1,575 research outputs found

    An improved experimental method for local clothing ventilation measurement

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    A clothing local ventilation measuring device based on the Lotens-Havenith steady state tracer gas method was developed and an improved experimental method for understanding local ventilation mechanisms was proposed. The local ventilation system can measure the arm, chest and back ventilation rates at the same time. Local ventilation mechanisms of an impermeable garment at two activities (static, walking) and two wind speeds (no wind, 1.2m/s) were studied, with a focus on determining the pathways of ventilation through the different garment openings. The results showed that local ventilation rates of chest, back and arm varied considerably over locations and conditions. As expected, ventilation rates were highest for all locations at walking with wind conditions. Ventilation mechanism changed at different walking and wind conditions. The main air exchange pathway for all locations was through the garment bottom. Wind had a greater impact on clothing local ventilation than walking. Relevance to industry: Clothing ventilation impacts worker's thermal comfort and safety directly both in the cold and heat. The new clothing local ventilation measuring device developed in this paper can measure both clothing local and whole ventilation. It can also help us to separate the different pathways for heat loss through clothing.© 2013 Elsevier B.V

    Local ventilation and wear response of working jackets with different fabric permeability

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    Purpose – An experimental study was conducted to investigate the local ventilation (the right arm, the chest and the back) and wear response of three types of working jackets in different conditions. The relationship between the local ventilation and its related wear response was also explored. The paper aims to discuss these issues. Design/methodology/approach – A clothing local ventilation measuring system was developed based on the steady state method to measure the local ventilation of the right arm, the chest and the back. Separate wear trials were conducted to determine the local skin temperature, local microclimate temperature and humidity, clothing local surface temperature, heart rate (HR), eardrum temperature and subjective perceptions. Findings – The results indicated that the back part of the jacket had the highest ventilation, followed by the chest and the arm. Fabric permeability affected the local ventilation of the arm and the chest more than on the back. Clothing local surface temperature was significantly related to garment regions but not to fabric permeability. Back ventilation and back surface temperature, arm or chest ventilation and local microclimate humidity of the arm or chest, HR and back ventilation, local ventilation of the arm or the chest and its related thermal sensation, had significant linear relationships. Originality/value – The research will help to understand the relationship between the air exchange of the microclimate and the wear response, and thus gives some suggestions on garment design or selection, especially for the working garments

    A new experimental study of influence of fabric permeability, clothing sizes, openings and wind on regional ventilation rates

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    In this study, a local ventilation rates (VR) measuring system based on stead-state method was developed. This system can measure the local VR of the right arm, the left arm, the chest and the back locations of the upper body garment simultaneously. The whole clothing VR can also be computed. To study the influence of fabric permeability, clothing sizes, hem opening, and wind on local VR of the right arm, the chest and the back of the working garments, 9 jackets with different sizes and fabric permeability (permeable, semi-permeable and impermeable) were made. The results showed that the local VR for each garment location were significantly different. The chest had the largest local VR. Clothing ventilation rates were not liner with garment sizes. Closing garment bottom decreased more air exchange for chest and back comparatively. Wind increased both local and whole VR significantly. But the impacts were different according to different locations. © 2013 The Korean Fiber Society and Springer Science+Business Media Dordrecht

    Effects of wind and clothing apertures on local clothing ventilation rates and thermal insulation

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    The purpose of this study was to investigate the effects of wind (0, 1.1 m/s) and clothing apertures (not closed, closed hem, closed hem and neck) and the combined effects of them on local clothing ventilation rates and localized thermal insulation. Nine working jackets with identical design but different garment sizes and fabric permeability were made. The results showed that wind and clothing apertures had distinct effects both on the local ventilation rates and the local thermal insulation. The local ventilation rates of the right arm were largest at 1.1 m/s wind speed with the clothing hem closed. Chest and back ventilation rates were higher at wind than at no wind. Closing the garment hem affected the local thermal insulation of the impermeable garments mostly. In addition to wind and garment apertures, garment sizes and fabric permeability also impacted the local ventilation rates and the thermal insulation

    Penggunaan Metode Eksperimen Pada Pembelajaran Materi Sifat Bahan Dan Kegunaannya Terhadap Hasil Dan Respon Belajar Siswa Kelas IV Min Tungkob Aceh Besar

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    The research on the use of experimental methods in learning characteristics of material and its usefulness toward students\u27 achievements and learning responses of Level 4 primary school students of MIN Tungkob Aceh Besar aims to determine students\u27 learning outcomes and responses toward the use of the method. This study uses experimental research. The data collection techniques were using test and distributing questionnaire to the students. The samples in this experimental study were students of class IV3 totaling 34 people as the experimental class and the class IV4 totaling 31 people as the control class. The data, which is the students\u27 learning outcomes collected from pretest and posttest, were analyzed using t-test formula. The data from the students\u27 questionnaire responses were analyzed using percentage formula.The result was that the students\u27 learning outcomes from the experimental class and the control class showed significant differences. Students\u27 responses toward the use of experimental methods in learning material characteristics and its usefulness were also very positive, where the students are very excited and interested in learning to use the experimental method in the study of material characteristics and its usefulness

    sj-docx-1-mcr-10.1177_10775587231221852 – Supplemental material for Public Reporting and Consumer Demand in the Home Health Sector

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    Supplemental material, sj-docx-1-mcr-10.1177_10775587231221852 for Public Reporting and Consumer Demand in the Home Health Sector by Jun Li in Medical Care Research and Review</p

    Control of Hyperbranched Structure of Polycaprolactone/Poly(ethylene glycol) Polyurethane Block Copolymers by Glycerol and Their Hydrogels for Potential Cell Delivery

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    A series of biodegradable amphiphilic polyurethane block copolymers with hyperbranched structure were synthesized by copolymerizing poly­(Δ-caprolactone) (PCL) and poly­(ethylene glycol) (PEG) together with glycerol. The copolymers were characterized, and their composition and branch length were varied with the feeding ratio between PCL, PEG, and glycerol used. Hydrogels were formed from these copolymers by swelling of water at low polymer concentrations. The hydrogels were thixotropic, and their dynamic viscoelastic properties were dependent on the copolymer composition, branch length, and polymer concentration. Hydrolytic degradation of the hydrogels was evaluated by mass loss and changes in molecular structures. The porous morphology of the hydrogels provided good permeability for gas and nutrition. Together with the tunable rheological properties, the hydrogels were found to be suitable for 3D living cell encapsulation and delivery. The morphology of the solid copolymers was semicrystalline, while the hydrogels were totally amorphous without crystallinity, providing a mild aqueous environment for living cells. When the encapsulated cells were recovered from the hydrogels followed by subculture, they showed good cell viability and proliferation ability. The results indicate that the hyperbranched copolymers hydrogels developed in this work may be promising candidates for potential injectable cell delivery application

    Chiral Pentacarboxycyclopentadiene-Based Brþnsted Acid-Catalyzed Enantioselective Desymmetrization of Meso-Epoxides by 2‑Mercaptobenzothiazoles

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    Enantioselective desymmetrization of meso-epoxides by 2-mercaptobenzothiazoles was realized by using the pentacarboxycyclopentadiene-based chiral BrĂžnsted acid in combination of <i>N</i>-isopropylaniline as amine additive to give up to 90.5:9.5 er of the ring opening products

    SWI obtained in a 90-year-old man after heat stroke with a score of 6 in Glasgow Coma Scale.

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    <p>On the 4th day after admission, amplitude (A) and minIP (B) images show punctate hemorrhage detected in right frontal lobe.</p
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