Interconnect capacitance extraction under geometric uncertainties

Interconnects are an important constituent of any large scale integrated circuit, and accurate interconnect analysis is essential not only for post-layout verification but also for synthesis. For instance, extraction of interconnect capacitance is needed for the prediction of interconnect-induced delay, crosstalk, and other signal distortion related effects that are used to guide IC routing and floor planning. The continuous progress of semiconductor technology is leading ICs to the era of 45 nm technology and beyond. However, this progress has been associated with increasing variability during the manufacturing processes. This variability leads to stochastic variations in geometric and material parameters and has a significant impact on interconnect capacitance. It is therefore important to be able to quantify the effect of such process induced variations on interconnect capacitance. In this thesis, we have worked on a methodology towards modeling of interconnect capacitance in the presence of geometric uncertainties. More specifically, a methodology is proposed for the finite element solution of Laplace's equation for the calculation of the per-unit-length capacitance matrix of a multi-conductor interconnect structure embedded in a multi-layered insulating substrate and in the presence of statistical variation in conductor and substrate geometry. The proposed method is founded on the idea of defining a single, mean geometry, which is subsequently used with a single finite element discretization, to extract the statistics of the interconnect capacitance in an expedient fashion. We demonstrate the accuracy and efficiency of our method through its application to the extraction of capacitances in some representative geometries for IC interconnects

Structural Behaviour of Steel Fiber Reinforced Concrete Composite under Blast Loading

Fibre-reinforced concrete with its higher ductility and enhanced flexural behaviour shows better performance under blast and impact loading than conventional reinforced concrete. During impulsive loadings such as blast and impact, the structural response is to absorb large amounts of energy within a short period. This article proposes the structural responses of steel Fibre reinforced concrete composite under dynamic loading for varying percentages of steel fibres. The experimental results quantitatively indicate   improvement in the performance of fiber impregnated concrete. A mathematical correlation based on empirical relations is presented as a basis function for evaluation of Fiber reinforced concrete subjected to blast/ dynamic loading. The experiments on a rectangular specimen of size 400 mm × 400 mm × 50 mm with 125gm ANFO which is equivalent to 100 gm TNT charge placed at different standoff distances, give insight of enhanced FRC behaviour. The article presents failure modes, and quantifies the elastic behaviour of FRC subjected to blast loading

Problemi umjetnog osjemenjivanja jednogrbe deve - izostanak ovulacije i zadržavanje spermija u želatinoznoj spermi.

An artificial insemination study was conducted on 17 female camels which were administered human Chorionic Gonadotrophin (hCG) to induce ovulation after confirming a follicle in the ovaries using sonography. The animals were inseminated with either diluted-cooled or fresh undiluted semen. No female camel could be impregnated with diluted and cooled semen, while pregnancy rate was low with neat undiluted semen. To ascertain possible causes of low conception rate, plasma progesterone (P4) profiles were monitored. Criteria adopted for interpretation of these profiles were as follows: P4 levels below 1 ng/ml on days 5-8 was considered to indicate failure to ovulate; a single peak of 1ng/ml on days 5-8 followed by a decline on day 12 was considered to indicate ovulation. However, failure of fertilization and P4 levels of more than 1 ng/ml on days 5-8 and day 12 followed by a decline was considered to indicate successful ovulation and fertilization, but failure of embryo survival. Consistently higher levels of P4 were considered to be indicative of pregnancy. Using these criteria, 5 of 33 inseminations were diagnosed as pregnant, while profiles of 17 of 33, 8 of 33 and 3 of 33 were indicative of failure of ovulation, failure of fertilization and failure of embryo survival, respectively. A high incidence of failure of ovulation may be due to oversized follicles or follicles in which degenerative processes might have been initiated prior to administration of hCG. High failure of fertilization may be due to a viscous form of camel semen, which may play a role as a sperm reservoir and protect the viability of spermatozoa in the female genital tract by entrapping sperm. Insemination with diluted and cooled semen may disturb the protection, resulting in failure of conception. It is concluded that the high incidence of ovulation failure and failure to deposit sperm in its natural entrapped viscous form are the major problems for development of AI in the camel. Further improvement may be expected, if we are able to standardize the appropriate insemination time around peri ovulatory time, and appropriate follicular size, which responds to hCG.Umjetno osjemenjivanje provedeno je na 17 deva kojima je dan ljudski korionski gonadotropin (hCG) u svrhu poticanja ovulacije. Prethodno je ultrazvučnom metodom ustanovljen folikul na jajnicima pretraženih deva. Deve su osjemenjene ili razrijeđenom i rashlađenom ili svježom, nerazrijeđenom spermom. Nijedna deva nije bila oplođena nakon osjemenjivanja razrijeđenom i rashlađenom spermom, a nakon osjemenjivanja nerazrijeđenom spermom stopa oplođenosti bila je niska. Radi utvrđivanja mogućih uzroka niske stope koncepcije, utvrđivana je razina progesterona u plazmi (P4). Razina P4 ispod 1 ng/ml u razdoblju 5 do 8 dana smatrala se pokazateljem izostanka ovulacije. Jednokratni porast od 1 ng/ml tijekom 5-8 dana nakon kojeg je slijedio pad 12. dana, smatrao se pokazateljem ovulacije s neuspjelom oplodnjom. P4 razine veće od 1 ng/ml tijekom razdoblja 5 do 8 dana, uključujući 12. dan nakon kojeg slijedi opadanje smatrale su se uspješnom ovulacijom i oplodnjom ali neuspjelim preživljavanjem embrija. Postojano visoke razine P4 smatrale su se pokazateljem gravidnosti. Prema navedenim kriterijima, pet od 33 osjemenjivanja rezultirala su gravidnošću. U 17 od 33 osjemenjivanja izostala je ovulacija. U 8 od 33 osjemenjivanja nije došlo do oplodnje, a u tri od 33 osjemenjnivanja embrij nije preživio. Učestala pojavnost izostanka ovulacije mogla bi se povezati s prevelikim folikulima ili folikulima u kojih su degenerativni procesi započeli prije davanja hCG. Visoka učestalost neuspjele oplodnje, mogla bi se povezati s viskoznošću sperme, zbog koje su spermiji u genitalnom traktu deve zaštićeniji i lakše preživljavaju. Osjemenjivanje s razrijeđenom i rashlađenom spermom može poremetiti navedene zaštitne mehanizme i dovesti do slabije oplođenosti. Može se zaključiti da je učestalo izostajanje ovulacije i nemogućnost polaganja sperme u njezinom prirodno viskoznom obliku glavni problem za razvoj umjetnog osjemenjivanja deva. Daljnji napredak se može očekivati ako se standardizira prikladno vrijeme osjemenjivanja (periovulatorno vrijeme), te utvrdi veličina folikula koja najbolje odgovara na aplikaciju hCG

Inflammatory Bowel Disease: Epidemiology

Inflammatory bowel disease (IBD) is characterized by two partially distinct alimentary disease processes, namely Crohn’s disease (CD) and ulcerative colitis (UC), affecting genetically predisposed individuals. CD and UC were first described in 1932 and 1859, respectively. It is estimated that 1.5 million in North America and 2.5 million persons in Europe have IBD. The peak incidence of CD and UC is between 20–30 years and 30–40 years of age, respectively. Both incidence and prevalence of CD and UC are similar across males and females. However, several studies suggest a female predominance in CD and a male predominance in UC. The pathogenesis of IBD is attributed to an uncontrolled immune-mediated inflammatory response to an unrecognized environmental trigger that interacts with the intestinal flora. Various determinants of IBD include the following: peculiar environmental triggers, intestinal immune mechanisms, heritable factors, gut flora, diet, mesenteric fat, medications, nicotine, infectious agents, immunization, hygiene, pregnancy, breastfeeding, stress and lifestyle. Predominant complications in IBD are surgery, malnutrition, disease exacerbations and cancer. Patients with CD have a higher mortality compared to general population. Epidemiological studies continue to expand our understanding of the distribution, determinants and mechanisms of IBD. This has enabled us to recognize safer and effective approaches to management

Structural Behaviour of Steel Fiber Reinforced Concrete Composite under Blast Loading

Fibre-reinforced concrete with its higher ductility and enhanced flexural behaviour shows better performance under blast and impact loading than conventional reinforced concrete. During impulsive loadings such as blast and impact, the structural response is to absorb large amounts of energy within a short period. This article proposes the structural responses of steel Fibre reinforced concrete composite under dynamic loading for varying percentages of steel fibres. The experimental results quantitatively indicate   improvement in the performance of fiber impregnated concrete. A mathematical correlation based on empirical relations is presented as a basis function for evaluation of Fiber reinforced concrete subjected to blast/ dynamic loading. The experiments on a rectangular specimen of size 400 mm × 400 mm × 50 mm with 125gm ANFO which is equivalent to 100 gm TNT charge placed at different standoff distances, give insight of enhanced FRC behaviour. The article presents failure modes, and quantifies the elastic behaviour of FRC subjected to blast loading

CNOT and Bell-state analysis in the weak-coupling cavity QED regime

We propose an interface between the spin of a photon and the spin of an electron confined in a quantum dot embedded in a microcavity operating in the weak coupling regime. This interface, based on spin selective photon reflection from the cavity, can be used to construct a CNOT gate, a multi-photon entangler and a photonic Bell-state analyzer. Finally, we analyze experimental feasibility, concluding that the schemes can be implemented with current technology.Comment: 4 pages, 2 figure

Achieving Superlubricity with 2D Transition Metal Carbides (MXenes) and MXene/Graphene Coatings

Two-dimensional (2D) materials have demonstrated unique friction and antiwear properties unmatched by their bulk (3D) counterparts. A relatively new, large and quickly growing family of two-dimensional early transition metal carbides and nitrides (MXenes) present a great potential in different applications. There is a growing interest in understanding the mechanical and tribological properties of MXenes, however, no report of MXene superlubricity in a solid lubrication process at the macroscale has been presented. Here we investigate the tribological properties of two-dimensional titanium carbide (Ti3C2) MXene deposited on SiO2-coated silicon (Si) substrates subjected to wear by sliding against a diamond-like carbon (DLC)-coated steel ball counterbody using a ball-on-disc tribometer. We have observed that a reduction of the friction coefficient to the superlubric regime (0.0067 ± 0.0017) can be achieved with Ti3C2 MXene in dry nitrogen environment. Moreover, the addition of graphene to Ti3C2 further reduced the friction by 37.3% and wear by the factor of 2 as compared to Ti3C2 alone, while the superlubricity behavior of the MXene remains unchanged. These results open up new possibilities for exploring the family of MXenes in various tribological applications

Small Amplitude Reciprocating Wear Performance of Diamond-like Carbon Films: Dependence of Film Composition and Counterface Material

Small amplitude (50 μm) reciprocating wear of hydrogen-containing diamond-like carbon (DLC) films of different compositions has been examined against silicon nitride and polymethyl-methacrylate (PMMA) counter-surfaces, and compared with the performance of an uncoated steel substrate. Three films were studied: a DLC film of conventional composition, a fluorine-containing DLC film (F-DLC), and silicon-containing DLC film. The films were deposited on steel substrates from plasmas of organic precursor gases using the Plasma Immersion Ion Implantation and Deposition (PIIID) process, which allows for the non-line-of-sight deposition of films with tailored compositions. The amplitude of the resistive frictional force during the reciprocating wear experiments was monitored in situ, and the magnitude of film damage due to wear was evaluated using optical microscopy, optical profilometry, and atomic force microscopy. Wear debris was analyzed using scanning electron microscopy and energy dispersive spectroscopy. In terms of friction, the DLC and silicon-containing DLC films performed exceptionally well, showing friction coefficients less than 0.1 for both PMMA and silicon nitride counter-surfaces. DLC and silicon-containing DLC films also showed significant reductions in transfer of PMMA compared with the uncoated steel. The softer F-DLC film performed similarly well against PMMA, but against silicon nitride, friction displayed nearly periodic variations indicative of cyclic adhesion and release of worn film material during the wear process. The results demonstrate that the PIIID films achieve the well-known advantageous performance of other DLC films, and furthermore that the film performance can be significantly affected by the addition of dopants. In addition to the well-established reduction of friction and wear that DLC films generally provide, we show here that another property, low adhesiveness with PMMA, is another significant benefit in the use of DLC films