Search results for " STANDARDS"
showing 10 items of 343 documents
A device for PV modules I-V characteristic detection
2013
In this paper an electronic load suitable for the PV module I-V characteristic curve fast detection is presented. This device is designed in agreement with the IEC 82 Techinical Committee Standard since it allows the detection of the characteristic starting from voltage values even lower than 3% of the PV module open circuit voltage. The device main features are short time characteristc detection (2 s), limited ripple of the detected characteristic and low cost. Its validation is carried out by comparing measured data with data from simulations. Simulations are carried out considering two different commercial PV modules and by implementing in Matlab-Simulink environment the four lumped para…
<title>Safety problems in free space optical transmission</title>
2006
The paper is focused on safety of exploitation of optical transmission devices in free space. The subjects concerning propagation of "open" optical stream and its' possible dangerous influence on environment, mainly living organisms are discussed. An attempt to evaluate an installation and exploitation of transmitting devices was made, concerning dangers, requirements, recommendations and restrictions, concluding from accepted safety standards (IEC 60825- 1 :2005, EN 60825-1 :2005 and in Poland PN-EN 60825-1 :2005 "Safety of laser devices - Equipment classification, requirements and user's guide"; IEC 60825-12:2004, EN 60825-12:2005 and in Poland PN-EN 60825-12:2005 "Safety of free space op…
Feasibility of Body-centric Systems by Using passive textile RFID tags
2012
Recent progresses in the design of wearable RFID-tag antennas stimulate the idea of passive body-centric systems, wherein the required power to drive the wearable tags is directly scavenged from the interrogation signal emitted by the reader unit. While active body-centric links have been extensively investigated, the feasibility of passive systems is still questionable, due to the poor sensitivity of the tags and due to the modest reading distances. This paper describes a systematic measurement campaign involving low-profile wearable textile tags in the UHF RFID band. It was demonstrated that both on-body and off-body links are affordable, with a power budget fully compliant with the avail…
Izcilu studentu angļu valodas kā svešvalodu apguves daudzveidība
2021
Maģistra darba izvēlētā tēma ir aktuāla un nozīmīga, jo eksistē daudz un dažādas pieejas(problēmas) angļu valodas kā otrās valodas apguvē, bet tai pat reizē nav tādu kopēju vadlīniju , kas palīdzētu mūsdienu skolotājam risināt šīs problēmas. Šī darba mērķis bija analizēt un interpretēt angļu valodas apguves veidus, ko izmanto skolēni,kas sasnieguši labus rezultātus angļu valodas kā otrās valodas apguvē, kā arī lai noskaidrotu virzienus izvērstiem pētījumiem par efektīvas apguves rādītājiem. Darbā autors apkopojis un analizējis dažādās pieejas angļu valodas kā otrās valodas apguvē,sniedz pātnieciski pamatotus ieteikumus-vadlīnijas kā analizēt mācīšanas un mācīšanās procesus,veicis praktisku …
Analysis of Spatial Disparities by a Structural Equations Model
2008
This paper presents a new analytical framework for assessing spatial disparities among countries. It takes for granted that the analysis of a country’s performance cannot be limited solely to either economic or social factors. The aim of the paper is to combine relevant economic and non-economic (mainly social) aspects of a country’s performance in an integrated logical framework. Based on this idea, a structural simultaneous equation model will be presented and estimated in order to explore the direction of the causal relationship between the economic and the non-economic aspects of a country’s performance. Furthermore, an exploration of the trajectory that each country has registered over…
Stability of nitroaromatic specialty explosives in reversed-phase liquid chromatographic systems
2008
Abstract In this study, the stability of 2,4-dinitroanisole, 2,2′,4,4′,6,6′-hexanitrodiphenylsulfide, 2,3,4,6-tetranitroaniline, 2,4,6-trinitroaniline, 2,4,6-trinitroanisole, and 2,4,6-trinitrochlorobenzene in liquid chromatographic systems was studied under different solvent/eluent conditions. Stock solutions of the explosives were prepared in acetonitrile and diluted with acetone/water, acetonitrile/water, or methanol/water mixtures. Within 48 h, these working solutions were repeatedly injected onto a silica column and eluted with acetonitrile/water or methanol/water mobile phases. Under all conditions, 2,4-dinitroanisole was stable, whereas 2,4,6-trinitroaniline was stable only in the me…
Photo-induced fluorescence of magnesium derivatives of tetracycline antibiotics in wastewater samples
2009
Abstract An analytical strategy, for the determination of tetracyclines (TCs), based on a HPLC system coupled with a photo-reactor followed by post-column derivatization was developed. Higher fluorescence emission after coupling the resulting photo-fragments with magnesium ions was observed for the determination of minocycline (MC), epitetracycline (ETC), tetracycline (TC) and doxycycline (DC). The manifold included a HPLC system with a photo-reactor (PTFE tubing helically coiled around a low-pressure mercury lamp), a mixing T-piece and a fluorescence detector. The derivatization reagent was delivered at 0.5 mL min −1 by a pump. After HPLC separation using a gradient system with a mobile ph…
Microbial environmental contamination in Italian dental clinics: A multicenter study yielding recommendations for standardized sampling methods and t…
2012
A microbiological environmental investigation was carried out in ten dental clinics in Italy. Microbial contamination of water, air and surfaces was assessed in each clinic during the five working days, for one week per month, for a three-month period. Water and surfaces were sampled before and after clinical activity; air was sampled before, after, and during clinical activity. A wide variation was found in microbial environmental contamination, both within the participating clinics and for the different sampling times. Before clinical activity, microbial water contamination in tap water reached 51,200cfu/mL (colony forming units per milliliter), and that in Dental Unit Water Systems (DUWS…
The Effects of IFRS Adoption on the Unconditional Conservatism of Spanish Listed Companies
2017
This paper analyses the effects on unconditional conservatism of the mandatory adoption of International Financial Reporting Standards (IFRS) by Spanish listed companies in January 2005. The lack of robustness in the previous evidence justifies analysing this issue from different perspectives. To this end, we use, for the first time in this context, Ahmed and Duellman’s methodology (J. Account. Econ., 2007). In its design, these authors consider the impact of growth options and other future incomes, controlling for the idiosyncratic factors that the literature has found to condition this type of conservatism. Additionally, beyond the pooled regression techniques usually used, we use econome…
Understanding the Consequences of Accounting Standards in Europe: The Role of EFRAG
2012
The global financial crisis has accelerated the need for standard-setters to demonstrate that they understand the effects of the accounting standards they are setting. Within a European context, the endorsement process and the ultimate adoption of new and amended International Financial Reporting Standards into European Union law demand that there is evidence to support the assertion that such standards will improve financial reporting. Our analysis is anchored in the ideology theory of regulation which provides a compelling case for effect analysis to underpin the standard-setting process. For that process to work effectively, a number of key actors need to engage in the process. According…