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An improved social force model (ISFM)-based crowd evacuation simulation method in virtual reality with a subway fire as a case study

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International Journal of Digital Earth 2023年第1期16卷 1186-1204页

作者： Jinbin Zhang Jun Zhu Pei Dang Jianlin Wu Yuxuan Zhou weilian Li Lin Fu Yukun Guo Jigang You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany School of Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China

Crowd evacuation simulation using virtual reality(VR)is significant for digital emergency response ***,existing evacuation simulation studies suffer from poor adaptation to complex environments,inefficient evacuations,and poor simulation effects and do not fully consider the impacts of specific disaster environments on crowd *** more realistically express the crowd evacuation results obtained under the influence offire environments and the subjective consciousness of pedestrians in subway stations,we designed a dynamic pedestrian evacuation path planning method under multiple constraints,analysed the influences of an‘environmental role’and a‘subjective initiative’on crowd evacuation,established an improved social force model(ISFM)-based crowd evacuation simulation method in VR,developed a prototype system and conducted experimental *** experimental results show that the crowd evacuation time of the ISFM is affected by the disaster *** simulation experiments without disaster scenarios,the improved model’s crowd evacuation efficiency improved by averages of 12.53%and 15.37%over the commercial Pathfinder software and the original social force model,*** method described herein can effectively support real-time VR crowd evacuation simulation under multiexit and multifloor conditions and can provide technical support for emergency evacuation learning and management decision analyses involving subwayfires.

关键词： Subway stationfire improved social force model crowd evacuation simulation virtual reality path planning

Lacticaseibacillus paracasei K56 inhibits lipid accumulation in adipocytes by promoting lipolysis

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Food Science and Human Wellness 2023年

作者： Silu Wang Jinxing Li Wei-Hsien Liu Niya Li Huijing Liang weilian Hung Qiuyue Jiang Ruyue Cheng Xi Shen Fang he Department of Nutrition and Food Hygiene， West China School of Public health and West China Fourth Hospital， Sichuan University Inner Mongolia Yili Industrial Group Co.， Ltd

Probiotics crosstalk immunity to improve host glycolipid metabolism， which is a new strategy for obesity. This study aimed to explore the functions of Lacticaseibacillus paracasei K56 (K56)， in regulating the lipid metabolism of adipocytes and its immune regulation *** co-cultured RAW264.7 macrophages with K56， and the K56-stimulated RAW264.7-conditioned medium (K56-CM) was collected and treated with 3T3-L1 pre-adipocytes. The expression of lipid metabolism-related markers of adipocytes， and the content of cytokines in CMs were detected. The results demonstrated that K56-CM promoted the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ)， CCAAT/enhancer binding protein α (C/EBPα)， and other adipogenesis-related markers， which resulted in the upregulation of lipolysis markers， such as hormone-sensitive lipase (HSL)， adipose triglyceride lipase (ATGL). The activation of lipolysis enhanced the expression of fatty acid β-oxidation-related and mitochondrial biogenesis-related markers and reduced lipid accumulation in adipocytes. The glycolipid metabolism pattern of K56 may be due to its immunomodulatory characteristics， which stimulated macrophages to secrete fewer TNF-α， thereby promoting the expression of lipolysis-related markers， and TNF-α synergized with lipase to promote lipolysis. It has not been reported that Lacticaseibacillus paracasei modulated lipid metabolism via the lipolysis pathway， which suggested that K56 may regulate glycolipid metabolism of the host by maintaining immune homeostasis.

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A novel lambda negative-resistance transistor in the 0.5 μm standard CMOS process

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Chinese Science Bulletin 2012年第7期57卷 716-718页

作者： Yan Chen LuHong Mao weilian Guo Xin Yu ShiLin Zhang Sheng Xie School of Electronic Information Engineering Tianjin University Tianjin China

A novel negative-resistance transistor (NRT) with a Lambda shaped I-V characteristic is demonstrated in the 0.5 μm standard CMOS process. To save on the number of component devices, this device does not use standard device models provided by CMOS processes, but changes a MOSFET and a BJT into a single device by fabricating them in the same n-well, with a p-type base layer as the MOSFET's substrate. The NRT has a low valley current of -6.82 nA and a very high peak-to-valley current ratio of 3591. The peak current of the device is -24.49 μA which is low enough to reduce the power consumption of the deivce, and the average value of its negative resistance is about 32 kΩ. Unlike most negative-resistance devices which have been fabricated on compound semiconductor substrates in recent years, this novel NRT is based on a silicon substrate, compatible with mainstream CMOS technology. Our NRT dramatically reduces the number of devices, minimizing the area of the chip, has a low power consumption and thus a further reduction in cost.

关键词： CMOS工艺负阻晶体管 lambda 使用标准 MOSFET 设备型号化合物半导体 CMOS技术

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产γ-氨基丁酸乳杆菌高效筛选方法的建立

中国乳品工业 2024年第4期52卷 34-37,49页

作者：范城飞翟征远王然郝彦玲孙婷马霞刘福东赵雯洪维錬中国农业大学食品科学与营养工程学院北京100083 中国农业大学营养与健康系北京100193 内蒙古乳业技术研究院有限责任公司呼和浩特010110 内蒙古伊利实业集团股份有限公司呼和浩特010110

本研究首先发现11株短乳杆菌皆产生大量气体导致培养管盖子弹起,进一步对48 h发酵液pH进行测定,发现有3株菌的发酵液具有较高pH,薄层层析结果表明产生大量气体且发酵液pH较高的菌株能够产生γ-氨基丁酸(GABA),进一步通过质谱实验验证,... 详细信息

本研究首先发现11株短乳杆菌皆产生大量气体导致培养管盖子弹起,进一步对48 h发酵液pH进行测定,发现有3株菌的发酵液具有较高pH,薄层层析结果表明产生大量气体且发酵液pH较高的菌株能够产生γ-氨基丁酸(GABA),进一步通过质谱实验验证,产量分别是124.14、203.00、211.50 mg/L。通过高效测序发现11株短乳杆菌GABA合成基因簇结构和核酸序列基本相同,因此在基因层面无法实现高效筛选。根据GABA生物合成过程中产生二氧化碳及消耗氢离子的现象建立高效筛选方法。进一步对220株植物乳杆菌进行产气观察结合pH测定判定菌株是否产GABA,并通过薄层色谱进行验证,表明此方法可行。该方法具有低成本高效的特点,能够快速从大量乳杆菌中筛选出产GABA菌株。

关键词： γ-氨基丁酸乳杆菌高效

Cancer cells corrupt normal epithelial cells through miR-let-7c-rich small extracellular vesicle-mediated downregulation of p53/PTEN

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International Journal of Oral Science 2022年第4期14卷 470-478页

作者： weilian Liang Yang Chen Hanzhe Liu Hui Zhao Tingting Luo Hokeung Tang Xiaocheng Zhou Erhui Jiang Zhe Shao Ke Liu Zhengjun Shang The State Key Laboratory Breeding Base of Basic Science of Stomatology(Hubei-MOST)&Key Laboratory for Oral Biomedicine Ministry of Education School and Hospital of StomatologyWuhan UniversityWuhanChina Shenzhen PKU-HKUST Medical Center(Peking University Shenzhen Hospital) ShenzhenChina Department of Oral and Maxillofacial Surgery School and Hospital of StomatologyWuhan UniversityWuhanChina Department of Oral and Maxillofacial-head and Neck oncology School&Hospital of StomatologyWuhan UniversityWuhanChina

Tumor volume increases continuously in the advanced stage, and aside from the self-renewal of tumor cells, whether the oncogenic transformation of surrounding normal cells is involved in this process is currently unclear. here, we show that oral squamous cell carcinoma(OSCC)-derived small extracellular vesicles(s EVs) promote the proliferation, migration, invasion, and epithelial-mesenchymal transition(EMT) of normal epithelial cells but delay their apoptosis. In addition, nuclear-cytoplasmic invaginations and multiple nucleoli are observed in s EV-treated normal cells, both of which are typical characteristics of premalignant lesions of OSCC. Mechanistically, mi Rlet-7c in OSCC-derived s EVs is transferred to normal epithelial cells, leading to the transcriptional inhibition of p53 and inactivation of the p53/PTEN pathway. In summary, we demonstrate that OSCC-derived s EVs promote the precancerous transformation of normal epithelial cells, in which the mi R-let-7c/p53/PTEN pathway plays an important role. Our findings reveal that cancer cells can corrupt normal epithelial cells through s EVs, which provides new insight into the progression of OSCC.

关键词： cor invasion transferred

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泻火解毒法治疗原矛头蝮蛇咬伤的临床观察

蛇志 2024年第3期36卷 277-280,284页

作者：陈福伟王世军张美吉赵玉楣杨尾莲沈芳华福建中医药大学附属人民医院蛇伤科福建福州350004

目的观察泻火解毒法治疗原矛头蝮蛇咬伤的临床疗效。方法选择2022年7月1日至2023年8月1日在我院治疗的原矛头蝮蛇咬伤患者108例,按随机数字表法分为治疗组和对照组各54例。对照组给予常规治疗,治疗组在对照组的基础上给予口服蛇伤胶囊(... 详细信息

目的观察泻火解毒法治疗原矛头蝮蛇咬伤的临床疗效。方法选择2022年7月1日至2023年8月1日在我院治疗的原矛头蝮蛇咬伤患者108例,按随机数字表法分为治疗组和对照组各54例。对照组给予常规治疗,治疗组在对照组的基础上给予口服蛇伤胶囊(泻火解毒法治疗毒蛇咬伤代表方)治疗,观察两组患者治疗后第1、3、5、7天时的患肢周径差、肿胀消退时间、治疗疗程及患肢疼痛评分。结果两组患者治疗后第1、3天时的患肢周径差比较,差异均无统计学意义(均P>0.05);治疗后第5、7天时,治疗组的患肢周径差明显低于对照组,差异均有统计学意义(均P<0.05)。治疗组的患肢肿胀消退时间、治疗疗程均短于对照组,差异有统计学意义(均P<0.05)。治疗第3、5、7天时,治疗组的患肢疼痛评分均明显低于对照组,差异均有统计学意义(均P<0.05)。结论泻火解毒法治疗原矛头蝮蛇咬伤的临床疗效好,值得推广应用。

关键词：蛇伤胶囊原矛头蝮蛇咬伤泻火解毒法肢体肿胀临床疗效疼痛评分

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无铅喷锡堵孔不良探讨与改善

印制电路资讯 2024年第4期 76-81页

作者：黄伟黄李海许伟廉罗登峰杨梓新李长生洪延博敏电子股份有限公司省市共建高密度混合集成印制电路广东省重点实验室广东梅州514000

随着新能源的快速发展,对能源用印制电路板的需求也越来越多,而能源印制板在设计上多为内层芯板铜厚大于等于2OZ和无铅喷锡,且PTH孔多数需进行喷锡,客户端不接受锡堵孔现象;这就对喷锡的品质要求较为严苛;改善喷锡堵孔就显得尤为重要,... 详细信息

随着新能源的快速发展,对能源用印制电路板的需求也越来越多,而能源印制板在设计上多为内层芯板铜厚大于等于2OZ和无铅喷锡,且PTH孔多数需进行喷锡,客户端不接受锡堵孔现象;这就对喷锡的品质要求较为严苛;改善喷锡堵孔就显得尤为重要,本文主要通过实验验证,在现有参数范围内,通过对风刀温度、风刀压力以及风刀间距的参数进行优化,达到改善的目的,为后续生产提供技术依据。

关键词：能源印制板喷锡堵孔风刀温度风刀压力风刀间距

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“嫦娥一号”卫星的调相轨道设计

中国空间科学技术 2010年第1期30卷 18-24页

作者：杨维廉中国空间技术研究院北京100094

中国第一颗月球探测卫星"嫦娥一号"的飞行轨道的设计中采用了调相轨道,在"长征三号甲"运载火箭提供的超地球同步转移轨道与地月转移轨道之间增加了一段由周期为24h和48h轨道构成的环绕地球飞行的调相轨道。为了将几条不同的轨道精确地... 详细信息

中国第一颗月球探测卫星"嫦娥一号"的飞行轨道的设计中采用了调相轨道,在"长征三号甲"运载火箭提供的超地球同步转移轨道与地月转移轨道之间增加了一段由周期为24h和48h轨道构成的环绕地球飞行的调相轨道。为了将几条不同的轨道精确地拼接起来,必须考虑地球引力场对轨道的摄动影响。克服这个难点的做法是基于经典的轨道摄动理论,先将整段调相轨道设计为考虑地球引力场J2项影响的平轨道,在与运载的发射轨道拼接时,先将运载的包括短周期摄动的瞬时轨道转换为平轨道,在与地月转移轨道拼接时将调相轨道转换成拼接点的瞬时轨道。由于采用了平轨道的处理方法使得轨道控制策略的表述十分简明并易于操作。

关键词：月球探测地月转移轨道调相轨道轨道摄动卫星

Tunnel vision optimization method for VR flood scenes based on Gaussian blur

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International Journal of Digital Earth 2021年第7期14卷 821-835页

作者： Lin Fu Jun Zhu weilian Li Qing Zhu Bingli Xu Yakun Xie Yunhao Zhang Ya Hu Jingtao Lu Pei Dang Jigang You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Department of Information and Communication The Army Academy of Armored ForcesBejingPeople’s Republic of China

The visualization of flood disasters in virtual reality(VR)scenes is useful for the representation and sharing of disaster knowledge and can effectively improve users’cognitive efficiency in comprehending disaster ***,the existing VR methods of visualizing flood disaster scenes have some shortcomings,such as low rendering efficiency and poor user *** this paper,a tunnel vision optimization method for VR flood scenes based on Gaussian blur is *** key techniques are studied,such as region of interest(ROI)calculation and tunnel vision optimization considering the characteristics of the human visual system.A prototype system has been developed and used to carry out an experimental case *** experimental results show that the number of triangles drawn in a flood VR scene is reduced by approximately 30%–40%using this method and that the average frame rate is stable at approximately 90 frames per second(fps),significantly improving the efficiency of scene rendering and reducing motion sickness.

关键词： Flood disaster virtual reality Gaussian blur tunnel vision scene optimization