scholarly journals A Study on the Barrier Zone Installation for the Streetscape and Pedestrian Environment Improvement

2019 ◽  
Vol 14 (1) ◽  
pp. 119-128
Author(s):  
Chae,Min-Kyu
Keyword(s):  
Barrier Zone

Западное пограничье СССР в 1939–1941 гг. как « буферная зона » (случай Западной Белоруссии)

2021 ◽  
pp. 1-22
Author(s):  
Yanina Karpenkina
Keyword(s):  
Buffer Zone ◽  
The West ◽  
Soviet Government ◽  
Soviet Policy ◽  
Barrier Zone

Abstract In 1939–1941, the Soviet policy in the new western borderlands was based on the need to transform quickly the annexed territories into a safe and invulnerable border. Thus, having expanded its territories to the west in 1939–1940, the Soviet government was in no hurry to eliminate the old border outposts. On the contrary, the previously existing Polish-Soviet border was preserved in the form of so-called “barrier zone” (« зона заграждения »), and special permits were still required to cross it. At the same time, the construction of new western borders was proceeding at an accelerated pace, and in parallel with this, a massive “purge” of the population of the new regions was carried out. Thus, in the pre-war years, the annexed territories were assigned the role of a kind of broad “buffer zone” that was supposed to protect the USSR from the west with two border lines—the new German-Soviet border (external) and the preserved former Polish-Soviet border (internal).

Simulation of Hydraulical Fracture Height by Creating Artificial Barrier

2013 ◽  
Vol 734-737 ◽  
pp. 1262-1267
Author(s):  
Chuan Min Li ◽  
Yong Quan Hu
Keyword(s):  
Stress Gradient ◽  
Fracture Propagation ◽  
Propagation Model ◽  
Open Crack ◽  
Fracture Criteria ◽  
Intensity Factors ◽  
Net Pressure ◽  
Fracture Height ◽  
Barrier Zone ◽  
Treatment Pressure

It is quite difficult for reservoir exploitation with worse barrier zone, especially in thin pay-zone, limiting hydraulic fracture height propagation. This paper described the theory of controlling the fracture height by creating artificial barrier, and net pressure distribution in the crack was determined by assuming the artificial barrier is with stress gradient. Then, stress intensity factors in the crack tip were gotten on the basis of fracture mechanics theory, and fracture propagation model was established in accordance with fracture criteria of tensile open crack. The established model also described the action of treatment pressure on the fracture height and influence of artificial barrier on the fracture height propagation. By contrasting the results, it is feasible for artificial barrier to limit the fracture height propagation, and this model also can be used in hydraulic fracturing design in the oilfield.

scholarly journals Spatiotemporal Dynamics and Driving Forces of Ecosystem Changes: A Case Study of the National Barrier Zone, China

2020 ◽  
Vol 12 (16) ◽  
pp. 6680
Author(s):  
Xiaofeng Wang ◽  
Yuehao Li ◽  
Bingyang Chu ◽  
Shirong Liu ◽  
Dan Yang ◽  
...  
Keyword(s):  
Driving Forces ◽  
Spatiotemporal Dynamics ◽  
Desert Ecosystem ◽  
Tibet Plateau ◽  
Ecosystem Change ◽  
Contribution Rate ◽  
Positive Role ◽  
Ecological Barrier ◽  
Ecosystem Changes ◽  
Barrier Zone

It is of great significance to study the spatiotemporal dynamics of the ecosystem and explore the driving forces that affect change in the ecosystem in the National Barrier Zone (NBZ). Based on multi-source remote sensing data, this paper analyzed the change in the ecosystem in the NBZ from 2000 to 2015. Natural and social economic factors were selected as the driving factors, and the change mechanism of the ecological system in the NBZ area was analyzed by means of redundancy analysis and other methods. The results showed the following: (1) Between 2000 and 2015, the ecosystem changes in the NBZ are obvious. It is important to note that the grassland and urban ecosystem increased by 13,952 and 6720 km2, respectively; at the same time, the desert ecosystem significantly decreased by 4544 km2. (2) The human activity represented by gross domestic product (GDP) is the main factor in the change of ecosystem change in the NBZ with a contribution of 75%, especially in the ecological barrier of the Sichuan–Yunnan–Loess plateau with a GDP contribution rate of 83%. (3) The changes in the ecosystems are significantly influenced by multifactorial interactions, such as the joint contribution rate of the drought index (PDSI) and GDP reaching 0.11 in the ecological barrier of Qinghai–Tibet plateau. (4) The ecological protection projects, such as the Green for Grain Project in the NBZ, play a positive role, and the ecological environment is improving. The conclusions of this paper will be used as a basic theory to contribute to subsequent research on ecosystem services, policy making, and other aspects in the NBZ.

scholarly journals Free Fatty Acids of the Skin Surface and Barrier Zone in Normal and Abnormal Keratinization

1963 ◽  
Vol 41 (5) ◽  
pp. 259-264 ◽  
Author(s):  
William M. Coon ◽  
Victor R. Wheatley ◽  
Franz Herrmann ◽  
Leona Mandol ◽  
Jean Gowdey
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Skin Surface ◽  
Barrier Zone

Photovoltaic action spectra of metal–phthalocyanine Schottky barrier cells

1983 ◽  
Vol 61 (10) ◽  
pp. 1416-1422 ◽  
Author(s):  
R. O. Loutfy ◽  
C. K. Hsiao ◽  
R. Ho
Keyword(s):  
Diffusion Length ◽  
Depletion Region ◽  
Generation Model ◽  
Carrier Generation ◽  
Action Spectra ◽  
Discharge Capacitance ◽  
Exciton Diffusion ◽  
Exciton Diffusion Length ◽  
Dc Discharge ◽  
Barrier Zone

We have measured the direct current (dc) action spectra of Al and In/phthalocyanine (α, β, and x-H2Pc and VOPc) photovoltaic cells in the wavelength range 400–900 nm. The data were analyzed in terms of both the local carrier generation and exciton diffusion models. According to the local carrier generation model, photoactive barrier widths w of 390, 475, 310, and 950 Å for In/α, β, x-H2Pc, and VOPc, respectively, were obtained. The depletion region width of In–phthalocyanine Schottky junctions were independently measured using a dc discharge capacitance technique. In all cases, the depletion region widths (capacitance) were consistently smaller than the photoactive collection region widths (action spectra). These results suggest that excitons produced within a diffusion length of the barrier can diffuse into the barrier zone and dissociate into collectable carriers. Using a combined local carrier generation and exciton diffusion model, a barrier width of the order of 200–300 Å and an exciton diffusion length of 300–500 Å was estimated for In/x-H2Pc cells.

scholarly journals Factors that Affect Spread of Pseudomonas syringae in the Phyllosphere

2003 ◽  
Vol 93 (9) ◽  
pp. 1082-1092 ◽  
Author(s):  
Christen D. Upper ◽  
Susan S. Hirano ◽  
Kimberly K. Dodd ◽  
Murray K. Clayton
Keyword(s):  
Pseudomonas Syringae ◽  
Field Experiments ◽  
Source Area ◽  
Brown Spot ◽  
Suitable Habitat ◽  
Measurable Effect ◽  
Bare Ground ◽  
Snap Bean ◽  
Source Areas ◽  
Barrier Zone

Successful spread of an organism to a new habitat requires both immigration to and growth on that habitat. Field experiments were conducted to determine the relative roles of dispersal (i.e., immigration) and bacterial multiplication in spread of Pseudomonas syringae pv. syringae in the phyllosphere. To study spread, individual plots consisted of three nested concentric squares with the inner 6 m2 planted to snap beans serving as the sink. Each sink, in turn, was surrounded by a barrier zone, usually 6 m wide, which was surrounded by a 6-m-wide source area. The source areas were planted with snap bean seeds inoculated with doubly marked strains derived from wild-type P. syringae pv. syringae B728a. The treatments were designed to test the effects of the nature and width of the barrier zone and suitability of the habitat in the sinks on spread of P. syringae pv. syringae. The marked strains introduced into the source areas at the time of planting were consistently detected in sink areas within a day or two after emergence of bean seedlings in the sources as assessed by leaf imprinting and dilution plating. The amounts of spread (population sizes of the marked strain in sinks) across barrier zones planted to snap bean (a suitable habitat for growth of P. syringae pv. syringae), soybean (not a favorable habitat for P. syringae pv. syringae), and bare ground were not significantly different. Thus, the nature of the barrier had no measurable effect on spread. Similarly, spread across bare-ground barriers 20 m wide was not significantly different from that across barriers 6 m wide, indicating that distance on this scale was not a major factor in determining the amount of spread. The suitability of the sink for colonization by P. syringae pv. syringae had a measurable effect on spread. Spread to sinks planted to clean seed was greater than that to sinks planted with bean seeds inoculated with a slurry of pulverized brown spot diseased bean leaves, sinks planted 3 weeks before sources, and sinks planted to a snap bean cultivar that does not support large numbers of P. syringae pv. syringae. Based of these results, we conclude that the small amount of dispersal that occurred on the scale studied was sufficient to support extensive spread, and suitability of the habitat for multiplication of P. syringae pv. syringae strongly influenced the amount of spread.

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