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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2006.10.004 Byline: Mohamed Hamdouni, Francois Soumis, Guy Desaulniers Keywords: Bus parking and dispatching; Stochastic arrival times; Integer programming modeling; Simulation Abstract: Given buses of different types arriving at a depot during the evening, the bus parking problem consists of assigning these buses to parking slots in such a way that they can be dispatched adequately to the next morning routes without moving them between their arrivals and departures. In practice, the bus arrival times deviate stochastically from the planned schedule. In this paper, we introduce for this problem two solution approaches that produce solutions which are robust to variations in the arrival times. The first approach considers that each arrival can deviate from its planned arrival order (sooner or later) by at most k positions, where k is a predefined parameter. In the second approach, the objective aims at minimizing the expectation of a function positively correlated with the number of buses that make the planned solution infeasible because they arrive too late or too early. In both approaches, the problem is modeled as an integer linear program that can be solved by a commercial mip solver. Computational results obtained on instances derived from a real-world dataset are reported. Author Affiliation: Department of Mathematics and Industrial Engineering, Ecole Polytechnique and GERAD, Montreal, Que., Canada Article History: Received 23 February 2006; Accepted 23 October 2006

Inflammatory myofibroblastic tumor (IMT) is a rare neoplasm of children and young adults. It consists of myofibroblastic cells of borderline malignancy admixed with inflammatory cells. According to the WHO classification, of tumors, it is a soft-tissue tumor with an intermediate malignant potential. It may arise within numerous organs. Ureteral location is exceedingly rare. We report the exceptional case of a 4-year-old boy presenting with a giant right ureteral IMT removed during a nephroureterectomy. Histology and immunohistochemistry confirmed the diagnosis of an IMT with Anaplastic Lymphoma Kinase 1 expression. A 7 months follow-up showed no recurrence or distant metastasis. We also reviewed the literature for similar cases of pediatric ureteral IMT. [ABSTRACT FROM AUTHOR]

Adrenal Cavernous Hemangioma is an extremely rare histological type of adrenal tumors, typically asymptomatic and occasionally revealed by a symptom or complication. Here, we report an atypical symptomatic case to enrich the limited international case series. We present the case of an 80-year-old woman who underwent laparoscopic left adrenalectomy for a painful and potentially malignant left adrenal neoplasm, leading to the discovery of a five-centimeter adrenal cavernous hemangioma. The post-operative course was uneventful. The postoperative course was uneventful, and the chronic lumbar pain described initially vanished at the six-month follow-up. Adrenal cavernous hemangioma is typically silent and incidentally discovered on cross-sectional imaging. Symptomatic or complicated forms are extremely rare. Clinical, biological, radiological and histology assessment are crucial for management. Therapeutic decisions depend on the malignancy probability and the functional nature of the adrenal neoplasm, considering surgery versus conservative approaches. Patient's point-of-view and background are also determining factors in the decision-making process. Mini-invasive adrenalectomy is superior to open approach, when feasible and safe. Adrenal cavernous hemangioma is a rare benign vascular tumor often discovered on adrenalectomy specimen. This case illustrates a rare cause of chronic lumbar pain. It also underscores the importance of a multidisciplinary medical decision for this kind of tumors. • Adrenal Cavernous Hemangioma is a rare benign vascular tumor. • It is usually asymptomatic, occasionally revealed by a symptom or a complication. • The preoperative diagnosis is very challenging. • The Therapeutic decisions are based on the malignancy probability, functional nature of the adrenal neoplasm, and complications, balancing surgery versus a conservative approach. [ABSTRACT FROM AUTHOR]

Résumé De part leur fréquence et leur impact tant médical que socioprofessionnel, les affections respiratoires, notamment l'asthme, constituent un problème majeur de santé au travail. En effet, ces affections occupent actuellement le troisième rang parmi les maladies professionnelles déclarées à la CNAM en Tunisie. Objectifs Décrire les caractéristiques socioprofessionnelles, cliniques et paracliniques de l'asthme professionnel (AP) en Tunisie dans le secteur privé, identifier les facteurs de risques professionnels à l'origine de cette affection, évaluer les conséquences médicolégales de cette maladie professionnelle. Méthodes Étude transversale descriptive et rétrospective ayant porté sur l'ensemble des cas d'asthme professionnel reconnus au titre des maladies professionnelles et indemnisés dans la région nord de la Tunisie, étudiés par les commissions médicales habilitées à fixer le taux d'incapacité partielle permanente aux victimes des accidents de travail et des maladies professionnelles durant une période de 15 ans (2002–2016). Résultats Au total, 127 dossiers d'asthme professionnel ont été colligés entre janvier 2002 et décembre 2016 au niveau de la région nord de la Tunisie, ce qui correspond à une proportion de 11 % par rapport à l'ensemble des maladies professionnelles reconnues durant cette période. La moyenne d'âge des patients était de 40,47 ans avec une légère prédominance féminine (59 %). La durée moyenne d'exposition était de 13,92 ans. Le secteur d'activité le plus concerné était l'industrie de confections et de textiles (33,07 %) avec une recrudescence du secteur des accessoires automobiles (15,74 %) dans la région du nord tunisien. Les allergènes auxquels les salariés étaient exposés étaient principalement les poussières textiles et végétales dont le coton (32,28 %), suivis par les isocyanates (22,83 %), l'aldéhyde formique (9,44 %) et la farine (8,66 %). L'association de la rhinite allergique professionnelle à un asthme professionnel était rapportée chez 26/127 cas. La rythmicité des manifestations respiratoires avec le travail a été rapportée dans 89 % des cas. Cet asthme était à l'origine de 13 712 jours de travail perdus et d'un taux IPP moyen de 22 %. Plus des 2/3 de notre population (70 %) ont perdu leur emploi après l'indemnisation. Conclusion Le pronostic de l'asthme professionnel dépend d'un diagnostic précoce et rigoureux et l'établissement d'une démarche consensuelle dans les pratiques de réparation et d'indemnisation adaptée à la réalité de notre pays. Abstract Because of their frequency and their medical and socioprofessional impact, respiratory diseases, particularly asthma, are a major occupational health problem. Indeed, these diseases are currently the third most common occupational disease reported to the CNAM in Tunisia. Objectives To describe the socioprofessional, clinical and paraclinical characteristics of occupational asthma in Tunisia in the private sector, to identify the occupational risk factors that cause this disease, and to evaluate the medicolegal consequences of compensation for this occupational disease. Methods A descriptive and retrospective cross-sectional study covering all cases of occupational asthma recognized as occupational diseases and compensated in the northern region of Tunisia, studied by medical commissions empowered to set rates for permanent partial disability caused by either a work-related injury or an occupational disease over a period of 15 years (2002–2016). Results A total of 127 cases of occupational asthma were collected between January 2002 and December 2016 in the northern region of Tunisia, corresponding to 11% of all occupational diseases recognized during this period study. The average patient age of is 40.47 years, with a slight predominance among females (59%). The average duration of exposure is 13.92 years. The sector most concerned is the clothing and textile industry (33.07%), with a rise in the automotive accessories sector (15.74%) in the northern region of Tunisia. The allergens to which workers were exposed were mainly textile and vegetable dust, including 32.28% cotton. In second place were isocyanates with 29 cases (22.83%), followed by formic aldehyde (9.44%) and flour 8.66%. Association of occupational allergic rhinitis with occupational asthma was reported in 26/127 cases. In total, 13,712 working days were lost and the average IPP rate was 22%; 70% of our population are no longer active and have lost their jobs after compensation. Conclusion The prognosis of occupational asthma depends on early and rigorous diagnosis as well as the establishment of a consensual approach in the compensation practices adapted to the actual situation prevailing in our country. [ABSTRACT FROM AUTHOR]

We show that the probability distribution corresponding to a fully random tracial state of a system of spin-S particles satisfies a diffusion-like equation. The diffusion coefficient turns out to be equal to S ( S + 1 ) / 6 , where S is the magnitude of the spin of each particle. We also present a bosonization scheme for the lowering and raising total spin operators. [ABSTRACT FROM AUTHOR]

Developing ecological insulation of unfired building materials will not only reduce energy consumption of bill houses but will assure also sustainability, especially for Bensmim region which is a poor area, cold and the main activity of its inhabitant is the elevation of sheep, so the wool is a very abundant and affordable material. For this purpose, a series of experimental studies were performed on the composite clay–wool in different percentage of wool. The first step in this work is the physic-chemical characterization of clay using the fluorescence X method. The second step is the thermal characterization of clay alone and the composite clay–wool using the asymmetrical hot plate and flash methods. The third step in the work is the verification of thermal conductivity using different theoretical models. The fourth step in this work is the study of thermal Inertia of different wall's thickness of the materials: clay, clay–3%wool and clay–5%wool. By asserting all of the depth of heat flow diffusion, the delay of temperatures, the delay of heat flow density and the damping factor for different wall's thickness for the three materials. The obtained results indicate that those developed composites show off interesting characteristics in term of insulation and thermal Inertia. Those results attend above 11 h of delay on (temperature, heat flow density), 0.27 of damping factor and 0.19 W m −1 k −1 of thermal conductivity. Also, a comparison of heating energy need was conducted to a whole building model demonstrating that the composite clay–wool presents the best energy efficiency of envelope building. [ABSTRACT FROM AUTHOR]

From mathematical and numerical points of view, we study the sensitivity with respect to parametric evolutions, of the error obtained by approximating a given parametric partial differential equation using a proper orthogonal decomposition (POD) basis determined once and for all, with association to a fixed parameter. More precisely, we will be considering the one-dimensional Burgers equation with a source term. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we present contributions concerning a mathematical study of the sensitivity of a reduced order model (ROM) by the proper orthogonal decomposition (POD) technique applied to a quasi-linear parabolic equation. In particular, we apply our theoretical study to the Navier–Stokes equations for a 2D incompressible fluid flow. We present a numerical test of our theoretical result, for an unsteady fluid flow in a channel around a circular cylinder. [Copyright &y& Elsevier]

• Time integrator. • Stiff equations. • Stability. • Borel summation. • Divergent series. A stability analysis of the Borel–Padé–Laplace series summation technique, used as explicit time integrator, is carried out. Its numerical performance on stiff and non-stiff problems is analyzed. Applications to ordinary and partial differential equations are presented. The results are compared with those of many popular schemes designed for stiff and non-stiff equations. [ABSTRACT FROM AUTHOR]

Abstract: The two-dimensional Burgers’ equations are solved here using the A Priori Reduction method. This method is based on an iterative procedure which consists in building a basis for the solution where at each iteration the basis is improved. The method is called a priori because it does not need any prior knowledge of the solution, which is not the case if the standard Karhunen–Loéve decomposition is used. The accuracy of the APR method is compared with the standard Newton–Raphson scheme and with results from the literature. The APR basis is also compared with the Karhunen–Loéve basis. [Copyright &y& Elsevier]

Abstract: We derive analytical properties for the degeneracy occurring in the decomposition of the state space . We also investigate the dynamics of two qubits coupled via Ising interactions to separate spin baths, and we study the thermodynamic limit. [Copyright &y& Elsevier]

Abstract: We study the effect of nitrogen content in modulation-doped GaAs/GaAs1− x N x /GaAs/GaAlAs:(Si) quantum well using low-temperature photoluminescence spectroscopy. The samples were grown on GaAs (001) substrates by molecular-beam epitaxy with different nitrogen compositions. The variation of the nitrogen composition from 0.04% to 0.32% associated to the bi-dimensional electron gas gives a new interaction mode between the nitrogen localized states and the GaAs1− x N x /GaAs energies levels. The red-shift observed in photoluminescence spectra as function of nitrogen content has been interpreted in the frame of the band anticrossing model. [Copyright &y& Elsevier]

Abstract: Navier–Stokes equations have fundamental properties such as the invariance under some transformations, called symmetries, which play an important role in the description of the physics of the equations (conservation laws, wall laws, …). It is essential that turbulence models do not violate these properties. An analysis of a large set of subgrid models, according to the respect of the symmetries of Navier–Stokes equations is then done. As this analysis reveals that only few of the existing models are consistent with the symmetries, a new class of compatible models is proposed. This class is refined such that the models also respect the second law of thermodynamics. Finally, it is shown that this thermodynamic requirement leads to the stability of the model. [Copyright &y& Elsevier]

Abstract: In this paper, we present a non-linear one-dimensional model for thin-walled rods with open strongly curved cross-section, obtained by asymptotic methods. A dimensional analysis of the non-linear three-dimensional equilibrium equations lets appear dimensionless numbers which reflect the geometry of the structure and the level of applied forces. For a given force level, the order of magnitude of the displacements and the corresponding one-dimensional model are deduced by asymptotic expansions. [Copyright &y& Elsevier]

Abstract: We report a low-temperature photoluminescence spectra (LTPL) of GaAs1−x N x layers and two-dimension electron gas (2DEG) GaAs1−x N x /AlGaAs modulation doped heterostructure grown on GaAs substrates by molecular beam epitaxy (MBE) with low nitrogen content [N]=2×1018 cm−3. At low temperature, PL spectra of GaAs1−x N x layers are governed by several features associate to the excitons bound to nitrogen complexes, these features disappear in (2DEG) GaAs1−x N x /AlGaAs modulation doped heterostructure and the PL peak energy decrease with the laser power excitation. This effect is explained by the strongly coupling of the (2DEG) fundamental state with the nitrogen localized states. An activated energy of about 55meV is deduced by photoluminescence measurements in the 10–300K range for a laser power excitation P =6W/cm2. [Copyright &y& Elsevier]

The purpose of this article is to develop an asymptotic Eulerian approach in plate and shell theory valid for large displacements. With this Eulerian approach, the dead load assumption generally used with Lagrangian approaches can be dropped. We also obtain a membrane model which takes into account following forces, whose direction can vary during large displacements. [Copyright &y& Elsevier]

The line intensities of the ν3 band of OCS used for atmospheric retrievals, has been measured. The spectra have been recorded with the Reims Fourier transform spectrometer. Other bands of OCS 4ν2, ν1+ν3, 3ν1 and 2ν1+2ν2 were recorded to obtain the line intensities. The results are compared to usual databanks (HITRAN or GEISA). From the measured line intensities, it has been possible to estimate the square of the vibrational dipole moment matrix element (in debye2), equal to 0.13131, 7.8409×10−4, 1.1581×10−3, 1.2183×10−5, 1.1923×10−5, respectively, for ν3, 4ν2, ν1+ν3, 3ν1 and 2ν1+2ν2. [Copyright &y& Elsevier]

The urgency of addressing climate change, energy security, and ecological concerns has driven the global shift towards renewable energy systems. In this transformative era, green hydrogen emerges as a pivotal energy resource, promising substantial reductions in global emissions. Methods like water electrolysis, biomass gasification, and methane reforming with carbon capture and storage offer pathways to synthesize hydrogen without greenhouse gas emissions. Currently, hydrogen accounts for approximately 4% of global energy generation, with projections suggesting this could increase to 10% by 2030 and 20% by 2050. Integrating nuclear energy into hydrogen production presents a low-carbon option, promoting reliability and meeting growing demand across sectors. For instance, incorporating nuclear energy could reduce emissions by up to 90% compared to conventional methods. Categorizing hydrogen production into colors based on emissions provides a framework for understanding their environmental and socio-economic profiles. For example, green hydrogen can reduce lifecycle emissions by 60–90% compared to gray hydrogen. Life cycle analysis aids in evaluating overall impacts, guiding policy formulation and industrial decisions towards sustainability. This review examines various production pathways, highlighting their potential contributions to a carbon-neutral economy and discussing the hydrogen spectrum's role in characterizing production processes based on carbon emissions. [Display omitted] • H 2 spectrum characterizes manufacturing processes based on carbon emissions. • Renewable hydrogen reduces emissions more effectively than gray hydrogen. • Nuclear hydrogen has a low impact using Cu–Cl thermochemical cycles. • Multifaceted approaches needed to overcome hydrogen production challenges. [ABSTRACT FROM AUTHOR]

This paper presents an application of DKMQ plate bending element to analyze composite structures. DKMQ element is an element proposed by Katili that passed the patch test and gives good results in many plate bending applications. It can be used to analyze thick and thin plate problem without shear locking. The application of DKMQ plate bending element for composite plate has been analyzed; the convergence of displacement is presented. As validation, the solution of Srinivas and Pagano are employed. Moreover, measuring the convergence using the s-norm is addressed. DKMQ plate bending element gives a good performance and can be used as one of tools in analyzing composite structure. [ABSTRACT FROM AUTHOR]

Abstract: A set of GaAs1− x N x samples with small nitrogen content were investigated by photoluminescence (PL) measurements as function of irradiance in order to investigate the effect of rapid thermal annealing (RTA) on photoluminescence (PL) properties. The analysis of PL spectra as function of irradiance and nitrogen content shows that the PL spectra associated to the GaAs1− x N x layers are the result of the nitrogen localized state recombination. The results are examined as a consequence of a rapid thermal annealing (RTA). The variation of the emission band peak energy (E p), at 10K as a function of irradiance, is fitted by a theoretical model taking into account two types of nitrogen localized states. The variation of the PL intensity versus irradiance in the range from 1.59 to 159W/cm2 for different GaAs1− x N x samples confirm that the PL spectra result from the nitrogen localized state recombination. [Copyright &y& Elsevier]

The two-dimensional flow along an inclined plate may be detached or reattached to the plate by Coanda effect. Experimentally, we explore the influence of the inclination angle and of the Reynolds number on the attachment and detachment phenomena, and on the hysteresis loop. A proper orthogonal decomposition (POD) of the flow is applied to a LES simulation resulting data. A low-dimensional dynamical model is obtained using by Galerkin projection of the Navier–Stokes equations upon the POD basis functions. We show that this model represents qualitatively the characteristics of the flow. [Copyright &y& Elsevier]

We propose in this paper to generalize to elastic–plastic plates the constructive asymptotic approach developed by the authors for elastic plates and shells. A dimensional analysis of three-dimensional equations makes appear dimensionless numbers characterizing the problem. Then using the geometric and mechanical data, these dimensionless numbers are linked to the perturbation parameter (the relative thickness of the plate) to obtain a one scale problem. For standard generalized materials with strong strain hardening, subjected to usual force levels, the asymptotic expansion of equations leads to an elastic–plastic plate model valid for moderate displacements. The constructive approach developed enables to specify the domain of validity of the asymptotic elastic–plastic plate model obtained thanks to the dimensional numbers introduced. [Copyright &y& Elsevier]