Muslim Women’s Right to Divorce and Gender Equality Issues in Bangladesh: A Proposal for Review of Current Laws

In Bangladesh, sharia law goes hand in hand with the statutory laws of the land. These laws are both conjointly used to regulate and monitor the issues of divorce among Muslims of the country. Orthodox Islamic laws provide husbands with the authority of issuing divorce or talaq to their wives known as Talaq-e-Tawfiz (popularly known as tawfiz) in the kabinnama (the written document of the contract of marriage). Women’s power to exercise the tawfiz, however, depends solely on the will of their husbands. Although Muslim women are capable of repudiating their marriages by the process of khula or mubarat, these are only executable under the free consent of their husbands. Also, the statutory laws of Bangladesh address Muslim women’s right to the dissolution of marriage by the intervention of the court, only under several grounds. The traditional interpretation of sharia law and the statutory laws of the country are both unwilling to establish Muslim women’s absolute right to renounce marriage as with their male counterparts. Current research reveals that this violation of gender equality and women’s rights generates female subordination in society and gives birth to numerous socio-legal complications

Scrub typhus in India: Whether increased reporting or expanding geographies?

Scrub typhus is a potentially fatal disease with serious complications in untreated cases or where there is delay in starting treatment. It has been considered to be limited to certain geographic areas with vegetations and cattle grazing fields like Jammu. Scrub typhus cases/outbreaks have been reported in the recent past from South India, Mumbai, Goa, Himachal Pradesh, and Haryana. Recently, we had a case of scrub typhus in a child residing in Delhi with no history of travel outside. A 10-year-old girl admitted with high-grade fever, abdominal pain, myalgia, and erythematous rash with hepatomegaly but without lymphadenopathy and developed splenomegaly in the 2nd week of illness. She was confirmed to be a case of scrub typhus after immunoglobulin M enzyme-linked immunosorbent assay for the disease. Scrub typhus is a matter of great public health importance that all medical practitioners should be sensitized about this disease and its varying presentations and complications

Development of an artificial neural network algorithm for predicting the surface roughness in end milling of inconel 718 alloy

In this work, an artificial neural network (ANN) model was developed for the investigation and prediction of the relationship between cutting parameters and surface roughness during high speed end milling of nickel-based Inconel 718 alloy. The input parameters of the ANN model are the cutting parameters: cutting speed, feed, and axial depth of cut. The output parameter of the model was surface roughness. For this interpretation, advantages of statistical experimental design technique, experimental measurements, artificial neural network were exploited in an integrated manner. Cutting experiments are designed based on statistical three-level full factorial experimental design technique. A predictive model for surface roughness was created using a feed-forward back-propagation neural network exploiting experimental data. The network was trained with pairs of inputs/outputs datasets generated when end milling Inconel 718 alloy with single-layer PVD TiAlN coated carbide inserts. A very good predicting performance of the neural network, in terms of concurrence with experimental data was attained. The model can be used for the analysis and prediction for the complex relationship between cutting conditions and the surface roughness in metal-cutting operations and for the optimization of the surface roughness for efficient and economic production

Enhancement of machinability of Inconel 718 in end milling through online induction heating of workpiece

This paper presents the outcome of a study on heat assisted end milling of Inconel 718 using inducting heating technique conducted to enhance the machinability of the material. The heating temperature maintained below the phase transformation temperature was aimed at softening the top removable material layers. The experimental results of both conventional and heat assisted machining were compared. The machinability of Inconel 718 under these conditions was evaluated in terms of tool life, tool wear morphology and chatter. The advantages of Induction heating is demonstrated by an longer tool life and lower chatter. The study showed that preheated machining facilitates up to 80% increase of tool life over conventional machining conducted using TiAlN coated carbide inserts

Influence of chip serration frequency on chatter formation during end milling of Ti6Al4V

This paper includes the findings of an experimental study on instabilities of the chip formation process during end milling of Ti6Al4V alloy and the influence of these instabilities on chatter formation. It has been identified that the chip formation process has a discrete nature, associated with the periodic shearing process during machining. The chip formed during machining of titanium alloy Ti6Al4V is found to be mainly with primary serrated teeth appearing in the main body of the chip. Secondary serrated teeth resulting from the coagulation of a certain number of primary serrated teeth also happen to appear at the free or constrained edge of the chip, especially when the system enters into chatter. In order to identify the interaction of these chip instabilities with the prominent natural vibration of the machine tools system components, the different mode frequencies of the vibrating components of the system have been identified using experimental and finite element modal analyses, and vibration responses during actual cutting have also been recorded using an online vibration monitoring system. The vibration signals in frequency domain (fast Fourier transform) have been analyzed to identify the chatter frequencies and the peak amplitude values. Chatter was found to occur at two dominant mode frequencies of the spindle. These mode frequencies at which chatter occurred have been compared with the chip serration frequencies in a wide cutting speed range for different conditions of cutting. It has been concluded from these findings that chatter occurs during end milling due to the resonance of the machine tools system component when the frequency of primary serrated teeth formation is approximately equal to the "prominent natural frequency" modes of the system components, which are the two mode frequencies of the VMC machine spindle in this particular case

Enhancement of machinability by workpiece preheating in end milling of Ti-6Al-4V

Purpose: The main objective of this paper is to investigate the effect of workpiece preheating with high frequency induction heating on improvement of machinability of Ti-6Al-4V during end milling using PVD TiAlN coated inserts. Tool life, cutting force and vibration were investigated during the experiments. Design/methodology/approach: End milling tests were conducted on Vertical Machining Centre (VMC ZPS, Model: MCFV 1060 with quarter immersion cutting. Titanium based alloy Ti-6Al-4V bar was used as the work-piece. Machining was performed with a 20 mm diameter end-mill tool holder (R390-020B20-11M) fitted with one insert. PVD TiAlN coated carbide inserts (R390-11 T3 08E-ML 2030) were used in the experiments. All of the experiments were run at room temperature and preheated conditions. The preheated temperature was maintained at 420ºC and no phase change of the workpiece in preheating was ensured from the phase diagram of Ti-6Al-4V. High frequency induction heating was utilized to run the preheated machining. Findings: Preheating helps in substantially increasing tool life and in lowering down the cutting force value, lowering the amplitude of vibration and dynamic forces. Practical implications: The cost of machining Ti-6Al-4V is extremely high because of the relatively low machining speed and short tool life. Therefore, improving the machinability of Ti-6Al-4V is a research topic of much interest, with a number of approaches reported with varied results, such as, cryogenic cutting, highpressure coolant, rotary-tool, and minimum quantity lubrication (MQL). Originality/value: A new approach of induction preheating to overcome the difficulties in machining of Ti-6Al-4V is presented in this paper. In preheated machining, high frequency induction heating is used as an external heat source to soften the work material surface layer in order to decrease its tensile strength and strain hardening. An experimental study has been performed to assess the effect of workpiece preheating using induction heating system to enhance the machinability of Ti-6Al-4V. The preheating temperature was maintained below the phase change temperature of Ti-6Al-4V

Control of sulphur and minimisation of centre line segregation for Rail Steel

Rail is the most important constituent of the track structure and plays a very vital role in the reliability of railway system as a whole. Quality of rail steel with reference to its chemical composition has been a matter of prime importance for the manufacturers as well as Railways. Sulphur is a detrimental element in rails since it causes hot shortness during rolling, centerline segregation during casting, poor weldability for the rails etc. To improve quality of rails, a substantially low range of sulphur < 0.015% (Railway's specified norms <0.03%) has been targeted in Bhilai Steel Plant by adequate sulphur control measures in steelmaking process. A two stage desulphurisation treatment is now employed in which the blast furnace hot metal is first treated by co-injection of Mg and CaC reagents, and subsequent treatment with a 2 synthetic slag former (CaO-Al O ) added to the ladle during tapping from the Basic 2 3 Oxygen furnace. Improvement in the internal quality of the cast bloom has been established by introduction of Electro Magnetic Stirring. The centerline segregation is minimized vis-a-vis the properties of the cast product and rails improved by the successful implementation of step by step control measures

Enhancement of machinability of nickel based alloy - inconel 718 by induction preheating in end milling using ceramic inserts

Unique combinations of high strength properties maintained at elevated temperature and high resistance to chemical degradation have made Nickel based alloy, Inconel 718 suitable for application as aerospace components. However, the same properties are responsible for very poor machinability of the material, as Inconel is one of the most difficult to cut materials. The main reason for poor machinability is generation of high heat during machining which lead to premature failure of the tool due to plastic deformation and diffusion. Uncoated and coated tools have been found to be not efficient in cutting this materials and the application of preheated resulted in not significant improvement in their machinability. PCD tools are not recommended for machining this material since it contains iron which acts as a catalyst to convert diamond into graphite at temperatures in excess of 700 0C. PCBN tools are very costly and also did not show very good performance in machining Inconel 718. Ceramic tools have proved to have performed well in machining the material. However, there was so far no work performed performance of ceramic tools in machining Inconel 718 using preheated technique. Since ceramic tools can perform under high temperatures, it was expected that preheated machining using ceramic tools would desired results. In this research work induction heating technique in combination of the application of ceramic tools was adopted as one of the machining techniques in order to improve the machinability of the material. The effect of preheated machining of Inconel 718 has been analyzed in terms of tool wear, surface roughness and chip formation. The advantages of preheated machining are demonstrated by appreciable increase in tool life, better surface roughness values and improved chip formation compared to room temperature machining

Development of a cost effective technique to eliminate conventional finishing operation applying high speed end milling of silicon

Silicon has been widely used in different branches of industrial engineering. Most application of silicon is in computer parts or hardware especially for the production of integrated circuit (IC) chips. Machining of silicon is a big challenge and expensive affair because of it inherent brittleness which is a major limitation as the process of removing the material can generate subsurface damage. Silicon is conventionally finished using grinding followed by polishing and lapping to achieve required surface finish and surface integrity..