The D-11 from Caterpillar is among the series of tracked type tractors are among the largest conventional bulldozers in the world, second to the Komatsu D575. It comes in two variations, thestandard D-11R and the bigger and heavier D-11R CD.

The D-11 bulldozer is among the upper end of Caterpillars track type tractors, which range in power and size from the D-3 (77 HP) to the D-11R (935 HP).

The primary use for the D-11 is for moving large quantities of rock, dirt, etc. short distances in confined spaces. The D-11 is often times used in quarries. The price, size, power and weight of the D11 dictate that they are used primarily for major products. You can normally find the D11 used in forestry, mining, excavation, and quarry operations.

The D-11 is high known and favored for its amazing power and ability to rip into the earth, making them ideal for agricultural and rock ripping type work. The ripper is the long claw like device you can find on the back of the D-11. Rippers come in single shank or in groups of two or more, known as multi shank rippers. Normally, a single shankis all you need for heavy ripping work.

The ripping of rock will allow the ground surface rock to be broken up into small, easy to handle and transport rubble which can then be removed so that you can grade the area.

The agricultural ripping feature will allow rocky or very hard ground to be broken up so that otherwise unarable land can be put to use with
agricultural applications.

People who may be suffering from depression or manic disorders actually exhibit or show each and every kind of symptom of depression that doctors will tell you that depressed people have. Sometimes it’s actually quite easy to overlook such symptoms and not be able to help one’s self or others who are suffering from depression for that matter.

There are actually a lot of symptoms of depression that depressed people may actually posses but they don’t have to suffer from each and every one of them before you actually help them get diagnosed and be treated for this illness. Also, since symptoms of depression actually vary, the time of their "attacks" varies as well.

Here are some common examples of symptoms of depression:

Prolonged period of sadness or not feeling "up to it," people who are always feeling not in the mood, who’d rather mope around the house and feel sorry for one’s self is the best example for this symptom of depression.

Feels hopeless, perennial pessimist: speaking of feeling sorry for one’s self, another common symptom of depression is when a person actually feels like he/she has nothing to look forward to in his or her life. As for being the perennial pessimist, those who show this symptom of depression are usually very negative about things, again, the feeling of hopelessness comes in to mind.

Guilt-driven, loss of self-worth and helplessness: other symptoms of depression that can be easily seen on people who prefer to mope around all day long are these. Whenever a person feels so guilty over something, that actually makes one a very sad person who feels like he or she doesn’t deserve to be happy. Thus, the loss of self-worth, if that person feels like he or she isn’t worthy of being happy or enjoying one’s self then that’s clear tell-tale symptom of depression. Helplessness also contribute to being depressed, when assuming that things won’t simply go your way, it’s already a clear saying that you have absolutely no hope in your body at all.

Isn’t interested in finding or taking pleasure; just dropping the hobbies as well as the other things that one used to enjoy: this tell-tale symptom of depression just shows how depressed a person can be, if one is actually too sad to take pleasure even in the very things that one loves then that person is seriously lacking something, rather, that person might well have caught the depression bug.

Fatigue, always tired: people suffering from depression, since they’ve lost whatever interest in life that they may have had before are actually lacking of physical energy at all times, if one would prefer to just mope around, probably won’t even eat not get enough sleep, a depressed person may well be on their way to not just a mental illness but depression can actually be terrible for one’s physical health as well.

Having trouble concentrating, having bad memory and is indecisive: a person who is suffering from depression easily gives away this tell-tale symptom of depression. Wherein one’s lack of interest with regards to the outside world or for just about anything for that matter can lead to that person’s inability to lose track of things and actually not be able to remember things that happened or what other people said. Lack of interest actually makes depressed people very inattentive.

There are actually more symptoms of depression that can actually help you see if a person (or you) needs to be brought to the doctor to get some help when it comes to depression: lacking sleep, sleeping too much or waking up at wee hours of the morning are all symptoms of depression (if it happens on a daily basis), appetite loss as well as eating too much may show one’s lack of enthusiasm for life. Be weary of sudden weight loss or weight gain in those around you. Being suicidal, talking about death, about wanting to die is another clear indication that that person is depressed. Being restless and irritable and physical symptoms that are usually brought about by poor mental health such as headaches, digestive disorders and various body pains.