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Different values of the Hubble constant for extragalactic objects are not considered here. We give a number of examples of the extreme accordance of expansion rates of different fields of knowledge with the cosmological expansion rate. The coincidence of the expansion rates means that a common cause is almost inevitable. All these examples are gravitationally bound in themselves and in this case are subject to cosmological expansion. According to standard theory, this should not happen. We therefore question the common boundary of gravity and expansion for both theoretical and observational reasons and conclude that all gravitationally dominated objects participate in cosmological expansion or scale drift, contrary to general doctrine. The space expands with its contents while numerically maintaining distance, radius, rotation time and density. What is generally interpreted as an expansion is obviously a scale drift with a drift rate that corresponds to the size of the Hubble constant. The Earth is subject to expansion and scale drift. This results in numerically constant measured values. This drift apparently also applies to distant galaxies and other objects. The cosmological red shift is not interpreted here as a Doppler effect and numerical increase in distances, but in accordance with standard theory as an expansion or drift of the space-time scale. The expansion of the radii of galaxies makes the assumption of dark matter superfluous. The continents and our everyday environment are not subject to expansion or scale drift.

The study aims to reveal the transition features of agricultural land use in the Groundnut Basin of Senegal from 2009 to 2018, especially the impact of urbanization on agricultural land and the viewpoint of farmland spatiotemporal evolution. Integrated data of time series MCD12Q1 land-use images of 2009, 2012, 2015, and 2018 were used to provide a land transition in agricultural and urban areas through the synergistic methodology. Socio-economic data was also used to serve as a basis for the argument. The results highlight that: (1) Agricultural land increased by 14.53%, with a dynamic index of 1.45 from 2009–2018. (2) Over the same period, urbanization increased by 2.80%, with a dynamic index of 0.28. (3) In different regions, the transition of agricultural land in Kaffrine is most intense (expansion rate: 22.80%). The same situation of urbanization happened in Thiès Region with a value of 7.94%. Except for Thiès, agricultural land in other regions has not yet been subject to major pressure due to urbanization. Overall, the farming system in Groundnut Basin is an extensive model, the recommendations from the point of view of land-use planning and land law are necessary to ensure efficient agricultural land management in the area.

This paper studies the influence of assembly unit of expansive agents (CaO and calcium sulphoaluminate) on the limited and free compressive strengths, the limited expansion rate, carbonation resistance, chloride ion penetration resistance and corrosion resistance of reinforcement concrete. The dosages of expansive agent were 0%, 3%, 6%, 9%, and 12% by the total amount of cementitious materials. Two kinds of mineral admixture (blast furnace slag and fly ash) were applied in this study. Results show that suitable dosage (lower than or equal to 9%) of double expansion agent with a large amount of mineral admixtures can improve the limited and free compressive strengths. However, when the dosage of the double expansion agent is higher than 9%, the addition of the double expansion agent leads to the reduction of limited and free compressive strengths. The variation of the limit expansion rate reaches the maximum value when the curing age is 14 days. The increasing addition of expansive agents and lower water-binder ratio demonstrate positive effect on the limited expansion rate. Concrete with 60% mineral admixtures (fly ash and ground granulated blast furnace slag) shows lower limited expansion rate and higher compressive strength than the concrete with 50% mineral admixtures. Finally, the incorporation of double expansion agent can improve the resistance to carbonation, chloride ion penetration resistance, anti-corrosion of steel bars and mechanical strengths (the limited and free compressive strengths).

Exploring the coordinated development process of people–land allocation in the urbanization process of urban agglomerations is of great significance to promote improvement of the urbanization development level and quality and realize the healthy development of urbanization. We took nine urban agglomerations in China as the research object and the coupling between urban expansion and population growth as the entry point. The overall coupling and the spatial coupling were used to reveal the people–land coupling relationship of nine urban agglomerations at different time periods. We found that both construction land and population within each urban agglomeration were in the stage of continuous growth, and the increase of both was similar and synchronous. The overall and spatial coupling between urban expansion and population growth is increasing. The expansion rate of construction land is a factor that influences the overall and spatial coupling between urban expansion and population growth, i.e., the greater the expansion rate of construction land, the higher the overall and spatial coupling between urban expansion and population growth. This study provides a new perspective for exploring the coupling between urban expansion and population growth and offers a new approach for studying the relationship between the two.

In this study, the characteristics of the alkali-silica reaction (ASR) expansion of steel slag itself, mortar bars, and concrete specimens using steel slag as aggregate are individually investigated by the expansion test method, to determine if steel slag aggregate in concrete can provide volume stability. The results show that when steel slag is aged in water for one month, its self-expansibility is below the permitted limit of 1.5% according to the JIS A 5015 standard. The ASR test results show that the ASR expansion of the mortar bars continuously increased with the increase in the test period. However, all mortar bars were below the permitted limit of 0.1% after 14 days according to the ASTM C 1260 standard. In contrast, the ASR expansion of concrete specimens was above the criteria prescribed by the ASTM C 1293 standard. From the results, the expansion of concrete specimens could not be controlled within the permitted limit by the ASTM 1293 criteria, even if the expansivity of steel slag did not exceed the criteria. Meanwhile, considering the crack propagation patterns of the concrete specimens, the cracks due to ASR expansion developed and connected even when the expansion was below the permitted limit. Besides, when mineral admixtures were used as the binder in the concrete specimens, there were discrepancies in the results between the expansion rate and the crack properties, such as maximum length and total crack length. Therefore, to accurately determine the change in volume due to ASR expansion in concrete using steel slag as coarse aggregate, it is necessary to check the crack patterns in addition to evaluating the expansion rate.

As an effective indicator of urbanization, impervious surfaces play a significant role in urban planning and ecological protection. It is, therefore, important to characterize impervious surfaces in urban geographical studies. As a key city in East China, Xuzhou has experienced rapid urbanization in recent decades and is now becoming an environmentally friendly city. To better understand the spatiotemporal heterogeneity of Xuzhou&rsquo, s urban development, we extracted its impervious surfaces from Landsat images of 1995, 2003, 2010, and 2018 by a linear spectral mixture analysis. Then, a range of complementary methods including landscape indices, profile lines, median centers, standard deviational ellipses, and spatial autocorrelation were adopted to analyze the landscape pattern and expansion of impervious surfaces on both city and district scales. Results show that (1) there was a constant impervious surface expansion, originating in downtown Xuzhou, (2) promoting ecological protection in urban areas fragmented impervious surfaces with increasing heterogeneity and diversity overall, and (3) expansion directions and rates of impervious surfaces varied with district and town, and the central urban area expanded towards east and southeast, which could be related to their own resources and governmental policies. Findings from this study provide useful insights into urban planning of this economically prospective region.

According to the Fire Statistics Yearbook of the National Fire Agency of the Republic of Korea, the total number of fires in 2018 was 42,338, which resulted in 2500 victims and amounted to property damages of approximately 560 billion KRW. The number of fires in buildings where wood was used as a finishing material was 28,013 (66%) in that period. To minimize human and property damage, composite materials were prepared by mixing wood particles with expandable graphite. The physical and thermal properties of the composite materials were investigated. It was observed that the expansion rate increased by 341.7% according to the expandable graphite content. Additionally, the total heat released and the thermal conductivity decreased from 38.63 to 2.5 MJ/m2 and from 24.62 to 7.8 W/m&middot, K. The time to inactivity of white mouse in the smoke toxicity test was 14.9 min and exceeded the toxicity standard for flame retardant performance. The expandable graphite added to composite materials adopted worm-like shapes as a result of combustion, and it formed a fine lattice layer structure with 16&ndash, 22 &mu, m gaps that could reduce thermal conductivity. In addition, we can minimize the damage to people and property in the event of a fire.

Positive and negative effects on ecosystem services from plantation forestry in Europe have led to conflicts regarding non-native tree species. Sitka spruce (Picea sitchensis (Bong.) Carr.) is the most common plantation species in northwest Europe, covering 1.3 Mha. In costal Norway, Sitka spruce was intentionally introduced and is currently occupying about 50,000 ha. Sitka spruce was blacklisted in Norway in 2012, mainly based on the risk for invasive spreading, but little quantitative documentation exists on spread. Here we quantify spread from plantations into abandoned heathland and pastures in thirteen sites where natural regeneration occurs. Spread distances and zero-square distributions related to the nearest edge of the parent stand were fitted by use of Weibull. The median expansion rate was 0.8 m·year−1 in north Norway and 4.4 m·year−1 in west Norway. The maximum establishment distance measured was 996 m. A peak in sapling density occurred within 50 m from the edge, and there was a general decrease in saplings with increasing distance. Conversely, increase in zero-squares percentages occurred with increasing distance. We argue that inclusion of abundance in assessing spread is necessary to define invasiveness. Based on spread models and prevailing forestry practices we recommend that the establishment of new Sitka spruce plantations within 200 m of protected areas should be avoided.

The relationship between economic growth, expansion of urban land area and the broader issue of cultivated land conversion in China has been closely examined for the late 1980s and 1990s. Much less is known about recent urban expansion and if the effects of economic growth on this expansion have changed over time. This paper updates estimates of urban expansion for China and examines the relationship with city economic growth for 1993–2012. To see if patterns are robust to different types of evidence, administrative data on the area of 225 urban cores are compared to estimates of brightly lit areas from remotely sensed night lights. The trend annual expansion rate in lit area is 8% and was significantly faster in the decade to 2002 than in the most recent decade. Expansion is slower according to administrative data, at just 5% per annum, with no change in unconditional expansion rates between decades, while conditional expansion rates have declined. The elasticity of area with respect to city economic output is about 0.3. Over time, expansion of urban land area is becoming less responsive to the growth of the local non-agricultural population.

Quinoa (Chenopodium quinoa Willd.) has gained prominence worldwide over recent years and suddenly Peru has emerged as a major player in the global quinoa market. This study aims to analyze the expansion of quinoa farming in Peru in the period 1995–2014 and to discuss the changes in land-use the country has experienced as a result of the boom in the global demand for quinoa. Two statistical approaches, principal component analysis (PCA) and exponential smoothing, were applied in the data analysis to explore the evolution of the quinoa boom in Peru by periods and to forecast what the acreage expansion rate would have been if the boom had not occurred. The results show that the quinoa boom was responsible for an increase of 43% in the number of hectares planted with quinoa in 2014, in relation to the number predicted if there had been no boom. This provoked an acceleration of production in traditional quinoa farming areas and the extension of this activity to new regions. The consequences are already apparent in the land-use changes seen in Peru, namely the: (i) displacement; (ii) rebound; and (iii) cascade effects.

形態: カラー図版あり, Physical characteristics: Original contains color illustrations, Accepted: 2017-08-29, 資料番号: PA1810008000

Shape memory polymers can be programmed into a secondary geometry and recovered to their primary geometry with the application of a controlled stimulus. Porous shape memory polymer foam scaffolds that respond to body temperature show particular promise for embolic medical applications. A limitation for the minimally invasive delivery of these materials is an inherent lack of X-ray contrast. In this work, a triiodobenzene containing a monomer was incorporated into a shape memory polymer foam material system to chemically impart X-ray visibility and increase material toughness. Composition and process changes enabled further control over material density and thermomechanical properties. The proposed material system demonstrates a wide range of tailorable functional properties for the design of embolic medical devices, including X-ray visibility, expansion rate, and porosity. Enhanced visualization of these materials can improve the acute performance of medical devices used to treat vascular malformations, and the material porosity provides a healing scaffold for durable occlusion.

Urban expansion form is the most direct manifestation of urban expansion in space. Although it has been widely and vigorously studied, relatively little attention has been paid to reveal its spatiotemporal characteristics at the administrative level over a long timeframe. In this study, 31 Chinese municipalities and provincial capitals were selected as subjects to identify the urban expansion forms of provincial and higher level cities in China. First, urban expansion processes of these cities in the past four decades were reconstructed using remote sensing and geographical information system (GIS) technology. Then, the overall characteristics of urban expansion were presented to scientifically determine the urban expansion forms of the provincial and higher level cities in China. Afterwards, the annual expansion area per city (AEAC) index was employed to describe the urban expansion processes and determine the important time nodes of the 31 cities. Lastly, the urban expansion type (UET) index was adopted to analyze the spatiotemporal characteristics of urban expansion forms. Results indicate that (1) from the 1970s to 2013, urban lands in provincial and higher level cities in China expanded dramatically, with the central built-up area increasing by over 5 times, and urban expansion demonstrating an apparent spatial difference. The expansion rate of cities in East China was fastest with an AEAC of 13.78 km2, followed by that in Central China (AEAC = 9.67 km2). The urban expansion rate was slowest in West China (AEAC = 7.11 km2); (2) Affected by the national macro policies, urban expansion processes successively experienced four different stages: a slow expansion period (1970s–1987), an accelerating expansion period (1987–1995), a slowdown expansion period (1995–2000), and a high-speed fluctuating expansion period (after 2000); (3) The urban expansion forms of municipalities and provincial capitals were mainly edge-expansion supported by infilling expansion. The leapfrog form contributed minimally to urban expansion; (4) The edge-expansion form surged before 2010 and gradually slowed down after 2010. By contrast, infilling expansion kept increasing in the past four decades. Lastly, the rate of urban expansion via the leapfrog form fluctuated from the 1970s to 2013.