Application of Machine Learning Approaches in Intrusion Detection System

The rapid development of technology reveals several safety concerns for making life more straightforward. The advance of the Internet over the years has increased the number of attacks on the Internet. The IDS is one supporting layer for data protection. Intrusion Detection Systems (IDS) offers a healthy market climate and prevents misgivings in the network. Recently, IDS is used to recognize and distinguish safety risks using Machine Learning (ML). This paper proposed a comparative analysis of the different ML algorithms used in IDS and aims to identify intrusions with SVM, J48, and Naive Bayes. Intrusion is also classified. Work with the KDD-CUP data set, and their performance has checked with the Weak software. In comparison of techniques such as J48, SVM and Naïve Bayes showed that the accuracy of j48 is the higher one which was (99.96%)

Electrical charactrization of III-V antimonide/GaAs heterostuctures grown by Interfacial Misfit molecular beam epitaxy technique

Lattice mismatched heterostructures grown by Interfacial Misfit (IMF) technique, which allows the strain energy to be relieved both laterally and perpendicularly from the interfaces, are investigated. However, electrically active defects are created at the interface and away from the interface with energy levels deep in the bandgap of the host materials. These defects dramatically affect the optical and electrical properties of the devices. In this thesis, an investigation of deep level defects is carried out on GaSb/GaAs uncompensated and Te compensated heterostructures grown by the IMF method using DLTS, Laplace DLTS, I-V, C-V, C-F and C-G-F measurements. Furthermore, the effect of thermal annealing treatments on the defect states is also studied on both types of samples. It was found that the well-known EL2 electron trap is commonly observed near to the interface of both uncompensated and Te compensated GaSb/GaAs IMF samples. However, several additional electron defects are detected in Te compensated samples. Rapid thermal annealing performed on uncompensated samples resulted in the annihilation of the main electron trap EL2 at a temperature of 600 oC. On the other hand rapid thermal annealing and conventional furnace annealing were carried out on Te compensated samples, and it was observed that rapid thermal annealing process is more effective in terms of defects reduction. The density of interface states is determined from C-G-F and forward bias DLTS measurements. Te compensated samples exhibit the highest density of interface states and have additional hole traps as compared to uncompensated samples. The electrical properties of p-i-n GaInAsSb photodiodes grown on uncompensated and Te compensated GaSb/GaAs templates on GaAs substrates using special growth mode are investigated. The non-radiative defects which could have detrimental effects on the performance of these photo diodes are studied here for the first time. Both electron and hole defects are detected, and their capture cross-section measurements reveal that some of defects originate from threading dislocations. The double pulse DLTS measurements are performed and the concentration distributions of the detected defects are determined

The British Art of Colonialism in India: Subjugation and Division

This article utilizes a three-pronged analytical model to examine the mechanics of British colonialism and its socioeconomic and political consequences in India. Those three elements are divide and rule, colonial education, and British laws. The British took some reformative initiatives that ostensibly deserve appreciation such as the development of a predictable legal system, investment in infrastructure development, and education in the late nineteenth and mid-twentieth centuries. However, most colonial policies and reforms were against the will and welfare of the people of India. The British took away India’s resources and introduced the English educational system to create an educated and elite buffer class for its own interests. It also introduced positivistic and predictable laws and repressive and discriminatory measures, including force, to control the natives and prevent anti-British agitation, protests, and armed uprisings in India. Although the consequences of British colonialism in India has been explored from various disciplines, the legacy of British colonialism to present day Bangladesh, India, and Pakistan has not been examined from the Peace and Conflict Studies (PACS) lens. Johan Galtung’s (1990) violence triangle framework helps us to understand the different forms of colonial violence, and the need for positive peacebuilding in the post-colonial context. This paper argues that the current educational policy, the legal framework, and the ethno-religious-cultural diversity of today, exhibiting the structural, cultural, and direct violence, are a continuation of the legacy of the British Raj

A new monolithic approach for mid-IR focal plane arrays

Antimonide-based photodetectors have recently been grown on a GaAs substrate by molecular beam epitaxy (MBE) and reported to have comparable performance to the devices grown on more expensive InSb and GaSb substrates. We demonstrated that GaAs, in addition to providing a cost saving substrate for antimonide-based semiconductor growth, can be used as a functional material to fabricate transistors and realize addressing circuits for the heterogeneously grown photodetectors. Based on co-integration of a GaAs MESFET with an InSb photodiode, we recently reported the first demonstration of a switchable and mid-IR sensible photo-pixel on a GaAs substrate that is suitable for large-scale integration into a focal plane array. In this work we report on the fabrication steps that we had to develop to deliver the integrated photo-pixel. Various highly controllable etch processes, both wet and dry etch based, were established for distinct material layers. Moreover, in order to avoid thermally-induced damage to the InSb detectors, a low temperature annealed Ohmic contact was used, and the processing temperature never exceeded 180 °C. Furthermore, since there is a considerable etch step (> 6 μm) that metal must straddle in order to interconnect the fabricated devices, we developed an intermediate step using polyimide to provide a smoothing section between the lower MESFET and upper photodiode regions of the device. This heterogeneous technology creates great potential to realize a new type of monolithic focal plane array of addressable pixels for imaging in the medium wavelength infrared range without the need for flip-chip bonding to a CMOS readout chip

Electrical charactrization of III-V antimonide/GaAs heterostuctures grown by Interfacial Misfit molecular beam epitaxy technique

Lattice mismatched heterostructures grown by Interfacial Misfit (IMF) technique, which allows the strain energy to be relieved both laterally and perpendicularly from the interfaces, are investigated. However, electrically active defects are created at the interface and away from the interface with energy levels deep in the bandgap of the host materials. These defects dramatically affect the optical and electrical properties of the devices. In this thesis, an investigation of deep level defects is carried out on GaSb/GaAs uncompensated and Te compensated heterostructures grown by the IMF method using DLTS, Laplace DLTS, I-V, C-V, C-F and C-G-F measurements. Furthermore, the effect of thermal annealing treatments on the defect states is also studied on both types of samples. It was found that the well-known EL2 electron trap is commonly observed near to the interface of both uncompensated and Te compensated GaSb/GaAs IMF samples. However, several additional electron defects are detected in Te compensated samples. Rapid thermal annealing performed on uncompensated samples resulted in the annihilation of the main electron trap EL2 at a temperature of 600 oC. On the other hand rapid thermal annealing and conventional furnace annealing were carried out on Te compensated samples, and it was observed that rapid thermal annealing process is more effective in terms of defects reduction. The density of interface states is determined from C-G-F and forward bias DLTS measurements. Te compensated samples exhibit the highest density of interface states and have additional hole traps as compared to uncompensated samples. The electrical properties of p-i-n GaInAsSb photodiodes grown on uncompensated and Te compensated GaSb/GaAs templates on GaAs substrates using special growth mode are investigated. The non-radiative defects which could have detrimental effects on the performance of these photo diodes are studied here for the first time. Both electron and hole defects are detected, and their capture cross-section measurements reveal that some of defects originate from threading dislocations. The double pulse DLTS measurements are performed and the concentration distributions of the detected defects are determined

Multispectral mid-infrared light emitting diodes on a GaAs substrate

We have designed, simulated, and experimentally demonstrated four-colour mid-infrared (mid-IR) Light Emitting Diodes (LEDs) integrated monolithically into a vertical structure on a semi-insulating GaAs substrate. In order to finely control the peak wavelength of the emitted mid-IR light, quantum well (QW) structures based on AlInSb/InSb/AlInSb are employed. The completed device structure consists of three p-QW-n diodes with different well widths stacked on top of one bulk AlInSb p-i-n diode. The epitaxial layers comprising the device are designed in such a way that one contact layer is shared between two LEDs. The design of the heterostructure realising the multispectral LEDs was aided by numerical modelling, and good agreement is observed between the simulated and experimental results. Electro-Luminescence measurements, carried out at room temperature, confirm that the emission of each LED peaks at a different wavelength. Peak wavelengths of 3.40 μm, 3.50 μm, 3.95 μm, and 4.18 μm are observed in the bulk, 2 nm, 4 nm, and 6 nm quantum well LEDs, respectively. Under zero bias, Fourier Transform Infrared photo-response measurements indicate that these fabricated diodes can also be operated as mid-IR photodetectors with an extended cut-off wavelength up to 4.6 μm

ROLE OF THYMECTOMY IN MYASTHENIA GRAVIS

Thirteen patients with myasthenia gravis underwent total thymectomy between January, 1988 and December, 1991. The duration of symptoms prior to surgery varied from 2 months to 20 years. In a follow-up ranging from 2 months to 4 years, 11 patients showed a significant improvement with either complete discontinuation of medication of a marked reduction in doses. One patient with a small benign thymoma showed some improvement but subsequently required stepping up of anticholinesterase medication and addition of steroids and immune suppressants; another patient with atrophic thymic tissue had complete remission after thymectomy but developed myasthenic symptoms six months later requiring medication again. Thymectomy is recommended for all patients with generalised myasthenia gravis with or without thymoma regardless of the duration of disease unless the patient is a very high risk candidate for surgery. It is not recommended for isolated ocular myasthenia gravis. (JPMA 42:107, 1992)

Burden of antibiotic resistance among children with typhoid in Gadap Town, Karachi, Pakistan

Background: Increasing antibiotic resistance by pathogenic bacteria is observed in poor sanitary conditions. The peak incidence of typhoid occurs between 5–15 years of age. This is the most common bacteraemic illness of children in Pakistan. The aim of this study was to investigate the frequency of drug-resistant SalmonellaTyphi and S. Paratyphi A in children hospitalized or treated as outpatients at a tertiary care centre that serves Gadap Town, an extensive slum district of Karachi. Methods: A total of 275 peripheral blood samples were collected from children up to 14 years old who presented with clinical features of typhoid to Fatima Hospital, Baqai Medical University, over a two-year period. Samples were cultured for growth of aerobic and facultative anaerobic bacteria, identified by biochemical reactions. Antimicrobial susceptibility was tested by Kirby-Bauer disc diffusion using eight different antibiotics. Results: Among all samples, 30 (10.9%) were positive for S. Typhiby blood culture. The rate of positivity was 23 (76.7%) cases for ages 5–14 years, three (10.0%) in each of age groups 2.0–2.9 and 4.0–4.9 years, and one patient (3.3%) aged 3.0–3.9 years. The majority of S. Typhi isolates were resistant to co-trimoxazole (66.7%), ampicillin (63.3%), nalidixic acid (60.0%), chloramphenicol (50.0%) and aztreonam (50.0%). However, most isolates were susceptible to ceftriaxone (76.7%) and ciprofloxacin (66.7%). There were 15 multidrug-resistant isolates but no typhoid-related deaths. Conclusion: Our findings show evidence of antimicrobial resistance by S. Typhiisolated from Karachiite children living in a poverty-stricken setting where water quality and sanitation are both unsatisfactory. Currently, Pakistan’s most populated city is recognized as a focus of typhoid cases. Therefore, this first report of the emergence of confirmed cases of multidrug-resistant S. Typhi from the only public hospital in its largest neighborhood identifies a grave public health concern