This paper uses the short-form, long-form, and long-form 1% sampling data from the seventh national population census to analyze the living style of the elderly aged 65 and above. According to the data in the short form, among households with two elderly people, the percentage of elderly couples living alone is more than 55%, while among households with one elderly person, more than 36% of the elderly live alone. The data in the long form show that the vast majority of the elderly live at home, and less than 1% live in institutions. According to the long-form 1% sampling data, the total proportion of elderly couples living alone and singles living alone exceeds 50%. China's contemporary elderly people has entered an era dominated by couples living alone and single living alone.

Population ageing, as a common phenomenon in developed countries, has now become a challenge for many developing countries in the “post-demographic dividend era”. Although population ageing causes supply-side shocks such as labor shortages, its impact also includes positive aspects. By using UN population data and industrial robot data, this study examines how population ageing affects the application of industrial robots. The results indicate a significant increase in the utilization of industrial robot due to population ageing. This effect is realized through three channels: the labor cost anti-driving effect, the human-machine conflict weakening effect, and the human capital accumulation effect. Furthermore, the results of heterogeneity analysis show that the driving force is more pronounced in countries (regions) with higher strategic readiness, technical readiness, and talent readiness in the field of intelligent manufacturing. Therefore, it is crucial to strengthen strategic deployment, technological research, and talent training in the field of intelligent manufacturing to unblock the channels for releasing the positive impact of population ageing.

Data from the four population censuses since 1982 reveals the state and changes of China's urban household structure in different institutional environments. In the early stage of the reform and opening up when the planned economy system was dominant, household nuclearization tended to be prominent according to the 1982 and 1990 census data. Relaxation of the migration policy led to reduction of single-parent households, and the birth control policy promoted growth of couples households. Under the socialist market economy system after 1992, the types of household registration of urban population became diversified，and the welfare housing system began to transform into commercialized housing system. Based on the 2000 census, nuclear household continue to be of a high proportion，but the tendency of household nuclearization is restrained. After 2000, the birth control policy, elderly social security and housing reform have had profound impacts on urban household structure.

Newborns are the key of maternal and child health care, national health management, and population statistics. It is of great significance for national population management and comprehensive social governance to promote the construction of basic information database of newborns. It has also been listed as one of the key contents of the National Population Development Plan (2016-2030).With the gradual improvement of management and informatization of birth medical certificates in China, the birth medical certificate system has become an increasingly important source for timely and accurate access to the basic information of newborns. Through comparing the differences of birth population statistics and methods from various departments and reviewing the history and policies of birth registration and birth medical certificates management, this paper analyzes the current situations of birth population statistics and existing problems during the informatization process. We then put forward some suggestions to improve the quality of birth population statistics in China based on the birth medical certificate information system.

 Data from the four censuses since 1982 show that there are both similarities and differ- ences in the household structure between urban and rural married people at different stages of their life course. In urban areas，the majority of newly married people had established independent living u- nits. After giving birth to the first child，women mainly lived in nuclear households. When children grew up and became married，the proportion of the " empty nest" household among the elderly couples in- creased considerably. A gradually growing trend was observed in the widowed elderly living alone. However，widowed elderly living with their married children still accounted for a larger propor- tion. Before 2000，the household structure of rural married people was similar to that of their urban counterparts over their life course. In 2010，the proportion of newly married people living alone was low- er than that in 2000. The proportion of nuclear households declined for those married people who just had the first child，while the proportion of young married people living with parents or parents in law in the lineal household increased.

Intergenerationalfunctional relationship is an institutional system including obligation，responsibility，right to inheritance，mutual exchange and emotional communication．In the era of the contemporary social transformation，parents spend more money on their children’s education than in the past．Instead，adult children spend less cost to support their elderly parents than in the past．The obligation for adult children to take care of their parents is relatively reduced，but the elderly parents who could not take care of themselves have to mainly depend on their adult children．With the only child growing up，the daughter’s role is increasing in the intergenerational functional relationship，and even has no alternative．On the other hand，as the prolongation of life expectancy and increase of generations of lineal members，this will likely increase the burden of the adult children caring for elderly．Overall，at present，adult children's feedback function has declined and will directly affect the reproductive behavior of couples at childbearing age．The reasons for the weakening intergenerational functional relationship are as follows: social welfare system has played a role as an alternative to son in supporting the elderly，some objective factors have limited the play of family function，subjective consciousness of keeping intergenerational relationships has been weakened，the new institution environment that maintains intergenerational relationships has not been established．

Housing for migrant workers has become a major social challenge to the large-scale urbanization in China. Many studies have demonstrated housing disadvantages of temporary migrants in thatmigrants have limited access to both market-based housing due to their economic conditions and government-
sponsored affordable housing due to their official residency (hukou). In particular，much literature has analyzed institutional and individual factors of migrant housing conditions. This paper，however，investigates the extent to which migrant workers are able to move from employer-provided dorms or housing provided by social ties to market-based housing while working and living in cities，and institutional and individual factors contributing to such changes. Statistical analysis using data derived from a twelve-city migrant survey shows that，whereas most migrant workers live in dorms from employers and housing from social ties upon moving to cities，many of them gradually move to rent or even purchasing housing from formal and informal housing markets. The odds of such change are significantly influenced by factors such as years of working in the city，types of migration，willingness to permanently settle in the city，migrant social capital，education and types of Danwei .  

In contemporary China，lineal families with three generations have been a typical family formation since the early 1980s. However，this trend differs between urban and rural areas. When children growing up in urban one-child families，especially after their marriage and childbearing，most of
them would not change their preference for a small family. In rural areas，the number of families with only one son has increased since the early 1980s. When growing up，most of those sons work outside the villages. Once getting married and bearing child，they need help from their parents for housework
and childcare. Since such family arrangement is beneficial to young people，its proportion has increased. The majority of the householders of lineal families with three generations were in the middle and early old age in 2010 and their family function of supporting elderly has been weakened. More than half of the lineal families with three generations have no members aged 65 and above in 2010. At the same time，the infant proportion of the lineal families with three generations has gradually increased since the early 1980s. The function of taking care of children has been enhanced in this kind of family.

Drawing upon data from a twelve-city migrant survey conducted in 2009， this paper takes the advantage of structural equation modeling to examine the determinants of settlement intention of migrant workers， and to explore the mechanism of how these determinants indirectly affect settlement intentions via
city attachment． Model results show that the sense of city attachment plays an important role in determining rural migrantsintention to make permanent settlement in cities． Migrants of more years of education，being single， having skilled job， and with spouse or boy or girl friend in the same city are more willing to settle in cities． Having access to formal housing， frequently interacting with local people， and mastering local language not only positively affect the intention to settle in cities， but also indirectly and positively affect settlement intention via city attachment． The direct negative effect of size of social network on settlement intention is greater than the indirect positive effect via city attachment． Experience of discrimination and gender role also indirectly affect settlement intention． Model results also demonstrate the significance of further distinguishing the direct and indirect effects．

The major objective of population policy for the main functional region division is to achieve the appropriate distribution of population and orderly population flow.Coordinated economy-population distribution is the most important "rationale" based on the interpretation of this objective.Results from models measuring the coordination of regional economy and population show that the "rationale" is common in developed countries and the economy-population distribution in China is irrational.Analyzing with the circulatory accumulation theory of Myrdal,it is concluded that the institutional determinant for the irrational population distribution in China is the "cutting corners" development mode without being "people centered",resulting in inefficiency of the interconverting channel of economic benefit and population welfare,and there are institutional barriers between economic development and population agglomeration.Institutional adjustment policies on finance and tax system,population management system and evaluation system of political achievement are discussed in the paper.

Under the private land ownership before the land reform,nuclear family,while it was the biggest family type,wasn’t the overwhelming majority.Although taking the second place,lineal family type accommodates the greatest percentage of population.Composite family ranked the third,and about a quarter of village population lived in this family type.Impact of the collective economic system on family structure was that the family head was deprived of their control power over land and other basic production means,thus they lost their ability to restrain son’s demand for family division.Composite Family gradually decreased and finally disappeared.Nuclealization of family was achieved in the late 60s and early 70s of the 20th century.Labors of the investigated village began to engage in non-farming activities,but most of them didn’t leave families,and transition to non-agricultural employment of villagers has not had a major impact on family structure.At present,arrangement of meal and residence rotation of the elderly parents with two or more sons is universal in the village.Parents who are in meal and residence rotation periodically attach themselves to a married son’s family and form a intermittent lineal family,and at the same time rotary lineal families are formed.This type of families is specifically designated,reflecting special features of lineal family.