827 research outputs found
Optimizing Triangular Parabolic Fuzzy EOQ Model with Shortage Using Nearest Interval Approximation
Many Re-searchers have introduced different topics using fuzzy numbers. Triangular parabolic, Trapezoidal parabolic, Hexagonal and octagonal fuzzy numbers are developed in such a way that their membership function attains the highest value only between an interval. If that fuzzy numbers are parabolic in shape when they attains the highest value at midpoint of an interval and called as Triangular parabolic fuzzy number. This paper deals with developing ?-cut from Triangular parabolic membership function and using Triangle shaped values with an Economic Order Quantity(EOQ)model with shortage,here the setup cost ,holding cost, shortage cost are defined as fuzzy numbers. The purpose of this research is to analyse in which point attains it�s maximum value also using midpoint of an interval. Finally numerical examples along with graphical representation of the results are presented
Bitcoin and the World of Digital Currencies
A peer-to-peer system of blockchain, originally started for a cryptocurrency Bitcoin, has caused major disruptions in the stock market. It has affected many businesses if not all, but its significance in the financial world is magnanimous. Historical data (daily rates) for the past 23 months are analyzed to understand the market size, market capitalization and price volatility for Bitcoin. Time series data and financial model are applied to realize the shocks. Monte Carlo simulation is applied to assess the dynamic structure of Bitcoin. With greater volume and activity, the banks and financial intermediaries may become outdated, and the middleman will have no place. It seems like a distant thought, but the facts are pointing toward its reality
Performance Comparison of Particle Filter in Small Satellite Attitude Estimation
The drive towards miniaturization, coupled with the latest advances in onboard processing, has given rise to small satellite missions’ ability to use more complex attitude estimation algorithms to fit their progressive mission requirements. Earth observation missions typically require higher satellite attitude pointing accuracies to precisely control the satellite orientation. Hence, to provide greater confidence in the attitude estimation accuracies, new advanced algorithms are continuously being developed. Satellite attitude estimation must be performed autonomously in real-time whilst optimizing computational resources such as time and memory. Small satellite missions with higher complexities tend to demand more sophisticated requirements, which push the limits of classical attitude estimation methods. The Particle Filter is an advanced Bayesian estimation technique that has shown significant improvements in satellite attitude estimation. This work describes the Particle Filter and its implementation to the attitude and angular rate estimation for a 3U CubeSat in Low Earth Orbit, whilst comparing attitude estimation performance in two different settings: with three-axis magnetometer measurements; and with combined measurements from a three-axis magnetometer and sun sensors. This work further reports that for attitude determination in small satellites, the Particle Filter is a more accurate attitude estimator than the widely used Extended Kalman Filter. The Particle Filter yields attitude estimation accuracy of ±0.01°, while the Extended Kalman Filter attitude estimation accuracy is ±1°. Moreover, the results indicate that the use of an additional sensor improves the attitude estimation accuracy of the Particle Filter by 17%. It is essential to consider different sensor combinations as it helps select the most suitable sensor suite and attitude estimator for an individual small satellite mission
The Amsterdam Hip Protector Study: Compliance and determinants of compliance
Hip protectors appear to be effective in reducing the incidence of hip fractures. However, compliance is often poor. Therefore, the objective of this study was to examine the compliance and determinants of compliance with external hip protectors. A prospective study was performed in residents from apartment houses for the elderly, homes for the elderly and nursing homes with a high risk for hip fracture (n = 276). The study was performed within the framework of the Amsterdam Hip Protector Study, a randomized controlled trial examining the effect of external hip protectors on the incidence of hip fractures. Compliance was assessed by unannounced visits at 1, 6 and 12 months after inclusion in the study. During the visits, a member of the research team checked whether the participant was wearing the hip protector and, if so, whether it was worn correctly. Furthermore, data on potential determinants of compliance were collected by interviewing the participants or their nurses. Compliance was 60.8% after 1 month (n = 217), 44.7% after 6 months (n = 246), and 37.0% after 12 months (n = 230). Of those wearing the hip protector, 86.7%, 91.7% and 96.5% of the participants were wearing the hip protector correctly after 1, 6 and 12 months respectively; and 14.8%, 16.1% and 8.8% respectively reported wearing the hip protector at night. Compliance after 12 months was predicted by the compliance after 1 month (RR = 2.04; 90% CI: 1.05-3.96). Furthermore, people who experienced one or more falls in the half year before baseline had a lower probability of being compliant at 6 months (RR = 0.72; 90% CI: 0.52-0.99). In conclusion, compliance is a very important issue in hip protector research and implementation. Although, the compliance percentages were moderately high during the unannounced visits in this study, not everyone was wearing the protector correctly and most participants did not wear the hip protector during the night
Effect of production systems on the performance of dairy cows in the Gezira State, Sudan
This study was conducted in the Gezira State, Sudan, with the objectives of investigating and comparing the effect of production systems on age at first calving, calving interval, milk yield, herd structure, mortality and growth rate in traditional animal production and organized dairy farms. Six out of eight localities were included in the study. From each locality, 5 herds, each of traditional animal production and organized dairy farms were selected. This survey was carried out using questionnaire involving 40 farmers (including the surveyed farms) from each locality. Means and standard deviations for each studied parameter were calculated using SPSS. The result revealed greater differences in the studied parameters between the two systems of production. Feed had a great influence on animal performance. It could be recommended that, for improving the traditional farm performance, efforts should be payed to upgrade animal genetics through selection from highly producing local cows and introduction of foreign breeds. Feeding improvement in both terms of quality and quantity is also needed.
اجريت هذه الدراسة بولاية الجزيرة بغرض التعرف ومقارنة أثر نظم الانتاج المختلفة علي العمر عند اول ولادة والفترة بين الولدتين وانتاج اللبن وتركيب القطيع والنفوق ومعدل النمو في كل من قطاع الانتاج الحيواني التقليدي ومزارع الالبان المنتظمة . شملت الدراسة ستة من ثمانية محليات. اختير من كل محلية 5 قطعان من كل من قطاع الانتاج الحيواني التقليدي ومزاع الالبان المنتظمة. دعم المسح باستبيان شمل 40 مزارع من كل محلية. حسبت المتوسطات والانحرافات المعيارية لكل عنصر من عناصر الدراسة وذلك باستخدام نظام الحزم الاحصائية للعلوم الاجتماعية ( (SPSS كشفت الدراسة عن فروقات معنوية بين العناصر المدروسة في كل من النظاميين واكدت ان الغذاء له اثر كبير علي اداء الحيوان وكذلك العناصر الأخرى خاصة الوراثية قد يكون لها اثر علي الاداء. من اجل تحسين مزارع الانتاج الحيواني التقليدي توصي الدراسة تبذل مجهودات لرفع الكفاءة الوراثية للحيوان من خلال الاختيار من الابقار المحلية العالية الانتاج وادخال السلالات الاجنبية . أيضاً يجب رفع مستوي الغذاء من الناحية الكمية والنوعية.
 
Stent frame movement following endovascular aneurysm sealing in the abdominal aorta
Purpose: We investigated the incidence and extent of stent migration after endovascular sealing of
abdominal aortic aneurysms (EVAS), its relationship with adherence to the instructions for use of the
Nellix endograft and its association with aneurysm growth.
Methods: In this retrospective single centre study, the clinical data and follow-up CT images of
patients undergoing infra-renal EVAS with a minimum follow-up of 1 year were reviewed. The first
postoperative CT scan at one month and the subsequent scans were used to measure the distances
between the proximal end of the stent and reference visceral vessels using a previously validated
technique. Device migration was based on the Society of Vascular Surgery definition of >10mm
downward movement of either Nellix stent in the proximal landing zone; furthermore, we defined
proximal displacement a downward movement of ≥4mm. Patients were categorised according to
adherence to the old (2013) or new (2016) Nellix IFU. Aneurysm diameter was measured for each
scan and a change of ≥5mm was deemed indicative of aneurysm growth.
Results: Seventy-five patients were eligible for inclusion in our study. Over a 4-year period, migration
≥4mm occurred in 42 (56%) patients and migration of ≥10mm in 16 (21%), with similar incidence in
right and left stents. Migration ≥4mm was significantly more frequent among patients whose
anatomy did not conform to any IFU (p=0.025). Presence of aneurysm growth ≥5mm was observed
in 14 patients (19%) and was significantly associated with proximal displacement ≥4mm (p=0.03).
Conclusion: Infra-renal EVAS may be complicated by proximal displacement and migration,
particularly when performed outside IFU. The definition of migration used for EVAR is inappropriate
for EVAS; a new consensus on definition and measurement technique is necessary
Myosin II regulates the shape of three-dimensional intestinal epithelial cysts.
The development of luminal organs begins with the formation of spherical cysts composed of a single layer of epithelial cells. Using a model three-dimensional cell culture, this study examines the role of a cytoskeletal motor, myosin II, in cyst formation. Caco-2 and SK-CO15 intestinal epithelial cells were embedded into Matrigel, and myosin II was inhibited by blebbistatin or siRNA-mediated knockdown. Whereas control cells formed spherical cysts with a smooth surface, inhibition of myosin II induced the outgrowth of F-actin-rich surface protrusions. The development of these protrusions was abrogated after inhibition of F-actin polymerization or of phospholipase C (PLC) activity, as well as after overexpression of a dominant-negative ADF/cofilin. Surface protrusions were enriched in microtubules and their formation was prevented by microtubule depolymerization. Myosin II inhibition caused a loss of peripheral F-actin bundles and a submembranous extension of cortical microtubules. Our findings suggest that inhibition of myosin II eliminates the cortical F-actin barrier, allowing microtubules to reach and activate PLC at the plasma membrane. PLC-dependent stimulation of ADF/cofilin creates actin-filament barbed ends and promotes the outgrowth of F-actin-rich protrusions. We conclude that myosin II regulates the spherical shape of epithelial cysts by controlling actin polymerization at the cyst surface
Present status of some virus diseases affecting legume crops in Tunisia, and partial characterization of Chickpea chlorotic stunt virus
Field surveys were conducted in Tunisia during the 2005‒2006, 2006‒2007 and 2009‒2010 growing seasons to identify viruses which produce yellowing, reddening and/or stunting symptoms of chickpea, faba bean and pea crops. Tissue blot immunoassay (TBIA) results showed that Chickpea chlorotic stunt virus (CpCSV) was the most common virus, followed by Faba bean necrotic yellows virus, Bean leafroll virus and Beet western yellows virus. The coat protein (CP) gene nucleotide sequence of seven CpCSV isolates collected from different regions of Tunisia was compared with sequences of five other isolates in the NCBI database. A homology tree of the CP nucleotide sequences was prepared and CpCSV isolates were grouped into two clusters. The first group contained two Tunisian CpCSV chickpea isolates collected from Bizerte and Kef; sequenced regions showed a high nucleotiode homology (95%) to that of the Ethiopian and Sudanese CpCSV isolates. The second group included five Tunisian isolates: two from chickpea, two from pea and one from faba bean, which showed a high homology (96%) when compared with the Moroccan, Egyptian and Syrian CpCSV isolates
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