877 resultados para Stationary


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Today, renewable energy technologies and modern power electronics have made it feasible to implement low voltage direct current (LVDC) microgrids (MGs) ca-pable to island operation. Such LVDC networks are particularly useful in remote areas. However, there are still pending issues in island operated LVDC MGs like electrical safety and controlled operation, which should be addressed before wide-scale implementation. This thesis is focused on the overall protection of an island operated LVDC network concept, including protection against electrical shocks, mains equipment protection and protection of photovoltaic (PV) power sources and battery energy storage systems (BESSs). The topic is approached through ex-amination of the safety hazards and the appropriate methods to protect against them, comprising considerations for earthing system selection and realisation of the protection system.

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This experiment viewed to evaluate the physiological quality of grain sorghum seeds as well as to determine the respective drying curve of each of three drying methods. The seeds harvested at 18.9%, 18.1%, and 18.2% of moisture content were submitted to the following drying methods : a) under natural conditions, b) an intermittent dryer in which the combustion of firewood was the source of caloric energy, and c) a stationary dryer in which the source of caloric energy was the burning of liquefied petroleum gas. The experimental design was a completely randomized one with 25 repetitions of one hundred seeds each. The water contents and weight of one thousand seeds were evaluated. Seeds physiological quality was evaluated by germination and vigor tests. Seed drying rates were of 0.11, 1.25, and 0.55 percent points per hour (pph -1) for the natural, intermittent and stationary drying methods, respectively. The intermittent treatment permits the highest loss of water in the shortest period of time, and germination and vigor remaining unchanged.

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The objective of the present study was to evaluate the efficiency of X-rays in identifying fissures in artificially dried rice seeds and the relationship between damage and seed performance in the germination test. Irrigated rice seeds of the IRGA 417 and IRGA 420 cultivars were harvested with 23.3 and 24.5% water content respectively and submitted to stationary drying treatments at 32, 38, 44 and 50 °C. X-rays were taken of subsamples of 100 seeds for each treatment, using an MX-20 X-ray equipment. The X-rayed seeds were classified from 1 to 3, where 1 corresponded to seeds without fissures, 2 to seeds with non-severe fissures and 3 to seeds with severe fissures. The same X-rayed seeds were planted and on the seventh day the seedlings (normal or abnormal) and dead seeds were photographed and evaluated to verify any relationship between the fissures and physiological potential. Higher drying temperature increased the percentage of fissures in the two cultivars, which can adversely affect their germination. Seeds with fissures can be identified using X-rays.

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The paper presents both the New Consensus and Keynesian equilibrium within the usual four competitive macro-markets structure. It gives theoretical explanations of the pernicious effects that the NCM governance, which has been designed for ergodic stationary regimes, brings about in Keynesian non-ergodic regimes. It put forward Keynesian principles of governance which include monetary, budgetary and fiscal instruments, and suggest new directions for the positive and normative analysis of macro-policies.

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Suuri osa käytössä olevista lääkeaineista on kiraalisia yhdisteitä. Lääkevalmisteet sisältävät yhdisteen enantiomeerien ominaisuuksista riippuen joko yksittäistä enantiomeeria tai näiden seosta. Antitromboottisiin eli veren hyytymistä estäviin lääkeaineisiin kuuluvat varfariini ja rivaroksabaani ovat kiraalisia yhdisteitä, joiden enantiomeerien ominaisuudet poikkeavat antitromboottisen vaikutuksen voimakkuuden suhteen. Varfariinia käytetään kliinisesti enantiomeeriensa raseemisena seoksena, kun taas rivaroksabaani on käytössä lääkevalmisteena puhtaana S-enantiomeerinaan. Lääkeaineen enantiomeerien erottaminen toisistaan on tärkeää esimerkiksi enantiomeerien puhdistamiseksi, lääkevalmisteen oikean koostumuksen varmistamiseksi tai yksittäisten enantiomeerien käyttäytymisen arvioimiseksi elimistössä. Tässä kirjallisuustyössä käsiteltiin nestekromatografian käyttöä antitromboottisiin lääkeaineisiin kuuluvien antikoagulanttien enantiomeerien fraktioinnissa. Kirjallisuudesta saadun tiedon perusteella arvioitiin, millä erotusmateriaaleilla ja millaisissa koeolosuhteissa varfariinin sekä rivaroksabaanin enantiomeerit tulisi erottaa toisistaan. Varfariinin enantiomeerien erotukseen parhaiten sopivaksi erotusmateriaaliksi todettiin kirjallisuuden perusteella kiraalinen vankomysiinipohjainen stationaarifaasi (Chirobiotic V) metanolin, etikkahapon ja veden seoksen toimiessa eluenttina. Eluentin virtausnopeudella 0,3 mL/min ja pienellä injektiotilavuudella varfariinin enantiomeerit saatiin erottumaan täydellisesti ja nopeasti toisistaan. Kirjallisuuden perusteella rivaroksabaanin enantiomeerien erotuksessa erotusmateriaalina toimii parhaiten kiraalinen selluloosapohjainen stationaarifaasi (Chiralcel OD-RH), kun eluenttina käytetään n-heksaanin ja isopropanolin seosta virtausnopeudella 1 mL/min. Varfariinin ja rivaroksabaanin enantiomeerien fraktiointiin parhaiten sopivia menetelmiä voidaan käyttää eri tilanteissa, kuten lääkevalmisteiden laadunvarmistuksessa tai enantiomeerien erotuksessa niiden synteesin jälkeen.

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Human-Centered Design (HCD) is a well-recognized approach to the design of interactive computing systems that supports everyday and professional lives of people. To that end, the HCD approach put central emphasis on the explicit understanding of users and context of use by involving users throughout the entire design and development process. With mobile computing, the diversity of users as well as the variety in the spatial, temporal, and social settings of the context of use has notably expanded, which affect the effort of interaction designers to understand users and context of use. The emergence of the mobile apps era in 2008 as a result of structural changes in the mobile industry and the profound enhanced capabilities of mobile devices, further intensify the embeddedness of technology in the daily life of people and the challenges that interaction designers face to cost-efficiently understand users and context of use. Supporting interaction designers in this challenge requires understanding of their existing practice, rationality, and work environment. The main objective of this dissertation is to contribute to interaction design theories by generating understanding on the HCD practice of mobile systems in the mobile apps era, as well as to explain the rationality of interaction designers in attending to users and context of use. To achieve that, a literature study is carried out, followed by a mixed-methods research that combines multiple qualitative interview studies and a quantitative questionnaire study. The dissertation contributes new insights regarding the evolving HCD practice at an important time of transition from stationary computing to mobile computing. Firstly, a gap is identified between interaction design as practiced in research and in the industry regarding the involvement of users in context; whereas the utilization of field evaluations, i.e. in real-life environments, has become more common in academic projects, interaction designers in the industry still rely, by large, on lab evaluations. Secondly, the findings indicate on new aspects that can explain this gap and the rationality of interaction designers in the industry in attending to users and context; essentially, the professional-client relationship was found to inhibit the involvement of users, while the mental distance between practitioners and users as well as the perceived innovativeness of the designed system are suggested in explaining the inclination to study users in situ. Thirdly, the research contributes the first explanatory model on the relation between the organizational context and HCD; essentially, innovation-focused organizational strategies greatly affect the cost-effective usage of data on users and context of use. Last, the findings suggest a change in the nature of HCD in the mobile apps era, at least with universal consumer systems; evidently, the central attention on the explicit understanding of users and context of use shifts from an early requirements phase and continual activities during design and development to follow-up activities. That is, the main effort to understand users is by collecting data on their actual usage of the system, either before or after the system is deployed. The findings inform both researchers and practitioners in interaction design. In particular, the dissertation suggest on action research as a useful approach to support interaction designers and further inform theories on interaction design. With regard to the interaction design practice, the dissertation highlights strategies that encourage a more cost-effective user- and context-informed interaction design process. With the continual embeddedness of computing into people’s life, e.g. with wearable devices and connected car systems, the dissertation provides a timely and valuable view on the evolving humancentered design.

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One of the fundamental problems with image processing of petrographic thin sections is that the appearance (colour I intensity) of a mineral grain will vary with the orientation of the crystal lattice to the preferred direction of the polarizing filters on a petrographic microscope. This makes it very difficult to determine grain boundaries, grain orientation and mineral species from a single captured image. To overcome this problem, the Rotating Polarizer Stage was used to replace the fixed polarizer and analyzer on a standard petrographic microscope. The Rotating Polarizer Stage rotates the polarizers while the thin section remains stationary, allowing for better data gathering possibilities. Instead of capturing a single image of a thin section, six composite data sets are created by rotating the polarizers through 900 (or 1800 if quartz c-axes measurements need to be taken) in both plane and cross polarized light. The composite data sets can be viewed as separate images and consist of the average intensity image, the maximum intensity image, the minimum intensity image, the maximum position image, the minimum position image and the gradient image. The overall strategy used by the image processing system is to gather the composite data sets, determine the grain boundaries using the gradient image, classify the different mineral species present using the minimum and maximum intensity images and then perform measurements of grain shape and, where possible, partial crystallographic orientation using the maximum intensity and maximum position images.

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Factors affecting the detennination of PAHs by capillary GC/MS were studied. The effect of the initial column temperature and the injection solvent on the peak areas and heights of sixteen PAHs, considered as priority pollutants, USillg crosslinked methyl silicone (DB!) and 5% diphenyl, 94% dimethyl, 1% vinyl polysiloxane (DBS) columns was examined. The possibility of using high boiling point alcohols especially butanol, pentanol, cyclopentanol, and hexanol as injection solvents was investigated. Studies were carried out to optimize the initial column temperature for each of the alcohols. It was found that the optimum initial column temperature is dependent on the solvent employed. The peak areas and heights of the PAHs are enhanced when the initial column temperature is 10-20 c above the boiling point of the solvent using DB5 column, and the same or 10 C above the boiling point of the solvent using DB1 column. Comparing the peak signals of the PAHs using the alcohols, p-xylene, n-octane, and nonane as injection solvents, hexanol gave the greatest peak areas and heights of the PAHs particularly the late-eluted peaks. The detection limits were at low pg levels, ranging from 6.0 pg for fluorene t9 83.6 pg for benzo(a)pyrene. The effect of the initial column temperature on the peak shape and the separation efficiency of the PARs was also studied using DB1 and DB5 columns. Fronting or splitting of the peaks was obseIVed at very low initial column temperature. When high initial column temperature was used, tailing of the peaks appeared. Great difference between DB! and.DB5 columns in the range of the initial column temperature in which symmetrical.peaks of PAHs can be obtained is observed. Wider ranges were shown using DB5 column. Resolution of the closely-eluted PAHs was also affected by the initial column temperature depending on the stationary phase employed. In the case of DB5, only the earlyeluted PAHs were affected; whereas, with DB1, all PAHs were affected. An analytical procedure utilizing solid phase extraction with bonded phase silica (C8) cartridges combined with GC/MS was developed to analyze PAHs in water as an alternative method to those based on the extraction with organic solvent. This simple procedure involved passing a 50 ml of spiked water sample through C8 bonded phase silica cartridges at 10 ml/min, dried by passing a gentle flow of nitrogen at 20 ml/min for 30 sec, and eluting the trapped PAHs with 500 Jll of p-xylene at 0.3 ml/min. The recoveries of PAHs were greater than 80%, with less than 10% relative standard deviations of nine determinations. No major contaminants were present that could interfere with the recognition of PAHs. It was also found that these bonded phase silica cartridges can be re-used for the extraction of PAHs from water.

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Factors involved in the determination of PAHs (16 priority PAHs as an example) and PCBs (10 PCB congeners, representing 10 isomeric groups) by capillary gas chromatography coupled with mass spectrometry (GC/MS, for PAHs) and electron capture detection (GC/ECD , for PCBs) were studied, with emphasis on the effect of solvent. Having various volatilities and different polarities, solvent studied included dichloromethane, acetonitrile, hexan e, cyclohexane, isooctane, octane, nonane, dodecane, benzene, toluene, p-xylene, o-xylene, and mesitylene. Temperatures of the capillary column, the injection port, the GC/MS interface, the flow rates of carrier gas and make-up gas, and the injection volume were optimized by one factor at a time method or simplex optimization method. Under the optimized conditions, both peak height and peak area of 16 PAHs, especially the late-eluting PAHs, were significantly enhanced (1 to 500 times) by using relatively higher boiling point solvents such as p-xylene and nonane, compared with commonly used solvents like benzene and isooctane. With the improved sensitivity, detection limits of between 4.4 pg for naphthalene and 30.8 pg for benzo[g,h,i]perylene were obtained when p-xylene was used as an injection solvent. Effect of solvent on peak shape and peak intensity were found to be greatly dependent on temperature parameters, especially the initial temperature of the capillary column. The relationship between initial temperature and shape of peaks from 16 PAHs and 10 PCBs were studied and compared when toluene, p-xylene, isooctane, and nonane were used as injection solvents. If a too low initial temperature was used, fronting or split of peaks was observed. On the other hand, peak tailing occurred at a too high initial column temperature. The optimum initial temperature, at which both peak fronting and tailing were avoided and symmetrical peaks were obtained, depended on both solvents and the stationary phase of the column used. On a methyl silicone column, the alkane solvents provided wider optimum ranges of initial temperature than aromatic solvents did, for achieving well-shaped symmetrical GC peaks. On a 5% diphenyl: 1% vinyl: 94% dimethyl polysiloxane column, when the aromatic solvents were used, the optimum initial temperature ranges for solutes to form symmetrical peaks were improved to a similar degree as those when the alkanes were used as injection solvents. A mechanism, based on the properties of and possible interactions among the analyte, the injection solvent, and the stationary phase of the capillary column, was proposed to explain these observations. The effect of initial temperature on peak height and peak area of the 16 PAHs and the 10 PCBs was also studied. The optimum initial temperature was found to be dependent on the physical properties of the solvent used and the amount of the solvent injected. Generally, from the boiling point of the solvent to 10 0C above its boiling point was an optimum range of initial temperature at which cthe highest peak height and peak area were obtained.

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The letter is written on Waldorf-Astoria stationary. She is in the city with her Auntie and they plan to go to dinner at the Martinique. The letter is labelled number 64.

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Geography has long been a predominantly visual discipline, but recent work in geography has sought to explore the multisensory, embodied, emotional and affective dimensions of people’s relations with places. One way to engage this type of exploration is through the use of sound walks: walks along a specified route accompanied by a soundtrack (on headphones or stationary speakers) that conveys information, enacts a story, produces an ambience or atmosphere, or illuminates certain aspects of the environment through which the listener is walking. This thesis aims to show how geographers can benefit from using sound walks as thinking tools, representational tools and teaching tools. Drawing on my own experiences producing sound walks, I first examine the ways that sound walk production processes help generate productive geographical thinking for those producing sound walks (Chapter Two). The various stages of producing a sound walk require different skill sets, pose different challenges, and require different sorts of environmental awareness, and therefore present novel opportunities for developing geographical insights about specific places or spatial relations. Second, I focus on four experientially-oriented aspects of sound walks – using multiple senses, walking, contingency, and moments of interaction – to argue that sound walks can be useful representational tools for geographers, whether those creating sound walks subscribe to a representational or non-representational theory of knowledge (Chapter Three). The value of sound walks as representational tools is in the experience of ‘doing’ them. That is, audiences discover for themselves through interaction what is being represented, rather than having it delivered to them. The experiential elements of ‘doing’ sound walks recommend them as potentially helpful representational tools for geographers. Third, by examining the work of a small sample of fourth year “Advanced Geography of Music” students, I develop the argument that sound walks can be effective tools for teaching students and for creating circumstances for students to learn independently (Chapter Four). Sound walks have potential to be effective pedagogical tools because they are commensurate with several key pedagogical schools of thought that emphasise the importance of requiring students to engage actively with their environment using a combination of senses. The thesis demonstrates that sound walks are a worthwhile resource for geographers to use theoretically, representationally and pedagogically in their work. The next step is for geographers to put them into practice and realize this potential.

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Clipping regarding the original road allowance which was part of Mr. Woodruff’s property, n.d. Clipping regarding the Lock 2 Bridge. This is a letter to the editor of the Journal from Calvin Phelps of Lockport, Nov. 13, 1889. Clipping entitled “Settled beyond a Dispute”: a letter to the Editor of the Star from J. G. Currie regarding the road allowance in the 5th Concession of Grantham, Nov. 16, 1889. Clipping entitled “That Old Road Allowance” which is a rebuttal to Mr. Currie’s letter, [1889] 2 newspaper clippings regarding: “Reg. vs. Toronto Railway Company”. These 2 articles are glued to a piece of paper. Beneath the newspaper articles is the name M. Chambers, Nov. 18, 1898. Notes regarding the clippings are enclosed with the articles. These notes and written on the back of “Pattison, Collier and Shaw Barristers, Solicitors, Etc.” stationary (notes are 2 pages, handwritten), Nov. 18, 1898. Clipping entitled “History on the Site: St. Davids’ Students Learn Lessons where Events Occurred” (2 copies), n.d.

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Sweeps tickets including: an envelope that says “sweep tickets from Miss Hillman which contains a Toronto Dominion Bank envelope containing 1 Hospitals’ Trust (1940) Dublin ticket; A Toronto Dominion Bank piece of stationary containing 2 Hospitals’ Trust (1940) Dublin tickets; A Toronto Dominion Bank envelope with “Mrs. Band” written of the back, containing 2 Irish Hospitals’ Sweepstakes Tickets (1958); 1 Toronto Dominion Bank envelope with Mrs. M. W. Band typed on the front, containing 2 Irish Hospitals’ Sweepstakes Tickets (1957) and 4 Hospitals’ Trust (1940) Dublin tickets; 1 Toronto Dominion Bank envelope containing 1 Irish Hospitals’ Sweepstake ticket (1958); 1 Toronto Dominion Bank envelope containing 4 Irish Hospitals’ Sweepstakes tickets (1958) all 4 of these tickets have Margaret W. Band written on the back but one also has “Nana” and one has “Hi-Boy” also written on it, 1940, 1957-1958

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This paper studies seemingly unrelated linear models with integrated regressors and stationary errors. By adding leads and lags of the first differences of the regressors and estimating this augmented dynamic regression model by feasible generalized least squares using the long-run covariance matrix, we obtain an efficient estimator of the cointegrating vector that has a limiting mixed normal distribution. Simulation results suggest that this new estimator compares favorably with others already proposed in the literature. We apply these new estimators to the testing of purchasing power parity (PPP) among the G-7 countries. The test based on the efficient estimates rejects the PPP hypothesis for most countries.

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Presently, conditions ensuring the validity of bootstrap methods for the sample mean of (possibly heterogeneous) near epoch dependent (NED) functions of mixing processes are unknown. Here we establish the validity of the bootstrap in this context, extending the applicability of bootstrap methods to a class of processes broadly relevant for applications in economics and finance. Our results apply to two block bootstrap methods: the moving blocks bootstrap of Künsch ( 989) and Liu and Singh ( 992), and the stationary bootstrap of Politis and Romano ( 994). In particular, the consistency of the bootstrap variance estimator for the sample mean is shown to be robust against heteroskedasticity and dependence of unknown form. The first order asymptotic validity of the bootstrap approximation to the actual distribution of the sample mean is also established in this heterogeneous NED context.