Research on uninterruptable power supply technology for auxiliary winding of electric locomotive while passing the neutral section

Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters.Powered by DC-link voltage of traction converters,the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking.Meanwhile,powered by traction transformers,the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.Design/methodology/approach–Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied.Failure reasons why previous solutions cannot be realized are analyzed.An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper.The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive.This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.Findings–This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid.Control objectives of uninterrupted power supply technology are proposed,which are no overvoltage,no overcurrent and uninterrupted power supply.Originality/value–The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section.Furthermore,this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware.

Analysis of risk factors for postpartum depression after cesarean section in women with early-onset preeclampsia

BACKGROUND Early-onset preeclampsia significantly increases maternal and fetal morbidity and mortality.Many pregnant women with early onset preeclampsia choose cesarean section as their delivery method.Although extensive research has explored the association between postpartum depression(PPD)and cesarean section,few studies have investigated the risk factors after cesarean section in women with early-onset preeclampsia.AIM To examine these risk factors through a retrospective,observational analysis of 287 women who underwent a cesarean section for early preeclampsia between June 2014 and March 2024.METHODS Participants were assessed in person during the 32nd week of pregnancy,2 days post-cesarean,and 6 weeks postpartum.According to the Edinburgh Postnatal Depression Scale(EPDS),participants who underwent cesarean section were divided into PPD(n=60)and non-PPD groups(n=227).Furthermore,PPD was diagnosed at 6 weeks postpartum according to depressive symptoms(EPDS score≥11).The demographic and clinical features of PPD were screened.Multivariate logistic regression analysis was used to identify PPD risk factors.RESULTS The prevalence of PPD was 20.9%(60/287)among the 287 women who underwent cesarean section for early-onset preeclampsia.Multivariate logistic regression analyses revealed that advanced age(age>40 years)[odds ratio(OR)=1.93,95%CI:1.31-2.82],previous preeclampsia(OR=7.15,95%CI:5.81-8.85),pre-pregnancy obesity(OR=2.42,95%CI:1.62-3.63),gestational diabetes mellitus(OR=3.52,95%CI:2.51-4.92),preexisting hypertension(OR=1.35,95%CI:1.03-1.89),PPD symptoms(EPDS≥11)at 2 days postpartum(OR=6.15,95%CI:1.32-28.35),high prenatal self-rating anxiety scale score(OR=1.13,95%CI:1.06-1.18),and pain at 6 weeks postpartum(OR=2.16,95%CI:1.28-3.66)were independently associated with PPD.CONCLUSION Risk factors for PPD after cesarean section in women with early-onset preeclampsia include advanced age(age>40 years),pre-pregnancy obesity,previous preeclampsia,gestational diabetes mellitus,preexisting hypertension,PPD symptoms(EPDS≥11)at 2 days postpartum,prenatal anxiety,and pain at 6 weeks postpartum.The early identi-fication of these factors and interventions can mitigate the risk of PPD.

Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems

This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency.

Theory of Flexural Shear, Bending and Torsion for a Thin-Walled Beam of Open Section

Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the Wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress due to bending and axial stress arising from constrained warping displacements at the fixing. The net shear stress distribution overlays the distributions from axial torsion and that from flexural shear under transverse loading. Both arise when transverse forces are displaced from the shear centre.

THEORETICAL ANALYSIS AND EXPERIMENTAL RESEARCH FOR ULTIMATE LOAD-CARRYING CAPACITY OF WEB PLATES OF Ⅰ-SECTION PLATE GIRDERS

The post buckling strength of web plate of I section plate girders is considered to resist the shear force in many other countries code for design of steel structures,while it has not been considered in the Chinese code GB J17-88.For the code revising,some important conclusions have been drawn through the theoretical analysis and experimental research of the post buckling strength of web plate of I section plate girders.

Parameter optimization of gravity density inversion based on correlation searching and the golden section algorithm

For density inversion of gravity anomaly data, once the inversion method is determined, the main factors affecting the inversion result are the inversion parameters and subdivision scheme. A set of reasonable inversion parameters and subdivision scheme can, not only improve the inversion process efficiency, but also ensure inversion result accuracy. The gravity inversion method based on correlation searching and the golden section algorithm is an effective potential field inversion method. It can be used to invert 2D and 3D physical properties with potential data observed on flat or rough surfaces. In this paper, we introduce in detail the density inversion principles based on correlation searching and the golden section algorithm. Considering that the gold section algorithm is not globally optimized. we present a heuristic method to ensure the inversion result is globally optimized. With a series of model tests, we systematically compare and analyze the inversion result efficiency and accuracy with different parameters. Based on the model test results, we conclude the selection principles for each inversion parameter with which the inversion accuracy can be obviously improved.

Value of section plane,MPR,and 3D-CTVR techniques in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane

Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane.Methods: Here, 17 cases of otosclerosis and 22 cases of ossicular chain deformity were selected. All patients had normal external ear canals,intact tympanic membranes, conductive hearing loss, type A tympanograms, and negative Gelle's tests. The respective radiological reports of the status of the ossicles via 3 protocols were compared to surgical findings. The quantitative assessments of the representation of different segments of the ossicular chain were based on a 3-point scoring system.Results: MPR and CTVR imaging both showed the integrity of whole ossicular chain well. MPR and CTVR imaging were found to be superior to section planes with respect to showing the superstructure of the stapes and malformations(P > 0.05).Conclusion: CTVR and MPR imaging were found to be better able to show the whole ossicular chain in the conductive hearing loss with normal tympanic membranes. Furthermore, the use of these techniques can have profound contributive value in the differential diagnosis of otosclerosis and ossicular chain absence or malformation.

Diagnosing early scar pregnancy in the lower uterine segment after cesarean section by intracavitary ultrasound

BACKGROUND Early scar pregnancy(CSP)in the lower uterine segment after cesarean section is a type of ectopic pregnancy that can cause major complications if left untreated.Transabdominal ultrasound is a common procedure but is influenced by external factors.Thus,intracavitary ultrasound may have better diagnostic efficiency for CSP.AIM To assess the value of intracavitary ultrasound for diagnosing CSP in the lower uterine segment after cesarean section.METHODS Patients diagnosed with CSP in our hospital from October 2019 to April 2021 were recruited.Transabdominal and intracavitary ultrasound examinations were performed to compare the diagnostic differences for CSP and its types.RESULTS Sixty-three patients were diagnosed during the study period.The diagnostic accuracy for CSP was higher in intracavitary ultrasound(96.83%)than in transabdominal ultrasound(84.13%)(P<0.05).The missed diagnosis and misdiagnosis rates did not differ among the ultrasound types(intra:0.00%and 3.17%;trans:4.76%and 11.11%,respectively;P>0.05).For the diagnostic rates for the CSP types,the rates for gestational sac(100.00%vs 90.48%),heterogeneous mass(93.75%vs 75.00%),and part of the uterine cavity(80.00%vs 60.00%)were higher in intracavitary ultrasound than in transabdominal ultrasound,but the difference was not statistically significant(P>0.05).For gestational sac CSP patients,intracavitary ultrasound showed that the gestational sac was located in the lower uterine segment scar with abundant peripheral blood flow;the distance between the gestational sac and the serosal layer was 2.42±0.50 cm.Intracavitary ultrasound for heterogeneous mass CSP patients indicated that the mass mainly occurred in the lower anterior uterine wall,protruding into the bladder,and was surrounded by abundant internal and peripheral blood flow;the distance between the mass and serosal layer was 1.79±0.30 cm.For CSP type partly located in the uterine cavity,the gestational sac was partly located in the lower uterine cavity and partly in the scar with abundant internal and peripheral blood flow;the distance between the gestational sac and the serosal layer was 2.29±0.28 cm.CONCLUSION Intracavitary ultrasound had a higher diagnostic accuracy and application value for diagnosing CSP than transabdominal ultrasound,with reduced risk of missed diagnoses and misdiagnosis,thereby preventing delayed treatment.

Characterization of Iron Grains near the P/T Boundary in the Meishan Section of China

The Meishan section of China has been confirmed as the ＂Global Stratotype Section and Point＂ of the P/T boundary. In the section, the authors found several types of iron grains, including pyrite, pure iron grains and goethite. From the research of macro minerals, it is easy to find that the grains rich in iron appear from the bottom of the event layer of the section. In other words, it is probably residue of the geochemical catastrophe of that time. Therefore, it is important to trace the source of these iron grains and their relationships, which probably provides evidence for volcanic eruption or impact-volcanoes and has directive significance to the crisis during the P/T transitional period. Through the study of the characterization and relationships of these iron grains, the authors make a preliminary discussion on the P/T mass extinction.

Clinical Observation on Termination of Early Pregnancy of 213 Cases after Caesarian Section with Repeated Use of Mifepristone and Misoprostol

Objective To investigate the efficacy and safety in women after caesarian section for termination of early pregnancies by treatment, or repeated treatment with mifepristone and misoprostol. Subjects and Methods A total of 213 pregnant women with amenorrhea of 34~69 d after caesarian section who asked for medical abortion were recruited, including 63 cases undergoing their second medical abortion. A total amount of mifeprisstone of 150 mg given in separate doses (25 mg×4 and 50 mg at the first time) was administered orally within 3 d, followed by misoprostol of 0.6 mg orally in the morning of d 3. Results The complete abortion rate was 92.5%, incomplete abortion was 4.7% and failure was 2.8%. Conclusion The sequential use of mifepristone and misoprostol could be successfully and repeatedly used for induced abortion in those women with a caesarian section history. Its efficacy was similar to that for ordinary population. Its safety and effectiveness were satisfactory.

Reliable clinical and sonographic findings in the diagnosis of abdominal wall endometriosis near cesarean section scar

AIM: To highlight sonographic and clinical characteristics of scar endometrioma with special emphasis on size-related features. METHODS: Thirty women (mean age 30.6 years, range 20-42 years) with 33 scar endometriomas (mean diameter 27.1 mm, range 7-60 mm) were consecutively studied by Sonography and Color Doppler examination prior to surgery. Pathological examination was available in all cases. RESULTS: The most frequent (24 of 33 nodules, 74%) sonographic B-mode aspect of endometrioma was that of an inhomogenously hypoechoic roundish nodule with fibrotic changes (in the form of hyperechoic spots or strands), a peripheral inflammatory hyperechoic ring, spiculated margins and a single vascular pedicle entering the mass at the periphery. On average, 1.6 cesarean sections were recorded per patient (range 1-3). The median interval between the last cesarean section and admission to hospital was 36 mo (range 12-120 mo) and the median duration of symptoms before admission was 25.7 mo (range 0.5-80 mo). 13 patients had 13 large endometriomas (≥ 30 mm) with a mean lesion diameter of 41.3 ± 9.02 mm (range 30-60 mm). Seventeen women had 20 small endometriomas with a mean lesion size of 18.2 ± 5.17 mm (range 7-26 mm). The mean interval between the last cesarean section and admission to hospital (66.0 mo vs 39.6 mo, P < 0.01) and the mean duration of symptoms before admission (43.0 mo vs 17.4 mo, P < 0.01) were significantly longer in patients with large endometriomas; in addition, a statistically significant higher percentage of patients with large implants had undergone previous inconclusive diagnostic examinations, including either computed tomography/magnetic resonance imaging/fine needle biopsy/laparoscopy (38.4% vs 0%, P < 0.05). On sonography, large endometriomas showed frequent cystic portions and fistulous tracts (P < 0.02), loss of round/oval shape (P < 0.04) along with increased vascularity (P < 0.04). CONCLUSION: Endometrioma near cesarean section scar is an often neglected disease, but knowledge of its clinical and sonographic findings may prevent a delay in diagnosis that typically occurs in patients with larger (≥ 3 cm) endometriomas.

Accuracy of Measuring Axillary Temperature Using Mercury in Glass Thermometers in Children under Five Years: A Cross Sectional Observational Study

Background: Measuring axillary temperature with mercury in glass thermometers is continued in clinical practice though there are many limitations. This is mainly due to convenience and cost. This study was conducted to ascertain the accuracy of measuring axillary temperature with mercury thermometers in preschool children. Methods: Axillary temperature was measured in 250 preschool children using standardized mercury thermometers. Time taken to record the final temperature and its correlates were assessed. Results: Time taken to record the final temperature extended up to six minutes. This duration varied according to age, body mass index and body temperature, but a significant variation was noted only with age. Conclusions: Measuring axillary temperature with mercury thermometers is subjected to error. They need to be replaced with suitable alternatives.

Association between clustering of cardiovascular risk factors and resting heart rate in Chinese population:a cross-sectional study

BACKGROUND Epidemiologic studies have explored the association between a single cardiovascular risk factor(CVRF)and resting heart rate(RHR),but the research on the relation of multiple risk factors with RHR remains scarce.This study aimed to explore the associations between CVRFs clustering and the risk of elevated RHR.METHODS In this cross-sectional study,adults aged 35-75 years from 31 provinces were recruited by the China PEACE Million Persons Projects from September 2015 to August 2020.We focused on seven risk factors:hypertension,diabetes mellitus,dyslipidemia,obesity,smoking,alcohol use,and low physical activity.Multivariate logistic regression was used to calculate odds ratios(OR)for elevated RHR(>80 beats/min).RESULTS Among 1,045,405 participants,the mean age was 55.67±9.86 years,and 60.4%of participants were women.The OR(95%CI)for elevated RHR for the groups with 1,2,3,4 and≥5 risk factor were 1.11(1.08-1.13),1.36(1.33-1.39),1.68(1.64-1.72),2.01(1.96-2.07)and 2.58(2.50-2.67),respectively(Ptrend<0.001).The association between the CVRFs clustering number and elevated RHR was much more pronounced in young males than in other age-sex subgroups.Clusters comprising more metabolic risk factors were associated with a higher risk of elevated RHR than those comprising more behavioral risk factors.CONCLUSIONS There was a significant positive association between the CVRFs clustering number and the risk of elevated RHR,particularly in young males.Compared clusters comprising more behavioral risk factors,clusters comprising more metabolic risk factors were associated with a higher risk of elevated RHR.RHR may serve as an indicator of the cumulative effect of multiple risk factors.

Saddle-Dolomite-Bearing Fracture Fillings and Records of Hot Brine Activity in the Jialingjiang Formation,Libixia Section,Hechuan Area of Chongqing City

Most vein minerals deposited in fractures of the Jialingjiang Formation from Libixia section, Hechan area include a large amount of saddle dolomite and accompanying celestite, calcite and fluorite. This study analyzed the nature, source, evolution of the fluids by plane-light petrography, fluid-inclusion methods, cathodoluminescence images, and stable isotopic compositions. The homogenization temperatures of two-phase aqueous fluid inclusions in dolomite range between 100 and 270℃. Combined with the jlSO data, it is suggested that the fluid responsible for the precipitation of fracture fillings have δ18O values between 10%o and 18‰ （relative to SMOW）. The saddle dolomite and the accompanying minerals were the result of activity of dense brines at elevated temperatures. Moreover, analysis shows that the fluid was derived from a mixture of marine-derived brine and deeper circulating flow. This fluid was enriched in Sr during diagenesis and formed celestite in fracture and for regional mineralization. Dissolution of saddle dolomite was attributed to the cooling of Mg/Ca-decreased fluids, which may relate to a leaching of gypsum to celestite in surrounding carbonates.

Comparative Study between Intraoperative Frozen Section and Scrape Smear Cytology in the Diagnosis of Ovarian Neoplasm

Objective: The aim of this work is to compare between intraoperative frozen section and scrape smear cytology in the diagnosis of ovarian neoplasm. Method: This study was performed between March 2011 and March 2012, on 50 patients presented with ovarian mass. Gross examination of the tumor removed was done by inspection and palpation. The specimen was then cut with a sharp knife into two halves. The area was scraped with a sharp scalpel or the end of a glass slide, depending upon the type of tissue. A semifluid drop thus obtained was spread over a glass slide. One to four slides per case were taken from different representative areas. The slides were labelled and immediately put into 95% ethyl alcohol and stained with hematoxylin-eosin. The specimens were then fixed in formalin. Paraffin blocks of the sections were processed in the routine way and sections were stained with hematoxylin and eosin (H and E). Assessment of the overall accuracy of the intraoperative diagnosis was classified as concordant or discordant. Results: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of scraping technique in the diagnosis of benign ovarian masses were 100%, 95.2%, 96.7%, 100% and 98% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of scraping technique in the diagnosis of border line ovarian masses were 100%, 93.4%, 25%, 100% and 94% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of scraping technique in the diagnosis of malignant ovarian masses were 80%, 100%, 100%, 88.2% and 92% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of frozen section in the diagnosis of benign ovarian masses were 100%, 100%, 100%, 100% and 100% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of frozen section in the diagnosis of borderline ovarian masses were 100%, 95.9%, 33.3%, 100% and 96% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of frozen section in the diagnosis of malignant ovarian masses were 90%, 100%, 100%, 93.8% and 96% respectively. Conclusion: Frozen section is more accurate than smear preparations in the intraoperative assessment of ovarian tumors in this study. However, the cytology preparations were helpful in supporting the histological diagnoses, and in some cases, provided additional useful information. Thus, cytology has a complementary role to frozen section in the intraoperative assessment of ovarian lesions. At the centers where the facilities of frozen section are not available, intraoperative scrape cytology is a useful tool for intraoperative diagnosis of tumor.

Photo-detachment cross section of H- near two parallel interfaces

The photo-detachment cross section of H^- near two parallel elastic interfaces is derived and calculated by using the closed orbit theory. The photo-detachment cross section of H^- near two interfaces is shown to exhibit multi-periodic oscillations when the distance between the H^- and the interface is varied. Each peak in the Fourier transformed photo-detachment cross section corresponds to the length of a closed orbit, which is quite similar to the case of atomic spontaneous emissions in a dielectric slab. This study provides a new understanding of the photo=detachment process of H^- in the presence of interfaces.

Numerical simulation research on response characteristics of surrounding rock for deep super-large section chamber under dynamic and static combined loading condition

The stability control of surrounding rock for large or super-large section chamber is a difficult technical problem in deep mining condition.Based on the in-site geological conditions of Longgu coal mine,this paper used the dynamic module of FLAC3D to study the response characteristics of deep super-large section chamber under dynamic and static combined loading condition.Results showed that under the static loading condition,the maximum vertical stress,deformation and failure range are large,where the stress concentration coefficient is 1.64.The maximum roof-to-floor and two-sides deformations are 54.6 mm and 53.1 mm,respectively.Then,under the dynamic and static combined loading condition:(1)The influence of dynamic load frequency on the two-sides is more obvious;(2)The dynamic load amplitude has the greatest influence on the stress concentration degree,and the plastic failure tends to develop to the deeper;(3)With the dynamic load source distance increase,the response of surrounding rock is gradually attenuated.On this basis,empirical equations for each dynamic load conditions were obtained by using regression analysis method,and all correlation coefficients are greater than 0.99.This research provided reference for the supporting design of deep super-large section chamber under same or similar conditions.

Progress of photonuclear cross sections for medical radioisotope production at the SLEGS energy domain

Photonuclear reactions using a laser Compton scattering(LCS)gamma source provide a new method for producing radioisotopes for medical applications.Compared with the conventional method,this method has the advantages of a high specific activity and less heat.Initiated by the Shanghai Laser Electron Gamma Source(SLEGS),we conducted a survey of potential photonuclear reactions,(γ,n),(γ,p),and(γ,γ')whose cross sections can be measured at SLEGS by summarising the experimental progress.In general,the data are rare and occasionally inconsistent.Therefore,theoretical calculations are often used to evaluate the production of medical radioisotopes.Subsequently,we verified the model uncertainties of the widely used reaction code TALYS-1.96,using the experimental data of the^(100)Mo(γ,n)^(99)Mo,^(65)Cu(γ,n)^(64)Cu,and^(68)Zn(γ,p)^(67)Cu reactions.

COVID-19 mental health care toolkit:an international collaborative effort by Early Career Psychiatrists section

The collaborative effort of an international research team from the Early Career Psychiatrists section of the World Psychiatry Association has brought about an easy-to-use,quick and stepwise mental health care toolkit for the identification and appropriate referral of those in need of mental health care during the pandemic.This simple guide can be applied in the general outpatient setting and is catered for all healthcare professionals,regardless of their expertise within the mental health field with minimal training.It is our hope that by incorporating this toolkit into our daily clinical care during the pandemic for high-risk patients and patients with non-specific complaints,we will be able to bridge the mental health gap present in our society.

The Research of Urban Rail Transit Sectional Passenger Flow Prediction Method

This paper studies the short-term prediction methods of sectional passenger flow, and selects BP neural network combined with the characteristics of sectional passenger flow itself. With a case study, we design three different schemes. We use Matlab to realize the prediction of the sectional passenger flow of the Beijing subway Line 2 and make comparative analysis. The empirical research shows that combining data characteristics of sectional passenger flow with the BP neural network have good prediction accuracy.