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一种新的活动轮廓模型图像分割方法
刘晨,,,宗虎
- , 2017, DOI: 10.15961/j.jsuese.201600500
Abstract: 中文摘要: 局部二值拟合模型利用图像的局部邻域信息拟合能量函数,局部二值拟合模型相当于对活动轮廓内外进行局部均值滤波,因此该模型对高斯噪声有一定的抗噪性,但是该模型对椒盐噪声污染的图像不能取得令人满意的分割结果。为了提高活动轮廓模型对椒盐噪声的鲁棒性,结合局部二值拟合模型中的局部拟合项,提出一种能消除椒盐噪声影响的新的局部拟合项。提出的拟合项的能量函数极小值是局部区域的中值,新的拟合项相当于对活动轮廓内外进行局部中值滤波,中值滤波对椒盐噪声不敏感。原模型中边缘停止函数是基于图像梯度信息,难以区分图像不同区域间模糊的弱边缘和灰度渐进图像目标,并且容易受到各类噪声的影响,抗噪声能力弱。提出一种新的边缘检测算子,重新定义边缘停止函数,进一步提高模型的抗噪性,降低高斯噪声和椒盐噪声对分割结果的影响。为了保持活动轮廓在演化过程中的稳定性,在曲线演化迭代过程中必须周期地初始化以使水平集函数重新变成带符号的距离函数,但重新初始化的计算量大。引入一个惩罚能量,解决水平集函数在演化过程中的重新初始化难题。对不同噪声污染的图像进行试验的结果表明,提出的模型可以取得较好的图像分割结果,比CV模型、LBF模型和LIF模型更具有优势。
Abstract:The local binary fitting(LBF) model fits energy function with local neighborhood information of the image. Since it is equivalent to the local average filtering inside and outside the active contour, LBF has some noise immunity for Gaussian noise. However, it cannot obtain satisfactory segmentation results for salt and pepper noise. In this paper, a novel model integrating a local fitting term into the fitting term of LBF was proposed to enhance the robustness for the salt and pepper noise. The new fitting term was equivalent to the local median filtering inside and outside the active contour, which is insensitive to the salt and pepper noise. As the edge stop function of the original model is based on image gradient information, which is difficult to distinguish the weak edge of the image and is sensitive to all kinds of noise, a new edge detection operator was proposed to redefine the edge stop function to further improve the noise immunity of the model. In order to keep the stability of the active contours, the original model must be periodically initialized to ensure the level set function be a signed distance function and the re-initialization performs a large amount of computation. In our model, a punish energy term was introduced to eliminate the re-initialization. Compared with CV model, LBF model and LIF mode, experiments on images corrupted by different noise demonstrated that the proposed model was effective and more superior for noise image segmentation.
小浪底水库下游游荡性河段模型试验研究
红武,刘海凌,董年虎,赵新建,,曹永
人民黄河 , 2000,
Abstract: ?依据黄河动床模型相似律完成了小浪底水库下游游荡性河段模型的设计.验证试验结果表明:模型满足水流运动相似、阻力相似、泥沙运动相似、河床变形相似等条件,且通过验证试验选取的河床变形时间比尺与水流运动时间比尺基本一致,从而避免了因时间变态引起的一系列问题.利用该模型对小浪底水库运用后游荡性河道河床演变规律和将出现的问题进行了预估,并先后完成了洪水预报和河道整治方案检验试验.
小浪底水库运用初期小浪底至苏泗庄河段模型试验研究
红武,刘海凌,董年虎,赵新建,曹永,
人民黄河 , 2000,
Abstract: ?利用小浪底至苏泗庄河段动床模型开展了有小浪底水库调节(调控上限流量为3700m3/s)和无小浪底水库两种方案的试验。研究了小浪底水库运用初期下游河道将出现的变化。此外,还进行了小浪底水库2000年调控流量2000、2600m3/s及自然滞洪3种方案的试验,为水库2000年运用方案的决策提供科学依据。
基于π定理的崩落法转充填法过渡采场顶柱尺寸研究
刘艳章,邓磊,王其飞,赵卫,石志军,,
采矿与安全工程学报 , 2015,
Abstract: 崩落法转充填法开采过程中,充填法过渡采场顶柱下方存在采空区,顶柱上部有大量崩落法开采留下的松散岩石,顶柱的稳定性对过渡段矿石的安全开采具有重要意义。过渡采场顶柱厚度与跨度之比即厚跨比r是影响过渡采场顶柱稳定性的重要因素之一,为了分析顶柱稳定性,采用π定理建立了充填法过渡采场顶柱厚跨比r和顶柱稳定性的关系模型,该模型选取顶柱的许用应变作为采场稳定性判断标准,根据许用应变得到合理的厚跨比。将此关系模型应用于程潮铁矿无底柱分段崩落法转充填法的试验过渡采场顶柱尺寸研究中。运用有限元法计算得出程潮铁矿过渡采场顶柱的最小厚跨比rmin,根据损失率约束得出最大的厚跨比rmax。通过计算厚跨比r的取值为1.24~1.45。试验采场按此厚跨比进行生产,顶柱未失稳。工程试验检验了此关系模型的有效性。
ICP-MS/MS检测食品中磷、硒、砷的含量

- , 2017, DOI: 10.13982/j.mfst.1673-9078.2017.7.041
Abstract: 研究建立了ICP-MS/MS检测食品中磷、砷和硒含量的检测方法。分析了P、As和Se在检测过程中常见的质谱干扰和电离效率,比较了标准模式(No Gas)、He模式、H2模式、O2模式以及双四极杆等各种检测模式,发现采用O2模式双质谱对P、Se的检测结果最为准确,As采用He模式即可实现精准检测。根据优化后的检测条件,经过Q1时同位素M进入碰撞反应池,与O2反应生成的氧化物MO进入Q2被采集,通过二级质谱质量转移几乎可以彻底消除一切干扰。结果显示,P在2.0~500 μg/L范围内、As和Se在0.5~200 μg/L浓度范围内均具有良好的线性,相关系数均大于0.9995,加标回收显示回收率在94.0~101.5%之间,RSD%不大于2.1%。最终采用该方法对国家标准物质乳粉样品(GBW 10017)、螺旋藻(GBW 10025)进行测定,结果均在标准值范围内。本方法可以满足食品中P、As和Se等元素的精准检测。
A method for the determination of phosphorus, arsenic, and selenium contents in foods by inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) was established. The common mass spectral interference and ionization efficiency during measurements of phosphorus, arsenic, and selenium were analyzed, and the standard mode (no gas), helium mode, hydrogen mode, oxygen mode, and double quadrupole detection mode were compared. The most accurate results for phosphorus and selenium detection were obtained by using the oxygen mode and dual mass spectrometry, and the helium mode could be used for the accurate detection of arsenic. According to the optimized detection conditions, the isotopes of M entered the collision cell after Q1, and reacted with oxygen to form the oxide MO, which entered into Q2. Mass transfer of the tandem mass spectrum could almost eliminate all interference. The results showed that good linear calibration curves were obtained in the range of 2.0~500 μg/L for phosphorus and 0.5~200 μg/L for arsenic and selenium, and the correlation coefficients were over 0.9995. The recoveries were in the range of 94.0~101.5%, and the relative standard deviations (RSDs%) were not more than 2.1%. Finally, national standard substance milk powder sample (GBW10017) and Spirulina (GBW10025) were analyzed using this method, and the results were all within the standard value range. Therefore, the method can meet the requirements for the accurate detection of phosphorus, arsenic, and selenium in food.
板式换热器铁细菌生物污垢特性的实验分析
徐志明,贾玉婷,,一龙,刘坐东,王景
化工学报 , 2014,
Abstract: 为探讨铁细菌在板式换热器里的污垢规律,本文对不同流速、温度及浓度下铁细菌在板式换热器内的污垢特性进行了实验研究。结果表明:随着流速的增加,铁细菌的污垢热阻渐近值逐渐减小;随着温度的升高,铁细菌的结垢诱导期明显缩短,结垢速率加快,污垢热阻的渐近值呈减小的趋势;而随着浓度的增加,污垢热阻值呈现明显幅度的增长。
胆源性慢性胰腺炎的病因及手术方法探讨
田伏洲,骆助林,,任建东,汤礼军,庞勇,黎冬宣,,
解放军医学杂志 , 2010,
Abstract: [摘要]目的?探讨胆源性慢性胰腺炎(BCP)的病因及其有效的治疗方法。方法??收集1997年1月-2007年1月于成都军区?总医院临床确诊的BCP患者41例,其中男24例,女17例,年龄32~57岁,病程2~9年。观察其临床表现,检测其胆汁中淀粉酶的?含量或胰液中胆红素的含量,观察胰胆管合流方式,测量其共同通道的长度。本组41例全部首选内镜Oddi括约肌切开术(EST),13?例患者接受胆胰分流外科手术(BPS)。术后采用视觉模拟评分法(VAS)评估疼痛强度,出院后采用电话询问及定期医院复查的方法?进行随访。结果??41例中,32例发现存在胆胰反流的证据。EST手术成功治愈8例;行BPS手术的13例均获成功,达治愈标准者?12例。结论??胆胰反流可能是BCP的重要原因。BPS手术可应用于EST治疗失败的BCP病例,疗效满意。
The effect of strong magnetic field on proton branch of modified URCA process
强磁场中修正URCA过程的中微子产能率

Zhang Jie,Liu Men-Quan,Wei Bing-Tao,Luo Zhi-Quan,
,刘门全,,罗志全

物理学报 , 2008,
Abstract: The neutrino energy loss rate of modified URCA process in strong magnetic field of neutron star core is investigated based on the n-p-e model. Both neutron and proton branches of modified URCA process are considered. The result shows that a strong magnetic field makes the neutrino energy loss rate of modified URCA process to oscillate intensively. Compared with the neutron branch, neutrino energy loss rate of the proton branch is weaker. But the total neutrino energy loss rate will increase due to the proton branch of modified URCA processes. The result will contribute to the research of cooling mechanism of neutron stars.
极化条件对偶氮化合物薄膜中分子取向的影响
刘云龙,王文军,孙彦星,高学喜,,俞宪同,赵力,邢晓
强激光与粒子束 , 2011,
Abstract: ?为探索不同的极化条件对分子取向的影响,用旋涂法制备了偶氮主客体掺杂薄膜,并用电晕极化的方法分别在不同温度和厚度条件下使分子取向,通过测量极化前后紫外-可见吸收谱,研究了平均取向因子的变化,并和二次谐波产生结果进行了比较。实验结果表明:对于厚度相同的偶氮薄膜,随着温度的升高,平均取向因子增大,但二次谐波信号强度先增大后减小;温度越接近聚合物玻璃转变温度,分子越容易取向,但温度过高,聚甲基丙烯酸甲酯变为粘滞态,部分偶氮分子容易在高温下蒸发掉,导致二次谐波信号强度降低,而平均取向因子增大;随着薄膜厚度的增大,针-板电极电场造成薄膜内部电场分布的不均匀性增加,极化效率降低,平均取向因子不断减小,二次谐波信号强度先增大后减小。
城乡一体化背景下职业教育存在问题及对策探析
On the Basis of Urban-Rural Integration and Research on Problems and Countermeasures of Vocational Education
 [PDF]


Vocational Education (VE) , 2012, DOI: 10.12677/ve.2012.11001
Abstract:

目前,在我国城乡一体化建设过程中,专业技能型人才需求有很大的缺口,在一定程度上制约了城乡一体化建设的开展,而职业教育是培养技能人才的重要途径,正确指导职业教育的发展对促进我国城乡一体化建设具有非常重大意义。对此,本文探析了城乡一体化建设对职业教育发展的要求以及职业教育存在的问题,并根据城乡一体建设的发展要求提出了职业教育发展的对策,以期职业教育在促进我国城乡一体化建设中发挥更大的作用。
At present, in the process of urban and rural integration, a wide gap of professional skilled per- sonnel, restricting the carrying out of the urban-rural integration, and vocational education is an important way to cultivate skilled personnel, the correct guide on the development of vocational education in promoting the integration of urban and rural areas have very great significance. In this regard, this paper explores the requirements for the development of vocational education and vocational education in urban and rural inte- gration problems, based on the development of integrated urban and rural construction requirements of the proposed countermeasures of the development of vocational education, vocational education in order to promote the integration of urban and rural play a greater role.

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