Small Room Research Articles

Urinary profiles of methoxyphenamine and its metabolite after inhalation of methoxyphenamine smoke in humans: aiming to distinguish between active and passive exposure

PurposeMethamphetamine (METH) is commonly abused through smoking. However, the lack of evidence regarding differences in urinary METH excretion after its active and passive inhalation has resulted in complications where the accused claims passive exposure. This study aimed to determine the differences in urinary excretion after active and passive inhalation of the drug, using methoxyphenamine (MPA) as a model for METH.MethodsBody temperature and locomotor activity were measured in mice as indicators of central nervous system toxicity. Six healthy adult male subjects were exposed to passive or active inhalation of MPA smoke in a small room, and urine samples were taken. MPA concentrations were measured using liquid chromatography–tandem mass spectrometry (LC–MS/MS).ResultsThere were no signs of toxicity in mice exposed to MPA smoke, ensuring the safety of the clinical study. Urinary MPA concentrations were significantly lower with passive inhalation compared with those of active inhalation. The maximum urinary MPA concentration in passive inhalation was 13.4 ng/mL, which was 1/60 of active inhalation with 800 ng/mL. The urinary excretion in passive inhalation until 24 h was 8.21 μg, which was 1/76 of active inhalation with 625 μg.ConclusionsSince METH and MPA are expected to be excreted similarly, urinary METH concentrations in passively exposed persons are expected to be lower than the cutoff value of the screening kit. If the urine screening test is positive, the suspect should be considered a METH user.Trial registration number: jRCTs031210604, registration date: Feb. 9, 2022.

Termoizolacioni premaz korišćenjem prirodnog kamena u prahu i epoksidnog kompozita za smanjenje sobne temperature

The ability of a roof to absorb heat is crucial for maintaining temperature stability within a room. Therefore, natural material composite coatings utilization offers a viable option for modern roof development. This research investigates how using natural stone mixed with epoxy, and applied as a coating on a galvalume surface, influences thermal conductivity and reduces room temperature. Temperature measurements were collected around a small room with a composite-coated roof, utilizing different types of rock in the composition. Thermocouples were placed 20 cm above the roof's surface, attached to the roofing composite, positioned beneath the galvalume layer, and within the small room. The results demonstrate a reduction in thermal conductivity and room temperature when natural stone powder is added to the roof. Experiments using composite coatings with various stone types exhibit varying degrees of room temperature reduction. Consequently, this research concludes that the unique properties of natural stone can effectively lower the thermal conductivity of roofs and decrease room temperature.

Enhancing displacement ventilation performance: Proposal of a new portable air purifying displacement ventilation unit

Displacement Ventilation (DV) has been known as an energy saving system as it relies on buoyancy force to draw hot air upwards to be displaced by cool air. The main strength of DV that recommends it nowadays is that a well-designed DV system prevents mixing of contaminants as they are dragged along the hot air upward flow leaving the occupied zone, breathing zone in particular, clean. However, the system’s effectiveness is lowered in large rooms due to design problem such as difficult balance between sufficient supply flow volume and low inlet velocity, furniture arrangement acting as obstacles, or room geometry. Hence, DV feasibility is limited to small and mid-size rooms. In order to expand the DV potential and applicability to all space types and sizes, this study proposes a portable DV air purifying unit. The unit is designed to be mobile consisting of air recycling unit with no duct connections which widens the range of use to cover a variety of indoor spaces as well as small to medium sized room. The unit has two main functions, one is reinforcing the temperature gradient as stratification crucial for DV, and the second is purifying recycled air. To investigate the effectiveness and feasibility of the proposed DV unit, block model calculations and CFD analysis were conducted. In a basic office room, multiple cases were calculated and assessed in terms of temperature distribution and stratification height. In addition, exhaled contaminants were simulated and the contaminant concentration was used as an indicator for the air quality. Observations on the proposed unit’s performance and design aspects were highlighted.

Challenges with Online Teaching and Learning of English Vocabulary

This article aims to examine the challenges facing secondary school teachers and students in English vocabulary online classes in Amman, Jordan. It also aims to propose the most effective ways to overcome the encountered challenges. To this end, qualitative semi-structured interviews were conducted with thirty teachers and twenty students to understand their experiences related to the online learningteaching process. Based on these interviews, several challenges that might obstruct this process were identified, with some of the challenges reported by teachers being similar to those reported by students. Teaching and learning challenges included poor class management, poor Internet connection, and large class sizes. Moreover, the findings of this study highlighted that one of the most important challenges that teachers encountered in teaching English vocabulary online was the impossibility of using realia. The study concludes with some solutions from both teachers and students to overcome these difficulties, such as using more advanced online platforms, e.g., Google Meet, World Word, and Microsoft Teams, as well as splitting students into small online rooms, and using games/plays.

The preliminary evaluation of design guidelines of stratum ventilation in a large tropical lecture hall

This article presents a study conducted to test the design guidelines of stratum ventilation (SV) for the conditions set in the tropics (Malaysia). Three different ventilation strategies and six different cases for SV were designed and examined by varying the layout of the return outlets and the air change per hour values. The ventilation strategy with a return outlet at the same level on opposite wall was found better than others. The simulation results of the medium-size room show that the thermal comfort is only favourable up to the centre region. Locations near the diffusers were noticed too cold and locations far away were too warm. In addition, the air flow pattern shows that the room has a high PPD due to quasi-stagnant zones that exist between the air jets from the diffusers. A similar condition does not exist in the small-size room, which was found under the acceptable range of PPD index (0%–25%). The ventilation strategy-1 (VS-1) is found with a greater energy saving with EUC 1.45 for the small room and 1.50 for the medium room compared to the other two ventilation strategies. The SV design guidelines are found adequate for the need of thermal comfort.

Novel perspectives for multi-actor collaboration in strategic environmental assessment using ST4S

The literature on strategic environmental assessment (SEA) reveals a growing number of scholars suggesting that SEA faces challenges, notably in terms of its capacity to support collaborative processes. One possible reason for this to happen relates to practice being saturated with standardized procedures that proffered SEA as a ‘night watchman’ on conventional impact-based conceptions. Such conceptions are mostly technocratic, leaving limited space for research-practitioners collaboration, and also small room for change provided they are legally well established. This article aims to show that adopting a more strategic thinking approach in conceptualizing and practicing SEA may increase opportunities for collaborative governance. Strategic thinking for sustainability (ST4S) is an innovative approach that can be used with SEA but also with other policy-making and planning assessment contexts and processes. It is strongly supported upon principles of governance, revealing a great capacity to promote multi-actor collaboration across institutional and disciplinary boundaries. We ground our research in the cross-fields of power, institutional and relational perspectives. We consider a multi-actor perspective to understand the potential of ST4S to promote relationships between different actors in a decision process and understand their institutional logics within processes of development. We also consider the notion of boundary spanning within ST4S to understand how collaborative practices (and potentials) can aim for cross-boundary work. We illustrate our analysis with concrete cases that used an ST4S approach (a SEA in Portugal and Peru, and a sustainability strategy in Portugal) to reflect on the challenging ‘relational turn’ needed for lasting collaborative practices.

다목적 홀의 음향 최적화를 위한 개발 잔향가변장치의 흡음특성 평가

The optimal reverberation time in a multi-purpose hall varies depending on the intended use (lecture, performance, etc.) and the type of performance (classical, musical, Korean traditional music, theater, etc.). In this study, devices for adjustable reverberation time (RT) were proposed. Sound absorption coefficients of four developed prototype devices in absorption and reflection modes were measured in the reverberation room according to the KS F 2805 and ISO 354. Additionally, to verify the variation range of RT developed device with the best reflection coefficient was installed in a small music practice room, and the variable range of RT was predicted and reviewed using a simulation tool. The results show that the sound absorption coefficient of device module-3 in absorption and reflection modes were 0.94 and 0.17 at 250 Hz, and 0.85 and 0.13 at 500 Hz, respectively. Additionally, the predicted results of the variable RT range between the two modes in an existing music practice room were 0.58 and 0.56 sec, at 250 and 500 Hz in octave band, respectively. An application of this is using developed devices in a multi-purpose hall for optimal reverberation environment.

High potential of small-room acoustic modeling with 3D time-domain finite element method

Applicability of wave-based acoustics simulation methods in the time domain has increased markedly for performing room-acoustics simulation. They can incorporate sound absorber effects appropriately with a local-reaction frequency-dependent impedance boundary condition and an extended-reaction model. However, their accuracy, efficiency and practicality against a standard frequency-domain solver in 3D room acoustics simulation are still not known well. This paper describes a performance examination of a recently developed time-domain FEM (TD-FEM) for small-room acoustics simulation. This report first describes the significantly higher efficiency of TD-FEM against a frequency-domain FEM (FD-FEM) via acoustics simulation in a small cubic room and a small meeting room, including two porous-type sound absorbers and a resonant-type sound absorber. Those sound absorbers are modeled with local-reaction frequency-dependent impedance boundary conditions and an extended-reaction model. Then, the practicality of time-domain FEM is demonstrated further by simulating the room impulse response of the meeting room under various sound absorber configurations, including the frequency component up to 6 kHz. Results demonstrated the high potential and computational benefit of time-domain FEM as a 3D small room acoustics prediction tool.

Analysis of the Influence of the Vertical Coaxiality of the Pillars on the Stability of the Resistance Structures, from the Ocnele Mari Saline

Abstract The Ocnele Mari rock salt deposit is exploited with small rooms and square pillars, on the horizons +226 m and 210 m. Following the exploitation of the lower horizon +210 m, the floor between the two horizons suffered instability phenomena, marked by fractures and cracks and local degradation of the pillars.Since the pillars at the two horizons have certain deviations from the coaxiality, the question was raised whether the instability phenomena were generated by the deviations from the coaxiality.This article presents the stability analysis of bearing structures, taking into account the actual geometry of pillars, 3D finite element analysis and analysis of safety factors at the ceiling level, calculated from 2D finite element models. The final conclusion is that the instability phenomena that occurred at the Ocnele Mari Saline were generated by the state of stresses and strains, produced by the spatial distribution of the underground voids and the geomechanical characteristics of the rock salt and insignificantly, by the deviation from the coaxiality of the pillars.

The Beethoven Syndrome: Hearing Music as Autobiography, by Mark Evan Bonds

<i>The Beethoven Syndrome: Hearing Music as Autobiography</i>, by Mark Evan Bonds

Review: Philip II of Spain and the Architecture of Empire

Review: <i>Philip II of Spain and the Architecture of Empire</i>

Dynamic daylight performance oriented design optimizations for contemporary reading room represented deep open-plan spaces

Appropriate daylight environments are essential for library reading spaces that commonly meet long-term reading and writing. While conventional window form, position, and orientation designs felt increasingly difficult to comply the transformation towards deep, multi-functional open-plan modes of contemporary reading spaces. Insights of key design variable optimizations that can effectively enhance the dynamical daylight performance of open reading room represented deep open plans, therefore, become urgently needed. Employing dynamic daylight simulations validated by scaled-model measurements, this study firstly screened out the key design variables affecting both perimeter and deep areas through coupled orthogonal test-based sensitivity analyses. Afterwards, through daylight simulations considering differentiated illumination thresholds of both areas, single-factor analyses evaluating impacts of key design variables (window height and width coefficients, room heights, transmittances, and orientations) over both daylight intensities and glare probabilities have been thoroughly carried out. Qualified depths of both lighting threshold had been examined. The window width coefficient and transmittance were validated as critical design variables for perimeter area glare control. Window height and width coefficients, as well as room height were confirmed as main impacting factors to ensure mid-deep and deep zone illuminations, respectively. Moderately large window height (0.7∼0.8) and width (around 0.7) coefficients, glass transmittance (around 0.7) while moderately small room height (3.3∼3.6 m) are recommended. The research outcomes can assist in more effective decision-makings of early design phase daylight optimizations for common deep open-plan spaces. • Dynamical daylight simulations for varied depths among deep open-plans performed. • Orthogonal test based sensitivity analyses and single-factor analyses conducted. • Key variables for perimeter area glares and deep zone illumination levels validated. • Suitable design strategies of key variables for balanced daylight quality proposed.

Breakout Rooms Serve as a Suitable Tool for Interprofessional Pre-Service Online Training among Students within Health, Social, and Education Study Programs

Higher education institutions must prepare students from health, social, and teacher education programs for interprofessional collaboration (IPC) among children and young people with challenging childhood experiences. We wanted to explore if digital small group rooms, breakout rooms, are feasible for students to learn about, from, and with each other in an interprofessional learning (IPL) initiative, in order to practice IPC. This study is a repeated cross-sectional study from the academic years 2020/21 and 2021/22 with 5412 students. The students worked in student-led IPL groups with a case-based learning approach and limited interaction with supervisors. The youngest students agreed to a larger extent that they learned more about, from, and with other students. The teacher students were more positive towards discussing sensitive issues in breakout rooms than the health students. The health students agreed to a larger extent than the teacher students that breakout rooms were suited for pre-service IPC training. The results from this study indicate that breakout rooms provide a potential arena to practice generic skills. If properly organized and structured, breakout rooms can be an excellent learning resource. Breakout rooms provide a safe online environment for learning and practicing IPC, and for training on talking about sensitive issues.

Experimental study on the effect of fire alarms on occupants for situational awareness and evacuation decision‐making using a mobile virtual reality head‐mounted display

AbstractFire alarms play a significantrole in situational awareness and decision‐making pertaining to evacuation for fire evacuation safety in office buildings that include small rooms, where many occupants cannot directly see fire or smoke. We conducted experiments using a mobile VR head‐mounted display to examine how individuals perceive the sound of fire alarms in rooms of different sizes. Comparing the cases of hearing the alarm sound in the large room and the small room, approximately 70% of the test participants answered that they wanted to check the situation more when they were in the small room because they could not understand the surrounding situation. Regardless of the room size, when test participants hear the early warning voice, approximately 40% of them would check the neighborhood and evacuate, and when they hear the evacuation directive voice alarm, more than 90% will take the same action. We also discussed the awareness process of occupants considering this result and the configuration of a smoke detection system in Japan. Approximately half of the people in the large room take checking actions; however, the remaining people do not take specific confirmation actions for about 1–3 min and do not check for fires or evacuate.

Preparation and characterization of phase change material microcapsules with modified halloysite nanotube for controlling temperature in the building

Microencapsulated phase change material (mPCM) with effective heat transfer and flame retardant is highly desirable given today’s increasing energy demand. In this article, the halloysite nanotube (D-HNT) was modified by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and then inserted into the mPCM (D-H-mPCM) successfully. The transmission electron microscope, X-ray photoelectron spectroscopy and FT-IR results showed that the DOPO is grafted in both interior and exterior walls of halloysite nanotube (HNT), and the D-HNT is successfully inserted into mPCM. According to thermogravimetric analysis tests, D-H-mPCM was the best thermally stable sample among other mPCM for the existence of HNT and DOPO. The differential scanning calorimetry tests showed that the latent heat of D-H-mPCM was 113.52 J/g, and the D-HNT embedded in the mPCM greatly contributes to the heat transfer of the PMMA shell. To detect the flame retardancy and temperature control performance of mPCM samples, D-H-mPCM was incorporated into epoxy resin (EP-D-H-mPCM). The data of the cone calorimeter test suggested the EP-D-H-mPCM exhibited the lowest peak of heat release rate (pHRR) and total heat release (THR) of 572.65 kW/m2 and 93.95 MJ/m2 respectively. Finally, the small room model test and infrared thermal imager test showed the application of D-H-mPCM in EP can regulate indoor temperature and moderate temperature fluctuation. This work provides a new methodology to improve both thermal conductivity and flame retardancy of mPCM.

Finding the best hardware configuration for 2D SLAM in indoor environments via simulation based on Google Cartographer

One of the most challenging topics in robotics is simultaneous localization and mapping (SLAM) in the indoor environments. Due to the fact that Global Navigation Satellite Systems cannot be successfully used in such environments, different data sources are used for this purpose, among others light detection and ranging (LiDARs ), which have advanced from numerous other technologies. Other embedded sensors can be used along with LiDARs to improve SLAM accuracy, e.g. the ones available in the Inertial Measurement Units and wheel odometry sensors. Evaluation of different SLAM algorithms and possible hardware configurations in real environments is time consuming and expensive. In our study, we evaluate the accuracy of mapping and localization (based on Absolute Trajectory Error and Relative Pose Error). Our use case is a robot used for room decontamination. The results for a small room show that for our robot the best hardware configuration consists of three LiDARs 2D, IMU and wheel odometry sensors. On the other hand, for long hallways, a configuration with one LiDAR 3D sensor and IMU works better and more stable. We also described a general approach together with tools and procedures that can be used to find the best sensor setup in simulation.

Wave acoustic solutions in small rooms

This presentation will discuss the growing application of wave based solutions due to the increased processing power of desktop and distributed cloud cluster computing. The causes and mitigation of four types of potential acoustical distortion in small rooms, below and above 200 Hz, will be presented. Below 200 Hz, approaches to minimize modal effects and the speaker boundary interference response will be presented. We will discuss limitations of traditional dimensional ratio determinations, more accurate wave-based predictions, importance of speaker and listener locations, and prediction and measurement of low frequency absorption devices. Above 200 Hz, comb filtering from strong specular reflections and poor diffusion are potential problems. We will describe the necessary ratio of surface width to incident wavelength for a specular reflection and its effect on comb filtering. Finally, we describe the importance of creating a mixing room design and the use of broad bandwidth diffusive surfaces, which can be both measured and simulated with a virtual goniometer boundary element program called VIRGO, from a 3D CAD file topology of any shape. This offers the acoustician the ability to evaluate surface topologies that are of interest in a room design quickly and inexpensively.

Recording studio sound isolation: A case study of challenges faced in measuring door transmission class (DTC) and noise isolation class (NIC) in small rooms

This case study examines the challenges faced in measuring the DTC and NIC between a recording studio control room and the studio recording space. Challenges included structural radiation around the tested partition, flanking paths, ADA ramp design, and improper use of the space during construction. The measurements were performed following the procedures of ASTM E2964-14 Standard Test Method for Measurement of the Normalized Insertion Loss of Doors and ASTM E336-19 Standard Test Method for Measurement of Airborne Sound Attenuation between Rooms in Budlings. The spaces were designed by an acoustical consultant and desired by the owner to have extremely high levels of sound isolation. Furthermore, the nature of the intended clientele necessitated high performance, a high finish level, and state of the art technology. The investigators were not part of the design team and were invited to measure the space to document and validate the final performance. This presentation will outline the findings, challenges in measurement, and the steps taken to increase the sound isolation performance.

The evolution of Blackbird Studio C

Starting in 2002 John and Martina McBride set out to create several small rooms, each one unique in design and technology. George Massenburg (GM) was asked to coordinate the design of one of the rooms and given the mandate to make it the most advanced room imaginable. GM specified that the room should offer an accurate monitoring environment for more than one listener, a reasonable presentation of how materials will sound in multiple circumstances outside of the space, a flexible environment that doesn’t compromise musical and artistic contexts, an accurate representation of virtual sources (sources spread across one or more loudspeakers) to more than one listener, a room with linear, supportive ambience, which as much as possible, has near-equal decay rates across as much of the frequency spectrum as possible. In June 2004, GM contacted Peter D’Antonio with a proposal to collaborate on a new surround music monitoring/control/recording room, which became Studio C. The resulting diffusor design covering all four walls and ceiling, with corner bass absorption, will be presented. Since opening the room has been used successfully and has recently installed a Dolby Atmos system. The presentation will also present user perceptions from 2005 to the present.

Evaluating the reverberation chamber as a small room: How room dimensions affect the generalization of testing results

Testing acoustic properties is performed in specially designed reverberation chambers according to relevant ASTM, ISO, and other international standards. Performing this testing is complicated by the fact that practical considerations limit the size of the reverberation rooms. Where the dimensions of the room are similar in size to the wavelength of the frequency of interest, modal behavior becomes dominant, and the statistical analysis of room acoustics based on the diffuse sound field theory is not sufficient to characterize the sound field. However, standard methods implement formulas which assume a diffuse sound field to compare results from different labs. Using the Maxon Acoustics Lab, a purpose-built floor ceiling test lab comprised of two stacked, 300 m3 reverberation chambers, we will examine the various physical criteria for evaluating a theoretically diffuse sound field. Discussion will include historical debates concerning the validity of comparing measurements in different labs and an analysis of the Maxxon Lab through the lens of various methods for evaluating the acoustic environment in comparison to the statistical analysis for room acoustics. Methods will include analysis of modal density and distribution, sampling of the sound field per ASTM standards E90, E492, and C423, the Schroeder frequency, and other statistical analyses.