Marginal cost-based pricing of distribution: a case study

This paper presents results of a software development project carried out by the “Electricity North West” (ENW) and “TNEI” to find economic use-of-system charges for the extra high-voltage (EHV) network. Several cost-based charging models which satisfy principles set by the Regulator, such as cost reflectivity, predictability, stability and transparency were developed. In this paper, the emphasis is put on the developed software and the comparison of nodal marginal charges obtained from the proposed pricing models

Hybrid Deterministic-Stochastic Methods for Data Fitting

Many structured data-fitting applications require the solution of an optimization problem involving a sum over a potentially large number of measurements. Incremental gradient algorithms offer inexpensive iterations by sampling a subset of the terms in the sum. These methods can make great progress initially, but often slow as they approach a solution. In contrast, full-gradient methods achieve steady convergence at the expense of evaluating the full objective and gradient on each iteration. We explore hybrid methods that exhibit the benefits of both approaches. Rate-of-convergence analysis shows that by controlling the sample size in an incremental gradient algorithm, it is possible to maintain the steady convergence rates of full-gradient methods. We detail a practical quasi-Newton implementation based on this approach. Numerical experiments illustrate its potential benefits.Comment: 26 pages. Revised proofs of Theorems 2.6 and 3.1, results unchange

The Possibility of Contamination of Deep Frozen Bull Semen During Long Periods of Storage in Containers with Liquid Nitrogen

Preservation of bull sperm by deep freeze is a technological process that allows you to store semen in theory for an unlimited period of time, national and international transport, without significant loss of quality and safety of semen. According to the literature, some microorganisms successfully survive the low temperatures during storage of semen in liquid nitrogen (-196 ° C), in deep-frozen semen, seeds, and in liquid nitrogen and ice sediment in the storage container for deep-frozen bull semen. The aim of this study was to do microbiological analysis of samples semen frozen bull and liquid nitrogen in containers for bull semen storage. 414 samples of frozen bull semen, and 53 samples of liquid nitrogen ice sediment were examined. From the deeply frozen semen were isolated Candida albicans, Citrobacter freundii and Pseudomonas stutzeri. Microorganisms isolated from the storage container of frozen semen are mostly members of the family Enterobacteriacae, and Citrobacter freundii was isolated from the largest number of samples. Considering the findings of microorganisms in the semen, and liquid nitrogen, there is the possibility of connection of contamination of the semen with microorganisms of the liquid nitrogen, and reversely, as would be the goal of our future investigations

Cochlear implantation in post-lingually deafened adults and elderly patients: analysis of audiometric and speech perception outcomes during the first year of use

Questo studio è volto alla valutazione degli outcomes audiometrici e logopedici dei pazienti anziani portatori di impianto cocleare durante il primo anno di utilizzo del dispositivo. Sono stati valutati 42 pazienti impiantati tra marzo 2010 e settembre 2014 presso lUO ORL dellAzienda Ospedaliera Universitaria di Padova. Sono stati inclusi nello studio pazienti affetti da sordità bilaterale postlinguale di grado severo-profondo impiantati unilateralmente. I soggetti sono stati divisi in tre gruppi in base allepoca della chirurgia: 14 soggetti con impianto fra i 35 e i 49 anni, 14 fra i 50 e i 64 anni e 14 impiantati a unetà superiore di 65 anni. Tutti i pazienti sono stati valutati prima e dopo la chirurgia (a 1, 3, 6 e 12 mesi di follow-up) attraverso lesecuzione di: audiometria tonale, audiometria vocale, test logopedici e somministrazione del questionario delle categorie percettive (CAP). Lanalisi statistica è stata effettuata attraverso il Students t-test. La totalità dei soggetti nei tre gruppi hanno dimostrato significativi miglioramenti allaudiometria tonale e vocale ai controlli post chirurgici rispetto alle performance ottenute precedentemente allimpianto. In particolare si sono verificati miglioramenti della soglia audiometrica media (PTA) senza differenze statisticamente significative tra i tre gruppi. risultati ottenuti nei test logopedici e dalla somministrazione del CAP hanno dimostrato evidenti miglioramenti in tutti i tre gruppi in studio. Abbiamo riscontrato, però, che i soggetti più giovani hanno raggiunto maggiori punteggi ai controlli post impianto rispetto a quelli più anziani. Concludendo, possiamo affermare che limpianto cocleare è un trattamento efficace per soggetti affetti da ipoacusia severa-profonda senza differenze significative nelle performance audiologiche e logopediche in relazione alletà di impianto. Anche se più lentamente, i pazienti impiantati dopo i 65 anni di età raggiungono performance ottimali e possono essere ritenuti dei candidati ottimali allintervento

Prirodna mikobiota i prisustvo aflatoksina B1 u polenu prikupljenom u Srbiji

Total fungal count, incidence of fungi and aflatoxin B1 (AFB1) concentration were studied in 33 samples of bee pollen randomly collected from beekeepers in Serbia. The total number of fungi was determined by dilution method whereas AFB1 was detected using the Enzyme-Linked Immuno-Sorbent Assay (ELISA). The mycological estimation showed the presence of nine genera of fungi as followed: Acremonium, Alternaría, Aspergillus, Cladosporium, Epiccocum, Fusarium, Mucor, Pénicillium and Rhizopus, with total number ranging from 1 x 103 to 1 x 105 CFU g-1. The results have shown the predominance of the fungi from the genera Aspergillus and Alternaria. Among Aspergillus species it was observed that the most frequent species was A. flavus with incidence of 27.27 %. Mycotoxin AFB1 was detected as 100% positive in all samples (100%) with an average concentration of 8.61 μg kg-1. The obtained results indicated that honey bee pollen must be strictly controlled during its manipulation in the harvesting and manufacturing. Therefore, the implementation of good manufacturing (beekeeping) practice to define procedures for honeybee products could be crucial to reduce the risk of possible contamination and provide natural and safety product without risk on the human health.Ukupan broj gljiva, učestalost (incidenca) gljiva i koncentracija aflatoksina B1 (AFB1) ispitivani su u 33 uzoraka polena sakupljenih od pčelara iz različitih regiona u Srbiji. Ukupan broj gljiva određen je primenom metode razređenja a AFB1 je određen primenom imunoadsorpcione enzimske metode (ELISA). Mikološkim ispitivanjima identifikovano je devet rodova gljiva: Acremonium, Alternaria, Aspergillus, Cladosporium, Epiccocum, Fusarium, Mucor, Penicillium i Rhizopus, sa ukupnim brojem od 1 x 103 to 1 x 105 CFU g-1. Najučestalije vrste gljiva su u rodovima Aspergillus i Alternaria. Među Aspergillus vrstama najučestalija je vrsta A. flavus sa incidencom od 27,27%. AFB1 je detektovan u svim uzorcima sa prosečnom koncentracijom od 8,61 μg kg-1. Dobijeni rezultati ukazuju da pčelarski polen mora biti strogo kontrolisan tokom prikupljanja i njegove dalje prerade. Zbog toga, sprovođenje dobre proizvođačke (pčelarske) prakse podrazumeva definisanje procedura za pčelarske proizvode što bi moglo biti presudno za smanjenje rizika od moguće kontaminacije i dobijanje prirodnih i bezbednih proizvoda bez rizika po zdravlje ljudi

Circle grid fractal plate as a turbulent generator for premixed flame: an overview

This review paper focuses to ascertain a new approach in turbulence generation on the structure of premixed flames and external combustion using a fractal grid pattern. This review paper discusses the relationship between fractal pattern and turbulence flow. Many researchers have explored the fractal pattern as a new concept of turbulence generators, but researchers rarely study fractal turbulence generators on the structure premixed flame. The turbulent flow field characteristics have been studied tand investigated in a premixed combustion application. In terms of turbulence intensity, most researchers used fractal grid that can be tailored so that they can design the characteristic needed in premixed flame. This approach makes it extremely difficult to determine the exact turbulent burning velocity on the velocity fluctuation of the flow. The decision to carry out additional research on the effect circle grid fractal plate as a turbulent generator for premixed flame should depends on the blockage ratio and fractal pattern of the grid. 1

Mirror Descent and Convex Optimization Problems With Non-Smooth Inequality Constraints

We consider the problem of minimization of a convex function on a simple set with convex non-smooth inequality constraint and describe first-order methods to solve such problems in different situations: smooth or non-smooth objective function; convex or strongly convex objective and constraint; deterministic or randomized information about the objective and constraint. We hope that it is convenient for a reader to have all the methods for different settings in one place. Described methods are based on Mirror Descent algorithm and switching subgradient scheme. One of our focus is to propose, for the listed different settings, a Mirror Descent with adaptive stepsizes and adaptive stopping rule. This means that neither stepsize nor stopping rule require to know the Lipschitz constant of the objective or constraint. We also construct Mirror Descent for problems with objective function, which is not Lipschitz continuous, e.g. is a quadratic function. Besides that, we address the problem of recovering the solution of the dual problem

Low-cost workbench client / server cores for remote experiments in electronics

This paper offers an open-source solution to implement low-cost workbenches serving a wide range of remote experiments in electronics. The proposed solution comprises 1) a small (9,65 x 6,1 cm) Linux server board; 2) a server core supporting two TCP/IP communication channels, and general purpose I/O pin drivers to interface the remote experiment hardware; and 3) a client core based on a multi-tab user interface supporting text file management to exchange experiment scripts / status information, and a mini-browser for webcasting in distance learning scenarios, live image feedback from IP cameras located in the remote workbench, etc. Additional drivers and application-specific tabs can be added to the server / client cores, to suit the requirements of each application. Two remote workbenches for microcontroller and digital systems testing courses were developed, and are also presented in this document