Firstly, the closest point of collapse is calculated approximately by utilizing the quadratic characteristic of power flow equations and the singularity of Jacobian matrix on the center point of high voltage solution and low voltage solution on rectangular coordination.

Then using the approximate solution as initial value of iteration, the nonlinear equations for the closest point of collapse are solved directly by Newton-Raphson method.

To avoid the singularity of Jaccobian matrix at Point of Collapse, zero eigen value method needs conversion to λ, which destroys the sparsity of Jaccobian matrix.

However, as the dimension of its equations is almost twice the ordinary power flow equations and it is not easy to make use of the advantages of sparse matrix technique, it is difficult to apply the point of collapse method to large systems.

The Sixth International Seminar of the Aga Khan Award for Architecture on "The Changing Rural Habitat" was held Oct. 19-21 in Beijing, and was attended by about 70 delegates from more than 20 countries. His Highness the Aga Khan personally presided over the meeting. On behalf of ASC, President Yang Tingbao first expressed hearty congratulations and warm welcome to His Highness the Aga Khan and all the celebrated delegates. He pointed out that it was a valuable academic activity. Speaking of the rural development...

The Sixth International Seminar of the Aga Khan Award for Architecture on "The Changing Rural Habitat" was held Oct. 19-21 in Beijing, and was attended by about 70 delegates from more than 20 countries. His Highness the Aga Khan personally presided over the meeting. On behalf of ASC, President Yang Tingbao first expressed hearty congratulations and warm welcome to His Highness the Aga Khan and all the celebrated delegates. He pointed out that it was a valuable academic activity. Speaking of the rural development in China, he reviewed the past experiences and the present-day need for rural reconstruction and housing, and the problems concerned. He believed that discussion with fellow architects and specialists of various countries would be very beneficial and significant and would give great help in subsequent work. Mr. Han Guang, Director of State Capital Construction Commission of PRC, spoke of the importance of rural habitat as a topic of great concern in the world today. He reviewed the rural development in New China, the encouraging perspective of rural economy, the increased pace of rural reconstruction, and the policy of "self-built with public aid" adopted in China. He looked at the seminar as a good opportunity to learn from experiences of other nations.Speaking of the seminar, his Highness the Aga Khan said: "This as an historic occasion. The people gathered here represent a unique concentration of intelligence and expertise in the topic that is to be delt with and on the questions that will be raised and must be answered. The place-the People's Republic of China-will provide the stimulus to encourage the innovation so desperately needed to solve the problems of rural peoples all over the world, but especially of the poor among them-and it will also supply the kind of perspective that only a country with millennia of history behind it can inspire. Finally, the ocassion coincides with-and is indeed a response to-the increasingly urgent demands on the part of rural peoples in the developing world not only for a longer, happier, and healthier life, but for achieving it without violating the regional differences, obliterating the traditional cultures, and destroying the natural environment that make life worth living." He explained that the word "habitat" refers not only to places where people live, but also the places where people ought to live.He further pointed out that the problem of the rural habitat is an almost overwhelming one for the developing countries of Asia and Africa. "The great cities of Asia and Africa are already almost at the point of collapse beneath the unrelenting pressures of immigration from the rural hinterlands. Somehow ways have to be found to make the countryside itself a more desirable place to live in, which in turn demands an ability to earn more and to save enough as individuals or families or communes to begin the process of self-generated economic growth and thus social wellbeing. The Aga Khan Award for Architecture seeks to identify and premiate all successful efforts in the resolution of man's built environment, and cearly the fate and future of the rural habitat must be of prime concern tous.......... Our central purpose here, then, is to increase understanding of the ruralhabitat and, from that understanding, to devise appropriate strategies for change, both for our colleagues in planning, architecture and other related fields, and for a wider audience of decision makers and concerned people everywhere."The following papers were read and discussed in the seminar:1. CHOLISTAN......................................................Kamil Khan Mumtaz2. THE PESANTREN: RURAL HOUSING AND DEVELOPMENT IN JAVA, INDONESIA.......................Hasan Uddin Khan, Farokh Afshar3. DEVELOPMENT OF RURAL HOUSING IN CHINA.........Zhao Bainian4. A SYSTEM OF SELF-HELP CONSTRUCTION ADOPTED IN RURAL SENEGALPart 1. .........................................................Brian Brace TaylorPart 2. ................................................................Kamal El Jack5. RATIONALIZED BUILDING SYSTEMS

Based on solving decomposedly equations of DC system and equations of AC system and considerating simply and directly the coupling relationship between the DC system and AC system. Point of collapse method is applied to voltage stability analysis of AC/DC power system,inital guess proposed can guarantee iteration to converge very fastly to the point of collapse needed,The proposed method is characterized by its simplicity of calculation,little amount of calculation and conenience of considerating restrain...

Based on solving decomposedly equations of DC system and equations of AC system and considerating simply and directly the coupling relationship between the DC system and AC system. Point of collapse method is applied to voltage stability analysis of AC/DC power system,inital guess proposed can guarantee iteration to converge very fastly to the point of collapse needed,The proposed method is characterized by its simplicity of calculation,little amount of calculation and conenience of considerating restrain of DC system variable and adjusting rationally operation mode,it can be applied to analyse the voltage stability of AC/DC power systems of any operation mode.

The high pressure split grouting is a foundation treatment method for general use. The rebuilding project of the 321 Natlonal Highway which is located in Bin County,Shanxi Province is being in construction. On the mountain body which is on the right point of collapse there is a towed sliding. The towed sliding is effectively consolidated by high pressure grouting method. The paper relates the details in the use of materials,construction and equipment etc.