Ultracapacitors Utilization for Automotive Applications

This paper describes the basic properties of ultracapacitors and a converter for ultracapacitors with application zero-voltage switching (ZVS). Because of the very high efficiency of the ultracapacitor, the efficiency of the converter for ultracapacitors also has to be high; otherwise, the converter reduces efficiency of the whole drive unit. Further, the paper describes the drive unit concept for the CityEl electric vehicle, with the use of ultracapacitors in cooperation with a fuel cell. This co-operation with ultracapacitors is useful for the supply unit as a fuel cell, which cannot deliver peak power in dynamic conditions while maintaining its nominal efficiency. However, this poses no problems for ultracapacitors.There is also a description of the basic principles of soft switching using zero-voltage and zero-current switching together with a comparison of the power losses between hard and soft switching.

Assessment of selected parameters of automatic and conventional equipment used in cattle feeding

ArticleA cattle farming is a very important sector of agriculture. In the Czech Republic, both breeds with ‘combined useful’ as well as ‘meat cattle’ are breeding, but especially ‘dairy cattle’ breeds. Providing feed at the right time, in required quantity and quality is the basis of successful breeding, especially in breeding dairy cows. Automatic systems are present in almost all sectors of human activity, and livestock production is no exception. Fully automatic feeding systems for pigs or poultry are already in use. The process of milking cattle using automated milking systems is also sufficiently mastered. An interesting trend is the installation of automated feeding systems for cattle feeding. They are stationary lines that perform the following operations: they dose the individual components of the feed mixture, mix the feed mixture and distribute it to the relevant feed places. All these activities are usually done without the presence of a person. The automated feeding system Lely Vector and the conventional feeding system using feeding wagon Cernin were compared. The number of automated feed wagon runs has been monitored and then the feed consumption was compared while using automatic and conventional equipment. The aim of this paper is to evaluate the benefits of an automatic feed system with regard to the conventional feed system through a mobile feed car

GENETSKI MODIFICIRANI ORGANIZMI I PROIZVODI U EUROPSKOM ZAKONSKOM KONTEKSTU

The article is focused on basic issues of the EU legislation in the area of GMOs and GM products. The treatment of genetically modified organisms and products has been regulated in the European Union since beginning of 90’s. The so called precautionary principle is the basic principle of EU legislation in this field. Therefore, the primary goal of legislation is to protect the environment and health. Contemporary EU legislation consists of three main groups dealing with harmonisation of authorisation procedure, labelling and traceability of GMOs and GM products and implementation of Cartagena Protocol in relation to transboundary movements of GMOs. The strict EU legal framework for GMOs has caused problems within international trade, particularly with USA, Canada and Argentina.Članak je usmjeren na osnovna pitanja zakonodavstva EU u području genetski modificiranih organizama (GMO) i genetski modificiranih (GM) proizvoda. Tretiranje GMO i GM proizvoda regulirano je u Europskoj uniji od početka 90-ih godina. Tzv. "princip opreza" je osnovni princip zakonodavstva na tom području. Stoga je prvenstveni cilj zakonodavstva zaštita okoliša i zdravlja. Suvremeno zakonodavstvo EU sastoji se od tri glavne skupine koje se bave usklađivanjem postupaka odobrenja, označavanjem i porijeklom GMO i GM proizvoda te provođenjem Protokola iz Kartage u vezi s prekograničnim kretanjima GMO-a. Strogi zakonski okviri Europske unije za GMO-e stvorili su probleme u međunarodnoj trgovini osobito s SAD-om, Kanadom i Argentino

The determination of impact of malt grist moisture on porosity and permeability using measurement of differential air pressure

ArticleThis article is focused on determination of malt grist and spent grains porosity and permeability using measurement of differential pressure of the air passing through the layer of malt grist and spent grains. For preparation of malt grist were used different disintegration equipment (two roller mill and disc mill). The method of differential pressure measuring is used for the determination of porosity of malt grist layer, defined as fraction of the volume of voids over the total volume. Measurement confirmed the logical assumption; the higher-pressure difference is above and below the spent grain layer, the lower value of porosity

On-board unit and its possibilities of communications on safety and security principles

The technical solution of on-board unit (OBU) for vehicles used for dangerous good transport and design of vehicle sensor network (based on CAN bus) for dangerous good monitoring will be discussed. In presentation the conception of GSM/GPRS networking subsystem for real time data transmission into monitoring centre will be described. Next themes of discussion will be focused on the possibilities of solution of safety-related communication channel for safety sensor network in accordance with standard for functional safety of Electrical / Electronic / Programmable Electronic (E/E/PE) systems IEC 61508 [4], recommended methods of risk analysis and possibilities of their modelling and proposal of secure communication channel over GSM/GPRS for secure data transmission into control centre on the base of IPsec protocol

Determining external friction angle of barley malt and malt crush

ArticleThis paper deals with determining the amount of external friction angle of barley malt and malt crush depending on the load size. Barley malt is a basic raw material for production of the traditional Czech Pilsner type of beer. The angle of internal and external friction is one of the basic parameters of bulk materials. Friction among individual grains of material, i.e. a connection with the forces, applied between individual material particles, includes the internal friction angle. Conversely, the external friction angle is the angle in which the bulk material begins to move on the other material (steel). A two-roll mill (or disc mill and hammer mill) was used for the malt crush manufacture, which is used in the traditional malt processing in beer production. During crushing on this machine, we used the passage of the milled material through a gap between two counter-rotating cylinders. The results of barley malt and malt crush external friction angle, depending on the load size of the barley malt and the malt crush on mobile prototype device, are from 8 to 22°. The mobile prototype device is based on the following principle: a square chamber filled with a loaded material moves on the pad (steel)

Holding the wheel in passenger cars in countries with driving on the right and left side depending on the driver’s side preference

ArticleThis paper deals with the assessment of the differences in how passenger car drivers hold a steering wheel with left and right-side steering in specific driving modes. The findings are compared to the generally-accepted optimal position in terms of active and passive safety, as well as long-term effects on the health of the driver. The research described in this work was conducted on a sample of randomly selected drivers in the Czech Republic, the UK and Australia using electronic questionnaires. The data was then subjected to a statistical evaluation, which looked primarily at the difference between the way in which the steering wheel was held in countries with driving on the right and driving on the left. Another parameter for statistical data evaluation was the used side preference of individual drivers. On the basis of a statistical evaluation of the obtained data, it was found that there is a difference in the way the steering wheel is held in the assessed traffic situations between drivers driving on the right and drivers driving on the left. The results of this work can be used in the design process of passenger car cabins, in particular in the field of adaptation of the control devices of particular models to the needs of drivers in individual countries based on the type of traffic. The results of the work point out the necessity to make innovations in the design of passenger car cabins with regard to the type of traffic in which the vehicle will be operated, which could lead to a better application of innovations, and thereby better possibilities of positively influencing traffic safety and the health of drivers

Impact of the duration of speech sequences on speech quality

This paper describes simulations of speech sequences transmission for intrusive measurement of voice transmission quality of service (VTQoS) in the environment of IP networks. The aim of the simulations was to investigate the impact of the different durations of speech sequences on speech quality from the jitter rate and packet loss point of view in IP networks. The ITU-T G.729 and ITU-T G.723.1 encoding schemes were used for the purpose of the simulations. The assessment of speech quality was realized by means of perceptual evaluation of speech quality (PESQ) algorithm. A comparison of the impact of different durations of speech sequences on speech quality and determination of the optimal duration of speech sequence for measurements of speech quality in telecommunication networks, is the aim of this paper

Influence of mixture and conditions of gelatination on properties of expanded PVC foils

The article describ es preparation of expanded PVC foils from PVC pastes by applying the blowing agent Unicel D 200A. Experimentally, effects of the type polymer and plasticizer have been proved, applied by preparation of the mixture and influence of gelatination on the foam structure