Моделирование энергопотребления зданий: оценка статической и динамической моделей

The aim of the present paper is to show recent results obtained in modeling the building system, presenting a review on the common numerical models used to estimate the energy consumptions. In particular, both steady-state and dynamic models are investigated by analyzing their main assumptions, limitations and fields of usage. As a matter of fact, the most common models are based on steady state approaches, but new technologies and the need to implement innovative regulation criteria for heating and cooling systems by performing detailed coupled studies on the building and heating/cooling systems, push towards the use of dynamic tools with low computational costs. Therefore, the use of dynamic models is often suggested, especially when different building configurations are investigated (as e. g. in the design stage or for a renovation perspective). Starting from this point, sensitive analyses on the installation of a proper insulation in the building envelope is then presented.Цель данной работы — показать последние результаты, полученные при моделировании системы здания, с описанием общих численных моделей, используемых для оценки энергопотребления. В частности на статических и динамических моделях исследованы основные допущения, ограничения и область использования путем их анализа. Собственно говоря, наиболее распространенные модели основаны на установившихся подходах, но новые технологии и необходимость внедрения для систем отопления и холодоснабжения инновационных критериев регулирования с использованием подробного анализа здания и систем отопления/охлаждения, подталкивают к использованию динамических инструментов с низкими вычислительными затратами. Таким образом, часто целесообразно использование динамических моделей, особенно когда существуют разные конфигурации здания (как, например, в стадии проектирования или для перспективной реконструкции). В статье представлен анализ установки правильного утеплителя в ограждающих конструкциях

The HST Survey of BL Lacertae Objects. I. Surface Brightness Profiles, Magnitudes, and Radii of Host Galaxies

We report on a large HST imaging survey of BL Lac objects, at spatial resolution ~10 times better than previous ground-based surveys. We focus on data reduction and analysis, describing the procedures used to model the host galaxy surface brightness radial profiles. A total of 69 host galaxies were resolved out of 110 objects observed, including almost all sources at z < 0.5. We classify them morphologically by fitting with either an exponential disk or a de~Vaucouleurs profile; when one fit is preferred over the other, in 58 of 69 cases, it is invariably the elliptical morphology. This is a very strong result given the large number of BL Lac objects, the unprecedented spatial resolution, and the homogeneity of the data set. With the present reclassification of the host galaxy of 1418+546 as an elliptical, there remain no undisputed examples of a disk galaxy hosting a BL Lac nucleus. This implies that, at 99% confidence, fewer than 7% of BL Lacs can be in disk galaxies. The apparent magnitude of the host galaxies varies with distance as expected if the absolute magnitudes are approximately the same, with a spread of +-1 mag, out to redshift z < 0.5. At larger redshifts, only 6 of 23 BL Lacs are resolved so the present data do not constrain possible luminosity evolution of the host galaxies. The collective Hubble diagram for BL Lac host galaxies and radio galaxies strongly supports their unification.Comment: Accepted for publication on ApJS. 43 pages. 10 figures. Figure 1 can also be downloaded from http://icarus.stsci.edu/~scarpa/tmp/hst_figure1.ta

Mucopolysaccharidosis type II: preliminary data on glycosaminoglycan levels and structure in mice at baseline and after 6 weeks treatment with ERT

Mucopolysaccharidosis type II is a lysosomal storage disease due to the deficit of the enzyme iduronate 2-sulfatase (IDS) and to the consequent accumulation of heparan- (HS) and dermatan-sulfate (DS), with multi-organ involvement. In this study we characterized glycosaminoglycan (GAG) levels and structure in the brain and liver of the Ids knock-out mouse model, at 12 weeks of age and after 6 weeks treatment with human IDS (hIDS) enzyme, by using the capillary electrophoresis-laser induced fluorescence (CE-LIF) technique. As expected, Ids-ko mice showed a heavy accumulation of HS, about 15 times higher than wild-type (wt) in the brain and up to 240 times in the liver. The overall HS charge density rose by 1.5 times only in the liver, but the sulfation pattern changed in both organs. We also observed an increased chondroitin-sulfate (CS)+DS levels of about 2 times in the brain and 5 times in the liver, but an increased CS/DS ratio of about 22 times only in the liver. On the contrary, the hyaluronic acid (HA) levels did not change in both organs. We also conducted the same analysis in Ids-ko mice treated with 1 mg/kg of hIDS, once a week. As expected, we observed in the liver a huge reduction of HS (20 times vs untreated mice) and also of CS+DS and CS/DS. Instead, we did not observe a reduction of the different GAGs in the brain, confirming the enzyme inability to cross BBB. In this district a slight increase of CS/DS ratio, CS+DS and HA levels, and an about 40% increase of HS level, vs untreated ko mice, was observed. On the opposite, the overall HS charge density is decreased 2.5X vs untreated ko and wt mice. This preliminary data underline how by using a more sensitive technique of analysis, a clear separation of the GAGs pattern between wt and Ids-ko mice can be observed. This results particularly important for the brain, where application of common biochemical techniques detects very low GAG levels in both animal types, thus limiting the use of GAG analysis as possible biomarker of therapeutic efficacy in the brain district. The application of CE-LIF analysis is therefore proposed for a detailed evaluation of GAG pattern for potential monitoring of therapeutic efficacy

The nature of optical and near-infrared variability of BL Lacertae

Since 1997, BL Lacertae has undergone a phase of high optical activity, with the occurrence of several prominent outbursts. Starting from 1999, the Whole Earth Blazar Telescope (WEBT) consortium has organized various multifrequency campaigns on this blazar, collecting tens of thousands of data points. One of the main issues in the analysis of this huge dataset has been the study of colour variability. The massive amount of optical and near-infrared data collected during the campaigns enables us to perform a deep analysis of multiband data, with the aim of understanding the flux variability mechanisms. We use a new approach for the analysis of these data, focusing on the source spectral evolution. We show that the overall behaviour of the BL Lacertae light and colour curves can be explained in terms of changing viewing angle of a moving, discrete emitting region, which causes variable Doppler boosting of the corresponding radiation. A fractal helical structure is suggested to be at the origin of the different time scales of variability.Comment: 6 pages, 8 figures, accepted by A&

Wearable piezoelectric mass sensor based on pH sensitive hydrogels for sweat pH monitoring

Colorimetric and electrochemical (bio)sensors are commonly employed in wearable platforms for sweat monitoring; nevertheless, they suffer from low stability of the sensitive element. In contrast, mass-(bio)sensors are commonly used for analyte detection at laboratory level only, due to their rigidity. To overcome these limitations, a flexible mass-(bio)sensor for sweat pH sensing is proposed. The device exploits the flexibility of piezoelectric AlN membranes fabricated on a polyimide substrate combined to the sensitive properties of a pH responsive hydrogel based on PEG-DA/CEA molecules. A resonant frequency shift is recorded due to the hydrogel swelling/shrinking at several pH. Our device shows a responsivity of about 12 kHz/pH unit when measured in artificial sweat formulation in the pH range 3-8. To the best of our knowledge, this is the first time that hydrogel mass variations are sensed by a flexible resonator, fostering the development of a new class of compliant and wearable devices

Chandra and HST observations of gamma-ray blazars: comparing jet emission at small and large scales

We present new Chandra and HST data for four gamma-ray blazars selected on the basis of radio morphology with the aim of revealing X-ray and optical emission from their jets at large scales. All the sources have been detected. Spectral Energy Distributions of the large scale jets are obtained as well as new X-ray spectra for the blazar cores. Modeling for each object the core (sub-pc scale) and large-scale (>100 kpc) jet SEDs, we derive the properties of the same jet at the two scales. The comparison of speeds and powers at different scales supports a simple scenario for the dynamics and propagation of high power relativistic jets.Comment: Accepted for publication in Ap

A Viewing Angle - Kinetic Luminosity Unification Scheme For BL Lacertae Objects

We propose a unified classification for BL Lac objects (BLs), focusing on the synchrotron peak frequency of the spectral energy distribution. The unification scheme is based on the angle Theta that describes the orientation of the relativistic jet and on the electron kinetic luminosity Lambda of the jet. We assume that Lambda scales with the size of the jet r in a self-similar fashion (Lambda propto r^2), as supported by observational data. The jets are self-similar in geometry and have the same pressure and median magnetic field at the inlet, independent of size. The self-similarity is broken for the highest energy electrons, which radiate mainly at high frequencies, since for large sources they suffer more severe radiative energy losses over a given fraction of the jet length. We calculate the optically thin synchrotron spectrum using an accelerating inner jet model based on simple relativistic gas dynamics and show that it can fit the observed infrared to X-ray spectrum of PKS 2155--304. We couple the accelerating jet model to the unification scheme and compare the results to complete samples of BLs. The negative apparent evolution of X-ray selected BLs is explained as a result of positive evolution of the jet electron kinetic luminosity $\Lambda_{kin}$. We review observational arguments in favor of the existence of scaled-down accretion disks and broad emission-line regions in BLs. The proposed unification scheme can explain the lack of observed broad emission lines in X-ray selected BLs, as well as the existence of those lines preferentially in luminous radio-selected BLs. Finally, we review observational arguments that suggest the extension of this unification scheme to all blazars.Comment: 32 pages, 8 figures, to be published in the ApJ (Oct 20, 1998

Applied investigation of person-specific and context-specific factors on postoperative recovery and clinical outcomes of patients undergoing gastrointestinal cancer surgery: multicentre European study

INTRODUCTION: Cancer treatments have greatly advanced over the past two decades causing survival improvements and reduced complications from cancer surgery. However, the cancer diagnosis and the effects of treatment modalities pose a major risk to patients' psychological well-being. Given current interest and emerging evidence about the importance of psychological and social factors on cancer survival and coping with cancer treatments, this study will build and expand research in order to identify key modifiable psychosocial variables that contribute to better physical and mental health following gastrointestinal cancer (GIC) surgery. OBJECTIVES: To elucidate the incidence of postoperative psychiatric morbidity within 6 months following GIC surgery. To identify key measurable modifiable preoperative psychological factors that can significantly affect postoperative psychiatric morbidity in patients undergoing surgery for GIC. To clarify the changes seen in a patient's psychological well-being during their treatment pathway for GIC. METHODS AND ANALYSIS: This multicentre study has an observational longitudinal study design. In total, 1000 patients will be screened with a multicomponent psychological questionnaire at four different time points: at diagnosis, preoperatively, 1 and 6 months after surgery. Data from this questionnaire will be linked to postoperative complications including psychiatric morbidity, length of hospital stay and recovery to normal activity. ETHICS AND DISSEMINATION: NHS Health Research Authority approval was gained on (REC reference 15.LO/1847) for the completion of this study. Multiple platforms will be used for the dissemination of the research data, including international clinical and patient group presentations and publication of research outputs in a high impact clinical journal