Characterising the dynamic response of ultrasonic cutting devices

The current work begins by considering a range of common high power ultrasonic components in order to establish a standardised approach to tool design for optimum performance. The vibration behaviour of tuned components resonating longitudinally at ultrasonic frequencies around 35 kHz is modelled via finite element analysis and measured by experimental model analysis. Significant improvements in experimental validation of the models are achieved by the use of a 3D LDV, which allows modal analysis from both in-plane and out-of-plane measurement, which is critical in proposing alternative designs. The vibration characteristics of complex multiple-component systems used in ultrasonic cutting of food products are also investigated. Commonly, the design approach for ultrasonic systems neglects to account for the mutual effects of physically-coupled components in the system vibration. The design of systems also neglects the nonlinear dynamic effects which are inherent in high power systems due to the nonlinearities of piezoelectric transducers. The first issue is tackled by considering the vibration behaviour of the whole system and the influence of individual components and, particularly, offers design improvements via modification of block horns and cutting blade components, which are modelled and validated. The issue of nonlinearity is addresses by identifying the mechanisms of energy leakage into audible frequencies and characterising the common multimodal responses. For this study, design modifications focused on reducing the number of system modes occurring at frequencies below the tuned system frequency. As a consequence of these approaches, insights for the design of multiple-component systems in general are provided

Nonlinear characterization of half and full wavelength power ultrasonic devices

It is well known that power ultrasonic devices whilst driven under elevated excitation levels exhibit nonlinear behaviors. If no attempt is made to understand and subsequently control these behaviors, these devices can exhibit poor performance or even suffer premature failure. This paper presents an experimental method for the dynamic characterization of a commercial ultrasonic transducer for bone cutting applications (Piezosurgery® Device) operated together with a variety of rod horns that are tuned to operate in a longitudinal mode of vibration. Near resonance responses, excited via a burst sine sweep method were used to identify nonlinear responses exhibited by the devices, while experimental modal analysis was performed to identify the modal parameters of the longitudinal modes of vibration of the assemblies between 0-80 kHz. This study tries to provide an understanding of the effects that geometry and material choices may have on the nonlinear behavior of a tuned device

Understanding nonlinear vibration behaviours in high-power ultrasonic surgical devices

Ultrasonic surgical devices are increasingly used in oral, craniofacial and maxillofacial surgery to cut mineralized tissue, offering the surgeon high accuracy with minimal risk to nerve and vessel tissue. Power ultrasonic devices operate in resonance, requiring their length to be a half-wavelength or multiple-half-wavelength. For bone surgery, devices based on a half-wavelength have seen considerable success, but longer multiple-half-wavelength endoscopic devices have recently been proposed to widen the range of surgeries. To provide context for these developments, some examples of surgical procedures and the associated designs of ultrasonic cutting tips are presented. However, multiple-half-wavelength components, typical of endoscopic devices, have greater potential to exhibit nonlinear dynamic behaviours that have a highly detrimental effect on device performance. Through experimental characterization of the dynamic behaviour of endoscopic devices, it is demonstrated how geometrical features influence nonlinear dynamic responses. Period doubling, a known route to chaotic behaviour, is shown to be significantly influenced by the cutting tip shape, whereas the cutting tip has only a limited effect on Duffing-like responses, particularly the shape of the hysteresis curve, which is important for device stability. These findings underpin design, aiming to pave the way for a new generation of ultrasonic endoscopic surgical devices

The balanced scorecard logic in the management control and reporting of small business company networks: a case study

The purpose of this paper is to assess and integrate the application of the balance scorecard (BSC) logic into business networks identifying functions and use that such performance measuring tool may undertake for SME’s collaborative development. Thus, the paper analyses a successful case study regarding an Italian network of small companies, evaluating how the multidimensional perspective of BSC can support strategic and operational network management as well as communication of financial and extra financial performance to stakeholders. The study consists of a qualitative method, proposing the application of BSC model for business networks from international literature. Several meetings and interviews as well as triangulation with primary and secondary documents have been conducted. The case study allows to recognize how BSC network logic can play a fundamental role on defining network mission, supporting management control as well as measuring and reporting the intangible assets formation along the network development lifecycle. This is the first time application of a BSC integrated framework for business networks composed of SMEs. The case study demonstrates operational value of BSC for SME’s collaborative development and success

La strategia nelle forme reticolari tra piccole e medie imprese. Un approccio processuale alla pianificazione

La necessit\ue0 di fronteggiare un contesto competitivo che evolve secondo schemi non lineari, contradditori e di alternanza tra momenti di stabilit\ue0 e di instabilit\ue0 sta sollecitando nuovi comportamenti strategici delle imprese, centrati sul potenziale della cooperazione inter-organizzativa (Smith et al., 1995). La considerazione di fondo \ue8 che la cooperazione consentirebbe l\u2019integrazione in forma collaborativa di processi e risorse per il conseguimento di un vantaggio competitivo comune, che, altrimenti, le singole imprese dovrebbero perseguire sfruttando ed adeguando la struttura interna o, in alternativa, sviluppando adeguate relazioni di scambio (Das, Teng, 2000). Tale considerazione \ue8 il nucleo centrale di un ampio dibattito scientifico che a partire da met\ue0 anni Ottanta ha visto un\u2019intensa proliferazione di contributi che approcciano il fenomeno inter-cooperativo applicando differenti teorie e modelli (es.: teoria dei costi di transazione, teoria dei giochi, teoria delle risorse, modello del comportamento strategico, modello del processo decisionale strategico). Il presente lavoro si inserisce all\u2019interno del dibattito scientifico summenzionato con il proposito di riflettere sul processo di formazione della strategia nelle forme reticolari tra piccole e medie imprese. Si intende, in tal modo, offrire un contributo empirico per rispondere alle sollecitazioni che invitano a orientare la ricerca sulle reti d\u2019impresa lungo la dimensione processuale, per avvicinare la conoscenza dell\u2019intricato insieme di scelte, eventi, situazioni, opportunit\ue0 che spiegano come il contenuto, la struttura e la governance della rete emergono ed evolvono nel corso del tempo (Hoang, Antoncic, 2013). A differenza della prevalente impostazione strategica sulle reti di impresa, che interpreta il problema strategico con riferimento ai benefici e ai rischi per la singola impresa derivanti dalla partecipazione al sistema relazionale inter-organizzativo (Gulati et al., 2000), il presente lavoro pone al centro il network ed affronta il tema della formazione della strategia competitiva dei network di piccole e medie imprese. Proprio tenendo in esplicita considerazione le peculiarit\ue0 dell\u2019oggetto di studio, si focalizza l\u2019attenzione sul processo di formazione strategica utilizzando un modello ed una metodologia che hanno quale loro epicentri il costrutto della visione strategica (Gluck, 1984) e la mappatura strategica (Ackermann, Eden, 2011). Dopo aver inquadrato il concetto di forma reticolare utile ai fini del presente lavoro, si affronta il tema della formazione strategica dapprima introducendo il modello di riferimento e le sue fasi fondamentali e, successivamente, focalizzando l\u2019attenzione sulla fase della mappatura della visione strategica imprenditoriale. Particolare enfasi sar\ue0 attribuita alla visualizzazione strategica quale strumento utile per la rappresentazione e la condivisione del pensiero strategico individuale e collettivo. Infine, si riportano le prime evidenze empiriche tratte dal progetto di ricerca-azione attualmente in esecuzione

An analytical framework for strategic alliance formation between a cooperative bank and a fintech start-up : an Italian case study

CEL: Celem artykułu jest identyfikacja cech charakteryzujących analizowane podmioty, motywacje oraz procesy tworzenia aliansów strategicznych pomiędzy małym bankiem spółdzielczym a start-upem typu fintech. Artykuł wypełnia lukę badawczą w literaturze dotyczącej tej tematyki oraz wyjaśnia czynniki sukcesu aliansu strategicznego zawieranego pomiędzy badanymi podmiotami. METODYKA: Zastosowano jakościowe podejście badawcze, które składa się z dwóch etapów. Pierwszym krokiem było opracowanie ram analitycznych, umożliwiających zrozumienie kluczowych czynników sukcesu w tworzeniu aliansów strategicznych między bankami i start-upami typu fintech. W drugim kroku zastosowano ramy analityczne do analizy studium przypadku, którym był alians strategiczny pomiędzy Banca Popolare di Cortona i start--upem NetFintech. WYNIKI: Z przeprowadzonych badań wynika, że istnieją różne motywy tworzenia aliansów strategicznych między bankami i start-upami typu fintech. Z teoretycznego puntu widzenia motywacje banków opierają się na outsourcingu, innowacjach, ewolucji modelu biznesowego, przewadze konkurencyjnej, oszczędnościach, poprawie jakości świadczonych usług oraz uczenia się. Główne motywy fintechów to dostęp do klientów, pożyczki, licencja bankowa, ekonomia skali, zaufanie i wiarygodność. W części empirycznej ustalono, że głównymi czynnikami sukcesu są strategiczne dopasowanie i hybrydyzacja, kompetencje i doświadczenie, wartość kulturowa i bliskość terytorialna oraz profesjonalizm. IMPLIKACJE: Wyniki poszerzają wiedzę na temat aliansów strategicznych między bankami spółdzielczymi i start-upami typu fintech. Głównym ograniczeniem jest to, że artykuł opiera się tylko na jednym studium przypadku i dotyczy wyłącznie banków spółdzielczych, pomijając inne rodzaje banków. Może on być punktem wyjścia do dalszych badań w tym obszarze. Opisane studium przypadku może być dobrym przykładem do porównywania innych przypadków takich aliansów. Banki spółdzielcze i fintechy typu start-up zaangażowane w alianse strategiczne powinny dzielić swoje zaangażowanie na poziomie zarządzania. Istotne są również procedury tworzenia aliansów strategicznych. ORYGINALNOŚĆ I WARTOŚĆ: Artykuł wnosi istotny wkład do dotychczasowych badań na temat transformacji sektora bankowego pod wpływem technologii finansowych w dwóch obszarach. Po pierwsze opracowaliśmy teoretyczny model kluczowych czynników sukcesu podczas budowania aliansów strategicznych między bankami a start-upami typu fintech. Po drugie, zastosowaliśmy nasz model w kontekście kształtowania aliansów strategicznych między bankami i startupami na lokalnym rynku we Włoszech. W przeciwieństwie do wcześniejszych badań, które dotyczą głównie banków komercyjnych, nasz artykuł dotyczy relacji między bankami spółdzielczymi i start-upami typu fintech.PURPOSE: The paper aims to identify the characteristics of the entities involved, the motivations and the processes of forming strategic alliances between a small cooperative bank and a fintech start-up. The paper bridges the research gap in the literature and explains the success factors of strategic alliance between considered entities. METHODOLOGY: We applied a typical qualitative research approach that consists of two steps. The first step was to develop an analytical framework to understand the critical success factors for the strategic alliance formation between banks and fintech start-ups. In the second step, we applied the analytical framework for a case study analysis, considering the strategic alliance between the Banca Popolare di Cortona and the NetFintech start-up. FINDINGS: Our research shows that there are different motives for strategic alliance formation for banks and fintech startups. From a theoretical point of view, banks’ motivations are based on outsourcing, innovation, the evolution of the business model, competitive advantage, saving costs, improving service quality, and learning. The main motives for fintechs include access to customers, loans, banking license, economies of scale, trust, and credibility. In the empirical part, we found that the crucial success factors are strategic alignment and hybridization, competence and experience, cultural value and territorial closeness, and professionalism. IMPLICATIONS: The results develop the knowledge about the best conditions for cooperative banks and fintech start-ups strategic alliances. The main limitation is that the paper is based only on one case study and it is related to cooperative banks and does not embrace other groups of banks. For this reason, it can be a basis for further research in this area. The described case study can be a good example to compare other cases of such alliances. Cooperative banks and fintech start-ups involved in a strategic alliance should share the commitment at the governance level. Critical are also the procedures of the alliance formation. ORIGINALITY AND VALUE: This article provides two main contributions to the literature on the technology-driven transformations of the banking sector. First, we elaborated a theoretical framework of the critical success factors for the bank and fintech start-up strategic alliance formation. Second, we applied the framework with the bank–fintech start-up cooperation in the local market in Italy. Contrary to previous research, which focuses mainly on commercial banks, this article presents the relationship between cooperative banks and fintech start-ups

Nonlinear Dynamic Modeling of Langevin-Type Piezoelectric Transducers

Langevin transducers are employed in several applications, such as power ultrasound systems, naval hydrophones, and high-displacement actuators. Nonlinear effects can influence their performance, especially at high vibration amplitude levels. These nonlinear effects produce variations in the resonant frequency, harmonics of the excitation frequency, in addition to loss of symmetry in the frequency response and “frequency domain hysteresis”. In this context, this paper presents a simplified nonlinear dynamic model of power ultrasound transducers requiring only two parameters for simulating the most relevant nonlinear effects. One parameter reproduces the changes in the resonance frequency and the other introduces the dependence of the frequency response on the history of the system. The piezoelectric constitutive equations are extended by a linear dependence of the elastic constant on the mechanical displacement amplitude. For introducing the frequency hysteresis, the elastic constant is computed by combining the current value of the mechanical amplitude with the previous state amplitude. The model developed in this work is applied for predicting the dynamic responses of a 26 kHz ultrasonic transducer. The comparison of theoretical and experimental responses, obtained at several input voltages around the tuned frequency, shows a good agreement, indicating that the model can accurately describe the transducer nonlinear behavior.We would like to thank the research agencies: PEDECIBA and CSIC of Uruguay, FAPESP and CNPq from Brazil and ‘Ministerio de Economía y Competitividad’ of Spain (Projects: DPI2012-37466-C03-01 and PTQ-09-02-017691).We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe

A data-driven analysis of the current debate on the linkages between performance and strategy studies

This paper focuses on how the relations between performance management and measurement (PMM) and strategy are considered by scholars. These relations are crucial in building a comprehensive body of knowledge of a complex and multifaceted phenomenon which attracts scholars pertaining to different management disciplines. The results obtained by adopting quantitative methodologies (descriptive statistics and text-mining analysis) on a sample of articles recently published in the most influential international 'business, and management accounting' journals, contribute to extant literature by providing evidence that several connections exist between key-concepts which are usually considered an exclusive heritage of single management disciplines, such as strategy, organisation, management control, and so forth. For that reason, an integration of competences and methodologies is needed to support further research in the field. We also find evidence suggesting that the organisational perspective should be particularly considered when investigating the relations between strategy, management control systems and PMM

CRAS e território: relato de experiência em um Centro de Convivência e Fortalecimento de Vínculos / CRAS and territory: experience report in a center for acquaintanceship and strengthening bonds

O presente trabalho tem por objetivo relatar a experiência de estágio de alunas de um curso de graduação em Psicologia em um Centro de Convivência e Fortalecimento de Vínculos (CCFV). Foram realizados grupos com crianças com o objetivo de trabalhar questões relativas às suas vivências cotidianas e as emoções dali advindas. Em todas as intervenções utilizou-se como mediadores do processo grupal materiais artísticos e lúdicos, incluindo desenho, sucata, contação de histórias e brincadeiras diversas. Observou-se que os temas mais frequentemente expressos pelas crianças, através de suas falas e de suas produções artísticas, relacionavam-se ao vínculo com a mãe e familiares, perdas e conflitos e aqueles marcados por diferenciações de gênero. Além de relevante por possibilitar ao grupo de crianças o (re)criar e o (re)pensar de sentimentos, ações, relações e vivências, a experiência de estagiar em um CCFV evidenciou inúmeras dificuldades e desafios, como a rotatividade dos funcionários e a precariedade do serviço e do vínculo com o Centro de Referência de Assistência Social (CRAS)

Paediatric-type diffuse high-grade gliomas in the 5th CNS WHO Classification

As a relevant element of novelty, the fifth CNS WHO Classification highlights the distinctive pathobiology underlying gliomas arising primarily in children by recognizing for the first time the families of paediatric-type diffuse gliomas, both high-grade and low-grade. This review will focus on the family of paediatric-type diffuse high-grade gliomas, which includes four tumour types: 1) Diffuse midline glioma H3 K27-altered; 2) Diffuse hemispheric glioma H3 G34-mutant; 3) Diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype; and 4) Infant-type hemispheric glioma. The essential and desirable diagnostic criteria as well as the entities entering in the differential will be discussed for each tumour type. A special focus will be given on the issues encountered in the daily practice, especially regarding the diagnosis of the diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype. The advantages and the limits of the multiple molecular tests which may be utilised to define the entities of this tumour family will be evaluated in each diagnostic context