what is indirect addressing mode?

The indirect modes are useful for array processing and other looping. With the 5/6 cycle "(indirect),y" mode, the 8-bit Y register is added to a 16-bit base address read from zero page which is located by a single byte following the opcode. The Y register is therefore an index-register in the sense that it is used to hold an actual index (as opposed to the X register in the 6800 where a base address was directly stored and to which an immediate offset could be added). Incrementing the index register to walk the array byte-wise takes only two additional cycles. With the less frequently used "(indirect,x)" mode the effective address for the operation is found at the zero page address formed by adding the second byte of the instruction to the contents of the X register. Using the indexed modes, the zero page effectively acts as a set of up to 128 additional (though very slow) address registers.

The 6502 is capable of performing addition and subtraction in binary or binary coded. Placing the CPU into BCD mode with the SED (set D flag) instruction results in decimal arithmetic, in which $99 + $01 would result in $00 and the carry (C) flag being set. In binary mode (CLD, clear D flag), the same operation would result in $9A and the carry flag being cleared. Other than Atari BASIC, BCD mode was seldom used in home computer applications.

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what is the format of floating point representation?

The data type

float

uses

IEEE 32-bit single

precision

format

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Try this coding HTML

<!DOCTYPE html>
<html>
<body>

<p><a href ="http://bcaraipur.blogspot.in"><button type =' button'>987</button></a></p>
</body>
</html>

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What is an Entity-Relationship diagram?

It is a graphical representation of tables with the relationship between them
ER diagram is a conceptual and abstract representation of data and entities. ER is a data modeling process, which is to produce a conceptual schema of a system, often an RDBMS and the needs in top down fashion. ER diagrams are derived by using this model.

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Mitigation of Noise pollution

Mitigation of Noise pollution

Reducing noise pollution by muffling the sounds at the source is one of the best methods in industry and for urban living.

Protective equipment is generally mandatory when noise levels exceed 85 dB(A) in industry.
Creation of green cover adjacent to municipal roads and in mines is the way to mitigate noise pollution.

It has been observed that noise level reduces by 10 decibels per every 10m wide green belt development.
Apart, redesigning industrial equipment, shock mounting assemblies and physical barriers in the workplace are also for reduction and exposure of unwanted industrial noise.

High way noise pollution can be mitigated by constructing noise barriers.

Artificial noise barriers are solid obstructions built between the highway and the residential areas along a highway.

They block major portion of noise produced by passing vehicles on a highway.

Effective noise barriers typically reduce noise levels by as much as half or more.

The construction of noise barrier maybe built in the form of earth mounds, vertical wall along the highways for creation of block age of sound generated by heavy vehicles.

Creation of greenbelt in the space between the residences and highways also reduces the noise nuisance.

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Prevention of soil erosion

Plants provide protective cover on the land and prevent soil erosion for the reasons:

(a) plants slow down water as it flows over the land (runoff) and this allows much of the rain to soak into the ground;

(b) plant roots hold the soil in position and prevent it from being washed away;

(c) plants break the impact of a raindrop before it hits the soil, thus reducing its ability to erode;

(d) plants in wetlands and on the banks of rivers are of particular importance as they slow down the flow of the water and their roots bind the soil, thus preventing erosion.

Preventing soil erosion requires technical changes to adopt.

Aspects of technical changes include:

(i) use of contour ploughing and wind breaks;

(ii) leaving unploughed grass strips between ploughed land;

(iii) making sure that there are always plants growing on the soil,and that the soil is rich in humus (decaying plant and animal remains). This organic matter is the "glue" that binds the soil particles together and plays an important part in preventing erosion;

(iv) avoiding overgrazing and the over-use of crop lands;

(v) allowing indigenous plants to grow along the river banks instead of ploughing and planting crops right up to the water's edge;

(vi) encouraging biological diversity by planting several different types of plants together;

(vii) conservation of wetlands.We can check soil erosion by adopting the following additional practices:

1. Intensive cropping and use of proper drainage canals.

2. Terracing on the sloping fields.This retards the speed of the flowing water.

3. Planting trees and sowing grasses.

4. Extensive aforestation practices to be carried out.

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Soil erosion and its prevention

Soil erosion by water, wind and tillage affects both agriculture and the natural environment.

Soilloss, and its associated impacts, isone of the most important (yet probably the least well-known) oftoday's environmental problems.

It is mostly due to poor land use practices, which include deforestation, overgrazing, unmanaged construction activity and road or trail building.

Soil is a complex mixture of living and non-living materials.

It provides anchorage and sustenance to plants.

Natural agents like water and wind, constantly tend to remove the top soil and cause erosion.

Rain falling upon the unprotected top soil, washes it down into the streams.

Due to the absence of plant covering, eroded soil cannot hold water.

Water rushes into the rivers and overflows as flood.

Dust storm also causes soilerosion.

The particles of top soil are picked up in such quantities that they form clouds of dust.

Human beings also cause soil erosion.

The growing human habitation and expansion of urban areas lead to removal of vegetation.

Once vegetation is removed, the naked soil gets exposed to wind and water.

Improper tillage is another causeof soil erosion.

Farmers often loosen the top soil for removing weeds and preparing seed beds.

They also leave agricultural fieldslying fallow for long time. These practices expose the top soil to the wind and cause erosion.

Soil erosion is always a result of mankind's unwise actions, such asovergrazing or unsuitable cultivation practices.

These leave the land unprotected and vulnerable. Accelerated soil erosion by water or wind may affect both agricultural areas and the natural environment, and is one of the most widespread of today's environmental problems. Soil erosion is just one form of soil degradation.

Other kinds of soil degradation include salinisation,nutrient loss, and compaction.

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