Fairness in Multiuser Systems with Polymatroid Capacity Region

For a wide class of multi-user systems, a subset of capacity region which includes the corner points and the sum-capacity facet has a special structure known as polymatroid. Multiaccess channels with fixed input distributions and multiple-antenna broadcast channels are examples of such systems. Any interior point of the sum-capacity facet can be achieved by time-sharing among corner points or by an alternative method known as rate-splitting. The main purpose of this paper is to find a point on the sum-capacity facet which satisfies a notion of fairness among active users. This problem is addressed in two cases: (i) where the complexity of achieving interior points is not feasible, and (ii) where the complexity of achieving interior points is feasible. For the first case, the corner point for which the minimum rate of the active users is maximized (max-min corner point) is desired for signaling. A simple greedy algorithm is introduced to find the optimum max-min corner point. For the second case, the polymatroid properties are exploited to locate a rate-vector on the sum-capacity facet which is optimally fair in the sense that the minimum rate among all users is maximized (max-min rate). In the case that the rate of some users can not increase further (attain the max-min value), the algorithm recursively maximizes the minimum rate among the rest of the users. It is shown that the problems of deriving the time-sharing coefficients or rate-spitting scheme can be solved by decomposing the problem to some lower-dimensional subproblems. In addition, a fast algorithm to compute the time-sharing coefficients to attain a general point on the sum-capacity facet is proposed.Comment: Submitted To IEEE Transactions on Information Theory, June 200

Stimulated quantum phase slips from weak electromagnetic radiations in superconducting nanowires

We study the rate of quantum phase slips in an ultranarrow superconducting nanowire exposed to weak electromagnetic radiations. The superconductor is in the dirty limit close to the superconducting-insulating transition, where fluxoids move in strong dissipation. We use a semiclassical approach and show that external radiation stimulates a significant enhancement in the probability of quantum phase slips. This can help to outline a new type of detector for microwave to submillimetre radiations based on stimulated quantum phase slip phenomenon.Comment: 10 pages, 9 figure

A look into colostomy in pediatric patients presented to Al Ribat University Hospital December 2013-December 2014

Background: Colostomy is a very common procedure in pediatric pts. It has a lot of indications and complications.Objectives: 1) To observe the frequency of indications complications of colostomies between patients done in Al- Ribat university hospital and other patients done in other hospitals who presented there for definitive procedure. 2) To determine the final outcome of colostomy in pediatric patients. Materials and Methods: Observational prospective study, performed in patients presented to Al Ribat university hospital including patients admitted for colostomy or for final treatment in the period between December 2013 and December 2014.The stoma related complications were tested using Chi-square. The level of significance was taken as p<0.05. Results: There were 50 patients with the peak age group of 4 years (range: 10 days to 8 years). The male percentage was 70% and female 30%. The indications of colostomy were HSD 29 (58 %,) anorectal malformations 19 (38%), rectal injury 1 (2%) and anal malignancy 1 (2%).Complications occurred in 24 patients (48%) of the studied sample. The commonest complication was prolapse 7(29, 2%) followed by stenosis 5(20.8%). Complications were higher in patients operated as an elective cases in compare to emergency operations (51.8% vs. 43,5), and patients operated by registrars in comparison to other surgical operating levels, and in transverse colostomy in comparison to sigmoid colostomy(57,1% vs 46,5%), and in loop colostomy in comparison to divided colostomy ( 51,2% vs 33,3%), but all these results were statistically not significant. One mortality case was reported during this study (2%).Conclusion: Colostomy being a common procedure in pediatrics with high rates of serious complications deserves special attention for a better outcome.Key words: colostomy, complications, Hirschsprungs disease, anorectal malformation

A comparison of 2% Lidocaine and Epinephrine with 3% Mepivacaine in inferior alveolar nerve block

The purpose of this study was evaluation of anesthesia success rate of 3% mepivacaine compared with 2% lidocaine 1/80000 epinephrine in inferior alveolar nerve block in thirty voluntary students. All of the subjects were healthy and had not received any medicament. They pariticipated for two appointments and each time randomly received an inferior alveolar nerve injection with one of the anesthetic solutions. Before anesthesia the first molar, second premolar, and canine teeth were tested with electric pulp tester (EPT). After injection, when subjects felt numbness in inferior lip, the time for starting of anesthesia was recorded according to schedule time from 3 to 49 minutes after lip numbness. When teeth had no response to EPT in maximal output, the pupal anesthesia was achieved. The t paired test was used for data analysis. Results showed that although subjects felt numbness in their lips, anesthetic success was defined only 76.6% in molars, 73.3% in premolars, and 66.7% in canine teeth after injection of mepivacaine. Success was defined 66.7% & 76.7% in molars and premolars and 53.3% in canine teeth when 2% lidocaine 1/80000 epinephrine was administered. No statistically significant difference was found in onset, success or failure rate between both anesthetic solutions in lidocaine group, however, premolar and molar teeth showed significant differences with canine teeth. Keywords: Inferior alveolar nerve block, Lidocaine, Mepivacain

Tingkat Pendapatan Pedagang Kaki Lima Untuk Memenuhi Ekonomi Keluarga Di Desa Passo Kecamatan Baguala Kota Ambon

Pedagang kaki lima merupakan salah satu pelaku atau usaha ekonomi kerakyatan yang kini bergerak dalam usaha perdagangan sektor informal yang telah banyak tersentuh oles kebijakan pemerintahan daerah . Tujuan mencari ini yaitu untuk dapat mengertahui pengaruh lama usaha , tingkat pendapatan perhari , serta bagaimana pengaruh waktu berjualan terhadap tingkat pendapatan pedagang kaki lima . Tipe penelitian yang digunakan yaitu deskriptif yang dimana berusaha untuk memutuskan pemecahan masalah yang ada dengan menggunakan metode SWOT guna mengetahui kekuatan ( Kekuatan ), Weakness ( Kelemahan ), Opportunity ( Peluang ) dan Ancaman ( Threat ). Hasil penelitian ini menunjukan bahwa tingkat pendapatan pedagang kaki lima di Desa Passo telah memenuhi kebutuhan ekonomi seperti pendidikan , sandang , papan dan pangan serta kesehatan rata-rata memiliki 100% terpenuh

Chatbot Design Challenges and the Effect on User Behavior

Chatbots are efficient artificial intelligence tools employed frequently across various industries such as healthcare, tourism, entertainment, and education, to assist in performing repetitive activities requiring a conversation, thereby facilitating humans to focus on more innovative tasks. This chapter reviews the design challenges of two types of chatbots classified based on their interaction modes: dyadic chatbots interacting with one individual at a time; and polyadic chatbots interacting with multiple individuals simultaneously. Further, the chapter identified the associated challenges in the chatbots, namely: engagement, trust, and human likeliness based on personality types - at a higher level in the chatbot design, together with the impact of each challenge on the user behavior. The authors review the literature in the relevant areas to pinpoint the research gaps requiring more focus within each area of challenge. The research community can address these identified research areas, which will eventually promote a more efficient human-machine collaboration

Effect of nutrient supplementation on single cell protein production from watermelon and pineapple peels

The fast growing population of the world has led to an increased demand for protein rich food; this exerts great pressure on food and feed industries to produce sufficient quantities of protein to meet the high nutrient requirements of vulnerable populations (children and women). Single cell protein (SCP) has proven to be a sustainable approach since agricultural residues can be used for the production. In the present study, efforts were made to improve the growth support capacity of watermelon and pineapple fruit peels by submerged fermentation using Saccharomyces cerevisiae. Fruit hydrolysate media supplemented with glucose and nitrogen recorded the highest concentrations of total carbohydrate (6.6 g/L) and crude protein (20 g/L) on the 16th day of fermentation, as compared to that of the fruit hydrolysate media without supplementation which produced 3.6 g/L of total carbohydrate and 5.6 g/L of crude protein. Similarly, fruit hydrolysate media supplemented with nitrogen recorded higher content of total carbohydrate (5.4 g/L) and crude protein (20 g/L); while fruit hydrolysate media supplemented with glucose produced 5.1 g/L and 6.0 g/L of total carbohydrate and crude protein, respectively. Thus, S. cerevisiae produces higher amount of Single Cell Protein by submerged fermentation of pineapple peel hydrolysate (9.8%) as compared to watermelon peel hydrolysate (2.42%). It was also observed that, the combination of the two fruit peels produces higher SCP than watermelon but lower than pineapple fruit peels. However, supplementation with nutrients (Glucose and Ammonium sulphate) at 2% (w/v) greatly increased SCP production in all the fruit combinations. This suggest that microbial growth support capacity of fruit peels can best be improved by addition of nutrient supplements rather than combining different fruit peels. The findings in this study indicated that pineapple peels could serve as a good substrate for SCP production which is strongly influenced by glucose and ammonium sulphate supplementations.Keywords: Yeast, Single Cell Protein, Watermelon, Pineapple, Saccharomyces cerevisiae

Enhancement of machinability of Inconel 718 in end milling through online induction heating of workpiece

This paper presents the outcome of a study on heat assisted end milling of Inconel 718 using inducting heating technique conducted to enhance the machinability of the material. The heating temperature maintained below the phase transformation temperature was aimed at softening the top removable material layers. The experimental results of both conventional and heat assisted machining were compared. The machinability of Inconel 718 under these conditions was evaluated in terms of tool life, tool wear morphology and chatter. The advantages of Induction heating is demonstrated by an longer tool life and lower chatter. The study showed that preheated machining facilitates up to 80% increase of tool life over conventional machining conducted using TiAlN coated carbide inserts