Archive for December 2016

Problems Faced By Indian Engineering Students Today :

 

 

One of the major problems millions of engineering graduates face in India today, ………is that there are way too many engineering graduates in India. Chronic unemployment has become an embarrassing issue, plaguing the engineering sector. One of the main reason for this persistent problem of unemployment among the young engineers is that there are way too many engineers in India.

The basic rule of economics demand versus supply applies here, the supply of engineering graduates, far exceed the demand (number of engineering jobs). So thousands of engineering graduates face an uncertain future by the time they graduate. Many engineers due to the lack of jobs often engage in professions which have very little to do with engineering like peon work, bank PO ( probationary officer), school teacher, BPO etc. This article addresses the ever growing problem of chronic engineering unemployment and will also share some tips on how to ameliorate this issue to some extent.

Lack of Practical Experience : This is in fact the crux of the problem. Every year a huge number of students graduate are just pen and paper engineers, – lots of theoretical knowledge with zero practical experience. Apart from the Tier 1 engineering colleges, most of the Tier 2 and 3 engineering are heavy on academics but give very little significance to practical learning or hands on training. There are little to no internships , industry visits etc. Students have almost zero industry experience, and their knowledge is limited to the books they have studied. There are too many CS engineers for example who don’t know how to programme and code efficiently.

Solution : The engineering colleges need to make the syllabus more profession or job oriented. With rigorous academics regular industry interfaces, and at least 3 internships should be introduced.

Outdated Syllabus : Unfortunately majority of the second and third tier engineering colleges follow an out of date syllabus. The students are not well versed in latest softwares, technologies prevalent in the industries. Obviously most of the IT firms are reluctant to hire such engineers who lack knowledge of in demand technologies. The companies consider these graduates a liability as lot of time and money have to spent in training them. According to reports most of the engineering graduates are unemployable. Many CS/IT students are virtually incapable of ensuring security in C code, and lack basic programming skills.

Solution : Update syllabus ASAP. Make the syllabus not exam oriented but industry oriented. Include advanced programming languages like Java, C, C++, Python, Ruby on Rails, etc

Curse of Rote Learning : The Indian engineering education system is exam oriented. Most of the 2nd and 3rd tier colleges discourages innovation and research, The students are made to quickly mug up thick tomes/books without understanding basic engineering concepts. Majority of the students study solely to get marks/pass exam and lack in depth understanding of basics of engineering.

Solution : Encourage more research and innovation in engineering institutes

Disinterested Students : Engineering after medical studies are considered by Indian parents as lucrative. Engineering courses are thought to be as ticket to higher pay packages in corporate world. Driven by this mistaken thought many middle class parents in India induce/force their . children to study engineering. Students who are not at all interested in the subject, take it up to pacify parents or due to peer pressure. As they are studying a subject they have little to no interest in, they yield average to below average results.

Solution : Education should be interest and aptitude oriented and not job oriented.

 

 

Waste-to-energy combustion

The history of combustion of solid wastes in the United States clearly demonstrates the controversial nature of this method of waste disposal. In 1960, a little over 30 percent of Municipal solid waste discards was burned in incinerators solely as a volume reduction practice. That percentage dropped rapidly during the 1960s and 1970s, reaching a low of less than 10 percent in 1980.

 

With increased emphasis on avoiding landfilling and with better incinerators that were designed to control emissions while generating useful steam or electricity, combustion of municipal solid waste has reached about 15 percent of municipal solid waste generation. A number of developed countries around the world rely heavily on incineration than does the United States, especially if they have high population densities. Japan , for instance , burn almost two thirds of its waste , while the incineration rate in Western Europe is roughly 30 to 40 percent.

 

     In the early 1990s , the United States had 190 municipal solid waste combustion facilities in operation that burned about 30 million tons of waste per year. By 2000, that number had dropped to 102 , and by 2015, it was down to 88. Those 88 facilities, however, were bigger and cleaner and they burnt more waste than those in operation in the early 1990s. Most of these are located in the Northeast and South, while the west has only half a dozen.

 

Incineration of  municipal solid waste as a method of disposal has a number of favourable attributes, including volume reduction, immediate disposal without waiting for slow biological processes to do the job, much less land area requirements, destruction of hazardous materials , and the possibility of recovering useful energy. There are also tradeoffs, for example, it is reasonable to question whether burning paper for its energy value, or recycling it to reduce the environmental impacts of virgin pulping is the best way to utilize the material.

 

On the negative side of combustion, poorly operated incinerators release toxic substances such as dioxins into the air. The ash recovered may be classified as hazardous material that requires special technological handling. Unfortunately, the public is generally reluctant to accept new technological innovations, especially if a facility is being proposed in their own area. There is also a concern for whether incineration is compatible with recycling. Once an incinerator has been built, a consistent pile of refuse must be maintained to pay it off.

 

There can be reluctance to expand a recycling program if it may reduce the fuel supply, and hence cash flow for the incineration system. In the general hierarchy of solid waste management, recycling is considered a better than incineration. So there are advocates who feel it is important to write into an incineration contract, the freedom to reduce the amount of garbage are provided any time, without penalty or other economic risk, when that reduction is due to an expansion in recycling.

Welding of wood

Have you ever wondered how to join two pieces instead of using glue? Say for example, can you join two pieces of wood to make it appear as a single piece? The answer lies in the fine craftsmanship of a mechanical engineer who knows the emerging science of “mechanically-induced wood flow welding” pretty well. Now to “weld” wood, which is quite a promising technology, you need to force pieces of lumber together by pressing (at 60 – 330 psi) and rubbing the parts to-and-fro at a very high speed for 4 to 5 seconds. The friction created in between the pieces heats and melts the primary components of wood, lignin and fibers present on the exposed surface. In the next few seconds, the molten lignin of both the surfaces intertwines in a matrix and finally solidifies when the friction movement is stopped and the interface cools down. It results in the formation of a full piece of wood of desired shape and size.

Laboratory for Timber Construction IBOIS of Ecole Polytechnique (EPFL), Switzerland applied the principle of friction welding to weld wood for the first time. The University of Tennessee has also been exploring the same area. Their research is mainly focused on the fabrication and application of welded timber panels. The research work has produced small-scale welded wooden samples successfully. Those samples have gone through tests of bending and shear-giving and have yielded positive results. Here it should be noted that the structural design of welded timber construction requires a calculation tool for strength prediction to make those lumber pieces work practically. Initially probabilistic methods were used to determine the load bearing capacity. There the welded joints had both parallel and perpendicular natural fiber patterns. The mathematically calculated and experimentally determined strength were found to stay in good agreement with each other. Further research in this sphere will encourage investigations into more complex systems.

Now let us come back to the basics and take a tour of the history of welding science. As a preconceived belief, welding is possible using only a good conductor of thermal energy and electricity. The parent materials should be joined in such a manner that the physical and the chemical properties of the welded portion remain same as the matter itself. Not only the finished product should look like a single piece but must also retain the ditto chemical qualities. Therefore welding of wood, if judged in this light, does not seem to have any real life acquaintance. However, standing in 2016, this chapter in mechanical engineering has passed the test of time in the very ritualistic way of how welding is done. It is an almost unthinkable phenomenon! After all, Science never fails to surprise. At every instance, and that too in a very pleasant way.

  • ·        Reference:

The websites of EPFL & the University of Tennessee

Mechanical Knee Joint

Amputation involves the removal of the leg to a level above the diseased area. Amputation will only be advised once all other options to save the leg have been looked at.

Disarticulation of knee means amputation through knee joint. Various artificial knee joints are manufactured for pain relief, mobility, prevention of gross infection, and prevention of growth of a tumor. A joint is formed where two bones make contact. Mechanical knee joint helps relative motion and provide support to the human body. Mechanical knees are mainly of two types: single-axis and multi-axis. Single-axis knees comprise of hinge and they are considered to be the simplest, most economical and the most durable. The drawback is that they do not have stance control. That means amputees need to use their own power to keep themselves stable when standing. This type of knees have constant-friction control and a manual lock to prevent the leg from swinging forward rapidly. Multi-axis or four-bar knees are more popular because they have multiple axes of rotation, which allow stability, yet an easy-to-bend swing. Another advantage and popular option of polycentric knee or multi-axis knee is that the leg’s overall length shortens in stride, reducing the risk of stumbling. Polycentric knees are suitable for many amputees, including those who cannot walk securely with other knee and those who have knee disarticulation or bilateral leg amputations, or have long residual limbs. Several polycentric knees have fluid (pneumatic or hydraulic) swing control, which permit variable walking speeds.

Mechanical Knee Joint

Hydraulic control systems are considered to function very close to a normal knee. Hydraulic systems use liquid, usually silicone oil, to respond to a range of walking speeds. Although they provide a smoother gait, they are heavier, require more maintenance, and are more expensive, at least initially. Pneumatic control systems use pistons inside cylinders containing air. These cylinders are compressed as the knee is flexed. It stores the energy like a spring and then returns the energy to the knee as it is extended. A spring coil may be added for additional control. Pneumatic systems are considered to provide better swing control to friction knees, but to be less effective than hydraulic systems.

Ohio Willow Wood from Ohio, Össur from Iceland, Zimmer Biomet from Warsaw, Indiana, Stryker Corporation from Michigan, United States are among the few who have been manufacturing various types of knee joints. Össur Total Knee® 1900 and Total Knee 2000 are for low level activity and single speed walking, whereas Total Knee 2100 is for highly active lifestyle. Plus there is also GeoFlex™ Knee from Ohio Willow Wood. It  is specially designed for wearers who are just learning to walk or are less active.

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