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지난 20세기가 전 세계적 인구 급증의 100년이라면 21세기는 인구고령화의 한 세기로 인구 고령화는 전 세계가 함께 경험하고 있는 현상이다. 아시아 국가보다 산업화의 경제발전을 조기에 달성한 선진국은 이미 인구고령화에 대응하고 있고, 현재 인구구조의 변화 속도는 안정적으로 움 직이고 있지만 한국과 중국, 일본의 경우에는 인구고령화 속도가 빠르게 진행되고 있다. 특히, 중국은 인구보너스의 유리한 측면을 이미 누리고 있으며, 특정 시기에 중국의 인구가 장기적으로 감소하기 시작할 것으로 예상되는 가 운데, 이 같은 장기적인 인구학적 현실은 중국의 미래 성장에 중대한 영향을 미칠 것으로 전망된다. 이에 본 연구는 1978년 개혁개방 이후부터 최 근 2021년까지, 44년 기간 중국의 거시경제 데이터를 이용하여 중국의 인구구조 변화가 중국경제 성장에 미치는 영향에 대해 분석하고, 분석결 과를 바탕으로 우리의 대응 방안에 대한 시사점을 도출하였다. 분석결과 향후 중국의 인구구조 변화에 따른 경제성장에 있어 전체 인구 중 청소년층 비율이 고령층 비율이나 부양 비율보다 큰 영향을 미칠 것으로 나타났다. 이는 청소년층 비중을 증가시키려면 현실적으로 출산율을 제고시키는 것이 실현 가능한 방안이 될 것으로 현재 중국의 추진하 고 있는 ‘세 자녀’ 정책에 더욱 힘을 실어야 하는 이유를 본 연구가 실증하였다고 볼 수 있다.

The 20th century was 100 years when the population soared worldwide, while the 21st century is a century of aging population, and now the world is experiencing aging population. Western developed countries, which have achieved industrialization and economic development earlier than Asian countries, responded well to the aging population, so the pace of change in the current population structure is moving stably, while Korea, China and Japan are experiencing rapid aging population. China already enjoys the advantage of the population bonus, but from a certain period of the future, China's population is expected to begin to decrease in the long run. This long-term demographic reality is expected to have a significant impact on China's future growth. This study analyzes the impact of China's demographic change on China's economic growth for 44 years using China's macroeconomic data from the reform and opening of China in 1978 to the recent 2021, and we have derived implications for our response to the situation based on the results of the analysis. The analysis showed that the proportion of youth among the total population will have a significant impact on the economic growth of China's demographic change in the future rather than the elderly ratio or supporting seniors ratio. Thus, in order to increase the proportion of youth, it will be a realistic way to improve the birth rate. This study has demonstrated the reason why China should seek more strongly ‘the policy for having three children’.

The Yeonsan Ogye (YO) chicken is a natural heritage of Korea, characterized by black feathers, skin, bones, eyes, and comb. The purebred of YO population has been reared under the natural mating system with no systematic selection and breeding plan. The purpose of this study was to identify the genetic diversity and find the optimal number of population sub-division using 12 polymorphic microsatellite (MS) markers to construct a pedigree-based breeding plan for the YO population. A total of 509 YO birds were used for this study. Genetic diversity and population structure analysis were conducted based on the MS marker genotype information. The overall average polymorphic information content value and expected heterozygosity of the population were 0.586, and 0.642, respectively. The K-mean cluster analysis based on the genetic distance result confirmed that the current YO population can be divided into three ancestry groups. Individuals in each group were evaluated based on their genetic distance to identify the potential candidates for a future breeding plan. This study concludes that a future breeding plan with known pedigree information of selected founder animals, which holds high genetic diversity, could be the best strategy to ensure the conservation of the Korean YO chicken population.

The study of genetic diversity was carried out in Atractylodes japonica KOIDZ.. Although this species has been regarded as medically improtant one, there is no report on population structure in Korea. Starch gel electrophoresis was used to investigate the allozyme variation and genetic structure of eight Korean populations of this species. Of the 15 genetic loci surveyed, nine (60.0%) was polymorphic in at least one population. GENETIC diversity was high at the species level (Hes=0.144), whereas, that of the population level was relatively low (Hep=0.128). Nearly 87% of the total genetic diversity in A. japonica was apportioned within populations. The sexual reproduction, high fecundity, and perennials are proposed as possible factors contributing to high genetic diversity. The indirect estimated of gene flow based on Gst was 1.69.

Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name "Cheongsong" is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K. pictus and K. pictusvariant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm = 0.857) indicated that gene flow was not extensive among Korean populations of K. pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K. pictus and K. pictus variant populations may have played roles in shaping the population structure of this species.

Genetic diversity analysis is crucial for maintaining and managing genetic resources. Several studies have examined the genetic diversity of Korean domestic chicken (KDC) populations using microsatellite markers, but it is difficult to capture the characteristics of the whole genome in this manner. Hence, this study analyzed the genetic diversity of several KDC populations using high-density single nucleotide polymorphism (SNP) genotype data. We examined 935 birds from 21 KDC populations, including indigenous and adapted Korean native chicken (KNC), Hyunin and Jeju KDC, and Hanhyup commercial KDC populations. A total of 212,420 SNPs of 21 KDC populations were used for calculating genetic distances and fixation index, and for ADMIXTURE analysis. As a result of the analysis, the indigenous KNC groups were genetically closer and more fixed than the other groups. Furthermore, Hyunin and Jeju KDC were similar to the indigenous KNC. In comparison, adapted KNC and Hanhyup KDC populations derived from the same original species were genetically close to each other, but had different genetic structures from the others. In conclusion, this study suggests that continuous evaluation and management are required to prevent a loss of genetic diversity in each group. Basic genetic information is provided that can be used to improve breeds quickly by utilizing the various characteristics of native chickens.

The objective of this study was to describe the population structure and inbreeding, and to quantify their effectson weights at different ages of Mehraban sheep in Iran. The analysis was based on the pedigree information of26990 animals and 10278 body weight records from birth to yearling age. Data and pedigree information werecollected during 1994 to 2011 by the breeding station of Mehraban sheep. The population structure was analyzedusing the CFC program. Inbreeding of all animals was calculated by INBUPGF90 program. All animals were groupedinto three classes according to their inbreeding coefficients: the first class included non-inbred animals (F=0); andthe second and third classes included inbred animals (0<F<0.05 and F≥0.05, respectively). The average inbreedingin Mehraban sheep was 1.69%. Founder equivalent (fe) values were estimated to be 4244, 3116 and 2965 during1994-1999, 2000-2005 and 2006-2011, respectively. The effective population sizes (Ne) were 363, 5080 and 5740during 1994-1999, 2000-2005 and 2006-2011, respectively. Generation interval was 2.15 years for this breed of sheep. Regression coefficients of birth weight, 3-month weight, 6-month weight and yearling weight on lamb inbreedingwere estimated to be -6.34?0.69, -14.68?5.33, 48.00?9.43 and 98.65?15.65, respectively. Both positive and negativeinbreeding effects were found in the current study. The utilization of a program for designed mating system, in thepresent flock, could be a suitable approach to keep the level of inbreeding under control.

Cyathea gigantea is a tree fern distributed throughout humid tropical regions of northeast India and other parts of the country. However, wild populations of this species are largely affected by various natural and anthropogenic activities. Therefore, an attempt was made to study the population structure and regeneration status of C. gigantea in and around greater Itanagar area of Papum Pare district, Arunachal Pradesh. Altogether 45 patches, ranging from 19.63 to 260 m2 of area, were randomly sampled to study population structure and regeneration status of the species. Population study showed highest number of youngs in the height class of 0.50-0.75 m while, immatures were recorded highest in the height class of 2.0 to 2.5 m. Majority of the matures belonged to 6-9 m height class while it was recorded maximum in the diameter class of 10-15 cm. Average density of C. gigantea was 0.07 individuals ha-1 which varied greatly among different patches with a range of 2 to 14. Significant correlations were found between patch size and density of youngs, immatures, matures and total density. Maximum concentration of youngs was observed in patch size 60-140 m2, while for immatures, it was highest in patch size 20-160 m2. Similarly, highest concentration of matures was observed in patch size 20-80 m2 and 80-180 m2. Population structure of the total population exhibited inverted pyramid shaped distribution. Population structure consisting of youngs, immatures, matures showed that around 60% patches lack of regenerating individuals which depict very poor natural regeneration of the species. Effective conservation strategies are therefore to be formulated to save C. gigantea from the threat of extinction in near future.

For the current decade and the next one, the age structure of the population shall be very favorible for our economy. The share of children in the total population will decrease while the older people share will remain almost unchanged. From viewpoint of the age structrure of the population, the population which is fewer, yet skillful, educated and healthy is better than the population with greater number but unqualified, uneducated and with poor health. To encourage the fertility increase, it’s more important to invest on improvement of the health state of the population and decreasing the mortality and poverty, than spending resources. In other words, focusing on the quality instead of the number of the population, Government shall make efforts to invest sufficiently to support the efficient employment of the workforce, taking into account the current and future tendency of the workforce group. Such policy could be the key for our country’s future development.

Sacred groves are large areas of virgin or human-modified landscape with a diverse range of species that have been protected by local people for centuries due to cultural, religious beliefs, and taboo that the deities live in them and protect the villagers from various calamities. The present study was carried out for quantitative analysis of diversity, population structure, regeneration and conservation status of tree species in the four 36.86 ha sacred groves of Jhargram district in West Bengal. Tree species composition, population structure and regeneration status were analyzed by randomly establishing of 1 ha subplots within the sacred groves. Density, frequency, basal area, abundance, evenness, and other diversity indices were calculated for adult trees with girth at breast height (GBH) ＞31 cm. A total of 146 tree species belonging to 116 genera distributed in 44 families from 21 orders were recorded. Pterospermum suberifolium, family Malvaceae showed the highest Species Importance Value Index (SIVI, 21.33) and Fabaceae showed the highest Family Importance Value Index (FIVI, 35.59) values respectively. Individuals are categorised into three groups, seedling, sapling and adult based on girth classes. The majority of tree species exhibited good (52.74%) regeneration followed by fairly (24.66%), poor (15.75%) and no regeneration (6.85%) respectively. With the healthy existence of the sacred grove, the overall population structure of tree species showed a strong regeneration potential. The current data will be useful in determining the current status of tree species and will be used by the forest department, politicians, and conservationists to establish management plans for the conservation of priority species in the region. Since the study areas were sacred groves, tribal members were keen to preserve them due to their religious significance.

In Ethiopia, dry land vegetation including the fairly intact lowland and western escarpment woodlands occupy the largest vegetation resource of the country. These forests play a central role in environmental regulation and socio-economic assets, yet they received less scientific attention than the moist forests. This study evaluated the woody plant species composition, population structure and carbon sequestration potential of the A. senegal woodland across three distance gradients from the settlements. A total of 45 sample quadrants were laid along a systematically established nine parallel transect lines to collect vegetation and soil data across distance gradients from settlement. Mature tree dry biomass with DBH＞2.5 cm was estimated using allometric equations. A total of 41 woody plant species that belong to 20 families were recorded and A. senegal was the dominant species with 56.4 IVI value. Woody plant species diversity, density and richness were significantly higher in the distant plots compared to the nearest plots to settlement (p＜0.05). The cumulative DBH class distribution of all individuals had showed an interrupted inverted J-shape population pattern. There were 19 species without seedlings, 15 species without saplings and 14 species without both seedlings and saplings. A significant above ground carbon (5.3 to 12.7 ton ha-1), root carbon (1.6 to 3.6 ton ha-1), soil organic carbon (35.6 to 44.5 ton ha-1), total carbon stock (42.5 to 60.7 ton ha-1) and total carbon dioxide equivalent (157.7 to 222.8 ton ha-1) was observed consistently with an increasing of distance from settlement (p＜0.05). Distance from settlement had significant and positive correlation with species diversity and carbon stock at 0.64** and 0.78**. Disturbance intensity may directly influence the variation of species composition, richness and density along the A. senegal woodland. The sustainability of the A. senegal woodland needs urgent protection, conservation and restoration.

At present the biodiversity of the riparian forest is under threat due to various anthropogenic pressures. Hence study was conducted along the three unprotected zones of riparian forest in Dikhu river, Nagaland, north-east India in order to compared the diversity, distribution and population structure of riparian trees. In each zone 100×100 m2 plot were marked and subdivided into 20 plots of 10×10 m2. 10 plots on each side of the river were taken randomly covering 0.02 ha. Only tree with dbh ≥10 cm and dbh above 1.5 m above ground level were recorded as individual species. A total of 29 tree species belonging to 18 families were recorded from the three zones of the river. Tree species richness was highest at the middle zone (19) followed by upper (14) and lower zone (7). The most abundant species and family recorded at upper, middle and lower zones were Melia azaderach of Euphorbiaceae (380 stems ha-1), Terminalia chebula of Euphorbiaceae (432.5 stems ha-1) and Duabanga grandiflora of Lythraceae (365 stems ha-1) respectively. The ranges of diversity indices observed in the three zones were: Shannon-Wiener index (1.25-0.73), Simpson diversity index (0.42-0.93), Evenness index (0.47-0.37) and Index of co-dominance (0.75-0.94). Rest of other indices were also estimated and compared. Distribution of trees shows the contagious pattern common in the upper and middle zones and regular in the lower zone. The girth size class analysis demonstrated that the riparian forest is in less mature succession stage. This study emphasize the need for management and conservation of riparian forest by developing policy to declare the riparian zone as protected area to prevent further degradation and loss of biodiversity from these unregulated zones along the river.

본 연구는 사회해체론의 관점에서 지역사회 인구구조와 지역 안정성의 관계 검증을 목적으로 하고 있다. 이를 위해, 본 연구에서는 우리나라 228개 기초자치단체를 대상으로 도시화⋅산업화로 인한 인구구조의 변화가 지역사회 범죄안전에 미치는 영향에 대하여 지역 경제여건과 도시화 수준, 지방 선거투표율을 통제하여 분석하였다. 분석 결과 첫째, 지역사회 내 인종의 다양성과 가족해체 현상은 지역사회 네트워크를 약화시켜 지역사회 안정성을 저해하는 것으로 나타났다. 둘째, 고령화는 지역 사회 안전성과 정적 관계가 있는 것으로 나타났으며, 셋째 지방선거투표율로 본 사회참여는 지역사 회 안정성에 긍정적인 영향을 미치는 것으로 나타났다. 이를 기반으로 본 연구에서는 인구구조의 변화에 대응하여 지역사회 문제를 스스로 해결할 수 있다는 지역주민들의 집합적 효능감 확대를 위해 다양한 측면에서의 공동체 및 공유 활동 지원정책의 필요성을 제시하였다.

This study examines the relationships between population structure and safety in local community in the view of social disorganization theory. Little is known about how demographic structural changes in local communities impact its social stability including crime safety. The findings show as follow. First, both family disorganization and ethnic diversification at the local community could increase social disorder by weakening social network among residents of local communities which is believed as the foundation of the collective control. Second, aging in the local community was found to be positively related to community safety since such demographic structure may increase social control in the local community. Lastly, political participation such as turnout in local election had a positive effect on community safety. This study suggests that collective efficacy can increase social stability in the local community facing demographic structural changes such as aging, ethnic diversification and family disorganization.

Non Timber Forest Products (NTFPs) has gained a lot of significance over the years as a means of income generation. Forests are playing a vital role in the supply of these products, however, due to their continuous extraction, the population of many species might have depleted. Very little information is known about community structure and population status of NTFPs. No specific studies have been made to find out the occurrence, availability of species and population status in the forests, supplying the resources. The present study has been carried out in community forests of the naturally occurring NTFPs in the temperate forest of the Ziro valley of Arunachal Pradesh. The main aim is to determine community structure, species composition and population status of NTFPs. Three forest stands viz., Nyilii, Dura and Gyachi were selected which are used by the Apatani tribe for extraction of the NTFPs. For evaluation of species composition and community characteristics, the sampling of the vegetation was done using the quadrat method. A total 137 species representing 68 families and 116 genera were recorded. Herbs represent the maximum diversity with 71 species followed by 35 shrub species and 31 tree species. The families Asteraceae and Rosaceaeae exhibited maximum representation followed by Urticaceae. The species under Fagaceae, Lauraceae, Rosaceae and Rutaceae were found to be important NTFP yielding species. Highest species richness was recorded in Nyilii having 124 species, while lowest in Dura with 102 species. Density of tree, shrub and herb ranged between 376 to 456 individuals ha-1, 2848 to 3696 individuals ha-1 and 31.44 to 36.64 individuals m-2, respectively. The total basal area was found to be highest (51.64 m2 ha-1) in Dura followed by Nyilii (25.32 m2 ha-1) and lowest in Gyachi (22.82 m2 ha-1). In all the three study stands the species diversity indices showed the trend, herbs ＞ shrubs ＞ trees while the evenness index showed the trend as shrubs ＞ herbs ＞ trees. The overall species similarity index was highest (82.35%) between Dura and Gyachi. About 80% of the total recorded species showed clumped distribution while, no regular distribution was shown by any species. The three selected stands harbor about 50 important NTFP yielding species which are being used commonly by the Apatani people in their day to day life. Among the three study sites, overall diversity of NTFP was found highest in the Nyilii stand while the density of population was found better in Dura and Gyachi stands. The population of many species was found to be low due to continue harvesting without any sustainable management by the communities. All the selected forest stands have the potentiality to grow the high value NTFP yielding species and if managed properly, they can support the livelihood and economy of the local communities.

독일의 통일에 따른 동서베를린의 통합은 도시지리학적 입장에서 살펴볼 때 분단기의 이질적 상황을 극복하고 통합된 도시체계를 정립시킬 수 있는 계기가 되었다. 그러나 도시의 통합과정에서 이질적 도시구조와 체계의 잔존으로 다양한 문제점이 초래된다. 본 고에서는 이러한 문제점 중 베를린의 인구변화, 도시경제 및 도시구조의 측면에서 살펴보는 가운데 베를린시의 도시계획에 나타난 특성과 해결방안을 분석하여 보고자 한다. 특히 1990년 동서독의 통일이 공포된 이후 동독지역을 중심으로 자본주의적 체제에 부합하는 체제전환(Transformation)이 급속히 진행되는 과정에서 사회적 및 도시공간적 양극화 현상이 발생하게 되었다. 이러한 양극화 현상은 베를린의 도시내부에서 뿐만이 아닌 베를린 연담지역으로 확산되는 현상을 빚게 되었다. 그 결과 도시사회적 및 공간구조적 통합에 부정적인 영향을 끼치게 되는바 베를린은 이러한 양극화 현상을 해소하고자 도시구조의 개편을 단행하기에 이른다. 이러한 관점에서 본 고에서는 통일 이후 베를린의 도시계획에 나타난 특성을 살펴보기 위하여 첫째, 베를린 도시계획의 배경이 되는 분단 전후 베를린의 상황을 간략히 조명한 뒤, 둘째, 통일 이후 지난 10년간 베를린의 체제전환과정에 나타난 인구변화, 도시구조적 및 도시경제적 변화를 서베를린의 상황과 동베를린의 상황을 대비하며 살펴보고자 한다. 이러한 동서베를린의 체제전환과정은 장차 남북한의 통일시 북한의 도시가 직면하게 될 시사점을 띄고 있다. 따라서 결론에서는 독일의 사례를 기초로 북한이 통일에 따른 체제전환의 과정을 거칠 경우 사회적 및 공간적 안정과 지속적 발전을 위한 방안을 도시계획적 입장에서 제시하게 될 것이다.

Background: PM_2.5 pollution has been a persistent problem in South Korea, with concentrations consistently exceeding World Health Organization (WHO) guidelines. The aging of the population in the country further exacerbates the health impacts of PM_2.5 since older adults are more susceptible to the adverse effects of air pollution. Objectives: This study aims to evaluate how the health impact (premature death) due to long-term exposure to PM_2.5 in South Korea could change in the future according to the trend of change in the country's population structure. Methods: The study employs a relative risk function, which accounts for age-specific relative risks, to assess the changes in premature deaths by age and region at the average annual PM_2.5 concentration for 2022 and at PM_2.5 concentration improvement levels. Premature deaths were estimated using the Global Exposure Mortality Model (GEMM). Results: The findings indicate that the increase in premature deaths resulting from the projected population structure changes up to 2050 would significantly outweigh the health benefits (reduction in premature deaths) compared to 2012. This is primarily attributed to the rising number of premature deaths among the elderly due to population aging. Furthermore, the study suggests that the effectiveness of the current domestic PM_2.5 standard would be halved by 2050 due to the increasing impact of population aging on PM_2.5-related mortality. Conclusions: The study highlights the importance of considering trends in population structure when evaluating the health benefits of air pollution reduction measures. By comparing and evaluating the health benefits in reflection of changes in population structure to the predicted PM_2.5 concentration improvements at the provincial level, a more comprehensive assessment of regional air quality management strategies can be achieved.

인구와 재정지출에 관한 선행연구는 인구구조를 세분화하지 못하고 특정한 국가의 경우에 한정해서 분석했다는 한계성이 있다. 이에 대해 본 연구는 국가간 통계자료를 이용하여 청소년층․근로 인구층․노년층으로 인구를 세분화한 후, 이러한 변수가 재정지출의 규모 및 구조에 미치는 영향을 추정하였다. 특히 인구구조의 노령화가 건강이나 사회보장비와 같은 재분배적 재정지출의 증가를 가져온다는 기존 가설의 타당성을 실증적으로 검토하였다. 실증분석 결과에 의하면, 노년층 인구비율이 높은 국가일수록 평균적으로 높은 수준의 재정지출과 재분배적 재정지출의 비율이 증가하는 것으로 나타났다. 반대로 청소년층 인구비율이 높은 국가는 평균적으로 낮은 수준의 재정지출과 전통적 공공재인 국방비와 준공공재적 재정지출인 교육비가 차지하는 비중이 높은 것으로 추정되었다. 이러한 결과는 노년층 인구가 증가할수록 재정지출 구조에서 사회보장비가 차지하는 비율이 증가함을 의미하는데, 이는 장래의 경제성과에도 영향을 미칠 뿐만 아니라 과도한 재정지출의 팽창에 따른 복지재정 개혁의 필요성이 제기될 수 있다는 시사점을 제공한다. 또한 재정지출의 구성 비율을 결정함에 있어 정치적 과정을 통한 세대간 경쟁이 생겨날 수 있다는 사실을 암시한다.

The existing literature paid little attention to the analysis on the linkage between age structure of a population and government spending. In this paper, an empirical examination is made of the impact of age structure of population, in terms of young age (below 15), working age (15-65) and old age (above 65), on the composition of government spending as well as its total amount. In particular, it is considered whether rising longevity affects the redistributive expenditures, such as health and social security. Using a cross-section of countries, it is found that a country with a higher ratio of old age to total population is positively and significantly associated with redistributive expenditures as well as total amount of government spending. On the contrary, a country with a higher ratio of young age to total population results in a lower level of government spending and higher levels of both national defense a traditional public good and education a quasi-public good. These results imply that an increase in longevity requires more redistributive expenditures, which has some implications on the aggregate economic performances and the refinement of finance on a welfare sector. In addition, it does suggest the competition between generations on the determination of the composition of government spending in the political process.

본 연구는 2007년 이후 한국의 인구구조 변화가 수혜-부담 체계에 미친 영향을분석하였다. 본 연구는 한국의 수혜-부담 체계를 간단한 순조세함수로 나타내고, 가구주 연령구조의 변화를 통제할 경우 이 순조세함수의 누진도가 어떻게 변화하는지 재정패널 자료를 이용하여 추정하였다. 추정 결과 2007년부터 2019년까지순조세함수의 누진도 총 증가분의 약 30%는 가구주 연령구조의 변화에 기인한것으로 나타났다. 이렇게 가구주 연령구조의 변화가 순조세함수의 누진도를 증가시키는 효과는 주로 복지수혜의 누진도 증가를 통해 나타나는 것으로 확인되었다. 또한 동 기간 중 가구주 연령구조의 변화는 수혜-부담 체계의 소득재분배 효과 증가분의 약 40%를 설명하였다.

This paper examines the effect of population ageing on Korean tax-benefit structure. This paper estimates a simple net tax function using National Survey of Tax and Benefit (NaSTaB), controlling for changes in the household head’s age structure. We find that the progressivity of the net tax function more than doubled between 2007 and 2019, while about 30% of the change accounted for by population ageing. The effect of population ageing on the progressivity is mainly through government transfers. We also find that population ageing explains about 40% of the rise in the estimated income redistribution effect of Korean tax-benefit structure.

Agaricus bisporus is an important edible mushroom that is used as a functional food. In this study, European A. bisporus strains were analyzed for genetic diversity, population structure, and genetic differentiation using simple sequence repeat (SSR) markers. European A. bisporus strains were divided into four groups by distance-based analysis and two subpopulations by model-based analysis. The SSR markers used in this study did not group European A. bisporus strains by geographical region or pileus color. Genetic diversity was high in Group 4 based on distance-based analysis and Pop. 2 based on model-based analysis. A. bisporus strains showed very low genetic differentiation. The results of this study can be used for breeding A. bisporus in the future.

Purpose: This study standardizes the position and direction of devices based on general user expectations and stereotypes. Population stereotypes are cognitive structures that contain the perceiver's knowledge, beliefs, and expectations about human groups. In this paper, the stereotypes that people typically expect when manipulating 'cylindrical key-in-knob locks' and 'lever-type water faucet handles' were investigated and data regarding their expectations were collected. Methods: Two sets of 600 participants, between 13 and over 60 years old, were recruited for the experiment. Each group was evenly subdivided into six age groups. Each participant was presented with cylindrical door locks mounted on a miniature door and actual lever-type water faucet handles mounted on a mockup sink. Results: If the cylindrical lock was positioned 'vertically,' 59.2% of the participants expected the device to be locked, and if the lever type faucet handle was positioned 'up,' 63.0% of the participants expected the device to be turned on. Thus, daily-use devices should be designed consistent with user expectations of operation. There was a significant difference between genders for manipulating the faucet handle between up and down. Conclusion: A more general stereotype may be defined by repetitive measurements under the same test conditions with fixed time intervals, as well as accounting for people with cognitive problems.

21세기 들어서 인구대국 중국은 선진국이 아님에도 빠른 인구 고령화를 겪고 있다. 출산 율이 급감한 반면 경제성장으로 기대수명이 증가하여 2000년 ‘고령화사회’에 진입하였고, 2021년에는 ‘고령사회’에 진입하였으며, 2030년에 ‘초고령사회에 진입할 것으로 예상된다. 이는 인구 고령화 속도가 가장 빠른 나라였던 일본보다도 빠른 속도이다. 급격한 인구의 고령화는 경제성장 잠재력을 둔화시키기도 하지만, 한편으로는 실버시장이라는 새로운 기 회를 제공한다. 중국의 실버산업 규모는 2030년 20조 위안, 2050년 100조 위안 규모로 크게 늘어날 것으로 전망된다. 이에 중국의 급속한 인구 고령화 현상을 파악하고, 중국 실버시장 의 독특한 특징인 '신세대노인'을 이해하는 것이 중국시장 공략에 대단히 중요한 과제가 될 것이다.

In the 21st century, China, a large population, is experiencing a rapid population aging even though it is not an advanced country. While the fertility rate declined sharply, life expectancy increased due to economic growth, and entered an 'aging society' in 2000, entered an 'aging society' in 2021, and is expected to enter an 'super-aged society' in 2030. This is faster than Japan, which had the fastest population aging rate. The rapid aging of the population also slows economic growth potential, but on the other hand, it provides a new opportunity: the silver market. China's silver industry is expected to increase significantly to 20 trillion yuan in 2030 and 100 trillion yuan in 2050. Therefore, understanding the rapid aging of China's population and understanding the unique characteristics of the Chinese silver market, the ‘new generation of elderly', will be a very important task in targeting the Chinese market.