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Adaptive enhancement design of triply periodic minimal surface lattice structure based on non-uniform stress distribution
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作者 Yijin ZHANG Bin LIU +5 位作者 Fei PENG Heran JIA Zeang ZHAO Shengyu DUAN Panding WANG Hongshuai LEI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第8期1317-1330,共14页
The Schwarz primitive triply periodic minimal surface(P-type TPMS)lattice structures are widely used.However,these lattice structures have weak load-bearing capacity compared with other cellular structures.In this pap... The Schwarz primitive triply periodic minimal surface(P-type TPMS)lattice structures are widely used.However,these lattice structures have weak load-bearing capacity compared with other cellular structures.In this paper,an adaptive enhancement design method based on the non-uniform stress distribution in structures with uniform thickness is proposed to design the P-type TPMS lattice structures with higher mechanical properties.Two types of structures are designed by adjusting the adaptive thickness distribution in the TPMS.One keeps the same relative density,and the other keeps the same of non-enhanced region thickness.Compared with the uniform lattice structure,the elastic modulus for the structure with the same relative density increases by more than 17%,and the yield strength increases by more than 10.2%.Three kinds of TPMS lattice structures are fabricated by laser powder bed fusion(L-PBF)with 316L stainless steel to verify the proposed enhanced design.The manufacture-induced geometric deviation between the as-design and as-printed models is measured by micro X-ray computed tomography(μ-CT)scans.The quasi-static compression experimental results of P-type TPMS lattice structures show that the reinforced structures have stronger elastic moduli,ultimate strengths,and energy absorption capabilities than the homogeneous P-TPMS lattice structure. 展开更多
关键词 additive manufacturing(AM) triply periodic minimal surface(TPMS) enhanced design model mechanical property micro X-ray computed tomography(u-CT)
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Enhanced Security with Improved Defensive Routing Mechanism in Wireless Sensor Networks
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作者 R.Sabitha C.Gokul Prasad S.Karthik 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2795-2810,共16页
In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of W... In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of WSNs are distributed in an intimidating region,which is non-rigid to attacks.The recent research domains of WSN deal with models to handle the WSN communications against malicious attacks and threats.In traditional models,the solution has been made for defending the networks,only to specific attacks.However,in real-time applications,the kind of attack that is launched by the adversary is not known.Additionally,on developing a security mechanism for WSN,the resource constraints of sensor nodes are also to be considered.With that note,this paper presents an Enhanced Security Model with Improved Defensive Routing Mechanism(IDRM)for defending the sensor network from various attacks.Moreover,for efficient model design,the work includes the part of feature evaluation of some general attacks of WSNs.The IDRM also includes determination of optimal secure paths and Node security for secure routing operations.The performance of the proposed model is evaluated with respect to several factors;it is found that the model has achieved better security levels and is efficient than other existing models in WSN communications.It is proven that the proposed IDRM produces 74%of PDR in average and a minimized packet drop of 38%when comparing with the existing works. 展开更多
关键词 Enhanced security model wireless sensor networks improved defensive routing mechanism secure paths node security
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Computer-based Creativity Enhanced Conceptual Design Model for Non-routine Design of Mechanical Systems 被引量:5
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作者 LI Yutong WANG Yuxin DUFFY Alex H B 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1083-1098,共16页
Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(... Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(FBS) model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model(CECD) for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions(BOA), and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem. 展开更多
关键词 conceptual design non-routine design creative enhance model computer-based approach mathematical expression
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Reduced EGFR signaling enhances cartilage destruction in a mouse osteoarthritis model 被引量:9
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作者 Xianrong Zhang Ji Zhu +6 位作者 Fei Liu Yumei Li Abhishek Chandra L Scott Levin Frank Beier Motomi Enomoto-Iwamoto Ling Qin 《Bone Research》 SCIE CAS 2014年第3期182-193,共12页
Osteoarthritis (OA) is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor (EGFR) signaling as an important regulat... Osteoarthritis (OA) is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor (EGFR) signaling as an important regulator of cartilage matrix degradation during epiphyseal cartilage development. To study its function in OA progression, we performed surgical destabilization of the medial meniscus (DMM) to induce OA in two mouse models with reduced EGFR activity, one with genetic modification (, was/+ mice) and the other one with pharmacological inhibition (gefitinib treatment). Histological analyses and scoring at 3 months post-surgery revealed increased cartilage destruction and accelerated OA progression in both mouse models. TUNEL staining demonstrated that EGFR signaling protects chondrocytes from OA-induced apoptosis, which was further confirmed in primary chondrocyte culture. Immunohistochemistry showed increased aggrecan degradation in these mouse models, which coincides with elevated amounts of ADAMTS5 and matrix metalloproteinase 13 (MMP13), the principle proteinases responsible for aggrecan degradation, in the articular cartilage after DMM surgery. Furthermore, hypoxia-inducible factor 2α (HIF2α), a critical catabolic transcription factor stimulating MMP13 expression during OA, was also upregulated in mice with reduced EGFR signaling. Taken together, our findings demonstrate a primarily protective role of EGFR during OA progression by regulating chondrocyte survival and cartilage degradation. 展开更多
关键词 EGFR Reduced EGFR signaling enhances cartilage destruction in a mouse osteoarthritis model
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Local icariin application enhanced periodontal tissue regeneration and relieved local inflammation in a minipig model of periodontitis 被引量:9
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作者 Xiuli Zhang Nannan Han +4 位作者 Guoqing Li Haoqing Yang Yangyang Cao Zhipeng Fan Fengqiu Zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第3期168-173,共6页
Periodontitis is an inflammatory autoimmune disease. Treatment should alleviate inflammation, regulate the immune reaction and promote periodontal tissue regeneration. Icariin is the main active ingredient of Epimedii... Periodontitis is an inflammatory autoimmune disease. Treatment should alleviate inflammation, regulate the immune reaction and promote periodontal tissue regeneration. Icariin is the main active ingredient of Epimedii Folium, and it is a promising compound for the enhancement of mesenchymal stem cell function, promotion of bone formation, inhibition of bone resorption, alleviation of inflammation and regulation of immunity. The study investigated the effect of icariin on periodontal tissue regeneration in a minipig model of periodontitis. The minipig model of periodontitis was established. Icariin was injected locally. The periodontal clinical assessment index, a computed tomography(CT) scan, histopathology and enzyme-linked immune sorbent assay(ELISA)were used to evaluate the effects of icariin. Quantitative analysis results 12 weeks post-injection demonstrated that probing depth,gingival recession, attachment loss and alveolar bone regeneration values were(3.72 ± 1.18) mm vs.(6.56 ± 1.47) mm,(1.67 ± 0.59)mm vs.(2.38 ± 0.61) mm,(5.56 ± 1.29) mm vs.(8.61 ± 1.72) mm, and(25.65 ± 5.13) mm3 vs.(9.48 ± 1.78) mm3 in the icariin group and0.9% NaCl group, respectively. The clinical assessment, CT scan, and histopathology results demonstrated significant enhancement of periodontal tissue regeneration in the icariin group compared to the 0.9% NaCl group. The ELISA results suggested that the concentration of interleukin-1 beta(IL-1β) in the icariin group was downregulated compared to the 0.9% NaCl group, which indicates that local injection of icariin relieved local inflammation in a minipig model of periodontitis. Local injection of icariin promoted periodontal tissue regeneration and exerted anti-inflammatory and immunomodulatory function. These results support the application of icariin for the clinical treatment of periodontitis. 展开更多
关键词 Local icariin application enhanced periodontal tissue regeneration and relieved local inflammation in a minipig model of periodontitis ELISA
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Optical Absorption Enhancement Effects of Silver Nanodisk Arrays in the Application of Silicon Solar Cell 被引量:1
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作者 Xiao-Ping Huang Zao-Jin Zeng Lei Zhong Dan Wu Fang-Chun Yan 《Journal of Electronic Science and Technology》 CAS 2011年第1期35-40,共6页
Surface plasmon resonance of noble metal nanoparticles leads to the optical absorption enhancement effects,which have great potential applications in solar cell.By using the general numerical method of discrete dipole... Surface plasmon resonance of noble metal nanoparticles leads to the optical absorption enhancement effects,which have great potential applications in solar cell.By using the general numerical method of discrete dipole approximation (DDA),we study the absorption and scattering properties of two-dimensional square silver nanodisks (2D SSN) arrays on the single crystal silicon solar cell.Based on the effective reflective index model of the single crystal silicon solar cell,we investigate the optical enhancement absorption of light energy by varying the light incident direction,particle size,aspect ratio,and interparticle spacing of the silver nanodisks.The peak values and position of the optical extinction spectra of the 2D square arrays of noble metal nanodisks are obtained with the different array structures. 展开更多
关键词 Effective reflective index model optical absorption enhancement effects silicon solar cell two-dimensional square silver nanodisks arrays.
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Comparison of Space Glucose Control and Routine Glucose Management Protocol for Glycemic Control in Critically Ⅲ Patients: A Prospective, Randomized Clinical Study 被引量:4
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作者 Biao Xu Wei Jiang +4 位作者 Chun-Yao Wang Li Weng Xiao-Yun Hu Jin-Min Peng Bin Du 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第17期2041-2049,共9页
Background:The Space Glucose Control (SGC) system is a computer-assisted device combining infusion pumps with the enhanced Model Predictive Control algorithm to achieve the target blood glucose (BG) level safely.... Background:The Space Glucose Control (SGC) system is a computer-assisted device combining infusion pumps with the enhanced Model Predictive Control algorithm to achieve the target blood glucose (BG) level safely.The objective of this study was to evaluate the efficacy and safety of glycemic control by SGC with customized BG target range of 5.8-8.9 mmol/L in the critically ill patients.Methods:It is a randomized controlled trial of seventy critically ill patients with mechanical ventilation and hyperglycemia (BG 〉 9.0 mmol/L).Thirty-six patients in the SGC group and 34 in the routine glucose management group were observed for three consecutive days.Target BG for both groups was 5.8-8.9 mmol/L.The primary outcome was the percentage time in the target range.Results:The percentage time within BG target range in the SGC group (69 &#177; 15%) was significantly higher than in the routine management group (52 &#177; 24%;P 〈 0.01).No measurement was 〈2.2 mmol/L,and there was only one episode of hypoglycemia (2.3-3.3 mmol/L) in each group.The average BG was significantly lower in the SGC group (7.8 &#177; 0.7 mmol/L) than in the routine management group (9.1 &#177; 1.6 mmol/L,P 〈 0.001).Target BG level was reached earlier in the SGC group than routine management group (2.5 &#177; 2.9 vs.12.1 &#177; 15.3 h,P =0.001).However,the SGC group performed worse for daily insulin requirement (59.8 &#177; 39.3 vs.28.4 &#177; 36.7 U,P =0.001)and sampling interval (2.0 &#177; 0.5 vs.3.7 &#177; 0.5 h,P 〈 0.001) than the routine management group did.Multiple linear regression showed that the intervention group remained a significant individual predictor (P 〈 0.001) of the percentage time in target range.Conclusions:The SGC system,with a BG target of 5.8-8.9 mmol/L,resulted in effective and reliable glycemic control with few hypoglycemic episodes in critically ill patients with mechanical ventilation and hyperglycemia.However,the workload was increased.Trial Registration:http://www.clinicaltrials.gov,NCT 02491346;https://www.clinicaltrials.gov/ct2/show/NCT02491346?term=NCT0 2491346&amp;cond=Hyperglycemia&amp;cntry1=ES%3ACN&amp;rank=1. 展开更多
关键词 Critical Illness: Glucose Control in Intensive Care HYPERGLYCEMIA Space Glucose Control Enhanced Model Predictive Control
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Activity-based simulation using DEVS: increasing performance by an activity model in parallel DEVS simulation
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作者 Bin CHEN Lao-bing ZHANG +1 位作者 Xiao-cheng LIU Hans VANGHELUWE 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2014年第1期13-30,共18页
Improving simulation performance using activity tracking has attracted attention in the modeling field in recent years.The reference to activity has been successfully used to predict and promote the simulation perform... Improving simulation performance using activity tracking has attracted attention in the modeling field in recent years.The reference to activity has been successfully used to predict and promote the simulation performance.Tracking activity,however,uses only the inherent performance information contained in the models.To extend activity prediction in modeling,we propose the activity enhanced modeling with an activity meta-model at the meta-level.The meta-model provides a set of interfaces to model activity in a specific domain.The activity model transformation in subsequence is devised to deal with the simulation difference due to the heterogeneous activity model.Finally,the resource-aware simulation framework is implemented to integrate the activity models in activity-based simulation.The case study shows the improvement brought on by activity-based simulation using discrete event system specification(DEVS). 展开更多
关键词 Activity tracking Activity enhanced modeling Discrete event system specification(DEVS) Resource-aware simulation framework
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General Theoretical Model for Resonantly Enhanced Optical Modulators
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作者 Yuvaraja S. Visagathilagar Arnan Mitchell Michael W. Austin 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期337-338,共2页
1 IntroductionLiNbO3 optical modulators have become essential transmission devices for current and future wideband fibre-optic communications for both military and telecommunications applications. For many telecommuni... 1 IntroductionLiNbO3 optical modulators have become essential transmission devices for current and future wideband fibre-optic communications for both military and telecommunications applications. For many telecommunications applications, only a narrow bandwidth is required and thus resonantly enhancedMach-Zehndermodulators(RE-MZMs)have been developed to improve modulation efficiency at the expense of bandwidth. 展开更多
关键词 for on ET of in BE General Theoretical Model for Resonantly Enhanced Optical Modulators MZM
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Enhancement of solar cells parameters by periodic nanocylinders
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作者 Najdia Benaziez Abdelhamid Ounissi Safia Benaziez 《Journal of Semiconductors》 EI CAS CSCD 2016年第6期64-71,共8页
Optical absorption in thin-film solar cells can be improved by using surface plasmons for guiding and confining the light on the nanoscale.We report theoretical and simulation studies of a-Si thin-film solar cells wit... Optical absorption in thin-film solar cells can be improved by using surface plasmons for guiding and confining the light on the nanoscale.We report theoretical and simulation studies of a-Si thin-film solar cells with silver nanocylinders on the surface.We found that surface plasmons increased the cells' spectral response over almost the entire studied solar spectrum.In the ultraviolet range and at wavelengths close to the Si band gap we observed a significant enhancement of the absorption for both thin-film and wafer-based structures.We also performed optimization studies of particle size,inter-particle distance,and dielectric environment,for obtaining maximal absorption within the substrate.A blue-shift of the resonance wavelength with increasing inter-particle distance was observed in the visible range.Cell performance improved at optimal spacing,which strongly depended on the nanoparticle size.Increasing the nanocylinder size was accompanied by the widening of the plasmon resonance band and a red-shift of the plasmon resonance peaks.A weak red-shift and plasmon peak enhancement were observed in the reflectance curve with increasing refractive index of the dielectric spacer. 展开更多
关键词 plasmonic solar cell enhancement of absorption nanostructures transfer matrix method Maxwell-Garnett's model
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A method of whispered speech enhancement based on speech absence probability and modified mel-domain masking model
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作者 TAO Zhi~(1,2) ZHAO Heming~2 WU Di~1 CHEN Daqing~1 ZHANG Xiaojun~1 (1 School of Physical Science and Technology,Soochow University Suzhou 215006) (2 School of Electronics and Information Engineering,Soochow University Suzhou 215006) 《Chinese Journal of Acoustics》 2011年第3期345-357,共13页
Whispered speech enhancement using auditory masking model in modified Mel- domain and Speech Absence Probability (SAP) was proposed. In light of the phonation char- acteristic of whisper, we modify the Mel-frequency... Whispered speech enhancement using auditory masking model in modified Mel- domain and Speech Absence Probability (SAP) was proposed. In light of the phonation char- acteristic of whisper, we modify the Mel-frequency Scaling model. Whispered speech is filtered by the proposed model. Meanwhile, the value of masking threshold for each frequency band is dynamically determined by speech absence probability. Then whispered speech enhancement is conducted by adaptively rectifying the spectrum subtraction coefficients using different masking threshold values. Results of objective and subjective tests on the enhanced whispered signal show that compared with other methods; the proposed method can enhance whispered signal with better subjective auditory quality and less distortion by reducing the music noise and background noise under the masking threshold value. 展开更多
关键词 A method of whispered speech enhancement based on speech absence probability and modified mel-domain masking model Mel
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