Analysis and Application of Advanced Control Strategies to a Heating Element Nonlinear Model

open4siSustainable control has begun to stimulate research and development in a wide range of industrial communities particularly for systems that demand a high degree of reliability and availability (sustainability) and at the same time characterised by expensive and/or safety critical maintenance work. For heating systems such as HVAC plants, clear conflict exists between ensuring a high degree of availability and reducing costly maintenance times. HVAC systems have highly non-linear dynamics and a stochastic and uncontrollable driving force as input in the form of intake air speed, presenting an interesting challenge for modern control methods. Suitable control methods can provide sustainable maximisation of energy conversion efficiency over wider than normally expected air speeds and temperatures, whilst also giving a degree of “tolerance” to certain faults, providing an important impact on maintenance scheduling, e.g. by capturing the effects of some system faults before they become serious.This paper presents the design of different control strategies applied to a heating element nonlinear model. The description of this heating element was obtained exploiting a data driven and physically meaningful nonlinear continuous time model, which represents a test bed used in passive air conditioning for sustainable housing applications. This model has low complexity while achieving high simulation performance. The physical meaningfulness of the model provides an enhanced insight into the performance and functionality of the system. In return, this information can be used during the system simulation and improved model based and data driven control designs for tight temperature regulation. The main purpose of this study is thus to give several examples of viable and practical designs of control schemes with application to this heating element model. Moreover, extensive simulations and Monte Carlo analysis are the tools for assessing experimentally the main features of the proposed control schemes, in the presence of modelling and measurement errors. These developed control methods are also compared in order to evaluate advantages and drawbacks of the considered solutions. Finally, the exploited simulation tools can serve to highlight the potential application of the proposed control strategies to real air conditioning systems.openTurhan, T.; Simani, S.; Zajic, I.; Gokcen Akkurt, G.Turhan, T.; Simani, Silvio; Zajic, I.; Gokcen Akkurt, G

Die Rolle des familiär erhöhten Faktor VIII bei Kindern mit einer ersten Entstehung venöser Thrombosen (vT)

Evaluiert wurde die Rolle des familiär erhöhten Faktor VIII bei Kindern mit einer ersten Entstehung venöser Thrombosen und ob eine mögliche Verbindung zum Auftreten vom postthrombotischen Syndrom oder rezidivierender vT vorhanden ist. FVIII:Ag-, FVIIIC- und von Willebrand Faktor Antigen- Spiegel wurden zusammen mit bekannten Thrombophilien nach dem akuten thrombotischen Ereignis bei 103 kaukasischen Kindern im Alter von 0-18 Jahren berechnet, die an einer ersten vT leiden. Die medianen Werte von FVIII:Ag und FVIII:C- Werte waren bei den Patienten im Vergleich zu der Kontrollgruppe erhöht . Der Vergleich von FVIII-Werten mit FVIII-Werten unterhalb des altersabhängigen cut-offs,zeigte eine signifikant erhöhte Odds Ratio und einen 95%igen Konfidenzintervall bei Kindern mit vT. Innerhalb von 12 Monaten trat bei 19 von 59 Kindern ein PTS auf, bei fünf Individuen persistierte diese bei den Nachuntersuchungen: PTS war signifikant mit der Ausdehnung der ersten Thrombosebelastung assoziiert

Ground truth deficiencies in software engineering: when codifying the past can be counterproductive

Many software engineering tools build and evaluate their models based on historical data to support development and process decisions. These models help us answer numerous interesting questions, but have their own caveats. In a real-life setting, the objective function of human decision-makers for a given task might be influenced by a whole host of factors that stem from their cognitive biases, subverting the ideal objective function required for an optimally functioning system. Relying on this data as ground truth may give rise to systems that end up automating software engineering decisions by mimicking past sub-optimal behaviour. We illustrate this phenomenon and suggest mitigation strategies to raise awareness

Taking Differences between Turkish and English Languages into account in Internal Representations

It is generally assumed that the representation of the meaning of sentences in a knowledge representation language does not depend of the natural language in which this meaning is initially expressed. We argue here that, despite the fact that the translation of a sentence from one language to another one is always possible, this rests mainly on the fact that the two languages are natural languages. Using online translations systems (e.g. Google, Yandex translators) make it clear that structural differences between languages gives rise to more or less faithful translations depending on the proximity of the implied languages and there is no doubt that effect of the differences between languages are more crucial if one of the language is a knowledge representation language. Our purpose is illustrated through numerous examples of sentences in Turkish and their translation in English, emphasizing differences between these languages which belong to two different natural language families. As knowledge representations languages we use the first order predicate logic (FOPP) and the conceptual graph (CG) language and its associated logical semantics. We show that important Turkish constructions like gerunds, action names and differences in focus lead to representations corresponding to the reification of verbal predicates and to favor CG as semantic network representation language, whereas English seems more suited to the traditional predicates centered representation schema. We conclude that this first study give rise toideas to be considered as new inspirations in the area of knowledge representation of linguistics data and its uses in natural language translation systems

Software defect prediction: do different classifiers find the same defects?

Open Access: This article is distributed under the terms of the Creative Commons Attribution 4.0 International License CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.During the last 10 years, hundreds of different defect prediction models have been published. The performance of the classifiers used in these models is reported to be similar with models rarely performing above the predictive performance ceiling of about 80% recall. We investigate the individual defects that four classifiers predict and analyse the level of prediction uncertainty produced by these classifiers. We perform a sensitivity analysis to compare the performance of Random Forest, Naïve Bayes, RPart and SVM classifiers when predicting defects in NASA, open source and commercial datasets. The defect predictions that each classifier makes is captured in a confusion matrix and the prediction uncertainty of each classifier is compared. Despite similar predictive performance values for these four classifiers, each detects different sets of defects. Some classifiers are more consistent in predicting defects than others. Our results confirm that a unique subset of defects can be detected by specific classifiers. However, while some classifiers are consistent in the predictions they make, other classifiers vary in their predictions. Given our results, we conclude that classifier ensembles with decision-making strategies not based on majority voting are likely to perform best in defect prediction.Peer reviewedFinal Published versio

Matrix metalloproteinase-9 in broncho-alveolar lavage fluid of patients with non-small cell lung cancer

Aim: To evaluate concentration of MMP-9 in blood plasma and broncho-alveolar lavage fluid (BALF) from patients with non-small cell lung cancer (NSCLC). Methods: Blood рlasma from 40 NSCLC patients and 40 healthy donors was collected and concentrations of blood plasma and BALF MMP-9 were measured using ELISA. Correlation between MMP-9 level and gender, histological type of tumor and stage of disease was analyzed. Results: Levels of blood plasma MMP-9 were significantly higher in NSCLC patients (p < 0.0001) then in control group, and were especially high in patients with stage IV of disease (stage I vs stage IV — p < 0.005, stage II vs stage IV — p < 0.01, stage III vs stage IV — p < 0.01). Also, stage IV of NSCLC was characterized by the highest level of BALF MMP-9 (stage I vs stage IV — p < 0.002, stage II vs stage IV p < 0.002, and stage III vs stage IV p < 0.007). Correlation between blood plasma and BALF MMP-9 levels and gender or histological type of tumor was insignificant. Conclusion: Our data revealed significant correlation between tumor stage and BALF and plasma MMP-9 levels in NSCLC patients.Цель: определить концентрацию матриксной металлопротеиназы 9 (ММП-9) в плазме крови и бронхо-альвеолярной жидкости (БАЖ) больных немелкоклеточным раком легкого (НМКРЛ). Методы: концентрацию ММП-9 в плазме крови и БАЖ больных НМКРЛ (n = 40) и здоровых доноров (n = 40) определяли иммуноферментным методом и анализировали корреляцию этих параметров с клиническими данными (полом больного, гистологическим типом опухоли, стадией заболевания). Результаты: содержание ММП-9 в плазме крови было значительно выше у больных НМКРЛ по сравнению с контрольной группой (p < 0,0001), особенно у больных с IV стадией заболевания. Стадия IV НМКРЛ также характеризовалась наиболее высоким уровнем ММП-9 в БАЖ. Корреляции между уровнем ММП-9 в плазме крови и БАЖ, полом больного и гистологическим типом опухоли не была выявлена. Выводы: существует статистически значимая корреляция между стадией развития НМКРЛ и содержанием ММП-9 в плазме крови и БАЖ больных

Negative Even Grade mKdV Hierarchy and its Soliton Solutions

In this paper we provide an algebraic construction for the negative even mKdV hierarchy which gives rise to time evolutions associated to even graded Lie algebraic structure. We propose a modification of the dressing method, in order to incorporate a non-trivial vacuum configuration and construct a deformed vertex operator for $\hat{sl}(2)$, that enable us to obtain explicit and systematic solutions for the whole negative even grade equations

Bullous pemphigoid associated with prostate adenocarcinoma

Bullous pemphigoid is a common autoimmune skin disease characterized by the presence of subepidermal blisters. It has been associated with underlying neoplasia in isolated reports. A 78-year-old man with generalized blisters was diagnosed as bullous pemphigoid on clinical, histopathological and direct immunofluorescence grounds. His free and total prostate specific antigen (PSA) levels were high and histopathological examination of a prostate specimen revealed prostate adenocarcinoma. We present this rare case to discuss the possible association between bullous pemphigoid and prostate adenocarcinoma