检索结果-南通市图书馆

International Journal of Automation and computing 2010年第1期7卷 132-136页

作者： Qing-Guo Bai Yu-Zhong Zhang Guang-Long Dong School of Operations Research and Management Sciences Qufu Normal University Rizhao 276826 PRC haiyang municipal public security bureau Haiyang 265100 PRC

This paper presents an economic lot-sizing problem with perishable inventory and general economies of scale cost functions. For the case with backlogging allowed, a mathematical model is formulated, and several properties of the optimal solutions are explored. With the help of these optimality properties, a polynomial time approximation algorithm is developed by a new method. The new method adopts a shift technique to obtain a feasible solution of subproblem and takes the optimal solution of the subproblem as an approximation solution of our problem. The worst case performance for the approximation algorithm is proven to be （4√2 ＋ 5）/7. Finally, an instance illustrates that the bound is tight.

关键词： Economic lot-sizing problem backlogging economies of scale function perishable approximation algorithm

TSE-Tran:Prediction method of telecommunication-network fraud crime based on time series representation and transformer

在线全文

学校读者我要写书评

暂无评论

Journal of Safety Science and Resilience 2023年第4期4卷 340-347页

作者： Tuo Shi Jie Fu Xiaofeng Hu Department of public security Management Beijing Police CollegeBeijing 102202China Environmental security Defense Brigade Beijing MunicipalPublic Security Bureau Miyun BranchBeijing 101599China School of Information Technology and Cyber security People’s Public Security University of ChinaBeijing 100038China

Telecom network fraud has become the most common and concerning type of crime and is an important public security incident that threatens urban ***,preventing a continuous rise in telecommunications and network fraud will help establish a resilient urban governance *** the spatiotemporal forecasting of telecommunications-network fraud trends is of significant importance for aiding public security agencies in proactive crime prevention and implementing targeted anti-fraud *** study presents a telecommunication network fraudulent crime prediction method called TSE-Tran,which integrates temporal representation and transformer *** time-series data of telecommunication-network fraud occurrences were input into the TimesNet module,which maps the sequence data to a more precise feature representation tensor that accounts for both intra-and inter-cycle ***,the data are fed into the transformer-encoder module for further encoding,capturing long-range dependencies in the time-series ***,occurrences of future telecommunication network frauds are predicted by a fully connected *** results of the study demonstrate that the proposed TSE-Tran method outperforms benchmark methods in terms of prediction *** results of this study are expected to aid in the prevention and control of telecommunications and network frauds effectively strengthen the resilience of urban development and the ability to respond to public security incidents.

关键词： Urban resilience TimesNet Transformer Time series prediction Attention mechanism

Aqueous-phase formation of N-containing secondary organic compounds affected by the ionic strength

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第4期138卷 88-101页

作者： Yuqi Gan Xiaohui Lu Shaodong Chen Xinghua Jiang Shanye Yang Xiewen Ma Mei Li Fan Yang Yewen Shi Xiaofei Wang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Shanghai Institute of Pollution Control and Ecological security Shanghai 200092China Guangdong Provincial Observation and Research Station for Coastal Atmosphere and Climate of the Great Bay Area Southern University of Science and TechnologyShenzhen 518055China Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhouChina Environmental Monitoring Station of Pudong New District Shanghai 201200China Shanghai municipal Center for Disease Control&Prevention Shanghai 200336China

The reaction of carbonyl-to-imine/hemiaminal conversion in the atmospheric aqueous phase is a critical pathway to produce the light-absorbing N-containing secondary organic compounds(SOC).The formation mechanism of these compounds has been wildly investigated in bulk solutions with a low ionic ***,the ionic strength in the aqueous phase of the polluted atmosphere may be *** is still unclear whether and to what extent the inorganic ions can affect the SOC *** we prepared the bulk solution with certain ionic strength,in which glyoxal and ammonium were mixed to mimic the aqueous-phase *** characterization by High-resolution Mass Spectrometry was performed to identify the N-containing products,and the light absorption of the mixtures was measured by ultraviolet-visible ***-nine N-containing compounds were identified and divided into four categories(N-heterocyclic chromophores,high-molecular-weight compounds with N-heterocycle,aliphatic imines/hemiaminals,and the unclassified).It was observed that the longer reaction time and higher ionic strength led to the formation of more N-heterocyclic chromophores and the increasing of the lightabsorbance of the *** added inorganic ions were proposed to make the aqueous phase somewhat viscous so that the molecules were prone to undergo consecutive and intramolecular reactions to form the *** general,this study revealed that the enhanced ionic strength and prolonged reaction time had the promotion effect on the lightabsorbing SOC *** implies that the aldehyde-derived aqueous-phase SOC would contribute more light-absorbing particulate matter in the industrial or populated area where inorganic ions are abundant.

关键词： Ionic strength Carbonyl-to-imine/hemiaminal Heterocyclic Brown carbon Mass spectrometry Aqueous-phase reaction

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2008年第9期51卷 1215-1230页

作者： PENG Jing YANG DongQing TANG ShiWei WANG TengJiao GAO Jun School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Department of Science and Technology Chengdu Municipal Public Security Bureau Chengdu 610017 China

The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of concepts. Through computing the inner products between concepts, it obtains the similarity between words. The new method computes the similarity of text based on the similarity of words at last. The contributions of the paper include： 1） propose a new computing formula between words; 2） propose a new text similarity computing method based on words similarity; 3） successfully use the method in the application of similarity computing of WEB news; and 4） prove the validity of the method through extensive experiments.

关键词： concept similarity similarity computing vector space inner product space

Ultrasound-Assisted Low-Density Solvent Dispersive Liquid-Liquid Extraction for the Determination of Amphetamines in Biological Samples Using Gas Chromatography-Mass Spectrometry

在线全文

学校读者我要写书评

暂无评论

Journal of Forensic Science and Medicine 2015年第2期1卷 114-118页

作者： Liang Meng Wenwen Zhang Pinjia Meng Yuxian Liu Department of Forensic Science Fujian Police CollegeFuzhou 350007 Traffic Management bureau Beijing Municipal Public Security BureauBeijing 100037 College of Forensic Science People's Public Security University of ChinaBeijing 100038 Legal Affairs Section Hunan Provincial Public Security DepartmentChangsha 410001PR China

In order to control drug crime effectively,it is necessary to develop selective analytical methods suitable for unambiguous identification and determination of drugs in illicit samples and biological matrices.A novel microextraction technique based on ultrasound-assisted low-density solvent dispersive liquid-liquid microextraction,(UA-LDS-DLLME)has been applied to the determination of four amphetamines(methamphetamine,amphetamine,3,4-methylenedioxymethamphetamine,and 3,4-methylenedioxyamphetamine)in urine samples by gas chromatography-mass *** parameters affecting extraction efficiency have been investigated and ***-LDS-DLLME used ultrasound energy to assist in the emulsification process without any disperser *** the optimized conditions,linearity was observed for all analytes in the 0.15-10 p,g/mL range with correlation coefficients(R)ranging from 0.9886 to *** recoveries of75.6-91.4%with relative standard deviations of 2.5-4.0%were *** limits of detection(S/N=3)were estimated to be in the 5-10 ng/mL *** UA-LDS-DLLME technique had the advantages of shorter extraction time,suitability for simultaneous pretreatments of batches of samples,and the higher extraction *** was successfully applied to the analysis of amphetamines in real human urine samples.

关键词： Amphetamines biological samples dispersive liquid-liquid microextraction gas chromatography-mass spectrometry ultrasonication

Drinking water quality & health risk assessment of secondary water supply systems in residential neighborhoods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第2期18卷 47-62页

作者： Yating Wei Dong Hu Chengsong Ye Heng Zhang Haoran Li Xin Yu College of the Environment&Ecology Xiamen UniversityXiamen 361102China School of public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China

Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water *** are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase *** this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential *** total,121 seasonal water samples were *** was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial *** HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and ***,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major *** samples had poor water quality and higher health risks,which called for *** further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during *** 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent *** HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in ***,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.

关键词： Drinking water quality Water quality index Health risk assessment Secondary water supply systems Heavy metals

Monodisperse silica nanoparticle suspension for developing latent blood fingermarks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Forensic Sciences Research 2020年第1期5卷 38-46页

作者： Liang Meng Yifei Ren Zhilong Zhou Congxiang Li Chen Wang Shanlin Fu Department of Forensic Science Fujian Police CollegeFuzhouChina Centre for Forensic Science University of Technology SydneyUltimoAustralia College of Forensic Science People's Public Security University of ChinaBeijingChina Narcotics Brigade Xigang District BranchDalian Municipal Public Security BureauDalianChina

Traditional fingermark developing methods are unsuitable for developing and extracting latent blood fingermarks on dark surfaces at crime scene because of their ineffectiveness or tedious operation *** the present work,an effective and simple method was developed to serve this purpose using a suspension of monodisperse silica nanoparticles(MSNs).A suspension of 0.1 g/mL of MSNs was prepared by dispersing MSNs ultrasonically into an ethanol solution containing 1.0%Tween 80 and then uniformly sprayed onto the latent blood fingermarks on black plastic *** 20 s later,ethanol was sprayed to clean the superfluous developing *** the ethanol had evaporated,the latent fin-germarks became visible as a result of the photonic crystal effect produced by the MSNs that had adsorbed to the fingermark *** developed fingermarks were then photo-graphed using a digital camera under a white or monospectral light source,revealing fine ridges and clear fingermark *** novel,simple and effective method uses the pho-tonic crystal effect of MSNs to develop latent blood fingermarks without the need for sur-face functionalization and conjugation to dye or fluorescently label *** method can detect latent blood fingermarks that have been retained on a black plastic bag surface for at least 30 *** the simplicity and effectiveness of the developed method,MSNs may be a useful alternative material for use in developing latent *** research on the topic is warranted.

关键词： Forensic sciences monodisperse silica nanoparticles photonic crystal latent blood fingermarks fingermark development dark non-porous substrate

Establishment of a blunt impact-induced brain injury model in rabbits

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Traumatology 2012年第2期15卷 100-104页

作者： LI Kui CAO Yun-xing YANG Yong-qiang YIN Zhi-yong ZHAO Hui WANG Li-jun Chongqing municipal public security bureau Chongqing 400054China

Objective： To establish an animal model to replicate the blunt impact brain injury in forensic medicine. Methods： Twenty-four New Zealand white rabbits were randomly divided into control group （n=4）, minor injury group （n：10） and severe injury group （n=10）. Based on the BIM- II Horizontal Bio-impact Machine, self-designed iron bar was used to produce blunt brain injury. Two rabbits from each injury group were randomly selected to monitor the change ofintracranial pressure （ICP） during the impact- ing process by pressure microsensors. Six hours after injury, all the rabbits were dissected to observe the injury mor- phology and underwent routine pathological examination. Results： Varying degrees of nervous system positive signs were observed in all the injured rabbits. Within 6 hours, the mortality rate was 1/10 in the minor injury group and 6/10 in the severe injury group. Morphological changes con-sisted of different levels of scalp hematoma, skull fracture, epidural hematoma, subdural hematoma, subarachnoid hemo- rrhage and brain injury. At the moment of hitting, the ICP was greater in severe injury group than in mild injury group; and within the same group, the impact side showed positive pressure while the opposite side showed negative pressure. Conclusions： Under the rigidly-controlled experimental condition, this animal model has a good reproducibility and stable results. Meanwhile, it is able to simulate the morphology of iron strike-induced injury, thus can be used to study the mechanism of blunt head injury in forensic medicine.

关键词： Brain injuries Forensic medicine Wounds, nonpenetrating Models, animal Rabbits

Isolation and NMR Study on Swainsonine from Locoweed,Astragalus strictus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2009年第1期8卷 115-120页

作者： ZHAO Bao-yu LIU Zhong-yan WANG Jian-jun SUN Li-sha WANG Zhan-xin WANG Yin-chao College of Veterinary Medicine Northwest A ＆ F University Yangling 712100 P.R.China Xi＇an municipal public security bureau Xi＇an 710000 P.R.China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 P.R.China

Locoweed is a poisonous plant wildly distributed in most area of the world and can cause livestock poisoning or death with significant economic loss. The principal responsible for its toxicity is indolizidine alkaloid swainsonine, a new potential anticancer and antiviral drug. Astragalus strictus is mainly distributed in Tibet of China and is a serious hazard to the local livestock industry. To analyze its main toxic ingredients and supply more structural information and more accurate data, swainsonine has been isolated from this plant by D101 macroporous resin and the ^1H and ^13C chemical shifts of the compound has been assigned by 1D-NMR and 2D-NMR techniques. At the same time, complete assignments of swainsonine＇s ^13C spectral signals are reported.

关键词： chemical shift assignment locoweed NMR swainsonine

Developmental Validation of the EX16+22Y System

在线全文

学校读者我要写书评

暂无评论

Journal of Forensic Science and Medicine 2020年第3期6卷 79-88页

作者： Xin Wang Weizhong Chen Jian Zhang Yang Cui Jingjing Chen Yunjie Shi Gao Wang Fayuan Li Yong Liu Ruhua Zhou Department of DNA Laboratory Institute of Criminal Science and TechnologySuzhou Municipal Public Security BureauXiangchengSuzhouChina Department of Research and Development AGCU ScienTech IncorporationHuishanWuxiChina

The EX 16+22Y system is a polymerase chain reaction(PCR)-based amplification kit that enables typing of 15 autosomal short tandem repeat(STR)loci(i.e„D3S1358,D13S317,D7S820,D16S539,TPOX,TH01,D2S133&CSF1PO,D19S433,vWA,D18S51,D21S11,D8S1179,D5S81&and FGA)and 22 widely used Y chromosome STR(Y-STR)loci(DYS391,DYS527a/b,DYS635,DYS458,DYS456,DYS385a/b,DYS43&DYS44&DYS437,DYS19,DYS576,DYS533,DYS393,DYS389I/n,DYS439,DYS392,Y_GATA_H4,DYS390,and DYS481)which contains 20 core Y-STR recommended by the Ministry of public security and *** multiplex system was designed for the simultaneous analysis of amelogenin-Y allele mutation,single-source searches,kinship(including familial searching),mixture profiles,international data sharing,and other forensic *** this study,the multiplex system was validated for sensitivity of detection,species specificity,DNA mixtures,stability,sizing precision,stutter,reproducibility,and PCR-based conditions according to the Scientific Working Group on DNA Analysis Methods developmental validation guidelines and Chinese criteria for the human fluorescent STR multiplex PCR *** results show that the EX16+22Y system is a robust and reliable amplification kit which can be used for human identification testing.

关键词： DNA typing forensic science multiplex polymerase chain reaction short tandem repeat validation