Respiratory bioaerosol deposition from a cough and recovery of viable viruses on nearby seats in a cabin environment

Respiratory bioaerosol deposition in public transport cabins is critical for risk analysis and control of contact transmission. In this work, we built a two-row four-seat setup and an air duct system to simulate a cabin environment. A thermal manikin on the rear left-hand seat was taken as the infected passenger (IP) and “coughed” three times through a cough generator. The deposited viruses and droplets on nearby seats were measured by a cultivation method and microscope, respectively. The effects of seat backrest and overhead gasper jet were studied. Results showed that the number of deposited virus on the front seat was one order of magnitude higher than that on other seats which only contained droplets smaller than 10 µm in diameter. When the backrest was 15 cm higher than the cough, the deposited number of viruses was reduced to 5% of that with the backrest at the same height with the cough. The gasper jet above the IP with a velocity of 1.5 m/s can reduce the deposited viruses to 4% of that with gasper off. It indicates that both the gasper jet and backrest can work as mitigation measures to block the cough jet and protect the nearby passengers.     

Fame of Thrones: Seats,Sights, and Sanctity among the Inka

Abstract

The Inka of Andean South America regarded as sacred those seats reserved for the divine head of state. The most famous of such seats was known to the Inka as the Sapaqurinka; today it is more commonly known as the Throne of the Inka. It was hewn from a rock outcrop located atop a promontory overlooking the Inka’s capital city of Cuzco. Attending closely to its specific parts, as well as to its overall aspect, location, and medium, this paper elucidates the principles evoked when the Inka ruler sat on stone, saw what was there to be seen, and assumed the role of divine overseer. The petrous materiality of the Throne, its fixed location, and the ways in which it was carved, combined to enable the deific leader of the Inka state to become simultaneously a living ruler and an extension of the sacred landscape. By sitting, the Inka ruler not only inhabited a sacred topography, but merged with it, his body composed of vital but impermanent flesh and also – in deliberate complementarity – petrous fixity and permanence.     

连续大跨钢结构支座滑移监测研究及应用

论述超声传感监测系统的特点、功能和适用环境,针对某连续大跨钢结构工程支座滑移监测项目,介绍传感系统的布置,并对支座滑移监测数据进行深入分析。结果表明:支座滑移量随温度增加基本呈线性变化;受平面、立面呈曲线布置的结构形式的影响,同一位置处各支座的滑移量存在差异;结构的温度场不均匀及日照会对各支座滑移量产生影响;监测数据与结构理论计算结果吻合良好。采用超声传感系统进行大跨连续结构支座滑移监测的数据稳定性及可靠性好、精度高,完全适用于大型结构在自然环境下的位移监测。     

Housing the Urban Poor in 1800: Courts in Atherstone and Coventry,Warwickshire

Abstract

The character of the demolished houses in eighteenth- and early nineteenth-century court developments in Atherstone and Coventry has been established from a variety of sources. Typically they had one-room plans with one or two bedrooms upstairs and, in Coventry, sometimes a 'top shop' on a third floor. The living rooms in Atherstone had distinctive internal fittings, with a closed-off pantry, stair and coalhole at the rear. The houses in the Warwickshire courts were among the smallest examples of industrial housing recorded, though they did not include either single-room or cellar dwellings.     

Improving photovoltaic panel performance via an autonomous air cooling system – experimental and numerical simulations

ABSTRACT

The temperature rise of a PV panel during its functioning is known to induce losses of its performances. We propose to minimise these losses via a simple and autonomous air cooling system composed by a fan activated by the electricity produced by the panel. This fan blows ambient air on the rear face of the panel. Experimental measurements of the current intensity as well as voltage delivered by the panel and its front face temperature ensure the validation of the numerical code. Numerical and experimental results are in good agreement. As the main results of this autonomous cooling, when compared to the uncooled panel situation, the efficiency for harsh climatic condition increases of 29.52% while the panel temperature lowered of 39.29°C. Such results achieved with this quite simple autonomous cooling system on the improvement of the PV panel efficiency suggest interesting economic and commercial arguments.     

An Unusual Early Fifteenth-Century Scarf Joint in Pembridge,Herefordshire

Abstract

In volume 28 of Vernacular Architecture David and Barbara Martin identified a group of buildings in eastern Sussex that they interpreted as detached kitchens. Anything from two to four bays long, with at least two ground-floor rooms and two or more upper chambers, they 'closely resemble small houses.' It is often their location, close to the rear of a main house of more standard layout, which indicates the true function of these buildings. 'After houses and barns, detached kitchens were once the most common building type present in the landscape of south-east England ...' The authors suggested that surviving kitchens are likely to be the larger examples of their kind, and that many that have been lost were no more than single-story one-room outhouses. The cited examples were believed to date between 1450 and 1550.     

An experimental study of air quality inside large athletic halls

Air quality in two large athletic halls with different ventilation (natural and mechanical) was investigated in relation to outdoor pollution and meteorological conditions. Simultaneous measurements of O₃, NO, NO₂ and SO₂ were performed in the halls at two heights (at the arena and spectators’ seats) and outdoors. BTX concentrations at the spectators’ seats and outdoor NMHCs, CH₄, PM₁₀ and CO concentrations were also measured. Analysis of diurnal variations of the pollutants’ concentrations, cross correlation analysis of the concentration time-series and principal component analysis were applied to the collected data. Results revealed that outdoor pollution significantly affected indoor air quality of both halls. However, this effect was different for the two buildings, depending on the ventilation types, the wind direction prevailing at the areas and the kind of indoor activity recorded. It was found that the latter parameters controlled the pollutants concentration levels in the halls and their response to the changes of the outdoor pollution levels. Temperature and pollution stratification enhancing during athletic events were also evident in both halls but with different characteristics observed, such as the spatial distribution of the indoor pollutants. The airflow patterns prevailing in each hall, imposed by the ventilation operation schemes were important factors.     

Normalizing biproportional methods

Biproportional methods are used to update matrices: the projection of a matrix Z to give it the column and row sums of another matrix is R Z S, where R and S are diagonal and secure the constraints of the problem (R and S have no signification at all because they are not identified). However, normalizing R or S generates important mathematical difficulties: it amounts to put constraints on Lagrange multipliers, non negativity (and so the existence of the solution) is not guaranteed at equilibrium or along the path to equilibrium. Received: June 2001/Accepted: September 2001     

The mathematical model for steady magnetohydrodynamic flow between parallel porous plates with an angular velocity

ABSTRACT

The model is developed as the steady magnetohydrodynamic (MHD) flows with an angular velocity between parallel porous plates are considered. The problem is solved analytically by using similarity transformation, whose solution deals with increasing fluid flow with an angular velocity. The applications in MHD are power generators, polymer technology, cooling system, petroleum industry, aerodynamics heating used. The objective of this paper is to analyse the steady MHD flow of viscous fluid with an angular velocity between parallel porous plates when the fluid is being withdrawn through both the walls of the channel at the same rate. The problem is reduced to a third-order linear differential equation which depends on a Suction Reynolds number R and M ₁ for which an exact solution is obtained.     

On the idea of ex ante and ex post normalization of biproportional methods

Biproportional methods project a matrix A to give it the column and row sums of another matrix; the result is R A S, where R and S are diagonal matrices. As R and S are not identified, one must normalize them, even after computing, that is, ex post. This article starts from the idea developed in de Mesnard (2002) – any normalization amounts to put constraints on Lagrange multipliers, even when it is based on an economic reasoning, – to show that it is impossible to analytically derive the normalized solution at optimum. Convergence must be proved when normalization is applied at each step on the path to equilibrium. To summarize, normalization is impossible ex ante, what removes the possibility of having a certain control on it. It is also indicated that negativity is not a problem.Received: October 2002/Accepted: June 2003     

装载机工作装置微机控制系统的设计

本文探讨了以MC6E／32控制模块为核心的装载机工作装置微机控制系统。在分析控制目标的基础上，设计出系统的组成结构，利用电液比例减压阀作为先导阀改造原有的液压系统，使用效果表明该系统的设计合理、可行。     

Green Building Assessment Systems: A Framework and Comparison for Planners

Problem: Building assessment systems allow planners to examine whether buildings and developments meet sustainability goals, but no framework exists to help planners choose among them.

Purpose: This study develops a framework for planners to use in considering which building assessment system would be most appropriate for their purposes and analyzes nine such systems.

Methods: I conducted a content analysis of the system documentation for nine building assessment systems used in the United States and interviewed administrators of the systems.

Results and conclusions: Although many building assessment systems appear at first to be quite similar, they have substantial differences, and could produce significantly different results when used to implement green building programs. Among the important differences are the scales at which they consider various issues, whether or not they emphasize communication, and how they prioritize and weight concerns. I also found that most national building assessment systems lack a mechanism for adapting them to local concerns and conditions.

Takeaway for practice: While building assessment systems offer new tools to help communities meet sustainability goals, planners should consider the details of each system carefully before deciding on which to use in their communities. It would be very desirable for building assessment systems to become adaptable, so they will be more locally relevant and appropriate.

Research support: None.     

Numerical analysis on heat transfer characteristics of ionic liquids in a tubular heat exchanger

ABSTRACT

The efficiency of the solar thermal system depends on the performance of the solar collectors. There is a need to operate solar collector at higher possible temperature to attain maximum efficiency limits. However, the performance of the collector system is limited by the heat transfer characteristics of the working fluid called as the heat transfer fluid (HTF). Water is widely used as the HTF in the solar collector, but the major problem of using water as the HTF is its limited operating temperature. The objective of the work is to investigate the heat transfer characteristics of ionic liquids in tubular heat exchanger (HE) suitable for the solar thermal application. The HE was designed for a heat duty of 1?kW based on the thermal transport property of available ionic liquids and the computational fluid dynamics (CFD) analysis was performed. The results indicate that there is only minimal deviation between the assumed and CFD data.     

城市地下停车场系统等级划分研究——张家港购物休闲公园地下停车场系统

从城市交通规划的角度,地下停车场系统是解决城市停车问题的有效方法。地下停车系统的出入口和车道设置数量、出入口连接段交通组织方式等相关设计参数,都涉及到系统等级划分问题。结合地下停车系统的基地条件、停车总泊位数、停车单元数量等三项指标,提出了系统等级的划分方法,并以张家港购物休闲公园地下停车场系统为例,对其系统等级进行了研究。     

Statehouse Versus Greenhouse

Problem: In the absence of U.S. federal action to address the problem of climate change, a diverse array of nonfederal policy entrepreneurs and climate action planners has produced an impressive body of plans and policies to fight climate change at the regional, state, and local levels. Their actions are highly laudable, but have they actually reduced greenhouse gas (GHG) emissions?

Purpose: This article evaluates the work of a group of innovative state-level policy entre-preneurs whose actions were chronicled by Barry Rabe, and a set of 29 state climate action plans systematically analyzed by Stephen Wheeler. It compares states with and without climate policy entrepreneurs and states with and without climate action plans, asks if either plans or entrepreneurs have been successful in reducing CO2 emissions, and identifies the elements within plans that are associated with the greatest reductions.

Methods: The analysis uses multiple regression models to explain changes in per capita CO2 emissions attributable to residen-tial, commercial, transportation, and total nonindustrial end users from 1990 to 2007. A package of control variables accounts for political, social, climatic, economic, and urban form factors, while policy variables isolate the effects of climate policy entrepre-neurs, climate action planners, and specific policy recommendations within climate action plans.

Results and conclusions: State-level climate actions reduce GHG emissions by a measurable but modest amount: about one half metric ton per person per year. This represents 2–3% of the average American's 24-ton annual total GHG emissions. The reduction is small in comparison to the magnitude of the problem, but a substantial tax increase or population shift away from sprawling areas would be necessary to achieve the same reduction. specific policies I find to be associated with lower emissions include: building efficiency in both residential and commercial sectors, Leadership in Energy and Environmental Design (LEED) policies in the commercial sector, and California's vehicle efficiency standards in the transportation sector.

Takeaway for practice: It is encouraging that we can already identify emission reduc-tions related to state climate action. However, the observed reductions remain small com-pared to the scope of the problem. These findings should persuade states without plans to begin the planning process while encourag-ing states with plans to encourage more entrepreneurship aimed at developing a second generation of policy options for stabilizing our planet's climate with or without federal action.

Research support: None.     

Detached Kitchens in Eastern Sussex A Re-assessment of the Evidence

Abstract

It can be demonstrated that, after houses and barns, detached kitchens were once the most common building type present in the landscape of south-east England, yet today very few examples survive. Those which do mainly date from the period 1450-1550 and are surprisingly large and complex. They range in length from two to four bays and usually have more than one ground floor room and at least one, and often two or more upper chambers. Although all incorporate non-standard features, in general appearance the surviving examples closely resemble small houses. It is often only their location, close to the rear of a main house of more standard layout, which indicates their true function. Documentary evidence suggests that, in addition to the kitchen itself, the buildings housed such service rooms as bakehouses, and milkhouses. The upper chambers gave extra storage and accommodation.

It should be stressed that those kitchens which survive are likely to represent the larger, more elaborate examples. Many of those which have been lost may have been nothing more than single-roomed, single-storeyed outhouses. Yet the fact cannot be ignored that there would have been a considerable difference in status between those households with, and those without detached kitchens, despite the surviving houses being of similar size and layout. The importance of the detached kitchen in relation to vernacular studies should not be underestimated.     

不同影剧院座椅连排燃烧特性试验研究

利用10 MW 大尺度量热计对不同影剧院座椅进行连排燃烧试验研究。建立座椅燃烧试验台，将15 把影剧院座椅分3 排台阶布置，通过对多人影剧院软质座椅排列在一起进行燃烧试验，提供燃烧产生的热释放速率、总热释放量、产烟速率、总产烟量相关特性信息。试验中，分别选取普通影剧院座椅与阻燃影剧院座椅分别进行连排燃烧试验，并将燃烧测试得到的热释放速率、总热释放量等燃烧性能参数进行了对比分析，同时对火焰传播速度进行了计算。结果表明：同样点火方式条件下，普通座椅连排燃烧在8 min 内发生轰燃，热释放速率峰值高达9.204 MW，总热释放量为1 957.2 MJ，经阻燃处理后，热释放速率峰值为83.6kW，总热释放量为27.33 MJ，其他燃烧性能指标均显著下降；普通影剧院座椅连排燃烧时，火焰规模大，火焰扩散速度快，经计算火焰传播速度为0.65 m/min。     

液压挖掘机工作装置运动轨迹的智能化模糊控制

本文介绍用微机控制液压挖掘机作业运动的原理及工作原置,应用模糊控制算法,通过控制电液系统,使驱动元件的动作跟踪工作机构的运动,从而实现工作装置的运动轨迹控制。     

From the Subprime to the Exotic: Excessive Mortgage Market Risk and Foreclosures

Problem: The recent rapid growth of high-risk mortgage lending raised the financial risk profile facing not only the American homeowner but entire neighborhoods. From the perspective of planners, the problem of increased and geographically concentrated foreclosures is the most critical outcome that has resulted from high-risk mortgage markets.

Purpose: This article analyzes recent trends in mortgage finance in order to recommend what local planners can do to reduce the negative consequences of high-risk home lending for their own communities.

Methods: I plot public and private data, much of it readily available for little or no cost, to discover where in the nation recent mortgage foreclosures are concentrated, and describe how similar analysis could be used prospectively and at a local scale to anticipate future problems.

Results and conclusions: Numbers of subprime, exotic, and zero-down-payment mortgages have all been growing. Where they are spatially concentrated they are linked to rising and geographically concentrated home mortgage foreclosures. I find evidence that subprime lenders achieve greater market penetration in metropolitan areas with less educated residents, and that higher-risk lending is more prevalent where housing prices are high and increasing. I also find that when local housing markets are hot, even high levels of subprime lending are associated with only slightly higher foreclosure filing rates, but foreclosure rates rise quickly when hot markets cool.

Takeaway for practice: Although foreclosures are less likely to be a severe problem in very strong real estate markets, when prices in previously hot markets stagnate or decline, foreclosures can quickly follow. This is a serious concern given recent trends in mortgage financing that have extended credit to more economically vulnerable populations and generally weakening housing markets in many metropolitan areas. These foreclosures tend also to be spatially concentrated within metropolitan areas, particularly stressing housing markets in neighborhoods where the higher-risk products are more prevalent. I recommend that planners: (1) track local lending and foreclosure patterns; (2) promote healthier mortgage markets in vulnerable areas; (3) fund targeted foreclosure prevention and counseling; (4) develop refinancing/restructuring programs; (5) redesign programs to promote sustainable homeownership; (6) get foreclosed properties reoccupied quickly; (7) recognize the effect of foreclosure surges on rental housing markets; and (8) be proactive in policy debates on lending regulation and foreclosure processes.

Research support: None.