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Discover Food ◽  
2022 ◽  
Vol 2 (1) ◽  
Author(s):  
G. D. T. M. Jayasinghe ◽  
B. K. K. K. Jinadasa ◽  
N. A. G. Sadaruwan

AbstractAlginates are natural polysaccharides that are extracted from brown seaweed varieties and it is widely used for their rheological properties. The main step in the extraction protocol of sodium alginate is alkaline extraction. Sodium alginate was produced by dipping the seaweed in 1% formaldehyde and 2.5% of sodium carbonate solution and properties were studied following the standard methods. The amount of sodium alginate yield was 31.7% in Sargassum wightii. The moisture content and the ash content were recorded at 16.82% and 5.20%, respectively. The viscosity and the gel strength were noted as 40 vcP, 4.54 × 10–2 kN with 0.1 M CaCl2 and 6.86 × 10–2 kN with 0.2 M CaCl2 respectively. This study of the extraction method and its properties reveal that Sargassum wightii brown seaweed species have a high affinity to extract the alginate.


2021 ◽  
Vol 1 (1) ◽  
pp. 134-145
Author(s):  
Hadeel S. Abed ◽  
Hikmat N. Abdullah

Cognitive radio (CR) is a promising technology for solving spectrum sacristy problem. Spectrum sensing  is the main step of CR.  Sensing the wideband spectrum produces more challenges. Compressive sensing (CS) is a technology used as spectrum sening  in CR to solve these challenges. CS consists of three stages: sparse representation, encoding and decoding. In encoding stage sensing matrix are required, and it plays an important role for performance of CS. The design of efficient sensing matrix requires achieving low mutual coherence . In decoding stage the recovery algorithm is applied to reconstruct a sparse signal. İn this paper a new chaotic matrix is proposed based on Chebyshev map and modified gram Schmidt (MGS). The CS based proposed matrix is applied for sensing  real TV signal as a PU. The proposed system is tested under two types of recovery algorithms. The performance of CS based proposed matrix is measured using recovery error (Re), mean square error (MSE), and probability of detection (Pd) and evaluated by comparing it with Gaussian, Bernoulli and chaotic matrix in the literature. The simulation results show that the proposed system has low Re and high Pd under low SNR values and has low MSE with high compression.


2021 ◽  
Author(s):  
Hussien Alzaki ◽  
Nadhir Rahmani ◽  
Matthew Carr

Abstract Long-extended reach drilling (ERD) well has become necessary to reach untapped resources. This paper will describe pre-planning, execution and post results of drilling ERD wells with large bore design of 12¼" as the main step out section and deploying 9⅝" casing on shallow TVD of 4,200’. Progressive increase of the ERD ratio and complexity from one well to the next was planned and executed till we reached the longest well deploying 8 KM of 9⅝" casing with 5.4 ERD ratio at 26,179' TD horizontally all the way. A learning curve was established on drilled wells while progressively increasing reach and complexity. Subject well was the longest of any well planned in the field by far. Success involved implementation of technically modeled engineered solutions and verified during execution. Operational procedures including but not limited to: proper planning and execution of well profile to ensure optimum placement in a specific formation and minimum side forces. Drilling and tripping procedures to ensure the lowest friction factor (FF) and allow drilling to target depth (TD) with optimum rig capability. Engineered solution for casing running technologies, which involved rotation and conventional running and floatation. The longest ERD well was drilled to 26,179' TD with field ROP record in 12¼" hole section, maintaining very good hole quality proved by smooth bit trips out of hole and the final trip at TD on elevators. Hole cleaning and fluids strategy was developed and executed efficiently to measure FFs as low as possible for successful 9⅝" deployment. Engineered solution was proposed for 9⅝" deployment and was successfully trial tested on a shorter well to validate simulations. Casing rotation FFs came close to the modeled FFs. The 9⅝" Casing was deployed to bottom as planned and the cement job was performed successfully. Various records were achieved: the subject well achieved the deepest 9⅝" horizontal casing, the deepest 12¼" horizontal at TVD shallower than 5,000'. The longest 12¼" horizontal open hole at TVD shallower than 5,000' with section footage of 16,164'. The 9⅝" casing was deployed as a long string, eliminating the cost and challenges of a liner hanger and the need for a future tieback and also keeping hole sizes available for main and contingency sections to drill the reservoirs ahead. In addition to existing developed procedures and practices for ERD wells, subject well was dealing with the challenge of drilling a long 12 ¼" hole with a torque limitation of 30K lbsf.ft on TDS, and 4200 psi on surface equipment, and running the longest casing horizontally at such a shallow TVD, which is being done the first time globally. The success proved that challenging ERD wells can be drilled with optimum investments on rig capabilities.


Author(s):  
Suncica Sreckovic ◽  
Dusan Todorovic ◽  
Jasmina Stojanovic

Abstract Diabetes mellitus (DM) represents a systemic disorder which afects different organs. Ocular complications of the DM are the worldwide leading cause of blindness. The most common complications are diabetic retinopathy, diabetic cataract, neovascular glaucoma. Recently many investigations point out that DM can cause comlications at ocular surface as well. Condition such as decreased corneal sensitivity, dry eye or neurotrophic corneal ulceraction are the main clinical manifestations of the diabetic keratopathy (DK). Untreated, these conditions can lead to serious visual acuity decrease. Pathological processes, based on chronic inflammation, due to chronic hyperglycemia, are the main step in the process of DK development. Adequate treatment of the main disease - DM is an imperative in maintaining the healthy cornea without subjective sensations of diabetic patients.


2021 ◽  
Vol 36 (2) ◽  
pp. 157-239
Author(s):  
Philippe Gaucher

This paper proves that the q-model structures of Moore flows and of multipointed d-spaces are Quillen equivalent. The main step is the proof that the counit and unit maps of the Quillen adjunction are isomorphisms on the q-cofibrant objects (all objects are q-fibrant). As an application, we provide a new proof of the fact that the categorization functor from multipointed d-spaces to flows has a total left derived functor which induces a category equivalence between the homotopy categories. The new proof sheds light on the internal structure of the categorization functor which is neither a left adjoint nor a right adjoint. It is even possible to write an inverse up to homotopy of this functor using Moore flows.


2021 ◽  
Vol 939 (1) ◽  
pp. 012026
Author(s):  
Sh Khakimov ◽  
S Rajapova ◽  
F Amirkulov ◽  
E Islomov

Abstract This article demonstrates the changes made in the intersection model using PTV Vissim have an impact on reducing an amount of GHG and fuel consumption. One of the most problematic intersections in Namangan, Uzbekistan, was selected and traffic flow during peak hours was studied in order to prepare the simulation of the intersection. The article offers two types of solution as so to lessen the amount of toxic gases and fuel consumption. In the first solution, the situation was improved by optimizing the phase of the traffic light and by changing the cycle duration. The second solution was to reduce the amount of toxic gases and fuel consumption from vehicles by changing the geometric dimensions of the intersection. After the implementation of both solutions, the current state of LOS was raised from D to A level.


Author(s):  
Enrique Canessa ◽  
Livio Tenze

Abstract—A main step for world’s progress is to keep sharing ever-present Ideals for science and education within today’s Virtual Realities. On-line education is transforming human society to new levels in the way people teach and learn during the ongoing SARS-CoV-2 pandemic. There is an increasing interest in having more and more reliable, fast and simple apps to communicate and also to record, assemble and distribute videos and lectures in the fields of Physics & Maths still using traditional didactic methods. We describe here how to accurately reproduce chalkboard classes for the popular YouTube video platform using OpenEyA-YT. The audience can thus be expanded over continents to help mitigate the effects of physical isolation.


2021 ◽  
Vol 13 (21) ◽  
pp. 12210
Author(s):  
Manel Elmsalmi ◽  
Wafik Hachicha ◽  
Awad M. Aljuaid

The supply chain risk management (SCRM) is very critical to strategically support the firms to continuous success. There are, at least, three basic steps in this SCRM process: risk identification, risk evaluation, and risk mitigation (treatment). Whatever happens, the main step is risk mitigation (RM) and mainly sustainable RM. In fact, every risk must be eliminated or controlled as much as possible. The purpose of this paper is to elaborate and evaluate various RM scenarios from an initial risk identification and prioritization solution. The proposed scenario modeling technique is based on morphological analysis (MA) as an explorative scenario tool for RM. MA is used to develop a framework to proactively assess critical risk variables. Firstly, MA is employed to exhaustively create possible RM scenarios and, secondly, to assess the likelihood of each scenario. The proposed approach addresses the need for a basic rubric to help identify and choose RM approaches. A real case study is provided from the food industry to illustrate the application of the proposed approach. To handle all possible MA strategies, a dedicated MORPHOL software package is used. In addition, RM strategies are selected based on sustainability indicators. The case study results prove that MA has a considerable value for SCRM. It shows that firms can adopt multiple robust strategies in the form of a scenario describing all stages of SCRM in an integrated representation.


2021 ◽  
Vol 2099 (1) ◽  
pp. 012023
Author(s):  
V A Gnezdilova ◽  
Z V Apanovich

Abstract The problem of data fusion from data bases and knowledge graphs in different languages is becoming increasingly important. The main step of such a fusion is the identification of equivalent entities in different knowledge graphs and merging their descriptions. This problem is known as the identity resolution, or entity alignment problem. Recently, a large group of new entity alignment methods has emerged. They look for the so called “embeddings” of entities and establish the equivalence of entities by comparing their embeddings. This paper presents experiments with embedding-based entity alignment algorithms on a Russian-English dataset. The purpose of this work is to identify language-specific features of the entity alignment algorithms. Also, future directions of research are outlined.


Author(s):  
Taghreed S. Hussein ◽  
Mohammed R. Ahamad

Preparation of new S-glycosides including thiouracil derivatives as heterobase. The main step of this work is the formation of thiouracil derivatives [1-3] by the condensation reaction of ethyl cyanoacetate, aromatic aldehydes and thiourea to form target compounds [1-3], after protection of the hydroxyl groups in sugar (D-fructose, L- sorbose, and D-galactose), react with hydrobromic acid 45% in glacial acetic acid give different Bromo sugars [a-c], which coupled with prepares thiouracil derivatives [1-3] and propylthiouracil [4] in the presence of K2CO3 to afford the corresponding product S-glycoside analogs [1-4a, 1-4b, 1-4c]. deprotection of the S-glycoside analogs in acid and base medium, led to the free S-glycoside derivatives [1-4d,1-4e,1-4f]. The obtained compounds were tested for their antibacterial and antifungal actives.


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