Search

"Breaks in the Air: The Birth of Rap Radio in New York City" by John Klaess is a significant contribution to the history of New York hip-hop culture. The book explores the early days of rap radio in New York, when stations like WBLS played a crucial role in shaping the sound and culture of hip-hop. Klaess uses interviews and cassette recordings to provide insights into the inseparable relationship between rap, radio, and diverse listening communities. The book also examines the impact of deregulation on the commercial radio industry and the role of radio in advancing Black social progress. Overall, "Breaks in the Air" offers a valuable perspective on the history of rap radio in New York City. [Extracted from the article]

A high-precision mechanized seeding can greatly contribute to the vegetable production at present. In this study, a spotting glue-paper tape precision seeder was designed for the small seed vegetables, particularly combining the seed rope and printing seeding. Three components were also divided in the seeder, including the peristaltic pump glue, ratchet spotting glue, and seed metering device. Among them, the glue was a mixture of pregelatinized starch and water. Specifically, the glue volume and viscosity were the main factors affecting the number of adhered seeds. The glue point volume depended mainly on the rotation angle of the peristaltic pump during the movement. A pretest of seed adhesion was carried out to preliminarily determine the mass ratio of pregelatinized starch to water (less than 1:5), representing the glue viscosity. Furthermore, the frequency of pump and dispensing were analyzed to clarify the relationship between the peristaltic pump and ratchet speed, where the number of ratchet teeth was determined to be 4. As such, the matching was realized between the peristaltic pump and ratchet spotting glue. The ratchet profile was also designed, according to the spotting glue motion. A theoretical analysis was made on the movement of seeds in the seed guiding tube. It was found that the aggregation effect of seeds on the paper tape relied on the length and cross-sectional angle of the seed guiding tube, as well as the rotation speed of the socket wheel. The seed guiding tube was then optimized for the optimal structural parameters. A Box_Behnken test was also carried out, where the length and cross-sectional angle of the seed guiding tube, while the rotation speed of the socket wheel was taken as the test factors, whereas, the percentage of seeds in the effective area on the paper tape was taken as the test index. The results showed that the percentage of seeds in the effective area on the paper tape was 57.23%, when the length of the seed guiding tube was 56 mm, the section angle was 35°, and the rotation speed of the seed metering wheel was 30 r/min. An adhesion test was also performed on the Shanghai Qing 605 seeds with a diameter of 1.5-2.0 mm. The test factors were then selected as the roller angle of the peristaltic pump and the mass ratio of pregelatinized starch to water. An optimal combination of parameters was achieved, including the size of the glue point, and the mass ratio of pregelatinized starch to water. Once the roller rotation angle was 10° and the mass ratio of pre-gelatinized starch to water was 1:6, the single seed rate of glue point adhesion to seeds reached 97.4%. The adaptability test was also carried out on the whole machine on the working performance of different varieties of small seed vegetables. It was found that the single seed rates of Shanghai Qing 605 and Siji Chinese cabbage seeds were greater than 95% under the working speed of 0.5-1.5 m/s, whereas, the coefficient of variation of plant spacing was less than 10%, fully meeting the requirements of precision sowing indicators that specified in the standard NY/T1143-2006. Therefore, the single seed rate and the working efficiency of the improved seeder increased by 3.53%, and 50% than before. [ABSTRACT FROM AUTHOR]

Adam Lowenstein's book, "Horror Film and Otherness," explores the social relevance and transformative power of horror cinema. Lowenstein argues that horror films can teach us about otherness and illuminate the ongoing evolution of social norms and identities. He challenges Robin Wood's analysis of American horror cinema, offering a more nuanced understanding of the genre's exploration of trauma, alienation, and displacement. Lowenstein engages with theorists and historians to examine the themes of aging, the body, gender, and sexuality in horror films from the 1970s to the present. While the book is comprehensive, it lacks coverage of trans people, which would further contribute to the exploration of otherness. Overall, "Horror Film and Otherness" is a landmark text that highlights the importance of horror in understanding society and the self. [Extracted from the article]

Approaching the writing of a scene in this way, the authors argue, makes character motivations clear, creates tension and leaves room for either additional obstacles or resolution. Which points to another fundamental premise that Perry and Sanders believe in, namely that every scene needs to have both a goal and an obstacle. I SceneWriting: The Missing Manual for Screenwriters i by Chris Perry and Eric Henry Sanders is an essential primer on the important foundational structure and elements that make a scene - and by extrapolation, a story - work. [Extracted from the article]

"Black Women and the Changing Television Landscape" by Lisa M. Anderson is a book that examines the portrayal of Black women on television throughout history. Anderson, an associate professor of women and gender studies, builds on her previous work to explore the complex and evolving representations of Black women in media. Using a semiotic approach and drawing on the work of Black feminist scholars, Anderson analyzes specific television shows and personalities from the 1950s to the present. The book goes beyond simplistic judgments and aims to understand the historical and cultural contexts in which these representations exist, as well as the agency of Black women in shaping them. It is a valuable resource for scholars in cultural, media, and television studies. [Extracted from the article]

Recent advances in non-volatile main memory (NVM) technology have spurred research on algorithms that are resilient to intermittent failures that cause processes to crash and subsequently restart. In this paper we present a Recoverable Mutual Exclusion (RME) algorithm that supports abortability. Our algorithm guarantees FCFS and a strong liveness property: processes do not starve even in runs consisting of infinitely many crashes, provided that a process crashes at most a finite number of times in each of its attempts. On DSM and Relaxed-CC multiprocessors, a process incurs O (min (k , log n)) RMRs in a passage and O (f + min (k , log n)) RMRs in an attempt, where n is the number of processes that the algorithm is designed for, k is the point contention of the passage or the attempt, and f is the number of times that p crashes during the attempt. On a Strict CC multiprocessor, the passage and attempt complexities are O(n) and O (f + n) , respectively. Our algorithm uses only the read, write, and CAS operations, which are commonly supported by multiprocessors. Attiya, Hendler, and Woelfel proved that, with any mutual exclusion algorithm, a process incurs at least Ω (log n) RMRs in a passage, if the algorithm uses only the read, write, and CAS operations (in: Proc. of the Fortieth ACM Symposium on Theory of Computing, New York, NY, USA, 2008). This lower bound implies that the worst-case RMR complexity of our algorithm is optimal for the DSM and Relaxed CC multiprocessors. This paper is an expanded version of our conference paper as reported by Jayanti and Joshi (in: Atig and Schwarzmann (eds) Networked Systems. Springer International Publishing, Cham, 2019), which presented the first Recoverable Mutual Exclusion (RME) algorithm that supports abortability. This algorithm from our conference paper (in: Atig and Schwarzmann (eds) Networked Systems. Springer International Publishing, Cham, 2019) admits starvation when there are infinitely many aborts in a run. In this paper, we fix this shortcoming and prove the algorithm's properties by identifying an inductive invariant. [ABSTRACT FROM AUTHOR]

Ceremony Men: Making Ethnography and the Return of the Strehlow Collection: By Jason M. Gibson. The collection in question in Gibson's study is that assembled by linguist and ethnographer T.G.H. ("Ted") Strehlow, now housed at the purpose-built Strehlow Research Centre in Alice Springs. This brings me to the second innovation that Gibson makes in approaching Strehlow's archive: his decision to focus on the work that Strehlow did with the Anmatyerr. [Extracted from the article]

This paper develops the notion of "platform placemaking", describing how platforms mobilize user data to remake urban spatial imaginaries in their interests. Using Airbnb as a case, the paper studies the digital urban culture of "Airbnbification" – examining how Airbnb's reviews and descriptions become part of reshaping urban place, while contributing to the place alienation of long-term residents. Airbnb feeds a surge in urban tourists on the hunt for "real urban experiences": off-the-beaten-track, everyday and mundane urban life, seen as representing something "real" and "authentic". This paper situates Airbnb in the literature on postmodern consumption, and examines the way hosts and guests on Airbnb stage, perform and construct cosmopolitanism and "authentic" urban place to cater to the values of new urban tourism. The paper introduces an approach to studying digital urban culture through platform data, using computational discourse analysis to examine Airbnb in New York City. By linking narratives in reviews and neighborhood descriptions to census data, we examine how authenticity and cosmopolitanism is staged and marketed. The paper argues that Airbnb serves to promote a value system that devalues the cultural and spatial capital of long-term residents, implying that the new tourists' cosmopolitan longing to belong may thus come at the cost of the locals' own sense of belonging. The platform placemaking of Airbnb thus emphasizes urban place as a consumption experience, while depressing other ways of experiencing the city. [ABSTRACT FROM AUTHOR]

Protests during the 2021 Climate Conference in Glasgow exemplified our dilemma. The establishment perpetuates old thinking, while young people demand a new approach to mitigate the impact of climate change. The authors agree with the young people, and as a solution we propose to replace the current fragmentary approach with a new holistic one. The passive house approach that was conceptualized by the University of Illinois and built in Canada in 1977 showed us that energy consumption can be reduced about half of that used in the traditional design. Seventeen years later, a European passive house was built in Darmstadt. In 2008, a demonstration house in Syracuse, NY, showed that integrated passive measures produced energy use by about half of the NY state code for 2004. At the same time, some advanced houses in the USA showed total energy use of about 70 kWh/(m2∙y). In 2008, at the first Building Enclosure Science and Technology Conference, two equally important objectives for 2030 were proposed by the Lawrence Berkeley National Laboratory: (1) a 90% reduction of energy use in new buildings and (2) 50% for the retrofitting of existing buildings, i.e., to the level achieved in the 1980s. The first objective has recently been achieved in small buildings while the large residential buildings remain on the level obtained in the 2000s. Yet, the retrofitting of existing buildings (the second objective) has been a dismal failure. This paper acknowledges progress in hydronic heating and cooling involving electric heat pumps and hybrid solar panels, building automatics used for operation of HVAC, and modification of air distribution systems that comes from experience with the SARS-CoV-2 pandemic. Furthermore, it highlights that to accelerate energy efficiency and carbon emission reductions, there must be broad public-private educational programs with demonstrations of a new generation of retrofitting. Economically and ecologically retrofitted buildings will create a new approach to real estate investment. [ABSTRACT FROM AUTHOR]

Fashioning James Bond: Costume, Gender and Identity in the World of 007: LLEWELLA CHAPMAN, 2022 London, NY, Bloomsbury Academic pp. xii + 320, illus., £65.00 (cloth), £19.99 (paper) Bond, James Bond, is synonymous with many iconographic elements, from gadgets and guns to megalomaniac foes with dastardly schemes, but the sharp-suited hero and the bikini-clad Bond girl are undoubtedly some of the franchise's most recognizable icons and absolutely central to its ongoing appeal. But despite being organized by Bond, the focus does not rest exclusively on the hero himself and there is plenty of space dedicated to discussing the costuming of those aforementioned Bond girls, later re-labelled Bond women, his bosses and colleagues, as well as the villains and their inevitable henchmen. [Extracted from the article]

The article reviews the exhibition "Uche Okeke: Works on Paper, 1958-1993" at the Skoto Gallery in New York City on January 15-February 21, 2015.

Throughout the 1970s, a drive towards the diversification of mediums available to artists led to artists working across numerous mediums not usually associated with visual art. While some came to work with sound as a central focus in their practice, most used sound as a medium to be employed in particular artworks for conceptual purposes. The paper is focused on five audio and sound exhibitions presented in New York City between 1978 and 1984. These large group exhibitions were held in alternative art spaces and not-for-profit art galleries and have received little critical attention beyond reviews published in local newspapers and art magazines. As such, these exhibitions have all but disappeared from the history of sound in art and from art history in general. I will argue that this cluster of group shows signal to an emergent practice that was moving past the post-medium condition and conceptual art towards the postmodernism of the 1980s. These exhibitions point to an understanding of sound as a medium of visual art that is at odds with contemporary scholarship in the sonic arts, which favours a music-based understanding of approaches to sound within the art gallery. [ABSTRACT FROM AUTHOR]

Drawing on the archives of the electrical spectacular designer Douglas Leigh, this essay demonstrates the benefits of approaching the papers of commercial artists and advertisers from an art-historical perspective. Leigh's substantial archive documenting decades of production in New York City would arguably be better placed in a collection like the National Museum of American History, which has strengths in the history of advertising. But what might this change of context render invisible in a collection like the Douglas Leigh Papers? [ABSTRACT FROM AUTHOR]

The grid plays a prominent role in architecture, aiding in space organization and influencing all aspects of planning, ranging from urban design to intricate building details. This paper posits that the grid receives heightened emphasis in Brutalism, particularly in constructivist Brutalism, where materials and construction are intentionally exposed. A question arises regarding the grid's characteristics—despite its subtle appearance, the grid can sometimes be deceptive, ambiguous, and manipulative. The paper analyzes the merits and drawbacks of employing the grid in architecture, shedding light on its contributions to both structural and perceptual comprehensibility, as well as its role in increasing usefulness. To illustrate the application and perception of the grid, the paper examines two primary planning levels: urban planning and building design. The case studies focus on examples from New York City housing developments, specifically those constructed between the 1950s and the 1970s, and projects by architect I. M. Pei, which offer valuable insights into practical implementation. The paper concludes that while the grid can establish order, it may also engender an "uncanny" feeling. [ABSTRACT FROM AUTHOR]

The article discusses the papers and photographs of composer and conceptual photographer Cosmos Andrew Sarchiapone which dealt with the intersecting worlds of theater, music, art and film in 1970s New York City. Topics include the contents of the Cosmos Papers which includes artworks and scores for plays, and the documentations of key personalities of the 1970s New York underground.

Presents abstracts of papers presented at the Association of American Geographers' 1942 meeting in New York City. "Rural-Urban Population Ratios," by Alford Archer; "Land Classification in the Matanuska Valley," by Meredith F. Burrill; "Siberian Resources for Soviet Warfare," by George B. Cressey; "Geographical distribution of human productivity," by Ellsworth Huntington. [ABSTRACT FROM AUTHOR]

Current bridge assets management (BAM) is based on a site inspection–based condition rating methodology. Mitigation measures are adapted to assets' condition assessment results. The reaction approach of bridge infrastructure structural evaluation does not help in judicious planning for repair and rehabilitation in prioritization for bridge assets management. This research paper presents a risk assessment method (RAM) developed upon the statistical data analysis using analytical tools and techniques of the aging effect on the corrosion anomaly rate (CAR), as proposed by the authors. The proposed RAM methodology is developed in order to provide the bridge asset manager with an analytical tool for risk-based BAM optimization. A cluster of 92 New York City Department of Transportation (NYCDOT) steel girder with reinforced concrete deck bridges was selected. The main objectives of this research paper are to (1) develop a risk rating methodology (RAM) for preemptive bridge assets management, (2) compare the RAM-based risk rating (RR) with the primary member condition rating (CR) of 92 NYCDOT nonrehabilitated steel girder with reinforced concrete deck bridges, and (3) provide analytical tools for bridge life-cycle determination for different vulnerability levels and for forecasting the financial risk of prolonged delayed rehabilitation. This innovative paper illustrates the RAM application for predicting the aging process on the CAR and its disposition for a preemptive BAM planning and development. Practical Applications: Extending the useful service life of aging bridges is a critical issue of global interest. One problem faced globally by the transportation industry is the degradation of structural components of bridges. The purpose and practical application of this paper is to demonstrate a risk assessment approach for BAM relying on statistical data analysis for prioritizing the repair/rehabilitation of deteriorating bridge system. This research presents the deterioration rate concept in BAM framework consisting of estimating the useful service life expectancy of deteriorating bridge system through statistical data analysis, developing a deterioration rate model. The current BAM is based on a site inspection–based condition rating methodology, which depends upon structural evaluator's judgments. The outcomes of this research have demonstrated, through statistical data analysis, that the pattern of aging effects on the time-dependent CAR value may effectively serve as a substantial time-dependent early degradation indicator for life-cycle state evaluation and serviceability performance degradation. BAM provides valuable aid for bridge owner decision makers in forecasting the degradation rate of bridge system and making preemptive decisions for rehabilitation investment prioritization. One practical application of this research is forecasting the cost implications of deferred repair/rehabilitation along with associated financial risk. [ABSTRACT FROM AUTHOR]

Introduction: Symbol and digit substitution tasks are key instruments in the evaluation of attention, speed of processing, executive functioning, and cognitive dysfunction. The Match is an electronic (app-based) substitution task developed as part of the University of California San Francisco Brain Health Assessment that has been used to demonstrate cognitive impairment. We describe the paper-based oral symbol/number substitution task (Paper-Match), which was developed as part of the 5-Cog battery to assess for cognitive impairment including dementia and demonstrate it's use in an urban, multi-ethnic, socioeconomically disadvantaged primary care population in Bronx NY. Method: 109 participants, mean age 72.61 SD 6.42 and education 11.70 SD 3.82 years, 81% female, 48.6% Hispanic/Latino and 47.7% African American seen as part of 5-Cog. Participants (36.7% tested in Spanish) completed the Paper-Match (scored based on the number of correct matches in 90 seconds) and a comprehensive neuropsychological battery. Descriptive and correlational analysis were conducted. Results: Mean Paper-Match score was 38.24 SD 11.83 items correct (range 4–51). Paper-Match performance was highly correlated with performance on the Symbol Digit Modalities Test (r = .819, p < .001) and moderately correlated with performance on the Montreal Cognitive Assessment (MOCA; r = .604, p < .001). Years of education and primary language impacted performances. Conclusion: The results of this study provide the initial description and validation of the Paper-Match an oral symbol digit substitution task and its use in a diverse population of older primary care patients. Further research on the psychometric properties and construct validity of the Paper-Match are needed. [ABSTRACT FROM AUTHOR]

Presents information on a study which screened hemoglobin with alkaline electrophoresis on cellulose acetate followed by acid electrophoresis on citrate agar in New York City. Critical application of specimens to the citrate agar plates of the screening procedure; Accurate monitoring of the hemoglobin screening method; Results and discussion.

Harvesting usable and meaningful disaster-related, spatio-temporal data at a highly granular level poses major challenges in its cleaning and aggregation. This paper presents a strategy related to those challenges with respect to individual behavior near COVID-19 laden healthcare facilities. This is done to enable the visualizing of egress behavior data as interactive, three-dimensional (3D) scenes to investigate human behavior patterns regarding touch-based, disease transmission. Therefore, the aim is to demonstrate how this concept of 3D epidemiology may provide new mechanisms to understand the relative risk and exposure prevalence for data analysis. This paper demonstrates 3D enablement of disaster-related field data through use of first-hand observations of 1,936 individuals egressing New York City healthcare facilities during the onset of COVID-19 in the Spring of 2020. The observations capture egress behavior in terms of where people go (e.g. coffee shop, Subway) and how they physically interact with the surroundings (i.e. what they touch and how long they remain). This paper introduces a mechanism for automated extraction and 3D visualization of such data in Potree, an open-source Web Graphics Library (WebGL) point cloud viewer. Distinctive vertex shaders are used to distinguish specific destination selection and behavioral patterns (e.g. personal protective equipment usage). Two-dimensional heatmaps are paired with 3D scenes to demonstrate the potential of using 3D visualization of spatio-temporal patterns for visualizing disease transmission potential. [ABSTRACT FROM AUTHOR]

In the dynamic realm of big data processing, conquering the challenges imposed by highdimensional datasets is imperative. This paper introduces a groundbreaking advancement in dimensionality reduction, employing Variational Auto-Encoder (VAE) within the Spark distributed framework. The deliberate selection of the "TLC" dataset, representative of New York City taxi trips with inherent high dimensionality, highlights the practicality of our approach. Our research showcases the virtuoso performance of VAE, achieving an impressive 95.12% reduction ratio and 89.26% accuracy. This highlights VAE's ability to elegantly distill essential information while discarding superfluous dimensions, achieving a harmonious balance between reduction and accuracy. Furthermore, building on the demonstrated superiority of Spark over Hadoop in prior successes, our adoption of VAE aligns with the overarching goal of enhancing big data processing. Spark's consistent advantage as a distributed framework reaffirms its reliability in handling diverse machine learning algorithms. This paper not only contributes to the advancement of machine learning in big data processing but also underscores the adaptability, versatility, and consistent performance of our approach across various methodologies and frameworks. The success of VAE in reducing dimensionality, coupled with Spark's inherent advantages, positions this research as a valuable contribution to the exploration of advanced techniques in distributed big data processing. [ABSTRACT FROM AUTHOR]

More than 20 years have elapsed since the September 11, 2001 (9/11) terrorist attacks on the World Trade Center (WTC), Pentagon and at Shanksville, PA. Many persons continue to suffer a variety of physical and mental health conditions following their exposures to a mixture of incompletely characterized toxicants and psychological stressors at the terrorist attack sites. Primary care and specialized clinicians should ask patients who may have been present at any of the 9/11 sites about their 9/11 exposures, especially patients with cancer, respiratory symptoms, chronic rhinosinusitis, gastroesophageal reflux disease, psychiatric symptoms, and substance use disorders. Clinicians, especially those in the NY metropolitan area, should know how to evaluate, diagnose, and treat patients with conditions that could be associated with exposure to the 9/11 attacks and its aftermath. As such, this issue of Archives contains a series of updates to clinical best practices relevant to medical conditions whose treatment is covered by the WTC Health Program. This first paper in the 14-part series describes the purpose of this series, defines the WTC Health Program and its beneficiaries, and explains how relevant Clinical Practice Guidelines were identified. This paper also reminds readers that because physical and mental health conditions are often intertwined, a coordinated approach to care usually works best and referral to health centers affiliated with the WTC Health Program may be necessary, since all such Centers offer multidisciplinary care. [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "Paper Tiger Television: smashing the myths of the information industry every week on public access cable," by Deedee Halleck, which appeared in "Cultures in Transition." It explores the history and strategies of the public access series within Paper Tiger Television Inc. in New York City. It discusses the series' view of the culture industry. It also examines how a publication covered in Paper Tiger is enmeshed in the transnational corporate world.

Background: In the U.S. there are significant racial and gender disparities in the uptake of pre-exposure prophylaxis (PrEP). Black Americans represented 14% of PrEP users in 2022, but accounted for 42% of new HIV diagnoses in 2021 and in the South, Black people represented 48% of new HIV diagnoses in 2021 but only 21% of PrEP users in 2022. Women who use drugs may be even less likely than women who do not use drugs have initiated PrEP. Moreover, women involved in community supervision programs (CSP) are less likely to initiate or use PrEP, More PrEP interventions that focus on Black women with recent history of drug use in CSPs are needed to reduce inequities in PrEP uptake. Methods: We conducted a secondary analysis from a randomized clinical trial with a sub-sample (n = 336) of the total (N = 352) participants from the parent study (E-WORTH), who tested HIV negative at baseline were considered PrEP-eligible. Black women were recruited from CSPs in New York City (NYC), with recent substance use. Participants were randomized to either E-WORTH (n = 172) an HIV testing plus, receive a 5-session, culturally-tailored, group-based HIV prevention intervention, versus an HIV testing control group (n = 180). The 5 sessions included an introduction to PrEP and access. This paper reports outcomes on improved awareness of PrEP, willingness to use PrEP, and PrEP uptake over the 12-month follow-up period. HIV outcomes are reported in a previous paper. Results: Compared to control participants, participants in this study assigned to E-WORTH had significantly greater odds of being aware of PrEP as a biomedical HIV prevention strategy (OR = 3.25, 95% CI = 1.64–6.46, p = 0.001), and indicated a greater willingness to use PrEP as an HIV prevention method (b = 0.19, 95% CI = 0.06–0.32, p = 0.004) over the entire 12-month follow-up period. Conclusions: These findings underscore the effectiveness of a culturally-tailored intervention for Black women in CSP settings in increasing awareness, and intention to initiate PrEP. Low uptake of PrEP in both arms highlight the need for providing more robust PrEP-on-demand strategies that are integrated into other services such as substance abuse treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT02391233. [ABSTRACT FROM AUTHOR]

Given that Ecuadorians are one of the largest groups of Hispanics living in New York, they have become a tight community that they now call little Ecuador. Although Ecuadorians living in the diaspora in NYC come from different parts of the country (mostly from the Andean region), they share the same cultural practices they performed in Ecuador that give them the sense of being in their country without bearing the instability and turmoil their country experiences. This shows how the group has fostered a sense of a multifaceted, multidimensional simultaneity between the host country and the motherland. The goal of this paper is to analyze the strategies Ecuadorian migrants use to validate their language and cultural practices to negotiate their identity as a group. Data for this paper come from ethnographic observations, semi-spontaneous conversations, oral interviews with members of the group, along with pictures taken while walking the community and participating in some of their events. Our study reveals that participants hold varying perceptions regarding their linguistic and cultural practices. However, it is noteworthy that they recognize these practices as a manifestation of Ecuadorianness, signifying a sense of solidarity among community members. [ABSTRACT FROM AUTHOR]

Copyright of Urban Studies (Sage Publications, Ltd.) is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The traditional air-assisted side-deep fertilization device has some problems, such as inaccurate control system parameters and poor precision in variable fertilization. It seriously affects the application and popularization of the device. Aiming at the above problems, this paper wanted to realize the precise fertilizer discharge control of an air-assisted side-deep fertilization device. This paper designs an electronically controlled fertilization system based on a PID controller from the past. The system model was constructed in MATLAB, and the mathematical model and transfer function model of a stepper motor, the mathematical model of fertilizer discharge, and the stepper motor rotational speed were established too. In order to improve the accuracy of precise fertilizer discharge control system parameters, the system parameters were optimized based on the particle swarm optimization algorithm and the control system tuner toolbox. We had established a validation test platform to test the performance of a precise fertilizer discharge control system. In the actual experiment, the maximum stability coefficient of variation was 0.91% at the target fertilizer discharge mass level of 350 g/min, and the maximum error of fertilizer discharge was 4.14% at 550 g/min of the target fertilizer discharge mass level. By analyzing the test results of the precise fertilizer discharge control system, the new precise fertilizer discharge control system had good fertilizer discharge stability and could also meet the technical specification for quality evaluation of fertilization machinery (NY/T 1003-2006). This research can improve the fertilizer discharge accuracy of the air-assisted side-deep fertilization control system. [ABSTRACT FROM AUTHOR]