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INDEPENDENTLY-TUNED CONCURRENT DUAL-BAND BRANCH-LINE COUPLER USING VARACTOR 被引量:1
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作者 Guo Xiaofeng Ye Yan +2 位作者 Liu Taijun Xu Qian Li Ruiyang 《Journal of Electronics(China)》 2014年第4期348-353,共6页
This paper presents a concurrent dual-band branch-line coupler with an independently tunable center frequency. In the proposed architecture, the quarter-wavelength lines, which work at two separated bands concurrently... This paper presents a concurrent dual-band branch-line coupler with an independently tunable center frequency. In the proposed architecture, the quarter-wavelength lines, which work at two separated bands concurrently and can be tuned in one of them, are key components. Based on the analysis of ABCD-matrix, a novel hybrid structure and a pair of varactors topology are utilized to achieve concurrent dual-band operation and independent tunability, respectively. Using this configuration, it is convenient to tune the center frequency of the upper band, while the responses of the lower band remain unaltered. To verify the proposed idea, a demonstration is implemented and the simulated results are presented. 展开更多
关键词 Branch-line coupler concurrent dual-band VARACTOR Independently tuned Quarter-wavelength lineCLC number:TN92
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NONLINEAR CHARACTERIZATION OF CONCURRENT DUAL-BAND RF POWER AMPLIFIERS
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作者 Hui Ming Liu Taijun +3 位作者 Ye Yan Zhang Haili Shen Dongya Li Liang 《Journal of Electronics(China)》 2012年第3期215-221,共7页
In this paper, the synchronous concurrent dual-band RF signal is used to drive the RF Power Amplifier (PA). The nonlinear characterization of a concurrent dual-band RF PA is discussed while two band signals in the dua... In this paper, the synchronous concurrent dual-band RF signal is used to drive the RF Power Amplifier (PA). The nonlinear characterization of a concurrent dual-band RF PA is discussed while two band signals in the dual-band are modulated by CDMA2000 and WCDMA signals. When the two band signals in the dual-band of the PA are modulated with the same signals, it is found that the nonlinearity of the PA can be expressed by any of the two corresponding baseband data. On the other hand, when the two band signals in the dual-band of the PA are modulated with two different signals, the PA nonlinearity cannot be characterized by any of the two corresponding baseband data. In this case, its nonlinearity has to be denoted by a composite signals consisting of the two baseband signals. Consequently, the requirements for the speed of the A/D converter can be largely reduced. The experimental results with CDMA2000 and WCDMA signals demonstrate the speed of the A/D converter required is only 30 M Sample Per Second (SaPS), but it will be at least 70 M SaPS for the conventional method. 展开更多
关键词 concurrent dual-band Power Amplifier (PA) Nonlinear characterization Digital base-band Pre-Distortion (DPD)
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Anthropogenic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s 被引量:1
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作者 Qin SU Buwen DONG +1 位作者 Fangxing TIAN Nicholas P.KLINGAMAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期233-246,共14页
The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characteriz... The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the present day(PD,1994–2011) is double that in the early period(EP, 1964–81);the duration of HDEs increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to HDE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HDE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HDEs to GHG and AA changes are also revealed. 展开更多
关键词 concurrent hot and dry events decadal variation greenhouse gases aerosol emissions
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Survival benefit of concurrent chemoradiotherapy for advanced ampulla of Vater cancer
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作者 Chae Hwa Kwon Hyung Il Seo +7 位作者 Dong Uk Kim Sung Yong Han Suk Kim Nam Kyung Lee Seung Baek Hong Ji Hyun Ahn Young Mok Park Byeong Gwan Noh 《World Journal of Clinical Cases》 SCIE 2024年第2期267-275,共9页
BACKGROUND Currently,there is no standard adjuvant therapy for patients with resected ampulla of Vater(AoV)cancer.AIM To evaluate the effectiveness of adjuvant concurrent chemoradiotherapy(CCRT)in patients with advanc... BACKGROUND Currently,there is no standard adjuvant therapy for patients with resected ampulla of Vater(AoV)cancer.AIM To evaluate the effectiveness of adjuvant concurrent chemoradiotherapy(CCRT)in patients with advanced AoV cancer who underwent curative resection.METHODS This single-centered,retrospective study included 29 patients with advanced AoV cancer who underwent pancreaticoduodenectomy between 2006 and 2018.The impact of CCRT on advanced AoV cancer was analyzed.RESULTS The 1-,3-,and 5-yr recurrence-free survival(RFS)rates for patients with advanced AoV cancer were 82.8%,48.3%,and 40.8%,respectively,and the overall survival(OS)rates were 89.7%,62.1%,and 51.7%,respectively.Lymphovas-cular invasion was found to be a significant risk factor for RFS and OS in patients with advanced AoV cancer in the univariate analysis,whereas T stage and lymph node metastasis were significantly associated with OS in the multivariate analysis.Compared to the patients who did not receive adjuvant CCRT,those who received adjuvant CCRT did not show statistically significant improvements in the RFS and OS,although they had a significantly lower average age and significantly higher platelet-to-lymphocyte ratio.CONCLUSION Adjuvant CCRT did not improve survival outcomes in patients with advanced AoV cancer.These findings contribute to existing knowledge on the effectiveness of CCRT in this patient population and provide important insights for clinical decision-making. 展开更多
关键词 Advanced ampulla of Vater cancer Adjuvant concurrent chemoradiotherapy RECURRENCE SURVIVAL Vater cancer
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Programmed cell death 1 inhibitor sintilimab plus concurrent chemoradiotherapy for locally advanced pancreatic adenocarcinoma
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作者 Shi-Qiong Zhou Peng Wan +3 位作者 Sen Zhang Yuan Ren Hong-Tao Li Qing-Hua Ke 《World Journal of Clinical Oncology》 2024年第7期859-866,共8页
BACKGROUND Pancreatic adenocarcinoma,a malignancy that arises in the cells of the pancreas,is a devastating disease with unclear etiology and often poor prognosis.Locally advanced pancreatic cancer,a stage where the t... BACKGROUND Pancreatic adenocarcinoma,a malignancy that arises in the cells of the pancreas,is a devastating disease with unclear etiology and often poor prognosis.Locally advanced pancreatic cancer,a stage where the tumor has grown significantly but has not yet spread to distant organs,presents unique challenges in treatment.This article aims to discuss the current strategies,challenges,and future directions in the management of locally advanced pancreatic adenocarcinoma(LAPC).AIM To investigate the feasibility and efficacy of programmed cell death 1(PD-1)inhibitor sintilimab plus concurrent chemoradiotherapy for LAPC.METHODS Eligible patients had LAPC,an Eastern cooperative oncology group performance status of 0 or 1,adequate organ and marrow functions,and no prior anticancer therapy.In the observation group,participants received intravenous sintilimab 200 mg once every 3 wk,and received concurrent chemoradiotherapy(concurrent conventional fractionated radiotherapy with doses planning target volume 50.4 Gy and gross tumor volume 60 Gy in 28 fractions and oral S-140 mg/m2 twice daily on days 1-14 of a 21-d cycle and intravenous gemcitabine 1000 mg/m2 on days 1 and 8 of a 21-d cycle for eight cycles until disease progression,death,or unacceptable toxicity).In the control group,participants only received concurrent chemoradiotherapy.From April 2020 to November 2021,64 participants were finally enrolled with 34 in the observation group and 30 in the control group.RESULTS Thirty-four patients completed the scheduled course of chemoradiotherapy,while 32(94.1%)received sintilimab plus concurrent chemoradiotherapy with 2 patients discontinuing sintilimab in the observation group.Thirty patients completed the scheduled course of chemoradiotherapy in the control group.Based on the Response Evaluation Criteria in Solid Tumors guidelines,the analysis of the observation group revealed that a partial response was observed in 11 patients(32.4%),stable disease was evident in 19 patients(55.9%),and 4 patients(11.8%)experienced progressive disease;a partial response was observed in 6(20.0%)patients,stable disease in 18(60%),and progressive disease in 6(20%)in the control group.The major toxic effects were leukopenia and nausea.The incidence of severe adverse events(AEs)(grade 3 or 4)was 26.5%(9/34)in the observation group and 23.3%(7/30)in the control group.There were no treatment-related deaths.The observation group demonstrated a significantly longer median overall survival(22.1 mo compared to 15.8 mo)(P<0.05)and progression-free survival(12.2 mo vs 10.1 mo)(P<0.05)in comparison to the control group.The occurrence of severe AEs did not exhibit a statistically significant difference between the observation group and the control group(P>0.05).CONCLUSION Sintilimab plus concurrent chemoradiotherapy was effective and safe for LAPC patients,and warrants further investigation. 展开更多
关键词 IMMUNOTHERAPY concurrent chemoradiotherapy Locally advanced pancreatic adenocarcinoma Programmed cell death 1 Sintilimab
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Miniaturized single-channel concurrent dual-band mixing architecture with one frequency-divided local oscillator
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作者 Yu Cuiping Gao Yuan +1 位作者 Wu Fan Liu Yuanan 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2019年第4期1-7,共7页
Concurrent dual-band transceiver system is widely used in conditions where transceivers are required to work in different bands at the same time.In order to miniaturize the concurrent dual-band transceiver system and ... Concurrent dual-band transceiver system is widely used in conditions where transceivers are required to work in different bands at the same time.In order to miniaturize the concurrent dual-band transceiver system and reduce the number of components in a transceiver,a novel receiver mixing structure with one frequency-divided local oscillator is proposed.Compared to traditional mixing architecture with two local oscillators,the proposed structure reduces a local oscillator and a bandpass filter.In addition,the output signal of proposed mixing architecture has a better error vector magnitude(EVM)performance.The proposed mixing architecture is described in detail;the method of local oscillator signal frequency selection and the applicable conditions of the proposed structure are derived through math formula;and the conclusions are demonstrated by experimental results. 展开更多
关键词 concurrent dual-band RECEIVERS nonlinear systems low system complexity MIXING
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Low-cost FPGA implementation of 2D digital pre-distorter for concurrent dual-band power amplifier
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作者 Zeng Guang Yu Cuiping +1 位作者 Li Shulan Liu Yuan'an 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2016年第1期14-21,共8页
This paper proposes a low-cost hardware architecture based on concurrent dual-band digital pre-distorter (DPD). The architecture is implemented on field programmable gate array (FPGA) to compensate for the nonline... This paper proposes a low-cost hardware architecture based on concurrent dual-band digital pre-distorter (DPD). The architecture is implemented on field programmable gate array (FPGA) to compensate for the nonlinearity of the concurrent dual-band power amplifier (PA). This implementation introduces a novel model complexity reduction technique into system, namely, time-division multiplexing for out-of-band lookup tables (LUTs) sharing. Performances are evaluated with an experimental test setup using a wideband class-F PA. The dual-band signal center frequency separated by 80 MHz. Lower and upper center frequency are located at 2.61 GHz and 2.69 GHz, respectively. This novel DPD implementation maintains excellent performance, but uses hardware resources reduced by 29.17% compared with conventional approaches. The results show that the adjacent channel power ratio (ACPR) is less than -59 dBc and normalized mean square error (NMSE) is around - 62dB for lower sideband (LSB) and - 63dB for upper sideband (USB). 展开更多
关键词 power amplifier concurrent dual-band digital predistorter lookup table field programmable gate array (FPGA)
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Design and implementation of a high-efficiency concurrent dual-band power amplifier
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作者 YANG Qian-kun LIU Yuan-an +2 位作者 YU Cui-ping LI Shu-lan LI Jiu-chao 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2014年第6期94-99,共6页
This paper studies the behaviors of power amplifier(PA) driven by a single-carrier continuous wave(CW) signal and a two-carrier CW signal both in theory and simulation, and explains why the traditional dual-band P... This paper studies the behaviors of power amplifier(PA) driven by a single-carrier continuous wave(CW) signal and a two-carrier CW signal both in theory and simulation, and explains why the traditional dual-band PA failed to perform satisfactory results when a two-carrier CW signal is applied to, called concurrently. Besides that, an evaluation standard of concurrent dual-band PA was presented to value its performance. Solution was given with design and fabrication of a concurrent 1.85 GHz/2.65 GHz class F PA, employing a 10 W GaN HEMT device from Cree, CGH40010, whose measurement shows the saturated output power is 40.6 d Bm and 40.8dB m with drain efficiencies(DE) of 77.4% and 75.3% at 1.85 GHz and 2.65 GHz, respectively. On the other hand, we see that the peak DE achieves 59.7% with an output power of 39.9 dB m in concurrent mode, which follows up with the standard. 展开更多
关键词 PA concurrent dual-band intermodulation and harmonic high efficiency
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Efficacy of concurrent chemoradiotherapy with thalidomide and S-1 for esophageal carcinoma and its influence on serum tumor markers 被引量:1
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作者 Tian-Wei Zhang Peng Zhang +3 位作者 Dong Nie Xin-Yu Che Tian-Tai Fu Yan Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第7期1262-1270,共9页
BACKGROUND Although the current conventional treatment strategies for esophageal carcinoma(EC)have been proven effective,they are often accompanied by serious adverse events.Therefore,it is still necessary to continue... BACKGROUND Although the current conventional treatment strategies for esophageal carcinoma(EC)have been proven effective,they are often accompanied by serious adverse events.Therefore,it is still necessary to continue to explore new therapeutic strategies for EC to improve the clinical outcome of patients.AIM To elucidate the clinical efficacy of concurrent chemoradiotherapy(CCRT)with thalidomide(THAL)and S-1(tegafur,gimeracil,and oteracil potassium capsules)in the treatment of EC as well as its influence on serum tumor markers(STMs).METHODS First,62 patients with EC treated at the Zibo 148 Hospital between November 2019 and November 2022 were selected and grouped according to the received treatment.Among these,30 patients undergoing CCRT with cis-platinum and 5-fluorouracil were assigned to the control group(Con),and 32 patients receiving CCRT with THAL and S-1 were assigned to the research group(Res).Second,inter-group comparisons were carried out with respect to curative efficacy,incidence of drug toxicities,STMs[carbohydrate antigen 125(CA125)and macrophage inflammatory protein-3α(MIP-3α)],angiogenesis-related indicators[vascular endothelial growth factor(VEGF);VEGF receptor-1(VEGFR-1);basic fibroblast growth factor(bFGF);angiogenin-2(Ang-2)],and quality of life(QoL)[QoL core 30(QLQ-C30)]after one month of treatment.RESULTS The analysis showed no statistical difference in the overall response rate and disease control rate between the two patient cohorts;however,the incidences of grade I–II myelosuppression and gastrointestinal reactions were significantly lower in the Res than in the Con.Besides,the post-treatment CA125,MIP-3α,VEGF,VEGFR-1,bFGF,and Ang-2 Levels in the Res were markedly lower compared with the pre-treatment levels and the corresponding post-treatment levels in the Con.Furthermore,more evident improvements in QLQ-C30 scores from the dimensions of physical,role,emotional,and social functions were determined in the Res.CONCLUSION The above results demonstrate the effectiveness of THAL+S-1 CCRT for EC,which contributes to mild side effects and significant reduction of CA125,MIP-3α,VEGF,VEGFR-1,bFGF,and Ang-2 Levels,thus inhibiting tumors from malignant progression and enhancing patients’QoL. 展开更多
关键词 THALIDOMIDE concurrent chemoradiotherapy Esophageal carcinoma Therapeutic effect Serum tumor markers
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Concurrent Multi-die Optimization物理实现方案的应用
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作者 黄彤彤 陈昊 +5 位作者 武辰飞 许立新 徐国治 李玉童 周国华 欧阳可青 《电子技术应用》 2023年第8期30-35,共6页
随着芯片制造工艺不断接近物理极限,使用多die堆叠的3DIC Chiplets设计已经成为延续摩尔定律的最佳途径之一。Integrity 3D-IC平台将设计规划、物理实现和系统分析统一集成于单个管理界面中,为3D设计提供了系统完善的解决方案。其中传统... 随着芯片制造工艺不断接近物理极限,使用多die堆叠的3DIC Chiplets设计已经成为延续摩尔定律的最佳途径之一。Integrity 3D-IC平台将设计规划、物理实现和系统分析统一集成于单个管理界面中,为3D设计提供了系统完善的解决方案。其中传统的die-by-die流程在3D结构建立后分别对两个die进行2D物理实现,同时工具也开发了多die协同(concurrent multidie)的物理实现流程,并行式进行多颗die的布局布线。此工作在实际项目中,使用Cadence Integrity 3D-IC工具,针对性地建立concurrent multidie的流程,将两颗die在同一个设计中实现并行摆放、3D结构单元(Hybrid Bonding bump)的位置优化、时钟树综合和绕线。协同优化的3D物理实现方案相比于die-bydie方案在设计整体结果上有更好的表现。 展开更多
关键词 Integrity 3D-IC 多芯片协同摆放 3DIC
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Risk factors of concurrent urinary sepsis in patients with diabetes mellitus comorbid with upper urinary tract calculi
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作者 Jian-Jie Gou Chao Zhang +1 位作者 Hai-Song Han Hong-Wei Wu 《World Journal of Diabetes》 SCIE 2023年第9期1403-1411,共9页
BACKGROUND Urinary sepsis is frequently seen in patients with diabetes mellitus(DM)complicated with upper urinary tract calculi(UUTCs).Currently,the known risk factors of urinary sepsis are not uniform.AIM To analyze ... BACKGROUND Urinary sepsis is frequently seen in patients with diabetes mellitus(DM)complicated with upper urinary tract calculi(UUTCs).Currently,the known risk factors of urinary sepsis are not uniform.AIM To analyze the risk factors of concurrent urinary sepsis in patients with DM complicated with UUTCs by logistic regression.METHODS We retrospectively analyzed 384 patients with DM complicated with UUTCs treated in People’s Hospital of Jincheng between February 2018 and May 2022.The patients were screened according to the inclusion and exclusion criteria,and 204 patients were enrolled.The patients were assigned to an occurrence group(n=78)and a nonoccurrence group(n=126).Logistic regression was adopted to analyze the risk factors for urinary sepsis,and a risk prediction model was established.RESULTS Gender,age,history of lumbago and abdominal pain,operation time,urine leukocytes(U-LEU)and urine glucose(U-GLU)were independent risk factors for patients with concurrent urinary sepsis(P<0.05).Risk score=0.794×gender+0.941×age+0.901×history of lumbago and abdominal pain-1.071×operation time+1.972×U-LEU+1.541×U-GLU.The occurrence group had notably higher risk scores than the nonoccurrence group(P<0.0001).The area under the curve of risk score for forecasting concurrent urinary sepsis in patients was 0.801,with specificity of 73.07%,sensitivity of 79.36%and Youden index of 52.44%.CONCLUSION Sex,age,history of lumbar and abdominal pain,operation time,ULEU and UGLU are independent risk factors for urogenic sepsis in diabetic patients with UUTC. 展开更多
关键词 Diabetes mellitus Upper urinary tract calculi Urinary sepsis Risk factors Risk prediction model Logistic regression concurrent urinary sepsis
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A Case Report of Concurrent Acne-Related Occurrence Complications: Telangiectasia, Post-Inflammatory Erythema, Post-Inflammatory Hyperpigmentation, and Atrophic and Hypertrophic Scars
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作者 Kanako Kita Ichiro Kurokawa 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第2期85-90,共6页
Prior to his initial diagnosis, a 21-year-old male had been experiencing facial acne for two years and had been treated by a doctor in private practice. The patient visited our department because the clinical manifest... Prior to his initial diagnosis, a 21-year-old male had been experiencing facial acne for two years and had been treated by a doctor in private practice. The patient visited our department because the clinical manifestations of mandibular acne did not improve. At the time of initial examination, telangiectasia (TE), post-inflammatory erythema (PIE), post-inflammatory hyperpigmentation (PIH), atrophic scars (ASs), and a hypertrophic scar (HS) with induration were observed on the right neck. We diagnosed this as an acne vulgaris complication. HS lesions were topically treated by injecting triamcinolone acetonide, and the patient was prescribed 8.1 g/day of oral Saireito (Japanese herb). Adapalene benzoyl peroxide gel and topical tacrolimus hydrate ointment were used to treat PIE and TE. Both HSs and PIE improved;however, TE and AS did not improve. Currently, the patient is under observation. We consider this to be a very rare concurrent occurrence of diverse complications of acne vulgaris, and present the following case study. 展开更多
关键词 Acne Vulgaris Acne-Related concurrent Occurrence Complications TELANGIECTASIA Atrophic Scar Hypertrophic Scar
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Dual-band multi-beam reconfigurable terahertz antenna based on graphene frequency selective surface
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作者 JIN Zhao RONG Yu +4 位作者 QIAO Li-Ping YU Jing-Dong WU Fei GUO Chen TIAN Dou 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第5期628-633,共6页
In this paper,a dual-band graphene-based frequency selective surface(GFSS)is investigated and the operating mechanism of this GFSS is analyzed.By adjusting the bias voltage to control the graphene chemical po-tential ... In this paper,a dual-band graphene-based frequency selective surface(GFSS)is investigated and the operating mechanism of this GFSS is analyzed.By adjusting the bias voltage to control the graphene chemical po-tential between 0 eV and 0.5 eV,the GFSS can achieve four working states:dual-band passband,high-pass lowimpedance,low-pass high-impedance,and band-stop.Based on this GFSS,a hexagonal radome on a broadband omnidirectional monopole antenna is proposed,which can achieve independent 360°six-beam omnidirectional scanning at 1.08 THz and 1.58 THz dual bands.In addition,while increasing the directionality,the peak gains of the dual bands reach 7.44 dBi and 6.67 dBi,respectively.This work provides a simple method for realizing multi-band terahertz multi-beam reconfigurable antennas. 展开更多
关键词 THz antenna MULTI-BEAM GRAPHENE dual-band RECONFIGURABLE
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基于k-体分划的D-concurrence多体纠缠测度
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作者 崔世杰 黄丽 +1 位作者 王银珠 马瑞芬 《太原科技大学学报》 2024年第1期109-112,共4页
对于有限维多体量子系统中的态,D-concurrence是一个重要的纠缠测度,在过去的十年中被深入探索。将D-concurrence的概念推广到k-体分划的多体量子系统,它可以度量多体量子态在k-体分划下的非经典纠缠性,并证明了纠缠测度的一些必要性质... 对于有限维多体量子系统中的态,D-concurrence是一个重要的纠缠测度,在过去的十年中被深入探索。将D-concurrence的概念推广到k-体分划的多体量子系统,它可以度量多体量子态在k-体分划下的非经典纠缠性,并证明了纠缠测度的一些必要性质,包括在k-可分态下纠缠测度为0,在局部酉操作下不变,在局部操作和经典通信(LOCC)下不增。 展开更多
关键词 D-concurrence 多体量子系统 k-体分划 量子纠缠测度
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一种基于Concurrent Apla语言的共享内存并发分布式算法2层验证方法 被引量:2
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作者 王昌晶 余小军 +2 位作者 沈德明 罗海梅 左正康 《江西师范大学学报(自然科学版)》 CAS 北大核心 2020年第3期301-306,共6页
形式化验证共享内存并发分布式算法已成为当前极具挑战性的问题之一,尤其是在云计算、多核、无线传感器网络、分布式数据库、区块链环境下.该文基于研究团队在形式化规约语言和方法、算法形式推导和验证方面的已有工作,以自定义泛型抽... 形式化验证共享内存并发分布式算法已成为当前极具挑战性的问题之一,尤其是在云计算、多核、无线传感器网络、分布式数据库、区块链环境下.该文基于研究团队在形式化规约语言和方法、算法形式推导和验证方面的已有工作,以自定义泛型抽象顺序设计语言Apla为基础,进一步研究并提出简明、高抽象用于并发分布式计算的Concurrent Apla语言,使其既支持顺序算法的验证又能有效地验证并发分布式算法.在依赖-卫式推理的基础上,提出一种新颖的2层并发分布式算法形式化验证方法,其中系统层用于处理并发级验证,而组件层用于处理顺序级验证.最后,通过2个实例验证了该方法的有效性和可行性. 展开更多
关键词 并发分布式计算 依赖-卫式推理 concurrent APLA 形式化验证
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COOPERATIVE DESIGN UNDER CONCURRENT ENGINEERING ENVIRONMENT 被引量:1
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作者 应维云 周儒荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期98-103,共6页
This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of en... This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of engineering design, especially conceptual design are reviewed. A deeper scientific analysis of intelligent design is discussed. A new problem solving strategy and methodologies to implement cooperative design are proposed. Finally, a conceptual model of a blackboard system for accomplishing conceptual design automation is presented. Its fundamental principles, system organization and key implementation techniques are investigated in detail. 展开更多
关键词 CAD artificial intelligence cooperative design concurrent engineering conceptual design
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Integrated Assembly Structure Design Within Concurrent Engineering
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作者 常向青 宁汝新 +2 位作者 姚珺 张旭 唐承统 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期306-311,共6页
Taking a microwave product as an example, a system of integrated assembly structure design is presented. Getting design constraints from the upstream design section through product data management(PDM), the system gen... Taking a microwave product as an example, a system of integrated assembly structure design is presented. Getting design constraints from the upstream design section through product data management(PDM), the system generates the assembly scheme using the case? based method, then assigns the design requirements into each component of the assembly. The detail design for each component can be performed under these design constraints. In order to practise concurrent design, the system sends the final design result to the upstream section and downstream section through PDM to achieve information sharing and integration. 展开更多
关键词 concurrent engineering assembly structure design case-based reasoning design constraints
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MODELING METHOD FOR CROSSCUTTING CONCERNS IN CONCURRENT SOFTWARE SYSTEM
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作者 苏旸 张敏情 +1 位作者 潘峰 陈平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期250-256,共7页
A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented(A-O) technique and the statechart of unified modeling language (UML). Modeled with UML statec... A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented(A-O) technique and the statechart of unified modeling language (UML). Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability. 展开更多
关键词 ASPECT-ORIENTED UML statechart concurrent software system crosscutting concern modular transition system
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Effect of concurrent precipitation on recrystallization textures in commercial Al-Mn alloys
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作者 涂益友 黄羚惠 +2 位作者 孙中岳 周雪峰 蒋建清 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期501-505,共5页
The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction(EBSD) analyses. A weak recrystallizati... The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction(EBSD) analyses. A weak recrystallization texture was observed in the AA 3003 alloy annealed at 783 K due to the high annealing temperature. Under the same conditions, extremely high P {011 } ( 111 ) recrystallization textures were detected in the AA 3003 alloy added with 0. 39% Sc. Based on the EBSD results, no intensely preferential orientation nucleation of recrystallization grains was observed in the early stage of recrystallizafion for both alloys. However, concurrent precipitation strongly retarded the growth of recrystallization grains, except for P nucleation sites, thereby conferring an apparent initial growth advantage for P nucleation sites compared with other nucleation sites. Therefore, a sharp P {011 } 〈 111 〉 texture appeared in concurrently precipitated AA 3003 alloys. 展开更多
关键词 AA3003 alloy concurrent precipitation recrystaUization texture
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QUANTITATIVE APPROACH TO REAL TIME STARTUP TIME DETERMINATION OF DOWNSTREAM PHASES IN CONCURRENT ENGINEERING
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作者 吕常魁 姜澄宇 王宁生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期206-212,共7页
Implementation of simultaneous execution phases in the concurrent engineering (CE) needs careful planning when the downstream phase could be activated as the upstream phase developed to a certain point. The determinat... Implementation of simultaneous execution phases in the concurrent engineering (CE) needs careful planning when the downstream phase could be activated as the upstream phase developed to a certain point. The determination of startup time of overlapping jobs in CE has long been a disturbance in manufacturing industry implementing CE programs. A novel model based on both fuzzy logic and neural network is proposed to mathematically formulate the inter-connective information between the two coupled phases in CE projects, and to determine the startup time of downstream phases in real time. The information transferring between the two coupled phases is quantified by using the negative Shannon entropy. Based on this algorithm, a PDM-based framework is proposed to narrow the gap between pro-duct design and manufacture, in which five modules are built to monitor, reshuffle and implement the simultaneous executing processes. Finally, an example is given to illustrate applications of the algorithm in the real world. 展开更多
关键词 concurrent engineering negative entropy multilayer principle decision-making matrix
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