Kármán vortex street in a spin–orbit-coupled Bose–Einstein condensate with PT symmetry

The dynamics of spin–orbit-coupled Bose–Einstein condensate with parity-time symmetry through a moving obstacle potential is simulated numerically. In the miscible two-component condensate, the formation of the Kármán vortex street is observed in one component, while ‘the half-quantum vortex street' is observed in the other component. Other patterns of vortex shedding, such as oblique vortex dipoles, V-shaped vortex pairs, irregular turbulence, and combined modes of various wakes, can also be found. The ratio of inter-vortex spacing in one row to the distance between vortex rows is approximately0.18, which is less than the stability condition 0.28 of classical fluid. The drag force acting on the obstacle potential is simulated. The parametric regions of Kármán vortex street and other vortex patterns are calculated. The range of Kármán vortex street is surrounded by the region of combined modes. In addition, spin–orbit coupling disrupts the symmetry of the system and the gain-loss affects the local particle distribution of the system, which leads to the local symmetry breaking of the system, and finally influences the stability of the Kármán vortex street. Finally, we propose an experimental protocol to realize the Kármán vortex street in a system.

Factors Contributing to Contamination of Street Foods in Bamako, Mali

The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako.

Assessment of Physico-Chemical and Microbial Quality of Sugarcane Juice Sold by Street Vendors in Three Regions of Bangladesh

Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, PH, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, PH, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 105 - 43.6 × 105 cfu/ml, 4.6 × 105 - 21.6 × 105 cfu/ml and 3.6 × 105 - 36.6 × 105 cfu/ml respectively, where the permitted value is 1.0 × 104 cfu/ml, whereas the total coliform count was ranged from 0.4 × 105 - 6.4 × 105 cfu/ml, 0.6 × 105 - 8.4 × 105 cfu/ml and 0.00 - 8.4 × 105 cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 105 - 56.5 × 105 cfu/ml, 21.5 × 105 - 54.5 × 105 cfu/ml and 32.5 × 105 - 68.5 × 105 cfu/ml, where the permitted value is 1000 cfu/ml. According to the Gulf standard, the microbiological parameters of all the collected sugar cane juice were out of the permitted standards, so that a serious health outbreak can be caused anytime.

Design Strategy of Street Space Micro Renewal: A Case Study of Baihuazhou District of Nanchang City

Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street is a linear element of urban public space, and it is of great significance forimproving the quality of urban public space by studying the micro renewal design strategy of street space.Based on the interpretation of two urban renewal cases, Wangjing Street in Beijing and Mengzhuiwan inChengdu, taking Baihuazhou area in Nanchang City as an example, this paper analyzes the main problemsin the current situation of street space in Baihuazhou area from three aspects: space use, traffic organization,and waterfront space creation, and explores the micro renewal design strategy of the street space.

Spatial Distribution Characteristics and Coverage Rate of Commercial Facilities in 15-minute Radius Livelihood Service Circles of Chunshu Street

Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved.

Commuting Space of Primary and Secondary Schools in the Context of Child Friendly Cities:A Case Study of Bajiao Street of Shijingshan District

With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city.

Time Street

On a cold morning,I inadvertently opened a door-the door of oblivion…In a flash,I found myself on a street.Two big words appeared before my eyes:“Time Street”.But there were few people on the street,and it was not as I had imagined.

Application of Smart Streetlights in Urban Road Lighting

The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent years,with the technological and economic development,smart street lighting has gradually emerged.Key functions of smart street lighting include road illumination,cultural promotion,meteorological monitoring,public broadcasting,and 5G micro-base stations.The overall quality of smart street lighting construction directly impacts the effectiveness of urban development and the city’s comprehensive growth.This paper analyzes the concept of smart street lighting,its advantages and disadvantages,the functionalities of smart street light systems,and the application of smart street lighting in urban road illumination.

The Impact of Street Interviews on Chinese EFL Undergraduates’Intercultural Communicative Competence

The study adopts Byram’s Intercultural Communicative Competence(ICC)model as the theoretical framework,and structured interviews were conducted to explore the impact of street interviews on the participants’ICC.Analysis results revealed street interviews help students acquire knowledge in intercultural attitudes,intercultural knowledge,skills of discovery and interaction,and critical cultural awareness,aligning with the four components of Byram’s ICC model.Meanwhile,they have positive perceptions of street interviews.Therefore,street interviews have a positive effect on the development of participants’ICC.

High Prevalence of Musculoskeletal Disorders and Self-Medication among Street Vendors in Bangui, Central African Republic (CAR)

Introduction: Musculoskeletal disorders (MSDs) are a set of peri-articular conditions that result mainly in pain and functional discomfort. They represent a major occupational health problem in all areas of activity. The objective of this work was to determine the prevalence of MSDs among street vendors in the city of Bangui in the Central African Republic (CAR). Methods: A cross-sectional study was conducted from September 01 to October 31, 2021 in Bangui, the capital of CAR. The study population consisted of street vendors which were included at the entrance of 4 large markets of Bangui after giving informed consent. The sample size, calculated according to the Schwartz formula, was 384. Sociodemographic data (age, gender, level of education, marital status), professional data (the duration of sale in hours, the distance traveled per day);and health data (the health problems suffered by itinerant sellers and the means of dealing with them) were collected using a pre-established self-questionnaire. This collected data was processed using Microsoft Excel 2013 and Epi-Info version 7 software. Results: Among 384 street vendors included, women represented a quarter (24.9%). The average age was 27 years;the 25-34 age group was the most represented (50%). About two-thirds (64.8%) sold for at least 12 hours and traveled more than 10 km (69.3%) per day. The main health problems reported by street vendors were musculoskeletal disorders (95.8%). Their locations concerned the upper limbs shoulder 65.36% (251), elbow 24.22% (93). Non-ergonomic postures that stress the back and joints all day long, causing pain are risk factors for MSDs. These MSDs were treated by self-medication with non-steroidal anti-inflammatory drugs (22.0%), mainly sold on the street. Conclusion: MSDs dominated the health problems of street vendors. These problems raise the need for recognition and support for these workers to optimize their performance while preserving their health through awareness and good management of MSDs whose chronicity generates a disability.

Changes of Street Quality Based on Street View Images in Different Periods:A Case Study of Jingshan East Street,Dongcheng District,Beijing City

With the continuous calls for energy conservation and emission reduction in recent years,more and more people choose walking as their travel mode.The improvement of the quality of street space will directly affect people's willingness to walk.By sorting out relevant research on street quality measurement,extracting quality keywords with high frequency of reference as impact factors,and using street view image data from different eras,semantic segmentation technology,factor analysis,and questionnaire survey methods,this paper evaluates the street quality of Jingshan East Street,Dongcheng District,Beijing,further explores the impact of different factors on street quality,and analyzes possible ways to improve it.

Impact of Street Built Environment on Human Thermal Comfort in Summer

With the continuous intensification of the global greenhouse effect,thermal comfort has become a highly concerned issue in the living environment.The study explores the influencing factors and improvement strategies of urban street thermal comfort.The urban heat island effect,environmental parameters,building layout,and green planting all have a significant impact on the thermal comfort of streets.Improvement strategies include optimizing cultivating pattern of plants,adjusting street layout,and improving paving materials of road.The multi-layer vegetation structure provides green shade,reduces local temperature,and humidifies the surrounding environment.It should adjust the street orientation and aspect ratio to provide sunlight and ventilation,and reduce ambient temperature.Paving materials with low reflectivity and light color and permeable underlying surface should be chosen to reduce heat absorption,increase shading and greenery,and improve thermal comfort.

Influence of Urban Street Greening Design under the Concept of Green Healthy Cities:A Case Study of Hefei City

In order to explore the influence of urban street greening,the street landscape of Changjiang West Road and Xiyou Road in Hefei City was selected as the research sample to study the design of urban street landscape under the concept of green healthy cities.The results show that the urban street landscape of Hefei City is single in design and plant type,and plant maintenance management is not good.It is proposed to strengthen the maintenance and management of street greening,increase the types of native plants,and improve cultural connotation,so as to enhance the artistry,regionalism and functionality of urban street landscape in Hefei City.

Travel Patterns and Street Networks: A Novel Visualization Methodology of City-Level Traffic Flows and Network Usability

Street Networks, knitted in the urban fabric, facilitate spatial movement and control the flow of urbanization. The interrelation between a city’s spatial network and how the residents travel over it has always been of high interest to scholars. Over the years, multifaceted visualization methods have emerged to better express this travel trend from small to large scale. This study proposes a novel approach to 1) visualize city-wide travel patterns with respect to the street network orientation and 2) analyze the discrepancies between travel patterns and streets to evaluate network usability. The visualizations adopt histograms and rose diagrams to provide several insights into network-wide traffic flows. The visualization of four New York City (NYC) boroughs including Queens, Brooklyn, Bronx, and Staten Island was generated for the daily traffic and the average hourly flows in the morning and evening rush hours. Then the contrasts between built-in street network topology and travel orientation were drawn to show where people travel over the network, travel demand, and finally which segments experience high or light traffic, revealing the true picture of network usability. The findings of the study provide an insight into the novel and innovative approach that can help better understand the travel behavior lucidly and assist policymakers in decision making to maintain a balance between urban topology and travel demands. In addition, the study demonstrates how to further investigate city street networks and urbanization from different diverse dimensions.

Inclusiveness in City Centre-A Case Study: 30-E-Tir Street in Tehran

City centres in today’s big cities,particularly in metropolises and megalopolises,play a crucial role in revival of human scale in an urban context.Nowadays,a city centre that corresponds to needs of various groups of users,contributes to creating a safe,healthy,vibrant,inclusive and sustainable city.Accordingly,identification of the major and minor groups of users of city centres as well as their likes,dislikes and preferences is a primary step.To this end,this paper investigates the city centre of Tehran and a recently pedestrianised street called 30-E-Tir.With a focus on the three indicators of age,gender and speed,this paper aims to elucidate the existing divergent groups of users of 30-E-Tir and their physical,mental,and spiritual expectations of this street.This 1.3-km street-as a linear path incorporating food&junk food kiosks and the associated small-scale canopies,and flagstone floorscaping-passes through many famous museums of Tehran.These specific features have converted 30-E-Tir Street into a convivial destination point for Tehranians.The existing problems,however,necessitate a detailed investigation of the current situation.The applied methodology for this qualitative-quantitative analysis of the present condition includes the literature review and the related analysis,direct appraisal,photography,and dot-based analysis.

The Tragedy on Females in V.S.Naipaul’s Miguel Street

The tragic features of V.S.Naipaul’s short story collection Miguel Street are more typical in the female characters.This paper attempts to analyze the typical female tragic characters in the book.Starting from their stories and experiences,it deeply explores the survival pressure and challenges faced by females on the post-colonial land under the influence of colonial rule.Through in-depth analysis of typical female tragedies,the author tries to provide more possibilities for the survival of post-colonial females,and further illustrates that the tragedy of post-colonial females is caused by marginal males and imperial colonial hegemony in Miguel Street.

Study of Spatial Characteristics of Streets and Alleys in Traditional Villages:Taking Pingtan Comprehensive Experimental Area as an Example

Taking the traditional residential street space in Pingtan Comprehensive Experimental Area as an example,the factors influencing the formation and development of lane space and the distribution characteristics of lanes were analyzed in this paper.Subsequently,an analysis was conducted on the scale and proportion of street and lane space enclosed in the settlement,the experiential aspects of street and lane space,as well as the node space.Lastly,a systematic summary of the street space characteristics in the settlements of Pingtan Island and Dongxiang Island is presented.

Navigating Temporal and Spatial Dimensions:Unveiling the Fictional Essence and Authenticity in the Narrative of The Rise and Fall of Wing Shing Street

The novel The Rise and Fall of Wing Shing Street delves into the reality of Hong Kong residents deeply attuned to spatial awareness but detached from temporal significance,entangling emotions surrounding time and space.Through narrative interruption and extension,the author portrays the genuine struggles of Hong Kong inhabitants-juxtaposing the blurred boundaries of time and space and the inherent rootlessness of reality within a fictionalized framework.Emphasizing the 20th-century human condition,wherein spatial awareness overshadows temporal understanding,the novel underscores the consequences:a loss of history and cultural identity.With a fresh perspective,the narrative explores the interplay of time and space,accentuating both the fictitious and authentic dimensions.This prompts readers to reconsider their history,culture,and the current moment,ultimately highlighting the pivotal role of temporal awareness.

文化基因视角下历史街巷沿街建筑保护更新策略研究——以聊城米市街为例

以聊城米市街为例,沿街建筑包含大量可更新的传统风貌建筑、部分需整治的普通建筑及少量需原样修缮的历史建筑,在建筑更新中出现严重的传统风貌破坏问题。基于此,研究借助文化基因理论,从原始基因模式、派生基因模式与延续基因模式3个层级探讨各类建筑保护修缮、保护更新与整治的设计策略,进而指导历史街巷沿街建筑风貌有序更新。

从街道场所到城市区域:美国城市宜居性的研究与实践

“宜居性”是20世纪60年代以来美国人本主义城市设计中的重要议题。区别于现代主义带有浓重乌托邦色彩的宏大城市构想,宜居性理论重点关注微小叙事和日常生活。文章通过详细梳理20世纪60年代以来美国宜居性理论研究和实践的发展历程发现:1996年以前的宜居性研究聚焦于街道—场所尺度,包含两条研究脉络,即从安全的街道到复合型林荫大道和从交往的场所到公共领域的重塑;1996年以后,新城市主义理论的发展推动了“街道—社区—城市—区域”多尺度融合的宜居性研究和实践。在此基础上,对我国的宜居城市建设提出3点启示:以人为本,优化步行和公交系统;关注日常生活,鼓励公共参与;注重多尺度空间要素的一致性和完整性。