Effect of Drag Reducing Agents (DRA) in Water Injection Well

Applying drag reducing agent (DRA) into water injection system has improved injection capacity of wells by reducing the friction that occurs inside the well tubing. Many studies were conducted to understand the behaviour and optimise the performance of DRA when applied in multiphase flow. However, less study is being done to evaluate the effect of DRA on the formation, especially in the near wellbore zone. It is expected that DRA in injected water will cause permeability reduction, albeit the factor and exact percentage of reduction are subject to the current study. A water injection system using core flood equipment was used in this work. Polyacrylamide (PAM) and polysaccharide (Xanthan Gum) were mechanically degraded under high shear rates before injected into the core to simulate field condition. Injection rates were varied so that the relationship between permeability reduction and the rates could be established. It is found that low injection rate of 1cc/min gives more permeability reduction compared to high injection rates at 5cc/min, while Xanthan gum DRA solution gives more permeability reduction compared to polysaccharide DRA solution. Backflow was performed to restore core permeability, but the permeability restored was less than initial permeability. CT scan was run to study the permeability reduction of the core. However, no significant difference was observed. It is suggested that the injection rates need to be considered when designing the water injection wells with DRA additives

Effect of Drag Reducing Agents (DRA) in Water Injection Well

Applying drag reducing agent (DRA) into water injection system has improved injection capacity of wells by reducing the friction that occurs inside the well tubing. Many studies were conducted to understand the behaviour and optimise the performance of DRA when applied in multiphase flow. However, less study is being done to evaluate the effect of DRA on the formation, especially in the near wellbore zone. It is expected that DRA in injected water will cause permeability reduction, albeit the factor and exact percentage of reduction are subject to the current study. A water injection system using core flood equipment was used in this work. Polyacrylamide (PAM) and polysaccharide (Xanthan Gum) were mechanically degraded under high shear rates before injected into the core to simulate field condition. Injection rates were varied so that the relationship between permeability reduction and the rates could be established. It is found that low injection rate of 1cc/min gives more permeability reduction compared to high injection rates at 5cc/min, while Xanthan gum DRA solution gives more permeability reduction compared to polysaccharide DRA solution. Backflow was performed to restore core permeability, but the permeability restored was less than initial permeability. CT scan was run to study the permeability reduction of the core. However, no significant difference was observed. It is suggested that the injection rates need to be considered when designing the water injection wells with DRA additives

Theory And Design Issues Of Underwater Manipulator.

In this paper we discuss the theory and implementation issue that is faced by underwater manipulators designers

Quality assurance and its impact from higher education institutions’ perspectives

Background of the study: The implementation of quality assurance at Morotai Pacific University does not improve and improve the quality of higher education implementation in the Border Area of Morotai Island Regency. This is evidenced by until now the University of the Pacific Morotai does not have university accreditation. Purpose: This research aims to find objective, accountable evidence in helping universities make improvements in developing quality universities and improve strategies in carrying out quality assurance at the college. Method: This research uses mixed methods with sequential explanatory strategies implemented of alumni at the Morotai Pacific University of North Maluku as the Border Region of the Republic of Indonesia. Findings: The results showed that there are still many graduates of pacific morotai universities who do not have a job, and are looking for work. While the perspective of alumni on ability in the academic field is focused on aspects of graduates who have special competencies, general competence, personality competence, and infrastructure. The addition of teaching staff is also one of the concerns of alumni to meet the ratio of lecturers to students. Conclusion: This article defines the essence of the parameters and dimensions of quality assurance of universities in Indonesia, especially at the Morotai Pacific University in North Maluku through the application of quality assurance models

Fuzzy Logic Approach for Hybrid Position/Force Control On Underwater Manipulator.

A fuzzy logic control method for hybrid position/force control of underwater manipulator is proposed in this paper

Modeling And Control Of 2-DOF Underwater Planar Manipulator.

This paper investigates the performance of the fuzzy model reference adaptive control applied on 2-dof underwater planar manipulator (MIMO system). Takagi-Sugeno fuzzification is chosen for the fuzzy system. Proportional-integral update law is used in the adjustment mechanism to obtain a fast parameters adaption

Keberkesanan kaedah pembelajaran berasaskan masalah dalam meningkatkan kemahiran berfikir aras tinggi dan menyelesaikan masalah dalam kalangan pelajar

Aspirasi negara yang diilhamkan dalam Wawasan 2020 ialah mencapai taraf negara maju. Hal ini telah meletakkan kepentingan yang sangat tinggi terhadap pendidikan sebagai pemacu untuk mencapai matlamat menjadi sebuah negara maju yang mampu mendepani cabaran dan permintaan ekonomi yang dipacu oleh sains dan teknologi, seperti yang telah digariskan dalam Pelan Pembangunan Pendidikan Malaysia. Pembelajaran Berasaskan Masalah (PBM) adalah satu pendekatan pengajaran berasaskan masalah sebenar, yang melibatkan penggunaan pelbagai kemahiran untuk menyelesaikannya. Kajian kuasi-eksperimental ini bertujuan mengkaji keberkesanan kaedah PBM dalam meningkatkan Kemahiran Berfikir Aras Tinggi (KBAT) dan kemahiran menyelesaikan masalah pelajar. Kajian ini mengambil masa selama lapan minggu. Instrumen yang digunakan dalam kajian ini ialah soalan ujian pra-pasca, senarai semak dan soal selidik. Kajian ini melibatkan 71 orang responden dari Sekolah Menengah Kebangsaan Tun Ismail yang terbahagi kepada dua kumpulan, iaitu kumpulan rawatan dan kumpulan kawalan. Kesemua responden ini ialah kumpulan pelajar yang mengambil mata pelajaran sains tingkatan empat. Data yang diperoleh dianalisis secara deskriptif dan inferensi menggunakan perisian Statistical packages for Social Science Version 21.0 (SPSS). Hasil dapatan kajian ini membuktikan kaedah PBM berjaya meningkatkan Kemahiran Berfikir Aras Tinggi (KBAT) dan kemahiran menyelesaikan masalah pelajar. Pelajar juga menunjukkan persepsi positif terhadap kaedah PBM ini. Dapatan kajian ini menggambarkan teknik pengajaran dan pembelajaran yang berbeza, menarik serta berkesan dari kaedah tradisional mampu meningkatkan kemahiran pelajar

Global, regional, and national burden of Alzheimer's disease and other dementias, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016.

BACKGROUND: The number of individuals living with dementia is increasing, negatively affecting families, communities, and health-care systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortality, and overall burden of dementia as captured by the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2016, and highlight the most important messages for clinicians and neurologists. METHODS: GBD 2016 obtained data on dementia from vital registration systems, published scientific literature and surveys, and data from health-service encounters on deaths, excess mortality, prevalence, and incidence from 195 countries and territories from 1990 to 2016, through systematic review and additional data-seeking efforts. To correct for differences in cause of death coding across time and locations, we modelled mortality due to dementia using prevalence data and estimates of excess mortality derived from countries that were most likely to code deaths to dementia relative to prevalence. Data were analysed by standardised methods to estimate deaths, prevalence, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs; computed as the sum of YLLs and YLDs), and the fractions of these metrics that were attributable to four risk factors that met GBD criteria for assessment (high body-mass index [BMI], high fasting plasma glucose, smoking, and a diet high in sugar-sweetened beverages). FINDINGS: In 2016, the global number of individuals who lived with dementia was 43·8 million (95% uncertainty interval [UI] 37·8-51·0), increased from 20.2 million (17·4-23·5) in 1990. This increase of 117% (95% UI 114-121) contrasted with a minor increase in age-standardised prevalence of 1·7% (1·0-2·4), from 701 cases (95% UI 602-815) per 100 000 population in 1990 to 712 cases (614-828) per 100 000 population in 2016. More women than men had dementia in 2016 (27·0 million, 95% UI 23·3-31·4, vs 16.8 million, 14.4-19.6), and dementia was the fifth leading cause of death globally, accounting for 2·4 million (95% UI 2·1-2·8) deaths. Overall, 28·8 million (95% UI 24·5-34·0) DALYs were attributed to dementia; 6·4 million (95% UI 3·4-10·5) of these could be attributed to the modifiable GBD risk factors of high BMI, high fasting plasma glucose, smoking, and a high intake of sugar-sweetened beverages. INTERPRETATION: The global number of people living with dementia more than doubled from 1990 to 2016, mainly due to increases in population ageing and growth. Although differences in coding for causes of death and the heterogeneity in case-ascertainment methods constitute major challenges to the estimation of the burden of dementia, future analyses should improve on the methods for the correction of these biases. Until breakthroughs are made in prevention or curative treatment, dementia will constitute an increasing challenge to health-care systems worldwide

Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations