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劈裂材检量方法的商榷
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作者 王春香 王丽艳 《吉林林业科技》 2013年第6期52-53,共2页
GB/T144—2003《原木检验》对劈裂材的检量方法进行了规定,但在实际生产中,这些规定有不尽合理之处。本文对其进行了分析,并提出了修改建议。
关键词 劈裂材 检量方法
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世界主要木材出口国家原木检量方法分析
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作者 陈旭东 朱永平 +1 位作者 黄卫国 任晓进 《人造板通讯》 2005年第8期20-24,共5页
关键词 国际贸易 木材 出口贸易 原木 检量方法 森林资源
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简化原木劈裂材检量方法的研究
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作者 罗积长 黄国强 《福建林学院学报》 CSCD 北大核心 2003年第3期229-231,共3页
通过对原木劈裂材的检量与计算存在问题的分析,建议将已脱落劈裂材的检算方法统一改为让径级.
关键词 原木 劈裂材 检量方法 让径级
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基于改进YOLOv8的轻量化小麦病害检测方法 被引量:17
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作者 马超伟 张浩 +3 位作者 马新明 王键霖 张永爽 张小艾 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期187-195,共9页
为提高小麦病害检测精度,实现将模型方便快速部署到移动端,该研究提出了一种基于改进YOLOv8的轻量化小麦病害检测方法。首先,使用PP-LCNet模型替换YOLOv8网络结构的骨干网络,并在骨干网络层引入深度可分离卷积(depthwise separable conv... 为提高小麦病害检测精度,实现将模型方便快速部署到移动端,该研究提出了一种基于改进YOLOv8的轻量化小麦病害检测方法。首先,使用PP-LCNet模型替换YOLOv8网络结构的骨干网络,并在骨干网络层引入深度可分离卷积(depthwise separable convolution, DepthSepConv)结构,减少模型参数量,提升模型检测性能;其次,在颈部网络部分添加全局注意力机制(global attention mechanism, GAM)模块,强化特征中语义信息和位置信息,提高模型特征融合能力;然后,引入轻量级通用上采样内容感知重组(content-aware reassembly of features,CARAFE)模块,提高模型对重要特征的提取能力;最后,使用Wise-IoU(weighted interpolation of sequential evidence for intersection over union)边界损失函数代替原损失函数,提升网络边界框回归性能和对小目标病害的检测效果。试验结果表明,对于大田环境下所采集的小麦病害数据集,改进后模型的参数量及模型大小相比原YOLOv8n基线模型分别降低了12.5%和11.3%,同时精确度(precision)及平均精度均值(mean average precision,m AP)相较于原模型分别提高了4.5和1.9个百分点,优于其他对比目标检测算法,可为小麦病害检测无人机等移动端检测装备的部署和应用提供参考。 展开更多
关键词 图像识别 深度学习 目标 小麦病害 YOLOv8 PP-LCNet
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浅谈有关原木直径检量方法 被引量:1
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作者 王巍奇 《林区教学》 2011年第8期164-165,共2页
通过对国内外的原木直径计量方法的对比,找到一个适合我国林区实际情况的计量方法,提出自己浅薄的建议。
关键词 原木 检量方法
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对世界主要产材国家原木检量方法的研究和分析
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作者 陈旭东 朱永平 《中国木材》 2001年第4期22-25,共4页
关键词 木材 原木检量方法 对比分析 进口木材
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原木检尺常见问题及解决方法 被引量:1
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作者 邹建宇 白宗炎 《农村实用科技信息》 2012年第5期57-57,共1页
不同的国家对原木检量有不同的要求,有不同的检量方法,下面主要从四方面介绍下原木检量应掌握和注意的事项:
关键词 原木 检量方法 解决方法 木材验员
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木材节子的合理利用和检量分析
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作者 王运海 《现代商贸工业》 2011年第20期255-255,共1页
主要是对木材中节子的加工利用和检量方法进行了简要的论述,为木材检验提供参考资料。
关键词 节子 加工利用 检量方法
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A Method for Detecting Adhesive Related-Factors of Streptococcus suis Serotype 2 by Real-time PCR 被引量:1
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作者 汪伟 何孔旺 +9 位作者 倪艳秀 周俊明 张雪寒 俞正玉 吕立新 茅爱华 温立斌 王小敏 李彬 郭容莉 《Agricultural Science & Technology》 CAS 2013年第10期1378-1382,共5页
[Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 (SS2) by fluorescent quantitative PCR. []V... [Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 (SS2) by fluorescent quantitative PCR. []Vlethod] The gene fragments en- coding SS2 adhesive related-factors MRP, FBPS and CPS2J and a housekeeping gene aroA were amplified by reverse transcription PCR from the total RNA of SS2, cloned, and sequenced. The recombinant plasmids containing the target genes were constructed, and used as templates in Real-time PCR. [Result] Dynamic curves, stan- dard curves and melting curves of the adhesive related-factors and aroA were ob- tained by the optimized Real-time PCR system. The standard curves showed a good linear relationship between template copy number and circulation number, and the correlation coefficients (FF) of the standard curves were over 0.995. Also, these as- says were highly specific a^d there was single specific melting peak for every gene. Moreover, the assays were highly sensitive and had a detection limit of 1.0×102 copies in 1 μl of initial templates. Finally, it was highly repeatable and had a coeffi- cient of variation less than 2% for intra-assay. [Conclusion] This study will provide a way to reveal the adhesion mechanism of SS2 to different host cells at molecular level. 展开更多
关键词 Streptococcus suis serotype 2 Adhesive related-factors (adhesins) Real- time PCR
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 Marine magnetic survey instrumental system testing method
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Improved metrics for evaluating fault detection efficiency of test suite
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作者 王子元 陈林 +1 位作者 汪鹏 仉雪玲 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期285-288,共4页
By analyzing the average percent of faults detected (APFD) metric and its variant versions, which are widely utilized as metrics to evaluate the fault detection efficiency of the test suite, this paper points out so... By analyzing the average percent of faults detected (APFD) metric and its variant versions, which are widely utilized as metrics to evaluate the fault detection efficiency of the test suite, this paper points out some limitations of the APFD series metrics. These limitations include APFD series metrics having inaccurate physical explanations and being unable to precisely describe the process of fault detection. To avoid the limitations of existing metrics, this paper proposes two improved metrics for evaluating fault detection efficiency of a test suite, including relative-APFD and relative-APFDc. The proposed metrics refer to both the speed of fault detection and the constraint of the testing source. The case study shows that the two proposed metrics can provide much more precise descriptions of the fault detection process and the fault detection efficiency of the test suite. 展开更多
关键词 software testing test case prioritization fault detection efficiency METRIC
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Capsule endoscopy: Improving transit time and image view 被引量:25
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作者 Zvi Fireman D Paz Y Kopelman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5863-5866,共4页
AIM: To evaluate the effect of various methods of small bowel preparation on the transit time and the quality of visualization of the entire small bowel mucosa. METHODS: Ninety-five patients underwent capsule endosc... AIM: To evaluate the effect of various methods of small bowel preparation on the transit time and the quality of visualization of the entire small bowel mucosa. METHODS: Ninety-five patients underwent capsule endoscopy (CE) by easily swallowing the capsule. They were divided into three study groups according to the preparation used: group A (n = 26) by polyethylene glycol (PEG) liter or with sodium phosphate (SP) 12 h prior to the CE study; group B (n = 29) by erythromycin 1 h prior to the CE study; and group C (n = 40) without any preparation. Visualization ranged from good to satisfactory to poor. RESULTS: The gastric emptying time in the group prepared with erythromycin was shorter but without statistical significance and the small bowel transit time was unaffected. In elderly subjects prepared by PEG or SP, the gastric emptying time was significantly longer (163.7 rain, P = 0.05). The transit times of the three sub-groups were not affected by gender or pathology. The grade of cleaning of the entire study group was 3.27±1.1. The erythromycin group presented significantly the worst quality of images (P = 0.05) compared to the other sub-groups. Age, gender, and pathology had no effect on the quality of the cleaning of the small bowel in the sub-groups. One (1.05%) case had no natural excretion. CONCLUSION: Erythromycin markedly reduces gastric emptying time, but has a negative effect on the quality of the image in the small bowel. The preparation of elderly subjects with PEG or SP has a negative effect on the small bowel transit time. 展开更多
关键词 Capsule endoscopy Gastric emptying time Small bowel transit time VIEW ERYTHROMYCIN Polyethylene glycol
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Novel fiber-optical interferometer with miniaturized probe for in-hole measurements 被引量:3
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作者 Robert Schmitt Tilo Pfeifer +1 位作者 Frank Depiereux Niels Knig 《Optoelectronics Letters》 EI 2008年第2期140-142,共3页
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to en... Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 展开更多
关键词 纤维 光干扰术 测技术 方法
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Microwave digestion polarography for determining seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection simultaneously 被引量:1
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作者 黄熠 张泰铭 +1 位作者 曹娟 梁逸曾 《Journal of Central South University of Technology》 EI 2007年第4期514-519,共6页
The sensitive second derivative waves of Cu(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Fe(Ⅱ)and Mn(Ⅱ),forming in the substrate solution(pH=9.26)consisting of ammonia,ammonium chlorid,gelatin and ascorbic acid were researched.T... The sensitive second derivative waves of Cu(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Fe(Ⅱ)and Mn(Ⅱ),forming in the substrate solution(pH=9.26)consisting of ammonia,ammonium chlorid,gelatin and ascorbic acid were researched.The peak potentials of the polarographic waves of the seven ions are at about 0.48,0.63,0.79,1.04,1.28,1.44 and 1.60 V respectively.Combining with microwave technique,a new method for the simultaneous determination of the seven trace elements in Chinese traditional medicine was developed.The method is easy to operate,rapid,simple and convenient.When the signal-to-noise rate equals 3,the detection limits of Cu,Pb,Cd,Ni,Zn,Fe and Mn are 4.2×10 3,5.3×10 3,2.1×10 3,5.8×10 4,3.0×10 3,7.7×10 4 and 1.1×10 3 μg/mL respectively.Well linear relationships exist between the concentrations and the peak currents when Cu,Pb,Cd,Ni,Zn,Fe and Mn concentrations are within 8.5×10 3 10,9.7×10 3 10,4.5×10 3 10,1.2×10 3 10,6.4×10 3 10,1.5×10 3 10 and 2.8×10 3 10 μg/mL,respectively.The method has been used to the simultaneous determination of the seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection,the relative standard deviations(RSDs)of the Cu,Pb,Cd,Ni,Zn,Fe and Mn in the two medicines are 3.9% and 5.8%,4.0% and 4.1%,4.3% and 5.7%,4.9% and 5.3%,4.4% and 4.7%,3.5% and 4.0%,0.51% and 2.8%,respectively;the comparisons of the determination results with the values obtained by the standard method indicate that the presented method has very well veracity. 展开更多
关键词 derivative polarographic wave microelement Salvia Miltiorrhiza Root compound Salvia Miltiorrhiza Root injection
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Effects of Na^+/K^+ Ratio of Groundwaters on the Gill Ion-Transport Enzyme Activity,Plasma Osmolality and Growth of Cynoglossus semilaevis Juveniles 被引量:2
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作者 YANG Huizan PAN Luqing HU Fawen LIU Hongyu 《Journal of Ocean University of China》 SCIE CAS 2008年第4期447-452,共6页
The effects of environmental Na+/K+ ratio on the gill ion-transport enzyme activity,plasma osmolality and growth of Cynoglossus semilaevis juveniles were investigated. The results showed that,plasma osmolality was sim... The effects of environmental Na+/K+ ratio on the gill ion-transport enzyme activity,plasma osmolality and growth of Cynoglossus semilaevis juveniles were investigated. The results showed that,plasma osmolality was similar among flounder adapted to different Na+/K+ ratios of saline groundwaters (P>0.05),while the growth,gill Na+,K+-ATPase and HCO3--ATPase activities were affected by Na+/K+ ratio significantly (P<0.05). The gill Na+,K+-ATPase activity reached its maximum on day 3,then decreased gradually from day 3 to day 9 and remained constant from day 9 to day 15. The peak values of gill Na+,K+-ATPase activity were detected on day 3 for all Na+/K+ ratios of saline groundwaters,then the enzyme activities descended,and on day 9 the enzyme activi-ties achieved steady state,and the gill HCO3--ATPase activity increased rapidly and achieved steady state after one day. During steady state,the gill Na+,K+-ATPase and HCO3--ATPase activity of Na+/K+ ratios 20 and 40 treatments were significantly higher than those in the control group (Na+/K+ ratio 27.5),while there were no significant differences between the Na+/K+ ratio 30 treatment and the control group; the gill Na+,K+-ATPase activity of Na+/K+ ratio 20 and 40 treatments were significantly higher than that for ratio 30 treatment,but there were no significant differences of gill HCO3--ATPase activity among these treatments. At the end of the 15-day experiment,the weight gain (%) and specific growth rate (SGR) of flounders maintained in seawater were significantly higher than those in groundwaters; significant differences also occurred among the treatments; Na+/K+ ratio 30 treatment had the highest values (33.7% and 1.94 respectively),which were significantly higher than those under Na+/K+ ratios 20 and 40 treatments. There-fore,for the saline groundwater used in this experiment,it is suggested that the Na+/K+ ratio be adjusted to approximately 30,i.e.,as close to that of natural seawater as possible in the culture of flounder. 展开更多
关键词 Na^-/K^- ratio Cynoglossus semilaevi ion-transport enzyme activity plasma osmolality growth
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Computed Tomographic Qualitative Diagnosis of Renal Masses
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作者 叶慧 胡道予 夏军 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第6期369-372,共4页
Objective: To analyze the CT findings of renal masses and to investigate the value of CT imaging in qualitative diagnosis of these diseases. Methods: Twenty-eight cases of renal masses, proven surgically and patholo... Objective: To analyze the CT findings of renal masses and to investigate the value of CT imaging in qualitative diagnosis of these diseases. Methods: Twenty-eight cases of renal masses, proven surgically and pathologically, were retrospectively analyzed. Pre- and post-contrast CT scans were performed in all cases. Results: Twenty-one of 28 cases (75%) were diagnosed as having malignant tumors with 16 cases of renal cell carcinoma (RCC) showing as irregular-shaped low density soft tissue mass with no or slight enhancement. Ten of 21 cases were diagnosed as having carcinoma of the renal pelvis showing as soft tissue mass in renal pelvis with no or slight enhancement. Three of 21 cases were diagnosed as having nephroblastoma (Wilms' tumor) showing as larger irregular lobucated mass with no enhancement. Three of 28 cases (11%) of benign tumors were diagnosed as having angiomyolipoma (AML). Two cases showed a mixed density mass while another case showed iso-density mass. The soft tissue part of the tumor showed enhancement while the area of fat didn't show any enhancement of the contrast medium. Four of 28 (14%) included 3 cases of renal cysts showing as classic cystic lesions with clear-margin. No enhancement was found. In the remaining one case of renal abscess, CT showed a mixed density mass of soft tissue and cyst with slight enhancement of soft tissue part while no enhancement of cystic part. Conclusion: Pre-contrast and post-contrast CT scans in combination with history play an important role in the diagnosis of renal 展开更多
关键词 renal mass computed tomography
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Detecting Encrypted Botnet Traffic Using Spatial-Temporal Correlation 被引量:3
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作者 Chen Wei Yu Le Yang Geng 《China Communications》 SCIE CSCD 2012年第10期49-59,共11页
In this paper, we to detect encrypted botnet propose a novel method traffic. During the traffic preprocessing stage, the proposed payload extraction method can identify a large amount of encrypted applications traffic... In this paper, we to detect encrypted botnet propose a novel method traffic. During the traffic preprocessing stage, the proposed payload extraction method can identify a large amount of encrypted applications traffic. It can filter out a large amount of non-malicious traffic, greatly in, roving the detection efficiency. A Sequential Probability Ratio Test (SPRT)-based method can find spatialtemporal correlations in suspicious botnet traffic and make an accurate judgment. Experimental resuks show that the false positive and false nega- tive rates can be controlled within a certain range. 展开更多
关键词 BOTNET encrypted traffic spatial-tenmporal correlation
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Edge detection using directional eigenvalues of potential field gradient tensor data 被引量:2
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作者 ZHOU Shuai HUANG Danian 《Global Geology》 2015年第3期188-195,共8页
Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We ... Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources. In order to balance strong and weak amplitude anomalies simultaneously,we present one normalization method using different orders of vertical derivatives to improve the new filters. The presented filters were tested on synthetic and real potential field data to verify its feasibility. All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly,but also bring out more geological subtle details. 展开更多
关键词 directional eigenvalues edge detection potential field
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Quantitative Surface Chirality Detection with Sum Frequency Generation Vibrational Spectroscopy: Twin Polarization Angle Approach
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作者 Feng Wei Yan-yan Xu +2 位作者 Yuan Guo Shi-lin Liu Hong-fei Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第6期592-600,J0001,共10页
Here we report a novel twin polarization angle (TPA) approach in the quantitative chirality detection with the surface sum-frequency generation vibrational spectroscopy (SFG-VS). Generally, the achiral contributio... Here we report a novel twin polarization angle (TPA) approach in the quantitative chirality detection with the surface sum-frequency generation vibrational spectroscopy (SFG-VS). Generally, the achiral contribution dominates the surface SFG-VS signal, and the pure chiral signal is usually two or three orders of magnitude smaller. Therefore, it has been difficult to make quantitative detection and analysis of the chiral contributions to the surface SFG- VS signal. In the TPA method, by varying together the polarization angles of the incoming visible light and the sum frequency signal at fixed s or p polarization of the incoming infrared beam, the polarization dependent SFG signal can give not only direct signature of the chiral contribution in the total SFG-VS signal, but also the accurate measurement of the chiral and achiral components in the surface SFG signal. The general description of the TPA method is presented and the experiment test of the TPA approach is also presented for the SFG-VS from the S- and R-limonene chiral liquid surfaces. The most accurate degree of chiral excess values thus obtained for the 2878 cm^-1 spectral peak of the S- and R-limonene liquid surfaces are (23.7±0.4)% and (-25.4±1.3)%, respectively. 展开更多
关键词 Sum-frequency generation vibrational spectroscopy Twin polarization angle approach SURFACE CHIRALITY LIMONENE
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Network Management of Food Additives Quality Analysis and Inspection 被引量:3
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作者 Hairui Zhang Guofu Zhang Li Zhang 《Journal of Chemistry and Chemical Engineering》 2015年第7期468-471,共4页
In this paper, on the basis of the implementation of the national chemical industry standard analytical test methods and analysis of test items, a food additive quality analysis and inspection of network management ap... In this paper, on the basis of the implementation of the national chemical industry standard analytical test methods and analysis of test items, a food additive quality analysis and inspection of network management applications are developed using the development technology of Visual Basic language and computer system operating environment, to achieve a network management software for users on food additives of quality analytical testing. The software sets up an information sharing network platform for enterprise and quality management departments, which is a major innovation in the food additive quality analysis on test management methods and tools. 展开更多
关键词 Food additives quality analysis Visual Basic language network management software development.
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