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What is Hacking?Acts intended at exploiting digital devices such as computers, cellphones, tablets, and even entire networks are referred to as hacking.While hacking isn't always for malicious purposes, most references to it (and hackers) nowadays define it (and them) as illicit cybercriminal behaviour motivated by monetary gain, protest, information collecting (spying), or even just for the "fun" of it.How Hacking Works?Hacking is usually technical in nature. However, hackers can utilise psychology to persuade a user to open a harmful file or provide sensitive information. "Social engineering" is the term for these techniques. Besides social engineering and malvertising, common hacking techniques ... Read More
The worldwide video game business is prospering despite the economic upheaval created by the coronavirus. Individuals are resorting to virtual worlds for escapism from the crisis as social alienation reduces physical connection to a minimum and encourages people to stay at home. In March, video game sales in the United States reached their highest level in almost a decade, and gaming industry behemoths have all reported a significant growth in user numbers.Online Gaming Safety TipsFor any purchases relating to the game, only utilise the official websites. Clicking on links that take you to third-party websites is not a good idea.Don't ... Read More
In our daily lives, we use many physical measurements to identify the people around us, be it the sound of a person, his fingerprint, or anything. It is a unique character that allows us to identify the person. The science of identifying a person using these physical and behavioral measurements and analyses is called Biometrics.Let us now see more on Biometrics and how it works.What is Biometrics?From unlocking our smartphones to unlocking our bank locker, Biometrics plays a vital role in our lives as it is a much more secure way than other methods of access control such as keys, ... Read More
The practice of defending oneself from being tricked into online scams is known as online fraud protection.Online users can protect themselves from hazardous malware or hacking efforts to obtain personal information that cybercriminals use for their financial benefit by educating themselves and downloading reliable and up-to-date anti-virus software. Nowadays, as more fraudulent activities occur, many anti-fraud protection services are also being developed, discussed below.What are Credit Monitoring Services?Credit monitoring is a service that studies and monitors your credit reports at all times. They even monitor your credit scores, detect any unusual activity, and report it as soon as it is ... Read More
What is a VPN, and is it legal or not?A VPN is one of the most dependable and secure ways to safeguard your devices, and it was designed specifically for use with public WiFi. A virtual private network (VPN) connects users' devices to a private network over a public network. VPNs protect your internet connection by acting like a bulletproof vest. They preserve your privacy, enabling private and anonymous web browsing and encrypting the data sent through that connection.Even though VPNs have numerous advantages and are typically lawful, they are prohibited in several countries. But don't worry, using a VPN ... Read More
Mechanism of Train MovementThe essential mechanism of an electric locomotive is shown in the figure below.Here, the armature of the driving motor has a pinion of the diameter d1 attached to it. The tractive effort at the edge of the pinion is transferred to the driving wheel by means of a gearwheel.Let, T = Torque exterted by the motor in NmF1 = Tractive effort at the pinionFt = Tractive effort at the wheel$\gamma $ = Gear ratiod1 = Diameter of piniond2 = Diameter of gear wheelD = Diameter of driving wheel$\eta $ = Efficiency of power transmission from motor to ... Read More
There are two types of AC system of track electrification −Single-Phase Low-Frequency AC System (15 kV to 25 kV at 16$\frac{2}{3}$ Hz, 25 Hz and 50 Hz)Three-Phase AC System (3.3 kV to 3.6 kV at 16$\frac{2}{3}$ Hz)Single-Phase Low-Frequency AC SystemIn a single-phase low-frequency system of track electrification, an AC voltage of 15 kV at a frequency of 16$\frac{2}{3}$ to 25 Hz is used.The use of high voltage AC in the system reduces the current flowing through the overhead transmission line resulting in the reduced voltage drops and it helps in installing the substations at larger distances, about 50 to 80 ... Read More
The speed-time curve of a main line service is best and most easily replaced by trapezoid. The figure shows the simplified trapezoidal speed-time curve for the main line service.Let, $\mathit{V_{m}}$ = Crest speed in kmph$\alpha$ = Acceleration in kmphps$\beta$ = Retardation in kmphpsT = Total time of run in seconds$\mathit{t_{\mathrm{1}}}$ = Acceleration time in seconds$\mathit{t_{\mathrm{2}}}$ = Free running time in seconds$\mathit{t_{\mathrm{3}}}$ = Retardation time in secondsD = Total distance of run in kmTherefore, the time of acceleration in seconds is given by, $$\mathrm{\mathit{t_{\mathrm{1}}}\:=\:\frac{\mathit{V_{m}}}{\alpha }}$$And the time for retardation in seconds is, $$\mathrm{\mathit{t_{\mathrm{3}}}\:=\:\frac{\mathit{V_{m}}}{\beta }}$$Hence, the time for free running in seconds is, ... Read More
For urban and suburban services, the simplified quadrilateral speed-time curve of electric traction is shown in the figure.Let, $\alpha$ = Acceleration in kmphps$\beta$ = Braking retardation in kmphps$\beta_{c}$ = Coasting retardation in kmphpsV1 = Maximum speed at the end of acceleration in kmphV2 = Speed at the end of coasting in kmphT = Total time of run in secondst1 = Acceleration time in secondst2 = Coasting time in secondst3 = Braking time in secondsD = Total distance travell in kmTherefore, the time of acceleration is given by, $$\mathrm{\mathit{t_{\mathrm{1}}}\:=\:\frac{\mathit{V_{\mathrm{1}}}}{\alpha } }$$The time of coasting is given by, $$\mathrm{\mathit{t_{\mathrm{2}}}\:=\:\frac{\mathit{V_{\mathrm{1}}}-\mathit{V_{\mathrm{2}}}}{\beta_{c} } \:\:\:\cdot \cdot ... Read More
Crest Speed of Electric TrainThe maximum speed attained by an electric train during running is termed as its "crest speed". It is denoted by Vm.Average Speed of Electric TrainAverage speed is defined as the mean of the speeds attained by the electric train from start to stop. In other words, average speed is defined as the ratio of the distance covered by the train between two stops to the actual time of run. The average speed of train is denoted by Va and is given by, $$\mathrm{\mathrm{Average\: speed, }V_{a}\:=\:\frac{\mathrm{Distance\: between \:two\: stops\: (\mathit{D})}}{\mathrm{Actual\: time\: of\: run (\mathit{T_{\mathrm{run}}})}}\:\mathrm{kmph}}$$Schedule Speed of Electric ... Read More