• Title/Summary/Keyword: moisture stability

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The appearance change and heat·moisture transfer properties of knitted fabric by yarn shrinkage (원사의 수축에 따른 다공성 편성물의 형태변화와 열·수분 전달특성)

  • Sang, Jeong-Seon;Park, Juhyun;Lee, Mee-Sik;Oh, Kyung Wha
    • The Research Journal of the Costume Culture
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    • v.25 no.6
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    • pp.880-892
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    • 2017
  • In this study, the appearance change and the heat moisture transfer properties of knitted fabric by yarn shrinkage were examined to obtain useful data on the development of thermo-sensitive functional materials. Eleven types of knitted fabric were knitted using highly bulky acrylic-blended yarn. After shrinking the specimens using dry heat treatment, the appearance change and thickness were measured. An HEC simulator was adopted for measuring the heat moisture transfer properties of specimens by yarn shrinkage. When holes were arranged vertically in the mesh structure, the specimens with 2,500 and 5,000 holes showed high percent change of hole area, appearance, and thickness. When holes were diagonally arranged in the mesh structure, the percent change of hole area in the specimen with 1,250 holes was larger than the one with 2,500 holes. However, the dimensional stability of the specimen with 2,500 holes was better because of its smaller appearance and thickness change. In the tuck structure, the percent change of hole area in the specimen with 625 and 416 holes was relatively large compared with the appearance and thickness change. Furthermore, the hole size in the tuck structure was smaller than that in the mesh structure but the percent change of hole area was larger. Therefore, it was proved that the tuck structure is more suitable than the mesh structure for developing thermo-sensitive functional materials. Heat moisture transfer property test verified that the change of hole area by yarn shrinkage enabled obtaining the thermal effect due to the distinct temperature difference in the inner layer.

A merging framework for improving field scale root-zone soil moisture measurement with Cosmic-ray neutron probe over Korean Peninsula

  • Nguyen, Hoang Hai;Choi, Minha
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.154-154
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    • 2019
  • Characterization of reliable field-scale root-zone soil moisture (RZSM) variability contribute to effective hydro-meterological monitoring. Although a promising cosmic-ray neutron probe (CRNP) holds the pontential for field-scale RZSM measurement, it is often restricted at deeper depths due to the non-unique sensitivity of CRNP-measured fast neutron signal to other hydrogen pools. In this study, a merging framework relied on coupling cosmic-ray soil moisture with a representative additional RZSM, was introduced to scale shallower CRNP effective depth to represent root-zone layer. We tested our proposed framework over a densely vegetated region in South Korea covering a network of one CRNP and nine in-situ point measurements. In particular, cosmic-ray soil moisture and ancillary RZSM retrieved from the most time stable location were considered as input datasets; whereas the remaining point locations were used to generate a reference RZSM product. The errors between these two input datasets and the reference were forecasted by a linear autoregressive model. A linear combination of forecasts was then employed to compute a suitable weight for merging two input products from the predicted errors. The performance of merging framework was evaluated against reference RZSM in comparison to the two original products and a commonly used exponential filter technique. The results of this study showed that merging framework outperformed other products, demonstrating its robustness in improving field-scale RZSM. Moreover, a strong relationship between the quality of input data and the performance merging framework in light of CRNP effective depth variation has been also underlined via the merging framework.

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NEAR INFRARED SPECTROSCOPY, A POWERFUL TECHNIQUE IN HUMAN SKIN STUDY : PART I METHOD RELIABILITY AND INFLUENTIAL PARAMETERS

  • Snieder, Marchel;Wiedemann, Sophie;Hansen, Wei G.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.3101-3101
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    • 2001
  • Near Infrared spectroscopy (NIR) used on human skin measurement was explored in the past decade. Many publications in different journals and magazines discussed the feasibility of the NIR technique for cosmetic product property studies. Based upon the results of pioneers, we have pursued some work of the NIR instrument coupled with a probe module for skin measurement in vivo and vitro. In part I of this paper, the specific Near Infrared spectroscopy instrument stability, human subject conditions and other parameters, which could affect the measurements reproducibility are discussed. Second derivative NIR spectra and Principle Components Analysis (PCA) are utilised for data interpretation. In part II of this paper, the relationship of human skin moisture and ageing, the gender information and finally, the discovery of penetration depth of NIR incident light on skin are reported. A theoretical penetration depth calculation equation is proposed. In part III, the study results of a couple of commercial skin care products effect will be described. The skin lotions were applied on human skin (in vivo) in order to exam the NIR feasibility to monitor the changes of moisture level. The results are consistently positive. From our primary study, it can conclude that the NIR is potentially a very powerful instrument for skin condition diagnostics, either for cosmetic and/or for medication purposes.

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Improving Texture and Storage Stability of Chinese-Style Pork Jerky by the Addition of Humectants

  • Chen, W.S.;Liu, D.C.;Chen, M.T.;Ockerman, H.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.10
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    • pp.1455-1460
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    • 2000
  • Chinese-style pork jerky with different levels (3, 6 and 9%) of glycerol or sorbitol were prepared. Moisture content, water activity ($a_w$) and shear value decreased with the addition of glycerol or sorbitol. During storage at $28^{\circ}C$ thiobarbituric acid (TBA) value of all samples declined with the addition of glycerol or sorbitol during storage time. After storage at room temperature ($28^{\circ}C$) for 180 days, the volatile basic nitrogen (VBN) of all treated products were less than the control group. In addition, the mold and yeast growth were inhibited slightly with the addition of glycerol or sorbitol. The absorption isotherm of pork jerky with different levels of glycerol at $25^{\circ}C$ had an aw above 0.75, and moisture contents at 6 and 9% which were higher than the control group. The moisture content was less than the control group with the addition of sorbitol. The chewiness desirability score of pork jerky with 6% glycerol was higher than the other treatments. However, no differences in hardness desirability score due to treatments were detected by sensory panelists.

Lactic Acid Bacteria Mixture as Inoculants on Low Moisture Italian Ryegrass Silage Fermentation

  • Soundharrajan, Ilavenil;Kuppusamy, Palaniselvam;Park, Hyung Soo;Kim, Ji Hea;Kim, Won Ho;Jung, Jeong Sung;Choi, Ki Choon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.3
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    • pp.127-131
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    • 2019
  • The effects of lactic acid bacteria (LAB) mixtures on low moisture Italian ryegrass (IRG) silage fermentation was evaluated in field conditions. The experiment was categorized into two groups: Un-inoculated (Control) and Inoculated with LAB mixture for four storage periods (45, 90, 180, and 365 days, respectively). Silage inoculated with the LAB mixture had the lowest pH with highest lactic acid production than the control from beginning at 45-365 days at all moistures. Higher LAB counts were observed in inoculated silages than the control silages at whole experimental periods. It is a key reason for the rapid acidification and higher lactic acid production in silages during the storage periods. Overall results suggest that an adding of LAB mixture had positive effects on the increasing aerobic stability of silage and preserved its quality for an extended duration.

Year-long Feeding of Silage and Stability of Feed Quality (사일리지의 연간급여와 사료성분의 안정성)

  • 성경일
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.1
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    • pp.19-25
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

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Year-long Feeding of Silage and Stability of Feed Quality (사일리지의 연간급여와 사료성분의 안정성)

  • 성경일
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.1
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    • pp.19.1-19.1
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

Parametric Resonance Characteristics of Laminated Composite Curved Shell Panels in a Hygrothermal Environment

  • Sahu, S.K.;Rath, M.K.;Datta, P.K.;Sahoo, R.
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.3
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    • pp.332-348
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    • 2012
  • The present study deals with the parametric resonance behaviour of laminated composite curved shell panels in a hygrothermal environment using Bolotin's approach. A simple laminated model is developed using first order shear deformation theory (FSDT) for the vibration and dynamic stability analysis of laminated composite shells subjected to hygrothermal conditions. A computer program based on the finite element method (FEM) in a MATLAB environment is developed to perform all necessary computations. Quantitative results are presented to show the effects of curvature, ply-orientations, degree of orthotropy and geometry of laminates on the parametric instability of composite curved shell panels for different temperature and moisture concentrations. The excitation frequencies of laminated composite panels decrease with the increase of temperature and moisture due to reduction of stiffness for all laminates.

Dynamic modeling of a drying cylinder in Paper Plants (제지공정 내 건조 실린더의 동적 모사)

  • Gwak, Gi-Yeong;Yeo, Yeong-Gu;Kim, Yeong-Gon;Choe, Gyeong-Seok;Gang, Hong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2004.04a
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    • pp.117-126
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    • 2004
  • This paper presents a linear model for heat transfer processes in the drying cylinders and the web in papar mill. The PDE model, functions include steam temperatures, wet temperatures, moisture constents, reel speed and basis weight were derived from operation data. The changes of wet temperatures and moisture contents in the drying cylinders and wets could be described. The Transfer function can be obtained through the state space model derived from the linearized PDE model. Stability of the drying cylinder model for paper plants and analysis of characteristics of process responses for changes in input variables are investigated.

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Characteristics of Water Vapor Sorption Phenomena of Powdered Foods (건조분말 식품의 수분 특성에 관한 비교 연구)

  • 박길동;김동원
    • Journal of Ginseng Research
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    • v.6 no.1
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    • pp.30-37
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    • 1982
  • This study was conducted to investigate the water vapor permeability of packaging film, Al- foil laminated paper, and sorption properties of dehydrated and powdered foods. The results are as fellows. 1. Absorption rate of each products was greately affeoted by physicochemical properties of foods rather than initial moisture contents of the products. 2. The absorption rate of each products were in the order of freeze dried coffee, spray dried coffee, freeze drie4 ginseng extract, spray dried ginseng extract, ginger tea, black tea, citrus juice Powder and ssang wha tea. 3. Most of the products such as freeze dried coffee, spray dried coffee, freeze dried ginseng extract, ginger tea and black tea have shorter than a month of shelf life. 4. The stability of the products were greatly affected by its desorption properties than the degree of desorption of moisture. 5. Water vapor permeability of packaging materials which are laminated Al-foil with polythylene and glassin paper were mainly affected of thickness of Al-foil and polyethylene.

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