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Abstract Increasing carbon dioxide (CO2) emissions from steel plants due to ever-growing steel production make the increased use of scrap-based production routes more attractive. Also, increasing demands for ultrahigh-strength steels (UHSSs) in commercial and military applications have raised interest in finding alternatives to the expensive steels currently used. This thesis studies the possibilities of using low-cost air induction melting followed by refining using electroslag remelting (ESR) for the production of ultrahigh-strength, tough steel. The influence of ESR on the chemical composition, cleanliness, microstructure, and mechanical properties of novel martensitic and martensitic-bainitic UHSSs is examined to provide a good platform for the future production of tough UHSSs using the above-mentioned route. As a starting point for the studies of the steels concerned, the effect of cooling rate from austenite on phase transformation temperatures and final microstructures, as well as the mechanical properties in the as-cooled, untempered condition, are examined. Also, the evolution of precipitation and microstructure during the thermomechanical processing of austenite is described. Furthermore, the influence of double austenitization and quenching followed by tempering at 200 °C is discussed. ESR is shown to lead to a high yield of alloying elements, low levels of impurities and non-metallic inclusions (NMIs) and a refinement of the final microstructures due to slight changes in the chemical composition. The effect of ESR on mechanical properties depends on the steel composition. For the studied steels, the cooling rates leading to the formation of martensite provide a better combination of strength and toughness than a cooling rate that leads to proeutectoid carbides and granular bainite. It is shown that good combinations of strength and toughness can be obtained through the use of the following process route: low-cost air induction melting, ESR, and temperature-controlled forging and cooling followed by reheating, quenching and tempering at 200 °C. Charpy-V impact toughness can be improved by applying double austenitization and quenching prior to tempering. ; Tiivistelmä Kasvihuonepäästöt (CO2) kasvavat jatkuvasti, koska teräksen valmistus ja kulutus lisääntyvät. Tämä lisää kiinnostusta myös romupohjaiseen teräksenvalmistukseen, koska se mahdollistaa päästöjen vähentämisen. Lisäksi nykyisille ultralujille teräksille, joita voidaan käyttää erilaisissa kaupallisissa sovelluksissa, haetaan valmistusteknisesti edullisempia vaihtoehtoja. Opinnäytetyössä selvitettiin mahdollisuutta hyödyntää ultralujien teräksen valmistuksessa teknisesti edullisen induktiosulatuksen ja sähkökuona-uudelleensulatuksen (ESR = electroslag remelting) yhdistelmää. ESR:n vaikutusta selvitettiin uusien martensiittisten ja martensiittis-bainiittisten ultralujien terästen kemialliseen koostumukseen, epäpuhtauksiin, mikrorakenteeseen ja mekaanisiin ominaisuuksiin. Tarkoituksena on mahdollistaa ultralujien terästen tehokas tuotanto tällä valmistusteknologialla. Lähtökohtana on jäähdytysnopeuden vaikutus austeniitti-ferriitti faasinmuutoslämpötiloihin sekä niiden vaikutus mikrorakenteisiin ja mekaanisiin ominaisuuksiin, kun teräksiä ei ole päästökäsitelty. Tähän yhdistettiin kaksinkertainen austenointi-, karkaisu- ja 200 °C päästökäsittely. Lisäksi tutkimuksessa selvitettiin myös erkaumien ja mikrorakenteen muodostuminen termomekaanisessa kuumamuokkauksessa. Tutkimuksessa osoitettiin, että ESR:n tekniikka johtaa erittäin hyvään seosaineiden tuotokseen, niiden pieneen hajontaan, alhaiseen epäpuhtaustasoon ja siten vähäiseen määrään ei-metallisia sulkeumia. Tällöin saadaan lopputuotteen mikrorakenne ja mekaaniset ominaisuuden tarkasti optimoitua ja ominaisuushajonta jää varsin pieneksi. Tutkituille teräksille jäähdytysnopeudet, jotka aikaansaavat martensiitin muodostumisen, antavat paremman lujuus-sitkeys yhdistelmän kuin jäähdytysnopeus, joka johtaa esieutektoidisen karbidin ja granulaarisen bainiittiin muodostumiseen. Tutkimuksessa osoitettiin, että erinomaiset lujuuden ja sitkeyden yhdistelmät voidaan saada aikaan käyttämällä prosessireittiä: induktiosulatus, ESR, lämpötilakontrolloitu taonta ja jäähdytys, jota seuraa uudelleenkuumennus, karkaisu ja päästö 200 °C. Lisäksi kylmänkestävyyttä (Charpy-V testi) voidaan parantaa käyttämällä kaksinkertaista austenitointia, karkaisua ja päästöä.

Medicinal plants are being looked at as potential new sources of medicines that could replace antibiotics in the treatment of antibiotic-resistant bacteria. The aim of this study is to measure the effect of plant extracts on Proteus mirabilis growth to determine the antibacterial activity of them . Methods: Experimental, in vitro, of Al-Mustaqabal University Collage, The effects of four plant extracts on Proteus mirabilis were assessed. At a concentration of 10%, the activity was assessed using the well diffusion method. Result: Four aqueous plant extracts were tested for antibacterial activity (Peganum harmala, Piper nigrum, Syzygium aromaticum and Cinnamomum zeylanicum) has been evaluated against Proteus mirabilis (Isolated from urinary tract infection). The concentration was used for each type of extract 10mg\ml. In this concentration, the aqueous extract was effective against Proteus mirabilis with inhibition zones of 18 mm, 15 mm and 14 mm respectively, and extract of Cinnamomum zeylanicum shown no inhibition zone. Conclusion: The aqueous extract of Peganum harmala against Proteus mirabilis, showed the highest inhibition of 18mm with the concentration 10%. Whereas, aqueous extract of Cinnamomum zeylanicum has no antibacterial activity against Proteus mirabilis.

The result involution graph of a finite group , denoted by is an undirected simple graph whose vertex set is the whole group and two distinct vertices are adjacent if their product is an involution element. In this paper, result involution graphs for all Mathieu groups and connectivity in the graph are studied. The diameter, radius and girth of this graph are also studied. Furthermore, several other graph properties are obtained.

The present work aims to analyze the evolution of the Moroccan tax system from the independence to the implementation of the tax reform of the 1980s in order to draw the lessons and to be able to decide on its future evolutions. Indeed, fiscal developments and "reforms" succeeded one another since the independence in 1956, with no significant evolution in the Moroccan tax system inherited from the French protectorate. Yet this system was characterized by imbalances; inconsistencies and inequities. A profound tax reform has become inevitable. After an undue delay; The Government has proceeded from 1984 to the reform of the effective tax system with a view to its modernization and simplification. This reform has resulted, in fact, in the passage of a heavy and complex schedular or analytical system, characterized by blatant inequalities, imbalances and inconsistencies to a modern and synthetic taxation system. At the end of this reform; three major synthetic taxes were set up: T.V.A, I.S and I.R. The reform also concerned the taxation of local authorities. With the implementation of the tax reform since 1984, the Moroccan tax system has certainly made progress but limitations related in particular to the architecture of the system and its structure and new synthetic taxes persist. Future research will focus on assessing the tax reforms and adjustments of the years 2000 and the prospects for reforming the Moroccan tax system.

Nocardia cyriacigeorgica (N. cyriacigeorgica) is most frequently associated with human infections, including chronic bronchitis, pulmonary disease and brain abscesses. In general, N. cyriacigeorgica causes infections in immunocompromised individuals and has been reported in clinical samples worldwide. However, the isolation and speciation of N. cyriacigeorgica in the routine diagnostic microbiology laboratory are complicated and time consuming. Recent mass spectrometry techniques such as matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry (MALDI-TOF-MS) have been successfully integrated into many routine diagnostic microbiology laboratories, allowing for the rapid, accurate and simple identification and speciation of many different microorganisms, including difficult-to-identify bacterial species. Here, we present a case report of a 65-year-old female patient from the neurology ward of Prince Sultan Military Medical City in Riyadh, Saudi Arabia, who was infected with N. cyriacigeorgica. The bacterium was successfully identified by MALDI-TOF-MS, with species identification subsequently confirmed by sequence analysis of the 16S ribosomal RNA.

Security of multimedia data is gaining acceptance owing to the growth and acceptability of images in various applications and in telecommunication. Encryption is one of the ways to ensure the security of images as they are used in many fields such as in secure medical imaging services, military intelligence, internet and intranet communication, e-banking etc. These images are stored or transmitted through a network; hence the security of such image data is important. In this work, recently developed encryption techniques are studied and analyzed to promote further development of more encryption methods to ensure additional security and versatility. All the techniques reviewed came into existence within the last five years (2011-2015) and are found to be useful for the present day encryption applications. Each technique is unique in its own way, which might be suitable for different applications. As time goes on, new encryption techniques are evolving. Hence, fast and secure conventional encryption techniques will always be needed in applications requiring high rate of security

This study examined assessment of the role of police community relations in crime prevention in
federal capital territory, 2009-2020. Community and police relationship stand as a paradigm shift that seeks
to focus on constructive engagement with people who are the end users of the police service and re – negotiate
the contract between the people and the police thereby making the community co – producers of justice and
a quality police service. The research is an assessment of police community relations in crime prevention in
the FCT. The spate of insecurity in the FCT is really alarming. The study reviewed relevant theoretical
framework and Empirical Review. Descriptive research design will be adopted in this study, the population
of study are 2,271 staff. To determine the sample size, Taro Yamane formula was adopted and questionnaire
were administered to respondents across all staff of Force Headquarters in Abuja, FCT Police Command.
Non-probability sampling technique was used in this study and therefore, simple percentages were used in
allocating questionnaire to the sampling units to reflect their population weights. Primary and secondary
sources of data were used in this study. The rationale for this is to ensure that adequate data is generated
for the study. Quantitative and qualitative methods of data analysis were adopted in this study. Quantitative
analysis was done using descriptive and correlation analysis. Chi-square analysis is adequate for test of
hypotheses because it is appropriate for the test of heterogeneous populations. Simple correlation coefficient
is adequate to test hypothesis 1 because it establishes association between two variables. Proportional
stratified random sampling is adequate because the sampling units are heterogeneous in character.
Therefore, the role of police community relation in crime prevention in Federal Capital Territory cannot be
overemphasized. In hypothesis one which is that: there is no significant relationship between police and
community in crime prevention in the FCT, the respondents are of the view there is no relationship between
the community and police in the FCT. Majority of the responded are optimistic that if the police continues to
relate and keep boosting the confidence of the community, the will continuously get the assistance of the
community in crime prevention. The Nigeria police are granted enormous powers by law and the constitution
to take preventive measures against the commission of all crimes in Nigeria. In this sense, the law allows
them to use such reasonable force as may be necessary for the prevention of crimes. In the exercise of this
authority, they have in various ways malevolently violated the rights of members of the public with impunity.
This practice has earned the Nigeria police different derogatory names, hatred and constant collision with
the members of the public to whom they sworn an oath to protect. Government should direct effort at dealing
with the cause of crime, that is, correction of the conditions that make crime a valuable alternative to law
abiding behaviour. Government should also ensure jobs are made available for the teeming population of
school leavers of all categories to forestall the probability of some of these joining criminal gangs.

Deep Learning (DL) models have outperformed remarkably and effectively on several Computers Vision applications. However, these models require large amounts of data to avoid overfitting problems. Overfitting happens when a network trains a function with an incredibly high variance to represent the training data perfectly. Consequently, medical images lack to availability of large labeled datasets, and the annotation of medical images is expensive and time-consuming for experts, as the COVID-19 virus is an infectious disease, these datasets are scarce and it is difficult to get large datasets. The limited amount of the COVID-19 class compared to any other classes, for example (healthy). To solve the scarcity data problem, we adjust a Conditional Generative Adversarial Network (CGAN) as a solution to the problems of scarcity and limited data. CGAN contains two neural networks: a generator that creates synthetic (fake) images, and a discriminator that recognizes a real sample of training and a generated sample from the generator. The adjusted CGAN is able to Generate synthetic images with high resolution and close to the original images which aid in expanding the limited dataset specific to a new pandemic. In addition to CGAN augmenting strategies, this research also briefly explores additional aspects of data augmentation like time augmentation and total dataset size. Frechet inception distance metric (FID) has been used for evaluating synthetic images generated by CGAN. The adjusted CGAN obtains better FID results for the high-resolution synthetic X-rays images it achieves 2.349%.

Polluted water has been considered a critical issue nowadays, threatening the environment and lives of living creatures. Because of technological and industrial advancements, as well as increased social activities of humans in various countries, pollution sources have multiplied. To reduce the impact of this problem, many techniques have been developed in order to reach zero discharge pollution. In the last decade, graphene oxide (GO) - a member of the graphene nanomaterials family, has been the focus of many research efforts in the water treatment sector because of its extraordinary properties. This review highlights the research efforts conducted to investigate GO as a novel adsorbent for water treatment applications and recent fulfilments in the last 3 years. The synthesis techniques, properties, and efficiency of this material in water treatment will be explained. All results confirm the future role of GO as an efficient absorbent to solve wastewater purification challenges, but the big challenge is to reduce time and simplify the complicated extent of synthesis stages, besides reducing the high cost of production methods. According to the review, Iraqi researchers' efforts to use this nanomaterial in water purification are still in their early stages.

Fluctuations in oil prices have caused economic contractions and challenges to oil-exporting economies. In particular, Nigeria suffers both the previous and current global oil price shocks and this has raised concerns among policymakers, governments, and economic analysts because of the impact of oil and oil prices in Nigeria's macroeconomic development. However, this paper investigates the role of diversification on economic growth in Nigeria using annual data from 1986 to 2018. The techniques applied showed that only remittances and official development assistance have affected economic growth in the short run. However, the coefficients of one period lagged indicated that the system is capable of adjusting to its long-run equilibrium condition after some shocks in the system. The findings from variance decomposition indicated that diversification plays a positive role on economic growth in both the short and long-run horizons. By overall implication, the study concludes that diversification has a positive role on Nigeria's economic growth. Therefore, the study recommends the need for the government to provide active and inclusive policies such as soft loans and commercial agricultural programs to improve its export of agricultural output competitiveness, improve supervisory and regulatory frameworks in the financial sector to ease remittances inflow. For these reasons, diversifying the economy from oil revenue is the ultimate goal for achieving sustainable economic growth and development goals or targets by the year 2030.

Abstract Increasing demands for ultrahigh-strength steels in commercial as well as military applications have raised interest in finding alternatives to the high-cost high-alloyed steel and super-alloys currently used, e.g. the use of economic low-alloy compositions processed via low-cost air induction melting and electroslag refining (ESR). In this work the yield of alloying elements and the removal of the impurities nitrogen, sulphur and phosphorus as a result of electroslag refining (ESR) in a newly developed CrNiMoWMnV ultrahigh-strength steel (UHSS) have been studied in relation to their activities in the molten metal pool. Six experimental heats of CrNiMoWMnV UHSS with different chemical compositions were designed, melted in an induction furnace (IF) and refined using ESR. This was followed by hot forging of the ingots at 1100˚C to 950˚C. ESR using a CaF₂-CaO-Al₂O₃ slag system led to a high yield in Cr, Ni, Mo, W, Mn and V, while the yield of Si is low. The desulphurization of all six UHSS grades was pronounced with most of the sulphur removed either to the slag or by gas reactions. The degree of dephosphorization was only 5% irrespective of the steel composition. On the other hand, denitrification (removal of nitrogen) was achieved. It ranged from 8% to 63% depending on the steel composition. The yield of the alloying elements and removal of impurities from the steel during ESR depends on the chemical and physical properties of the ESR slag and the activity of the elements in the molten state, taking into account elemental interactions.

Security of multimedia data is gaining acceptance owing to the growth and acceptability of images in various applications and in telecommunication. Encryption is one of the ways to ensure high security of images as they are used in many fields such as in secure medical imaging services, military intelligence, internet and intranet communication, e-banking etc. These images are stored or transmitted through a network; hence the security of such image data is important. In this work, recently developed encryption techniques are studied and analyzed to promote further development of more encryption methods to ensure additional security and versatility. All the techniques reviewed came into existence within the last five years (2011-2015) and are found to be useful for the present day encryption applications. Each technique is unique in its own way, which might be suitable for different applications. As time goes on, new encryption techniques are evolving. Hence, fast and secure conventional encryption techniques will always be needed in applications requiring high rate of security.