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AbstractThe Experimental Pilot Plant for Tritium and Duterium Separation has been designed and built at the Rm. Valcea National Research and Development Institute for Cryogenics and Isotopic Technologies to separate deuterium and tritium from deuterated and tritiated water based on two combined processes: catalytic isotope exchange and cryogenic distillation. For this, additional experimental stands were developed for testing different components of the columns, such as the cold box, heat exchangers, condensers, and boilers. This paper presents the design of a new generation of fin condensers that avoids film condensation and allows the dropwise condensation mode. A small-scale cryogenic system equipped with a hydrogen liquefaction unit is presented as an alternative for condenser conductivity testing. The condenser is fixed on a hydrogen tank that is protected by a radiation shield and mounted inside a vacuum chamber. The proposed method is to continuously liquefy hydrogen using a two-stage Gifford McMahon 4K cycle cryocooler. A method for estimating the liquefaction rate was proposed and confirmed by the test results.

Abstract: The exergy of nuclear radiation is evaluated by using a simple quantum statistical thermodynamic approach. Only radiation particles with non-zero rest mass are considered (i.e. protons, neutrons, alpha and beta particles). The exergy and the exergy flux involve efficiency-like factors affecting the internal energy and the energy flux, respectively. These factors are generally different from both the usual Carnot factor and the Petela-Landsberg-Press factor that appears in the exergy of blackbody radiation. The efficiency-like factors are higher in the case of charged rather than neutral particles and in the case of enclosed rather than free radiation. The results are compared with those obtained previously by using a classical thermodynamic theory.

The logit-weighted reduced mixture of experts model (LRMoE) is a flexible yet analytically tractable non-linear regression model. Though it has shown usefulness in modeling insurance loss frequencies and severities, model calibration becomes challenging when censored and truncated data are involved, which is common in actuarial practice. In this article, we present an extended expectation–conditional maximization (ECM) algorithm that efficiently fits the LRMoE to random censored and random truncated regression data. The effectiveness of the proposed algorithm is empirically examined through a simulation study. Using real automobile insurance data sets, the usefulness and importance of the proposed algorithm are demonstrated through two actuarial applications: individual claim reserving and deductible ratemaking.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.technovation.2008.07.005 Byline: Mariela Badescu (a), Concepcion Garces-Ayerbe (b) Keywords: Information technologies; Labour productivity; Spanish firms; Panel data methodology; Firm-specific effects; Period-specific effects Abstract: In this article, we propose to analyse the impact of investments in information technologies (ITs) on the productivity of Spanish firms. Using a representative panel of 341 medium-sized and large firms, we used a Cobb-Douglas function to measure the contribution of IT capital to labour productivity. The results obtained reveal that the sensitivity of labour productivity to changes in technological capital intensity is positive and significant when firm-specific effects are corrected. However, this relationship is not significant when not only firm-specific, but also period-specific effects, are corrected. The conclusion obtained from these results shows that, although the firms in the samples experienced some improvement in labour productivity in the considered period, this improvement was not significantly derived from IT investment. Author Affiliation: (a) Department of Economics and Communications, University of Timisoara, Pestalozzi, No. 16, 300 115 Timisoara, Romania (b) Department of Economics and Business Management, University of Zaragoza, Gran Via, No. 2, 50 005 Zaragoza, Spain

The physiological characteristics considered here are the weight carried by the user and the walking frequency. Since the input force is low frequency, the mechanical response of the piezoelectric stack may be neglected and a model based on a first order differential equation is developed. Direct optimal control techniques are used. Three objective functions are defined in case of the resistive load and one objective function is considered for the capacitive load. General conclusions: (1) the maximum harvesting performance is obtained when the control parameters have a bang-bang-type time evolution or are constant; (2) sizing the load is strongly constrained by the physiological characteristics of the backpack user. Specific result for resistive loads: (3) the amount of dissipated energy increases by increasing the walking frequency, for both controlled and un-controlled operation. Specific results for capacitive loads: (4) the optimal capacitance is constant in time and equals the smallest allowed value; (5) the amount of energy stored in a capacitor when fully charged depends on the average weight carried by the backpack user; (6) the stored energy increases by increasing the walking frequency.

AbstractThis paper introduces a new juliapackage, LRMoE, a statistical software tailor-made for actuarial applications, which allows actuarial researchers and practitioners to model and analyse insurance loss frequencies and severities using the Logit-weighted Reduced Mixture-of-Experts (LRMoE) model. LRMoE offers several new distinctive features which are motivated by various actuarial applications and mostly cannot be achieved using existing packages for mixture models. Key features include a wider coverage on frequency and severity distributions and their zero inflation, the flexibility to vary classes of distributions across components, parameter estimation under data censoring and truncation and a collection of insurance ratemaking and reserving functions. The package also provides several model evaluation and visualisation functions to help users easily analyse the performance of the fitted model and interpret the model in insurance contexts.

Insurance loss severity data often exhibit heavy-tailed behavior, complex distributional characteristics such as multimodality, and peculiar links between policyholders’ risk profiles and claim amounts. To capture these features, we propose a transformed Gamma logit-weighted mixture of experts (TG-LRMoE) model for severity regression. The model possesses several desirable properties. The TG-LRMoE satisfies the denseness property that warrants its full versatility in capturing any distribution and regression structures. It may effectively extrapolate a wide range of tail behavior. The model is also identifiable, which further ensures its suitability for statistical inference. To make the TG-LRMoE computationally tractable, an expectation conditional maximization (ECM) algorithm with parameter penalization is developed for efficient and robust parameter estimation. The proposed model is applied to fit the severity and reporting delay components of a European automobile insurance dataset. In addition to obtaining excellent goodness of fit, the proposed model is shown to be useful and crucial for adequate prediction of incurred but not reported (IBNR) reserves through out-of-sample testing.

Background. Shared decision making (SDM) is becoming more and more important for the patient-physician interaction. There has not been a study in Romania evaluating patients’ point of view in the SDM process yet. Therefore, the present study aims to evaluate the psychometric parameters of the translated Romanian version of SDM-Q-9.

Results from retrospective studies suggest that use of neuromuscular blocking agents during general anaesthesia might be linked to postoperative pulmonary complications. We therefore aimed to assess whether the use of neuromuscular blocking agents is associated with postoperative pulmonary complications.

The last decade of the 20th century provided a unique opportunity for Central and Eastern Europe to transition from a command economy and dictatorship to a market economy and democracy. [...]

A new formalism is used to evaluate the amount of available work transported by the solar energy flux. The formalism is based on the concept of statistically deformed blackbody radiation. It covers cases when the concept of exergy is not fully relevant. An indicator called work content factor κU+is used to quantify the proportion of available work in the energy flux. Several previous results are particular cases of this general approach. In case of primary work extractors made of materials without energy bandgap (such as metals), the work content factor decreases by increasing the temperature Tcof the primary work extractor. At large values of Tcand smaller values of the solar radiation concentration work cannot be generated in some cases. Primary work extractors based on materials with bandgap energy (such as solar cells) may provide work when blackbody or statistically deformed blackbody solar radiation is unconcentrated. The work content factor of the solar energy flux is higher in the latter case.

This paper presents models/strategies for optimum performance of solar collector in closed loop systems. These models aim to maximize the obtained energy by thermal conversion of solar energy. The mass flow rate of the fluid from the primary circuit of the system is the control parameter. The semi empirical models and optimal control methods are in brief presented. The volume of the storage tank is important and the ratio Vs/Acbetween this volume and area of the collectors is a key factor in appropriate sizing of the DHW system. Therefore, the paper establishes a relationship between this ratio and the mass flow rate of the fluid in the collector This paper also analyses the variation of the energetic performance (useful heat flux transferred to the storage tank, heat flux transferred to the water, water temperature in the storage tank) with the volume of the storage tank. Analysis was performed on an extensive set of meteorological data from Timisoara, Romania, with instantaneous data (measured at 15 seconds) for summer days, from July 2009, with different relative sunshine values, σ. Important differences have been observed between days with different stability levels - days more or less stable.

ABSTRACTNational and international adaptive thermal comfort (ATC) standards gain now wider acceptance. These standards propose adaptive comfort equations derived from specific databases. New ATC equations are developed worldwide, under different latitudes and climates. A field survey has been performed in 2013–2014 in six naturally ventilated buildings located in Bucharest (Romania, Köppen type D - temperate continental climate). Comfort parameters were measured and comfort questionnaires were distributed. Using the theory of ASHRAE 55 Standard an ATC equation specific to Romanian climate has been proposed for the first time. Also, the 80% and 90% acceptability bands were determined in this situation. The new ATC equation has been compared with other ATC equations found in literature for similar climates. New thermal comfort investigations have been performed one year later after the first survey, new comfort investigations were performed. The ATC equation has been checked and good agreement has been found.

In this paper, the possibility to accurately reconstruct the energy and direction of high-energy cosmic rays using a network of 192 radio detectors, assembled on an area of about 20 km2, is investigated. Measurements are influenced by the properties of the detecting equipment; therefore, its behavior and limiting effects are discussed. The responses of the detection chain to radio pulses generated by cosmic particles with different characteristics are analyzed, and it is concluded that individual stations can serve as first estimators for the types of cosmic particles. The proposed radio network can resolve events (with energies higher than 1018 eV) coming from N-NW direction, with zenith angles higher than 44°. Simulations have also shown that lighter particles that interact closer to the Earth are more likely to be detected.

Therapies targeting epidermal growth factor receptor (EGFR) have variable and unpredictable responses in breast cancer. Screening triple-negative breast cancer (TNBC) patient-derived xenografts (PDXs), we identify a subset responsive to EGFR inhibition by gefitinib, which displays heterogeneous expression of wild-type EGFR. Deep single-cell RNA sequencing of 3,500 cells from an exceptional responder identified subpopulations displaying distinct biological features, where elevated EGFR expression was significantly enriched in a mesenchymal/stem-like cellular cluster. Sorted EGFRhisubpopulations exhibited enhanced stem-like features, including ALDH activity, sphere-forming efficiency, and tumorigenic and metastatic potential. EGFRhicells gave rise to EGFRhiand EGFRlocells in primary and metastatic tumors, demonstrating an EGFR-dependent expansion and hierarchical state transition. Similar tumorigenic EGFRhisubpopulations were identified in independent PDXs, where heterogeneous EGFR expression correlated with gefitinib sensitivity. This provides new understanding for an EGFR-dependent hierarchy in TNBC and for patient stratification for therapeutic intervention.

ABSTRACTThe Solar Power Satellite (SPS) is a renewable energy technology potentially capable of meeting the projected worldwide energy demand for future generations. Some general aspects of SPSs are discussed in this paper. It was calculated that a power output of 97.24 MW (almost double the power produced by a typical natural gas plant) could be generated using a theoretical system with solar photovoltaics with a total optimised dimension of 0.18 km2. Among the potential problems discussed are the possible effect of microwaves on living organisms and the high capital costs involved in building and launching the satellite into a suitable orbit.

The objective of the work is to present some researches regarding the virtual modelling of external medical devices with wire insertion. Ankle foot orthoses are used to correct and prevent different disfunctions of the human body and also in athlets recovery. The research is motivate by the problems appeared using this medical devices: durability issues, patient confort, manufacturing costs, lightweight, flexible access to shoes, inexpensive, readily available. These issues depends of the wey design, manufacturing technology, materials used, patient behavior, skills manufacturer. Wire insertion in polypropylene is a new approach of orthoses materials.

Context.To investigate the link between the International Celestial Reference Frame (ICRF) and its optical Hipparcos-based representation on the northern hemisphere.

Two of the key purposes of future NASA’s solar system exploration of planetary bodies are the search for potentially preserved bio-signatures and for habitable regions. To address these objectives, a biologically inspired wireline deep rotary-percussive drill, called Auto-Gopher, has been developed. This drill employs a piezoelectric actuated percussive mechanism for generating impulsive stresses and breaking formations, and an electric motor to rotate the bit to break material and remove the cuttings. Initially, the drill was designed as percussive mechanism for sampling ice and was demonstrated in 2005 at Lake Vida, Antarctica, reaching about 2 m depth. The lessons learned suggested there is a need to augment the percussive action with bit rotation in order to maximize the penetration rate. The first generation implementation of the rotary augmentation was focused on the demonstration of this capability. In 2012, during the 3-day field test, the drill reached a 3-meter deep in gypsum. A separate mechanism was used to break and remove the cores. The average drilling power consumption was in the range of 100-150 Watts, while the rate of penetration was approximately 2.4 m/hr. Currently under development is the second-generation drill, called Auto-Gopher 2. The drill will be fully autonomous. In this paper, the capabilities that are being integrated into the Auto-Gopher-2 are described and discussed.

This paper presents the experimental and theoretical assessment of the thermal behaviour of a roll-bond evaporator in a small-scale household refrigerator using the refrigerant R600a as a working fluid. The experimental data were compared with a general correlation employed to evaluate the heat transfer convection (HTC) and radiation of vertical and horizontal plates of the roll-bond evaporator. The evaporator is placed at the top side of the refrigerator. To provide the right boundary state of the evaporator, the refrigerated chamber was taken into consideration. The acquisition data system and experimental setup are described. The local radiation and convective heat transfer coefficient (CHTC) were determined for variation in heating power. In the case of small refrigerated spaces, the heat transfer through radiation cannot be neglected. The CHTC of internal vertical walls is lower than that of exterior walls. The refrigerator is equipped with an electric static heater to provide the corresponding cooling capacity. The steady-state cooling capacity predictions based on refrigerant enthalpy differences and heat source energy equation balancing were 9.66% and 0.88 % higher than manufacturing data. The results achieved a good agreement when the theoretical and experimental data are compared.

The first Passive House (PH) was built in 1990/1991 in Darmstadt-Kranischstein (Germany). It was the first real-size implementation of a concept proposed by Wolfgang Feist. Since then, several empirical design solutions have been developed by the Passive House Institute (PHI) of Darmstadt. This paper deals with the feasibility of the PH concept in Southern Hemisphere. The paper compares general climate conditions for 13 European localities and 38 localities in South America, South Africa, mainland Australia, Tasmania, and New Zealand. Further analysis is performed by estimating the energy performance of a prototype passive building when located in any of these localities. The prototype passive building is AMVIC PH built in 2008 in Bragadiru (Romania). The energy performance is evaluated by using the Passive House Planning Package (PHPP) developed by PHI. Passive buildings located in Tasmanian and South American localities at latitudes higher than 53° have a higher heating demand than European localities at similar latitudes. New Zealand and South American localities at latitudes lower than 53° generally have lower heating demand than European localities at the same latitude. The cooling demand is generally smaller in Southern Hemisphere than in Northern Hemisphere. Passive buildings placed in Tasmania, New Zealand, and South America do not require cooling while those located in South Africa and mainland Australia require a reduced amount of cooling.

The conjugation of monomethyl auristatin E (MMAE) to trastuzumab using a reduction bis-alkylation approach that is capable of rebridging reduced (native) antibody interchain disulfide bonds has been previously shown to produce a homogeneous and stable conjugate with a drug-to-antibody ratio (DAR) of 4 as the major product. Here, we further investigate the potency of the DAR 4 conjugates prepared by bis-alkylation by comparing to lower drug loaded variants to maleimide linker based conjugates possessing typical mixed DAR profiles. Serum stability, HER2 receptor binding, internalization, in vitro potency, and in vivo efficacy were all evaluated. Greater stability compared with maleimide conjugation was observed with no significant decrease in receptor/FcRn binding. A clear dose–response was obtained based on drug loading (DAR) with the DAR 4 conjugate showing the highest potency in vitro and a much higher efficacy in vivo compared with the lower DAR conjugates. Finally, the DAR 4 conjugate demonstrated superior efficacy compared to trastuzumab–DM1 (T-DM1, Kadcyla), as evaluated in a low HER2 expressing JIMT-1 xenograft model.

We develop here a microscopical model of quasi-regular impurity distribution driven by the CDW appropriate for highly mobile impurities or materials with fictitious CDW transition temperature. Thermal hysteresis effects at the CDW transition reported in the quasi-1D materials NbSe3and Ta2NiSe7, could be interpreted in the framework of the present model. Possible connections with other (alloy, heavy-fermion) systems are also suggested.

This paper considers a model consisting of : (i) a source of partially polarized black-body radiation (the pump), (ii) a thermally radiative or non-radiative ambient sink and (iii) two energy converters. The first converter (RH) transforms the energy of the black-body radiation into heat, while the second one (HW) (which has a non-zero entropy generation rate) uses that heat to produce work. The entropy-generation rates in the two converters are non-negative only when some conditions are satisfied, which relate the coefficients of polarization, the three temperatures (of the pump, ambient and converter RH) and the solid angle subtended by the pump. The range of validity of some upper bounds proposed in literature for the conversion efficiency of the radiation energy into work is also determined. Thermal equilibrium imposes some relations between the polarization of the radiation and the solid angle subtended by the pump. The maximum efficiency is studied for the situation when the HW converter follows a regenerative cycle.

The influence of the atmospheric state on the extinction of direct solar radiation has been studied by using a four layer atmospheric model. Simple analytical formulae are established for the spectral optical depths of permanent gases and water vapour. These formulae use the ground level values of air pressure, temperature and relative huniidity. An additional parameter, related to the vertical distribution of the hunmidity content, is used for a better estimation of the water vapour optical depth. Good agreement between theory and measurements is found. The paper shows the dependence of the atmospheric spectral transmittance on the above mentioned parameters.

This paper presents an experimental study carried out on the properties of Ti depositions, obtained through thermal spraying in electric arc - thermally activated. The spraying process is a combination between the classical process of thermal spraying and the spraying process in flame. Finite elements analysis of the thermal spraying process in electric arc, allowed the estimated determination of the temperature variations of the jet drive, of the amount of gaseous fuel and also of the optimum spraying distance. The investigations, carried out through the performing electron microscopy analyses (SEM), X-ray diffraction, by determining the porosity and the adhesion of the Ti deposition, allowed the highlight fact that through an optimum choosing of the entrainment jet temperature, are producing dense Ti deposits, characterized by high adhesion (16%). In addition, the deposit porosity -required for integration of the biocompatible materials, can be controlled by the optimal choosing of the spray distance.