses are accusatively marked. Transitivity is understood as a property of an entire clause, involving a number of factors, and the most important features of transitivity in Māori are PARTICIPANTS, AFFECTEDNESS OF O, ASPECT and PUNCTUALITY. Clauses that are low in transitivity are uniformly accusative, in both their morphology and syntax. However, highly transitive clauses, which we expect to follow ergative alignment, have some evidence of syntactic accusativity. This mixed behaviour follows directly from the Inverse Grammatical Relations Hypothesis (Manning 1996). Manning claims syntactic constructions like control, binding and imperative addressee are accusatively aligned in all languages, because they are restricted at argument structure. Languages can only be ergative at the level of grammatical relations, where syntactic processes such as relative clauses, question formation and topicalisation are restricted. It then follows that ergativity is only present in Māori at gr-structure in the most highly transitive clauses. We also look at Māori from a diachronic perspective, and see that it differs from its Eastern Polynesian sisters, which are all accusative. Māori is different because the extension of the imperfective pattern did not spread to all transitive clauses, thus preventing a reanalysis of imperfective clauses as active.

No description available.

Split-mouth trials are a design of randomized controlled trial in dentistry in which divisions of the mouth are the units of randomization. Since there is more than one tooth in each mouth division, the structure of the data is complex, which can create difficulties in the statistical analysis. The aim of this study was to determine what is the most appropriate method to analyze split-mouth trials with continuous outcomes, with regards to the treatment effect estimates, power, type-I error, confidence interval coverage and confidence interval width. A superiority split-mouth trial in the field of periodontology was simulated, using two mouth divisions and varying underlying study characteristics such as correlation among teeth, treatment effects and sample size. Twenty-four statistical methods were compared across 315 scenarios. The performance of the statistical methods depended mainly on the correlation among the data, and a paired t-test performed the best across the different scenarios.

Split-mouth trials are a design of randomized controlled trial in dentistry in which divisions of the mouth are the units of randomization. Since there is more than one tooth in each mouth division, the structure of the data is complex, which can create difficulties in the statistical analysis. The aim of this study was to determine what is the most appropriate method to analyze split-mouth trials with continuous outcomes, with regards to the treatment effect estimates, power, type-I error, confidence interval coverage and confidence interval width. A superiority split-mouth trial in the field of periodontology was simulated, using two mouth divisions and varying underlying study characteristics such as correlation among teeth, treatment effects and sample size. Twenty-four statistical methods were compared across 315 scenarios. The performance of the statistical methods depended mainly on the correlation among the data, and a paired t-test performed the best across the different scenarios.

RODRIGUES, Francisco Caio Maia. Evolução de split grammars para otimização de construções procedurais. 2014. 49 f. Dissertação (Mestrado em Ciência da Computação)-Universidade Federal do Ceará, Fortaleza, 2014. / Submitted by Anderson Silva Pereira (anderson.pereiraaa@gmail.com) on 2017-01-10T18:58:03Z No. of bitstreams: 1 2014_dis_fcmrodrigues.pdf: 6745695 bytes, checksum: 7fd10d5fff50663bf084d4eb5ad0a949 (MD5) / Approved for entry into archive by Rocilda Sales (rocilda@ufc.br) on 2017-01-11T15:39:12Z (GMT) No. of bitstreams: 1 2014_dis_fcmrodrigues.pdf: 6745695 bytes, checksum: 7fd10d5fff50663bf084d4eb5ad0a949 (MD5) / Made available in DSpace on 2017-01-11T15:39:12Z (GMT). No. of bitstreams: 1 2014_dis_fcmrodrigues.pdf: 6745695 bytes, checksum: 7fd10d5fff50663bf084d4eb5ad0a949 (MD5) Previous issue date: 2014 / Procedural modeling has been successfully applied to the automatic building generation problem. Among several techniques to tackle the problem of procedural building generation, the use of Split Grammars has increased, even being deployed in commercial CAAD (Computer-Aided Architectural Design) software. This work proposes a technique to optimize Split Grammars using Genetic Algorithm. The main goal is to automatically create grammars that only generate models with certain desirable characteristics, either from a series of manually written grammars or randomly created ones. The proposed thecnique searches the space of the input grammars’s rules to develop new better grammars, i.e., grammars that generate models with certain predefined feature. The proposed technique was successfully applied, as will be shown, to the maximization of symmetry of building facades, leading to the creation of realistic models. / Modelagem procedural tem sido aplicada com sucesso para resolver o problema da construção automática de ambientes urbanos. Dentre as várias técnicas existentes para a geração procedural de construções utilizando gramáticas, Split Grammars têm especial destaque devido ao seu amplo uso, estando presente até mesmo em softwares comerciais de CAAD (Computer-Aided Architectural Design). Este trabalho propõe uma técnica para otimização de Split Grammars utilizando algoritmos genéticos. O objetivo é gerar, automaticamente, gramáticas capazes de criar modelos que apresentem alguma característica desejada, seja a partir de uma série de gramáticas feitas manualmente por um usuário ou de gramáticas geradas aleatoriamente. O método proposto realiza uma busca no espaço das regras das gramáticas dadas como entrada a fim de criar novos tipos de gramáticas melhores, ou seja, que possuam uma boa estrutura de acordo com algum critério pré-definido pelo usuário. Assim, é demonstrada a eficácia da técnica proposta aplicando-a ao problema de maximização de simetria em fachadas de construções, obtendo modelos realisticamente plausíveis.

A new equivalent circuit of left-handed (LH) microstrip transmission line loaded with Complementary split-ring resonators (CSRRs) is presented. By adding the magnetic coupling into the equivalent circuit, the new equivalent circuit presents a more accurate cutoff frequency than the old one. The group delay of CSRRs applied with microstrip transmission line (TL) is also studied and analyzed into two cases which are passive CSRRs delay line and active CSRRs delay line. In the first case, the CSRRs TL is analyzed. The group delay can be varied and controlled via signal frequency which does not happen in a normal TL. In the active CSRRs delay line, the CSRRs loaded with TL is fixed. The diodes are added to the model between the strip and CSRRs. By observing a specific frequency at 2.03GHz after bias DC voltages from -10V to -20V, the group delay can be moved from 0.6ns to 5.6ns. A novel microstrip filter is presented by embedding CSRRs on the ground plane of microstrip filter. The filter characteristic is changed from a 300MHz narrowband to a 1GHz wideband as well as suppression the occurrence of previous higher spurious frequency at 3.9GHz. Moreover, a high rejection in the lower band and a low insertion loss of <1dB are achieved.Finally, it is shown that CSRRs applied with planar antenna can reduce the antenna size. The structure is formed by etching CSRRs on the ground side of the patch antenna. The meander line part is also added on the antenna patch to tune the operation frequency from 1.8GHz downward to 1.73GHz which can reduce the antenna size to 74% of conventional patch antennas. By using the previous antenna structure without meander line, this proposed antenna can be tuned for selecting the operation frequency, by embedding a diode connected the position between patch and ground. The results provide 350MHz tuning range with 35MHz bandwidth.