Steel Pan Research Articles

Anisotropic Specular Image‐Based Lighting Based on BRDF Major Axis Sampling

AbstractAnisotropic specular appearances are ubiquitous in the environment: brushed stainless steel pans, kettles, elevator walls, fur, or scratched plastics. Real‐time rendering of these materials with image‐based lighting is challenging due to the complex shape of the bidirectional reflectance distribution function (BRDF). We propose an anisotropic specular image‐based lighting method that can serve as a drop‐in replacement for the standard bent normal technique [Rev11]. Our method yields more realistic results with a 50% increase in computation time of the previous technique, using the same high dynamic range (HDR) preintegrated environment image. We use several environment samples positioned along the major axis of the specular microfacet BRDF. We derive an analytic formula to determine the two closest and two farthest points from the reflected direction on an approximation of the BRDF confidence region boundary. The two farthest points define the BRDF major axis, while the two closest points are used to approximate the BRDF width. The environment level of detail is derived from the BRDF width and the distance between the samples. We extensively compare our method with the bent normal technique and the ground truth using the GGX specular BRDF.

Reply to the comments on "Coffee bean sign, steel pan sign and whirl sign in sigmoid volvulus".

We thank Prof. Atamanalp and colleagues for their interest and valuable comments on our article. The authors have highlighted important considerations in the diagnosis of sigmoid volvulus (SV). We would like to respond to their comments. Firstly, although we agree with their opinion that CT, MRI, and endoscopy are more reliable diagnostic tools than plain radiography, we still emphasize that diagnostic imaging for SV is initially based on plain radiography, as recommended by the WSES consensus guidelines. Since SV is the third most common cause of colonic obstruction worldwide, the accessibility of plain radiography is crucial. Among the many plain radiographic signs of SV, Levsky et al. reported that the most sensitive signs were absence of rectal gas, followed by inverted-U appearance and coffee bean sign. Understanding these signs may lead to early detection of SV and further CT evaluation for ischemia or perforation. Despite the high value of plain radiography, there is a global tend to use CT instead from the outset. Secondly, we agree with their opinion that endoscopy is not only a therapeutic, but also a diagnostic procedure to assess mucosal viability. In addition, we believe that endoscopy is also useful in ruling out other obstructive lesions, including colorectal neoplasia and complicated sigmoid diverticular disease. In the clinical setting, endoscopy is performed after the diagnosis of SV by plain radiography or CT and serves as the first line of decompression of SV when ischemia or perforation is not suspected. Finally, we congratulate Prof. Atamanalp and colleagues for their dedicated contribution to the large-scale SV studies in Eastern Anatolia, Turkey, where SV is endemic.

Ammonia and greenhouse gas emissions from beef feedlot surface material treated with aluminum sulfate (alum) or microbial amendments.

A lab-scale study evaluated ammonia (NH3 ) and greenhouse gases, emissions when aluminum sulfate (alum) or a microbial product were added to beef feedlot surface material (FSM). Three kilograms of FSM and 1.5kg of water were added to stainless steel pans (50cm × 30cm × 6.5cm). Treatments included a control (no amendment), 450g alum, or 0.5g microbial product. The pans were placed in an environmental chamber that was maintained at 23°C and 50%-60% humidity. Emissions were measured three times weekly for 3 weeks. Ammonia, N2 O, and CH4 were lower (p<0.01) from pans with amendments compared to the control pans; emissions from the FSM that received the microbial treatment were lower than the FSM treated with alum. Methane emissions were similar for the control and alum-treated FSM but lower (p<0.01) for the FSM that was treated with the microbial product. Nitrate-N was lower, and NH4+ -N and total sulfur concentrations were higher in FSM treated with alum compared to no treatment or the microbial treatment (p<0.01). Results indicate that both alum and microbial amendments have benefits in reducing emissions from the feedlot surface, with the microbial product providing additional reductions in emissions compared to the alum.

Experiments on the Application of Class A and B Fires to Derive the Optimum Air Ratio of Compressed Air Foam Systems

This experiment was designed to increase the utilization of fire engines equipped with compressed air foam systems (CAFS) at the scene of a fire. The purpose of this experiment was to determine the optimum air ratio for the CAFS. Wood crib fires (class A) and steel pan fires (class B) were both extinguished using synthetic surfactant CAFS installed in a fire engine. According to the temperature drop rate (°C/s), the optimum air ratio was thirteen and five in the class A and B fires, respectively. The results derived from this experiment can be used to strengthen fire scene response capabilities.

Jump Up! Caribbean Carnival Music in New York

Jump Up! Caribbean Carnival Music in New York

Analysis of conjugate Marangoni natural convection in a heating system with an open boundary flow

Marangoni natural convection involved in a heating system with an open boundary layer flow has been numerically analyzed in this article. An isoflux heater is placed below a steel pan (material: AISI 4340 steel) which is partially/fully filled with water to make this model more realistic. The surrounding of this pan has a two-dimensional air domain including a water-air interface. Hence, the air domain has three open boundaries within the computational domain. Conjugate natural convection heat transfer takes place from the solid pan to water and then air, whereas Marangoni convection is facilitated at the water-air interface. Two-dimensional, unsteady Navier-Stokes and energy equations are considered as the governing equations, and those are solved with the help of finite element method. Rayleigh number is varied in the range of laminar regime from 6 × 104 to 3 × 107 as the governing parameter under different water level conditions. Thermal and flow fields are visualized qualitatively, whereas quantitative distributions of average Nusselt numbers are taken for further analysis. Finally, the exergy of the system is inspected in terms of total entropy generation at individual flow domains. Here, overall heat transfer performance shows a strong dependency on the change of Rayleigh number.

Experimental Research on the Effectiveness of Different Types of Foam of Extinguishing Methanol / Diesel Pool Fires

ABSTRACT Storage tank fire can pose great threats to life and environment as it can cause strong radiant heat, fast-spreading flame, and destructive explosion. In this research, a 1.5 m-diameter circular steel pan is used to simulate the full surface fire of a storage tank in an industrial park. A self-built fire-extinguishing system gently releasing foam at the rate of 11.4 L/min was applied for the evaluation of the effectiveness of different types of foam of extinguishing diesel/methanol pool fires. Experiments were conducted to analyze the temperature increases of fires after releasing different types of foam. In this research, the nondimensional average temperature 0.85 and 0.71 regard as the fire extinguishing temperatures of methanol and diesel fuel, respectively. Over the spreading process, the increase in foam spreading length over time still follows the power law. The fastest flow velocity of 6% FP/AR in methanol pool fire and 6% Synthetic foams in diesel pool fire was 0.0136 m s −1and 0.044 m s −1, respectively, with a foam application rate of 11.4 L/min. The results show that, in the methanol pool fire, the cooling effect of the foam is ranked as FP/AR > AFFF > AFFF/AR > S > FP > S/AR. And the cooling effect of foam for diesel is ranked as S > S/AR > AFFF > AFFF/AR > FP > FP/AR. Foam’s cooling impact is especially notable in diesel pool fires. As for methanol pool fires, the foam extinguishing mechanism is mainly based on the “anti-soluble film” effect, which quickly forms a covering layer on the surface of the flammable liquid, seperating the flame from heat feedback and inhibiting the generation of flammable vapors, insulating itself against the air and ultimately asphyxiating the fire.

Hybrid Effect of Steel Bars and PAN Textile Reinforcement on Ductility of One-Way Slab Subjected to Bending.

Textile reinforced concrete (TRC) has gained attention from the construction industry due to several characteristics such as its lightweight, high tensile strength, design flexibility, corrosion resistance and remarkably long service life. Some structural applications that utilize TRC components include precast panels, structural repairs, waterproofing elements and façades. TRC is produced by incorporating textile fabrics into thin cementitious concrete panels. However, in order to use this strengthening method in construction practice, a design model is required. Investigating the combined effect of conventional steel and textile reinforcement on the ductility behavior of composite TRC/RC one-way slab is vitally important. Therefore, the current study describes the proper methods of calculating the ductility of the composite concrete reinforced by a direct combination of conventional steel and textile reinforcement. Four methods are presented to calculate the ductility of the three considered one-way slab specimens. The three slabs having dimensions 1500 mm × 500 mm × 50 mm were reinforced by steel bars (SRC), by steel with one layer of carbon fabric (SRC + 1T), and by steel with two layers of carbon fabric (SRC + 2T). The three slab specimens were cast by the hand lay-up method, removed from the molds, cured, and then tested in flexure after 28 days using the four-point bending method. The obtained results and calculations revealed the non-reasonability of using the conventional method based on yielding of steel reinforcement as the only criterion in the ductility determination. The results also confirmed the suitability of using the energy-based method over other discussed methods in the calculation of the ductility for the hybrid reinforced members.

Manufacture and characterization of carbonated lightweight aggregates from waste paper fly ash

The combustion of biomass and waste paper sludge in a fluidized bed is ecologically profitable. However, a large amount of by-product with high hydraulic reactivity is produced and is considered as wastes. Most of the time the waste paper fly ash (WPFA) goes to landfills, therefore new utilization methods are necessary. In some countries, the high content of metallic and metalloids trace elements (MMTE) in WPFA, more specifically Barium (Ba) and Lead (Pb) makes its valorization difficult. In this paper, the Lightweight Aggregates (LWA) was produced from WPFA by granulating with water in high-intensity granulator. Since WPFA is rich in CaO, the addition of water promotes rapid setting and hydration compared to other types of ash. In this study, different granulation parameters were investigated, such as the rotation modes between the steel pan and the impeller, the rotation speed of the steel pan, the granulation time, in order to improve the mass percentage of the targeted LWA (2–16 mm). In order to evolve the immobilization potential of Ba and Pb, a carbonation process was performed, exposing the manufactured LWA to pure carbon dioxide (CO2) gas at laboratory scale. The physical, morphological, thermal and mechanical characterizations were performed on LWA for use in mortars, concretes or civil engineering constructions.Results have demonstrated the influence of the rotation mode between the steel pan and the on the distribution of WPFA inside the steel pan and the change in the growth rate of the granules can be observed. Increased density and improved compressive strength with low porosity and water absorption were also found in LWA after carbonation. This was due to the occurrence of both a carbonation reaction and a hydration reaction. Furthermore, the results of thermogravimetry and SEM-EDS confirmed the formation of hydrated phases (ettringite, carboaluminates), also the formation of calcite in the pores and the external surface of the LWA. Regarding environmental aspects, the results have revealed that Ba and Pb were well immobilized in the solid matrix after carbonation.

Sweet Tassa: Music of the Indian Caribbean Diaspora

Sweet Tassa: Music of the Indian Caribbean Diaspora details the history, repertoire, and socio-political significance of tassa drumming in Trinidad &amp; Tobago. The film profiles the life and work of noted tassa drummer Lenny Kumar and his family while also developing the notion of tassa performance practice as a metaphor for Indian Trinidadian cultural and national identity. In the process, the film traces tassa’s movement from India to the Caribbean, summarizes its transformation in diaspora, and speculates about its future.&#x0D; Proceeding from analysis of tassa repertoire in Muslim and Hindu performance contexts, the film explores tassa’s physical and conceptual transformations in diaspora and the ongoing push to make tassa a co-national instrument alongside steel pan. In this regard, interviewees discuss the implication of tassa as “foreign”—despite more than 150 years of Indian presence in the Caribbean—and therefore unsuitable as a co-national instrument alongside steel pan. The film’s conclusion emphasizes tassa as an encapsulation of Indian identity: tassa’s performance contexts and performance practice signal India as a place of origin. Yet these very same aspects, by virtue of their persistence in diaspora, equally signal Trinidad and Tobago as home.

Coffee bean sign, steel pan sign and whirl sign in sigmoid volvulus.

A 66-year-old man presented with abdominal distension. A plain radiograph showed the coffee bean sign, suggesting sigmoid volvulus (SV). The CT scans disclosed the steel pan sign, the whirl sign, and the beak-shaped transition point, confirming SV. He improved with colonoscopic decompression and detorsion. Characteristic radiographic signs of SV are briefly discussed.

Meaningful Collaborations: An Introduction to Music of Jamaica

The purpose of this column is to explore a meaningful collaboration between a classroom music teacher and an expert from a music culture. Dr. David Aarons from Jamaica worked with a music educator and a class of 5th grade students. They explored dance traditions, steel pan performance, singing games, and stories. They also discussed sociocultural and sociohistorical meanings of the lyrics, instruments, and hybrid nature of many of the current traditions.

Experimental and numerical study on the evaporation rates of liquid fuels using a controlled atmosphere cone calorimeter

The work described in this paper presents a set of experimental tests carried out in a Controlled Atmosphere Cone Calorimeter (CACC) in order to study the evaporation rate of a 250 ml-‘batch’ of n-heptane and methanol poured into an insulated 0.10 × 0.10 × 0.04 m3 steel pan and exposed to two ‘nominal’ irradiation levels of 25 and 50 kW/m2. A low oxygen concentration is imposed during the CACC tests. The intent is to provide experimental data for the assessment and validation of the numerical modelling of liquid heat-up and evaporation in pool fires, without the need to model combustion and the subsequent associated complex phenomena. The analysis of the mass loss rate profiles shows that the evaporation rate of n-heptane increases with time due to the preheating of the liquid, whereas for methanol, a quasi-steady-state is reached. This is due to differences in specific heat, boiling point and latent heat of vaporization. Numerical simulations of the liquid phase using the Fire Dynamics Simulator (version 6.7.0) point out the importance to account for increased heat transfer due to the convective motion of the liquid by increasing the thermal conductivity of the liquid by 10–20 times. Other limitations and uncertainties in the modeling are also highlighted.

Carnival, Calypso and Steel Pan: A Bibliographic Guide to Popular Music of the English-speaking Caribbean and its Diaspora by John Gray

Carnival, Calypso and Steel Pan: A Bibliographic Guide to Popular Music of the English-speaking Caribbean and its Diaspora by John Gray

Fatal poisoning by ingestion of a self-prepared oleander leaf infusion

An unusual case of poisoning by the ingestion of oleander leaves is reported. A 71 year old male laboratory technician committed suicide at home in this unusual manner. At the death scene a steel pan and other paraphernalia, used for the extraction of oleandrin and other cardiac glycosides from the leaves of the Nerium oleander plant were found.Toxicological investigations for oleandrin, oleandrigenin, neritaloside, and odoroside were performed by LC–MS/MS on all biological samples (peripheral blood, vitreous humor, urine, liver, gastric contents) and on the yellow infusion found at the death scene.In all samples, toxic levels of oleandrin were detected (blood 37.5 ng/mL, vitreous humor 12.6 ng/mL, urine 83.8 ng/mL, liver 205 ng/mg, gastric content 31.2 µg/mL, infusion 38.5 µg/mL). Qualitative results for oleandrigenin, neritaloside, and odoroside were obtained. Oleandrigenin was present in all tissue samples whereas neritaloside and odoroside were absent in the blood and vitreous humor but present in urine, liver, gastric content, and in the leaf brew.The purpose of this study was the identification of oleandrin and its congener oleandrigenin, detected in the vitreous humor. The blood/vitreous humor ratio was also calculated in order to assess of the likely time interval from ingestion to death. According to the toxicological results death was attributed to fatal arrhythmia due to oleander intoxication. The manner of death was classified as suicide through the ingestion of the infusion.

The Steel Pan and Decolonizing Mental Health

The Steel Pan and Decolonizing Mental Health

Mode studies on note sections of a Gubal

Over the years, Felix Rohner and Sabina Schärer, of Panart in Bern, Switzerland have implemented a number of significant modification to the standard Caribbean Steel Pan. These include using custom rolled sheet metal in place of commercially available used 55 Gallon drums, sinking the pan in a press rather than hand hammer sinking, dispensing with chiseled note section boundaries in favor of natural narrow change in curvature, adding central domes which give rise to more order in high overtone mode patterns, and building a lap held, hand played Hang. The latest addition to the Panart family is the Gubal, an inverted Hang with an added large dome on the bottom and the playing area, including the tone hole, at the top. Electronic Speckle Interferometric mode representations for Gubal note sections will be shown to illustrate spectral content of the Gubal.

Feasibility Study of Pressure Boiled Method on Defibrillation Stalk Sweet Sorghum Fibres Waste

Today, due to environmental reasons and limited of fossil resources take many researchers to develop new and renewable materials. Bio-composites which is consisted of synthetic polymers matrix and natural fibres, is one of the alternatives to reducing its problems. Among of natural fibre that has good potential to be used as reinforcement in synthetic polymer matrices is sorghum fibre. However the hydrophilic nature of natural fibers causes it to be incompatible with synthetic polymer matrices which have hydrophobic properties and it’s need to surface modified with particular treatment. The aim of this work was conducted to study the effect of hydrothermal treatment through pressure boiled method by using distilled water in a pressurized stainless steel pan cooking for 5 minutes to defibrillation and hydrophilic properties of stalk sweet sorghum fibres. Evaluation of the experiments was characterized with Field-Emission Scanning Electron microscope (FE-SEM), Fourier Transformation Infra-Red (FTIR) Spectroscopy and sessile drop test instruments, respectively. The experiment was found that using hydrothermal treatments through pressure boiled method led to a removal of binding materials, such as a wax, hemicellulose and lignin, and enhancement the hydrophilic properties of sorghum fibres.

No Fear, Just Fun!: Meaningful, Memorable Musicking in Secondary General Music

Secondary general music is hard to define. For some, this denotes an accelerated version of elementary general music or a decelerated version of a college music appreciation course. Others view this as any nontraditional ensemble geared for middle or high school students, such as guitar, keyboard, or steel pans. Still, for others, secondary general music is not so much a stand-alone course as it is any time devoted to teaching fundamental skills to students in band, orchestra, and choir so they may more successfully perform the repertoire. The authors acknowledge each of the above-listed views as valid; thus, rather than debate what is secondary general music, we will highlight each viewpoint in a three-part series. The first of this series will focus on a class structure where students experience various activities all while learning music fundamentals, studying music history, and developing music literacy skills.

Music competitions, public pedagogy and decolonisation in Trinidad and Tobago

ABSTRACTThis article examines music’s role in decolonising processes in Trinidad and Tobago, focusing on postcolonial national identity politics with reference to the country’s two largest ethnic groups: those descended from enslaved Africans and those from indentured labourers from India. First, the article traces the nationalisation of Creole culture – defined in terms of African-European syncretism – from the 1950s onwards, and it describes the state’s use of music competitions and educational programmes to institutionalise Carnival, calypso, and steel pan, all associated largely with African Trinidadian culture. This impacted on Indian Trinidadians by excluding them from inscriptions of national identity. The article concludes with a discussion of Indian Trinidadian cultural resurgence, tassa competitions, and the growth of public pedagogy from the 1970s that established tassa as an icon of Indianness; and all illustrating how music was used in a complex decolonisation process (relating to colonial rule and the Creole mainstream).