An Analysis of Supply Chain Environment in Great Wall Motor Based on Life-Cycle Assessment

Great Wall Motor(GWM),a leading automotive manufacturer,places a strong emphasis on environmental sustainability and social responsibility.The company focuses on comprehensively evaluating and enhancing its supply chain to align with these objectives.This evaluation spans the entire product life cycle,encompassing design,manufacturing,packaging,distribution,usage,and recycling and disposal processes.Key areas of focus include optimizing raw material selection,improving product recyclability,reducing energy consumption and waste emissions,and minimizing carbon emissions during transportation.Through these endeavors,GWM not only enhances its environmental performance by reducing carbon emissions and resource consumption but also bolsters its brand image and competitiveness in the market.GWM’s dedication to environmental innovation and technological leadership serves as a driving force behind sustainable development and social responsibility within the industry.

Sequence Stratigraphy and Sedimentary Facies of Feixianguan Formation in the Kaijiang-Liangping Area of Sichuan Basin, China

The Feixianguan formation in the Kaijiang-Liangping basin has been the focus of extensive research on multiple aspects. Based on field survey, core observation, laboratory analysis and seismic data interpretation, the sequence stratigraphy and sedimentary facies of the Kaijiang-Liangping area are studied. Four sequence boundaries and three maximum flooding surfaces of the Feixianguan formation are detected in this area. Three third-order sequences are identified as first sequence (SQ1), the second sequence (SQ2), and the third sequence (SQ3) in which SQ1 corresponds to the member 1 of the Feixianguan formation, SQ2 corresponds to the member 2, and SQ3 corresponds to the member 3 and member 4. Member 1, 2, 3 and 4 are lithologic sections divided by predecessors. On the basis of this sequence division and their sedimentary marks, the facies of the Feixianguan formation can be divided into open platform and evaporate platform categories. The open platform is composed of three subfacies identified as platform bank or basin marginal bank, interbank, and platform basin. Thus, a sedimentary evolution model is established. According to the sedimentary and seismic characteristics of the Kaijiang-Liangping area, we determine that two oolitic bank models, the aggradation model and the progradation model, are developed in this area. The aggradation model is developed in the Longgang region, which includes the basin marginal bank as a favorable exploring zone. The progradation model is developed in the Jiulongshan and Longhui areas, besides the basin marginal bank, the favorable exploration zones also include the oolitic bank developing areas of the inner basin.

MTT Detection of the Toxicity on CdTe Quantum Dots

Objective: The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with ZnS core quantum dots and CdTe quantum dots modified with Thioglycolic acid or Cysteine functional group (TGA-CdTe, TGA-CdTe/ZnS, Cys-CdTe, Cys-CdTe/ZnS) on Caco-2 cell proliferation. Methods: We studied the effect of cell inhibition with ZnS core QDs and CdTe QDs modified with functional group on Caco-2 cell proliferation by MTT assay at 0, 12.5, 25, 50, 100 μg/ml and 6, 24, 48 h. Result: Our results showed that all QDs have inhibited cell proliferation and reached maximum 79.21%. The inhibition rate of Cys-modified QDs increased with the increase of concentration and reached maximum 66.72%. The inhibition rate of TGA-modified QDs increased with the increase of time. The ratios of Cys-modified to TGA-modified were less than 1 at all concentrations and three exposure times (P ≤ 0.01). The average ratios of Cys-CdTe/ZnS to Cys-CdTe reached 1.11 only for 48 h (P ≤ 0.05). The ratios of TGA-CdTe/ZnS to TGA-CdTe were closed to 1 at all concentrations and exposure times. Conclusion: The regularity of QDs modified with functional group is that inhibition of TGA-modified higher than Cys-modified. Inhibition exhibited dose-dependent for Cys-modified while exhibited time-dependent for TGA-modified. The regularity of CdTe-QDs with ZnS or not is that the inhibition of Cys-CdTe/ZnS was higher than Cys-CdTe while TGA-CdTe/ZnS and TGA-CdTe were consistent.

DOA estimation method for wideband signals by sparse recovery in frequency domain

The traditional super-resolution direction finding methods based on sparse recovery need to divide the estimation space into several discrete angle grids, which will bring the final result some error. To this problem, a novel method for wideband signals by sparse recovery in the frequency domain is proposed.The optimization functions are found and solved by the received data at every frequency, on this basis, the sparse support set is obtained, then the direction of arrival(DOA) is acquired by integrating the information of all frequency bins, and the initial signal can also be recovered. This method avoids the error caused by sparse recovery methods based on grid division, and the degree of freedom is also expanded by array transformation, especially it has a preferable performance under the circumstances of a small number of snapshots and a low signal to noise ratio(SNR).

DOA estimation method for wideband signals by block sparse reconstruction

For the direction of arrival(DOA) estimation,traditional sparse reconstruction methods for wideband signals usually need many iteration times.For this problem,a new method for two-dimensional wideband signals based on block sparse reconstruction is proposed.First,a prolate spheroidal wave function(PSWF) is used to fit the wideband signals,then the block sparse reconstruction technology is employed for DOA estimation.The proposed method uses orthogonalization to choose the matching atoms,ensuring that the residual components correspond to the minimum absolute value.Meanwhile,the vectors obtained by iteration are back-disposed according to the corresponding atomic matching rules,so the extra atoms are abandoned in the course of iteration,and the residual components of current iteration are reduced.Thus the original sparse signals are reconstructed.The proposed method reduces iteration times comparing with the traditional reconstruction methods,and the estimation precision is better than the classical two-sided correlation transformation(TCT)algorithm when the snapshot is small or the signal-to-noise ratio(SNR) is low.

Mechanical Properties of a Eucalyptus-Based Oriented Oblique Strand Lumber for Structural Applications

Wood and wood-based composite materials have gained increasing attention in the sustainable building industry because of their renewability and environmental friendliness.Oriented oblique strand lumber(Eucalyptus Strand Wood,ESWood),which is manufactured from fast-growing small diameter eucalyptus wood(Eucalyptus urophylla×E.grandis),is introduced in this paper.Small clear specimen tests were conducted to determine the mechanical properties of ESWood material while full-scale component tests were performed to observe the structural performance of ESWood beams.A comparison of mechanical properties of ESWood with other wood/bamboo-based materials is then reported.From the results presented herein,it appears that the strength and stiffness properties of ESWood are affected by grain directionality and glued layers.However,it still has preferable mechanical properties as a building material,which is comparable or superior to those of other engineered wood/bamboo-based products(e.g.,Sitka spruce,LVL,OSL,Glulam,and Glubam).Furthermore,results from full-scale component tests show the stable mechanical performance of beams made by ESWood.This study makes a significant contribution to a potential utilization of fast-growing eucalyptus for general use in construction,and the presented mechanical tests results can serve as a fundamental data for more applications of ESWood in practical engineering.

Template Protection Based on Chaotic Map for Face Recognition

With the widespread deployment of biometric recognition,personal data security and privacy are attracted more and more attentions.A crucial privacy issue is how to ensure the security of user template.This paper proposes a novel template protection algorithm for face recognition based on chaotic map.Each face template is corresponding to different chaotic sequence produced by system master key and user identification number.The order of chaotic sequence controls the substitution index of face template.Experiment results on facial FERET database show that our algorithm can significantly improve the recognition performance and ensure the security of face template.

Research on Interactive Simulation Experiment Platform and Remote Simulation System Under Web Environment

This paper brings forward a method of experimental teaching reform of universities and colleges,which establishes an interactive simulation experiment platform with MATLAB simulation software.The platform uses visual man-machine interface,which avoids a lot of programming and debugging work,and improves students’learning enthusiasm.Simultaneously,it implements remote simulation based on JAVA under web environment,which is convenient for network teaching,and improves flexibility and practicability of the simulation experiment platform.

Exploration on the Application of Microlecture in Presentation-Assimilation-Discussion Class

As the rapid development of information technology represented by mobile internet,internet of things,social computing,society has entered the age of big data,information technology and education teaching are also merged gradually,microlecture as a new application of education and teaching took the wide attention of scholars.This paper analyzes the disadvantages of PAD class and takes microlecture to apply to two stage of PAD class.

适用于国土空间规划和景观设计行业的整体主义研究倡议

当下,在城乡规划和景观设计领域存在一大困惑与悖论,即相关跨学科研究在整合其他学科的科研路径和研究方法的过程中,逐渐失去了与规划设计实践的联系。面对这一困扰,本文从规划设计实践的整体性决策需求与现代科研的还原主义体系之间的差异入手,提出强化整体主义研究的倡议,并建议强化“实践经验的规律提炼”“系统科学的整体探究”及“跨学科的知识集成”来辅助未来国土空间规划和景观设计实践。

社交媒体文本数据分析方法对比与适用性研究:以北京市城市公园感知为例

互联网科技和媒体的蓬勃发展产生了大量社交媒体数据,基于自发评论文本进行社会感知分析逐渐成为研究热点,也开始被应用于城市公园使用情况和情感认知的研究中。鉴于现有研究大都应用单一的文本分析方法,本研究尝试开展社交媒体文本数据分析方法的对比研究,并揭示其在公园感知研究中的优缺点和适用性。研究选择在相关领域广泛应用的词典模型和LDA模型,以大众点评网站上北京10座城市公园的点评文本为研究数据,分别从单个公园和公园整体使用感知两个层面进行文本分析,并对比分析感知主题的分类结果。结果表明:词典模型更有利于在公园间进行横向对比分析;LDA模型则可以直观显示公园特色和游客感知偏好;综合运用两种模型可优化公园感知评估。两种方法揭示了北京城市公园游客对公园的关注主要集中于社交活动的需求、自然景观带来的视觉审美需求,以及交通设施状况和城市公园消费情况。本研究既可为社交媒体文本分析方法的选择和使用提供优化建议,又可为公园建设与管理改进提供依据与指导。

类液晶作为高性能有机场效应晶体管的有源层

高载流子迁移率和器件性能的一致性对于有机场效应晶体管在阵列和集成电路上的应用至关重要.然而,同时具备高性能和小批间差的方法当前仍然是个挑战.本论文在原子力显微镜和偏振荧光显微镜表征的基础上,报道了在PTCDI-C1_(3)分子模板上生长具有大晶畴的dif-TES-ADT类液晶状薄膜的方法.我们进一步将所获得的薄膜用作有机场效应晶体管的载流子传输通道,其饱和载流子迁移率高达1.62±0.26 cm^(2)V^(-1)s^(-1).更重要的是,在重复三个批次之间,每次50个器件的迁移率批间差仅为16%.这一发现为设计材料和器件结构以同时实现高载流子迁移率和器件均匀性提供了一种新思路.

Dual-targeted nanoformulation with Janus structure for synergistic enhancement of sonodynamic therapy and chemotherapy

The accurate delivery of nanoparticles and organic small molecule drugs remains a serious challenge in nanoparticle-based tumor therapy.Dual-targeted therapy combining tumor cell targeting and organelle targeting is an effective solution.Here,an anticancer nanoformulation accurate delivery system was prepared using hyaluronic acid (HA) targeting CD44 receptors on the surface of tumor cells and IR780iodine (IR780) targeting mitochondrial for delivery.The system is based on an ultra-small Janus structured inorganic sensitizer TiO_(2-x)@NaGdF_(4) nanoparticles (TN NPs) prepared by one-step pyrolysis,further loaded with organic small molecule acoustic sensitizer IR780 and mitochondrial hexokinase Ⅱ inhibitor lonidamine (LND),followed by encapsulation of HA.Ultra-small size nanoparticles exhibit strong tissue penetration,tumor inhibition and in vivo metabolism.Under ultrasound radiation,TN NPs and IR780could produce a synergistic effect,effectively increased the efficiency of reactive oxygen species (ROS)production.Meanwhile,the released IR780 could smoothly target the mitochondria,and the ROS produced by IR780 can destroy the mitochondrial structure and disrupt the mitochondrial respiration.LND could inhibit the energy metabolism of tumor cells by reducing the activity of hexokinase Ⅱ (HK Ⅱ),which further accelerates the process of apoptosis.Furthermore,since the Janus structure allows the integration of multifunctional components into a single system,TN NPs can not only serve as an acoustic sensitizer to generate ROS,but the Gd element contained can also act as the nuclear magnetic resonance (MR)imaging contrast agent,suggesting that the nanoformulation can enable imaging-guided diagnosis and therapy.In conclusion,a new scheme to enhance sonodynamic therapy (SDT) and chemotherapy synergistically is proposed here based on ultra-small dual-targeted nanoformulation with Janus structure in the ultrasound radiation environment.

Frequency of Food Consumption Among Students Aged 8–15 Years—China,2019 and 2021

A balanced consumption of various types of food items plays a crucial role in students’physical and intellectual development,providing the foundation for their lifelong health(1).In recent years,the living standards in China have improved,leading to a steady improvement in the intake of various foods among Chinese students(2).However,uneven socioeconomic development and differing natural environments may lead to disparities in food consumption between rural and urban students(3).The prevalence of malnutrition among rural students has decreased but remains higher than among urban students(4).Furthermore,consumption of various healthy foods increased during the coronavirus disease 2019(COVID-19)pandemic as a means to boost immunity and promote health(5).

Two-Dimensional Code Transmission System Based on Side Channel Feedback

Two-dimensional code technology is widely used in all walks of life due to its high reliability,large information capacity and relative security of infor-mation.As the carrier of data transmission,two-dimensional code has become a new form of nearfield communication,and mainly used for theflow of docu-ments.The rapid spread of smart devices with cameras has further broadened the use of two-dimensional code.The combination of smartphones and two-dimensional code eliminates the dependence on special physical isolation devices and reduces transmission costs.In this paper,a two-dimensional code transmission system based on side channel is designed,which transmits confidential informa-tion through the visual main channel of two-dimensional code and retransmits feedback information through the acoustic side channel.This paper verifies the impact of QR code capacity on data integrity and improvesfile transfer integrity.

DP-ASSGD: Differential Privacy Protection Based on Stochastic Gradient Descent Optimization

Recently,differential privacy algorithms based on deep learning have become increasingly mature.Previous studies provide privacy mostly by adding differential privacy noise to the gradient,but it will reduce the accuracy,and it is difficult to balance privacy and accuracy.In this paper,the DP-ASSGD algo-rithm is proposed to counterpoise privacy and accuracy.The convergence speed is improved,the number of optimized iterations is decreased,and the privacy loss is significantly reduced.On the other hand,by using the postprocessing immunity characteristics of the differential privacy model,the Laplace smoothing mecha-nism is added to make the training process more stable and the generalization ability stronger.The experiment uses the MNIST dataset,with the same privacy budget,and compared with the existing differential privacy algorithms,the accu-racy is improved by 1.8%on average.When achieving the same accuracy,the DP-ASSGD algorithm consumes less privacy budget.

生态实践中的传承与创新--中国城市科学研究会景观学与美丽中国建设专业委员会座谈会纪实

2018年1月21日,中国城市科学研究会景观学与美丽中国建设专业委员会座谈会于北京大学建筑与景观设计学院举办。来自景观、生态、水利、规划等领域的30余位学者、设计师、教育者及其他从业人士参加了会议,并围绕美丽中国建设、生态文明建设、景观设计学科建设、行业融合等议题展开讨论。座谈会最终达成共识,提出了跨界生态实践的迫切性和必要性,同时探讨了在教育和实践层面跨界的难点与问题——不同行业的优势、职责以及在"跨界"中的作用尚不明确,学科教育也未能很好地构建并明晰自身的核心竞争力——呼吁应积极促进学科与行业融合,使其适应当代需求。

手性共价有机框架材料的研究进展与应用

共价有机框架材料(covalent organic frameworks, COFs)是一类是由各种有机小分子单体通过共价键有序连接而成的有机多孔材料.手性是一种在自然界中普遍存在的现象,手性化合物在医学、药学、农业等方面有重要应用.近几年,手性COFs引起了广大科研工作者的注意.手性COFs由于具有永久多孔、隧道型孔道、结构可预测、结构稳定、可循环利用等特点,在手性催化、手性分离等领域具有广泛的潜在应用.合成手性COFs材料的一种方案是通过各种不同的手性构筑单元直接连接而成,所以通过设计不同结构的手性构筑单元和合成具有功能性基团的手性单体可以得到结构多样的手性COFs材料.手性COFs材料的另一种合成方案是利用后修饰的方法将金属粒子或者有机小分子修饰到手性COFs骨架上从而对结构进行功能性调控.

Melt polymerization synthesis of a class of robust self-shaped olefin-linked COF foams as high-efficiency separators

The practical applications of crystalline porous materials toward industrial separations require shaping them into robust monoliths(e.g., foams). The current methods are often complicated, environmentally unfriendly, and unscalable, significantly hampering their practical application. Herein, we report a scalable, facile “one-step thermomolding” method to fabricate a class of hierarchically olefin-linked covalent organic framework(COF) foams via melt polymerization. The obtained pure COF foams possess higher crystallinity and porosity than literature, good moldability, and processability, greatly benefiting their practical applications(e.g., efficient oil-water separation with 99% removal efficiency and >100 cycle reusability). Moreover, a COF exhibiting the smallest(0.58 nm) eclipsed stacking pore among all 2-dimensional COFs with neutral skeletons is first fabricated via this protocol, demonstrating good C2 H2 purification performance and recyclability, surpassing the current benchmark materials. We believe that this facile fabrication strategy can promote access to a broad diversity of new COF foams and enlighten further avenues for green routes to large-scale synthesis and usage of COFs.

Thermally rearranged covalent organic framework with flame-retardancy as a high safety Li-ion solid electrolyte

Solid polymer electrolytes have demonstrated high promise to solve the safety problems caused by conventional liquid electrolytes in lithium ion batteries.However,the inherent flammability of most polymer electrolyte materials remains unresolved,hence hindering their further industrial application.Addressing this challenge,we designed and constructed a thermal-responsive imide-linked covalent organic framework(COF)bearing ortho-positioned hydroxy groups as precursors,which can conduct a thermal rearrangement to transform into a highly crystalline and robust benzoxazole-linked COF upon heating.Benefiting from the release of carbon dioxide through thermal rearrangement reaction,this COF platform exhibited excellent flame retardant properties.By contrast,classic COFs(e.g.,boronate ester,imine,olefin,imide linked)were all flammable.Moreover,incorpo-rating polyethylene glycol and Li salt into the COF channels can produce solid polymer electrolytes with outstanding flame retardancy,high ionic conductivity(6.42×10^(-4) S cm^(-1))and a high lithium-ion transference number of 0.95.This thermal rearrangement strategy not only opens a new route for the fabrication of ultrastable COFs,but also provides promising perspectives to designing flame-retardant materials for energy-related applications.