221 research outputs found
A Way to Use Waste Heat to Generate Thermoelectric Power
In recent years there has been rising interest in thermoelectric generation as a potential source of electric power using waste heat. This paper describes thermoelectric power generation from waste heat from biomass boilers, utilizing generators that can convert heat energy directly to electrical energy. General principles of thermoelectric conversion and future prospects of these applications are discussed
EFFECT OF TUBE PITCH ON HEAR TRANSFER IN SPRINKLED TUBE BUNDLE
Water flowing on a sprinkled tube bundle forms three basic modes: the Droplet mode (the liquid drips from one tube to another), the Jet mode (with an increasing flow rate, the droplets merge into a column) and the Membrane (Sheet) mode (with a further increase in the flow rate of the falling film liquid, the columns merge and create sheets between the tubes. With a sufficient flow rate, the sheets merge at this stage, and the tube bundle is completely covered by a thin liquid film). There are several factors influencing both the individual modes and the heat transfer. Beside the above-mentioned falling film liquid flow rate, these are for instance the tube diameters, the tube pitches in the tube bundle, or the physical conditions of the falling film liquid. This paper presents a summary of data measured at atmospheric pressure, with a tube bundle consisting of copper tubes of 12 millimetres in diameter, and with a studied tube length of one meter. The tubes are situated horizontally one above another at a pitch of 15 to 30 mm, and there is a distribution tube placed above them with water flowing through apertures of 1.0mm in diameter at a 9.2mm span. Two thermal conditions have been tested with all pitches: 15 °C to 40 °C and 15 °C to 45 °C. The temperature of the falling film liquid, which was heated during the flow through the exchanger, was 15 °C at the distribution tube input. The temperature of the heating liquid at the exchanger input, which had a constant flow rate of approx. 7.2. litres per minute, was 40 °C, or alternatively 45 °C
Substance Abuse, Social Values Change and Acceleration of Family Destabilization
Background: Substance abuse has the potential to change value orientations and affects all aspects of human life.Objectives: The text aims to show the shift in value orientations of respondents who use addictive substances compared to respondents who do not.Methodology: One-way ANOVA was used in the statistical analysis of the dependence of the values on the occurrence of abusive behaviour, with dependencies at the level of p ≤ 0.05 considered statistically significant.Results: There were statistically significant differences between the group of respondents with abstinence from each addictive substance and the group of respondents without abstinence. Substance abuse shifts pro-family values towards greater individualization and thus threatens and destabilizes the family. It strengthens community-oriented values and weakens family-oriented values.Conclusions: The transformation of the value system leads to a destabilization of family ties, which cease to be a priority. Working with values should be an opportunity for social pedagogy, social work, and all types of schools. Non-formal and informal education present particular opportunities for values education. In many cases, it is unnecessary to change the value system, but only to show the non-deviant way of fulfilling values
Minimal Detectable Displacement Achievable by GPS-RTK in CZEPOS Network
In this paper we have made a brief study of RTK precision to estimate possibilities of network RTK using CZEPOS for purposes of geotechnic monitoring of landslides in real time. In this paper we describe a testing methodology, which resulted in estimation of point-position precision and describing minimal detectable positional change. Based on our results it is concluded that displacements could be detected with centimetre accuracy even with short-period observations
Education as a prevention of fraud
A critical way of thinking developed by teachings of financial audit, accounting and taxation are necessary for any graduate in economics. Combined with ethics it is the essential prerequisite for increasing the resistance of the experts to embezzlement. The aim of this study is to ascertain whether the graduates of business schools in Czech Republic are ready to recognize and expose economic crime/fraud which they might encounter at their workplace. The readiness of the graduates is bilateral as it includes the ability "to recognize" which is discussed in terms of adequate knowledge - which should be obtained especially during the bachelor and master studies, and the willingness "to expose" which is discussed in terms of moral principles of the graduates - which should be augmented during their studies as well. The article summarizes the results of research conducted among Czech universities and their graduates. The research among the Czech universities was carried out as an analysis of the study programs provided by Czech universities and the corresponding syllabi. The research among the graduates was carried out via online questionnaire distributed to graduates through their alumni organizations. This questionnaire was accessible through the Internet from November 2014 to February 2015. During this period 264 respondents undertook the survey. We formulate two theses in this paper. First thesis states that Czech graduates are not equipped with knowledge necessary to recognize economic fraud at their workplace. Second thesis states that Czech graduates don't possess the moral incentives to expose the economic crime. While we were not able to confirm the first thesis unequivocally, we concluded that there is much to improve in the structure of the study programs of Czech universities providing business education. The second thesis was confirmed though. The suggestions we made in this paper based on the research were the following: firstly, to develop a syllabus of a new teaching subject which would incorporate the basic aspects of the advanced financial accounting, auditing, tax and business law and make such subject mandatory for all business graduates at Czech universities. Similar subject - even though less extensive/complex - shall be developed for the secondary business schools as well. Secondly, to eliminate the segmented ethics of secondary school graduates through education based on case-studies and demonstration and focus greatly on raising the ethics standards at both levels of business education.This paper is not a traditional field-based research study. Rather it is a summary/conclusive report on two interconnected research projects. The aim of this paper is to summarize the results from the former research projects and to compare andto confront the findings of these projects in the attempt to find a “common denominator” of both issues raised in the preceding research projects
Advanced Methods of Audio Signals Interpolation
Tato diplomová práce se zabývá teoretickým rozborem predikční metody interpolace signálu a modelováním signálu pomocí sinusoidálního modelu. Na základě této teorie je ve výpočetním prostředí MATLAB realizován algoritmus pro rekonstrukci chybějících úseků ve zvukovém signálu. Pomocí hromadného testování jsou zobrazeny výsledky rekonstrukce pomocí objektivních metod SNR a PEMO-Q. Dále jsou provedeny experimenty na konkrétních signálech a popsáno jejich vyhodnocení.This diploma thesis deals with the theoretical analysis of the predictive methods of signal interpolation and signal modeling using sinusoidal model. On the basis of this theory the algorithm for the reconstruction of the missing sections in the audio signal is implemented in computing environment MATLAB. Results of mass testing reconstructions are displayed using objective methods SNR and PEMO-Q. Further experiments are carried out on single signals and their evaluation is described.
Wireless temperature measurement prepared food
Tato bakalářská práce má za cíl kontaktní měření teploty, následné vyhodnocení a bezdrátový přenos informací. Teoretická část pojednává o základních vlastnostech a funkcích mikrokontroléru a bezdrátové komunikace. V praktické části byla vyřešena úloha měření teploty připravovaného pokrmu sestrojením jehly obsahující digitální teplotní čidlo. Vyhodnocení bylo provedeno pomocí A/D převodníku mikrokontroléru ATmega8 – L, který zajišťuje i funkci řídící jednotky. Bezdrátový přenos dat byl realizován pomocí technologie Bluetooth. Pro možnost okamžitého zobrazení teploty uživateli byl použit sedmisegmentový LED displej. Součástí realizace byl návrh plošného spoje a sestrojení prototypu.The goals of this bachelor's thesis are temperature measurment, data elaboration and wireless data transfer. Theoretical part introduces basic properties and functions of microcontroller and wireless communication. In practial part of this bachelor's thesis is solved temperature measurment task by construction of holow needle with digital sensor inside. Data elaboration is done by A/D converter in ATmega8 – L microcontroller. Wireless data tranfer was done by Bluetooth technology. For the purposes of immediate temperature control was included seven segment LED display. Part of realisation was to design printed circuit board and prototype assembly.
Psychological changes which occur during survival training
Nazev prace Aktualni zmeny psychickeho stavu behem kurzu pfeziti Cil prace Cilem prace bylo zjistit vliv kurzu pfeziti na psychiku jedincu, ktefi se tohoto kurzu zucastnili. Pfedmetem prace bylo i hodnoceni, do jake miry ovlivfiuji jednotlive faktory dotazniku POMS psychicky stav jedincu. V neposledni fade byl sledovan vek, pocet odslouzenych let a zkusenost ve vztahu k temto faktorum. Metoda Pfedlozena diplomova prace je zpracovana ve forme pilotni studie. Byl sestaven dotaz- nik pro sber dat, ktery byl rozdelen do dvou casti. Prvni cast Ize charakterizovat jako nestandardizovanou, kdy respondenti odpovidali na soubor otazek. Ziskane informace byly pouzity pro doplneni tohoto experimentu. Dotaznik typu POMS tvofil druhou cast, ve ktere jedinci pouze hodnotili miru svych pocitu. Na zaklade obdrzenych dat by mely byt definovany hlavni faktory ovlivnujici zmenu psychickeho stavu jedincu behem kur- zu pfeziti. Pro zjisteni pficinnych vztahu mezi studovanymi promennymi byl vyuzit kvaziexperiment a sber dat probihal formou dotaznikoveho setfeni. Vysledky Mezi zjistenymi vysledky byly nejvice patrne rozdily ve zkusenosti jednotlivcu, kdy vice zkuseni jedinci vykazovali vyssi miru psychicke stability ve vsech sledovanych faktorech. Dale se ukazalo, ze stafi jedincu ma prokazatelne vetsi vliv na jednotlive...Title Psychological Changes which Occur during Survival Training The objective of the thesis My thesis aims to examine the influence of survival training on the mental state of the participants. Another objective was to assess the extent to which each of the factors in the POMS questionnaire affects the mental state of the participants. Among others, age, number of years in service and experience in relation to these factors were studied. Method The thesis is approached as a pilot study. A questionnaire was framed and divided into two parts. The first one, in which the respondents answered a set of questions, could be characterized as non-standardized. The obtained data were used as a supplement to the experiment. The second part is formed by a POMS questionnaire in which the respon- dents only stated the extent of their emotions. The obtained data formed a basis for the definition of main factors influencing psychological changes in the survival trainees. The causal relationships between the relevant variables were discovered using a quasi experiment and data were collected through a questionnaire survey. Results The results have proved that it is the experience of the participants that shows the most significant discrepancies with the more experienced participants being more stable in all the...Vojenská tělovýchovaFaculty of Physical Education and SportFakulta tělesné výchovy a sport
Hobby cnc milling machine
Tato diplomová práce slouží jako experimentální ověření 3D návrhu hobby CNC frézky za použití dílů vytisknutých na 3D tiskárně z materiálu ABS. Práce je pojata jako úvod širší veřejnosti do problematiky CNC frézek a 3D tisku a následně jako návod ke konstrukci vlastní frézky. Důraz byl kladen na co nejnižší cenu při zachování dostatečné přesnosti a dostupnost dílů.This diploma thesis serves as experimental proof of real world capabilities of computer designed hobby CNC milling machine with its parts printed on a 3D printer. First half is a brief introduction of CNC technologies to non-professional audience. Second part together with 3D model works as manual to build your own machine. Priority was to keep costs to minimum with decent accuracy still in mind.
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