Efficient Graph based Recommender System with Weighted Averaging of Messages

We showcase a novel solution to a recommendation system problem where we face a perpetual soft item cold start issue. Our system aims to recommend demanded products to prospective sellers for listing in Amazon stores. These products always have only few interactions thereby giving rise to a perpetual soft item cold start situation. Modern collaborative filtering methods solve cold start using content attributes and exploit the existing implicit signals from warm start items. This approach fails in our use-case since our entire item set faces cold start issue always. Our Product Graph has over 500 Million nodes and over 5 Billion edges which makes training and inference using modern graph algorithms very compute intensive. To overcome these challenges we propose a system which reduces the dataset size and employs an improved modelling technique to reduce storage and compute without loss in performance. Particularly, we reduce our graph size using a filtering technique and then exploit this reduced product graph using Weighted Averaging of Messages over Layers (WAML) algorithm. WAML simplifies training on large graphs and improves over previous methods by reducing compute time to 1/7 of LightGCN and 1/26 of Graph Attention Network (GAT) and increasing recall$@100$ by 66% over LightGCN and 2.3x over GAT.Comment: Accepted to The Second International Conference on AI-ML Systems (AIMLSystems, October 12-15, 2022

Estimation of volumetric flow rate through a circular duct: Equal area versus Log-Tchebycheff method.

Proper control of airflow through a duct is critical in HVAC application. At present, the airflow rate is typically estimated by means of Equal Area and Log-Tchebycheff methods. Both methods deduce the flow rate based on velocities measured at discrete locations in a cross section; the difference is associated with the rules that prescribe the specific locations. This research aims at making a step towards resolving the existing debate as to which method is preferable for a given situation. To achieve this, two-dimensional numerical simulations of air at a uniform velocity entering a straight circular duct of 60D length were performed over a range of Re from 200 to 54000. It was revealed that in the absence of imperfections that are encountered in a real environment, the Equal Area method estimates the volumetric flow rate better in the laminar flow regime, whereas the Log-Tchebycheff method provides greater accuracy in the turbulent regime. In addition, experiments were conducted for Re of 24400, 54800 and 99400 in a straight circular duct of 32D (D = 0.266 m) length. (Abstract shortened by UMI.)Dept. of Mechanical, Automotive, and Materials Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .A34. Source: Masters Abstracts International, Volume: 44-03, page: 1482. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005

Detection of Region Duplication in Digital Images:A Digital Forensic Approach

Digital images are easy to manipulate and forge due to availability of powerful image processing and editing software. Region duplication is becoming more and more popular in image manipulation where part of an image is pasted to another location to conceal undesirable objects or sometimes to hide some useful information. This thesis presents a detailed study and evaluation of one specific type of digital image forgery detection, known as the copy-move forgery detection. Over the past decade considerable number of technologies and solutions that have been proposed for detection of copy-move forgeries. We will be looking about different techniques - on the basis of time complexity, false positives and false negatives - for the detection of this type of forgery. Firstly, detecting the forgery using different techniques – Auto-correlation, Exact Block matching and exhaustive search – and then comparing these techniques on the basis of different parameters. Some results are very promising and can contribute to ongoing work in this fiel

Insilico Drug Prediction and Validation of Lead candidates on Plasmodium falciparum Erythrocyte Membrane Protein 1(pfEMP1) against Malaria

Malaria is an infectious disease caused by protozoan of the genus Plasmodium. It is transmitted by bite from infected female Anopheles mosquito. Plasmodium falciparum erythrocyte membrane protein 1 (PfEmp1), an antigen that is responsible for the immune evasion of the protozoan. This protein has adhesive properties that cause the infected erythrocytes to bind to the endothelial lining of the blood vessel, thus preventing the infected cells from getting filtered by the spleen. It is found that there is an interaction between the sulphate ion on the endothelial cells and NH1, NH2 of Arg 1467 (A), NZ of Lys 1324 (A) and two bonds with N of Gly 1329 (A) on the protein. Inhibiting this interaction may prevent the evasive action. A Ligand with SO4 interactive region can be used to achieve this. Computer aided drug designing techniques were used to find a new scaffold to solve the purpose. GROMACS was used to simulate the protein-Ligand interaction. It was observed that ZINC17206599 shows the best interaction and may prove to be a promising candidate drug for Malaria. 

Comparison of tunnel widening between interference screw and suture disc fixation after ACL reconstruction using CT scan

Background: It is important to study the cause of tunnel widening which occurs after anterior cruciate ligament (ACL) reconstruction as it may affect tendon to bone healing. Amount of tunnel enlargement that happens after different fixation methods like interference screw or suture discs needs to be compared.The objective of the study was to test the hypothesis that aperture fixation (interference screw) reduces tunnel enlargement compared to suspensory fixation (suture disc) due to reduced graft tunnel motion.Methods: 24 bone tunnel diameters in 12 patients were evaluated by CT scan postoperatively after ACL reconstruction to measure tunnel widening. Two groups were formed, one consisting of 14 tunnels fixed by interference screws (IFS) and other consisting of 10 tunnels fixed with suture disc (SD). The difference between the two groups was compared by unpaired student’s t test.Results: The mean tunnel widening in IFS group was 0.414mm while that in the SD group was 1.23mm. The difference between the means of the two groups was statistically significant (p<0.001). Conclusions: Tunnel widening phenomenon was significantly less with anatomic IFS fixation as compared to suture disc fixation probably due to reduced motion of graft within the walls of bony tunnel and consequently better graft healing

Evaluation of volar locking plate fixation for management of intra-articular fractures of distal end of radius

Background: With the increase in high velocity trauma, the incidence of intra-articular fractures of distal end of radius, particularly in adults- the working class of society is increasing. Normal functioning of wrist is of paramount importance for all activities of daily living and working. The present study was undertaken to evaluate the results of using volar locking plate for fixation of intra-articular fractures of distal end radius, with emphasis on return to pre-injury employment assessment.Methods: It is a combined prospective and retrospective study from January 2013 to June 2016. Twenty patients of intra-articular fractures of distal end of radius (AO type B2 and B3) were treated with volar locking plate through volar approach. The patients were regularly followed up for one year. The assessment of pain, range of motion, activity and grip strength were scored by Green and O’Brien’s system.Results: According to scoring system of Green and O’Brien the patients were assessed at 1 year follow up. 17 patients (85%) showed excellent results (scores 90-100). 2 patients (10%) showed good result (scores 80-89) while 1 patient (5%) had fair outcome (score 65-79). No patient had poor result (score less than 65). 19 patients (95%) returned to their pre-injury employment at 1 year.Conclusions: Open reduction and internal fixation with volar locking plate is reliable and excellent methods of management of intra-articular fracture of distal end of radius especially shear type of injury (AO type B2 and B3) in adults.

The seaweed industry in Sabah, east Malaysia

Seaweed cultivation was introduced in Sabah since 1978 and has increasingly become an economically important natural resource for Malaysia, particularly for Sabah. It was known to have wide application potentials similar or even better than other commodity such as cocoa and palm oil. Two significant seaweed-based industries had started and are developing at a moderate pace. These are seaweed cultivation or farming and the production of semi refined carragenan from seaweed. Beside the government agencies focusing on socio-economy development for rural peoples, there are private local companies venturing in seaweed processing and cultivation at larger scale in Semporna. Three methods of seaweed cultivation have been widely practiced and established in Sabah namely, raft system (MKII), stake system and long line system. The long line system is being widely practiced with approximately 95% of seaweed farmers employing this method. This was due to the facts that the long line system is more economical and practically easy to handle compared to other system. Kappaphycus alverazii is the most common species and widely farmed in Sabah beside Euchema spinosom in small percentage. Sabah is the sole producer for seaweed in Malaysia. GDP in year 2002 was RM21.16 Billion whereby fisheries sector contributed 3.2% of the total GDP. Total production of dried seaweed in 2002 was 2,562.49 MT with the total wholesale value approximately RM 4.4 million. Total export for dried seaweed from Sabah in 2002 was 1,750 MT by weight and RM14 million by value. Most of dried seaweed production in 2002 exported to the United Kingdom (65.5%), Chile (13.0%), Korea (8.0%), Japan (6.0%) and other countries (7.5%). The main issues and challenges facing the seaweed industry in Sabah in particular and in Malaysia in general will be discussed in this paper. Major programmes are in placed to boost the seaweed production in Sabah, subsequently to meet projected production of seaweed in Malaysia in the year 2010 also will be highlighted

Chronic insertional achilles tendon ruptures treated by suture anchor repair and augmentation with flexor hallucis longus tendon transfer

Background: Different surgical procedures have been used for treatment of chronic ruptures of the Achilles tendon with varying results. This study assesses the functional outcomes and complications of chronic insertional tears of Achilles tendon.Methods: 10 patients with chronic ruptures of the Achilles tendon were followed for a mean period of 10.3 months. Only ruptures at or near (within 1 cm) insertion were included. They were treated by direct repair of tendon to calcaneum by suture anchor. Flexor hallucis longus (FHL) tendon transfer fixed to calcaneal tunnel with an interference screw was used to augment the repair.Results: Outcome was assessed by AOFAS Ankle-Hindfoot (AHS) score. The mean preoperative score of 41.2 improved to 85.4 at final follow-up out of a total 100 points. We achieved excellent results in 80% and good outcome in 20% cases. No re-ruptures were noted. Conclusions: In insertional chronic ruptures of Achilles tendon, FHL transfer to calcaneum with interference screw fixation and repair of Achilles tendon with suture anchor is a reliable technique with good outcome and is recommended