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Due to the high consumption of resources and energy in the construction sector, the development of resource-efficient and sustainable construction solutions is gaining increasing attention. The awareness of sustainability and resource conservation results in the interest of using natural and renewable materials in contemporary architecture. Timber construction methods offer both constructive and ecological potential for sustainable solutions. From a building physics perspective, the acoustic performance of lightweight buildings, such as those made of timber, presents a challenge. Even if standard requirements are met, the increased low-frequency sound transmission typical for light-weight construction can cause discomfort and is already the subject of questions in building physics, which are currently increasingly extending to timber construction. Within the framework of a holistic approach, this paper compares the problem of acoustic properties, design optimizations and the ecological properties of timber-frame and solid timber construction components. The comparison with heavy materials, such as concrete, shows the relation of acoustic optimization with the change of the environmental profile. In order to establish the interaction between acoustic quality of wooden ceiling constructions and their ecological characteristics, this article aims to demonstrate the potential of materials used in the building sector under ecological aspects considering a life cycle analysis., Deutsche Forschungsgemeinschaft

According to the few researches on Nearly zero energy residential buildings (NZERB) in hot-summer and cold-winter zone, although it could reduce the cooling load of buildings due to its high thermal insulation and air tightness, it still needed for certain cooling in summer. This paper studied indoor environment of NZERB under three kinds of air-conditioners (split-type air-conditioner, multi-line air-conditioner and ceiling radiant air-conditioner). Firstly, a simulation model of NZERB was established based on Nanjing, a typical city in hot-summer and cold-winter zone. Secondly, variation of indoor air temperature and building load characteristics with outdoor air temperature were studied. Thirdly, indoor environment and energy consumption under three selected conventional air-conditioners in summer were simulated. Finally, the discussion was given, and an air-conditioner combining with convective and radiant cooling were proposed. The results indicated that the air-conditioner needed to be turned on in NZERB in hot-summer and cold-winter zone due to the room air temperature in off-air condition ranged from 32 °C to 36 °C, which was higher than designed indoor environment temperature in summer, but the indoor environment of NZERB under three selected conventional air-conditioners could not meet the requirements of energy saving and comfort at the same time, and a proposed convective-radiant air-conditioner could be fast, stable, and energy saving. The findings can provide a reference for conducting active technology in NZERB.

It matters greatly for individuals, organizations and societies whether particular groups are disadvantaged for attaining management positions. Low social class origin is a likely candidate for suc...

This review investigated whether ceiling effects on client-reported working alliance measures represent measurement artifacts or valid information related to the formation of the working alliance. Using data from two previously published meta-analyses, a total of 92 estimates of ceiling effects were calculated based on 37 studies with 6,439 participants. Analyses examined the size of ceiling effects, relation with demographic variables, type of alliance measure, and ceiling effect stability across sessions. Moderate to large ceiling effects appeared across score distributions of multiple measures of client-rated alliance, across time administered, and across different sample characteristics such as gender, age, and ethnicity. When examined with the Session Rating Scale (SRS), analyses indicated ceiling effects had a moderate correlation with session number. When SRS ceiling effects were examined in a single study with a large sample of complete cases (N = 2,990) across seven sessions, large initial ceiling effects continued to increase slightly in size across sessions. Higher ceiling effects were also observed with the Working Alliance Inventory. Given the prevalence and relative stability of ceiling effects on score distributions, working alliance scores do not exhibit the characteristics of a normally distributed continuous variable. While the working alliance has typically been defined in terms of theoretical content such as tasks, goals, and bond, study findings suggest another key element may be a threshold structure where clients shift to an experience of the therapeutic relationship as established. Discussion focuses on directions for alliance research and clinical practice as well as study limitations. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Aims The main objective of this study was to examine whether the Oxford Shoulder Score (OSS) demonstrated floor or ceiling effects when used to measure outcomes following shoulder arthroplasty in a large national cohort. Secondary objectives were to assess its pain and function subscales, and to identify independent predictors for patients achieving a postoperative ceiling score following shoulder arthroplasty. Methods Secondary database analysis of the National Joint Registry (NJR), which included 48,270 patients undergoing shoulder arthroplasty, was conducted. The primary outcome measure was the OSS. Secondary outcome measures were the OSS-Function Component Subscale and OSS-Pain Component Subscale. Floor and ceiling effects were considered to be present if > 15% of patients scored either the lowest or highest possible score. Logistic regression analysis was used to identify independent predictors for scoring the highest possible OSS score postoperatively. Results Preoperatively, 1% of patients achieved the lowest possible OSS score (0) and 0.4% of patients achieved the highest possible score (48). Postoperatively, < 1% of patients achieved the lowest score at all timepoints, but the percentage achieving the highest score at six months was 8.3%, at three years 16.9%, and at five years 17%. Male patients, those aged between 60 and 89 years, and those undergoing an anatomical total shoulder arthroplasty (ATSA) were more likely to contribute to the ceiling effect seen in the OSS questionnaire. Pain and function subscales exhibited greater ceiling effects at three years and five years when compared with the overall OSS questionnaire. Logistic regression analysis showed that sex, procedure type, and preoperative OSS score were independent predictors for scoring the highest possible OSS at years. Conclusion Based on NJR patient-reported outcome measures data, the OSS does not exhibit a ceiling effect at six months, but does at three years and five years, in part due to outcome scores of ATSA. Preoperative OSS, age, male sex, and ATSA are independent predictors of achieving a ceiling score. Cite this article: Bone Joint J 2021;103-B(11):1717–1724.

Objectives: COVID-19 patients thought unlikely to benefit from organ support, thereby having a ward-based ceiling of care (WBCoC), represent a distinct subgroup. There are no associated studies in mortality. We sought to identify clinical risk factors for inpatient COVID-19 mortality. Design and setting: this was a retrospective observational study of patients admitted to Northumbria Healthcare NHS Foundation Trust. Clinical variables were associated with inpatient mortality via logistic regression. Participants: all patients admitted with COVID-19 infection and who had a WBCoC at point of admission were included (n = 114). Main outcome measures: the outcome measure was inpatient death.

The present work investigates the benefits and challenges of applying surface guided radiation therapy (SGRT) to breast cancer treatments on the Halcyon™ (Varian, USA). Inter-fraction setup accuracy and treatment time were assessed by comparing CBCT shifts registered following SGRT-based vs. standard tattoo-based patient setup in two randomly selected groups of ten breast patients. Next, using a torso phantom and a volunteer, intra-fraction motion tracking accuracy and surface coverage were assessed for 3 adjusted central ceiling camera positions. SGRT was shown to significantly reduce setup errors (mostly within ± 2 mm) compared to tattoos (up to 2.1 cm) in all translational directions (p-value p = 0.038). Meanwhile, intra-bore surface coverage with an adjusted central SGRT camera proved insufficient, suffering from patient self-occlusions (invisible body parts occluded by patients’ own morphology such as breasts, bellies, arms, etc.) and bore-induced camera obstructions. Tracking accuracy remained satisfactory (sub-0.5 mm) but 6 degrees-of-freedom motion monitoring, critical in stereotactic radiosurgery, stereotactic body radiation therapy and deep inspiration breath hold techniques and clinical applications, was not possible. Standard ceiling-mounted SGRT systems reduce inter-fraction breast setup errors and treatment duration while intra-fraction motion tracking is insufficient for O-ring linear accelerators.

Iwahiko Tsumanuma (also known as Thomas S. Rockrise) was among the earliest immigrants from Japan to come to the United States to study architecture, and in the early twentieth century he established a successful practice, first in New York City and later in Asia. However, despite his training at Syracuse University in the conventional Beaux-Arts architectural vocabulary of the period, Tsumanuma found that the expectations of white patrons required that he design objects and spaces around Orientalist themes in the language of Japonisme. In Practicing Architecture under the Bamboo Ceiling: The Life and Work of Iwahiko Tsumanuma (Thomas S. Rockrise), 1878–1936, Gail Dubrow and collaborators Christina M. Rockrise, Alyssa Gregory, and Sarah Pawlicki make use of a previously unavailable archive of Tsumanuma's family papers to document the architect's life and career, presenting an in-depth case study of the multiple ways in which racism shaped the lives and experiences of Japanese immigrant architects in the United States in the early twentieth century. The methods used for this investigation, which included consulting family papers and collaborating with family descendants, provide a model for scholars seeking to better understand racism's formative role in shaping the history of the architectural profession.

Hydrogen jet fires from a thermally activated pressure relief device (TPRD) on onboard storage are considered for a vehicle in a naturally ventilated covered car park. Computational Fluid Dynamics was used to predict behaviour of ignited releases from a 70 MPa tank into a naturally ventilated covered car park. Releases through TPRD diameters 3.34, 2 and 0.5 mm were studied to understand effect on hazard distances from the vehicle. A vertical release, and downward releases at 0°, 30° and 45° for TPRD diameters 2 and 0.5 mm were considered, accounting for tank blowdown. direction of a downward release was found to significantly contribute to decrease of temperature in a hot cloud under the ceiling. Whilst the ceiling is reached by a jet exceeding 300 °C for a release through a TPRD of 2 mm for inclinations of either 0°, 30° or 45°, an ignited release through a TPRD of 0.5 mm and angle of 45° did not produce a cloud with a temperature above 300 °C at the ceiling during blowdown. The research findings, specifically regarding the extent of the cloud of hot gasses, have implications for the design of mechanical ventilation systems.

Earth has been used as a material for the building in the form of red bricks, sand mortar, mud floors, and lime sand ceiling since the earlier civilization of mankind. Due to its numerous climatic ...

Research on "Study of the rate ceiling Occupant Comfort House Live" aims to determine the appropriate standard ceiling height for the convenience of residents, to determine the effect of color on the comfort level of the household, to find a good material used for the ceiling of the house. The research was conducted by means of surveys, and the distribution of questionnaires to residents live to be studied, namely residents living that has a high ceiling, low, and medium. To achieve these objectives, the research methods used to study "Ceiling Study on Occupant Comfort Level House Live", namely: Observation is one of the methods of data collection techniques that not only measures the attitudes of respondents (interviews and questionnaires), but also can be used to record a variety of phenomena that occur (situation, condition). Questionnaire/ questionnaire was conducted data collection techniques by providing a set of questions or statements to others as respondents to answer. Research using this research tool gauges is distance meter ceiling height. Literature is a data collection technique in which researchers collected data on the theoretical basis associated with the object examined

In this study, which is the first of its kind in the gulf region, eye doses of interventional cardiologists and nurses were measured using active dosimeters for left and right eyes, in 60 percutaneous coronary interventions in three main hospitals in Kuwait. The dose given in terms of Hp(0.07) per procedure when ceiling suspended screens were used by main operators ranged from 18.5 to 30.3 µSv for the left eye and from 12.6 to 23.6 µSv for the right eye. Taking into account typical staff workload, the results show that the dose limit of 20 mSv/year to the eyes can be exceeded for interventional cardiologists in some situations, which demonstrates the need of using additional effective radiation protection tools, e.g. protective eye spectacles, in addition to the regular and proper use of ceiling suspended screens. With indications of increase in workload, the need for availability of a dedicated active dosimeter for the regular monitoring of eye doses is emphasized.

The air layer between the interior finishes and the structure is used as piping and wiring space. In many cases, ceilings and dry-type double floors are commonly constructed in Japan. However, the effect of the air layer of ceilings and dry-type double floors on the heavy-weight floor impact sound insulation performance has not yet quantitatively investigated. Therefore, in this study, the same floor and ceiling structures were constructed for concrete and CLT buildings, and the heavy-weight floor impact sound was investigated. As results, it was confirmed that the reduction amount of the heavy-weight floor impact sound by the ceiling tended to be smaller in CLT buildings than in concrete buildings. However, the trends were similar. Due to the dry-type double floor structure, the heavy-weight floor impact sound level was increased in concrete building and decreased in CLT building at 63 Hz in the octave band center frequency band. Therefore, it can be said that the dry-type double floor structure can be used to improve the heavy-weight floor impact sound performance in the CLT building.

Mosque is a building type used by Muslim people consists of speech and music rituals. Good acoustical condition in mosques is an important issue to provide desired acoustical environment for prayers and Imams during different worship rituals. Prayers need to feel individuality in praying and the sense of unity in recitation of the Quran, hymns. Worship activities need a high level of speech intelligibility and to satisfy prayers in the spiritual aspects which make people feel closed to the God. In the context of study, six historical mosques in Turkey, with different types of cover structures and plan typologies, are designated as study areas. The present study contains two methods which the first one is collecting acoustical data by measurements and the second consists of mathematical modelling software program. The purpose of study to investigate effects of different plan typology and ceiling structures on acoustical characteristics in mosques with similar volume. Also, distribution of acoustical parameters and the suitability of the values obtained through acoustic simulations and measurements to the recommended values are aimed to be investigated. As a result of the investigations, it was concluded that the objective acoustic parameters of mosques changed according to the geometric parameter properties.

Attenuation of sound transmitting between rooms oriented over one another inside buildings is studied. Transmission loss and sound transmission class were measured by an independent, accredited, acoustics laboratory with and without a variety of modular acoustic ceilings suspended under a baseline concrete floor structure. Ceiling panel material types include stone wool, fiberglass and mineral fiber. Ceilings were tested with and without the presence of service penetrations for supply air diffusers, return air grilles and light fixtures. Some ceilings were also scanned with a sound intensity probe and the resulting color sound maps are used as a supplemental method of evaluating both isolation and absorption performance of the individual components of the ceiling systems. Results show that while the effects of ceiling panel type on absorption performance, and thus room acoustics, is substantial, the material type and weight of the ceiling panels do not substantially affect the overall isolation performance of the floor-ceiling assembly.

Arkansas has been a popular place to study the effects of rate ceilings because of its exceptionally low interest rate ceiling. This paper examines the effects of the Arkansas rate ceiling on credit use by risky nonprime Arkansas consumers, which are especially vulnerable to credit rationing because of the low ceiling. We compare the level and composition of consumer debt of nonprime consumers in Arkansas with that of prime Arkansas consumers and also nonprime consumers in the neighboring states. We find that nonprime Arkansas consumers are less likely to have consumer debt and, conditional on having debt, have lower, but not much lower, levels of consumer debt than prime Arkansas consumers and nonprime consumers in neighboring states. Types of credit used by nonprime Arkansas consumers tend to differ from those of our comparison groups. Notable is much lower use of consumer finance loans, traditionally an important source of credit for higher risk consumers. This finding suggests rate-based rationing of risky consumers. Also notable is lower use of bank credit despite federal preemption of the rate ceiling for banks. This result is consistent with banks’ traditional avoidance of risky lending.

Roadway tunnels often include a reinforced concrete drop ceiling that is hung from the liner to create a plenum that facilitates ventilation and houses utilities. Drop ceiling panels are lightweight compared with the much thicker tunnel liner and can experience significant damage from a fire on the roadway below. This paper examines the flexural response of drop ceiling panels in two representative tunnels to standard fire curves as well as several realistic fires due to vehicular accidents. Standard fire demands as per the Rijkswaterstaat and ASTM E1529 fire curves are uniformly applied to the ceiling panels, and heat exposure contours for typical vehicle fires with heat release rates of 30, 100, and 200 MW are generated from the software CFAST. The finite element analysis software SAFIR is used to evaluate the thermo-mechanical behavior of the ceiling panels when subjected to various thermal demands from the fire below. The analysis results indicate that drop ceiling panels are highly vulnerable to fire-induced damage and potential collapse both during a fire’s active heating phase (from simultaneous loss of capacity and restraint of thermal expansion) and during the subsequent cooling period (from tension that develops when the permanently deformed panel thermally retracts). The potential for fire-induced damage or collapse of the drop ceiling panels can be mitigated by reducing the fire hazard, removing the drop ceiling, or enhancing the fire resistance of the panels via the application of passive protection or structural hardening.

Ceiling gas temperature rise is an important evaluation indicator determining the level of risk in a subway tunnel fire. However, very little literature has been found that has addressed the emergency when a fired subway train with lateral multiple openings stops in the interval tunnel. Hence, a battery of full-scale numerical simulations were employed to address the impact of train fire location on the gas temperature beneath the train ceiling. Numerical results showed that the ceiling gas temperature rise is affected by the pressure difference on both sides of fire source and the backflow from the end wall, which depends on the heat release rate and the fire location. The ceiling gas temperature rise decays exponentially in the process of longitudinal spread, and it can be predicted by a dimensionless model with a sum of two exponential equations. Finally, based on a critical fire location (L cr ⋆ = 0.667), two exponential equations were developed to quantitatively express the influences of the fire size and the fire location on the maximum ceiling gas temperature. The research results can be utilized for providing an initial understanding of the smoke propagation in a subway train fire.

This paper examines young women university students’ expectations of gender inequalities in the workplace, drawing upon semi-structured interviews with 21 young women at three mid-high ranking univ...

The comfort and safety of a house is the dream of any home owner, even a house that has a modern security system will be more in demand than a house with an ordinary security system. By utilizing existing technology, it is possible to create an excellent security system from theft and fire. In order to overcome these problems, a prototype of a security threat detection system was made using telegrams based on the internet of things. This can minimize the inconvenience of home owners when they are not at home in a long time, such as the owner of the house going out of town or abroad. The design of this smart home uses the NodeMCU ESP8266 Wifi Module as a controller, the telegram application as a notification when an unknown person opens a door or window, and when a fire occurs. The sensor used to detect the security of burglars is a Magnetic Door Switch, this sensor is placed on doors and windows. The sensor used to detect fire indications is the Flame Sensor which is placed on the ceiling of the house

Class may be the ultimate English taboo. Not long ago, the Labour Government minister John Prescott’s television documentary (2008) portrayed the UK as a country in which the very word was losing m...

Effective autonomous indoor flight requires an ability to sense and navigate ground, ceiling, and walls. While this can be accomplished in many ways including vision, one bio-inspired approach that is not well studied uses the detection of pressure changes when flying close to surfaces. As an example, an increase in pressure can be detected when a quadrotor flies close to the ground, a phenomenon known as ‘ground effect’. This work evaluates the viability of differential pressure measurements as a means of sensing ground, ceilings, and walls for small quadrotors. Extending existing models for thrust in ground effect, a model is derived to predict pressure changes due to ground effect in hover and tilt. The pressure response with ground effect is characterized across a range of distances, thrust levels, sensor locations, and quadrotor tilts using a Crazyflie 2.0 quadrotor and a small MEMS differential pressure sensor. Characterization experiments are also used to evaluate pressure measurements at varying distances from ceilings and walls, as well as the pressure behavior due to step changes in ground height. Manually controlled free flight tests are used to validate ground sensing in both nominal and visually challenging environments, as well as wall sensing in free flight.

Based on a case study of the undersea metro interval tunnel, this study proposes a model to evaluate the Ventilation and Smoke Exhaust System (VSES). In the VSES experiments, data of fan frequencie...

Salah satu risiko yang terjadi pada proyek konstruksi bersumber dari aspek keselamatan dan kesehatan kerja. Oleh karena itu perlu dilakukan identifikasi terhadap risiko yang mungkin terjadi dan menentukan pengendalian agar risiko tersebut bisa diminimalisasi. Penelitian dilakukan pada proyek konstruksi gedung pada pekerjaan struktur dan arsitektur. Dari penelitian yang telah dilakukan, terdapat 36 risiko yang berada pada tingkat prioritas 1 yang menyebabkan dampak kematian dan cedera permanen, prioritas tingkat 2 sebanyak 20 risiko yang masuk dalam kategori sedang, dan prioritas tingkat 3 sebanyak 26 risiko yang masuk dalam kategori rendah dan ringan. Adapun urutan prioritas utama pekerjaan yang harus dikendalikan adalah pekerjaan dinding dan plat lantai dasar basement, pekerjaan atap, pekerjaan dinding, pekerjaan dinding dan kolom struktural, struktur beton bertulang pondasi dan lantai, pekerjaan railing, struktur kolam renang, pekerjaan plafond, dan pekerjaan pintu jendela. Risiko-risiko tersebut dikendalikan dengan rekayasa teknik dengan metode kerja yang baik, mengatur jalur listrik, bekerja dengan penerangan yang baik, melakukan pengecekan berkala pada instalasi listrik dan alat, APK dengan memberikan rambu peringatan, APD dengan menggunakan sepatu kerja, helm, sarung tangan, safety belt, sepatu kerja.

Ceiling fans are the most common equipment in any household with electricity to induce a higher air movement since the potential of natural ventilation is limited. However, the higher airflow region is generally limited to the zone below the fan. The non-uniform distribution of airflow is also affected by the furniture layout and airflow from window openings. This study attempts to evaluate the effect of the different window-opening patterns on the airflow inside naturally ventilated bedrooms, having a ceiling fan for air movement with numerical simulations and on-site measurements. The airflow pattern created by a ceiling fan in a room with furniture is modelled and simulated with ANSYS Fluent 2019 R3. The results were validated with on-site measurements and compared with the literature. The air velocity was measured in bedrooms of three different sizes. It was observed that the opening of windows created a better distribution of air irrespective of room size. The non-uniformity of the air velocity is reduced from 76% to 39% with the opening of windows in the larger-sized room. The reduction in non-uniformity is influenced by the location of windows also. The practice of opening windows along with the induced air movement by ceiling fans results in a better distribution of air in the space. Practical application: People tend to depend mainly on ceiling fans even if windows are open in naturally ventilated rooms. A study of patterns of non-uniform distribution of airflow can help designers to improve comfort conditions by specifying the number and location of fans and windows while designing room furniture layout. This aids the building services engineers to provide thermal comfort without always depending on alternative active ventilation strategies.

In this study, radiant cooling panel is designed for a classroom. An arrangement is made such that the panels cover 70% of ceiling area. For study case a classroom is considered which need 27 such panels for covering 70% of area. The arrangement of panels, water flow rate, required temperature and amount of heat transfer taking place through panels is discussed in the paper. A cooling system is selected for maintaining the desired water temperature. Comparison is done between the cooling systems and the user can use any of them according to the requirements and cost. This system does not use any refrigerant hence it is environment friendly and can add a considerable solution to maintain temperature of a specific area. CFD analysis of the panel shows that adequate heat transfer takes place between panel and the room, this validates the design. When 15 ºC water is given as inlet to the panel, we get 22 ºC water as output at outlet of panel. In this paper, analysis is done for single panel same can be done for entire arrangement of panel structure.

The 492 Mogao Caves of Dunhuang, China, contain beautiful paintings dating back over 1500 years. Mogao Cave number 249 is especially stunning for its ceiling paintings of exploding volcanos, billowing smoke and steam, blue sky with white cloud racks, swans in flight, hunters riding horses, deer running amidst exploding volcanos, a pouncing tiger, a stalking lion, a prancing bull, a winged horse, men riding dragons, and human-dragon hybrids soaring through smoke and clouds. A distinct stylistic painting technique of repetition appears in the ceiling in different forms. In one form, a whole figure appears in multiple stages of one movement: for example, one man riding a dragon across the sky appears in three places on the same panel, on the same skyline, in succession; but the positions of the dragon’s wings and overall form and the surrounding clouds vary. In another form of the technique of repetition, one part of a body is repeated in successive overlaying images: for example, a human-dragon hybrid appears with nine heads fanned (like playing cards) along the back of the dragon, the whole head at the front of the dragon, and that head overlaying most of the one behind it, and that one then overlaying most of the one behind it, and so on, to the ninth along the back of the dragon. This same image (and the same technique) appears on two other ceiling panels, except that the number of heads is different in all three images, indicating that the dragon does not have multiple heads, but one and that its head is moving. The dragon’s head would not appear (to a viewer) to move in electric light (e.g., a cold light panel), but under firelight conditions of the time-period, the dragon would seem to strike like a viper; while the volcanos would explode and the horses run, the clouds racks race, and smoke and ash would billow. Mogao Cave 249 is ancient Chinese animated proto-cinema. Virtually the whole Dunhuang cave system is a vast complex of cinematic chambers.

We present engineering airflow to intercept the transmission of Covid19 in public spaces and public transportations, which relatively fast and simple. This technique is to suppress effectively and as massive as possible the spread of aerosols and droplets contaminated with the COVID-19 virus that is flying in the air by providing a vertical downward flow using fans placed on the ceilings and the use of floors of the certain material so that aerosol and microdroplets will not bounce back up, difficult to roll, and firmly attached to the floor. The numerical airflow simulation shows that positioning the fan on the ceiling of the room will cause the air particle to move faster downward, which will push the microdroplets to fall to the floor more quickly, so that the microdroplets and aerosols will quickly move away from the most risk organs from the transmission, namely the mouth and nose. The contactangle test results on several floor materials always show a value of fewer than 90 degrees. These phenomena cause microdroplets or aerosols that fall to the floor will stick tightly and not easily roll. This phenomenon will cause the room to be more sterile from aerosols and microdroplets that may be contaminated with Covid19. The room will be healthier and safer. This technique can be a solution that is relatively inexpensive and simple to implement on a field scale and is very effective in reducing the radius of the spread of droplets or aerosols in closed spaces, both public spaces and public transportation, such as trains and city buses which are very susceptible to Covid19 transmission.

Este trabalho analisou a distribuição da frequência e da participação na renda domiciliar de quatro tributos diretos nos domicílios brasileiros: Imposto Predial e Territorial Urbano (IPTU), Imposto sobre a Propriedade de Veículos Automotores (IPVA), Imposto de Renda de Pessoa Física (IRPF) sobre rendimentos do trabalho e contribuição previdenciária por estratos de renda e geográfico com base nos dados das duas últimas pesquisas de orçamentos familiares (POFs) 2008-2009 e 2017-2018. O estudo constatou que o IRPF sobre rendimentos do trabalho foi progressivo em todos os estados de renda. O IPTU foi progressivo até os 9% mais ricos onde estabiliza sua participação na renda. O IPVA e a contribuição previdenciária foram regressivos devido ao crescimento recente da propriedade de veículos entre os mais pobres e ao limite máximo da contribuição previdenciária do Regime Geral de Previdência Social (RGPS) para rendas superiores ao teto previdenciário, respectivamente. Por fim, o estudo faz algumas propostas para reforma tributária de forma a tornar esses tributos mais progressivos.

In this paper I approach one of Smith's most discussed exceptions to the liberty principle. Numerous authors have treated the tension between Smith's endorsement of a ceiling on interest rates and his system of natural liberty. Almost all authors take Smith at face value. I argue that, given the religious underpinnings of usury policy and its firm standing in prevailing opinion, Smith wrote esoterically on the matter, in part to ensure that his works and his legacy would remain temperate, widely agreeable, and alive. One notable feature of Smith's esotericism is that as soon as he states his argument for the ceiling he subverts that argument by saying that under the regulatory ceiling lenders “universally prefer” “sober people” to “prodigals and projectors” and are able to discriminate accordingly, which leaves the discerning reader wondering why that wouldn't also be the case in the absence of any ceiling.

The growth of the micro-aerial vehicle (MAV) industry is outpacing our understanding of how MAVs behave in cluttered environments. Search and rescue and product delivery (two key MAV applications) ...

The issues of energy saving, as well as comfortable operation of buildings in modern construction practice are relevant. The experience of operation of the premises, located above the basement, shows that the most common problem is the cooling of the floor slab and, as a consequence, the presence of a cold floor. The article presents the results of calculations on the change of thermal properties of the ceiling above the basement in residential buildings. A variant of insulation of the ceiling with ultra-thin liquid insulation is proposed. The graphical analysis of the problem is carried. As a result of graphical analysis, it was revealed that the proposed method of insulation makes it possible to increase the floor temperature in the rooms of the ground floor in the residential buildings.

Gender has become a prominent issue in political science research. However, most research has focused on women in legislative roles, while only some discussed women in powerful executive positions,...

Urban living spaces with piloti structures are at high risk for deregulation of building protocols. Recent fire case investigation results have shown the path of the fire from the initial ignition point to the exterior material via combustible ceiling materials; thus, preventing the spread of the fire through the ceiling material is a priority. Accordingly, investigations were conducted on the ceiling materials used in piloti structures, and it was confirmed that SMC, aluminum, DMC, and gypsum board were the main components, with the SMC ceiling materials accounting for more than 70% of the composition. Cone calorimeter tests were performed on these ceiling materials, and the heat fluxes of SMC, aluminum, DMC, and gypsum board were determined to be 217.10, 15.07, 1.78, and 41.92 kW/m2, respectively.

This paper investigates the critical stable sectional area (CSSA) of downstream surge tank (DST) of hydropower plant with sloping ceiling tailrace tunnel (SCTT). Firstly, two types of nonlinear mathematical model of hydropower plant with SCTT during transient process are established. Then, the criterion of operation stability of hydropower plant is obtained based on nonlinear stability theory. Formulae for CSSAs of DST under two types of mathematical model are derived. Finally, the similarities, differences, and relationships of different CSSAs are clarified. The effect mechanisms of the assumption of steady power output of hydro‐turbine and the SCTT on CSSA of DST are revealed. The recommended use conditions of different CSSAs are explained. The results indicate that, under the assumption of steady power output of hydro‐turbine, the formula for CSSA of DST of hydropower plant with SCTT is analytical and has a simple expression. Under the complete model, the formula for CSSA of DST of hydropower plant with SCTT is not analytical and has a complicated expression. The former formula is suggested to be given the priority of use because of good precision and concise expression. SCTT can improve the stability of hydropower plant and decrease the CSSA of DST.

The glass ceiling is a well-recognized phenomenon in the corporate sector thwarting aspirant women to gain senior management positions. It is an indiscernible barrier and a strong ceiling blocking women moving up in the management hierarchy. This paper, however, explores the existence of the second glass ceiling for women entrepreneurs who escaped the corporate world to start their businesses but are trapped by another glass ceiling. This research mainly explores the existence of a second glass ceiling for women entrepreneurs and the ways they used to get through it. This study is conducted for an in-depth understanding and uses the phenomenological approach. Semi-structured in-depth interviews were conducted with women entrepreneurs of Lahore. This paper apart from explaining the second glass ceiling also finds solutions to break it.