Widestock exposure modification

A system exists for the exposure of large pieces of sensitized material. The strips are exposed, processed, and viewed by transmitted light. This procedure is used to gauge the quality of the film coating process. There are three problems with the existing system: uneven illumination, the timers do not take into account light decay, and finally, the operators, on occasion, set up the wrong conditions for an exposure. The purpose of this thesis is to modify an existing process for the automated exposure of wide stock strips. These modifications are to replace the system\u27s components with state of the art, commercially available equipment. The equipment was modified to perform the desired output as necessary. The equipment is then to be interfaced with a suitable computer and software generated to automate the system. Existing lights and timing circuits have been replaced with lighting arrangements that approximate actual end use of the products tested. Exposure control is provided by an off the shelf light integrator. An existing computer, (DEC 11/34), adapted for automation purposes was then interfaced with the new equipment to operate the system. Software is planned which will take over partial responsibility for operating the system

Lyrics and a social movement: The rhetorical influence of Bob Marley\u27s lyrics on the Rastafarian movement and universal culture

U radu je izvršena usporedba klizanja kotača dva različita skidera pri jednakim uvjetima privlačenja (jednaki tovari i nagibi traktorskog puta i šumske vlake). Prvi skider u istraživanju je ECOTRAC 120 V, hrvatskog proizvođača Hittner d.o.o. sa mehaničkom transmisijom, a drugi skider je slovenske proizvodnje WOODY 110 s hidrostatskom transmisijom. Klizanje kotača skidera tijekom istraživanja utvrđivano je na osnovu broja okretaja kotača po putu. Prijeđeni je put izračunat iz umnoška broja okretaja petoga kotača i njegovog opsega. Pri privlačenju niz nagib klizanje kotača je negativno. Općenito se može reći da se, pri istim uvjetima pri privlačenju uz nagib, klizanje kotača povećava s povećanjem težine tovara, a pri privlačenju niz nagib su manje negativne vrijednosti klizanja s povećanjem težine tovara. Klizanje kotača ovisi o težini tovara i stanju tla. Kod smrznutog tla manje je klizanje kotača. Usporedbom klizanja kotača kod istraživanih skidera ustanovljene su prednosti hidrostatsko-mehaničke transmisije pri privlačenju drva uz nagib. No, pri privlačenju niz nagib mehaničkom transmisijom su se ostvarila manja klizanja kotača. Navedeni zaključci se mogu objasniti većom krutošću mehaničke transmisije odnosno, većim unutarnjim trenjima mehaničke transmisije koji omogućavaju zadržavanje skidera pri kretanju niz nagib. S druge strane može se zaključiti o nedostatku hidrostatsko-mehaničke transmisije pri kretanju niz nagib jer vjerojatno dolazi do pada tlaka u hidrauličkom sustavu. Kod privlačenja drva uz nagib očituje se prednost hidrauličko-mehaničke transmisije uslijed učinkovitijeg prijenosa zakretnih momenata na kotače. Navedene pretpostavke potrebno je potkrijepiti daljnjim istraživanjima skidera različitih sustava transmisije pri jednakim radnim uvjetima (isto stanje podloge, uporaba lanaca i isti tovari)

Bayesian Inference of Log Determinants

The log-determinant of a kernel matrix appears in a variety of machine learning problems, ranging from determinantal point processes and generalized Markov random fields, through to the training of Gaussian processes. Exact calculation of this term is often intractable when the size of the kernel matrix exceeds a few thousand. In the spirit of probabilistic numerics, we reinterpret the problem of computing the log-determinant as a Bayesian inference problem. In particular, we combine prior knowledge in the form of bounds from matrix theory and evidence derived from stochastic trace estimation to obtain probabilistic estimates for the log-determinant and its associated uncertainty within a given computational budget. Beyond its novelty and theoretic appeal, the performance of our proposal is competitive with state-of-the-art approaches to approximating the log-determinant, while also quantifying the uncertainty due to budget-constrained evidence.Comment: 12 pages, 3 figure

Sutureless Laparoscopic Ventral Hernia Repair in Obese Patients

Results of this study show that laparoscopic ventral herniorrhaphy as an outpatient procedure without transfascial suture fixation is feasible in obese patients

Depth profiles of damage creation and hardening in MgO irradiated with GeV heavy ions

This work has been performed within the framework of the EUROfusion Enabling Research project: ENR-MFE19.ISSP-UL-02 “Advanced experimental and theoretical analysis of defect evolution and structural disordering in optical and dielectric materials for fusion applications”. The views and opinions expressed herein do not necessarily reflect those of the European Commission.The effect of irradiation with GeV heavy ions (U, Au, Bi) on the structure and mechanical properties of MgO single crystals was studied. The methods of nanoindentation, dislocation mobility, optical absorption and photoluminescence (PL) spectroscopy, X-ray diffraction and atomic force microscopy were used for damage characterization. The ion-induced increase of hardness and reduction of dislocation mobility was observed. The depth profiles of hardness, dislocation mobility and PL were investigated, and the contribution of electronic and nuclear loss mechanisms was confirmed. The efficiency of damage vs. average absorbed energy for heavy and light ions was compared. The change in the mechanism of plastic deformation at indentation was observed after severe irradiation due to the immobilization of dislocations by ion-induced extended defects. The results show that MgO single crystals maintain integrity and micro-plasticity at indentation, and exhibit improved hardness after irradiation with swift heavy ions at fluences up to 7 × 1013 ions/cm2.EUROfusion Enabling Research project: ENR-MFE19.ISSP-UL-02; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART

Signals of confinement in Green functions of SU(2) Yang-Mills theory

The vortex picture of confinement is employed to explore the signals of confinement in Yang-Mills Green functions. By using SU(2) lattice gauge theory, it has been well established that the removal of the center vortices from the lattice configurations results in the loss of confinement. The running coupling constant, the gluon and the ghost form factors are studied in Landau gauge for both cases, the full and the vortex removed theory. In the latter case, a strong suppression of the running coupling constant and the gluon form factor at low momenta is observed. At the same time, the singularity of the ghost form factor at vanishing momentum disappears. This observation establishes an intimate correlation between the ghost singularity and confinement. The result also shows that a removal of the vortices generates a theory for which Zwanziger's horizon condition for confinement is no longer satisfied.Comment: 4 pages, 4 figure

Formation of dislocations in LiF irradiated with 3He and 4He ions

Influence of the irradiation with 13.5 MeV 3He and 5 MeV 4He ions on the micro-structure and mechanical properties of LiF single crystals was studied. The depth profiles of nanoindentation, dislocation mobility, selective chemical etching and photoluminescence served for the characterization of damage. Strong ion-induced increase of hardness and decrease in dislocation mobility at the stage of track overlapping due to accumulation of dislocations and other extended defects was observed. At high fluences (1015 ions/cm2) the hardness saturates at about 3.5 GPa (twofold increase in comparison to a virgin crystal) thus confirming high efficiency of light projectiles in modifications of structure and properties. The effects of ion-induced increase of hardness and decrease of dislocation mobility are observed also beyond the ion range and possible mechanisms of such damage are discussed.This work has been supported by the Latvian national program IMIS2; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART