Thermomechanical behaviour of silty sandy clays: An experimental and numerical investigation

This paper is devoted to the experimental and numerical investigation of the effect of temperature on the volumetric behaviour of silty sandy clay. A temperature-controlled oedometer is developed to study thermally induced volume change. In this system, an electrical ring heater is placed around the conventional oedometer cell, which accommodates the sample. A very low temperature increase rate was achieved by the thermal controller unit to ensure reasonable saturation durations. The interpretation of the test is assisted by the performance of a numerical analysis based on a coupled formulation incorporating the relevant THM phenomena. Heating and cooling at constant isotropic stress show that the thermal volumetric behaviour of clay samples depends on various factors, such as recent stress history prior to the heating and cooling test. The performance and analysis of the thermal consolidation tests have significantly enhanced the understanding of the thermal volumetric behaviour of tested clay and have proved the capability of the numerical formulation to provide adequate modelling capacity

Nowotwory neuroendokrynne żołądka i dwunastnicy z uwzględnieniem gastrinoma — zasady postępowania (rekomendowane przez Polską Sieć Guzów Neuroendokrynnych)

This paper presents the updated Polish Neuroendocrine Tumour Network expert panel recommendations on the management of neuroendocrine neoplasms (NENs) of the stomach and duodenum, including gastrinoma. The recommendations discuss the epidemiology, pathogenesis and clinical presentation of these tumours as well as their diagnosis, including biochemical, histopathological and localisation diagnosis. The principles of treatment are discussed, including endoscopic, surgical, pharmacological and radionuclide treatment. Finally, recommendations on patient monitoring are given. (Endokrynol Pol 2013; 64 (6): 444–458)W niniejszej pracy przedstawiono uaktualnione zalecenia grupy ekspertów Polskiej Sieci Guzów Neuroendokrynnych dotyczące zasad postępowania w nowotworach neuroendokrynnych żołądka i dwunastnicy z uwzględnieniem gastrinoma. Omówiono epidemiologię, patogenezę i obraz kliniczny tych nowotworów. Przedstawiono zalecenia dotyczące zasad postępowania diagnostycznego, z uwzględnieniem diagnostyki biochemicznej, histopatologicznej oraz lokalizacyjnej. Uwzględniono także zasady postępowania terapeutycznego, w tym leczenie endoskopowe i chirurgiczne, oraz omówiono możliwości leczenia farmakologicznego i radioizotopowego. Przedstawiono także zalecenia odnośnie monitorowania chorych z NEN żołądka, dwunastnicy z uwzględnieniem gastrinoma. (Endokrynol Pol 2013; 64 (6): 444–458

Colorectal neuroendocrine neoplasms — management guidelines (recommended by the Polish Network of Neuroendocrine Tumours)

Nowotwory neuroendokrynne (NENs) jelita grubego stanowią 20% wszystkich nowotworów neuroendokrynnych. Najczęstszą ich lokalizacją jest odbytnica. Nowotwory neuroendokrynne jelita grubego są wykrywane coraz częściej i liczba ta będzie wzrastać z uwagi na powszechność wykonywania kolonoskopii, w tym badań przesiewowych oraz usuwanie wykrytych zmian. W pracy przedstawiono aktualne zalecenia dotyczące diagnostyki i terapii NEN jelita grubego, z uwzględnieniem diagnostyki biochemicznej, patomorfologicznej, nowych technik obrazowania oraz leczenia endoskopowego, chirurgicznego, farmakologicznego i radioizotopowego. Omówiono także epidemiologię, charakterystykę kliniczną i monitorowanie leczenia. (Endokrynol Pol 2013; 64 (6): 494–504)Neuroendocrine neoplasms of the large intestine account for 20% of all neuroendocrine neoplasms (NENs) and are most commonly found in the rectum. The rate of detection of colorectal NENs is increasing, and this tendency will continue due to the widespread use of colonoscopy as a screening tool and the removal of all diagnosed lesions. This paper provides updated guidelines for the management of patients with colorectal NENs. Recent data on epidemiology, clinical characteristics, biochemical, and pathomorphological diagnosis as well as useful imaging techniques are presented. We look in detail at novel methods of treatment including endoscopic and surgical management, pharmacological and radioisotope therapy. We summarise monitoring of the treatment. (Endokrynol Pol 2013; 64 (6): 494–504

Quel rôle faut-il réserver aux structures sociales dans l’explication ?

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Performance Model for MRC Receivers with Adaptive Modulation and Coding in Rayleigh Fading Correlated Channels with Imperfect CSIT Performance Model for MRC Receivers with Adaptive Modulation and Coding in Rayleigh Fading Correlated Channels with Imperfec

Abstract This paper presents a performance model of the packet reception process in a wireless link with one antenna transmitter and a multiple-antenna maximum-ratio combining (MRC) receiver. The objective is to address the performance evaluation of multiple antenna systems enabled with adaptive modulation and coding (AMC). Two main assumptions are used: 1) Rayleigh fading correlated channels, and 2) imperfect (outdated) channel state information at the transmitter side (CSIT). The results presented here suggest that spatial correlation not always affects the performance of the MRC receiver: at low signal-to-noise ratio (SNR), correlation can improve performance rather than degrading it. By contrast, at high SNR, correlation is found to always degrade performance. At high SNR, correlation tends to worse the degrading effects of imperfect CSIT, particularly when the number of antennas increases. Imperfect CSIT causes errors in the assignment of MCSs, thus reducing throughput performance. These errors become more evident at high SNR, particularly when the values of branch correlation and the number of antennas increase. Abstract-This paper presents a performance model of the reception process in a wireless link with one antenna transmitter and a multiple-antenna maximum-ratio combining (MRC) receiver. The objective is to address the performance evaluation of multiple antenna systems enabled with adaptive modulation and coding (AMC). Two main assumptions are used: 1) Rayleigh fading correlated channels, and 2) imperfect (outdated) channel state information at the transmitter side (CSIT). The results presented here suggest that spatial correlation not always affects the performance of the MRC receiver: at low signal-to-noise ratio (SNR), correlation can improve performance rather than degrading it. By contrast, at high SNR, correlation is found to always degrade performance. At high SNR, correlation tends to worse the degrading effects of imperfect CSIT, particularly when the number of antennas increases. Imperfect CSIT causes errors in the assignment of modulation and coding schemes (MCSs), thus reducing throughput performance. These errors become more evident at high SNR, particularly when the values of branch correlation and the number of antennas increase

New topology for voltage balancing in railway substations

This paper deals with a new technique of voltage unbalance compensation for single phase railway substations. Using the concept of Chopper Controlled Impedance, the authors study the feasibility of an active Steinmetz circuit based on AC choppers. The low power losses in semiconductor devices make the proposed topology an interesting alternative to classical solution like VSI based. Design criteria are presented using information got from measurements carried out in a substation of the French Railways. Finally, the study is validated by means of simulations and experimental results carried out on a 1.5 kVA prototyp

Study of the Reliability of Statistical Timing Analysis for Real-Time Systems Dorin Maxim Study of the Reliability of Statistical Timing Analysis for Study of the Reliability of Statistical Timing Analysis for Real-Time Systems Study of the Reliability of

Abstract Probabilistic and statistical temporal analyses have been developedas a means of determining the worst-case execution and responsetimes of real-time software for decades. A number of such methodshave been proposed in the literature, of which the majority claim tobe able to provide worst-case timing scenarios with respect to agiven likelihood of a certain value being exceeded. Further, suchclaims are based on either some estimates associated with a probability,or probability distributions with a certain level of confidence.However, the validity of the claims are very much dependent on anumber of factors, such as the achieved samples and the adopteddistributions for analysis.In this paper, we investigate whether the claims made are in facttrue as well as the establishing an understanding of the factors thataffect the validity of these claims. The results are of importancefor two reasons: to allow researchers to examine whether there areimportant issues that mean their techniques need to be refined; andso that practitioners, including industrialists who are currently usingcommercial timing analysis tools based on these types of techniques,understand how the techniques should be used to ensure theresults are fit for their purposes. Study of the Reliability of Statistical Timing Analysis for Real-Time Systems ABSTRACT Probabilistic and statistical temporal analyses have been developed as a means of determining the worst-case execution and response times of real-time software for decades. A number of such methods have been proposed in the literature, of which the majority claim to be able to provide worst-case timing scenarios with respect to a given likelihood of a certain value being exceeded. Further, such claims are based on either some estimates associated with a probability, or probability distributions with a certain level of confidence. However, the validity of the claims are very much dependent on a number of factors, such as the achieved samples and the adopted distributions for analysis. This paper is the first one that puts side by side existing state of the art statistical and probabilistic analysis techniques, using the probabilistic analysis as the ground truth in order to asses the applicability and performance of the statistical technique. The evaluation clearly shows that for the experiments performed the approach can identify clear differences between a range of techniques and that these differences can be considered valid based on the trends expected from the academic theory