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CPFinder: Finding an unknown caller's profession from anonymized mobile phone data

Digital Communications and Networks 2022年第3期8卷 324-332页

作者： jiaquan zhang Hui Chen Xiaoming Yao Xiaoming Fu Institution of Computer Science University of GöttingenGöttingen37077Germany Beijing Foreign Studies University Beijing100089China Cloud Branch China TelecomBeijing100033China

Identifying an unfamiliar caller's profession is important to protect citizens' personal safety and property. Owing to the limited data protection of various popular online services in some countries, such as taxi hailing and ordering takeouts, many users presently encounter an increasing number of phone calls from strangers. The situation may be aggravated when criminals pretend to be such service delivery staff, threatening the user individuals as well as the society. In addition, numerous people experience excessive digital marketing and fraudulent phone calls because of personal information leakage. However, previous works on malicious call detection only focused on binary classification, which does not work for the identification of multiple professions. We observed that web service requests issued from users' mobile phones might exhibit their application preferences, spatial and temporal patterns, and other profession-related information. This offers researchers and engineers a hint to identify unfamiliar callers. In fact, some previous works already leveraged raw data from mobile phones (which includes sensitive information) for personality studies. However, accessing users' mobile phone raw data may violate the more and more strict private data protection policies and regulations (e.g., General Data Protection Regulation). We observe that appropriate statistical methods can offer an effective means to eliminate private information and preserve personal characteristics, thus enabling the identification of the types of mobile phone callers without privacy concerns. In this paper, we develop CPFinder —- a system that exploits privacy-preserving mobile data to automatically identify callers who are divided into four categories of users: taxi drivers, delivery and takeouts staffs, telemarketers and fraudsters, and normal users (other professions). Our evaluation of an anonymized dataset of 1,282 users over a period of 3 months in Shanghai City shows that the CPFi

关键词： Mobile big data Profession prediction Machine learning Classification Privacy protection

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Light attenuation cross-section of black carbon in an urban atmosphere in northern China

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Particuology 2015年第1期13卷 89-95页

作者： Junji Cao Chongshu Zhu Kinfai Ho Yongming Han Zhenxing Shen Changlin Zhan jiaquan zhang Key Laboratory of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of Sciences Institute of Global Environmental Change Xi'an Jiaotong University The Jockey Club School of Public Health and Primary Care The Chinese University of Hong Kong Department of Environmental Science and Engineering Xi'an Jiaotong University School of Environmental Science and Engineering Hubei Polytechnic UniversityHubei Key Laboratory of Mine Environmental Pollution Control and Remediation

Fine particulate matter （PM2.5） samples were collected over two years in Xi＇an, China to investigate the relationships between the aerosol composition and the light absorption efficiency of black carbon （BC）. Real-time light attenuation of BC at 880 nm was measured with an aethalometer. The mass concentrations and elemental carbon （EC） contents of PM2.5 were obtained, and light attenuation cross-sections （σATN） of PM2.5 BC were derived. The mass of EC contributed -5% to PM2.5 on average. BC σATN exhibited pronounced seasonal variability with values averaging 18.6, 24.2,16.4, and 26.0 m^2/g for the spring, summer, autumn, and winter, respectively, while averaging 23.0 m^2/g overall. σATN varied inversely with the ratios of EC/PM2.5, EC/[SO4^2- ], and EC/[NO3-]. This study of the variability in σATN illustrates the complexity of the interactions among the aerosol constituents in northern China and documents certain effects of the high EC, dust, sulfate and nitrate loadings on light attenuation.

关键词： Light attenuation cross-section Elemental carbon Dust Xi'an

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Identification of coexistence of biological and non-biological aerosol particles with DAPI (4′,6-diamidino-2-phenylindole) stain

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Particuology 2023年第1期72卷 49-57页

作者： Ting Liu jiaquan zhang Junji Cao Han Zheng Changlin Zhan Hongxia Liu Lili zhang Kai Xiao Shan Liu Dong Xiang Daizhou zhang School of Environmental Science and Engineering Hubei Polytechnic UniversityHubei Key Laboratory of Mine Environmental Pollution Control and RemediationHuangshi 435003China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China School of Computer Science and Artificial Intelligence Wuhan University of TechnologyWuhan 430063China Faculty of Environmental and Symbiotic Sciences Prefectural University of KumamotoKumamoto 862-8502Japan

The fluorescent dye 4′,6-diamidino-2-phenylindole (DAPI) has been widely used to stain microorganisms in various environment media. We applied DAPI fluorescence enumeration to airborne microorganisms and found that non-biological particles, including organic compounds, minerals, and soot, were also visible upon exposure to UV excitation under fluorescence microscope. Using laboratory-prepared biological particles as the control, we investigated the feasibility of identifying both biological and non-biological particles in the same sample with DAPI staining. We prepared biological (bacterial, fungi, and plant detritus) and non-biological (biochar, soot, mineral, metal, fly ash, salt) particles in the laboratory and enumerated the particles and their mixture with DAPI. We found that mineral particles were transparent, and biochar, soot, metals and fly ash particles were black under a filter set at excitation 350/50 nm and emission 460/50 nm bandpass (DAPI-BP), while biological particles were blue, as expected. Particles of the water-soluble salts NaCl and (NH_(4))_(2)SO_(4) were yellow under a filter set at excitation 340–380 nm and emission 425 nm long pass (DAPI-LP). Case studies with samples of dustfall, atmospheric aerosols and surface soils could allow for the quantification of the relative number of different types of particles and particles with organic matter or salt coating as well. Fluorescence enumeration with DAPI stain is thus able to identify the co-existence of biological and non-biological particles in the air, at least to the extent of those examined in this study.

关键词： 4',6-diamidino-2-phenylindole(DAPI) Biological particles Nonbiological particles Atmospheric aerosols

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Pulsation Treatment on the Modification of Crystal with Cold Simulation

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 20-23页

作者： Jianzhong Wang Yong Tang Daqiang Cang jiaquan zhang(Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Since the separation of crystal of KCl saturated aqueous is similar to the crystallization of liquid metals, the melts nucleation can be simulated by the experiment of the crystal of salt aqueous solution. In this experiment pulsation treatment was imposed on KCl saturated aqueous in order to study the effect of pulsation treatment on crystallization in the salt solution, and the influence of different pulsation treating time, super-heating and bine of prescription were investigated. The results show that it is possible to modify the crystallization over satured solution temperature and the degree of under-cooling for salt crystal separation was reduced by applying pulse treating on KCl saturated aqueous solution. In addition, this technology may generate embryos for nucleation even at the temperature over melting point or satured solubility.

关键词： saturated aqueous solution pulse modification treatment nucleation, crystal

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Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

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Frontiers of Environmental Science & Engineering 2012年第2期6卷 177-183页

作者： jiaquan zhang Shihua QI Xinli XING Lingzhi TAN Wei CHEN Ying HU Dan YANG Chenxi WU State Key Laboratory of Biogeology and Environmental Geology and School of Environmental StudiesChina University of GeosciencesWuhan 430074China School of Environmental Science and Engineering Huangshi Institute of TechnologyHuangshi 435003China

Soil is an important source to other environ- mental media and organisms for organochlorine pesticides （OCPs） bioaccumulation. Twenty-four representative sur- face soil samples were collected from the lower reaches of the Jiulong River, China, in 2009. The concentrations of hexachlorocyclohexane isomers （HCHs） ranged from 0.38 to 39.52 ng.g~, with a mean value of 9.51 ng.g-~. The concentrations of dichlorodiphenyltrichloroethanes （DDTs） and their metabolites were within the ranges of 0.94-700.99 ng. gl, with a mean value of 71.17 ng. g-1. The concentrations of HCHs and DDTs in the soil were lower than the first grade level （50 ng. g-a） of the Chinese Environmental Quality Standard （GB 15618-1995）. Hier- archical Cluster Analysis （HCA） and Pearson＇s bivariate Correlations Analysis （PCA） were used to analyse the distribution and contamination levels of OCPs in this region. The results showed that DDTs were the major contaminants and there were no significant correlations between various OCPs concentrations and the total organic carbon （TOC） contents. A significant positive correlation was observed between HCHs and DDTs （p 〈 0.01）, which indicates that HCHs and DDTs may have similar sources and fate in the study area.

关键词： Jiulong River hexachlorocyclohexane (HCH)and dichlorodiphenyltrichloroethan (DDT) classification,Hierarchical Cluster Analysis (HCA) Pearson's bivariateCorrelations Analysis (PCA)

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Fate of PM2.5-bound PAHs in Xiangyang, central China during 2018 Chinese spring festival: Influence of fireworks burning and air-mass transport

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Journal of Environmental Sciences 2020年第11期32卷 1-10页

作者： Tianpeng Hu Yao Mao Weijie Liu Cheng Cheng Mingming Shi Zhanle Chen Qian Tian jiaquan zhang Shihua Qi Xinli Xing Laboratory of Basin Hydrology and Wetland Eco-restoration School of Environmental StudiesChina University of GeosciencesWuhan 430078China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China School of Environmental Science and Engineering Hubei key Laboratory of Mine Environmental Pollution Control and RemediationHubei Polytechnic UniversityHuangshi 435003China

Variations of levels,possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM2.5 during 2018 Chinese Spring Festival(CSF)in Xiangyang City,central China which is the North-South pollutant airmass transport channel of *** 37 samples were *** concentrations of 16 PAHs for the Pre–CSF day(Pre–CSFD),during the CSF day(CSFD)and after the CSF day(Af–CSFD)are 33.78±17.68 ng/m3,22.98±6.49 ng/m3,and 8.99±4.44 ng/m3,*** resolution samples showed that 16 PAHs are higher in the morning(06:00–11:00)or afternoon(11:30–16:30),than those in the evening(17:00–22:00)and at night(22:30–05:30),whereas the result is reversed during the *** burning can obviously increase the mass concentration of *** mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast,and the sources of the northeast and *** air mass only can be transmitted out through northeast and *** is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local *** burning was an important source for PAHs during CSFD,biomass,coal combustion,and traffic emission were the main sources of PAHs for Pre–CSFD and Af–CSFD *** health risk on the CSFD was higher than the acceptable levels,especially during the intensive fireworks burning,the risk value far exceed 1.0×10^-4,controlling burning fireworks is required.

关键词： PAHs Fireworks burning Air mass trajectory Source identification Incremental lifetime cancer risk

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Research on low emission MSW gasification and melting system

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Frontiers of Environmental Science & Engineering 2007年第4期1卷 498-503页

作者： XIAO Gang NI Mingjiang CHI Yong JIN Yuqi zhang jiaquan MIAO Qi CEN Kefa State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory on Clean Coal Power Generation and Combustion Technology of MOE Southeast UniversityNanjing 210096China

In order to eliminate secondary pollution caused by municipal solid waste(MSW)incineration,a MSW gasification and melting process is *** process is expected to reduce the emission of pollutants,especially heavy-metals and *** this paper,the combustible components of MSW and simulated MSW were gasified in a lab-scale fluidized bed at 400°C-700°C when the excess air ratio(ER)was between 0.2 and *** experimental results indicated that the MSW could be gasified effectively in a fluidized bed at approximately 600°C-700°C when excess air ratio was *** melting characteristics of two typical fly ash samples from MSW incinerators were *** results indicated that fly ash of pure MSW incineration could be melted at approximately 1,300°C and that of MSW and coal co-combustion could be melted at approximately 1,400°*** temperature was over 1,100°C,more than 99.9%of the dioxins could be decomposed and most of the heavy-metals could be solidified in the *** on the above experiments,two feasible MSW gasification and mel-ting processes were proposed for low calorific value MSW:(1)sieved MSW gasification and melting system,which was based on an idea of multi-recycle;(2)gasification and melting scheme of MSW adding coal as assistant fuel.

关键词： municipal solid waste(MSW) low emission gasification and melting dioxins heavy-metal

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基于Ce变质处理的TWIP钢凝固组织细化

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金属学报 2020年第5期56卷 704-714页

作者：李根兰鹏张家泉北京科技大学冶金与生态工程学院北京100083

通过真空感应熔炼制备了成分为Fe-22Mn-0.65C的奥氏体TWIP钢,揭示了Ce含量及过热度对TWIP钢凝固组织细化的影响。基于FactSage 7.0热力学软件及错配度模型预测了Ce在TWIP钢中的变质产物及其非均质形核有效性,采用OM、SEM、EBSD、EPMA等... 详细信息

通过真空感应熔炼制备了成分为Fe-22Mn-0.65C的奥氏体TWIP钢,揭示了Ce含量及过热度对TWIP钢凝固组织细化的影响。基于FactSage 7.0热力学软件及错配度模型预测了Ce在TWIP钢中的变质产物及其非均质形核有效性,采用OM、SEM、EBSD、EPMA等手段对不同条件下凝固组织变质处理效果进行定量研究。结果表明,随Ce含量升高,其在TWIP钢中的反应产物由Ce2O3向Ce2O3+少量Ce2O2S转变,而2种粒子理论上均可作为有效形核核心;Ce变质处理后,TWIP钢试样铸态组织等轴晶率从25%升至72%,等轴晶平均尺寸由480μm减小到130μm,Mn元素偏析比由1.61降至1.41;降低变质处理温度时,含Ce粒子团聚倾向减小,TWIP钢凝固组织细化的效果更显著。本工作中建议的变质处理参数为过热度20℃时加入(0.02%~0.04%)Ce。

关键词： Ce TWIP钢变质处理凝固组织细化显微偏析

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Value of whole body diffusion weighted imaging in diagnostic and therapeutic evaluation of malignant lymphoma

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The Chinese-German Journal of Clinical Oncology 2011年第2期10卷 111-115页

作者： Xingrong Hu Ruizhi Ran jiaquan zhang Shunzhen Li Department of Imaging The Central Hospital of Enshi Autonomous Prefecture Enshi 445000 China

Objective:The aim was to evaluate the role of whole body diffusion weighted imaging(WB-DWI) of magnetic resonance in the diagnosis and efficacy evaluation of malignant ***:The clinical manifestation of whole body diffusion weighted imaging of 47 patients with malignant lymphoma being pathologically proved were carried on by retrospective analysis and to compare with 10 healthy *** were 8 cases of Hodgkin's lymphoma(HD) patients,of which WB-DWI examination of 5 cases were carried out before and after treatment and 3 cases were done after *** were 39 cases of non-Hodgkin's lymphoma(NHL) patients,of which WB-DWI examination in 19 cases were acted before treatment,11 cases were done before and after treatment and 9 cases done after *** apparent diffusion coefficient(ADC) diagram the ADC values of lymph nodes in patients with malignant lymphoma and healthy volunteers were measured respectively,among 16 patients the ADC values of parts of lymph node being consistent with the initial inspection were determined again and compared the values before and after,and compared with healthy ***:Whole body magnetic resonance diffusion weighted imaging(MR-DWI) showed more sensitive to lymphoma,and 372 lymph nodes greater than 1 cm were detected with *** treatment,mean ADC value of 35 patients with malignant lymphoma was(0.86 ± 0.21) × 10-3 mm2/s,of which an average ADC values of 28 cases after treatment was(1.22 ± 0.31) × 10-3 mm2/s,before and after treatment difference of the average ADC values of patients was statistically significant(P 0.05).Conclusion:WB-DWI and ADC values being measured in the

关键词： lymphoma magnetic resonance imaging diffusion weighted imaging apparent diffusion coefficient

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基于恒过热控制的感应加热中间包内钢水的流动与传热

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金属学报 2020年第12期56卷 1629-1642页

作者：唐海燕李小松张硕张家泉北京科技大学冶金与生态工程学院北京100083

通过建立电磁-热-流动耦合数学模型,研究了一种六流H型通道感应加热中间包内电磁力的作用特点、钢水的流动及传热规律。对比了感应加热不同应用模式下中间包内流场和温度场特点,探讨了传统冷态水模拟研究方法对该感应加热中间包结构优... 详细信息

通过建立电磁-热-流动耦合数学模型,研究了一种六流H型通道感应加热中间包内电磁力的作用特点、钢水的流动及传热规律。对比了感应加热不同应用模式下中间包内流场和温度场特点,探讨了传统冷态水模拟研究方法对该感应加热中间包结构优化的适用性。结果表明,感应加热中间包通道内电磁力呈偏心分布,方向指向通道偏心位置,钢液在通道内旋转流出。裸包方案下,开启感应加热1500 s时比未开启中间包内1号水口处钢水温度高22 K;由于电磁力作用使通道附近水口的短路流加剧、各流一致性变差。但中间包结构优化后,通道附近水口短路流消失,各流温差降低、一致性改善、升温速率加快。模型研究结果揭示了这种新型中间包的冶金机理,同时也表明基于冷态模拟的中间包结构优化方法仍可作为感应加热中包结构设计和优化的重要依据。

关键词：感应加热中间包电磁力温度场流场结构优化

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