bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of ESBL Production & Antibiotic Resistance Profile of Escherichia Coli Isolated from Patients with Urinary Tract Infections: A Study from Tertiary Care Hospital
Authors: Gunjal P. N.  , Gunjal S. P.
Published: August 2020

Urinary tract infection (UTI), is defined as a disease caused by invasion of urinary tract by microorganisms. Majority of UTI cases are due to bacterial infection constitute about 95% of total UTI cases. About 80% of UTI cases are caused by E.coli producing extended spectrum ?-lactamase (ESBL) producing isolates. In recent years limitations in treating infections caused by multidrug resistant organisms has increased. This study aims to determine ESBL production of E. coli cases from a tertiary care hospital. Methodology: A total 358 midstream urine samples were collected by random sampling method during March 2015 to June 2018. Identification, antibiotic sensitivity testing, performed according to standard protocol following Clinical and Laboratory Standard Institute (CLSI) guidelines, 2013. Screening for ESBL producing E.coli isolates performed using ceftazidime further confirmation done by phenotypic disc diffusion test using combined disc method using ceftazidime (30µg) & ceftazidime/ clavulanic acid (30/10 µg) as per CLSI guidelines. Results: Total 358 specimens processed for urine culture. Gram negative bacilli isolated from 123(34.35 %), out of which 68 (55.28%) were E.coli, 19 (15.44%) K. pneumoniae, 15 (12.19%), Pseudomonas spp. 08 (6.50%), Citrobacter spp and Acinetobacter spp, 03 (2.43%), Proteus mirabilis, 01 (0.81%) Proteus vulgaris and Enterobacter respectively. Out of 68 isolates of E.coli, 65 (95.58%) were MDR, ESBL was detected in 31 (47.69%) out of these 65 isolates. Out of these 31 cases 19 (61.29%) were female and 12 (38.70%) were male cases. Conclusion: This study concludes 47.69% ESBL producing MDR E. coli were isolated from UTI cases with female predominance.
Euglycemic Diabetic Ketoacidosis A Dreaded Complication in Post-Operative Patients In ICU
Authors: Dr. Wasim Feroz  , Dr. Sandeep Nale  , Dr. H S Rawat
Published: August 2020

Diabetic ketoacidosis (DKA) is a life threatening metabolic disorder and a known complication of Diabetes mellitus, caused by insulin deficiency or insulin resistance, which allows the catabolism of free fatty acids into ketone bodies, with high blood sugar levels. A rare variant of it is, euglycemic diabetic ketoacidosis (EKDA). We report a case of 60 year old female who was posted for Posterior lumbar interbody fusion (PLIF) and had this complication postoperatively. We believe that this case would serve as a reminder to all practitioners and intensivist to consider ketosis in a diabetic patient despite their serum glucose levels being within the normal range and all anaesthetist to consider the use of insulin during the intra op period even the blood sugar level is normal in peri operative period. This case report summarizes, in brief, the etiology, pathophysiology and treatment of EDKA.
PENERAPAN FORUM ONLINE BULLETIN BOARD PADA SMARTPHONE ANDROID
Authors: Riki Riki
Published: August 2020

Penerapan forum kedalam dunia internet dapat di implementasikan menggunakan myBB, kemudahan dari fitur myBB dapat membetuk forum dan mengatur forum sesuai kategori yang dibutuhkan. Fitur-fitur yang ada di myBB juga dapat membentuk bulletin board berupa pengumuman . Dengan berkembangpesatnya teknologi informasi sekarang ini, forum tidak hanya di akses sebatas dari komputer pribadi, namun juga telah berhasil diterapkan di smartphone. Android adalah merupakan salah satu sistem operasi smartphone yang bersifat opensource dan mudah dikembangkan untuk membangun aplikasi forum Fakultas Teknik Universitas Maritim Raja Ali Haji. Dan dibangun aplikasi untuk mengakses forum dengan platform android, pembangunan aplikasi android diperuntukan sebagai sisi client dan myBB ditujukan untuk web server. Dengan skema rancangan dua rancangan pembuatan aplikasi tersebut, adapun teknik pembuatan aplikasi tersebut dengan myBB, layanan buzztouch serta eclipse yang telah didukung dengan  ADT (Android Development Tools), maka dilakukan pengembangan sistem menggunakan metode waterfall sebagai tahapan pembangun aplikasi client server untuk  dapat melakukan akses ke forum dan telah dapat diterapkan di Forum Fakultas Teknik Universitas Maritim Raja Ali Haji.
SISTEM INFORMASI PEMASARAN PERUMAHAN TAMAN KURNIA DJAJA BERBASIS WEB MENGGUNAKAN PHP DAN MYSQL
Authors: Munir Zainul Munir
Published: August 2020

Sistem pemasaran rumah yang sedang berjalan pada PT. Kurnia Djaja Makmur Abadi tersebut masih dilakukan secara konvensional, sehingga kurang efisien dalam melakukan promosi rumah karena sedikitnya informasi tentang perumahan yang di jual tersebut. Dalam menganalisis dan merancang program aplikasi yang akan digunakan, penulis menggunakan metode pendekatan dan pengembangan sistem seperti desain implementasi, dan pemeliharaan serta menggunakan alat bantu analisis seperti flowmap, diagram konteks, DFD, kamus data, ERD, relasi tabel, dan struktur file. Implementasi perangkat lunak pengembang yang menggunakan PHP dan MySQL untuk melakukan sebuah transaksi antara pelanggan dan bagian pemasaran, dan agar mudah untuk melakukan penginputan data.Hasil dari penelitian tersebut menemukan kelambatan dalam melakukan pemesanan dan kurang keakuratan pada proses pemberian informasi sehingga menimbulkan masalah dengan pelanggan, oleh sebab itu perancang sistem mencoba merancang aplikasi yang lama. Agar dapat melakukan proses transaksi dengan lancar tanpa ada masalah-masalah seperti pelanggan menunggu lama, dan dapat di percaya keakuratannya dan meminimalisasi kesalahan.
ANALISIS NETWORK SECURITY SNORT METODE INTRUSION DETECTION SYSTEM UNTUK OPTIMASI KEAMANAN JARINGAN KOMPUTER
Authors: Panggabean Parningotan
Published: August 2020

Perkembangan teknologi informasi, khususnya jaringan komputer memungkinkan terjadinya pertukaran informasi yang mudah, cepat dan semakin kompleks. Keamanan jaringan komputer harus diperhatikan guna menjaga validitas dan integritas data serta informasi yang berada dalam jaringan tersebut. Masalah yang dihadapi adalah adanya Log Bug yang didapatkan pada komputer server Dinas Lingkungan Hidup Kota Batam yang diindikasikan adanya serangan Denial of Service (DoS) pada komputer tersebut. Berdasarkan masalah diatas maka penulis mencoba membuat sebuah penelitian yang berjudul “Analisis Network Security Snort menggunakan metode  Intrusion Detection System (IDS) untuk Optimasi  Keamanan Jaringan Komputer” dan diharapkan dapat mendeteksi serangan Denial of Service (DoS). Intrusion Detection System (IDS)  adalah sebuah tool, metode, sumber daya yang memberikan bantuan untuk melakukan identifikasi, memberikan laporan terhadap aktivitas jaringan komputer. Aplikasi yang digunakan untuk mendeteksi serangan menggunakan Snort. Snort dapat mendeteksi serangan DoS. Serangan DoS dilakukan dengan menggunakan aplikasi Loic.
PERANCANGAN SISTEM PAKAR MENDIAGNOSA PENYAKIT KULIT PADA ANAK DENGAN MENGGUNAKAN METODE BACKWARD CHAINING
Authors: Maiyendra Nico Alvio
Published: August 2020

Expert systems (expert systems) in general is trying to adopt a system of human knowledge into a computer, so the computer can resolve the problem as was done by the experts. Or in other words, the expert system is a system designed and implemented with the help of a specific programming language to be able to resolve the problem as done by experts.

In this case I tried to implement an expert system to diagnose skin diseases for children from the symptoms and the causes of skin diseases for children. The purpose of this paper is to build a knowledge-based system on brain cancer using backward chaining method that will be displayed in the form of a website using PHP programming and MySQL database.
CORRELATION OF SYSTOLIC TISSUE VELOCITY WITH LEFT VENTRICULAR DYSFUNCTION IN PATIENTS PRESENTING WITH RHEUMATIC SEVERE MITRAL REGURGITATION
Authors: Iqbal Muhammad Khaleel , Maqbool Muhammad Furrakh , Majid Abdul , Tawwab Shahzad , Butt Usman Mahmood , Saleem Imran
Published: August 2020

Objective: To detect correlation between systolic tissue velocity and left ventricular systolic dysfunction in patients presenting with severe rheumatic mitral regurgitation (MR). Methodology: A comparative study was performed at Punjab Institute of Cardiology, Lahore between October 2016 and February 2018. Fifty eight controls and 192 patients with rheumatic severe MR were included. End systolic dimension (LVESD), end diastolic dimension (LVEDD) and ejection fraction (LVEF) of left ventricle (LV) were taken. Group-1 contained healthy controls. Groups II, III and IV contained the patients of severe MR with non-dilated LV (LVESD ≤40mm and LVEF ≥60%), dilated LV (LVESD ≤40mm and LVEF ≥60%) and decreased LVEF (LVEF<60%) respectively. Tissue doppler was used to measure peak systolic tissue velocity at medial annulus (SV-Med), lateral annulus (SV-Lat) and average velocity (SV-Avg) of each subject. Results: A total of 250 study subjects contained 45.2% (n=113) males and 54.8% (n=137) females. Mean age of the study subjects was 30.8± 9.1. Group-I consisted of 58 controls. There were 69, 67 and 56 subjects in groups II, III and IV respectively. Moving from group-I to group-IV, LVEF decreased from 63.9%±2.2 to 46.2±6.5, LVESD increased from 23.2±2.3 to 49.0±2.9 and LVEDD increased from 45.9±3.5 to 64.3±3.6 respectively. Average systolic tissue velocity (SV-Avg) progressively decreased from group-I being 9.64±0.22 to group-IV being 6.32±0.47. There was a significant negative correlation between LV dysfunction and SV-Avg (spearman’s rank coefficient -0.921, p<0.001). A positive correlation was also found between LVEF and SV-Avg in patients with severe MR only (pearson’s coefficient 0.859, p<0.001). Conclusion: A significant negative correlation exists between the peak tissue systolic velocity and left ventricular dysfunction in patients presenting with severe rheumatic mitral regurgitation. Key words: Mitral Regurgitation, Tissue Velocity, Left ventricular dysfunction
PATTERNS OF CARDIOTHORACIC DISEASES AND PROCEDURES IN A TERTIARY CARE HOSPITAL OF PESHAWAR
Authors: Nasim Omer , Hayat Muhammad Khizar , Rustam Zainab
Published: August 2020

Objectives: To determine the common cardiovascular and congenital heart diseases that required admission and surgical intervention in a tertiary care hospital of Peshawar. Methodology: This was a retrospective study at the cardiothoracic surgery ward of Rehman Medical Institute (RMI). All the admissions over the period of 9 years from 2005 to 2014 into the cardiothoracic surgery ward were reviewed. The data acquired was put into Microsoft Excel 2013 and analyzed using pivot tables for frequencies of different procedures and diagnosis. Results: A total of 9343 patients were admitted during the 9-year period. There were 6516 (69.7%) males and 2827 (30.3%) females. The male to female ratio was 2.30:1. The ages ranged from 1 year to 99 years. Mean age was 41.32 ± 20.56 years. The highest proportion of admissions was in the 50-59 years’ age group followed by 60-69 years and 40-49 years. Coronary Artery Bypass Graft (4617) was the most common procedure performed. Triple Vessel Disease (37%) was the most commonly presented disease to the RMI Cardiology Unit. Conclusion: Majority of patients presented with triple vessel disease and male outnumbered female. CABG was the commonest procedure performed at RMI Cardiac Surgery Unit, Peshawar.Keywords: Cardiovascular Diseases, Heart Valves, Coronary Diseases
POST PCI MYOCARDIAL INFARCTION A SILENT KILLER FACT OR FICTION. DOES IT REALLY EXIST? WHERE DO WE STAND?
Authors: Khan Naveed Ullah , Saghir Tahir , Talpur Muhammad Saeed , Farman Muhammad Tariq , Masood Sobia , Rizvi Nadeem Hasan
Published: August 2020

Objective: To determine the frequency of peri-pocedural myocardial infarction in patients with stable coronary artery disease undergoing elective percutaneous coronary angioplasty. Methodology: This was a descriptive study conducted in the cardiac cath lab of the National Institute of Cardiovascular Diseases Karachi, Pakistan. Patients with stable obstructive coronary artery disease undergoing elective coronary angioplasty were included in this study. PMI was defined as a rise in troponin I above five times the upper limit of the normal range (the third universal definition of MI). Collected data were entered and analyzed using SPSS 19. Results: Among the total of 107 patients male predominance, 82.2% (88), was observed and mean ± SD age of the patients was 52.02 ± 9.10 years with a majority, 92(86.0%), of patients between 41 to 80 years of age. Peri-procedural myocardial infarction (PMI) was found in 16(15.0%) of the patients and PMI was observed to be independent of baseline risk profile and angiographic characteristics of the patients. While, based on criteria of troponin I above three times the upper limit of the normal range, PMI was observed in 22(20.6%) of the patients. Conclusion: High incidence of the post-procedural rise of troponin in our study population is alarming. Further studies are required to identify the cause and hence identifying measures to prevent PMI. Universal single definition is required worldwide in order to get uniform results. Keywords: Post PCI Myocardial Infarction, Coronary angioplasty, Third universal definition
RECURRENT COVID-19 INFECTION IN RECOVERED PATIENTS (A CRITICAL REVIEW)
Authors: Muhammad Anees
Published: August 2020

The pandemic of Coronavirus Disease 2019 (COVID-19) is still grooming throughout the world. However, the number of recovered patients with COVID-19 is also increasing day by day. Some discharged patients from hospitals had shown fever and radiological abnormalities again along with positive real-time reverse transcriptase-polymerase chain reaction (RT-PCR). This might be due to relapse of COVID-19 in recovered patients, secondary bacterial infection, the false-positive result after discharging, or a false negative at discharging yet to determine. In this review, a total of seven studies retrieved, in which 1052 COVID-19 infected patients were studied and followed them for one to six weeks. Among 1,052 patients, 12.1% (n=127) patients were found re-infected having positive RT-PCR with different clinical samples including nasopharyngeal swab, an anal swab, throat swab, and sputum samples. All re-infected patients were found with mild to moderate clinical symptoms. These findings suggest that recurrence of COVID-19 is exist. It is important to develop diagnostic tools further to avoid the false negative or positive results. Moreover, followup studies are required to determine the reason behind the recurrence of COVID-19 in recovered. Besides, we suggest because of the current review, further management of discharged patients is crucial especially for immunocompromised patients, old age patients, or patients with comorbidities. The discharge criteria should be ensured for a recovered patient to prevent the relapse of COVID-19. Keywords: COVID-19, Discharge, Recurrence, Recovered Patients, RT-PCR
SUCCESSFUL PERFORMANCE OF CARDIAC ELECTROPHYSIOLOGICAL PROCEDURES VIA A CONGENITAL INFERIOR VENA CAVA ANOMALY- REPORT OF 2 CASES
Authors: Khanzada Muhammad Faisal , Mumtaz Zubair , Mueed Abdul , Shaikh Sajid Ali , Naqvi Syed Haseeb Raza , Qadir Faisal
Published: August 2020

Background: Femoral vein access is the preferred approach for advancing multiple catheters via the inferior vena cava (IVC) to the heart during routine cardiac electrophysiology study and catheter ablation. Compared to acquired venous abnormalities, congenital inferior vena cava anomalies are encountered rather infrequently in adult electrophysiology procedures and their presence may pose technical procedural challenges. Presentation: We describe 2 cases in which we were able to successfully perform cardiac electrophysiological procedures in the presence of a complex congenital venous anomaly, the left sided IVC. First case was 30 year old gentleman presented with history of recurrent episodes of supraventricular tachycardia terminated with AV nodal blocking agents. Second case was 21 year old boy with WPW syndrome and recurrent supra-ventricular tachycardia. Diagnosis and Management: We managed to pass the EP catheters in both cases with a bit difficulty and angulation, while given I/V heparin to reduce the risk of thrombosis and confirmed the position of catheters via subclavian venous placement of a guidewire. In first case, typical AV node reentry tachycardia was induced which was mapped and ablated in the slow pathway region. In second case, right posterior accessory pathway was ablated at 6 0’clock. CT angiography of the abdominal veins was performed which confirmed the finding of left sided IVC. Follow-up and Outcomes: Abnormalities of the IVC are relatively uncommon. But it is an important condition that may be encountered by electrophysiologist. Catheter ablation of the slow AV nodal pathway and right posterior accessory pathway was safely and successfully performed with this unusual venous anomaly. Keywords: SVT, LEFT IVC, RFA
A música de autor e o cinema de Kleber Mendonça Filho
Authors: Alvarenga Breno
Published: August 2020

Partindo do conceito de “música de autor” proposto por Claudia Gorbman, o presente artigo almeja investigar de que maneira o fenômeno pode ser identificado no cinema de Kleber Mendonça Filho. O intuito é perceber se, por meio da trilha sonora musical da obra do diretor, é possível estabelecer marcas autorais e, portanto, traçar pontos de aproximação e diálogo entre seus filmes. Para tanto, propõe-se a análise da trilha musical de seus três longas-metragens (O som ao redor, Aquarius e Bacurau), dando especial atenção ao uso da canção popular nas narrativas.
“Lugar sonoro” como referencial metodológico: uma proposta conceitual para a análise de filmes históricos
Authors: Dória Daniel
Published: August 2020

Assumindo a premissa de que parte significativa da consciência histórica do presente é modelada a partir a experiência cinematográfica, tomamos por base a proposta de William Guynn (2006) de que podemos pensar os filmes sobre recortes históricos enquanto “lugares de memória” e a de Natalie Zemon Davis (1986) de que a identificação do público para com um filme se daria pautada sobre uma impressão de autenticidade em lugar da fidedignidade factual propriamente dita. No entanto, atentando especificamente para a trilha sonora e o design de som desses filmes, propomos a ideia do “lugar sonoro”, historicamente localizável e reconhecido, por vezes não necessariamente correspondente à verdade cientificamente conhecida, mas que corresponde à ideia que se tem socialmente acerca do objeto, enquanto alternativa conceitual para esse tipo de objeto.
Origens do “som de Hollywood”: a formação do gênero sinfônico a partir de Alfred Newman
Authors: Tápia Daniel
Published: August 2020

A partir da observação do período de formação do gênero sinfônico no cinema sonoro norte-americano, este trabalho procura investigar as influências existentes na formação da prática sinfônica da música de cinema como estética específica, tendo como referência central a atuação do compositor Alfred Newman (1901-1970), considerado aqui como um dos principais agentes desse processo por sua atuação na indústria cinematográfica. O gênero – denominado “gênero sinfônico” –, embora bastante reconhecível, carece de um exame mais detalhado de suas origens e influências, a fim de se expor o papel das diferentes matrizes artísticas que o formaram, especificamente sobre as práticas de escrita instrumental. Para tanto, nos propomos a investigar as origens e relações interculturais existentes no período inicial desse processo (1930-1950), fortemente influenciado pela canção popular norte-americana.
Canções desviantes: momento musical e utopia no cinema queer contemporâneo
Authors: Wlian Luiz Fernando
Published: August 2020

Músicas são potências afetivas. Quando inseridas em filmes narrativos, são capazes de mover a narrativa para outra dimensão, bem como promover novas formas de engajamento do espectador. Assim, podemos pensar em músicas como forças disruptivas, que emergem da narrativa e produzem um reino de novas possibilidades. Nesse sentido, como podemos observar essa ruptura como uma possível fonte de potências dissidentes? De que formas esses momentos podem dar vazão a formas de afeto “outras”, ou a formas de afeto queer? Baseado principalmente nos conceitos de “afetivo-performativo” em Elena Del Río (2008), “momento musical” em Amy Herzog (2010), e “utopia” em Richard Dyer (2002) e José Muñoz (2009), debruço-me sobre momentos musicais do cinema queer contemporâneo, observando o modo como este cinema se utiliza da música para construir sua tessitura queer.
Opacidade sonora no Novo Ciclo de Cinema Pernambucano
Authors: Porto Igor Araújo , Rossini Miriam De Souza
Published: August 2020

A partir de três filmes do chamado Novo Ciclo de Cinema Pernambucano, o artigo propõe pensar a presença de um possível regime de opacidade no som de cinema brasileiro contemporâneo. A análise dos filmes, que exploram as possibilidades estéticas das novas tecnologias de captação, edição e exibição de som, é tensionada com a revisão teórica sobre os conceitos chaves dessa discussão. Para isso parte-se da definição dos regimes de opacidade e transparência, segundo Xavier (2012), e de sua relação com o real. Depois, discute-se o impacto das tecnologias do cinema para esta problemática. Conclui-se que as novas tecnologias introduzidas no período possuem um impacto, embora nem sempre o que se espera delas originalmente.
A escuta visual e a produção sonora em tempo real em performances audiovisuais
Authors: Mapurunga Marina
Published: August 2020

Neste texto, abordo o termo escuta visual para refletirmos sobre a produção sonora em tempo real em performances audiovisuais. A escuta visual está relacionada à imagem sonora que é formada em nossa mente ao visualizarmos um objeto, uma pessoa, uma imagem abstrata ou qualquer outra coisa. Discuto aqui a relação entre a escuta visual e a produção sonora aberta (em tempo real) em performances audiovisuais. Abordo conceitos de Schaeffer (1993), Chion (2012), Iazzetta (2016), Caesar (2012), Rice (2015) e Douglas (1999) relacionados a modos, qualidades e tipos de escuta e a ideia de imagem visual e sonora.
Paulo Silva sobre Carlos Gomes: notas sobre o ensino de contraponto nos séculos XIX e XX
Authors: Macedo Roberto
Published: August 2020

Em 1936 era publicada uma edição da Revista Brasileira de Música comemorativa do centenário de nascimento de Antônio Carlos Gomes (1836-1896). Neste volume, um interessante artigo de Paulo Silva tratava dos estudos de contraponto e fuga do autor de Il guarany. Silva, professor de contraponto e fuga do então Instituto Nacional de Música, selecionou exemplos de exercícios de Gomes realizados na Itália sob a orientação de Lauro Rossi, professor e diretor do Conservatório de Milão. Em muitos desses exemplos, são apontados erros ou deslizes que Silva atribui, pelo menos em parte, às deficiências do método de ensino de Rossi. O presente trabalho busca encontrar as motivações, estéticas e ideológicas, subjacentes aos comentários presentes em seu artigo. A figura do partimento e seus desdobramentos na formação contrapontística de Gomes foram o ponto de partida para a discussão sobre o ensino do contraponto na Europa e no Brasil no século XIX e primeira metade do XX. A isso soma-se uma menção ao ambiente musical brasileiro à época em que o artigo de Silva foi publicado.
An Understanding of Socially-Constructed Knowledge in the Context of Traditional Game-Playing as Theorems-in-Action
Authors: Braz Dias Ana Lúcia , Braz Dias Juliana
Published: August 2020

In this article the authors describe data from an ethnographical study about the playing of Uril, a mancala-type game played in the island of São Vicente, Cape Verde.  They interpret observed game strategies as theorems-in-actions, constructed socially and throughout a long period of time, influenced by socially shared norms and beliefs, as well as by knowledge construction at the individual level.  The authors also use knowledge obtained from a computer-generated database to explore a sequence of game moves observed ethnographically, verifying its robustness and the necessary conditions that make it a winning strategy.  The authors use evidence from ethnographical data to argue that those necessary conditions are tacitly assumed by the players observed.
Insight into Rotational Effects on a Horizontal Axis Wind Turbine NREL Phase ii Using CFD simulation and inverse BEM
Authors: Riyadh Belamadi
Published: August 2020

The present work aims to study the aerodynamic characteristics of the NREL phase II rotor (generated only with S809 profile along the span for an untwisted case) that is a horizontal axis downwind wind turbine rotor and which is assumed to stand isolated in the space. The three-dimensional steady-incompressible flow Reynolds Averaged Navier-Stokes equations are solved by using the commercial CFD package ANSYS FLUENT and, the turbulence closure model k-ω with shear stress transport correction was adopted for all computations. The computations were done for wind speed of 7.2, 10.56, 12.85, 16.3, and 9.18 m.s-1. Results of pressure and torque for considered wind turbine rotor have been directly compared to the available experimental data. The comparisons show that CFD results along with the turbulence model can predict the span-wise loading of the wind turbine rotor with reasonable agreement. Secondly, A comparison of lift and drag coefficients was made between the results obtained using the inverse algorithm BEM based on the calculated pressure distributions and the experimental test data. The result show that the general trend is similar for all sections of the scale, however, large deviation exists between the 2-D and   3-D case.
Direct Torque Control of a Doubly Fed Induction Generator
Authors: Ben Amar Asma
Published: August 2020

In this paper a direct torque control system is proposed and is applied to doubly fed induction generator (DFIG) based wind power generation systems. In this control system the rotor flux and the electromagnetic torque are estimated based on the rotor voltage and currents measurements. The validity and effectiveness of this control is demonstrated by some simulation results.
Numerical Study of a Turbulent Burner by Means of RANS and Detailed Chemistry
Authors: Hafid Mohamed
Published: August 2020

The present paper shows a numerical study of the Co-flow turbulent flame configuration using the Reynolds Averaged Navier-Stokes (RANS) modelling with detailed chemistry. The presumed Probability Density Function (PDF) model combined with the k-Ɛ turbulence model is adopted. The GRI Mech-3.0 mechanism that involves 53 species and 325 reactions is used. The effect of the turbulent Schmidt number Sct and the C1ε constant in the turbulent dissipation transport equation is highlighted. Despite the simplicity of RANS approach compared to other complex models such as LES and DNS, the results show that this approach is still able to simulate the turbulent flame.
Optimal Planning of On-Grid Hybrid Microgrid for Remote Island Using HOMER Software, Kish in Iran
Authors: Jahangiri Mehdi
Published: August 2020

HOMER software functions as a tool for modeling and optimization of an energy generation micropower system based on renewable technologies. In this paper for the first time the monthly real load data have been used in HOMER to design a renewable-based microgrid in grid-connected mode for Kish Island, Iran. The calculations were performed in a way that the designed system could supply the load demand of the studied area with the lowest cost, least pollution, and highest reliability. To overcome the intermittency of renewable energy sources such as wind and solar, a combination of these sources in a hybrid system and installation of battery storage systems were considered. The solar radiation and wind speed data required by the software were obtained from the country’s meteorology and NASA website and used in the software. The analysis results of four scenarios, including national grid/diesel generator, national grid/diesel generator/solar cell, national grid/diesel generator/wind turbine, and national grid/diesel generator/solar cell/wind turbine, showed the prices per kWh of $0.483, $0.505, $0.472, $0.537, respectively. In these scenarios, the share of renewable energies was 0%, 8%, 11%, and 26%, respectively. The highest amount of electricity sold to the national grid was 1597095 kWh/y for the fourth scenario which had also the lowest rate of CO2 emissions by 4128650 kg/y.
A Review of Requirement Engineering Process Models, Tools & Methodologies
Authors: Faroom Saeed
Published: August 2020

As we are living in the Era of Computer Science and almost all individuals and the organizations are completely relying on software systems. The requirement engineering is the most vital and important aspect in the success of any software engineering project. Requirement Engineering is a set of different process that works at different levels, which are incorporated at individual and organizational level Projects We need to consult different sources to find requirements. We need to involve personals from the different fields to find a set of quality requirements. The security issues undergoes as soon as early in the 1st phase of requirements. It is shown from the studies that if we consider Quality Process of Requirement Engineering at the phase it results in saving of million dollars. This paper contains the details study and comparison of different RE Process Models and Requirement Elicitation techniques. This paper elaborates the vital aspects of different Requirement Engineering Process models that help in the selection of appropriate model for the Requirement Engineers and practitioners working in the industry. This Paper also Focus on the giving a detailed view of Elicitation techniques and comparative study including the characteristics and their strengths and weakness. Some strengths and weakness found during detailed study are also structured and listed that is also the helpful for the Appropriate selection of RE Process model.
Control of 3x7 matrix converter with PWM three intervals modulation
Authors: Rezaoui Mohamed Mounir, Imad Merzouk , Bessous Noureddine
Published: August 2020

Direct Power conversion from fixed AC voltage into variable AC voltage is gaining a significant attention, especially in case of multi-phases machines/generators; for such reason a new algorithm to control 3x7 matrix converter (MC) is developed in this paper, wherein the main aim is to control multi-phases induction motor/generator connected to the electrical grid with a novel converter (except matrix converter), for that the PWM three intervals modulation strategy is modified from the control of 3x3 MC to 3x7 MC; which is directly connected to the network through a three phase input in order to overcome the supplying problems, on the other side seven phases have been used as an output to benefit the advantages of the multi-phases machines. This paper intends in the first place to explain the 3x3 MC, then to manipulate the control equation for the purpose of making it suitable for controlling the 3x7 MC effectively, thus a good performance can be clearly seen according to the quality of the output voltage/current under typical R-L load, the shift between phases and the THD evaluation. The obtained simulation results which demonstrate the efficiency of the new control algorithm are presented and discussed.
Modeling solar desalination with reverse osmosis (RO) powered by concentrating solar power (CSP) plan
Authors: Remlaoui Ahmed , . Hammou Soumia, Bent Abdelkader Nafissa
Published: August 2020

This article deals with the desalination of seawater and brackish water, which can deal with the problem of water scarcity that threatens certain countries in the world; it is now possible to meet the demand for drinking water.  Currently,  among  the  various  desalination  processes,  the  reverse  osmosis  technique  is  the  most  used. Electrical energy consumption is the most attractive factor in the cost of operating seawater by reverse osmosis in desalination plants.  Desalination  of  water by  solar  energy  can be  considered  as a  very  important  drinking  water alternative.  For  determining  the  electrical  energy  consumption  of  a  single  reverse  osmosis  module,  we  used  the  System  Advisor  Model  (SAM)  to  determine  the  technical  characteristics  and  costs  of  a  parabolic  cylindrical installation and Reverse Osmosis System Analysis (ROSA) to obtain the electrical power of a single reverse osmosis module. The electrical power of a single module is 4101 KW; this is consistent with the manufacturer's data that this power must be between 3900 kW and 4300 KW. Thus, the energy consumption of the system is 4.92 KWh/m3.Thermal power produced by the solar cylindro-parabolic field during the month of May has the maximum that is 208MWth, and the minimum value during the month of April, which equals 6 MWth. Electrical power produced by the plant varied between 47MWe, and 23.8MWe. The maximum energy was generated during the month of July (1900 MWh) with the maximum energy stored (118 MWh).
Voltage sensorless based virtual flux control of three level NPC back-to-back converter dfigunder grid fault
Authors: Bessous Noureddine , . I. Merzouk, MM. Rezaoui, A. Gafazi
Published: August 2020

In this paper, a harmonic elimination of grid and stator currents of doubly fed induction generator (DFIG) in case of grid fault without line voltage sensors is proposed . This can be achieved by compensating power based on virtual flux voltage sensorless technique. Direct power control with space vector modulation (DPC-SVM) is used to control both grid-side (GSC)and rotor-side converters (RSC). To achieve the control objective, compensated active and reactive powers are calculated based on virtual flux technique with balanced and harmonic free current as a control target. A theoretical analysis of active and reactive powers under unbalanced voltage source is clearly demonstrated and the effect of grid fault on the performance of DFIG is profoundly discussed. Simulation results verified the effectiveness of the modified control strategy.
Effect of the fluidic injection on the flow of a converging-diverging conical nozzle
Authors: Benderradji Razik
Published: August 2020

The flow in an Over-Expanded Nozzle is subjected to shock waves leading to the unsteady separation of the boundary layer. Free detachment may be followed by a restricted detachment. During the expansion regime in propellant nozzles, several physical phenomena are encountered: supersonic jet, jet separation, adverse pressure gradient, shock wave, turbulent boundary layer, highly compressible mixture layer, return flow, large scale turbulence. These very complex phenomena can considerably affect the performance of the nozzle.The numerical investigation was performed by the CFD-FASTRAN search code, using the k-w SST model as the turbulence model. The calculation is performed by solving the Navier-Stokes equations of two-dimensional compressible turbulent flow. It is based on the study of the fluidic vectorization phenomenon of the thrust of a double-injection convergent-divergent supersonic conical nozzle. The study is based on the effect of the ratio of NPR pressures with SPR = 1 on the overall structure of shock waves. The calculation is highlighting the behavior of a flow that has not neglected. In particular, the appearance of the separation zone formed by the fluid jet and the deflection of the main jet cause separation shocks.
Numerical study of a new earth-air heat exchanger configuration designed for Sahara climates
Authors: Hadjadj Abdessamia
Published: August 2020

Thermal performance for cooling and heating in the building can be achieved by the novel shape of the earth–air heat exchanger (EAHE). In a heavily populated area such as City, Due to the limited ground space. EAHE systems are rarely used, for most residential andcommercial utilization.This paper presents a numerical investigation of the thermal performance of a spiral-shaped configuration Spiral Earth to Air Heat Exchanger SEAHE intended for the summer cooling inhot and arid regions of Algeria. A parametric analysis of the SEAHE has been performed toinvestigate the effect of diameter, depth, pipe length and of airflow rate on the outlet air in theexchanger. Results show that the specific heat exchange is used to cool in an arid zone (south-east of Algeria). When the ambient temperature varies between 40°C and 45 °C, the coolingtemperature varies between 25°C and 29 °C. Temperature difference inlet and outlet airexchanger 18°C, these values are quite acceptable with for cooling the building.
Chemical composition and source attribution of submicron aerosol particles in the summertime Arctic lower troposphere
Authors: Köllner Franziska , Schneider Johannes , Willis Megan D. , Schulz Hannes , Kunkel Daniel , Bozem Heiko , Hoor Peter , Klimach Thomas , Helleis Frank , Burkart Julia , Leaitch W. Richard , Aliabadi Amir A. , Abbatt Jonathan P. D. , Herber Andreas B. , Borrmann Stephan
Published: August 2020

Abstract. We use airborne measurements of aerosol particle composition to demonstrate the strong contrast between particle sources and composition within and above the summertime Arctic boundary layer. In-situ measurements from two complementary aerosol mass spectrometers, the ALABAMA and the HR-ToF-AMS, with black carbon measurements from an SP2 are presented. Particle composition analysis was complemented by trace gas measurements, satellite data, and air mass history modeling to attribute particle properties to particle origin and air mass source regions. Particle composition above the summertime Arctic boundary layer was dominated by chemically aged particles, containing elemental carbon, nitrate, ammonium, sulfate, and organic matter. From our analysis, we conclude that the presence of these particles was driven by transport of aerosol and precursor gases from mid-latitudes to Arctic regions. Particularly, elevated concentrations of nitrate, ammonium, and organic matter coincided with time spent over vegetation fires in northern Canada. In parallel, those particles were largely present in high CO environments (> 90 ppbv). Additionally, we observed that the organic-to-sulfate ratio was enhanced with increasing influence from these fires. Besides vegetation fires, particle sources in mid-latitudes further include anthropogenic emissions in Europe, North America, and East Asia. The presence of particles in the Arctic lower free troposphere correlated with time spent over populated and industrial areas in these regions. Further, the size distribution of free tropospheric particles containing elemental carbon and nitrate was shifter to larger diameters compared to particles present within the boundary layer. Moreover, our analysis suggests that organic matter when present in the Arctic free troposphere can partly be identified as low-molecular weight dicarboxylic acids (oxalic, malonic, and succinic acid). Particles containing dicarboxylic acids were largely present when the residence time of air masses outside Arctic regions was high. In contrast, particle composition within the marine boundary layer was largely driven by Arctic regional processes. Air mass history modeling demonstrated that alongside primary sea spray particles, marine-biogenic sources contributed to secondary aerosol formation by trimethylamine, methanesulfonic acid, sulfate, and other organic species.
Development of an automatic linear calibration method for high-resolution single-particle mass spectrometry: improved chemical species identification for atmospheric aerosols
Authors: Zhu Shengqiang , Li Lei , Wang Shurong , Li Mei , Liu Yaxi , Lu Xiaohui , Chen Hong , Wang Lin , Chen Jianmin , Zhou Zhen , Yang Xin , Wang Xiaofei
Published: August 2020

Abstract. The mass resolution of laser desorption ionization (LDI) single-particle
aerosol mass spectrometry (SPAMS) is usually low (∼500),
which has been greatly improved by the recent development of the delayed ion
extraction technique. However, due to large fluctuations among LDI processes
during each laser shot, accurate calibration of the mass-to-charge ratio for
high-resolution SPAMS (HR-SPAMS) spectra is challenging. Here we developed an automatic
linear calibration method to improve the accuracy of mass-to-charge (m∕z)
measurement for single atmospheric aerosol particles. Laboratory-generated
sea spray aerosol and atmospheric ambient aerosol were tested. After the
calibration, the fluctuation ranges of the reference ions' (e.g., Pb+ and SO4+) m∕z reaches ±0.018 for sea spray aerosol and ±0.024 for ambient aerosol in average mass spectra. With such m∕z accuracy, the HR-SPAMS spectra of sea spray aerosol can easily identify elemental compositions of organic peaks, such as Cx, CxHy and CxHyOz. While the chemical compositions of ambient aerosols are more complicated, CxHy, CxHyOz and CNO peaks can also be identified based on their accurate mass. With the improved resolution, the time series of peaks with small m∕z differences can be separated and measured. In addition, it is also found that applying high-resolution data with enhanced mass calibration can significantly affect particle classification (identification) using the ART-2a algorithm, which classify particles based on similarities among single-particle mass spectra.
Reviews and syntheses: The biogeochemical cycle of silicon in the modern ocean
Authors: Tréguer Paul J. , Sutton Jill N. , Brzezinski Mark , Charette Matthew A. , Devries Timothy , Dutkiewicz Stephanie , Ehlert Claudia , Hawkings Jon , Leynaert Aude , Liu Su Mei , Llopis Monferrer Natalia , López-Acosta María , Maldonado Manuel , Rahman Shaily , Ran Lihua , Rouxel Olivier
Published: August 2020

Abstract. The element silicon (Si) is required for the growth of silicified organisms in marine environments, such as diatoms, which consume vast amounts of Si together with N, P, and C, connecting the biogeochemical cycles of these elements. Thus, understanding the Si cycle in the ocean is critical for understanding issues such as carbon sequestration by the ocean's biological pump. In this review, we show that recent advances in process studies indicate that total Si inputs and outputs, to and from the world ocean, are 57 % and 18 % higher, respectively, than previous estimates. We also update the total ocean silicic acid inventory value, which is about 24 % higher than previously estimated. These changes are significant, modifying factors such as the geochemical residence time of Si, which is now about 8000 years and two times faster than previously assumed. In addition, we present an updated value of the global annual pelagic biogenic silica production (255 Tmol-Si yr−1) based on new data from 49 field studies and 18 model outputs, and provide a first estimate of the global annual benthic biogenic silica production due to sponges (6 Tmol-Si yr−1). Given these important modifications, we address the steady state hypothesis of the Si cycle for past and modern oceans, and propose a possible steady state scenario for the global ocean (inputs = outputs = 14.8 Tmol-Si yr−1) and boundary exchange zone. Case studies for future programs are highlighted, and potential impacts of global change on the marine Si cycle discussed.
What could we learn about climate sensitivity from variability in the surface temperature record?
Authors: Annan James D. , Hargreaves Julia C. , Mauritsen Thorsten , Stevens Bjorn
Published: August 2020

Abstract. We examine what can be learnt about climate sensitivity from variability in the surface air temperature record over the instrumental period, from around 1880 to the present. While many previous studies have used trends in observational time series to constrain equilibrium climate sensitivity, it has also been argued that temporal variability may also be a powerful constraint. We explore this question in the context of a simple widely used energy balance model of the climate system. We consider two recently proposed summary measures of variability and also show how the full information content can be optimally used in this idealised scenario. We find that the constraint provided by variability is inherently skewed, and its power is inversely related to the sensitivity itself, discriminating most strongly between low sensitivity values and weakening substantially for higher values. It is only when the sensitivity is very low that the variability can provide a tight constraint. Our investigations take the form of “perfect model” experiments, in which we make the optimistic assumption that the model is structurally perfect and all uncertainties (including the true parameter values and nature of internal variability noise) are correctly characterised. Therefore the results might be interpreted as a best-case scenario for what we can learn from variability, rather than a realistic estimate of this. In these experiments, we find that for a moderate sensitivity of 2.5 ∘C, a 150-year time series of pure internal variability will typically support an estimate with a 5 %–95% range of around 5 ∘C (e.g. 1.9–6.8 ∘C). Total variability including that due to the forced response, as inferred from the detrended observational record, can provide a stronger constraint with an equivalent 5 %–95 % posterior range of around 4 ∘C (e.g. 1.8–6.0 ∘C) even when uncertainty in aerosol forcing is considered. Using a statistical summary of variability based on autocorrelation and the magnitude of residuals after detrending proves somewhat less powerful as a constraint than the full time series in both situations. Our results support the analysis of variability as a potentially useful tool in helping to constrain equilibrium climate sensitivity but suggest caution in the interpretation of precise results.
Mathematical foundation of Capon's method for planetary magnetic field analysis
Authors: Toepfer Simon , Narita Yasuhito , Heyner Daniel , Kolhey Patrick , Motschmann Uwe
Published: August 2020

Abstract. Minimum variance distortionless projection, the so-called Capon method, serves as a powerful and robust data analysis tool when working on various kinds of ill-posed inverse problems. The method has not only successfully been applied to multi-point wave and turbulence studies in the context of space plasma physics, but also is currently being considered as a technique to perform the multipole expansion of planetary magnetic fields from a limited data set, such as Mercury's magnetic field analysis. The practical application and limits of the Capon method are discussed in a rigorous fashion by formulating its linear-algebraic derivation in view of planetary magnetic field studies. Furthermore, the optimization of Capon's method by making use of diagonal loading is considered.