volume

摘要： BACKGROUND Branch duct-intraductal papillary mucinous neoplasms(BD-IPMNs)are the most common pancreatic cystic tumours and have a low risk of malignant transformation.Current guidelines only evaluate cyst diameter as an important risk factor but it is not always easy to measure,especially when comparing different methods.On the other side,cyst volume is a new parameter with low interobserver variability and is highly reproducible over time.AIM To assess both diameter and volume growth rate of BD-IPMNs and evaluate their correlation with the development of malignant characteristics.METHODS Computed tomography scans and magnetic resonance imaging exams were retrospectively reviewed.The diameter was measured on three planes,while the volume was calculated by segmentation:The volume of the entire cyst was determined by manually drawing a region of interest along the edge of the neoplasm on each consecutive slice covering the whole lesion;therefore,a threedimensional volume of interest was finally obtained with the calculated value expressed in cm^(3).Changes in size over time were measured.The development of worrisome features was evaluated.RESULTS We evaluated exams of 98 patients across a 40.5-mo median follow-up time.Ten patients developed worrisome features.Cysts at baseline were significantly larger in patients who developed worrisome features(diameters P=0.0035,P=0.00652,P=0.00424;volume P=0.00222).Volume growth rate was significantly higher in patients who developed worrisome features(1.12 cm^(3)/year vs 0 cm^(3)/year,P=0.0001);diameter growth rate was higher as well,but the difference did not always reach statistical significance.Volume but not diameter growth rate in the first year of follow-up was higher in patients who developed worrisome features(0.46 cm^(3)/year vs 0 cm^(3)/year,P=0.00634).CONCLUSION The measurement of baseline volume and its variation over time is a reliable tool for the follow-up of BD-IPMNs.Volume measurement could be a better tool than diameter measurement to predict the development of worrisome features.

摘要： Antarctic Bottom Water(AABW)plays an important role in the meridional overturning circulation and contributes significantly to global heat transport and sea level rise(SLR).Based on the Global Ocean(1/12)°Physical Reanalysis(GLORYS12V1)products and conductivity-temperature-depth instrument data from the World Ocean Circulation Experiment hydrographic program,we analyzed the trends in the thickness,volume,temperature,salinity,and neutral density of the AABW in the Amundsen Sea from 1993 to 2017.Over the past 25 years,the volume has decreased by 3.45×10^(12) m^(3)/a,thinning at a rate of 5 m/a.In the vertical direction,the contraction of the AABW is compensated by the volume expansion of the Circumpolar Deep Water.As the volume of AABW decreases,the temperature of the AABW increases by about 0.002°C/a.This warming is equivalent to a heat flux of 0.27 W/m^(2).A local SLR is produced due to thermal expansion of 0.35 mm/a.During the study period,the neutral density decreased by 0.0003 kg/(m^(3)·a)due to warming.In the horizontal direction,the volume of AABW flowing from the Ross Sea into the Amundsen Sea gradually decreases and the temperature of the AABW increases continuously.The horizontal transport loss of the AABW volume is 4.07×10^(14) m^(3) and the horizontal heat transport results in a 0.03°C increase in the temperature of the AABW.

摘要： BACKGROUND The prevalence of depression in patients with chronic obstructive pulmonary disease(COPD)ranges from 10%to 42%,but the diagnosis of depression in patients with COPD is often unrecognized and untreated.Unrecognized depression has major implications for compliance with medical treatment,prolonged lengths of stay,increased frequency of hospital admissions,and increased consultations with primary care physicians.Many studies have attempted to identify risk factors for progression,prognosis and response to therapy in patients with depression.However,few studies have examined the risk factors for depression in patients with COPD,and some results remain controversial.AIM To identify the potential risk factors to define patients with COPD who are at“high risk”of depression.METHODS The clinical data of 293 patients with COPD were reviewed from January 2017 to December 2018.The correlations between demographics,clinical characteristics and depression were analyzed.The risk factors for depression in patients with COPD were identified by multivariate logistic regression analysis.The cutoff value,sensitivity and specificity of the independent correlation factors were calculated with a receiver operating characteristic curve.RESULTS Of the 293 patients included,65(22.18%)individuals were identified to have depression.Significant differences were detected between patients with and without depression in terms of body mass index(BMI),forced expiratory volume in 1 s(FEV1),and COPD assessment test(CAT)score(all P<0.05).Low BMI,low FEV1,and high CAT were independent risk factors for depression in patients with COPD and the cutoff values of BMI,FEV1,and CAT scores were 21.373 kg/m2,0.855 L and 12.5,respectively.CONCLUSION Low BMI,low FEV1,and high CAT score were identified as independent risk factors for depression in patients with COPD.

摘要： Objective:To investigate the effect of prostate volume on robot-assisted radical prostatectomy.Methods:Clinical data of 75 patients underwent RARP in the Affiliated Hospital of Qingdao University were retrospectively analyzed.The patients were divided into 3 groups according to size of prostate.A total of 35 cases with prostate volume less than 30ml were recorded as group 1,27 cases with volume of 30 to 50 ml were recorded as group 2,and 13 cases with volume greater than 50ml were recorded as group 3.Age,BMI,preoperative PSA,operation time,intraoperative bleeding volume,postoperative drainage volume,indwelling time of catheter,indwelling time of drainage tube,total hospitalization time,pathological stage,surgical margin,urine control and biochemical recurrence were observed.Results:All operations were performed under Da Vinci robot assistance,and no patient was transferred to open surgery.There was no significant difference in age,preoperative PSA,BMI,operation time,intraoperative bleeding volume,postoperative drainage volume,indwelling time of catheter,total hospitalization time,pathological stage,rate of positive surgical margin and recovery of urinary continence between the groups.Indwelling time of drainage tube was longer in group with larger prostate,6.4(±4.5)days in group 1,6.3(±2.9)days in group 2 and 7.1(±2.5)days in group 3.Gleason score was lower in group with larger prostate,with statistical difference.Conclusion:Prostate volume had no significant effect on urinary control,rate of positive surgical margin and recurrence after RARP.Gleason score of pathological tissue was lower and indwelling time of drainage tube was longer in patients with larger prostate after RARP.Operation time and intraoperative bleeding volume of large prostate patients underwent RARP need to be further studied.RARP has certain advantages for patients with large prostate.

摘要： Exploration and exploitation for hydrocarbon are associated with a lot of complexities, it is therefore necessary to integrate available geologic models for accurate hydrocarbon prospecting and risk analysis. This study is aimed at determining the structural, petrophysical and volumetric parameters for reservoir evaluation within the Rancho field. 3D seismic data was used for evaluating the hydrocarbon potential of the field. A suite of well logs but not limited to gamma ray logs (GR), deep resistivity log (DRES), neutron log (NPHI) and density log (RHOB) from four (4) wells were employed in characterising dynamic properties of the reservoirs. The GR log was used in lithology identification while the resistivity log was used in identifying probable hydrocarbon bearing sands. A correlation exercise was carried out to identify lateral continuity and discontinuity of facies across the wells. Thereafter petrophysical parameters were analysed from the suite of wire line logs. Major faults were mapped on the 3D seismic data and identified hydrocarbon bearing sand tops from the well logs were mapped as horizons on the seismic section, maps were generated and volumetric analysis was done. Nine (9) hydrocarbon sands (Sands A - I) were identified within the study area. The well log revealed an alternation of sand and shale layers as well as shale layers increased in thickness with depth, while the sand bodies reduced in thickness with depth which characterized the Abgada Formation of the Niger Delta. The effective porosities of the sands range from 21% - 31%, the permeability ranges from 28% - 44%, 70% - 80% for the net to gross, volume of shale range from 14% - 40% and hydrocarbon saturation ranges from 63% - 82%. Twelve (12) faults were mapped within the study area and the structural styles revealed a fault assisted closures. The volumetric analysis showed that Sand F had Stock Tank Oil Initially In Place (STOIIP) of 5,050,000,000 bbls of oil and Sand G had STOIIP of 17,870,000,000 bbls, these sands are proposed to be developd because of the volume of oil in them and area covered by the reservoir, calculated Gross Rock Volume (GRV) of 29.5 km3 and 104.5 km3 respectively.

摘要： The present study is to improve the volume flow rate of an axial fan through optimizing the blade shape under the demand for a specified static pressure. Fourteen design variables were selected to control the blade camber lines and the stacking line and the values of these variables were determined by using the experimental design method of the Latin Hypercube Sampling (LHS) to generate forty designs. The optimization was carried out using the genetic algorithm (GA) coupled with the artificial neural network (ANN) to increase the volume flow rate of the axial fan under the constraint of a specific motor power and a required static pressure. Differences in the aerodynamic performance and the flow characteristics between the original model and the optimal model were analyzed in detail. The results showed that the volume flow rate of the optimal model increased by 33%. The chord length, the installation angle and the cascade turning angle changed considerably. The forward leaned blade was beneficial to improve the volume flow rate of the axial fan. The axial velocity distribution and the static pressure distribution on the blade surface were improved after optimization.

摘要： BACKGROUND Liver resection has become safer as it has become less invasive.However,the minimum residual liver volume(RLV)required to maintain homeostasis is unclear.Furthermore,the formulae used to calculate standard liver volume(SLV)are complex.AIM To review previously reported SLV formulae and the methods used to evaluate the minimum RLV,and explore the association between liver volume and mortality.METHODS A systematic review of Medline,PubMed,and grey literature was performed.References in the retrieved articles were cross-checked manually to obtain further studies.The last search was conducted on January 20,2019.We developed an SLV formula using data for 86 consecutive patients who underwent hepatectomy at our institution between July 2009 and August 2011.RESULTS Linear regression analysis revealed the following formula:SLV(mL)=822.7×body surface area(BSA)?183.2(R2=0.419 and R=0.644,P<0.001).We retrieved 25 studies relating to SLV formulae and 12 studies about the RLV required for safe liver resection.Although the previously reported formulae included various coefficient and constant values,a simplified version of the SLV,the common SLV(cSLV),can be calculated as follows:cSLV(mL)=710 or 770×BSA.The minimum RLV for normal and damaged livers ranged from 20%-40%and 30%-50%,respectively.The Sapporo score indicated that the minimum RLV ranges from 35%-95%depending on liver function.CONCLUSION We reviewed SLV formulae and the minimum RLV required for safe liver resection.The Sapporo score is the only liver function-based method for determining the minimum RLV.

摘要： Applying plant community diversity techniques and SPSS statistic analysis, we quantified the relationship between crown volume of 18 (Sophora japonica) tree communities and elevation along different elevation gradient in Ye County in the study. We concluded that there was a significantly positive correlation between crown volume of 18 (Sophora japonica) tree communities and elevation gradient (P Sophora japonica) tree communities increased along elevation from 50 m to 200 m in Ye County in 2018. Therefore, understanding dynamic connecting crown volume of 18 (Sophora japonica) communities and elevation can be not just applied to preserve of (Sophora japonica) tree communities, but also applied to sustainable of biodiversity and processes of tree community’s crown volume along elevation.

摘要： Purpose: Dosimetric study to evaluate impact of “beam” reduction in AVM radiosurgery on normal brain dose parameters and it’s clinical implications. Materials and Methods: Five small volume AVMs (nidus volume 0.31 - 1.94 cc) planned for single fraction SRS with robotic radiosurgery system. Planning scans done with CT scan brain, CT & MR angiography, then nidus volume and organ at risk (OARs) were contoured. Planning was done with multiplan planning system. Plan evaluated as per Flickenger model parameters of 12 Gy nomal brain vol & marginal dose. 7.5 mm and 10 mm cons used, optimization done with seqential algorithm. 20 Gy was prescribed to isodose with appropriate nidus coverage (>98%). Total beams of five plans were 85 - 250, monitor unit 17,259 - 24,602 MU. 12 Gy normal brain volume is 0.9 - 7.6 cc. Then beam reduction is done by reducing beams with minimum MU in steps of 50, 100, 150, 200, 250 MU and after beam reduction, re-optimization done. Prescription isodose was changed to keep the nidus coverage > 98%. Impacts of beam reduction on 12 Gy normal brain vol and conformity/homogeniety index were analyzed. Results: Optimal plans of five patients with 20 Gy prescribed to 88% - 90% isodose, nidus coverage more than 98%. In dosimetric parameters, mean CI was 1.36 - 1.51, nCI 1.41 - 1.51, HI 1.1 - 1.4 and mean 12 Gy normal brain volume 0.17, 1.44, 5.3, 5.5 and 7.6cc respectively. After beam reduction of less than 50 MU contribution (in case#1), prescibing at suitable isodose (85%) beam reduces to 79 and 12 Gy volume marginally increases to 26.4 cc. Beam reduction of less than 100 MU reduces to 53 - 92 beamlets. Reduction of beams with less than 150 MU contribution did not significantly change the 12Gy normal brain volume. However, reduction of beamlets with more than 200 MU, 250 MU, 300 MU, 450 MU and 550 MU significantly affects the 12 Gy normal brain volume. Prescription-isodose modified from 83% to 50% to have >98% coverage. CI and HI increased from 1.36 - 1.51 to 2.51 - 2.63 and 1.1 - 1.4 to 1.52 - 1.54 respectively. There was exponential increase in 12 Gy volume with reduction of beams with higher proportion in larger nidus. Conclusions: In robotic radiosurgery system, beam reduction even after re-optimization impairs the conformity index and increase 12 Gy normal brain volume, hence long-term toxicity. Optimal beam numbers are required for optimal plan generation.

摘要： In the oil and gas industry, water is essential element since it exists in most of the stages, starting from drilling operations, then production processes including injecting in the reservoir to maintain the pressure, and finally disposing the produced water from the reservoir. Therefore, it is very important to understand the water in the petroleum industry with its different types and study its effects on the reservoirs as well as the downhole and surface equipment. Most of the studies and literature reviews focused on the oil and gas properties. In fact, understanding the properties of the water is as important as the oil and gas properties. Water is always present in the oil and gas fields during production, injection or disposal. Therefore, it has a direct impact on the productivity and overall efficiency of the field and the entire development project. This paper is going to illustrate and focus on several objectives. First, it elaborates the importance of the water in the oil and gas fields. Then, it includes a comprehensive overview of different types of water in the petroleum industry including a summary about of their properties. The main two types that the paper focuses on are the produced water and the injected water. It clarifies the effects of both of them on the reservoir, well completions and facilities. After that, the paper touches bases on the common problems and issues caused by water along with a brief summary of steps needed by the operators to follow in order to solve them. In addition to that, the common monitoring procedures and tests that are usually followed to observe the quality of the water are going to be presented. Finally, couples of solutions used by operators are reviewed to solve the problem of excessive water production after the water breakthrough in the field.

摘要： 一种利用Volume R‑CNN神经网络进行运算的方法和装置，包括：获取同一样本的不同角度的多个图像；利用RPN确定样本检测的推荐区域；利用Fast R‑CNN预测推荐区域中对象的类别和边框；根据预测的对象的边框，利用Volume R‑CNN预测每个对象所占的体积比例；根据Fast R‑CNN预测的对象类别以及Volume R‑CNN预测的对象体积比例，计算出不同类别对象的体积比例；其中，所述RPN、Fast R‑CNN和Volume R‑CNN共享卷积层。本发明可以测量复杂、多种类的样品，通过采用人工神经网络技术和芯片，对不同种类对象的识别更加精确和快速。

摘要： 本发明基于EPI_Volume的LF_SURF光场图像特征匹配方法，具体按照以下步骤实施：步骤1、将第一张光场图像读入至MATLAB软件中得到光场图像五维矩阵[s,t,u,v,3]；步骤2、计算得到四维水平EPI_Volume矩阵、四维垂直EPI_Volume矩阵；步骤3、进行SURF特征点检测得到光场图像精确特征点；步骤4、每个光场图像精确特征点生成128维特征描述向量；步骤5、将第一张光场图像的特征点与第二张光场图像的特征点按照欧式距离进行相似性度量进而完成特征点匹配；步骤6、根据特征匹配的精确率对特征匹配的正确性进行验证。本发明基于EPI_Volume的LF_SURF光场图像特征匹配方法，克服了现有的光场图像特征检测方法检测出的特征点不稳定，计算复杂度高，没有对特征点进行描述做进一步匹配的问题。

摘要： 一种利用Volume R‑CNN神经网络进行运算的方法和装置，包括：获取同一样本的不同角度的多个图像；利用RPN确定样本检测的推荐区域；利用Fast R‑CNN预测推荐区域中对象的类别和边框；根据预测的对象的边框，利用Volume R‑CNN预测每个对象所占的体积比例；根据Fast R‑CNN预测的对象类别以及Volume R‑CNN预测的对象体积比例，计算出不同类别对象的体积比例；其中，所述RPN、Fast R‑CNN和Volume R‑CNN共享卷积层。本发明可以测量复杂、多种类的样品，通过采用人工神经网络技术和芯片，对不同种类对象的识别更加精确和快速。

摘要： 本发明涉及三维重建技术领域，提供一种Volume重建范围的扩展方法及系统，所述方法包括下述步骤：在GPU显存中申请一个空的Volume，控制Volume计数器加一，并对空的Volume进行初始化操作；对相机的移动进行跟踪，获取相机当前的位姿参数，根据相机的位姿参数判断相机的移动，以此判定执行切换Volume或重建Volume的动作，从而实现在保持重建速度和重建精度的前提下，有效对重建范围进行扩展，而且在来回切换场景时，无需Volume重建，提高了系统的稳定性。