Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-12-28 Cooperative journals: 《中国全科医学》
Abstract： Background The modified COVID-19 Yorkshire Rehabilitation Scale（C19-YRSm） has been shown to be useful to assess and monitor patients in post-COVID-19 syndrome in developed countries. However，its reliability and validity in the Chinese population remains unclear. Objective To translate the C19-YRSm into a Chinese version（C19-YRSm-C），and test the reliability and validity of the Chinese version. Methods After obtaining the approval of the translation and use authority of the C19-YRSm from MANOJ SIVAN's team at the University of Leeds，United Kingdom，the research team translated the C19-YRSm and formed the C19-YRSm-C after translation，back-translation，and cross-cultural adaptation，according to the Translation and Cross-cultural Adaptation Procedure. From May 1 to 7，2023，a simple random sampling method was used to select post COVID-19 patients from the "Wen Juan Xing" platform sample pool as the study subjects. The General Information Questionnaire and the C19-YRSm-C were used to survey them. 13 experts were invited to evaluate the content validity of the scale. The C19-YRSm-C was subjected to item analysis，reliability and validity analysis. Results A total of 512 questionnaires were distributed and 370 valid questionnaires were recovered，with a valid recovery rate of 72.3%. The results of item analysis showed that the CR values of the items ranged from 6.589 to 22.725（P<0.001），and the item-total correlation coefficients of the scale ranged from 0.547 to 0.806 （P<0.001）. For reliability，the Cronbach's α coefficient，Guttman Split half coefficient and test-retest reliability of the C19-YRSm-C was 0.881，0.837 and 0.816，respectively. For content validity，the item-level content validity index（I-CVI） of the C19-YRSm-C ranged from 0.692 to 1.000，and the scale-level validity index（S-CVI） was 0.914. The results of confirmatory factor analysis（CFA） showed that the fitting indicators of the initial model were undesirable. After the establishment of a covariance correlation between error variables e12 and e13 according to the indication prompts，the fitting indicators of the modified model were within the acceptable range except for the adjusted goodness of-fit index （AGFI）. The results of discriminant validity analysis showed that the differences in scores for the 4 subscales of the C19-YRSm-C among post-COVID-19 patients with different chronic disease history and cumulative number of COVID-19 showed statistically significant differences（P<0.05）. The differences were statistically significant when comparing the scores of the 3 subscales in addition to other symptoms before and after COVID-19 infection（P<0.05）. Conclusion The C19-YRSm-C has good reliability and validity，with good applicability in Chinese population，which can be used to assess and monitor the rehabilitation status of post COVID-19 patients in China.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-09-21
Abstract： The local chronicle is an important material that reflects the history, society and economy of a place. Taking the "Yinna Mountain Annals" compiled by Li Shichun of the Ming Dynasty, which was collated by Zhongdong as a study sample, through literature analysis and data statistical analysis, it was found that the tourist groups included in the mountain annals were mainly literati and gentry, including four types: in-service officials, retired officials, knowledge groups with achievements, and knowledge groups without achievements. Tourists mainly generated from the regions around Meizhou and Chaoshan ,then from other regions in Guangdong Province such as Guangzhou and Huizhou, as well as from neighboring provinces such as Jiangxi and Fujian. The tourist generating areas were highly consistent with the influence coverage of Yinna Mountain, just as the old saying goes, "well-known to Chaozhou and Meizhou , and famous in Fujian and Guangdong". Due to the limitations of transportation conditions in the era, tourists often used a combination of water and land transportation, Therefore, the generating areas of tourists were always along water transportation routes. Tourists' travel was mainly based on five reasons: scenic exploration, official visits, invitations from family and friends, visits along the way, and religious worship. In addition, tourist’s consumption of food, accommodation, transportation, and travel in ancient Yinna Mountain showed strong characteristics of the times, regions, and literati.
Peer Review Status:
Awaiting Review
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-07-05 Cooperative journals: 《中国全科医学》
Abstract： Background The clinical application of flash glucose monitoring system（FGM）is becoming increasingly widespread，which can be continuously monitored for 14 days and does not require fingertip blood correction during wearing，providing a basis for clinical treatment. Therefore，the accuracy of FGM is particularly important. Objective To investigate the effect of human body composition and serum biochemical indicators on the accuracy of FGM sensor. Methods Patients with type 2 diabetes mellitus（T2DM）hospitalized in the department of endocrinology of the Second Affiliated Hospital of Zhengzhou University in 2022 were selected as the study objects，and their general data were collected through the electronic medical record system. The blood glucose were detected by FGM and compared with intravenous blood glucose，the physical analysis data of patients was collected. Fasting venous blood was collected to analyze hematological parameters. The clinical accuracy of FGM was evaluated by Clarke error grid analysis. The included patients were divided into the accurate group（MARD<10%，n=23）and inaccurate group（MARD>20%，n=34）according to the matched mean absolute relative difference of blood glucose （MARD）. Binary Logistic regression was used to analyze the influencing factors of FGM accuracy. Results A total of 694 pairs of blood glucose data of 154 patients were collected. Clarke error grid analysis was performed on the blood glucose values of FGM scans using venous blood glucose as the reference value. The results showed that 82.9% fell in zone A，16.9% fell in zone B，99.8% fell in zone A+B，and 0.2% fell in zone D，with an average MARD of 12.7%. MARD and muscle mass in the inaccurate group were higher than those in the accurate group（P<0.05），while uric acid，body fat mass and fat percentage were lower than those in the accurate group（P<0.05）. Uric acid，body fat mass and fat percentage of male patients in the inaccurate group were lower than those in the accurate group，while the MARD value and muscle mass of male patients were higher than those in the accurate group（P<0.05）. MARD value of female patients in the inaccurate group was higher than that in the accurate group （P<0.05）. Binary Logistic regression analysis showed that muscle mass and blood uric acid concentration were influencing factors of the accuracy of FGM（P<0.05）. Conclusion The overall accuracy of FGM sensor meets the international standards. The accuracy of FGM sensor is related to uric acid level and muscle mass，but it was not affected by electrolyte ions in blood and other biochemical indicators，and interfered by human moisture，fat mass，inorganic salt content，fat thickness of the sensor wearing site and other factors.
Subjects: Nursing >> Nursing submitted time 2023-04-24
Abstract： This review summarized the current status of domestic and international research on epidemiology, evaluation, treatment and nursing interventions for elderly female urinary incontinent patients. This review would also provide a theoretical basis for further developing to build up total quality management system in elderly female urinary incontinent patients.
Peer Review Status:Awaiting Review
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-04-03 Cooperative journals: 《中国全科医学》
Abstract： Background IgA nephropathy（IgAN）is a chronic inflammatory illness involving multiple factors and genes，platelet-albumin ratio（PAR） is regarded as a novel marker of inflammation，but the connection between PAR and IgA nephropathy remains unclear. Objective To examine the correlation of PAR with the clinicopathological indicators of IgAN and to evaluate the clinical significance of PAR in IgAN. Methods From October 2019 to August 2020，210 patients with IgAN diagnosed by percutaneous renal biopsy at the Department of Nephrology of the First Affiliated Hospital of Kunming Medical University were selected as study subjects，general inforamtion of the included patients（gender，age，systolic blood pressure，diastolic blood pressure and disease duration），laboratory indicators〔white blood cell（WBC），absolute neutrophil count （ANC），absolute lymphocyte count（ALC），absolute monocyte count（AMC），platelet count（PLT），serum albumin （ALB），serum uric acid（SUA），blood urea nitrogen（BUN），serum creatinine（Scr），immunoglobulin A（IgA），immunoglobulin M（IgM），immunoglobulin G（IgG），serum complement C3，serum complement C4，urine red blood cell count（URBC），24 h urinary microalbumin（24 h mALB），24 h micrototal protein（24 h MTP）〕，percutaneous renal biopsy pathology results，calculated neutrophil-to-lymphocyte ratio （NLR），platelet-to-lymphocyte ratio （PLR），PAR，immunoglobulin A-to-complement C3 ratio （IgA/C3），immunoglobulin G-to-complement C3 ratio （IgG/C3），complement C3-to-complement C4 ratio （C3/C4），and estimated glomerular filtration rate（eGFR）. The study subjects were divided into three groups：group Q1（PAR ≤ 5.626 5），group Q2（5.6265 ﹤ PAR ≤ 6.984 3）and group Q3（PAR ≥ 6.984 3）.The differences in the baseline inforamtion among the three groups were compared，Spearman correlation analysis and Logistic regression analysis were used to explore the correlation between PAR and IgAN clinicopathological indicators of IgAN，receiver operating characteristic（ROC）curves were plotted to analyze the predictive value of PAR on pathological indicators. Results There were significant differences in gender，WBC，ANC，PLT，PLR，PAR，URBC，ALB，IgG/C3，24h-mALB， 24h-MTP，M lesions，Lee classification among the three groups（ P<0.05）. Spearman correlation analysis showed that PAR was positively correlated with PLT，WBC，ANC，PLR，URBC，24 h-mALB，24 h-MTP，M lesions，E lesionsand Lee classification，and negatively correlated with ALB and IgG/C3（ P<0.05）. Multivariate Logistic regression analysis showed that PAR〔 OR=2.688，95%CI（1.178，6.135）〕 and ALB〔 OR=0.736，95%CI（0.587，0.923）〕 were independent influencing factors for M1 lesions in IgAN patients（ P<0.05），ALB〔 OR=0.896，95%CI（0.824，0.973）〕 was an independent influencing factor for E1 lesions（ P<0.05）. The ROC curve showed that area-under-curve（AUC） of PAR predicting M1 and E1 lesions in IgAN patients was 0.727 and 0.599，respectively. Conclusion PAR was significantly correlated with the clinical manifestations and the degree of M and E lesions of IgAN，which has clinical significance in evaluating IgAN activity. Patients with high PAR levels should be treated more aggressively to inhibit active lesions and improve renal outcomes.
Subjects: Mechanics >> Applied Mechanics submitted time 2023-03-20 Cooperative journals: 《应用力学学报》
Abstract： The high-level rocket lift-off noise induced by the hypersonic jet has adverse impacts on thestructural security and equipment reliability of the rocket ;therefore , it is of great significance to make theprediction and reduction of high-speed jet noise environment. A numerical analysis method based on de-tached eddy simulation ( DES) turbulence model and combined transport equation, discrete phase model(DPM) and FW-H equation was established to calculate the noise of multi-components rocket jet and wa-ter considering evaporation inserts multi-components high speed jet. The prediction pf hypersonic jet flowcondition and noise environment of liquid rocket engine was completed.'The results show that the eror be-tween the predicted results and experimental results of overall sound pressure level of probes is within�3 dB.Furthermore , the annular water inserts noise reduction system was designed , the noise reductionlaw of water involved in high Mach number jet , considering evaporation effect and influence of complex deflector duct configuration , was studied , which reveals that shearing effect , momentum transfer and evapora-tion are important incentives for noise reduction.Besides , the noise suppression effect increases monoton-ously with the increase of mass flow rate , and increases first and then decreases with the increase of inter-vention angle.This study is of great importance in design and engineering of the water inserts system.
Subjects: Mechanics >> Applied Mechanics submitted time 2023-03-20 Cooperative journals: 《应用力学学报》
Abstract： Based on the experimental results of the parameters related to the energy expenditure of back-pack weight-bearing walking, this paper establishes a mathematical model to calculate energy consump-tion , verifies the correctness of its model , and discusses the effect of backpack weight-bearing parameterson the energy expenditure of human walking. A dual-mass-spring model ,similar to the human body back-pack weight-bearing walking model , was used to construct the model kinematic equation.Results show thatwhen the natural frequency of elastic backpack is lower than the walking resonance frequency , energy ex-penditure is significantly reduced.The energy expenditure of the elastic backpack increases near the reso-nance frequency of the human body and is more significant at a higher speed or greater weight-bearing.The calculated results of the net mechanical work model of the vertical displacement ,phase dfference anddifferent backpack parameters of the human body are basically consistent with the experimental results. Appropriate elastic backpack can effectively reduce energy expenditure during damping , heavy load andrapid walking.'The calculation of backpack weight-bearing walking energy consumption by double mass-spring model is basically consistent with the experimental results, indicating that the modelig method ofthis model is reasonable and can be used to predict energy expenditure of human body backpack weight-bearing walking.
Subjects: Biology >> Botany submitted time 2022-10-27 Cooperative journals: 《广西植物》
Abstract： To study the constituents of (Isodon macrocalyx), thirteen diterpenoids were isolated from the aerial parts of I. macrocalyx by means of various column chromatographic techniques, including silica gel, ODS, Sephadex LH-20 and RP C18 pre-HPLC. The structures of the isolated diterpenoids were determined on the basis of analyses of spectroscopic methods (1H and 13C-NMR spectroscopy), high-resolution electrospray ionization mass spectrometry (HRESIMS), and comparison of their spectroscopic data with previously reported data. The results showed that the diterpenoids were identified as 19-hydroxytotarol (1), macrophynin E (2), inumakoic acid (3), inumakiol D (4), 4β-carboxy-19-nortotarol (5), (-)-lambertic acid (6), 2-oxo-5-fagonene (7), isodoterniofiln B (8), longikaurin E (9), longikaurin A (10), rabdotemin H (11), 16S-dihydr olongikaurin A (12), and ent-3S,16S,17-trihydroxy-kauran-2-one (13). All diterpenoids were isolated from I. macrocalyx for the first time.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2022-05-10 Cooperative journals: 《计算机应用研究》
Abstract： The drawbacks of existing task recommendation in mobile crowd sensing were as follows: on the one hand, not fully considering the influence of spatial-temporal information on worker preference led to low accuracy of recommendation; On the other hand, ignoring the impact of task popularity on recommendation led to poor recommendation coverage. To solve these drawbacks, this paper proposed a novel task recommendation approach based on spatial-temporal information and task popularity analysis in mobile crowd sensing. Firstly, this approach made full use of the relevant information contained in the worker execution record (e. g. , the time and location of worker performing tasks) to accurately predict the preference of worker for performing tasks. Secondly, in order to reduce the impact of popular tasks on recommendation coverage, this paper analyzed task popularity based on worker reputation and task execution record, and designed appropriate task popularity penalty factor. Then, combining worker preference and task popularity penalty factor, this paper provided an appropriate task recommendation list for each worker. Finally, the experimental results show that compared with the existing baseline methods, the proposed method improves the recommendation accuracy by 3.5% and the recommendation coverage by 25%.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-03-30 Cooperative journals: 《广西植物》
Abstract： To study the chemical constituents from the n-BuOH part of the bark of Streblus ilicifolius, sixteen compounds were isolated and purified from the n-BuOH part of the bark of S. ilicifolius by means of various column chromatographic techniques, including silica gel, ODS, Sephadex LH-20 and preparative RP-HPLC. The structures of the isolates were identified by physiochemical properties and spectral data. The results were as follow: The compounds were identified as icariside E5 (1), secoisolariciresinol 9-O-β-glucopyranoside (2), 2,4,6-trimethoxyphenol-1-O-β-D-glycoside(3),9-O-β-glucopyranosyl trans-cinnamyl alcohol(4), 3,4,5-trimethoxyphenyl-1-O-β-apiofuranosyl-(1"→6´)-β-glucopyranoside(5),3-hydroxy-4,5-dimethoxyphenyl-β-D-glucopyranoside(6), 2,6-dimethoxy-4- hydroxyphenol-1-O-β-D-glucopyranoside (7), isotachioside(8), ficuscarpanoside A(9), uridine(10), methyl syringate 4-O-β-D-glucopyranoside (11), 3,4,5-trimethoxyphenyl-β-D-glucopyranoside(12), luteolin(13), ginsenoside Rg1(14), (+)-lyonirenisol-3α-O-β-D-glucopyranoside (15), myricetin 3-neohesperidoside (16). All compounds were isolated from plants of Streblus for the first time.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2019-01-03 Cooperative journals: 《计算机应用研究》
Abstract： In the application scenario of edge computing, resource deployment and allocation are important issues. In order to address the load balancing needs in edge computing network, this paper propose a scheduling scheme based on centralized control. This scheme decides which nodes to deploy edge computing module firstly, then considering users’ data and requests, minimizes the average end-to-end delay of traffic through scheduling while meeting the load balancing constraints. The evaluation results indicate that the number of edge computing nodes and the load balancing level of computing and network resources may affect the average end-to-end delay of traffic. Selecting a small number of suitable nodes as edge computing nodes and making the load balancing level of computing and network resources appropriate can effectively reduce the average end-to-end delay.
Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究高温热处理粉料对蛋鸡生产性能、蛋品质及鸡蛋卫生指标的影响。选取40周龄的海兰褐蛋鸡1 080只，随机分为4组，每组6个重复，每个重复45只鸡。对照组饲喂普通粉状蛋鸡料，试验组分别饲喂经70、80和90 ℃ 3种调质温度处理的粉状蛋鸡料。预试期1周，正试期12周。结果表明：1）试验组粉料的细菌总数和大肠菌群数量均显著低于对照组（P0.05）。2）各组之间第1～12周蛋鸡生产性能指标的差异不显著（P>0.05）。3）各组之间第12周蛋壳强度、蛋壳厚度、蛋形指数、蛋黄比率和哈氏单位的差异不显著（P>0.05），80 ℃高温热处理粉料组蛋黄的亮度、红度和黄度值显著高于对照组（P0.05），蛋壳表面的大肠菌群数量均小于对照组。5）试验组的肌胃、空肠和回肠相对重量小于对照组，但差异不显著（P>0.05）；随着调质温度的升高，试验组腺胃、肌胃、十二指肠、空肠和回肠的相对重量都逐渐增大，但差异不显著（P>0.05）。结果提示，高温热处理可以改善饲料和鸡蛋的卫生指标，但对蛋鸡生产性能、蛋品质和消化道指标的影响不显著。
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究不同饲料加工工艺及维生素添加量对肉仔鸡生长性能和屠宰性能的影响。试验选用480只1日龄体重接近的白羽爱拔益加肉仔鸡，随机分为4组，每组8个重复，每个重复20只鸡。对照组（A组）饲粮采用普通饲料加工工艺，配方中添加正常剂量的复合维生素[前期（1~21日龄）350 mg/kg、后期（22~42日龄）250 mg/kg]；试验组饲粮采用高效调质低温制粒工艺，减少配方中复合维生素添加量（B组：前期280 mg/kg、后期200 mg/kg；C组：前期224 mg/kg、后期160 mg/kg；D组：前期180 mg/kg、后期128 mg/kg）。试验期42 d。结果表明：试验前期，A组肉仔鸡饲料淀粉糊化度显著低于B组、C组和D组（P＜0.05）。试验后期，A组肉仔鸡饲料颗粒耐久性指数显著低于B组、C组和D组（P＜0.05）。试验前期、后期和全期（1~42日龄），各组肉仔鸡的末重、平均日增重、平均日采食量和料重比均差异不显著（P＞0.05）。各组肉仔鸡的腿重/屠宰重、胸肉重/屠宰重、心脏重/屠宰重、肝脏重/屠宰重、脾脏重/屠宰重、肌胃重/屠宰重、腺胃重/屠宰重均差异不显著（P＞0.05），各组十二指肠、空肠和回肠的长度及重量均差异不显著（P＞0.05）。由此可见，肉仔鸡饲粮采用高效调质低温制粒工艺，颗粒饲料加工质量优于普通饲料加工工艺，且饲料配方中减少维生素添加量对肉仔鸡生长性能和屠宰性能与普通饲料加工工艺无显著差异，即该工艺可节约维生素使用量。
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究在同一配方条件下，不同玉米粉碎粒度对蛋鸡生产性能、蛋品质及消化机能影响。饲料原料使用锤片式粉碎机进行粉碎，其中玉米分别用4.0、5.0、6.0、7.0、8.0和10.0 mm的筛孔直径进行粉碎，其他饲料原料均采用5.0 mm的筛孔直径进行粉碎。选取210日龄的海兰褐蛋鸡2 592只，随机分为6组，每组6个重复，每个重复72只，各组蛋鸡分别饲喂不同玉米粉碎粒度的饲粮。试验期为16周。结果表明：1）玉米和全价饲粮的几何平均粒径随着筛孔直径的增大而增大，但全价饲粮的差异较小。随着筛孔直径的逐渐增大，粉碎能耗逐渐下降，从3.93 kWh/t降低到1.19 kWh/t。2）随着玉米粉碎粒度的增大，平均蛋重呈先升高后降低的趋势，5.0 mm筛孔直径组平均蛋重显著高于10.0 mm筛孔直径组（P＜0.05）。随着玉米粉碎粒度的增大，破蛋率、软蛋率呈先降低后升高的趋势，6.0 mm筛孔直径组破蛋率显著低于10.0 mm筛孔直径组（P＜0.05），7.0 mm筛孔直径组软蛋率显著低于4.0 mm筛孔直径组（P＜0.05）。3）7.0 mm筛孔直径组蛋黄比率显著大于5.0 mm筛孔直径组（P＜0.05）。4）5.0 mm筛孔直径组粗蛋白质的表观消化率显著高于6.0、7.0、8.0、10.0 mm筛孔直径组（P＜0.05），5.0 mm筛孔直径组总能的表观消化率显著高于4.0、7.0、10.0 mm筛孔直径组（P＜0.05），7.0 mm筛孔直径组干物质的表观消化率显著高于4.0、10.0 mm筛孔直径组（P＜0.05）。5）7.0 mm筛孔直径组盲肠大肠杆菌的数量显著低于4.0、10.0 mm筛孔直径组（P＜0.05），5.0 mm筛孔直径组的空肠指数显著高于6.0、7.0和8.0 mm筛孔直径组（P＜0.05），8.0 mm筛孔直径组腺胃食糜的pH显著低于4.0、5.0 mm筛孔直径组（P＜0.05），6.0 mm筛孔直径组回肠食糜pH显著高于4.0、5.0、7.0、10.0 mm筛孔直径组（P＜0.05）。由此可见，针对蛋鸡饲粮，粉碎玉米筛孔直径为6.0 mm时，蛋鸡的生产性能和蛋品质较佳，并有利于肠道健康。
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究玉米粉碎粒度与破碎粒度对蛋鸡生产性能、蛋品质和消化器官指数的影响。对照组饲粮中玉米采用锤片粉碎机进行粉碎，筛片孔径分别为4.0和8.0 mm，试验组饲粮中玉米采用对辊式滚刀粉碎机进行破碎，碟盘间隙分别为0.3、0.7、1.1和1.5 mm。选取30周龄的海兰褐蛋鸡1 620只，随机分为6组，每组6个重复，每个重复45只鸡，进行养殖试验，试验期8周。结果表明：玉米的几何平均粒径随着粉碎机筛片孔径或碟盘间隙的增大而显著增大（P0.05）；采用对辊式滚刀粉碎机破碎后，碟盘间隙0.7 mm组（几何平均粒径1 446.30 μm）蛋鸡生产性能优于其他各组，且产蛋率显著高于筛片孔径8.0 mm组（P0.05）。结果显示，针对蛋鸡饲料，玉米采用对辊式滚刀粉碎机破碎优于锤片粉碎机粉碎，碟盘间隙0.7 mm（几何平均粒径1 446.30 μm）时，蛋鸡生产性能、蛋品质和消化器官指数最佳。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-05-24 Cooperative journals: 《计算机应用研究》
Abstract： Packet-level caching is difficult to implement in the traditional caching system. The emergence of Information-centric networking has alleviated this problem. However, the packet-level caching is still facing severe scalability issues. This paper analyzed the issues which limit the implementation of packet-level caching and proposed a packet-level caching optimization approach. This scheme reduces the consumption of fast memory by creating the index with group prefixes instead of the packet prefixes, while the group-level popularity is also used to optimize caching decision. This paper evaluated the performance of the scheme through extensive simulation experiments regarding a wide range of performance metrics. The experimental results indicate the scheme can reduce the fast memory usage and achieve significant improvement in terms of server load reduction ratio, average hop reduction ratio and average cache hit ratio, compared with current packet-level caching schemes.
Subjects: Dynamic and Electric Engineering >> Engineering Thermophysics submitted time 2017-11-07 Cooperative journals: 《工程热物理学报》
Abstract：建立了流量分配不均下多股流板翅式换热器通用传热数学模型，并通过FLUENT仿真和自主编程相结合的方式实现了板翅式换热器数值计算。以机载交叉式三股流板翅式换热器为例，通过与文献试验数据对比论证了数值方法的合理性，分析了变流体比热容、流体入口温度和流体流动阻力条件下流量分配不均对多股流板翅式换热器传热性能的影响。
Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《金属学报》
Abstract：采用真空感应炉制备316L-50Mn初始合金，然后通过真空环境下Mn升华去合金制备多孔不锈钢，应用SEM、EDS和XRD等对物理真空去合金工艺方法制备的多孔不锈钢进行分析，并研究去合金过程中温度以及时间对孔的形成、发展以及孔的形貌的影响。结果表明，物理真空去合金工艺可以制备多孔不锈钢，其孔隙率为30%~60%，孔径为0.5~3 μm，多孔层深度达到15~55 μm。真空热处理温度和时间是物理真空去合金制备方法的2个关键因素，处理温度主要通过影响Mn元素挥发和体扩散速率进而影响孔的形貌，而处理时间对多孔层的深度起到主要作用。
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-15 Cooperative journals: 《金属学报》
Abstract：通过分级淬火方法测定了7050铝合金模锻件的TTT曲线，利用TEM和JMA方程等分析手段研究了固溶-等温淬火-时效过程中微观组织的演变和相变动力学规律。结果表明：合金TTT曲线的鼻尖温度在330℃附近，淬火敏感区间为270-400℃，淬火敏感性为：中温>低温>高温；等温保温过程中过饱和固溶体主要析出以Al3Zr粒子为形核核心的 平衡相，在鼻尖温度下随保温时间延长析出相体积分数快速增加，同时晶界变得连续而粗化、PFZ宽化，在远离鼻尖的温度下保温合金析出速率减慢，晶界连续化和粗化程度降低；在210-450℃温度下保温合金析出相形态以片层状和针状共存，拟合S曲线的n值在0.5-0.65的范围内，解释了不同温度下保温合金以片层状相析出为主、针状相析出为辅的析出机理。
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