Existence results for non-smooth second order differential inclusions, Convergence result for a numerical scheme and applications for modelling inelastic collisions

We are interested in existence results for second order differential inclusions, involving finite number of unilateral constraints in an abstract framework. These constraints are described by a set-valued operator, more precisely a proximal normal cone to a time-dependent set. Moreover we extend a numerical scheme, introduced in [8] and proved a convergence result. We propose applications in modelling inelastic collisions between rigid particles too.Comment: 22 pages, 1 figur

An Investigation Into Current Procurement Strategies That Promote Collaboration Through Early Contractor Involvement With Regards to Their Suitability for Irish Public Work Projects

Previous research has established that multi-disciplinary collaboration will benefit a construction project throughout its lifecycle. While Lean Construction, Building Information Modelling (BIM), and Integrated Project Delivery (IPD) can all be viewed as separate processes which add independent value to a project, they are more effective when used in partnership with each other. In order to ensure the high levels of collaboration expected for these processes to work in unison, the early involvement of the Contractor is paramount. Early contractor involvement within the design process can ensure a more focused integrated project team, improvement of both constructability and cost certainty, as well as better risk management. This approach has only been used occasionally on Irish public works projects. Competitive tendering has resulted in creating a culture of claims and adversity, not conducive to collaboration and therefore raising the question, is the traditional procurement format representing value for money for the Irish State. This paper will investigate current procurement strategies that promote early contractor involvement and their suitability for Irish public works projects. The research will primarily focus on contracts that are best aligned to the Capital Works Management Framework (CWMF) strategic objectives of ensuring greater cost certainty, better value for money and more efficient end-user delivery. To achieve this an initial literature review was undertaken exploring award criteria for early Contractor involvement both within the International and Irish public and private sectors. This research focused on establishing and examining the potential barriers for implementation. The analysed data from this process was interrogated through Stakeholders interviews that aimed to understand the current state of the public work project procurement process and if government agencies would endorse a move away from the “lowest bid win” criteria for contractor selection. A case study was also carried out showcasing a form of IPD used in Ireland. The findings from this paper suggest that early contractor involvement in partnership with IPD can provide a more advantageous solution for the Irish State while also promoting both BIM and Lean Construction processes

An Investigation Into Current Procurement Strategies That Promote Collaboration Through Early Contractor Involvement With Regards to Their Suitability for Irish Public Work Projects

Previous research has established that multi-disciplinary collaboration will benefit a construction project throughout its lifecycle. While Lean Construction, Building Information Modelling (BIM), and Integrated Project Delivery (IPD) can all be viewed as separate processes which add independent value to a project, they are more effective when used in partnership with each other. In order to ensure the high levels of collaboration expected for these processes to work in unison, the early involvement of the Contractor is paramount. Early contractor involvement within the design process can ensure a more focused integrated project team, improvement of both constructability and cost certainty, as well as better risk management. This approach has only been used occasionally on Irish public works projects. Competitive tendering has resulted in creating a culture of claims and adversity, not conducive to collaboration and therefore raising the question, is the traditional procurement format representing value for money for the Irish State. This paper will investigate current procurement strategies that promote early contractor involvement and their suitability for Irish public works projects. The research will primarily focus on contracts that are best aligned to the Capital Works Management Framework (CWMF) strategic objectives of ensuring greater cost certainty, better value for money and more efficient end-user delivery. To achieve this an initial literature review was undertaken exploring award criteria for early Contractor involvement both within the International and Irish public and private sectors. This research focused on establishing and examining the potential barriers for implementation. The analysed data from this process was interrogated through Stakeholders interviews that aimed to understand the current state of the public work project procurement process and if government agencies would endorse a move away from the “lowest bid win” criteria for contractor selection. A case study was also carried out showcasing a form of IPD used in Ireland. The findings from this paper suggest that early contractor involvement in partnership with IPD can provide a more advantageous solution for the Irish State while also promoting both BIM and Lean Construction processe

Synthesis, structure and characterization of a new cadmium(II) iodide containing a tetradentate tripodal amine

A cadmium(II) iodide compound of the [Cd(L)I]I series, with L = tris(2-aminoethyl)amine, is synthesized and characterized. X-ray structural study shows that the title compound has a slightly distorted trigonal bipyramidal environment where the CdN4I chromophore is bounded by N atoms of L and one iodide. In the structural arrangement, the [Cd(L)I]+ cationic complexes are interconnected via N-H···I hydrogen bonds generated by the uncoordinated I iodide anions to form layers parallel to the (a, c) plane. The 13C CP-MAS NMR spectrum is discussed and the vibrational absorption bands were identified by infrared spectroscopy and DFT calculations

Synthesis, structure and characterization of a new noncentrosymmetric Zn(II) complex with the 2-amino-5-chloropyridine ligand (AClPy)

A new noncentrosymmetric Zn(II) complex with the monodentate ligand 2-amino-5-chloropyridine (AClPy), ZnCl2(C5H5ClN2)2, has been prepared at room temperature and characterized by single crystal X-ray diffraction, 13C CP-MAS-NMR and IR spectroscopies. The basic coordination pattern of the AClPy coordinated metal cations is slighly distorted tetrahedral. The crystal structure is characterized by ZnCl2N2 tetrahedra interconnected via N-H···Cl hydrogen bonds generated by the NH2 amino group to form chains extending along the (a-c) direction. The exocyclic N atom is an electron receiving center, which is consistent with features of imino resonance as evidenced by bond lengths and angles. The crystal structure is stabilized by sets of intra and intermolecular hydrogen bonds. The 13C CP-MAS NMR spectrum is discussed and the vibrational absorption bands are identified by infrared spectroscopy and theoretical calculations

How do general dental practitioners perceive and deal with orthodontic bonded retainers?

Introduction: Long-term follow-up and management of orthodontic bonded retainers require a strong collaboration between orthodontists and general dental practitioners (GDPs). This study aimed to evaluate if Eastern French GDPs were aware of bonded retainers' complications and side effects and if they were willing to take part in their long-term follow-up. Methods: Two-hundred and eighteen randomly selected GDPs were invited to answer an online questionnaire. The initial sections covered their experience and management with bonded retainers. In the final sections, GDPs were asked their opinion on the responsibility for long-term follow-up of patients wearing fixed retainers and on the mutual communication between orthodontists and GDPs. Statistical analysis involved descriptive statistics and Fisher exact tests. Results: Response rate was 32.6% (n 5 71). The vast majority of GDPs were familiar with loose retainers, but only 45.2% were willing to repair them. Respondents offering orthodontic services on a regular basis were more likely to insert retainers and repair loose or broken retainers (P \ 0.001). Approximately 18.6% of GDPs were aware of third-order side effects encountered with unintentionally active retainers bonded to all 6 anterior teeth. For 88.8% of GDPs, permanent retention was justified, whereas 90% of the dentists refused to be responsible for longterm supervision of fixed retainers. In addition, 67.1% were interested in further training on orthodontic retention, and 92.9% would appreciate clinical guidelines. Conclusions: Knowledge about the harmful side effects of bonded retainers was evaluated as insufficient among surveyed GDPs. Long-term follow-up of patients wearing bonded retainers raises issues that should be addressed globally by enhancing mutual communication, practitioners' education, and patients' involvement. (Am J Orthod Dentofacial Orthop 2021;160:e1-e8

4-Acetamido­anilinium nitrate monohydrate

In the title hydrated salt, C8H11N2O+·NO3 −·H2O, the N—C bond distances [1.349 (2) and 1.413 (2) Å] along with the sum of the angles (359.88°) around the acetamide N atom clearly indicate that the heteroatom has an sp 2 character. The ammonium group is involved in a total of three N—H⋯O hydrogen bonds, two of these are with a water mol­ecule, which forms two O—H⋯O hydrogen bonds. All these hydrogen bonds link the ionic units and the water mol­ecule into infinite planar layers parallel to (100). The remaining two N—H⋯O inter­actions in which the ammoniun group is involved link these layers into an infinite three-dimensional network

Furfuryl­ammonium chloridozincophosphate

In the title compound, [ZnCl(HPO4)](C5H8NO), polymeric inorganic layers constructed from ZnO3Cl and PO4 tetra­hedra are linked by O atoms: O—H⋯O hydrogen bonds occur within the layers. The organic cations occupy the interlayer regions and interact with the layers by way of N—H⋯O, N—H⋯Cl, and C—H⋯Cl hydrogen bonds

A new generation of veryhigh stability BVA oscillators

International audienceA third generation of “Oscilloquartz” OCXO's using the technique of housing a BVA SC-cut crystal resonator and its associated oscillator components in double oven technology has been developed with the funding support of European Space Operations Centre (E.S.O.C). The main purpose is to provide a local oscillator for high performances ground clock. The main features targeted of that new “8607-C series” are to get significant improvements compared to the classical “state of the art” 8607-B design in a better short term stability @ 1 sec in Allan variance, a better-low phase noise and outstanding short term stability and a better-high isolation from “pressure and humidity” variations

Crystal structure, Hirshfeld surface analysis, and physicochemical studies of a new Cu(II) complex with 2-amino-4-methylpyrimidine

International audienceThe chemical preparation, crystal structure, magnetic study and spectroscopic characterization of the new Cu(II) complex with the monodentate ligand 2-amino-4-methylpyrimidine [Cu2(CH3COO)4(C5N3H7)2] are reported. The copper atoms are surrounded by one nitrogen atom from one 2-amino-4-methylpyrimidine ligand and four oxygen atoms of CH3COO − groups yielding to a penta-coordination of the metal ion. In the structural arrangement, the amino group and the pyrimidine nitrogen atom of neighboring molecules are linked together through a pair of N-H…N hydrogen bonds forming a 1-D corrugated chain running along the [111] direction wherein the complex molecules are located parallel to the (a, c) plane at z = ½. Intermolecular interactions were investigated by Hirshfeld surfaces and contact enrichment tools. Mulliken charge distribution, molecular electrostatic potential (MEP) maps and HOMO and LUMO energy gaps have been computed. The vibrational absorption bands were identified by infrared spectroscopy. Magnetic properties were also studied to characterize the complex