Unit roots and multiple structural breaks in real output

Utilizing re-sampling. Methods, we present evidence on the rejection probabilities for difference-stationary and trend-stationary models for Mexico’s real and real per-capita annual gross domestic product. The trend stationary alternative allows for stationary fluctuations around a long-run trend function with endogenously determined multiple structural breaks, via global and sequential search methods. The number of breaks is determined using a unit-root rejection stopping rule and a parameter-constancy stopping rule.

Polydispersity Effects in the Dynamics and Stability of Bubbling Flows

The occurrence of swarms of small bubbles in a variety of industrial systems enhances their performance. However, the effects that size polydispersity may produce on the stability of kinematic waves, the gain factor, mean bubble velocity, kinematic and dynamic wave velocities is, to our knowledge, not yet well established. We found that size polydispersity enhances the stability of a bubble column by a factor of about 23% as a function of frequency and for a particular type of bubble column. In this way our model predicts effects that might be verified experimentally but this, however, remain to be assessed. Our results reinforce the point of view advocated in this work in the sense that a description of a bubble column based on the concept of randomness of a bubble cloud and average properties of the fluid motion, may be a useful approach that has not been exploited in engineering systems.Comment: 11 pages, 2 figures, presented at the 3rd NEXT-SigmaPhi International Conference, 13-18 August, 2005, Kolymbari, Cret

Softly Broken N=2 QCD with Massive Quark Hypermultiplets, I

We present a general analysis of all the possible soft breakings of N=2 supersymmetric QCD, preserving the analytic properties of the Seiberg-Witten solutions for the SU(2) group with Nf=1, 2, 3 hypermultiplets. We obtain all the couplings of the spurion fields in terms of properties of the Seiberg-Witten periods, which we express in terms of elementary elliptic functions by uniformizing the elliptic curves associated to each number of flavors. We analyze in detail the monodromy properties of the softly broken theory, and obtain them by a particular embedding into a pure gauge theory with higher rank group. This allows to write explicit expressions of the effective potential, which are close to the exact answer for moderate values of the supersymmetry breaking parameters. The vacuum structures and phases of the broken theories will be analyzed in the forthcoming second part of this paper.Comment: 35 pages, 3 figures, LaTeX file. Minor corrections in a few formulae, typos correcte

Peningkatan Keterampilan Tajhiz Mayit Melalui Penggunaan Laboratorium Pai Pada Siswa Kelas XI Ipa-1 SMA Negeri 8 Banda Aceh

This research intended to know teachers\u27 activities to manage the learning process of tajhiz mayit by using the PAI laboratory; students\u27 activities in the tajhiz mayit by using the PAI laboratory; and the practical ability of students of class XI IPA-1 SMAN 8 Banda Aceh on tajhiz materials. This research is a Classroom Action Research (CAR) with four cycles, each consists of four stages: planning, implementation, observation, and reflection. The results of data analysis indicated that there wis an increase in the average value of students and their active participation in each subject matter, ranging from bathing, shrouding, doing prayer for, and burying the dead body. For example, teacher activity in managing learning process in the first cycle of first meeting on bathing the dead reached 64.28 in average falling into mild category; and at second meeting increased to 87.71 in average with good category. In the cycle II, on the first meeting on the subject of shrouding the dead body was 64.28 in average falling into mild category; and at the second meeting increased to 89.28 on average falling into a very good category. Likewise, the increase in the score average and students\u27 participations in other cycles after the use of CAR in the laboratory

LA CIENCIA Y LA TECNOLOGÍA EN LA ECONOMÍA

Las primeras evidencias sobre los efectos que tuvo la ciencia y la tecnología en la esfera de la producción y sus implicaciones se presentan débilmente durante el período de la Primera Revolución Industrial (S. XVII y XVIIII) que ”refiere al imperio de las máquinas y el comienzo del sistema fabril”1 y se han profundizado con el paso del tiempo marcando el cambio profundo en la estructura económica, social, política y cultural. Los primeros cambios se presentan a fines de la Edad Media2, los que abren el paso a la Edad Moderna considerada como la fase intermedia hacia el capitalismo y la Contemporánea que se inicia con la industrialización3 hasta nuestros días, de cuyos sucesos, especialmente la teoría económica ha dado interpretaciones sobre las causas que iniciaron e impulsaron estos cambios y sus efectos

Nucleation, Transformation, and Impacts of Atmospheric Aerosols

Atmospheric aerosols are a key contributor to pollution, adversely affect human health, and can alter global climate. Several questions concerning atmospheric aerosols persist, including: ‘Which atmospheric species are integral for aerosol formation in the atmosphere?’, ‘What happens to aerosols after emission into or formation in the atmosphere?’, ‘Does maternal exposure to aerosols during pregnancy fundamentally alter her offspring?’, and ‘Can we utilize gas phase chemistry models to further our understanding of atmospheric aerosols?’. A series of chamber, observational, and computational studies have been conducted to investigate these scientific questions. Globally, new particle formation (NPF) events account for more than 50% of the aerosols in the troposphere, but the chemical species and mechanisms responsible for NPF have yet to be fully understood. To explicate the role of organic compounds in NPF, laboratory experiments have been conducted to investigate aerosol nucleation and growth from the photochemical oxidation of biogenic and anthropogenic volatile organic compounds (VOCs). Here we show that the NPF is dependent on the VOC species and that the global pattern of NPF is likely governed by the available VOCs. A suite of instruments was deployed in Beijing to measure a comprehensive set of aerosol properties in order to elucidate the aerosol formation mechanisms and the evolution of aerosol properties. NPF consistently occurred on clean, windy days, and the high aerosol mass observed during haze events is attributable to the continuous growth from the nucleation-mode particles over multiple days to produce a high concentration of larger particles. Our results reveal that the severe haze in Beijing is likely due to the concentrated aerosol precursor gases and the large-scale meteorological conditions. Model simulations indicate that the persistent high concentrations of NO2 in Beijing and the frequent periods of high aerosol loading leads to elevated HONO levels and sustained oxidizing capacity. To determine the mechanism through which aerosols influence human health, a series of animal exposure studies have been conducted to investigate the transgenerational effects. In each experiment, Sprague-Dawley rats were continuously exposed between days 0 and 18 of gestation to controlled conditions to represent either clean (~5 µg m^-3) or polluted (~150 µg m^-3) environments. The gestation length, litter size, birth weight, and sex ratio were assessed throughout the animal exposure studies. The preliminary results indicate the development of several organs and the birth weight may be influenced by prenatal exposure to pollutants and the degree of response may also be sex dependent

Business platforms: A model for the 21st century a sustainability long-term strategy for a hotel in Mexico

This work is the compilation of 8 weekly class deliverables for Business Platforms - A Model for the 21st Century lectured at Regis University in Colorado. This work complemented learning for the simulation in capstone. In the simulator we were separated in 3 teams and we took business decisions regarding innovation, product design, sales, marketing, human resources, production and operations, installed capacity and finance. In the case of these weekly deliverables I developed the subjects using a plan for the creation of a Hotel in Ensenada Baja California in Mexico.ITESO, A.C.REGI