Gas car The social profit generated by enterprise activities is the addition of economic profit or the external economic effect of the activity. Companies may make significant monetary profits, but external economic effects often result in negative results, and substantial social profits may be minimal. Such as the industrial revolution, the mass production of the factory is low cost and price of product, but in order to earn maximum profit, factory owners and lower production costs, lead to the low wages of child labor, as well as improper handling industrial waste or contaminants and other social burden. To do this, monetary and fiscal policymakers must work together, including letting the central bank liquidate its budget deficit in extreme circumstances. But central bank independence is an obstacle, not a help, in working with the financial sector. The conversion of commodity value into cost price + profit (k+p) includes the possibility of deviation from the residual value. Because profits for more than the balance of cost price, and the cost price is less than the goods value, it provides the individual capitalists in cost price above and below the value of the possibility of selling goods, so that to achieve the profit with the goods actually contains surplus value does not agree in number. The capitalist makes use of the difference between the value of the commodity and the cost price, as a driving force in the market competition. As the competition between different production department and the free flow of capital, make different special margin balance into average profit margins or average profit margins, so that the profits further into average profit, realize the amount of capital to achieve the same amount of profit. In the usual case, the average profit and the surplus value are inconsistent in quantity. The average profit is proportionately proportional to the total amount of capital in advance and not the amount of live labor that is governed by individual capital. This and make an objective truth, essentially profits is the product of capital, it is nothing to do with labor, in this way, capital on the relationship between the wage labor to make money and to be make, will be further. At the same time, because of the surplus value for money is the commodity that only appeared well after the completion of the production process, it is further considered capitalists in order to produce goods all prepaid capital input by the capital employed are not included in the cost price (including those fixed capital). Not only that, the flow of goods from the production process into the process, in order to engage in sales activities to additional capital (including pure circulation costs), therefore, the residual value is considered to be not only all capital in advance in the field of production, but also be regarded as include all of the advance in the field of production and circulation of capital brought together. Network planning technology is a scientific method of planning and management, which is developed with the development of modern science and technology and industrial production. In the 1950s, in order to meet the needs of scientific research and the management of new production organizations, some new methods of planning management were introduced abroad. In 1956, dupont studied the key line method of network planning technology (CPM) and tried it on a chemical engineering project, and achieved good economic results. In 1958 the United States naval weapons when "Polaris" missile plans, applied the plan evaluation method (abbreviated as PERT) project plan arrangement, evaluation, audit and control, was a huge success. In the early 1960 s, the network planning technique, has been in the United States all new construction fully adopt this kind of new method for program management, could be introduced into Japan and Western Europe and other countries. With the rapid development of modern science and technology and the continuous improvement of management level, network planning technology is also developing and improving. At present, it has been widely applied in the fields of industry, defense, construction, transportation and scientific research of the world, and has become a scientific method of modern production management in developed countries.