Wyniki wyszukiwania - Biblioteka Nauki

1

Utilizing User Access Sequence to Mitigate the Cold Start Problem in Collaborative Filtering Recommendation

100%

Deng X.

Przegląd Elektrotechniczny

|

2013

|

tom R. 89, nr 1b

217--220

EN

Collaborative filtering (CF) is one of the most successful recommending techniques, but it suffers from the cold start problem which severely affected the quality of recommendation. To address this problem, we propose a novel hybrid approach, named UAS-CF, which incorporates user access sequence into traditional CF for improving the quality of recommendation. Experiments on three datasets were carried out to evaluate the performance of our method. Our results show that our approach outperforms other methods and improves recommendation quality effectively.

PL

W artykule zaprezentowano nowe podejście UAS-CF do obsługi poleceń, które włącza sekwencję dostępu użytkownika do klasycznego filtrowania uwspólnionego (ang. Collaborative Filtering), w celu polepszenia jakości rekomendacji. Badania eksperymentalne, przeprowadzone na trzech sekwencjach danych, wykazują wysoką jakość rekomendacji w porównaniu z innymi metodami.

2

A Multifaceted Analysis of Probabilistic Three-way Decisions

63%

Deng X. , Yao Y.

Fundamenta Informaticae

|

2014

|

tom Vol. 132, nr 3

291--313

EN

In situations where available information or evidence is incomplete or uncertain, probabilistic two-way decisions/classifications with a single threshold on probabilities for making either an acceptance or a rejection decision may be inappropriate. With the introduction of a third non-commitment option, probabilistic three-way decisions use a pair of thresholds and provide an effective and practical decision-making strategy. This paper presents a multifaceted analysis of probabilistic three-way decisions. By identifying an inadequacy of two-way decisions with respect to controlling the levels of various decision errors, we examine the motivations and advantages of three-way decisions. We present a general framework for computing the required thresholds of a three-way decision model as an optimization problem. We investigate two special cases, one is a decision-theoretic rough set model and the other is an information-theoretic rough set model. Finally, we propose a heuristic algorithm for finding the required thresholds.

3

A simple and practical color image encryption with the help of QR code

63%

Deng X. , Zhu X.

Optica Applicata

|

2015

|

tom Vol. 45, nr 4

513--521

EN

A simple and practical color image encryption is proposed with the help of quick response (QR) code. The original color image to be encoded is firstly transformed into the corresponding QR code, and then a joint transform correlator encrypting architecture is used to encode the corresponding QR code into a positive ciphertext. In the decryption, the corresponding QR code can be restored with the correct decryption key, and hence the original color image can be retrieved without any quality loss by scanning the restored QR code with a smartphone. Compared with the reported color image encryption techniques, the proposed technique does not need to convert color image (RGB) into indexed image formats or segregate into three color components prior to encryption and hence the corresponding reverse processes also are not required after decryption. Moreover, with the help of the QR code, the proposed method has strong tolerance to speckle noise and other noises resulting from optical system. In addition, the proposed method is practical because its ciphertext is a positive image and can be printed directly or manufactured as a card. The feasibility and effectiveness of the proposed method are demonstrated by numerical results.

4

Elastic-plastic analysis for circumferential through crack at boundary of semi’s brace under beam wave

51%

Wang F. , Deng X. , Li Y.

Polish Maritime Research

|

2018

|

tom nr 4

106--113

EN

In order to ensure the safety and reliability of the horizontal brace of semi-submersible platform (SEMI) which functions as the supporting structure in SEMI, this article presents an elastic-plastic method to analyze the variations of the crack tip opening displacement, elastic zone and plastic zone of the cracked section of the horizontal brace under beam wave. The brace of the SEMI was assumed to be located a circumferential through crack at its boundary in this article. In addition, the cracked section of the brace has been divided into crack zone, tensile plastic zone, elastic zone and compressive plastic zone in the presented theoretical model. Moreover, the closed form of the solution has been found in this article which is especially suitable solving complicated problems in practical engineering application. Also, a typical new-generation SEMI that is in practical use was selected to analyze the variation tendency of the cracked brace’s parameters using the proposed model which could give good suggestion to semi-submersible platform designers and managers.

5

Wpływ opóźniaczy węglowodanowych na ograniczenie złego wpływu minerałów ilastych na właściwości dyspergujące superplastyfikatorów polikarboksylanowych

51%

Tan H. , Deng X. , Gu B. , Ma B.

Cement Wapno Beton

|

2018

|

tom R. 21/83, nr 1

16--29

PL

W pracy zbadano wpływ węglowodanów sacharozy oraz maltodekstryny na skuteczność działania domieszek polikarboksylanowych w zaczynach zawierających montmorillonit. W tym celu oznaczano konsystencję zaczynów oraz oceniono stopień adsorpcji PCE oraz węglowodanów w zawiesinie montmorillonitu na podstawie całkowitej zawartości węgla organicznego. Oba węglowodany zmniejszały dodatek PCE potrzebny do uzyskania założonej płynności zaczynów o kilkanaście procent i ograniczały zmniejszanie się konsystencji w czasie. Zarówno sacharoza jak i maltodekstryna nie wbudowują się pomiędzy warstwy montmorillonitu, ale w niewielkim stopniu ograniczają interkalację PCE, najprawdopodobniej dzięki wiązaniom wodorowym cząsteczek węglowodanów z bocznymi łańcuchami poli(tlenku etylenu).

EN

The effect of two carbohydrate retarders i.e. sugar and maltodextrin on the clay tolerance of PCE was investigated in this study. The fluidity loss of cement-montmorillonite paste was tested to assess the clay tolerance of PCE. Adsorption of PCE and carbohydrate in montmorillonite suspension was assessed with Total Organic Carbon measurements. On the basis of several methods application the interaction of carbohydrates with montmorillonite was discussed. Carbohydrates addition is reducing the addition of PCE needed to reach the same initial fluidity level of cement paste. Also the consistency loss is decreased by addition of carbohydrates. The results showed that nor sugar neither maltodextrin can be intercalated between montmorillonite layers. However, they have a slight effect on hindering the intercalation of PCE, most probably, due to the hydrogen bonds between carbohydrate and long side chain of PEO.

6

Elastic-plastic analysis for circumferential through crac at boundary of semi's brace under beam wave

51%

Wang F. , Deng X. , Li Y.

Polish Maritime Research

|

2018

|

tom 25

|

nr 4

EN

In order to ensure the safety and reliability of the horizontal brace of semi-submersible platform (SEMI) which functions as the supporting structure in SEMI, this article presents an elastic-plastic method to analyze the variations of the crack tip opening displacement, elastic zone and plastic zone of the cracked section of the horizontal brace under beam wave. The brace of the SEMI was assumed to be located a circumferential through crack at its boundary in this article. In addition, the cracked section of the brace has been divided into crack zone, tensile plastic zone, elastic zone and compressive plastic zone in the presented theoretical model. Moreover, the closed form of the solution has been found in this article which is especially suitable solving complicated problems in practical engineering application. Also, a typical new-generation SEMI that is in practical use was selected to analyze the variation tendency of the cracked brace’s parameters using the proposed model which could give good suggestion to semi-submersible platform designers and managers

7

Light effect on carotenoids production and expression of carotenogenesis genes in citrus callus of four genotypes

51%

Gao H. , Xu J. , Liu X. , Deng X.

Acta Physiologiae Plantarum

|

2011

|

tom 33

|

nr 6

EN

Due to their theoretically identical genetic background, citrus callus and other plant tissues may share some mechanisms in the regulation of carotenogenesis. Thus, in order to gain further information on light regulation of carotenoids biosynthesis in citrus, the carotenoids and expression profiles of carotenogenesis in calluses of four citrus genotypes treated with light or dark were investigated. As a response to white light, results showed that carotenoids biosynthesis in callus of Red Marsh grapefruit (Citrus paradisi Macf.) was hampered, whereas callus of Tarocco blood orange (C. sinensis (L.) Osbeck) was sensitive to light by accumulating over 55% more carotenoids on average. Among the detected carotenoids, the biosynthesis of carotenes seemed to be more sensitive than that of xanthophylls. Expression profiles of eight carotenogenesis genes encoding phytoene synthase (PSY), phytoene desaturase (PDS), ζ-carotene desaturase (ZDS), carotenoids isomerase (CRTISO) etc. were investigated. Results revealed that PSY was up regulated in calluses of two sweet oranges, and down regulated in callus of Murcott tangor (C. reticulata × C. sinensis). Biochemical data in the three genotypes emphasized the PSY as a rate-limiting gene in the carotenogenesis. However, in the callus of Red Marsh grapefruit, PDS and ZDS might be the rate-limiting genes, and their transcripts were apparently inhibited by light, led to significant decreases in contents of β-carotene and total carotenoids irrelevant to transcription levels of PSY. Expression of CRTISO was light-induced, especially in the callus of Murcott tangor, and increased by nearly 12-fold. In conclusion, light regulates the expression of several carotenogenesis genes in citrus callus, but may not necessarily result in significant changes in carotenoids production.

8

Silicon increases salt tolerance by influencing the two-phase growth response to salinity in wheat (Triticum aestivum L.)

51%

Chen D. , Yin L. , Deng X. , Wang S.

Acta Physiologiae Plantarum

|

2014

|

tom 36

|

nr 09

EN

Salt usually stresses plants in two ways, osmotic stress and ion toxicity. Plant responds to salinity in two distinct phases through time. It is known that silicon (Si) could alleviate salt stress by decreasing the Na⁺ accumulated in the leaf. In order to determine the function of Si in the two-phase growth response (osmotic and ion toxicity) to salinity, we selected the wheat cultivar ‘‘Changwu 134’’ out of 10 wheat cultivars, and confirmed that it responds to salinity in two distinct phases through time. The fresh weight, leaf area, and leaf Na⁺ concentration were measured during 31 days of 120 mM NaCl supplemented with 1 mM Si treatment. The results revealed that the growth of plants under salinity conditions both with and without Si application were in accordance with the two-phase growth model. Si alleviated the salt stress in the both two-phase growth, but the alleviative effects were more pronounced in the osmotic stress phase than ion toxicity phase. These results clearly showed that Si can enhance plant salt tolerance by alleviating the salt-induced osmotic stress.

9

Application of Hilbert-Huang Transformation for Identifying the Fault Location on Series Compensated Lines

51%

Kong X. , Zhang Z. , Yin X. , Deng X.

Przegląd Elektrotechniczny

|

2013

|

tom R. 89, nr 5

135-140

EN

With the study on the transient state of series compensated lines under symmetrical and asymmetrical fault conditions, it’s obtained that low frequency component is much larger than aperiodic component of the measured transient current if the fault location is behind the series compensated capacitor. Due to the non-linear volt-ampere characteristics of MOV, the equivalent capacitive of series compensated device changes with time. Hence, the frequency of low frequency component caused by series compensated capacitor is time-varying. Hilbert-Huang Transformation is applied to analyze the instantaneous frequency and amplitude of the low frequency component to identify the fault location. The simulation results prove this method works.

PL

W artykule przedstawiono metodę lokalizacji awarii symetrycznych i niesymetrycznych w układach kompensacji szeregowej. Określono wpływ charakterystyki napięciowo-prądowej łącznika warystorowego na wartość harmonicznych niższego stopnia, wprowadzanych do sieci. Zastosowano transformację Hilbert-Huang w celu analizy chwilowej częstotliwości i amplitudy składowej niskiej częstotliwości oraz określenia miejsca awarii. Wykonano badania symulacyjne.

10

Impaired angiogenesis in aging myocardial microvascular endothelial cells is associated with reduced importin alpha and decreased nuclear transport of HIF1alpha: mechanistic implications

45%

Ahluwalia A. , Narula J. , Jones M. K. , Deng X. , Tarnawski A. S.

Journal of Physiology and Pharmacology

|

2010

|

tom 61

|

nr 2

EN

Aging is associated with increased incidence of myocardial infarctions and impaired angiogenesis - new capillary blood vessel formation from preexisting vessels. The molecular mechanism(s) of aging-related impairment of angiogenesis are unknown. In the present study we focused on the mechanism of activation of the gene for vascular endothelial growth factor (VEGF - the most potent stimulator of angiogenesis) in young and aging myocardial microvascular endothelial cells (MMEC). Activation of VEGF gene in the cell nucleus is mediated in part by the transcription factor hypoxia-inducible factor 1 (HIF1). In order to activate VEGF gene, HIF1 must first be transported to the nucleus, but the mechanisms of this transport are unknown. We hypothesized that reduced VEGF gene activation and impaired angiogenesis in myocardium during aging can result from downregulation of the nuclear transport receptor - importin that leads to decreased transport of HIF1 to the nucleus. We examined in MMEC isolated from young (3 months of age) and aging (24 months old) Fisher F-344 rats: 1) in vitro angiogenesis; and 2) the expression of VEGF, importin and HIF1. Aging MMEC exhibited a 3.7-fold reduction in angiogenesis and a corresponding reduction in VEGF (by 3-fold) and importin (by 1.9-fold) levels compared to young MMEC. Aging MMEC also exhibited cytoplasmic accumulation (by 1.8-fold) of HIF1 protein, reduced HIF1 transport to the nucleus and decreased binding of HIF1 protein to the VEGF gene promoter. This study is the first demonstration of the downregulation of importin in aging MMEC and reduced nuclear transport of HIF1, which likely lead to decreased VEGF gene activation and impaired angiogenesis.

11

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

45%

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

Polish Journal of Chemical Technology

|

2018

|

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.

12

Relaxor characteristics of ferroelectric BaZr0.2Ti0.8O3 ceramics

45%

Fu C. , Pan F. , Cai W. , Deng X. , Liu X.

Materials Science Poland

|

2009

|

tom Vol. 27, No. 3

891--897

EN

The crystalline microstructure, surface morphology, and the dielectric properties of BaZr0.2Ti0.8O3 (BZT) ceramics are investigated. From the X-ray diffraction pattern, it is found that the c-axis lattice parameter of the BZT ceramics is greater than the a-axis one. The temperature dependence of the electric permittivity indicates that there exists a diffuse transition in BZT ceramics. According to a modified Curie-Weiss law, it is calculated that the diffuseness constant (?) equals 1.93. From the hysteresis loops, it is found that the remanent polarization (2Pr) and the coercive field (2EC) of BZT ceramics both increase as the applied maximum voltage increases.

13

Comparative yield efficiencies of methyl bromide substitute fumigants and mulching systems for pepper production in the Southeast

45%

Fonsah E. , Yu Y. , Escalante C. , Culpepper S. , Deng X.

Journal of Agribusiness and Rural Development

|

2010

|

nr 01[15]

EN

Methyl Bromide (MB) is one of the most effective and widely used commercial chemicals in agriculture and non-agricultural sectors respectively. The decision to phaseout MB by 2005 set the stage for scientists to come up with a non-less-toxic replacement alternative or combinations thereof. This study focused on comparing yield efficiencies of different MB substitute fumigants and mulching systems for pepper production in the Southeast. Results of this study depicted that pepper production is potentially maximized under the tel-pic-vap treatment which is the only fumigation method that yielded significant differences relative to at least one other alternative approach.

PL

Bromek metylu (MB) jest jedną z najbardziej skutecznych i powszechnie stosowanych substancji chemicznych w rolnictwie i niektórych sektorach pozarolniczych. Decyzja w sprawie wycofania MB do 2005 roku zainspirowała naukowców do wynalezienia mniej toksycznych alternatyw dla tej substancji. Niniejsze opracowanie koncentruje się na porównywaniu efektywności fumigantów różnych alternatyw MB.

14

Reduced ghrelin in endothelial cells plays important mechanistic role in aging-related impairment of angiogenesis

45%

Ahluwalia A. , li A. , Cheng G. , Deng X. , Tarnawski A. S.

Journal of Physiology and Pharmacology

|

2009

|

tom 60

|

nr 2

29-34

EN

Ghrelin, a hormone produced mainly by gastric mucosal cells stimulates growth hormone (GH) release. Ghrelin is also expressed in the endothelial cells of blood vessels suggesting its physiological role and a function in these cells. We recently demonstrated that ghrelin induces angiogenesis - new capillary blood vessel formation- in neonatal human microvascular endothelial cells (HMVECs). Angiogenesis is impaired in aging individuals both in vitro and in vivo, but the precise mechanism(s) of this phenomenon is unknown. We examined whether HMVECs derived from aging individuals (66 years and 90 years old), 66-HMVECs and 90-HMVECs have reduced ghrelin levels vs. neonatal (Neo) HMVECs and whether treatment with exogenous ghrelin can restore impaired in vitro angiogenesis on matrigel in aged HMVECs. Ghrelin levels were reduced in the aged HMVECs by 3.2-fold (p<0.05) compared to Neo-HMVECs. Angiogenesis was significantly decreased in the aged 66- and 90-HMVECs by 39.7% (p = 0.003) and 62.4% (p = 0.003), respectively compared to Neo-HMVECs. Treatment with exogenous ghrelin significantly reversed impaired angiogenesis in aged HMVECs with the EC50 0.05 nM. Ghrelin induced angiogenesis in Neo-HMVECs mainly through ERK2 activation. This study is the first demonstration that reduced ghrelin is one of the factors responsible for aging-related impairment of angiogenesis.

15

Quantification of individual tree competition index taking Chinese-fir plantations in subtropical low hilly area as an example

38%

Zhang Y. , Deng X. , Huang Y. , Li Y. , Xiang W. , Yan W.

Polish Journal of Ecology

|

2019

|

tom 67

|

nr 1

EN

Competition among trees is a fundamental interaction process within plant community, which is the theoretical basis of thinning. Plant competitive intensity is generally measured using a competition index (CI) that can be classified into two major categories: distance-independent and distance-dependent. The current study used Cunninghamia lanceolata (Lamb.) Hook as the test subject and used Hegyi's CI (distance-dependent), to quantify individual CI and their relationship with tree diameter at breast height (DBH). Five different criteria were used to select potential competitors for the calculation of CI. Seven basic linear and nonlinear mathematical functions were used to test and quantify the relationships between DBH of the target tree and the individual CI. Results showed that individual CI was negatively correlated with target tree DBH: as DBH increased, competition intensity weakened. The adjusted R² with five different criteria of selection competitors simulated by seven functions ranged from 0.30 to 0.82. Considering the root mean square error (RMSE), P-value, and adjusted-R², our results suggested that the best model to simulate the relationship between individual CI and focal tree DBH was power function (CI = 43.98 × DBH⁻¹‧⁰⁸, adjusted R² = 0.81) and with the Voronoi diagram method as the criteria for selecting competitors. These results can demonstrate a clearer understanding of the spatial structure of forests, and can be used to guide the selection of thinning trees in the process of thinning practice.

16

Physiological mechanism of programmed cell death aggravation and acceleration in wheat endosperm cells caused by waterlogging

38%

Yu M. , Zhou Z. , Deng X. , Li J. , Mei F. , Qi Y.

Acta Physiologiae Plantarum

|

2017

|

tom 39

|

nr 01

17

Melatonin increased maize (Zea mays L.) seedling drought tolerance by alleviating drought-induced photosynthetic inhibition and oxidative damage

38%

Ye J. , Wang S. , Deng X. , Yin L. , Xiong B. , Wang X.

Acta Physiologiae Plantarum

|

2016

|

tom 38

|

nr 02

18

Transcriptome responses to phosphate deficiency in Poncirus trifoliata (L.) Raf

38%

Bai F. , Chen C. , An J. , Xiao S. , Deng X. , Pan Z.

Acta Physiologiae Plantarum

|

2014

|

tom 36

|

nr 12

EN

Phosphorus (P) is an essential macronutrient for plant growth and development; however, soil P available for plant absorption is often limited, putting constraints over agricultural sustainability. Understanding the physiological and molecular responses to P deficiency can help design strategies for diagnosis and mitigation of P deficiency in crop plants. The advent of the next-generation sequencing technologies has made it possible to characterize genome-wide molecular responses to P deficiency in plants. However, such research efforts are very limited for woody crops. In this study, RNA-seq was used to investigate P starvation-induced transcriptomic changes in roots of a frequently used citrus rootstock, Poncirus trifoliata (L.) Raf. A total of 1,135 genes showed differential expression in response to P deficiency. The transcriptomic data were further validated by real-time quantitative RT-PCR. Interestingly, at least one or more P-responsive cis-elements (P1BS) were found in the promoter regions of 76 differentially expressed genes. Functional annotation revealed that the predicted proteins of 117 of the differentially expressed genes were assigned to the categories of transporters, transcription factors or components involved in plant hormone signal regulation, suggesting that these genes may play important roles in response to P starvation. A comparative analysis of the citrus- and Arabidopsis-responsive transcripts under P deficiency also identified 174 commonly regulated genes, including those involved in P metabolism. Taken together, our transcriptomic data revealed changes of genome-wide gene expression in responses to P starvation in Poncirus, which should provide a solid basis for future identification and characterization of key genes involved in nutritional stress response in citrus rootstocks.

19

Comparative study of the leaf transcriptomes and ionoms of Juglans regia and its wild relative species Juglans cathayensis

38%

Zhou Z. , Han M. , Hou M. , Deng X. , Tian R. , Min S. , Zhang J.

Acta Physiologiae Plantarum

|

2017

|

tom 39

|

nr 10

20

Identification, evolution and expression analyses of Ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit gene family in wheat (Triticum aestivum L.)

38%

Qin L. , Xue Y. , Fei Y. , Zeng L. , Yang S. , Deng X.

Acta Physiologiae Plantarum

|

2018

|

tom 40

|

nr 05