Relevant bibliographies by topics / Impulsi laser

Academic literature on the topic 'Impulsi laser'

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Published: 11 March 2023

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Journal articles on the topic "Impulsi laser"

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Phipps, C. R., and M. M. Michaelis. "LISP: Laser impulse space propulsion." Laser and Particle Beams 12, no. 1 (March 1994): 23–54. http://dx.doi.org/10.1017/s0263034600007217.

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It is not often that a new form of transportation suddenly appears and replaces what was hitherto regarded as mankind's only realistic option. In space and upper atmosphere transportation, chemical rockets have held center stage for over half a century. Tsiokolvsky's ideas led to Wernher von Braun's V2, which in turn led to the Soyuz, Apollo, and Ariane programs and the Space Shuttle. But recently theoretical and computational studies as well as a few initial experiments have pointed to a new option: laser impulse space propulsion (LISP). This may offer a more efficient and less ecologically damaging means of putting payloads into orbit. The world high-power laser community is well suited to following and aiding developments in LISP, though most practical research is still at an embryonic level. Obviously an effort of the size required to develop a laser-driven low-earth-orbit (LEO) launcher would require a multinational commitment. LISP could then be regarded as a parallel challenge to those of achieving ICF rriicrofusion yield and of improving X-ray lasers, especially in the “water window.” Any physicist or engineer involved with the latter projects would find many points in common with the former. It therefore seems appropriate to briefly review the progress made in LISP and also to communicate some recent results from high-power laser-matter experiments that have lead to conceptual designs.
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Chen, Peiyu, Mostafa Hosseini, and Aydin Babakhani. "An Integrated Germanium-Based THz Impulse Radiator with an Optical Waveguide Coupled Photoconductive Switch in Silicon." Micromachines 10, no. 6 (May 31, 2019): 367. http://dx.doi.org/10.3390/mi10060367.

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This paper presents an integrated germanium (Ge)-based THz impulse radiator with an optical waveguide coupled photoconductive switch in a low-cost silicon-on-insulator (SOI) process. This process provides a Ge thin film, which is used as photoconductive material. To generate short THz impulses, N++ implant is added to the Ge thin film to reduce its photo-carrier lifetime to sub-picosecond for faster transient response. A bow-tie antenna is designed and connected to the photoconductive switch for radiation. To improve radiation efficiency, a silicon lens is attached to the substrate-side of the chip. This design features an optical-waveguide-enabled “horizontal” coupling mechanism between the optical excitation signal and the photoconductive switch. The THz emitter prototype works with 1550 nm femtosecond lasers. The radiated THz impulses achieve a full-width at half maximum (FWHM) of 1.14 ps and a bandwidth of 1.5 THz. The average radiated power is 0.337 μ W. Compared with conventional THz photoconductive antennas (PCAs), this design exhibits several advantages: First, it uses silicon-based technology, which reduces the fabrication cost; second, the excitation wavelength is 1550 nm, at which various low-cost laser sources operate; and third, in this design, the monolithic excitation mechanism between the excitation laser and the photoconductive switch enables on-chip programmable control of excitation signals for THz beam-steering.
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موسى, عصام. "اختيار نظام لحام صفائح من النيكل بالليزر وتأثير بارامترات هذا النظام في أبعاد الدرزات اللحامية الناتجة." FES Journal of Engineering Sciences 3, no. 1 (November 6, 2008): 10. http://dx.doi.org/10.52981/fjes.v3i1.73.

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The effect of Laser welding system’s parameters on the dimensions of Nickel welded joint with thickness not more than (1.0 mm) was studied. The principal parameters of impulsed Laser in this case , which had influence on the welded spot’s dimensions ( spot’s diameter D & penetration h ) , are : the power of Laser beam , impulse time & the focusing distance of Laser beam to the welded joint. It was resulted that the values of dimension ( h ) increased (with high accelerating ) by the increasing of Laser beam’s power & impulse time & the decreasing of focusing distance , but the values of dimension D increased very slowly by the changes of above – mentioned parameters , and as result the values of melting form’s coefficient (Ψ = D / h ) decreased & reached the minimum when the melting penetration was about 1.0 mm ( the thiclness of Nickel plate ) . The micro-structure studying of cross sections in the welded joints showed that if the power of Laser beam was so high that the tmperature of welded spot was so high than the meting point of welded metal, the latest one obsorbed a lot of gases from the surrounded atmosphere and variuos defects were noticed in this weld metal. So, it’s too important to use a sheilding gas ( like Argon ) to improve the reaction of these gases with the weld metal .
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Arestova, N. N., N. S. Egiyan, T. B. Kruglova, and R. V. Kalinichenko. "Prevention of IOL Laser Damage after YAG Laser Destruction in Children with Secondary Cataract." Ophthalmology in Russia 18, no. 2 (July 5, 2021): 245–52. http://dx.doi.org/10.18008/1816-5095-2021-2-245-252.

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Background. In recent years there is a tendency to more often admission in our institution children with multiple IOL damage caused by laser treatment of secondary cataract operated at local hospitals.Purpose. To analyze the causes of laser damage to IOL in children underwent YAG laser destruction of secondary cataract and find best ways to prevent them.Patients and methods. We analyzed the frequency of acrylic IOL damage after YAG-laser destruction in 593 children with congenital, posttraumatic and postuveal cataract at age from 6 months to 17 years (one third of patients were less than 3 years old). All laser operations were performed on identical YAG-laser, by the same protocol and by one surgeon.Results. We confirmed that main reliable prevention factor of damage to IOL in children is the precise focus of laser beam. In past 10 years in our institution, we managed to decrease frequency of laser damage to IOL in children with secondary cataract in 4.5 times due to performing operations under general anesthesia (43.8 % in 2007–2008, 65.8 % in 2018). Thus, decreasing frequency from 5.9 % to 1.3 % in the same age group of patients.Conclusion. To achieve the effective prevention of laser damage to IOL in cases of YAG laser destruction of secondary cataract it is essential to use general anesthesia in following conditions: children 5 or below age, non-contact children of older age, children with nystagmus, CNS pathology, psychomotor development delay. It is unacceptable to perform this operations without general anesthesia in children that can’t fix the gaze. Furthermore it is important to use contact lenses to fix the eyes of a child, select the individual less invasive method and technique of laser operation, utilize single short impulses with minimal effective energy, thoroughly follow standard safe energy modes (impulse energy shouldn’t be more than 2.4 mJ, impulse number should be not more than 100).
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Nalisko, Mykola, Valerii Sobolev, Dmytro Rudakov, and Nataliia Bilan. "Assessing safety conditions in underground excavations after a methane-air mixture explosion." E3S Web of Conferences 123 (2019): 01008. http://dx.doi.org/10.1051/e3sconf/201912301008.

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A technique for evaluation of shock wave impulse after a methane-air mixture explosion is elaborated. The numerical model developed in previous studies has been verified in the laboratory by using laser initiation of explosives and measuring the pressure impulses of explosion products on a ballistic pendulum. To evaluate the mechanical impulse the functional correlations between its magnitude, the swing angle, and the pendulum characteristics have been derived analytically. The reliability of experimental results is ensured by calibrating the sensor that measures the pendulum swing angle and estimating the impulse measurement errors caused by specifics of angle measurements by a digital voltmeter, pendulum axis friction, and the pauses between measurements. Testing the developed technique to evaluate the shock wave impact showed satisfactory consistency of experimental and theoretical results with the momentum deviation below 9%, which confirms model applicability and correct reproducibility of the shock wave propagation process.
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Sęk, Piotr, and Szymon Tofil. "Laser Cold Ablation as a Cutting Edge Method of Forming Silicon Wafers Used in Solar Cells." Advanced Materials Research 874 (January 2014): 113–18. http://dx.doi.org/10.4028/www.scientific.net/amr.874.113.

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The article shows experimental results of mild cutting of surface layers of polycrystalline silicon photovoltaic cells with a picoseconds UV laser. Current technology makes a strong point on reliability and quality of photovoltaic microprocessing. Using short impulse lasers guarantee best quality of cutting edge without burr, HAZ and changing crystalline structure of the base material, with is very important due to electrical conductivity of the solar cell.
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Phipps, Claude. "Lisk-Broom: A laser concept for clearing space debris." Laser and Particle Beams 13, no. 1 (March 1995): 33–41. http://dx.doi.org/10.1017/s0263034600008831.

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So-called “space junk” forced a change of plan for a recent Shuttle mission. However, ground-based lasers with atmospheric-turbulence-compensating beam directors represent a singularly effective method of de-orbiting space junk, because they use cheap Earth-based power, and because they lend themselves to rapid retargeting. Plasma physics and lasertarget interaction theory dictate the laser parameters for a particular mission. We will discuss a practical laser system and beam director with 20-kW average power at 0.5-µm wavelength that is capable of clearing most low-Earth-orbit objects with mass less than 100 kg in about 4 years. This is a special application of the Laser Impulse Space Propulsion (LISP) concept, by which objects are propelled in space by the ablation jet produced on their surface by a remote laser.
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Yin, Gui Min, Zhan Guo Li, and Meng Li. "The Optimization Study about Technological Parameters of YAG Laser Precision Cutting Stainless Sheet." Advanced Materials Research 652-654 (January 2013): 2369–73. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.2369.

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Using high power Nd3+:YAG pulse laser for precision cutting stainless sheet, study the effects of the laser cutting technological parameters on quality of cutting surface and joint-cutting width. The data of single factor experiment proved： With the increasing of scanning velocity, the joint-cutting width decreased; the width increased with the increasing of scanning velocity, laser current, impulse frequency and impulse width; the increasing of impulse frequency may improve the processing quality and ultimate cutting speed; the data of two-factors experiment proved: when the output power and impulse width are fixed, the impulse frequency will be increased, the joint-cutting width will be decreased; when the output power and impulse frequency are fixed, the impulse width will be increased, the joint-cutting width will be decreased.
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Linkevičius, Linas. "Membership of NATO is the Impulse for Reforms." Lithuanian Annual Strategic Review 1, no. 1 (July 18, 2003): 7–15. http://dx.doi.org/10.47459/lasr.2003.1.1.

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Ye, Ji Fei, Guang Yu Wang, and Dian Kai Wang. "Measurement of Laser Ablation Micro Impulse Using the Torsion Pendulum Interferometry." Advanced Materials Research 301-303 (July 2011): 1078–82. http://dx.doi.org/10.4028/www.scientific.net/amr.301-303.1078.

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A method is described for measuring the micro impulse induced by the laser ablation. This method is based upon the torsion pendulum interferometry technique. The method measures the micro impulse through the detection of the swinging angle of torsion pendulum. The swinging angle is obtained by the laser differential interferometry. For the 10-4~10-7 magnitude micro-impulse, It could be the important measurement method in the research of micro laser plasma thruster (mLPT). The results of some preliminary experiments are presented with detailed reference to experiment methodology and accuracy. The measurement technique is well suited to cases seeking the measurement of mN×s magnitude micro-impulse.
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Dissertations / Theses on the topic "Impulsi laser"

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Empironi, Andrea. "Lavorazione laser ad impulsi di materiali metallici sottili alto-riflettenti: analisi di fattibilità." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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All’interno del presente elaborato di tesi viene condotto uno studio di fattibilità riguardante la realizzazione di giunti saldati per trasparenza di spessori sottili di Alluminio su Rame. Il processo di saldatura laser di materiali dissimili alto-riflettenti, come quelli in esame, presenta le seguenti problematiche principali: lo scarso assorbimento del fascio laser da parte di entrambi i metalli, la presenza di difetti di saldatura quali cricche, insellamenti del cordone, porosità e la possibile formazione di intermetallici fragili. Tutte le prove sperimentali sono state realizzate grazie ad una macchina di saldatura laser che emette il fascio in regime impulsato (con impulsi della durata compresa tra 12 e 500 ns), alla lunghezza d’onda di 1064 nm. Testando gli effetti di ogni forma d’onda a disposizione, in combinazione con differenti velocità d’avanzamento del fascio su entrambi i materiali, viene portata a termine la caratterizzazione sperimentale della macchina e, in seguito, il focus si sposta sull’analisi dei giunti saldati. In primo luogo, vengono messi in mostra i risultati ottenibili tramite saldatura lineare e, successivamente, viene analizzata la tecnica di saldatura wobbling con ampiezza circolare pari a 0,1 mm, la quale ha condotto alla realizzazione dei giunti migliori. A seguito di vari set di prove sperimentali, sono state individuate due possibili finestre operative, ciascuna contraddistinta da determinati parametri di processo individuati come ottimali. È stata effettuata una prima caratterizzazione meccanica dei giunti qualitativamente migliori tramite prove di microdurezza Vickers con carico pari a 0,1 kg. In conclusione, vengono approfonditi i risultati ottenuti grazie ai parametri di processo individuati e vengono presi in considerazione eventuali sviluppi futuri, come la realizzazione di cordoni dalla forma a spirale.
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Tani, Silvio. "Applicabilità di sorgenti laser ad impulsi lunghi nella saldatura di ottone." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016.

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Nella seguente tesi viene affrontato il problema dell'applicabilità di sorgenti laser nella saldatura dell'ottone; questo materiale risulta difficile da saldare poiché nella lega è presente lo zinco, un elemento altamente volatile. La presenza dello zinco comporta la realizzazione di cordoni di saldatura non ottimali, caratterizzati da inclusioni e porosità. Nell'elaborato viene prima descritto il laser con le sue applicazioni industriali; poi seguono in ordine una descrizione del laser Nd:YAG, una panoramica sull'ottone OT 63 (CuZn37) trattato ed una descrizione dettagliata sul sistema laser usato per le prove in laboratorio (sistema SISMA SWA-300). Infine viene trattata in maniera molto approfondita la parte relativa alle prove effettuate sull'ottone, mettendo in evidenza i parametri usati e commentando i risultati ottenuti, in modo da avere un'idea circa l'effettiva applicabilità dei processi di saldatura laser sul materiale in oggetto.
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Carughi, Giovanni. "Lavorazioni laser ad impulsi di materiali metallici sottili alto riflettenti: analisi dei risultati." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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Gli spiccati vantaggi di adottare fasci laser per la saldatura di componenti elettrici estremamente sensibili ad alterazioni termiche sono visti con molto interesse da sempre più aziende, soprattutto appartenenti al mondo dell’automotive dove l’elettrificazione nei prossimi anni farà da padrona e risulta necessario trovare processi performanti per effettuare giunzioni solide e con elevate caratteristiche meccaniche ed elettriche delle celle per l’accumulo di energia elettrica.
Diversi studi hanno già portato ad ottenere buone saldature di spessori sottili di rame e alluminio con laser di elevata potenza di tipo continuo, la saldatura di questi materiali con laser di tipo impulsato invece risulta ancora tutta da esplorare e ad oggi sono poche le macchine in commercio che permettono di eseguire tali lavorazioni e le ricerche scientifiche a riguardo. L’elaborato contiene tutti i passaggi logici e i risultati ottenuti in termini di profondità di penetrazione e larghezza di interfaccia dei cordoni che sono stati rilevati durante la ricerca dei parametri di lavorazione ideali per ottenere giunzioni per trasparenza di rame su alluminio con elevate resistenze meccaniche, basse resistenza elettriche e ridotte porosità ed imperfezioni. Le prove sono state effettuate utilizzando una sorgente laser in fibra Yb da 100 W ad impulsi dell’ordine dei nanosecondi.
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Michau, Vincent. "Conversion de fréquence et compression d'impulsion d'un laser alexandrite par diffusion Raman stimulée intracavité." Paris 11, 1988. http://www.theses.fr/1988PA112065.

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Un système laser alexandrite de forte puissance a été mis au point. Il délivre une impulsion de 500 mj en énergie sur une plage d'accord de 60 nm à la cadence de 4 Hz. Ce développement a été accompagnée d'une étude générale de la possibilité d'accord en fréquence des cavités en anneau associées a des milieux présentant du gain en bande large. Un dispositif de diffusion Raman stimulée intracavité permettant de déplacer la plage d'accord de l'alexandrite vers l'infrarouge a été modélisé sur microordinateur et testé expérimentalement. Un rendement quantique de conversion de 40% a ainsi été obtenu. Par ailleurs, la technique de compression temporelle d'impulsion par diffusion Raman stimulée intracavité a été appliquée au laser alexandrite: taux de compression de 5
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Sasoh, Akihiro, Koichi Mori, Kohei Anju, Koji Suzuki, Masaya Shimono, and Keisuke Sawada. "Diagnostics and Impulse Performance of Laser-Ablative Propulsion." American Institite of Physics, 2008. http://hdl.handle.net/2237/12005.

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Simoncig, Alberto. "The role of the electron recoiling mechanism in coherent light high-order harmonics generation: from the source to the applications." Doctoral thesis, Università degli studi di Trieste, 2010. http://hdl.handle.net/10077/3581.

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2008/2009
I processi di generazione di armoniche di ordine superiore (High-order Harmonic Generation o HHG) in gas inerti rappresentano, attualmente, la tecnica piu` promettente per la creazione di impulsi di luce coerente nell'estremo ultra-violetto (EUV) in una configurazione table-top. I processi HHG si basano sull'interazione non-lineare, tra impulsi laser ultra-corti, tipicamente dell'ordine della decina di femtosecondi, e atomi di gas inerti. Le caratteristiche che distinguono i processi HHG sono la loro durata temporale, che puo` essere nel dominio degli attosecondo e il fatto che l'interazione e` non perturbativa. Invece, la natura quantistica dei processi HHG implica la presenza di meccanismi di diffusione che influenzano la funzione d'onda dell'elettrone atomico coinvolto nell'interazione con il campo laser. Il ruolo della diffusione viene usualmente trascurato nella letteratura corrente, sebbene quest'ultima sia strettamente legata al controllo dell'efficienza del processo HHG e dello stato di polarizzazione dei fotoni generati. Il lavoro di tesi e` focalizzato sullo studio sperimentale e teorico/fenomenologico del ruolo dei meccanismi di diffusione, e sul loro controllo, al fine di incrementare l'efficienza e la qualita` ottica, i.e. coerenza, struttura temporale, etc., dei fotoni HHG prodotti. Gli studi e gli esperimenti condotti forniscono, in base alla nostra attuale conoscenza, la prima dimostrazione quantitativa a supporto del modello di Leweinstein. Accanto alla caratterizzazione spettrale, viene presentato uno studio accurato circa le condizioni minime necessarie a generare impulsi HHG, sempre legate al ruolo della diffusione della funzione d'onda elettronica. I risultati hanno permesso di ottenere una piu` profonda comprensione della complessa dinamica non-lineare, che sta alla base dei processi HHG. Accanto allo studio della diffusione si e` cercato di ottenere il controllo sullo stato di polarizzazione degli impulsi HHG, i quali mantengono la polarizzazione della radiazione laser utilizzata. La stessa diffusione impedisce di creare efficientemente armoniche di ordine superiore con polarizzazione ellittica (o circolare). Per risovere questo problema e` stata abbiamo sviluppato una collaborazione con il gruppo CXRO del Lawrence Berkeley National Laboratory, (Berkeley, USA), grazie al quale sono state realizzate una serie di ottiche multistrati innovative basate sul principio dell'angolo di Brewster, e disegnate appositamente per polarizzare circolarmente impulsi di luce EUV. Queste ultime sono state preliminarmente testate con successo sulla beam-line 6.3.2 del sincrotrone di Berkeley. La parte finale della tesi presenta la prima sorgente di impulsi HHG, polarizzati circolarmente utilizzando i citati multistrati. Per verificare l'efficienza e` di questi multistrati e` stato condotto un esperimento di dicroismo magnetico circolare con radiazioni EUV (EUV-MCD), unico nel sul genere, in quanto utilizza gli impulsi HHG polarizzati circolarmente per sondare il comportamento dicroico in corrispondenza delle soglie di assorbimento M di metalli ferromagnetici come Fe e Ni o delle loro leghe. Il fine ultimo e` dato dalla realizzazione di un esperimento risolto in tempo capace di utlizzare impulsi HHG circolarmente polarizzati per comprendere il processo di demagnetizzazione di sistemi ferromagnetici, sulla scala temporale del femtosecondo.
XXII Ciclo
1982
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Delahaye, Hugo. "Lasers femtosecondes SWIR-MIR à fibres optiques pour la génération de rayonnements secondaires de l’EUV au MIR." Thesis, Limoges, 2020. http://www.theses.fr/2020LIMO0064.

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L’interaction entre l’auto-modulation de phase de phase et la dispersion temporelle permet l’installation du régime solitonique, solution de l’équation de Schrödinger en régime non linéaire. Dans le cas d’impulsion subpicoseconde emplissant la condition d’existence du soliton fondamental, leur large spectre les expose à la dispersion d’ordre 3 et la susceptibilité Raman. L’interaction de ses phénomènes mène à l’auto-décalage de soliton. La fission solitonique et l’auto-décalage de soliton permettent la génération d’impulsion proche 100 fs accordables en longueur d’onde. La problématique de la thèse se résume à l’utilisation de ce phénomène pour développer des systèmes à fortes puissances crêtes à des longueurs d’ondes, entre 2 et 3μm,non couvertes par les lasers de type MOPA et MOFA. Le design de fibres à large aire modale a été nécessaire afin de réaliser des sources à fortes puissances crêtes dans la bande de transparence de la silice. L’étude des différentes fibres transparente dans le moyen infrarouge a été nécessaire ainsi que leur intégration dans un système MOFA pour la réalisation de source dans la gamme [2,4;3] μm.La maitrise des propriétés du régime solitonique a permis de génération des impulsions de puissance crête proche et supérieure au MW dans des fibres souples à cœur plein (0,8MW à 1,7μm et 2,8MW à 2,2μm); ainsi que, la génération de soliton via un laser monolithique à des longueurs d’ondes peu couvertes >2,4 μm avec des puissances crêtes non égalées (35kW à 2,75μm, 9kW à 3,01μm)
The interaction between selfphase modulation and chromaticdispersion allows the installation of the solitonic regime, a solution of Schrödinger's equation in non-linear regime. In the case of subpicosecond impulses filling the condition of existence of the fundamental soliton, their largespectral bandwidth exposes them to 3rd order dispersion and Raman susceptibility. The interaction of these phenomena leads to soliton self-frequency shift. Solitonic fission and soliton self-frequency shift allow the generation of near 100 fs tunable wavelength pulses. The problem of the thesis can be summarized by the use of this phenomenon to develop high peak power sourcesat wavelengths, between 2 and 3 μm, not covered by MOPA and MOFA lasers. The design of fibres with a large modal area was necessary in order to achieve high peak power sources in the transparency band of silica. The study of the different fibres transparent in the mid-infrared was necessary as well as their integration in a MOFA sourcefor the conceptionof sources in the range [2,4;3] μm. The mastery of the solitonic regime properties allowedusthe generation of pulses of peak power close to and above MWin flexible fibres with a solid core (0.8MW to 1.7μm and 2.8MW to 2.2μm). Another result wasthe generation of soliton via a monolithic laser at wavelengths poorly covered>2.4 μm with peak powers (35kW to 2.75μm, 9kW to 3.01μm)
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Miranda, Miguel Nicolau da Costa Ribeiro de. "Amplificação óptica de impulsos laser ultra-curtos." Master's thesis, Porto : edição do autor, 2006. http://hdl.handle.net/10216/64091.

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Miranda, Miguel Nicolau da Costa Ribeiro de. "Amplificação óptica de impulsos laser ultra-curtos." Dissertação, Porto : edição do autor, 2006. http://catalogo.up.pt/F?func=find-b&local_base=FCB01&find_code=SYS&request=000089810.

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Adamonis, Jonas. "High power Nd:YAG laser for pumping of OPCPA systems." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093516-33211.

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This thesis was aimed to develop, investigate and optimize high power Nd:YAG laser system for OPCPA (Optical Parametric Chirped Pulse Amplifiers) pump. The particular attention is paid for the temporal characteristics of the Nd:YAG amplifies output pulse. Employment of Fabry-Perоt etalons in the cavities of two-stage Nd:YAG regenerative amplifier enables for amplified pulse stretching from 60 fs to ~ 100 ps pulse widths. The modulation of amplified pulse envelope is minimal when ration of thickness of the etalons is around 2. Envelope modulation can be controlled by changing the reflectivity of etalons. In order to improve amplified pulse contrast, we for the first time to our knowledge implemented second order intensity dependent filter, based on the effect of fundamental pulse polarization rotation in unbalanced second harmonic generators. By using this method, the contrast of the output pulses was improved by >102 times. We also demonstrated that Gaussian pulses from the output of Nd: YAG amplifiers can be transformed into flat–top pulses by using cascade second harmonic generation processes. The developed high output energy Nd:YAG amplifiers system for OPCPA pumping is optically synchronized with pulses of Yb:KGW oscillator and features two 532 nm outputs with pulse parameters: a) Gaussian pulse profile, ~ 300 mJ energy, 75 ps pulsewidth; b) hiper- Gaussian pulse profile, ~100 mJ energy, pulse width 100-150 ps.
Disertacija yra skirta sukurti, ištirti ir optimizuoti didelės galios Nd: YAG lazerių sistemą efektyviam moduliuotos fazės signalų optinių parametrinių stiprintuvų kaupinimui. Ypatingas dėmesys yra skiriamas Nd:YAG stiprintuvų išvadinių impulsų laikinių parametrų formavimui. Pademonstravome, kad Fabry-Pero interferometrų panaudojimas Nd:YAG dvipakopio regeneracinio stiprintuvo rezonatoriuose leidžia stiprinamų impulsų trukmę padidinti nuo ~ 60 fs iki 100 ps. Tuo tarpu išvadinių impulsų laikinės plėtros mastas bei gaubtinės moduliacijos gylis gali būti valdomas keičiant etalonų atspindžio koeficientą, o jų gaubtinės moduliacijos vertė mažiausia, kai etalonų storio santykis artimas 2. Sustiprintų impulsų kontrasto gerinimui pirmą kartą pritaikėme netiesinį antros eilės filtrą, veikiantį fundamentinės spinduliuotės poliarizacijos sukimo, išderintame antros harmonikos generatoriuje, efekto pagrindu. Tokiu būdu Nd:YAG stiprintuvuose sustiprintų impulsų kontrasto vertė pagerinta apie 102 kartų. Taip pat pademonstruota, kad Nd: YAG stiprinimo sistemos išėjime naudojant pakopinius antros harmonikos generacijos procesus, Gauso formos impulsus galima transformuoti į hipergauso impulsus. Sukurta didelės išvadinės energijos pikosekundinė Nd:YAG stiprintuvų sistema yra optiškai sinchronizuota su užduodančio femtosekundinio Yb:KGW osciliatoriaus impulsais ir turi ~ 300 mJ , 75 ps trukmės Gauso impulsų bei 100 mJ, > 100 ps trukmės hipergauso laikinės formos impulsų išvadus.
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Books on the topic "Impulsi laser"

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Herrmann, Joachim. Lasers for ultrashort light impulses. Amsterdam: North-Holland, 1987.

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UWBUSIS 2006 (2006 Sevastopolʹ, Ukraine). The third international conference, ultrawideband and ultrashort impulse signals: UWBUSIS 2006, September 19-22, 2004, Sevastopol, Ukraine. Piscataway, NJ: IEEE, 2006.

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International Conference on Ultrawideband and Ultrashort Impulse Signals (4th 2008 Sevastopolʹ ,Ukraine). 2008 4th International Conference on Ultrawideband and Ultrasho[r]t Impulse Signals: UWBUSIS 2008 : September 15-19, 2008, Sevastopol, Ukraine. [United States]: IEEE, 2008.

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International Workshop on Ultrawideband and Ultrashort Impulse Signals (2nd 2004 Sevastpol, Ukraine). UWBUSIS 2004: 2004 Second International Workshop [on] Ultrawideband and Ultrashort Impulse Signals : September 19-22, 2004, Sevastopol, Ukraine. Piscataway, NJ: IEEE, 2004.

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Marciak-Kozlowska, Janina, and Miroslaw Kozlowski. Fundamentos da interacção dos impulsos laser com a matéria. Sciencia Scripts, 2020.

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Institute of Electrical and Electronics. Uwbusis 2004: 2004 Second International Workshop [On] Ultrawideband and Ultrashort Impulse Signals: September 19-22, 2004, Sevastopo. Institute of Electrical & Electronics Enginee, 2004.

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Hammond, Christopher J., Marc N. Potenza, and Linda C. Mayes. Development of Impulse Control, Inhibition, and Self-Regulatory Behaviors in Normative Populations across the Lifespan. Edited by Jon E. Grant and Marc N. Potenza. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780195389715.013.0082.

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Impulsivity represents a complex multidimensional construct that may change across the lifespan and is associated with numerous neuropsychiatric disorders including substance use disorders, conduct disorder/antisocial personality disorder, and traumatic brain injury. Multiple psychological theories have considered impulsivity and the development of impulse control, inhibition, and self-regulatory behaviors during childhood. Some psychoanalytic theorists have viewed impulse control and self-regulatory behaviors as developing ego functions emerging in the context of id-based impulses and inhibitory pressures from the superego. Object relationists added to this framework but placed more emphasis on mother–child dyadic relationships and the process of separation and individuation within the infant. Cognitive and developmental theorists have viewed impulse control and self-regulation as a series of additive cognitive functions emerging at different temporal points during childhood and with an emphasis on attentional systems and the ability to inhibit a prepotent response. Commonalities exist across all of these developmental theories, and they all are consistent with the idea that the development of impulse control appears cumulative and emergent in early life, with the age range of 24–36 months being a formative period. Impulsivity is part of normal development in the healthy child, and emerging empirical data on normative populations (as measured by neuropsychological testing batteries, self-report measures, and behavioral observation) suggest that impulse control, self-regulation, and other impulsivity-related phenomena may follow different temporal trajectories, with impulsivity decreasing linearly over time and sensation seeking and reward responsiveness following an inverted U-shaped trajectory across the lifespan. These different trajectories coincide with developmental brain changes, including early maturation of subcortical regions in relation to the later maturation of the frontal lobes, and may underlie the frequent risk-taking behavior often observed during adolescence.
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Richardson, Amanda. Gender and Space in the Later Middle Ages Past, Present, and Future Routes. Edited by Christopher Gerrard and Alejandra Gutiérrez. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780198744719.013.33.

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This article traces approaches to social space back to the 1950s and the subsequent pursuit of the ‘rise of privacy’. It then delivers a historiography of late medieval gender and space since the 1990s under three main themes: sacred spaces (churches, nunneries, and monasteries), vernacular architecture, and high-status residences including gardens and deer parks. It is noted that from the mid-1990s the impulse to make women ‘visible’ was largely replaced by an emphasis on differences—and similarities—among and between women, men, and other social categories and contexts, such as urban and rural, and that recent studies have moved on to explore the transgression of gendered boundaries. Methodologies such as access analysis are discussed and suggestions are made for future research, including the opportunities afforded by GIS.
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Food and drink - February 2000: Bottled lager, cake bars and cereal bars, dashboard dining, frozen desserts, impulse ice cream. London: Mintel International Group, 2000.

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Turner, Martin R., Matthew C. Kiernan, and Kevin Talbot. Technical advances in neuroscience. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199658602.003.0001.

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This chapter highlights key technological advances in neuroimaging, the understanding of impulse transmission, and the molecular biology of the nervous system that have underpinned our modern understanding of the brain, mind, and nervous system. Neuroimaging spans the sub-cellular and systems levels of neuroscience, beginning with electron microscopy and then, 50 years later, magnetic resonance imaging and increasingly sophisticated mathematical modelling of brain function. These developments have been interleaved with the improved understanding of neurotransmission, starting with the seminal observations made from giant squid axon recordings, which were translated into clinically useable tools through the application of electric current, and later with magnetic stimulation. It is during the last 50 years that a molecular framework for these concepts emerged, with the cloning of genes that began in Duchenne muscular dystrophy, paving the way for the wider human genome project.
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Book chapters on the topic "Impulsi laser"

1

Memišević, Lejla. "Von einem Lager ins nächste." In Kosmopolitische Impulse, 65–67. Vienna: Springer Vienna, 2010. http://dx.doi.org/10.1007/978-3-211-99152-7_9.

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Fritz, H. M. "PIV applied to landslide generated impulse waves." In Laser Techniques for Fluid Mechanics, 305–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-662-08263-8_18.

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Its, Alexander R., and Victor Yu Novokshenov. "The dynamics of electromagnetic impulse in a long laser amplifier." In Lecture Notes in Mathematics, 205–11. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/bfb0076675.

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Yu, X. L., T. Ohtani, A. Sasoh, S. Kim, N. Urabe, and I. S. Jeung. "Impulse characteristics of laser-induced blast wave in monoatomic gases." In Shock Waves, 979–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/978-3-540-27009-6_149.

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Echim, Marius M., and Joseph Lemaire. "The impulsive penetration mechanism: Advances in the numerical and experimental verification." In Earth's Low-Latitude Boundary Layer, 169–77. Washington, D. C.: American Geophysical Union, 2003. http://dx.doi.org/10.1029/133gm17.

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Xie, Xinhua, Katharina Doblhoff-Dier, Huailiang Xu, Stefan Roither, Markus Schöffler, Daniil Kartashov, Sonia Erattupuzha, et al. "Controlling Fragmentation Reactions of Polyatomic Molecules with Impulsive Laser Alignment." In Springer Proceedings in Physics, 138–42. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13242-6_33.

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Kobayashi, Takayoshi. "Photo-Impulsive Reactions in the Electronic Ground State without Electronic Excitation." In Ultrashort Pulse Lasers and Ultrafast Phenomena, 567–75. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9780429196577-78.

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Kumaran, V., A. Vanav Kumar, and J. Sarat Chandra Babu. "Impulsive Boundary Layer Flow Past a Permeable Quadratically Stretching Sheet." In Nonlinear Science and Complexity, 191–98. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-90-481-9884-9_24.

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Iwakawa, A., Z. Wang, H. Tsuruta, T. Shoda, B. Wang, and A. Sasoh. "Effects of Negative Overpressure Phase of a Laser Breakdown-Induced Blast Wave on Impulse Characteristics." In 30th International Symposium on Shock Waves 2, 1339–43. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44866-4_95.

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Shi, Nan, Liang Xia, and Ignas G. Niemegeers. "A Link Layer Protocol for Self-Organizing Ultra Wide Band Impulse Radio Networks." In Challenges in Ad Hoc Networking, 21–30. Boston, MA: Springer US, 2006. http://dx.doi.org/10.1007/0-387-31173-4_3.

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Conference papers on the topic "Impulsi laser"

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Ping, Zhu, Liya Hou, and Weiyi Zhang. "The Measurement on Micro-Jet Impulse Based on Laser Interferometer." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78030.

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In the paper the heterodyne laser vibrometer combined with torsion pendulum system is employed to measure contactless the oscillating velocity of the horizontal target struck by pulse hydrone micro-jet in the experimental platform, which has the feature of measuring precisely impulse (measurement error ≤ 0.618%). The oscillating velocities of pulse micro-jet from converging-diverging, converging and cylindrical nozzles striking on horizontal target are measured respectively in normal atmosphere, and the values of the impulses are calculated by employing the dynamic character equation of force acted by pulse micro-jet. The result of experiment show that the impulse of converging nozzle with the ratio of sectional area of exit to that of inlet (Aexit/Ainlet) being 0.1 is 65% of that of cylindrical nozzle, and is 26.8% of that of converging-diverging nozzle with the ratio of sectional area of throat to that of inlet (Athroat/Ainlet) being 0.1145. Converging-diverging nozzle has obvious gaining on the impulse of hydrone propellant.
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Morgan, Michael A. "Scale model ultrawideband impulse radar." In OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, edited by Roger S. Vickers. SPIE, 1993. http://dx.doi.org/10.1117/12.145528.

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Evans, John A., Mojtaba Oghbaei, and Kurt S. Anderson. "Modeling and Simulation of a Laser-Powered Lightcraft Using Advanced Simulation Tools." In ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84465.

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This paper outlines efforts toward implementation of a new state-time methodology for dynamic simulation of a six-degree of freedom (6-DOF) model of the Type 200 laser-powered lightcraft. The lightcraft problem is a well-suited application demonstrating the potential advantage of using the state-time formulation as the craft’s temporal domain is much larger than its spatial domain. Indeed, while relatively few processors can be effectively utilized in modeling the vehicle via traditional state-type algorithms, more than 105 processors may be potentially exploited in a state-time dynamic simulation. In this paper, a modified state-time methodology is derived in order to account for impulsive characteristics. This impulsive formulation allows for parallelization not only between impulses but also across impulses. Furthermore, an aerodynamic model fully compatible with the state-time formulation is presented. Validation of the proposed method is obtained by comparing the state-time simulation results with the results of a traditional state-type dynamics algorithm using Autolev software.
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Venna, Suresh V., and Y. J. Lin. "PZT-Actuated In-Flight Deicing With Simultaneous Shear and Impulse Forces." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-61554.

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Piezoelectric actuations for simultaneous generation of shear and impulse forces for effective and energy efficient deicing applications are proposed. Aircraft leading edge structures is considered for the analysis. Adhesive shear bond between the ice layer and the substrate, which is more than ten times weaker than the normal bond, is targeted to achieve deicing. Piezoelectric actuators consisting of high normal to shear coupling factor(d15) are considered at the inner surface of the leading edge at the locations where highest amount of ice accretion is occurred. Simultaneous shear and impulse force generation can be achieved with actuators consisting of two sets of electrodes, one arranged in parallel to the poling direction and the other perpendicular to the poling direction to generate shear forces and normal forces respectively. Appropriate piezoelectric material configuration is chosen, so that enough shear forces are generated to weaken the bond of the ice-substrate interface which is weak in shear. Once the shear bond is weakened, applied normal impulses force the ice layer come off the surface. Finite element model of the leading edge structure with ice accretion layer and piezoelectric actuators are constructed. Simulations of the deicing process are performed and the actuator locations, electric charge applied and impulse duration are optimized. This method employs single actuator for both shear and impulse generation and consumes far less power than any existing in-flight deicing methods.
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Ralston, James M. "System analysis of ultrawideband instrumentation radars: impulse versus stepped-chirp approaches." In OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, edited by Roger S. Vickers. SPIE, 1993. http://dx.doi.org/10.1117/12.145520.

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Rosen, D. I., C. J. Rollins, and M. Gauthier. "Experimental studies in ground to orbit laser propulsion." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.tuz6.

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Experiments have been conducted in support of a program to develop ground to orbit laser propulsion.1 Optical diagnostics provide temporally and spatially resolved measurements of temperature, opacity, and electron density in laser-induced plasmas for various candidate propellants. Plasma ignition thresholds are determined spectroscopically. Mass loss and impulse coupling measurements have been obtained for various propellants in irradiance regimes appropriate to double-pulse detonation wave rockets driven by a ground-based repetitively pulsed IR laser. Experiments have used two 10-J CO2 TEA lasers. Plans for tests at up to 2 kJ/pulse are also discussed.
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Snyder, Wendy J., Wei-Qiang Shi, Sandor G. Vari, and Warren S. Grundfest. "Comparative study of pulsed Ho:YAG versus Tm:YAG: impulse-induced pressure in porcine aorta." In OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, edited by Steven L. Jacques and Abraham Katzir. SPIE, 1993. http://dx.doi.org/10.1117/12.147656.

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Niino, Masayuki, Viliam Kmetik, Tatsuo Kumagai, Akio Moro, Seishiro Kibe, and Kazuo Imasaki. "Impulse generated from laser targets." In Advanced High-Power Lasers and Applications, edited by Claude R. Phipps and Masayuki Niino. SPIE, 2000. http://dx.doi.org/10.1117/12.376983.

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Sasoh, Akihiro, Toshihiro Ogawa, Sukyum Kim, Takehiro Kawahara, In-Seuck Jeung, Xilong Yu, and Toshiro Ohtani. "Laser Impulse Generation in Flight." In 42nd AIAA Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2004. http://dx.doi.org/10.2514/6.2004-650.

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Schall, Wolfgang O., Hans-Albert Eckel, Wilhelm Mayerhofer, Wolfgang Riede, and Eberhard Zeyfang. "Comparative lightcraft impulse measurements." In International Symposium on High-Power Laser Ablation 2002, edited by Claude R. Phipps. SPIE, 2002. http://dx.doi.org/10.1117/12.482046.

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Reports on the topic "Impulsi laser"

1

Fournier, K. Investigation of Laser Coupling for Impulse Generation. Office of Scientific and Technical Information (OSTI), August 2012. http://dx.doi.org/10.2172/1053689.

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McKay, J. A., and P. M. Laufer. Survey of Laser-Produced Pressure and Impulse Data. Fort Belvoir, VA: Defense Technical Information Center, January 1988. http://dx.doi.org/10.21236/ada197313.

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Hayes, S., and S. Novell. Direct Laser Impulse (DLI) System Alignment Requirements Engineering Project. Office of Scientific and Technical Information (OSTI), June 2022. http://dx.doi.org/10.2172/1875226.

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D'Souza, Brian, and Andrew Ketsdever. Direct Impulse Measurements of Ablation Processes from Laser-Surface Interactions. Fort Belvoir, VA: Defense Technical Information Center, May 2005. http://dx.doi.org/10.21236/ada435844.

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Dahlbacka, G. 2 dimensional analysis of a NOVETTE laser generated stress-impulse experiment. Office of Scientific and Technical Information (OSTI), October 1988. http://dx.doi.org/10.2172/6159373.

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Townsend, J. K., William M. Lovelace, and Arjun Bharadwaj. Medium Access and Data Link Layer Protocols for Impulse Radio: Covertness, Timing, and Chip Discrimination. Fort Belvoir, VA: Defense Technical Information Center, March 2003. http://dx.doi.org/10.21236/ada416018.

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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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