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Due to their high energy density, Li-ion batteries represent nowadays the most promising electrochemical storage devices for portable electronics, electric vehicles and stationary energy storage application. However, some challenges need to be overcome, especially for automotive applications. These include: the increase of the energy and power densities, decrease the cost, fast charging, safety, aging and recycling of the components, among others. A particular problem regards the sudden degradation due to the many undesired reactions which take place during battery operation. Batteries are complex systems and the effects contributing to capacity fade are still not well understood. One of these undesired reactions is the deposition of metallic lithium on the anode surface during the charging process. This phenomenon, called lithium plating, is not only the main cause for battery degradation when charging at low temperatures, but it may lead to a short circuit, when lithium dendrites deposits in a needle-like form, piercing the battery separator. In large format cells, where temperature and current distributions are not uniform, the lithium deposition process starts locally and it is difficult to detect. A few techniques have been employed to detect and quantify lithium plating, but these are not spatially resolved, and there is still no method that directly detects the deposition of metallic lithium during battery operation. Electrochemical models allow the evaluation of the lithium ions concentration, temperature and potential distribution within the cell, parameters that can be used to identify the plating onset conditions. Experimental parameterization is needed as different parameter combinations lead to the same cell potential curve. Each cell has a specific geometry and the transport parameters depend on the chemistry of the component and on the geometry of the cell. Furthermore, tabulated values for such parameters are scattered and often do not provide information on the electrode geometry. In-operando characterization techniques like optical microscopy and micro-Raman spectroscopy are employed to detect the lithium plating onset in the micro-scale. Intercalation of the plated lithium on the graphite surface was observed during the resting periods after charge and during the constant voltage step. However, at C-Rates higher than C/2 and temperatures below zero degrees, fast capacity decay due to irreversible lithium plating was observed in most commercial cells except in one type. A non-isothermal electrochemical model is used to investigate the lithium plating onset conditions of the commercial Li-ion cell where no plating was found even at very adverse conditions (1C and -10 degrees or 4C and 0 degrees). This model is parameterized experimentally and validated against the individual potentials. Geometry and transport parameters are determined at different temperatures and states of charge. New approaches for a fast parameterization process are introduced and the results are in good agreement with the ones obtained by other techniques. The model can predict well the temperature, potential and current distribution within the cell during charging at high C-rates and low temperatures. This promising model can be used to design new fast charging strategies for Li-ion batteries at low temperature without a detrimental effect on the battery life.

The Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP) has successfully operated on-orbit for nearly ten years since its launch in October 2011, continuously making global observations and improving studies of changes in the Earth’s climate and environment. VIIRS has 22 spectral bands, among which 14 are reflective solar bands (RSBs) covering a spectral range from 0.41 to 2.25 μm. The SNPP VIIRS RSBs are primarily calibrated by the onboard solar diffuser (SD), with its on-orbit degradation tracked by an onboard SD stability monitor (SDSM). The near-monthly scheduled lunar observations, together with the sensor responses over stable ground targets, have contributed to the sensor’s mission-long on-orbit calibration and characterization. Numerous improvements have been made in the RSB calibration methodology since SNPP VIIRS was launched, and the RSB calibration has reached a mature stage after almost ten years of on-orbit operation. SNPP is a joint NASA/NOAA mission and there are two teams, the NASA VIIRS Calibration Support Team (VCST) and the NOAA VIIRS Sensor Data Record Team, which are dedicated to SNPP VIIRS on-orbit calibration. In this paper, we focus on the calibration performed by the NASA VCST. The SNPP VIIRS RSB calibration methodologies used to produce the calibration coefficient look up tables for the latest NASA Level 1B Collection 2 products are reviewed and the calibration improvements incorporated in this collection are described. Recent calibration changes include the removal of image striping caused by non-uniform degradation of the SD, improvements to the method for combining lunar and SD data, mitigation of the effects due a recent anomaly in the SD measurements, estimation of the SD degradation beyond 935 nm, and fitting strategy improvements for look-up table delivery. Overall, the SNPP VIIRS RSBs have performed well since its launch and continue to meet design specifications.

Background: The objective of this study is to investigate the effectiveness of medium pressurized elastic compression stockings usage after isolated vena saphena parva stripping. Material and Methods: Between 2001 January2014 March, 60 patients (40 women, 20 men, mean age; 39± 11 years, 35 to 58 years range) treated with vena saphena parva ligation and total stripping for isolated vena saphena parva insufficiency, were enrolled in this retrospective study. Elastic bandage applied postoperatively. Patients were divided into two groups according to use of additional compression stocking for 4 weeks; as stockings using group, (group 1; 18 women, 12 men, mean age 35±12.2, 23 to 47 years) and as no stockings using group, (group 2; 22 women, 8 men, mean age 38±10.8, 27 to 49 years) and. Primary outcomes and secondary outcomes were evaluated. Results: Extremity volumes in Group 1 and Group 2 were reduced from preoperatively 4600±540 ml and 4740 ± 420 ml to postoperatively 4440±430 ml and 4660 ± 400 ml, respectively. There were no differences between two groups by means of time to return to work and complications. Extremity volumes and Visual Analogue Scale pain scores were detected statistically significant reduction at the end of 4 weeks in group 1. Conclusion: Additional use of compression stockings after isolated vena saphena parva stripping can provide significant reduction in extremity edema and visual analog scale pain score. On the other hand, developing complications and time to return to work in both groups seem similar, Amaç: Bu çalışmanın amacı, izole Vena SafenaParva stripingi sonrasında orta basınçlı elastikkompresyon çorabı kullanılmasının etkinliğiniaraştırmaktır.Gereç ve Yöntem: 2011 Ocak ile 2014 Marttarihleri arası izole Vena Safena Parva yetmezliğinedeniyle opere edilen 60 hasta (40 kadın, 20 erkek,yaş ortalaması; 39± 11, 35-58 yaş arası) burandomize kontrollü retrospektif çalışmaya dahiledildi. Ekstremitelere postoperatif 3 gün boyuncaelastik bandaj uygulandı. Hastalar ilaveten 4haftalık kompresyon çorabı giyenler (Grup 1; 18kadın, 12 erkek, yaş ortalaması 35±12,2, 23-47 yaşarası] ve giymeyenler (Grup 2; 22 kadın, 8 erkek,yaş ortalaması 38±10.8, 27-49 yaş arası.) olmaküzere iki gruba ayrıldı. Primer sonlanım vesekonder sonlanım sonuçları değerlendirildi.Bulgular: Çalışma ve kontrol grubunda bacakortalama hacimleri sırasıyla preoperatif 4600±540ve 4740 ± 420 ml iken postoperatif 4. hafta sonunda4440±430 ml ve 4660 ± 400 ml’e geriledi. Dörthaftalık takip döneminde işe dönüş,komplikasyonlar açısından fark gözlenmedi. Bacakhacimleri ve vizuel analog skala ağrı skorlarındagrup 1’de istatistiki olarak anlamlı derecede birazalma saptandı.Sonuç: İzole vena safena parva stripingi sonrasıilave elastik kompresyon çorabı giyilmesiekstremite ödemi ve postoperatif ağrı hissindeanlamlı derecede azalma sağlayabilir. Diğer taraftanvaris çorabı kullananlar ile kullanmayanlarkomplikasyon gelişimi ve işe dönüş zamanıaçısından benzer görünmektedir.Anahtar Kelimeler: Vena safena parva, striping,komplikasyon, skleroterapi

Light-sheet microscopy (LSM), in combination with intrinsically transparent zebrafish larvae, is a method of choice to observe brain function with high frame rates at cellular resolution. Inherently to LSM, however, residual opaque objects cause stripe artifacts, which obscure features of interest and, during functional imaging, modulate fluorescence variations related to neuronal activity. Here, we report how Bessel beams reduce streaking artifacts and produce high-fidelity quantitative data demonstrating a fivefold increase in sensitivity to calcium transients and a 20-fold increase in accuracy in the detection of activity correlations in functional imaging. Furthermore, using principal component analysis, we show that measurements obtained with Bessel beams are clean enough to reveal in one-shot experiments correlations that can not be averaged over trials after stimuli as is the case when studying spontaneous activity. Our results not only demonstrate the contamination of data by systematic and random errors through conventional Gaussian illumination and but,furthermore, quantify the increase in fidelity of such data when using Bessel beams.

The Suomi National Polar-orbiting (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Day-Night Band (DNB) measures visible and near-infrared light extending over seven orders of magnitude of dynamic range. This makes radiometric calibration difficult. We have observed that DNB imagery has striping, banding and other nonuniformities—day or night. We identified the causes as stray light, nonlinearity, detector crosstalk, hysteresis and mirror-side variation. We found that these affect both Earth-view and calibration signals. These present an obstacle to interpretation by users of DNB products. Because of the nonlinearity we chose the histogram matching destriping technique which we found is successful for daytime, twilight and nighttime scenes. Because of the very large dynamic range of the DNB, we needed to add special processes to the histogram matching to destripe all scenes, especially imagery in the twilight regions where scene illumination changes rapidly over short distances. We show that destriping aids image analysts, and makes it possible for advanced automated cloud typing algorithms. Manual or automatic identification of other features, including polar ice and gravity waves in the upper atmosphere are also discussed. In consideration of the large volume of data produced 24 h a day by the VIIRS DNB, we present methods for reducing processing time.

Modern satellite radiometers have many detectors with different relative spectral response (RSR). Effect of RSR differences on striping and the root cause of striping in sensor data record (SDR) radiance and brightness temperature products have not been well studied. A previous study used MODTRAN radiative transfer model (RTM) to analyze striping. In this study, we make efforts to find the possible root causes of striping. Line-by-Line RTM (LBLRTM) is used to evaluate the effect of RSR difference on striping and the atmospheric dependency for VIIRS bands M15 and M16. The results show that previous study using MODTRAN is repeatable: the striping is related to the difference between band-averaged and detector-level RSR, and the BT difference has some atmospheric dependency. We also analyzed VIIRS earth view (EV) data with several striping index methods. Since the EV data is complex, we further analyze the onboard calibration data. Analysis of Variance (ANOVA) test shows that the noise along track direction is the major reason for striping. We also found evidence of correlation between solar diffuser (SD) and blackbody (BB) for detector 1 in M15. Digital Count Restoration (DCR) and detector instability are possibly related to the striping in SD and EV data, but further analysis is needed. These findings can potentially lead to further SDR processing improvements.

Perfect colouring of isonemal fabrics by thin striping of warp and weft with more than two colours is examined. Examples of thin striping in all possible species with no redundancy and with redundant cells arranged as twills are given. Colouring woven flat tori is discussed., Contributions to Discrete Mathematics, Vol 9, No 2 (2014)

At the time this project was launched, INDOT was operating two paint trucks per district (one edge line truck and one center line truck). This project was launched to determine the feasibility of painting all the lane miles in each district with a single paint truck per district. The Greenfield and Crawfordsville districts were chosen to develop and test ideas to enable the transition to painting with just one truck per district. Teams from both districts including paint truck drivers, painters and managers participated in a series of Value Stream Mapping (VSM) sessions facilitated by Purdue Technical Assistance Program (TAP). The Value Stream Maps were then used to identify inefficiencies in the painting operation and opportunities for improvement. These improvement ideas included both process changes and physical alterations to existing paint trucks. An action plan was created for each district to follow to enable them to test the ideas during the 2nd half of the 2013 and first half of the 2014 paint season. The action plans were completed and progress was tracked regarding the performance of the modified trucks and processes. Although the Crawfordsville and Greenfield districts implemented different approaches, both were able to complete painting all of their scheduled lane miles during the season with just 1 truck apiece. The results of this project demonstrated the viability of reducing the statewide fleet of INDOT paint trucks from 12 to 6. At an approximate cost of $400,000 per truck, this translates into an approximate savings of $2,400,000 as the current fleet of 12 aging trucks is replaced with 6 trucks rather than 12. The process changes implemented in this project also demonstrated operational efficiency improvements, which will result in labor savings of approximately 10%.

Perfect colouring of isonemal fabrics by thin and thick striping of warp and weft with more than two colours is introduced. Conditions that prevent perfect colouring by striping are derived, and it is shown that avoiding them is sufficient to allow it. Examples of thick striping in all possible species are given., Contributions to Discrete Mathematics, Vol 8, No 1 (2013)

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2003, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2003, Açık işletmecilikte kaya ve cevher basamaklarında kazı genellikle delme-patlatma yöntemi ile yapılmaktadır. Bu amaçla sırasıyla; delik delme, patlatma, kazı-yükleme ve nakliyat işlemlerinin yapılması gerekir. Uygun olmayan delme-patlatma tasarımı hem kendi maliyetlerini olumsuz etkilemekte hem de daha sonraki izleyen işlemler olan kazı-yükleme ve nakliyat işlerinde sorunların oluşmasına, verim düşüklüğüne ve maliyet artışlarına yol açmaktadır. Bu bakımdan delme-patlatma işleri, kazı-yükleme ve nakliyat işleri ile bir bütün olarak değerlendirilmelidir. Delme-patlatma maliyetlerini düşürmek amacıyla, optimum olmayan bir delme-patlatma tasarımı sonunda oluşacak iri parçalar, kazı-yükleme ve nakliyat maliyetlerini etkileyerek genel maliyetlerde artışa neden olur. Delme-patlatma tasarımını bir çok parametre etkilemektedir. Bu parametrelerin bir kısmı kontrol edilebilir, bir kısmı da kontrol edilemeyen parametrelerdir. Kontrol edilebilen parametreler-delme ve patlama geometrisi; delik çapı, delik yeri, delik eğimi, delik boyu, delik düzeni, dilim kalınlığı, delikler arası mesafe, basamak aynası şekli, basamak yüksekliği, basamak eğimi, sıkılama, delik taban payı, atım grubu boyutları, yemleme, ateşleme ve gecikme süresi gibi parametrelerdir. Kontrol edilemeyen parametreler-kayaç birimlerinin madde ve kütle özellikleri; kayaç dayanımları, kütlesel olarak sağlamlık derecesi, kayaç sertliği, su durumu ve hava şartları gibi parametrelerdir. Delme-patlatma çalışmasında çok sayıda parametrelerin mevcut olması nedeni ile optimum şartların elde edilmesi oldukça zor bir durumdur. Ancak, yapılacak analitik çalışmalar sonucunda, optimuma en yakın değerleri elde etmek çalışma yapılan işletme açısından faydalı sonuçlar üretilmesine katkıda bulunabilir. Yapılan bu çalışmada öncelikli olarak literatürde yer alan delik delme ve patlatma sistemleri incelenmiş ve Bölüm 2’de sunulmuştur. Bölüm 3’de delme-patlatma tasarım parametrelerinin analizi yapılarak performans değerlendirilmesinde kullanılan yöntemler sunulmuştur. Bölüm 4’de Garp Linyitleri İşletmesi’nde (G.L.İ.) delme-patlatma işlerinin optimizasyonu için saha çalışmaları ve analitik çalışmalar sunulmaktadır. Öncelikli olarak G.L.İ.’de mevcut işletme sistemi etüdü yapılmıştır. Daha sonra, çalışma yapılan bölgeye ait formasyonların jeomekanik özellikleri tespit edilerek hali hazırda yürütülen delme ve patlatma işlerinin yerinde ayrıntılı etüdü gerçekleştirilmiştir. Mevcut delme-patlatma tasarım parametrelerinin literatürde önerilen formüllerden yararlanılarak elde edilen sonuçlarla uygunluğunu araştırmak için analitik çalışmalar yapılmıştır. Gerek yerinde yapılan gözlemlerde ve gerekse analitik çalışmalar sonucunda, işletmede delme-patlatma işlerinin iyileştirilmesi amacıyla sistematik denemeler gerçekleştirilmiştir. Literatürde bulunan delme-patlatma optimizasyonu için önerilen formüllerden yararlanılarak 7 adet ön tasarım modeli belirlenmiş olup, bu doğrultuda denemeler gerçekleştirilmiştir. Sonuçların irdelenmesi için önerilen performans analiz yöntemleri (patar sayım yöntemi, ikincil atımlarda patlayıcı tüketimi, ekskavatör yükleme performans analizi ve boyut dağılım analizleri) kullanılarak değerlendirmeler yapılmıştır. Bu denemelerde ekskavatör yükleme performans analizi ve boyut dağılım analizlerinin bir paralellik gösterdiği tespit edilmiştir. İşletmedeki mevcut delme-patlatma tasarımı ve deneme yapılan 7 durum için de ayrıntılı delme-patlatma maliyet analizleri yapılarak sonuçlar sunulmuştur. Delme-patlatma maliyetleri yanında kazı-yükleme ve nakliyat maliyetlerinin de analizi yapılarak çalışma yapılan işletme için optimum durum tespit edilebilir. Şüphesiz; çok parametreli ve kompleks bir proses olan delme-patlatma tasarımı ve optimizasyonunda daha kapsamlı çalışmalar yapılarak elde edilen sonuçların desteklenmesi gerekir., Generally the excavation in rock and ore benches are carried out by drilling-blasting method for open pit mining. For such purpose, drilling-blasting, excavation-loading and transportation works are needed to be carried out in respective order. Improper drilling-blasting designs not only affect their own costs negatively but also cause troubles in the following excavation-loading and transportation works, leading to decreased productivity and increased costs. Hence, drilling and blasting works need to be assessed together with excavation, loading and transportation works as a whole. In order to reduce costs of drilling-blasting activities, large pieces of debris created due to a random drilling-blasting design will affect excavation, loading and transportation costs and thus shall cause an increase in overall costs. Various parameters affect the design of drilling-blasting. Whilst some of these parameters can be controlled the others cannot be. Parameters that can be controlled are the drilling and blasting design parameters ( hole diameter, hole location, hole inclination, hole length, burden, drilled spacing, shape of bench wall, bench height, bench inclination, stemming, subdrilling, dimensions of blasting group, primer blasting elements, ignition and delay time). Parameters that can not be controlled are rocks features and mass characteristics ( rock strength, mass characteristics, rock hardness, water condition and atmospheric conditions). Due to the number of parameters involved in drilling-blasting task, it is extremely difficult to obtain optimum conditions. However, following analytical studies performed, obtaining values at the closest proximity to optimum may contribute to production of results that are beneficial on enterprise’s account. Firstly in this study, drilling and blasting systems existing in literature have been sought, and the conclusions were presented in Section II. In Section III, design parameters of drilling-blasting have been analyzed and methods that are used to determine these parameters were presented. In Section IV, the field studies and analytic studies for optimizing drilling-blasting tasks in Garp Lignite Enterprise (G.L.İ.), these studies were presented. First of all a research was carried out regarding existing operating system in G.L.İ. Afterwards, geo-mechanical features of formations of the study area had been determined and on-site experiments of drilling-blasting parameters have been performed. Analytical studies regarding the compliance of existing drilling-blasting design parameters to those given in literature has been carried out using data of G.L.İ. As a result of on-site observations as well as analytical studies, systematic experiments had been performed in order to improve drilling-blasting works in G.L.İ. Making use of formulas regarding drilling-blasting optimizations readily proposed in literature, 7 different preliminary design models have been determined and the experiments are carried out to that direction. Assessments are carried out by using proposed performance analysis methods (boulder count methods, explosive consumption in secondary blasting, excavator loading performance analysis, size distribution analysis) in order to study the results thoroughly. In these experiments it is determined that the excavator loading performance analysis and size distribution analysis denote a great parallelism. There are also drilling-blasting cost analysis and their results for current drilling-blasting design and 7 other cases examined. As well as the analysis for drilling-blasting costs, those for excavation loading and transportation costs are needed to be carried out and then the optimum state for the operations can be determined. With no doubts, more detailed and complex studies must be performed in order to support the results of this study regarding drilling-blasting design that is a multi-parametered and a rather complex process., Yüksek Lisans, M.Sc.

This article studies the design and the performance of a fault-tolerant distributed storage system dedicated to video. We use a completely distributed approach that permit to reduce the memory cost of the reliability scheme. We experimentally point out the scalability properties of this system.; Cet article étudie la conception et les performances d'un système fiable de stockage distribué dédiée à la vidéo. On utilise une approche complètement distribuée qui permet de réduire le coût mémoire de la stratégie de tolérance aux apnées. Nous évaluons expérimentalement les propriétés d’extensibilité&é de ce système.