We demonstrate a modularity bug in the interface system of Java 8 on the practical example of a textbook design of a modular interface for vector spaces. Our example originates in our teaching of modular object-oriented design in Java 8 to undergraduate students, simply following standard programming practices and mathematical denitions. The bug shows up as a compilation error and should be xed with a language extension due to the importance of best practices (design delity).
We are familiar with the grammar and logic of relational predicates in predicate calculus, chiefly as transmitted through Whitehead and Russell. In natural languages however, relations are frequently expressed using what Peirce called relatives, that is, expressions like brother, gift, head, effect, successor, which require completion by one or more definite terms to yield general names or terms. Peirce developed a logic of such relatives which influenced Schröder and Tarski. Later, Leśniewski used relative terms such as part, overlapper, class etc. to formulate his mereology, rather than the predicates and operators subsequently and more standardly used. In this paper I con-sider aspects of the grammar and logic of such relative terms, particularly in regard to several areas of general logico-philosophical interest: cardinality; functions; abstrac-tion; the order problem of relations; and Russell’s multiple relation theory of belief and judgment.
Czy przed wejściem do puszczy powinina wisieć tabliczka z napisem: „Nie przeszkadzać”?
Production of spheroidal graphite cast iron is today quite mastered technology. There are many methods achieving the nodular graphite morphology. Each of these methods have specific characteristics and requirements to technical support, properties and the type of applied modifier. Selection of the spheroidization method is dependent on foundry disposition, production character, economic balance, quality requirements, etc. In case of centrifugally casting the core, which fills body and neck of the roll, is created by ductile iron. Considering the sophisticated production of centrifugally cast rolls for hot rolling mills it is necessary to ensure a high reproducibility and reliability of ductile cast iron production quality in the bulk range of 9-18 t per tapping. These conditions are in the Roll Foundry in Vítkovicke Slevarny, spol. s r.o. provided and verified mastered overpour method and the newly injection of cored wire in the melt.
Due to fast-paced technical development, companies are forced to modernise and update
their equipment, as well as production planning methods. In the ordering process, the customer
is interested not only in product specifications, but also in the manufacturing lead
time by which the product will be completed. Therefore, companies strive towards setting
an appealing but attainable manufacturing lead date.
Manufacturing lead time depends on many different factors; therefore, it is difficult to predict.
Estimation of manufacturing lead time is usually based on previous experience. In the
following research, manufacturing lead time for tools for aluminium extrusion was estimated
with Artificial Intelligence, more precisely, with Neural Networks.
The research is based on the following input data; number of cavities, tool type, tool category,
order type, number of orders in the last 3 days and tool diameter; while the only output
data are the number of working days that are needed to manufacture the tool. An Artificial
Neural Network (feed-forward neural network) was noted as a sufficiently accurate method
and, therefore, appropriate for implementation in the company.
The new topology of three-winding welding transformer is proposed. Each secondary winding is connected in parallel through the separate bridge rectifier to the welding arc. The main feature of the proposed device is parallel working of two secondary windings with different rated voltage. The advantage is nonlinear transformation ratio of current that provides unprecedented power efficiency. The self- and mutual leakage inductances, which are important in power conversion, are calculated by 2D FEA model. The operational current of the device is modelled numerically via P-Spice simulator. The proposed topology is up to 30% more power effective than conventional welding transformer provided that the leakage inductances of primary and secondary windings are correctly fitted. This transformer is used for manual arc welding.
Beamforming is an advanced signal processing technique used in sensor arrays for directional signal transmission
or reception. The paper deals with a system based on an ultrasound transmitter and an array of
receivers, to determine the distance to an obstacle by measuring the time of flight and – using the phase
beamforming technique to process the output signals of receivers for finding the direction from which the
reflected signal is received – locates the obstacle. The embedded beam-former interacts with a PID-based
line follower robot to improve performance of the line follower navigation algorithm by detecting and
avoiding obstacles. The PID (proportional-integral-derivative) algorithm is also typically used to control
industrial processes. It calculates the difference between a measured value and a desired set of points, then
attempts to minimize the error by adjusting the output. The overall navigation system combines a PID-based
trajectory follower with a spatial-temporal filter (beamformer) that uses the output of an array of sensors to
extract signals received from an obstacle in a particular direction in order to guide an autonomous vehicle
or a robot along a safe path.
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