Search

On March 22, 2020, the State of New York issued a "stay-at-home" policy, wherein all non-essential businesses were on pause until June 8, 2020. The bike-sharing system (BSS) and yellow taxi system (YTS) in Manhattan were substantially affected. This sudden drop in demand can impact not only short and long-term mobility but also the sustainability of transport network. Given that few empirical studies are focusing on the impacts of the "stay-at-home" policy on the BSS and YTS, this further substantiates the importance of analyzing how the policy affects the overall transportation system in New York City (NYC). This paper aims to fill this gap by quantifying the impacts of the "stay-at-home" policy on the two aforementioned transportation systems. Specifically, the following three research gaps are summarized in this study: I) The hidden biases in current "stay-at-home" policy estimation methods were not properly addressed; II) The policy impacts on BSS and YTS during different periods of the effective day were unclear; III) The sensitivity of uncontrolled confounders in long-term policy impact estimations was poorly discussed. We addressed these important research gaps by introducing robust statistical approaches like regression discontinuity design (RDD) and propensity score matching (PSM) methods, which can overcome methodological challenges such as counterfactual restoration, spatiotemporal heterogeneities, and unmeasured confounders. The BSS and YTS were studied at the aggregated neighborhood levels. Results demonstrate that the impacts on BSS have higher variations than YTS usage. The monthly average treatment effects on the treated (ATT) for BSS ranged from −72% to −28% respectively in March and June, while YTS ranged from −96% to −94%. Evidence suggests that demand for BSS surged on weekends in May and June. Understanding the impact of this short-term yet significant policy change on travel behavior will help optimize supply and demand management strategies, thereby improving the long-term sustainability should similar situations arise in the future. • Quantifying the short-term and long-term impacts of the "stay-at-home" policy. • Data-driven approaches using regression discontinuity design and propensity score matching method. • The bike-sharing system and yellow taxi system have different sensitivities to the policy. • Policy implications are derived from the robust analyses. [ABSTRACT FROM AUTHOR]

Obstacle-avoiding rectilinear Steiner minimal tree (OARSMT) construction is an essential part of routing. Recently, IC routing and related researches have been extended from Manhattan architecture (λ2-geometry) to Y-/X-architecture (λ3-/λ4-geometry) to improve the chip performance. This paper presents an O(n log n) heuristic, λ-OAT, for obstacle-avoiding Steiner minimal tree construction in the A-geometry plane (λ-OASMT). In this paper, based on obstacle-avoiding constrained Delaunay triangulation, a full connected tree is constructed and then embedded into λ-OASMT by zonal combination. To the best of our knowledge, this is the first work addressing the λ-OASMT problem. Compared with most recent works on OARSMT problem, A-OAT obtains up to 30-Kx speedup with quality solution. We have tested randomly generated cases with up to 10 K terminals and 10-K rectilinear obstacles within 4 seconds on a Sun V880 workstation (755-MHz CPU and 4-GB memory). The high efficiency and accuracy of λ-OAT make it extremely practical and useful in the routing phase. [ABSTRACT FROM AUTHOR]

This paper draws on 49 qualitative interviews to explore the contextual antecedents of methamphetamine use in a sample of gay and bisexual Manhattan men. The paper distinguishes itself from the public health literature on crystal methamphetamine use in this population by shifting the analytic focus from individual‐level factors of drug use to the role of social context. While individual‐level factors—including self esteem and social awkwardness—are related to methamphetamine use, we argue that these factors arise in and are exacerbated by interactional pressures attendant to Manhattan's gay sexual subculture, which revolve around the expectation of peak sexual performance. Because methamphetamine is associated with increased self‐esteem, increased libido, greater sexual endurance, diminished sexual inhibition, and a higher threshold for pain, the drug is used strategically by gay and bisexual men to negotiate sexual sociality and increase sexual pleasure. Hence, we suggest that there exists an elective affinity between Manhattan's gay sexual subculture and the particular pharmacological effects of methamphetamine—whereby the former strongly favours the latter as a systematic pattern of response. In turn, this relationship is linked to unsafe sexual practices or the social conditions that put gay men ‘at risk of risk’ of HIV infection. [ABSTRACT FROM AUTHOR]

This paper considers two planar facility location problems while employing the Manhattan travel metric. We first consider the p-median problem in the presence of arbitrarily shaped barriers and convex forbidden regions. For this problem we establish that the search for an optimal solution can be restricted to a finite set of easily identifiable points. Next, we consider the stochastic queue median problem in the presence of arbitrarily shaped barriers. A procedure to obtain a global optimum solution for this problem is established. The results of the paper are illustrated via numerical examples. Finally, we comment on a connection between network location problems and planar location problems which use the Manhattan travel metric. [ABSTRACT FROM AUTHOR]

• Optimal risk-informed participation strategies of producers depend on T&D coordination schemes. • Sequence of Gate Closure Times for wholesale and distribution markets introduces uncertainty in the profit of the strategic producer. • Regulated distribution environment is the most lucrative setting for strategic producers to maximize profits without risk exposure. • Sequential market-clearing model reduces the profit of strategic producer as compared to joint market-clearing model. • Incorporation of CVaR for quantifying risk renders the strategic producer more risk-averse at the expense of reduced profits. Power producers can exhibit strategic behavior in electricity markets to maximize their profits. This behavior is more pronounced with the deregulation of distribution markets, which offers an opportunity for profit arbitrage between transmission and distribution (T&D) markets. However, the temporally distinct nature of these two markets introduces a significant risk in profit for such producers. This paper finds its motivation from the perspective of a strategic producer and develops a Single Leader Multi-Follower (SLMF) game for deriving its participation strategies in T&D markets, while accounting for different T&D coordination schemes based on the individual market Gate Closure Times (GCT). We compare and contrast joint and sequential market-clearing models with regulated and deregulated distribution environments and evaluate the risk of producer by leveraging consistent and coherent risk measures. SLMF game is reformulated as a Mathematical Program with Equilibrium Constraints (MPEC) and is solved using the seminal Scholtes's relaxation scheme. We validate the efficacy of our model and solution approach via the case study carried out on the 11-zone New York ISO, and 7-bus Manhattan power networks, used as T&D markets, respectively. [ABSTRACT FROM AUTHOR]

Struening et al. demonstrated a widening disparity of low birthweight (LOB) rates among New York City health areas from 1980-1986, clearly a dynamic process. In contrast, the New York City Department of Health reported static citywide LOB rate in 1988-2008. Struening et al. is extended here at the health district level with mapping and regression analyses. Additionally, birthweight data are reported for babies born in 1998-2001 to a group of African-American and Dominican women in Upper Manhattan. The data reported in this paper indicate that both fetal programming of the mother herself (life course model) and stress during or shortly before pregnancy may play a role in LOB. Current stress may arise from past events. Intergenerational effects, thus, could arise from stresses on the grandmother and their residual impacts on the mother as well as new stresses on the mother as an adult. The average weight of babies born to the Upper Manhattan mothers who were born in 1970-1974 was 3,466 g, with 1.6% below 2,500 g; that of babies of mothers born in 1975-1979, 3,320 g, with 6% below 2,500 g. The latter group was born during the 1975-1979 housing destruction. Intergenerational impacts of that event may be reflected in this elevated rate of LOB. Health district maps of LOB incidence ranges show improvement from 1990-2000 and then deterioration in 2005 and 2008. Bivariate regressions of socioeconomic (SE) factors and LOB incidence showed many strong associations in 1990; but by 2000, the number and strength of these associations declined. In 1990, 2000, and 2008, black segregation was the SE factor most strongly associated with LOB. Black segregation and murder rate explained about 85% of the pattern of 1990 LOB. Regressing the 1970-1980 percent population change against the SE factors showed effects even in 2000. The 1990 murder rate and 1989 percentage of public assistance explained over half the 2008 LOB incidence pattern. The housing destruction of the 1970s continued to influence LOB incidence indirectly in 2008. The ability of community and individual to cope with current stressors may hinge on resilience status, which is shaped by past events and circumstances. The present interacts with the past in many ways. Serial displacement exemplifies this interaction of immense importance to public health. [ABSTRACT FROM AUTHOR]

The unprecedented toxic release in lower Manhattan on September 11, 2001 created one of the worst environmental disasters in US history, followed by a contentious and ongoing battle over the existence, etiology, and legitimation of World Trade Center-related illness. In this paper, I explore the enactment of epistemic authority by a complex array of stakeholders-government officials, scientists, physicians, environmentalists, advocates, journalists, and politicians-who have woven medical-scientific knowledge into their competing agendas and platforms. Despite the scientific validation of environmental dangers, the clinical documentation of illness and the epidemiological substantiation of links between environmental exposure and illness onset, the political-economic interests of federal, state, and local bodies have often been privileged over the protection of public health. 9/11 illness is a 'contested illness' enmeshed in politically charged disputes regarding the relationship of environmental toxins to disease. [ABSTRACT FROM AUTHOR]

The Manhattan Midtown-2005 field experiment (MID05) collected turbulence observations at 12 street-level sites (at 3-m height) and at 5 rooftop sites (at 220-m average height). The MID05 observations of 30-min averaged standard deviations of wind speed components and temperature and of sensible heat and momentum flux are found to be consistent with the authors’ previously reported averaged observations in similar tall-building surroundings in the Oklahoma City Joint Urban 2003 (JU2003) and Manhattan Madison Square Garden 2005 (MSG05) field experiments. The main focus of this paper, though, is on the magnitudes of the space and time variations of the 30-min averaged turbulence values. Wind tunnel experiments and computational fluid dynamics model outputs would suggest large variations, but the full-scale urban observations show that the standard deviations of the space and time variations are usually less than 50% of the averages. Some individual observations are tabulated and the minimum and maximum listed, showing a typical range at street level for, say, συ of about ±10%–20% in time and about ±40% in space. It is suggested that the reason for the observed lack of large variations in turbulence is the large amount of mixing generated by (i) the 20°–40° meanders in wind direction over the 30-min periods, which cause a “flopping” of building wakes, and (ii) the strong vertical mixing around the tall buildings. [ABSTRACT FROM AUTHOR]

Along East Broadway in Manhattan's Chinatown, many homes and businesses, once predominately those of Cantonese-speaking immigrants from Hong Kong and South China, are being replaced by those of recent arrivals from the Fuzhou region of Fujian Province—a province on China's south-east coast just north of Guangdong. A local New York industry has arisen to cater to the ritual needs of the Fuzhou emigré population. Within a single block of East Broadway, four businesses, advertising themselves as ‘flower shops’ ( huapu or huadian ), compete with one another to provide ritual services, paraphernalia, and personnel for events of social significance. This paper explores ways in which the ‘flower shop’ industry creatively fashions new traditions and why the people to whom it caters—the Fuzhou people—find a greater need for traditionalist activity than do their neighbours, the Cantonese. [ABSTRACT FROM AUTHOR]

The Cathedral Church of Saint John the Divine is the third largest church structure in the world. It is located on the upper west side of Manhattan in New York City. A fire in December of 2001 badly damaged the stonework of the unfinished north transept and spread thick black smoke through the entire building. After the fire, a comprehensive investigation was undertaken to identify the unique characteristics of the fire soil and then to use that information to determine the extent to which these materials had deposited on surfaces in the building. A direct correlation was made between the materials of construction that burned during the fire and the particles present in samples of soiling removed from throughout the Cathedral. It was therefore possible to establish that the fire soil had penetrated to all areas of the Cathedral and that all surfaces required cleaning. This paper describes the techniques used to carry out the investigation. [ABSTRACT FROM AUTHOR]

This paper examines the cocaine-violence relationship among samples of male and female street drug users using volume of cocaine use as the primary independent variable. Data derive from two ethnographic studies undertaken on the Lower East Side of Manhattan. Subjects were studied as both perpetrators and victims of violence. The research was guided by a tripartite conceptual model of the general relationship between drugs and violence. A number of significant differences between males and females are identified and discussed. These findings, together with those of a previous analysis of the relationship between frequency of cocaine use and violence, provide evidence of the complexity of the drugs-violence relationship in general, and cocaine-violence relationships specifically. [ABSTRACT FROM AUTHOR]

Information about the papers discusses in a special conference on "The Religious-Secular Divide: The U.S. Case" held at the New School for Social research in Manhattan on May 5 and 6, 2009 is presented. Topics include the origins of the secular, the influence of Immanuel Kant on modern secularism and secularism as ideology. Feature speakers include Noah Feldman, George Kateb and Richard J. Bernstein.