Authors: Precious Joseph Ekpo , Uche Osokogwu , Solomon Williams

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Oil and gas companies across the world have expanded their operations to cold environments like the Offshore Deep-water for more conventional and economical reservoirs as a result of global demand for energy. As Hydrocarbon production continues to increase from both conventional and unconventional reservoirs in harsh environments, Hydrates presents a huge problem in the oil and gas industry because it leads to production losses, and is very expensive in trying to prevent its formation or removal. The hydrate blockage during Deepwater oil and gas exploration will also damage the equipment and threaten personal safety. It also leads to flow interruptions, environmental and safety problems, the interruptions leads to plugging of the flowline, Hydrates still cost the oil and gas industries millions of dollars annually. This paper discusses the existing chemical inhibitors used to mitigate hydrates as well as evaluating economically the cost implication for twelve years in Niger-Delta. In this study, three different types of chemical inhibitors (i.e. Methanol, Mono-ethylene glycol and KHI) were economically evaluated through a cash flow model and eventually the Net Present Value, Internal Rate of Return, Profitability Index, Present Value Ratio and Payback Period were determined and Monte Carlo Simulation was also used to get NPV, IRR and their uncertainties. Their charts show that KHI will generate an NPV of $20.34MM if invested in at Return of Investment of 28% and will also take a period of 3.76 years to recover the investment made into the project. From the analysis, KHI is a better project to invest in because it generates more profit and has a lesser risk than Methanol and Mono-ethylene glycol.

Authors: Marsimoyi Terefe Bango

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This paper presents a numerical analysis of different sections of circular, square, and rectangular composite columns subjected to axial and torsional loads to characterize the composite columns section performance for different purposes of construction. To accomplish the objective of this study, a parametric examination was conducted. Nine different types of composite columns were investigated. A [circular, square, rectangular] composite column with concrete-filled, with reinforcement bars, and with embedded steel profile were investigated in detail under axial load only and combined effect of axial and torsional loads separately. The strength of composite column materials considered uniformly for concrete, Steel profile, Reinforcement bars in quality, and utilized to determine their impacts under ultimate axial load capacity was examined. The composite columns under load impacts of various percentage 40%, 50% and 60% of its ultimate axial load capacity (P) with a constant magnitude were numerically analyzed. In this paper, different types of composite columns are taken for analysis by making bottom end fully fixed and another top end as pinned support, while the concentrated load and torsion are applied at this point for loading analysis. The FEM software called Abaqus was used for modeling and analysis of composite column by method of finite element considering three-dimensional models for all composite columns’ materials. Concentrated load and Torsion will be applied on the top end of the composite column at the reference point constraint at top-end by coupling. The result analysis is demonstrated to determine the impacts of various levels of axial loads on the behaviour of columns subjected to axial and torsional loading on different composite material, and assessing high and low stress and strain zones, loading compression, rotation and twisting structural properties was investigated.

Authors: Kamal Abdellatif Sami , Ammar Mohammed Maryod Aborida

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This study was carried out to establish and evaluate an Artificial Neural Networks (ANN) geoid model for the Khartoum State. In the first stage the geometrical geoid heights were obtained from the differences between observed ellipsoidal heights and known orthometric heights of 48 geodetic Ground Control Points (GCP) in the study area. This followed by generating an ANN geoid model to extract the geoid heights from 42 ground control stations in the same study area in the Khartoum State. The main objective of this research study is to apply an ANN to model the Geoid surface using the back propagation algorithm in Khartoum state, through supervised training by geoidal undulations values. The WGS84 GPS/levelling geoid is computed then their results were used for comparison and evaluation of the determined ANN Geoid surface. In this study the geometrical geoid model was determined using the well-known geometrical geoid determination approach taking consideration of the distribution of the existing vertical control points in Khartoum area, with an intention of determining the orthometric heights of any point of unknown heights with uncertainties of less than 5cm. The ANN geoid uncertainties were evaluated and tested at 6 geodetic ground control points. The average difference between the derived geoid heights obtained from the geometrical geoid model, and their corresponding ANN geoid heights was found to be in the range of ±3 cm. Based on the test results of the statistical analysis and the study of a trained artificial neural networks model, the authors were able to estimate the geoid model with acceptable accuracy and can interactively be available for end users. This study showed that, the geoid heights in Khartoum State can be determined with the ANN method with typical accuracy of better than 5cm.

Authors: Ekwuribe James Michael , Okoro Christopher Kalu

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Attempt has been made in previous works to improve the steady state and dynamic performances of the vector controlled induction motor drives. The Input-output (I/O) linearization and decoupling technique which are based on the concepts of differential geometry and vector control has been used in the decoupling of speed or torque from the flux of induction motor drives. This paper investigates the effects of non-linearity on the performance of field oriented control of induction motor drive at intermittent loading, Nonlinear control are better seen implemented in large dynamic systems invoking non linearity. the effects of intermittent loading at no load, full, 10%, 20%, 50% and 80% loading where checked on the speed and electromagnetic torque of the induction motor being controlled, stator current and rotor current were also important parameters affected by non-linearity in control under intermittent loading. The results obtained gave a detailed comparison of the distortions present in motor control when not properly controlled. A comparative study of the system under loading conditions were checked under control for linear and non-linearity. Matlab/Simulink was used to model the induction motor drive and also simulate the dynamic performance of the system as load is being varied. The robustness of Matlab/Simulink was used to enable efficient intermittent loading at various points of the simulation, the data logout tool of Matlab/Simulink were also used for data collection analysis and comparison.

Authors: Fan Chao , Liu Yuan

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Article 13 of Legislation Law establishes the experimental legislation system of our country. In order to better understand and supervise the pilot experiment, the NPC and its Standing Committee usually require the authorized subjects to make work reports on the pilot experiment in the authorization decision. Different from the "central government to the local government" authorization, the pilot situation reporting system is an important institutional guarantee for the "local government to the central government" to enable the authorization subject to obtain and understand the specific practice and experience of the reform pilot system. At the same time, the pilot situation report system is also the supervision system of the higher subject to the lower subject in each practice link. In the practice of Article 13 of the Legislation Law, the pilot report system does not only include the pilot report system stipulated in the authorization decision, but also include the pilot report system stipulated in the pilot rules and the statutory pilot report system. These three pilot reporting systems together constitute a systematic pilot reporting system from "local to central". However, the three pilot reporting systems are not perfect in practice. There are still problems such as the inconsistent authorization decisions on the obligation of pilot reporting, the incomplete role of statutory pilot reporting, the inconsistent content of the pilot report, and the lack of third-party evaluation.

Authors: Abdul Rofik , Rudy Handoko , Rachmawati Novaria

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This study departs from the problem of implementing the policies of the East Kalimantan Provincial Government regarding the protection of sustainable agricultural land in Samarinda City, the factors that hinder the implementation of the East Kalimantan Provincial Regulation on the protection of sustainable agricultural land in the Samarinda City, and the implementation model of the East Kalimantan Provincial Regulation on land protection. Suitable sustainable agriculture in Samarinda City. The research approach method used in this research is phenomenology, involving informants from public officials, government bureaucrats, regional implementing organizations, and the Head of the Mainstay Farmers and Fishermen Contact Group of Samarinda City. Data was collected by means of in-dept interview, Documentation, and Observation categories. The findings of the study are that topography, land use change, economic and social factors in the city of Samarinda are the causes of delays in policy implementation. The logical consequence is the implementation model of the Regional Regulation of the Province of East Kalimantan on Sustainable Food Agricultural Land in the City of Samarinda, the main thing is the preparation of the Regional Regulation of the City of Samarinda on the protection of sustainable agricultural land. guidance to Farmers in Samarinda City and detention of Rice Field Land Certificates not to be converted to other land, and if it is urgent to be converted, it is necessary to have regulations governing the exchange of land with the same area and function as the converted land.

Authors: Shavkat Miralimov

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The article talks about the life and multifaceted activities of Mahmudkhodja Behbudiy, a faithful son of the Uzbek people, the father of the Turkestan Jadid movement, a legal scholar, a great enlightener and intellectual, who sacrificed his life in the struggle for independence of the nation. The life of the great reformer Mahmudkhodja Behbudiy, the genius of human intellect, was extremely difficult and full of contradictions like the turbulent period of late 19th and early 20th century. Hundred years after Behbudiy’s tragic death, his life serves as an exemplary lesson for the young people of present days. The social life of Turkestan in the end of the 19th century is highlighted with the rise of new movement that was destined to play an important role in the region’s political processes. The movement called “Jadidism” (from the Arabic word “Jadid” for ‘new”), united the most progressive thinking intellectuals of the region. Jadidism, having originated as a movement of social thought and initially limited by the framework of ideas aimed at reforming school education, went through a difficult path of development, reaching the point of turning into a powerful political movement with definite political requirements of the national-state self-government of Turkestan. This evolution of the Jadidism movement in Turkestan had become possible due the great contribution of Mahmudkhodja Behbudiy and his multi-faceted work. On the onset of the 20th century, in the pursuit for the national development, enlightenment and education, the Turkestani Jadidists – Mahmudkhodja Behbudiy, Abdulla Avloniy, Munawwar Qori, Abdullah Qodiriy, and many others – realized that in the existing state of colonial exclusion, separated and dispersed rebellions, prevalent ignorance and intolerance, the society’s advancement would not be possible to achieve nor there would be a hope for the spiritual and national liberation. It is hard to fully appreciate the merits of Mahmudkhodja Behbudiy in the creation of new-method Jadid schools, in the formation and development of the national press, publishing, librarianship, dramaturgy and theatrical art. The name of Mahmudkhodja Behbudiy, who spared his life in the struggle for the independence and freedom of the nation, was unjustly forgotten and blown away by the social and political storms of the 20th century. In the modern age of independence, the Republic of Uzbekistan puts emphasis and efforts on restoration of the good name of the great son of the Uzbek people.

Authors: Harjeet Singh , Harmanpreet Singh , Sunil Sharma , Harmanpreet Kaur , Arvinder Kaur , Satwinderjeet Kaur , Nikhil Shri Sahajpal , Alka Chaubey , Navid Reza Shahtaghi , Inderjeet Kaur , Subheet Kumar Jain

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7-Methylxanthine (7-MX, CAS No. 552-62-5, purity 99.46%) is the first orally administered drug candidate, which showed anti-myopic activity in different pre-clinical studies. In the present study, we investigated the in-vivo genotoxic and mutagenic toxicity of 7-MX in Wistar rats using comet/single-cell gel electrophoresis, chromosomal aberration and micronucleus assays after oral administration. For the single-dose study (72 h), two doses of 7-MX 300 and 2000 mg/kg body weight were selected. For a repeated dose 28 d study, three doses (250, 500, and 1000 mg/kg) of 7-MX were selected. The doses were administered via oral gavage in the suspension form. Blood and major vital organs such as bone marrow, lung and liver were used to perform comet/single cell gel electrophoresis, chromosomal aberration, and micronucleus assays. The in-vitro Ames test was performed on TA98 and TA100 strains. In the chromosomal aberration study, a non-significant increase in deformities such as stickiness, ring chromosome, and endoreduplication was observed in bone marrow cells of 7-MX treated groups. These chromosomal alterations were observed upon treatment with doses of 2000 mg/kg single dose for 72 h and 1000 mg/kg repeated dose for 28 d. At a dose of 500 mg/kg, DNA damage in terms of tail length, tail moment, % tail DNA and the olive tail moment was also found to be non-significant in 7-MX treated groups. The Ames test showed the non-mutagenic nature of 7-MX in both strains of TA98 and TA100 of Salmonella typhimurium with or without metabolic activation. Thus, the present work is interesting in view of the non- genotoxicity and non-mutagenicity of repeated doses of 7-MX.

Authors: Darshna , Rahul Kumar , Pradeep Srivastava , Pranjal Chandra

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Since the last decade, significant developments have been made in the area of bone tissue engineering associated with the emergence of novel biomaterials as well as techniques of scaffold fabrication. Despite all these developments, the translation from research findings to clinical applications is still very limited. Manufacturing the designed tissue constructs in a scalable manner remains the most challenging aspect. This bottleneck could be overcome by using bioreactors for the manufacture of these tissue constructs. In this review, a current scenario of bone injuries/defects and the cause of the translational gap between laboratory research and clinical use has been emphasized. Furthermore, various bioreactors being used in the area of bone tissue regeneration in recent studies have been highlighted along with their advantages and limitations. A vivid literature survey on the ideal attributes of bioreactors has been accounted, viz. dynamic, versatile, automated, reproducible and commercialization aspects. Additionally, the illustration of computational approaches that should be combined with bone tissue engineering experiments using bioreactors to simulate and optimize cellular growth in bone tissue constructs has also been done extensively.