Wyniki wyszukiwania - Biblioteka Nauki

1

On a system of rational difference equations ...[wzór]

100%

Liu K. , Li P. , Zhong W.

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tom Nr 51

105--114

EN

In this paper, we are concerned with a three- dimensional system of rational difference equations. We present solutions of the system in an explicit way and obtain the asymptotical behavior of solutions according to initial values. We also give sufficient conditions of existing four-period solutions.

2

A Novel Through Capacity Model for One-way Channel Based on Characteristics of the Vessel Traffic Flow

100%

Nie Y. , Liu K. , Xin X. , Yu Q.

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tom Vol. 11, no. 3

495--502

EN

Vessel traffic flow is a key parameter for channel-through capacity and is of great significance to vessel traffic management, channel and port design and navigational risk evaluation. Based on the study of parameters of characteristics of vessel traffic flow related to channel-through capacity, this paper puts forward a brand-new mathematical model for one-way channel-through capacity in which parameters of channel length, vessel arrival rate and velocity difference in different vessels are involved and a theoretical calculating mechanism for the channel-through capacity is provided. In order to verify availability and reliability of the model, extensive simulation studies have been carried out and based on the historical AIS data, an analytical case study on the Xiazhimen Channel validating the proposed model is presented. Both simulation studies and the case study show that the proposed model is valid and all relative parameters can be readjusted and optimized to further improve the channel-through capacity. Thus, all studies demonstrate that the model is valuable for channel design and vessel management.

3

Permeability of P and K-nutrient through polystyrene membrane from aqueous solutions of urea + KH2PO4

88%

Deng X. , Liu K. , Han X. , Hu X. , Zheng S.

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2018

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tom Vol. 20, nr 4

113--122

EN

With the polymer-coated fertilizer as background, the permeability of P- and K-nutrient through a representative polymer membrane-polystyrene membrane were investigated by measuring their permeability in the solutions of KH2 PO4 -water and urea-KH2 PO4 water at nominal temperature of 298 K using the Ussing chamber method. To analyze and interpret the variation of permeability with solute concentration, the solubility of permeate in polymer membrane were determined experimentally and the permeate diffusion coefficient were assessed by the measurements of density and apparent molar volume of the aqueous fertilizer solutions. An interesting “increase-decrease” trend for the permeability of both phosphorous (P)-nutrient, and potassium (K)-nutrient fertilizer with permeate concentration was observed, in which the increases in permeability at low concentrations of permeate could be attributed to the increase in solubility of KH2 PO4 in polymer while the decreases in permeability at high concentrations was due to the decrease in diffusion coefficient of permeate in polymer membrane. Finally, the release kinetics of these nutrients from a PS-coated urea-KH2 PO4 compound fertilizer granule was predicted using the Shaviv’s model along with the permeability data of P- and K-nutrient generated.

4

Udoskonalenia wprowadzane do zabezpieczenia różnicowego transformatorów - doświadczenie płynące z projektowania testów

88%

Yip H. T. , Moscoso M. , Lloyd G. , Liu K. , Wang Z.

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tom R. 80, nr 5

62-66

PL

Przedstawiono nowe algorytmy działania zabezpieczenia różnicowego transformatorów wykorzystujące prądy stabilizacji stanu nieustalonego.

EN

The paper presents new algorithms of operation of differential protection of transformers taking advantage of stabilizing currents in transient state.

5

Assessing nutrient elements as indicators for soil active organic carbon in topsoil of karst areas

75%

Qiu H. , Liu J. , Li L. , Liu K. , He X. , Su Y.

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nr 3

EN

In karst areas, in order to ascertain the relationship between soil active organic carbon fractions and soil nutrient elements, topsoil samples (the sampling points were set at 80-m intervals) were collected for the analysis of soil physicochemical properties. In the sampling area, land use was divided into upland, paddy, and shrub land. The results showed that dissolved organic C (DOC) and microbial biomass C (MBC) contents in shrub land soil were higher than those values in upland and paddy soils (p<0.05). The total nitrogen (TN) content in paddy was lower than in upland and shrub land (p<0.05). The mean value of total phosphorus (TP) in upland and shrub land was approximately 1.5 times higher than that in paddy. Available nitrogen (AN) in shrub land soil was higher than in upland, whereas Olsen-P was lowest in shrub land in all soils (p<0.05). The C:P and N:P ratios in upland and paddy were lower than in shrub land (p<0.05). At plot scale, random forest analysis revealed that pH and soil organic carbon (SOC) were the most important variables determining DOC content in croplands (upland and paddy) and shrub land, respectively. The accumulation of SOC accelerates the growth of microbial biomass in upland. In shrub land, increases in SOC and total nitrogen were in favor of microbial growth. At the small-watershed scale, C:P and N:P ratios had a significant and positive effect on the content of DOC and MBC, respectively. The results implied that high C and N availability, especially in combination with low P availability, is helpful for increasing soil microbial biomass.

6

Collaborative 3D-To-2D Tight-Fitting Garment Pattern Design Process for Scoliotic People

75%

Hong Y. , Zeng X. , Bruniaux P. , Liu K. , Chen Y. , Zhang X.

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tom Vol. 25, no. 5 (125)

113--118

EN

This paper presents a virtual design process for a tight-fitting garment pattern for adapter consumer garments, aimed at consumers with scoliosis. The design process proposed is based on a virtual human model created using a 3D scanner, allowing simulation of the morphological shape of an individual with atypical physical deformations. Customized 2D and 3D virtual garment prototyping tools are used in combination to create products through interactions between the consumer, designer and pattern maker. After following an interactive sequence: Scanning – Design – Display – Evaluation – Adjustment, a final design solution acceptable to both the designer and consumer can be obtained. Through this process, traditional 2D garment design knowledge, especially design rules influenced by the fabric information, is fully utilized to support the design process proposed. Using the knowledge based collaborative design process, design satisfaction can be largely improved.

PL

W artykule przedstawiono wirtualny proces projektowania wzoru odzieży dla osób ze skoliozą. Zaproponowany projekt jest oparty na wirtualnym modelu ciała człowieka stworzonym przy użyciu skanera 3D, umożliwiającego symulację morfologicznego kształtu ciała osoby o nietypowych deformacjach fizycznych. Po wykonaniu sekwencji interaktywnej: skanowanie – projekt – wyświetlacz – ocena – dostosowanie, można uzyskać ostateczne rozwiązanie projektowe akceptowalne zarówno dla projektanta, jak i dla konsumentów. W tym procesie tradycyjna wiedza z zakresu zasad projektowania odzieży 2D jest w pełni wykorzystywana w celu wspierania zaproponowanego procesu projektowania. Korzystając z kombinacji obu systemów 2D i 3D można w znacznym stopniu poprawić jakość otrzymanego projektu. Udane rozwiązania projektowe można zintegrować z bazą wiedzy o projektowaniu mody, aby tworzyć nowe zasady projektowania i rozszerzać profesjonalną wiedzę dotyczącą projektowania.

7

Nutrient Uptake and Allocation by Plants in Recent Mounds Created by Subterranean Rodent, Plateau Zokor Eospalax baileyi

75%

Wu R. , Wei X. , Liu K. , Zhong M. , Liu Y. , Pan D. , Shao X.

Polish Journal of Ecology

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2017

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tom Vol. 65, nr 1

132--143

EN

To understand the nutrient absorption and adaptability of plant species that initially colonize mounds and the influences of the plateau zokor on the diversity of the plant community after 4 years' period, a series of experiments was conducted in an alpine meadow on the Qinghai-Tibetan Plateau. The contents of C and N and the flow of N in pioneer species were measured and tracked using the 15N isotope tracer method, and the species diversity on 4-year-old mounds was investigated. The results showed that (1) plateau zokors could influence the plant species on the mounds by creating gaps in the grassland; (2) Elymus nutans and Elsholtzia feddei, with high rates and efficiencies of nutrient absorption and transportation, were more competitive on the newly formed mounds than other species; (3) Elymus nutans played a dominant role in the plant community of the mounds; and (4) plateau zokors did not change the plant diversity after 4 years' period. These findings indicated that species colonizing the mounds experienced a process of competition when gaps were created by the rodents, that species with greater capabilities for resource acquisition and utilization had stronger competitiveness and vice versa, and that after a few years, the plant diversity on the mounds was almost similar to that of the undisturbed grassland.

8

Leaf morphology shift of three dominant species along altitudinal gradient in an alpine meadow of the Quinghai â Tibetan Plateau

63%

Zhong M. , Wang J. , Liu K. , Wu R. , Liu Y. , Wei X. , Pan D. , Shao X.

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2014

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tom Vol. 62, nr 4

639--648

EN

It has been observed that leaf morphology shift within species is linked to climate change, but there are few studies on the effects of altitude change on leaf morphology of species. We hypothesized that similar to climate change, a morphological shift within species would occur over time under different growing altitudes. In this study, we evaluated three dominant grass species: Elymus nutans Griseb., Kobresia capillifolia Clarke., Carex moorcroftii Boott., taking advantage of the altitudinal variations (3000-4000 a.s.l.) on the Qinghai-Tibetan Plateau. Our study showed that almost all leaf traits of these three species had significant differences (P <0.05) across an altitudinal gradient. Different species responded differently to altitude change. Leaf thickness (LT) of the three species increased with increase in altitude. Leaf area (LA) of E. nutans and C. moorcroftii decreased with increasing altitude, but that of K. capillifolia increased. There was no obvious linear effect on leaf dry matter content (LDMC) and specific leaf area (SLA) of these three species. LDMC of E. nutans and C. moorcroftii showed a trend of increase, while that of K. capillifolia decreased. SLA of E. nutans and K. capillifolia showed a trend of increase, but that of C. moorcroftii decreased with increase in altitude. In addition, soil pH (pH) and air temperature (AT) decreased with increase in altitude. However, other soil and climate factors increased as altitude increased. The finding of this work is that leaf morphology shift within species happens under altitude change to adapt to specific environment.

9

Leaf morphology shift of three dominant species along altitudinal gradient in an Alpine meadow of the Quinghai - Tibetan Plateau

63%

Zhong M. , Wang J. , Liu K. , Wu R. , Liu Y. , Wei X. , Pan D. , Shao X.

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nr 4

EN

It has been observed that leaf morphology shift within species is linked to climate change, but there are few studies on the effects of altitude change on leaf morphology of species. We hypothesized that similar to climate change, a morphological shift within species would occur over time under different growing altitudes. In this study, we evaluated three dominant grass species: Elymus nutans Griseb., Kobresia capillifolia Clarke., Carex moorcroftii Boott., taking advantage of the altitudinal variations (3000-4000 a.s.l.) on the Qinghai-Tibetan Plateau. Our study showed that almost all leaf traits of these three species had significant differences (P <0.05) across an altitudinal gradient. Different species responded differently to altitude change. Leaf thickness (LT) of the three species increased with increase in altitude. Leaf area (LA) of E. nutans and C. moorcroftii decreased with increasing altitude, but that of K. capillifolia increased. There was no obvious linear effect on leaf dry matter content (LDMC) and specific leaf area (SLA) of these three species. LDMC of E. nutans and C. moorcroftii showed a trend of increase, while that of K. capillifolia decreased. SLA of E. nutans and K. capillifolia showed a trend of increase, but that of C. moorcroftii decreased with increase in altitude. In addition, soil pH (pH) and air temperature (AT) decreased with increase in altitude. However, other soil and climate factors increased as altitude increased. The finding of this work is that leaf morphology shift within species happens under altitude change to adapt to specific environment.