When mixing and mastering modern music, many engineers strive for making the end product to be perceived as loud as possible without sacrificing audio quality. Achieving this will often involve reducing the dynamic range of a track through peak limiting. By reducing the level of the loudest transients, the additional headroom can be used to raise the overall level of the track. This method of maximizing loudness through transient suppression has, arguably, made it more relevant to understand the human perception of transients. By further understanding the psychoacoustical factors that plays a role in how transient loudness is perceived, engineers could hopefully achieve greater audio quality while maximizing loudness, if desirable. This paper will focus on how the signal duration of a transient will affect its perceived loudness and potentially compensate for level changes within transients. The fact that sound signals of longer duration are perceived as louder than signals of shorter duration has been proven several times in prior research. This effect is tested again, in this research, by letting participants match the loudness of several short pink noise bursts of varying durations. The noise bursts are designed to mimic the envelope of a typical snare drum transient, which makes the stimuli differ from stimuli tested in prior experiments testing the same effect. Based on the result from this experiment, each transient is normalized to be perceived as equally loud. Then, a stationary component is added to every transient to make each stimuli mimic a full typical snare drum. In a second experiment, each stimuli is then compared against each other in an ABX test to see if listeners can perceive the differences.   The results from the first experiment showed that transients were perceived to be approximately 0.3 dB louder per 5 ms increase in duration. In the second experiment, listeners failed to hear the differences between stimuli when transient duration differed less than 5 ms. For differences in duration longer than this, listeners correctly identified the differences.

In recent years, with the continuous growth of population, people's demand for housing is also increasing. Especially since the 21st century, the number of high-rise apartments in major cities in the world has increased significantly. As the mainstream technology in high-rise buildings,the formwork method is developing and many new formwork systems are appeared. In a complete construction project, although the cost of formwork is not high, it also requires a lot of manpower and time limit. That is why it is very important to choose the appropriate formwork. They have their unique advantages and disadvantages, whether it is the traditional wooden formwork, the current mainstream beam formwork and frame formwork, or the new aluminum system formwork. Therefore, with the continuous innovation of formwork technology, that the application of formwork in high-rise buildings should also develop in a diversified direction. This article will conduct an economic and technical analysis of various common formworks to discuss how to choose high-rise building formworks and analyze the rationality of the selection, that combined with actual projects in China. The importance of the formwork mothod in the economic execution of concrete structures is summarized through the comparison between the various formworks.:1 Introduction 1.1 Importance of formwork in construction 1.2 Overview of formwork engineering development 2 Types of formworks 2.1 Traditional wooden formwork systems 2.2 Modern formwork systems 2.2.1 Girder formwork 2.2.2 Frame formwork 2.3 System formwork 2.3.1 MIVAN Technology 2.4 Comparison of three types of formwork 3 The method of the formwork selection in the construction business 3.1 Selection working method 3.2 Factors influencing the selection of formwork system 4 Cost of formwork 4.1 The cost comparison of traditional formwork and modern formwork 4.2 The Cost comparison of three formworks in one project 4.3 Indirect economic effects of different formworks 4.4 Conclusion 5 Process comparison 5.1 Comparing technology (traditional formwork and MI -VAN formwork) 5.2 Comparison technology (traditional formwork and modern formwork) 5.3 Comparison of the process in two projects 5.3.1 The traditional wooden formwork system used in the Zhang-gong middle School (Jiangxi, China) 5.3.2 Aluminium Formwork system used in the Shenton Way 5.4 Comparing the construction period of the MIVAN formwork and the conventional formwork 5.5 Conclusion 6 Practical examples and evaluation 6.1 The Festival Walk - traditional manual-type wooden formwork 6.2 Belcher's Gardens Redevelopment - traditional manual -type wood form 6.3 Park Avenue (Phase II) - aluminum form 6.4 Conclusion 7 Summary and outlook 7.1 Summary 7.2 Outlook 8 Literature

Experiments on the effects of drugs on behavior maintained by temporal-discrimination procedures have led to discrepant results. Recent experiments suggest that the effects of drugs may differ depending on whether the subject is timing some aspect of its own behavior or some other stimulus. The present experiment used a multiple-schedule procedure composed of a subject-produced and experimenter-imposed component. In the subject-produced component, pigeons categorized the duration of their most recently emitted interresponse time. In the experimenter-imposed component, pigeons categorized the duration of a key light. Morphine generally produced underestimation of time during the subject-produced component, a result in agreement with other recent experiments. Morphine had no systematic effects on accuracy during the experimenter-imposed component. These results are discussed in terms of procedural interactions and a morphine-induced disruption of stimulus control.

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In the past, when deciding the asset allocation, fund managers only concerned the factors of assets. This incomplete way may let pension funds not cover their liabilities. To solve this problem we integrate the factors which influence fund¡¦s assets and liabilities and focus on surplus, which means assets minus liabilities. We use Surplus Optimization Model and Immunization Theory to construct our Liability Driven Investment and Dual Duration Matching Model. We decompose duration to real interest rate duration and inflation rate duration to control the sources of interest rate. Through this method, we can enhance the efficiency of asset allocation to ensure paying pension annuity punctually and avoid the risk of interest rate. Our sample period is Sept. 2001 to Aug. 2005 and sampling frequency is monthly. We use the common investment tools, stocks index, government bond index, 5 years corporate bonds, 3 years bank deposit, 30 days commercial papers, to be the assets we can allocate. We discover that when using liability driven investment and duration matching the longer years we consider the longer assets duration we need. Because government bond index¡¦s duration is shorter than stocks index¡¦s. When we consider longer years the weight of government bond index will decrease and the weight of stocks index will increase. When considered years are 50, the weight of government bond index is 54.74% and the weight of stocks index is 45.26%. The ratio of equity assets to fixed income assets is 84.51% that is similar with pension fund¡¦s ratio, 86.13%. No matter how many years we consider, the weight of bonds is high. But in pension funds¡¦ target allocation the weight of bonds is only 16% and the weights of bank deposit and T-bills are 31%. To take immunization strategy and improve the long term revenue, a large proportion should be allocated from bank deposit and T-bills to bonds.

Thesis (M.Sc. (Statistics)) -- University of Limpopo, 2020 / Several studies indicated a growing trend in terms of frequency and severity of extreme events. Extreme rainfall could cause disasters that lead to loss of property and life. The aim of the study was to model the monthly rainfall variability in selected provinces of South Africa using extreme value distributions. This study investigated the best-fit probability distributions in the five provinces of South Africa. Five probability distributions: gamma, Gumbel, log-normal, Pareto and Weibull, were fitted and the best was selected from the five distributions for each province. Parameters of these distributions were estimated by the method of maximum likelihood estimators. Based on the Akaike information criteria (AIC) and Bayesian information criteria (BIC), the Weibull distribution was found to be the best-fit probability distribution for Eastern Cape, KwaZulu-Natal, Limpopo and Mpumalanga, while in Gauteng the best-fit probability distribution was found to be the gamma distribution. Monthly rainfall trends detected using the Mann–Kendall test revealed significant monotonic decreasing long-term trend for Eastern Cape, Gauteng and KwaZulu-Natal, and insignificant monotonic decreasing longterm trends for Limpopo and Mpumalanga. Non-stationary generalised extreme value distribution (GEVD) and non-stationary generalized Pareto distribution (GPD) were applied to model monthly rainfall data. The deviance statistic and likelihood ratio test (LRT) were used to select the most appropriate model. Model fitting supported stationary GEVD model for Eastern Cape, Gauteng and KwaZulu-Natal. On the other hand, model fitting supported non-stationary GEVD models for maximum monthly rainfall with nonlinear quadratic trend in the location parameter and a linear trend in the scale parameter for Limpopo, while in Mpumalanga the non-stationary GEVD model, which has a nonlinear quadratic trend in the scale parameter and no variation in the location parameter fitted well to the maximum monthly rainfall data. Results from the non-stationary GPD models showed that inclusion of the time covariate in our models was not significant for Eastern Cape, hence the bestfit model was the stationary GPD model. Furthermore, the non-stationary GPD model with a linear trend in the scale parameter provided the best-fit for KwaZulu-Natal and Mpumalanga, while in Gauteng and Limpopo the nonstationary GPD model with a nonlinear quadratic trend in the scale parameter fitted well to the monthly rainfall data. Lastly, GPD with time-varying thresholds was applied to model monthly rainfall excesses, where a penalised regression cubic smoothing spline was used as a time-varying threshold and the GPD model was fitted to cluster maxima. The estimate of the shape parameter showed that the Weibull family of distributions is appropriate in modelling the upper tail of the distribution for Limpopo and Mpumalanga, while for Eastern Cape, Gauteng and KwaZulu-Natal, the exponential family of distributions was found to be appropriate in modelling the upper tail of the distribution. The dissertation contributes positively to the body of knowledge in extreme value theory application to rainfall data and makes recommendations to the government agencies on the long-term rainfall variability and their negative impact on the economy.

Thesis (M. Sc. (Statistics)) -- University of Limpopo, 2020 / The main purpose of modelling rare events such as heavy rainfall, heat waves, wind speed, interest rate and many other rare events is to try and mitigate the risk that might arise from these events. Heavy rainfall and floods are still troubling many countries. Almost every incident of heavy rainfall or floods might result in loss of lives, damages to infrastructure and roads, and also financial losses. In this dissertation, the interest was in modelling average monthly rainfall for South Africa using extreme value theory (EVT). EVT is made up mainly of two approaches: the block maxima and peaks-over thresh old (POT). This leads to the generalised extreme value and the generalised Pareto distributions, respectively. The unknown parameters of these distri butions were estimated using the method of maximum likelihood estimators in this dissertation. According to goodness-of-fit test, the distribution in the Weibull domain of attraction, Gumbel domain and generalised Pareto distri butions were appropriate distributions to model the average monthly rainfall for South Africa. When modelling using the POT approach, the point process model suggested that some areas within South Africa might experience high rainfall in the coming years, whereas the GPD model suggested otherwise. The block maxima approach using the GEVD and GEVD for r-largest order statistics also revealed similar findings to that of the GPD. The study recommend that for future research on average monthly rainfall for South Africa the findings might be improved if we can invite the Bayesian approach and multivariate extremes. Furthermore, on the POT approach, time-varying covariates and thresholds are also recommended. / National Research Foundation (NRF) and South African Weather Service (SAWS)

Knowledge of construction duration is pertinent to a number of project planning functions prior to detailed design development. Funding, financing, and resource allocation decisions take place early in project design development and are significantly influenced by the construction duration. Currently, there is not an understanding of the project factors having a statistically significant relationship with highway construction duration. Other industry sectors have successfully used statistical regression analysis to identify and model the project parameters related to construction duration. While the need is seen for such work in highway construction, there are very few studies which attempt to identify duration-influential parameters and their relationship with the highway construction duration. This research identifies the project factors, known early in design development, which influence highway construction duration. The factors identified are specific to their respective project types and are those factors which demonstrate a statistically-significant relationship with construction duration. This work also quantifies the relationship between the duration-influential factors and highway construction duration. The quantity, magnitude, and sign of the factor coefficient yields evidence regarding the importance of the project factor to highway construction duration. Finally, the research incorporates the duration-influential project factors and their relationship with highway construction duration into mathematical models which assist in the prediction of construction duration. Full and condensed models are presented for Full-Depth Section and Highway Improvement project types. This research uses statistical regression analysis to identify, quantify, and model these early-known, duration-influential project factors. The results of this research contribute to the body of knowledge of the sponsoring organization (Virginia Department of Transportation), the highway construction industry, and the general construction industry at large. / Ph. D.

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