• Title/Summary/Keyword: Deterioration factors

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Reviews About food Safety on Packaging Materials and Printing Ink Solvent (식품용 포장제와 인쇄 용제의 안정성에 관한 연구)

  • An, Duek-Jun;Kim, Youn-Uck;Park, Hoon
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.12 no.2
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    • pp.91-96
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    • 2006
  • The widespread use of packaging materials on food packages sometimes causes off-flavor and deterioration in the food by migration of packaging materials which consist of mainly plastic materials and printing ink solvents. Even though migration of the residual packaging materials does not generally cause safety problems in the contained food, it certainly can generate off-flavor and finally deteriorate quality of the finished product. In highly consumer-oriented markets, quality of the finished product is gaining more importance economically, so profound and thorough study about migration into food to maintain the fine quality of the end product becomes an importance issue. Studies have been conducted about migration of various packaging materials and the chemical reactions between the food components and the materials used for food packaging (Brody, 1989; Mcneal and Breder, 1987; Lawson, G and Lawson, C, 1996). Several of these studies have measured partition coefficient values (Kp) between packaging materials and various food samples and involved finding factors that affected the partitioning behavior of packaging materials into the contained food. However, to enable prediction of partitioning, data are still needed on the relation of packaging material chemical structure and properties to partitioning behavior, and on the partitioning behavior of various food ingredients and the total food compositions.

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Comparative Analysis of the Optical Aging Patterns in Different Partitions of the Beeswax-Treated Volume during Dry Heating Aging at $105^{\circ}C$ (건식 인공열화 시 밀랍본 시제품의 제본부위별 광학적 특성변화 비교분석)

  • Choi, Kyoung-Hwa;Jeong, Hye-Young;Kang, Yeong-Seok;Cho, Jung-Hye
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.3
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    • pp.98-105
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    • 2011
  • Patterns and levels of aging vary between the book volume and sheets, even though both are made from the same paper materials. In case of book format, the outside is more easily affected than inner side by environmental factors such as temperature, humidity and air. In this study, the change in optical properties after dry heating accelerated aging was comparatively analyzed to understand the difference of the optical aging characteristics between outside and inner side of the duplicated beeswax-treated volume. It is found that the cover pages of the beeswax-treated volumes were more optically deteriorated than their middle pages. This indicates that outer sides of aging book volume directly exposed to the air is more vulnerable to serious deterioration than inner sides. Also, aromatic compounds such as benzoic acid and cinnamic acid were observed in the investigation of UV/VIS absorbance of the beeswax in each aged sample.

Mechanism of Lipid Peroxidation in Meat and Meat Products -A Review

  • Min, B.;Ahn, D.U.
    • Food Science and Biotechnology
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    • v.14 no.1
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    • pp.152-163
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    • 2005
  • Lipid peroxidation is a primary cause of quality deterioration in meat and meat products. Free radical chain reaction is the mechanism of lipid peroxidation and reactive oxygen species (ROS) such as hydroxyl radical and hydroperoxyl radical are the major initiators of the chain reaction. Lipid peroxyl radical and alkoxyl radical formed from the initial reactions are also capable of abstracting a hydrogen atom from lipid molecules to initiate the chain reaction and propagating the chain reaction. Much attention has been paid to the role of iron as a primary catalyst of lipid peroxidation. Especially, heme proteins such as myoglobin and hemoglobin and "free" iron have been regarded as major catalysts for initiation, and iron-oxygen complexes (ferryl and perferryl radical) are even considered as initiators of lipid peroxidation in meat and meat products. Yet, which iron type and how iron is involved in lipid peroxidation in meat are still debatable. This review is focused on the potential roles of ROS and iron as primary initiators and a major catalyst, respectively, on the development of lipid peroxidation in meat and meat products. Effects of various other factors such as meat species, muscle type, fat content, oxygen availability, cooking, storage temperature, the presence of salt that affect lipid peroxidation in meat and meat products are also discussed.

Credit Risk Measurement Practices in Indian Commercial Banks - An Empirical Investigation

  • Arora, Swaranjeet
    • Asia-Pacific Journal of Business
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    • v.5 no.2
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    • pp.37-50
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    • 2014
  • Banking institutions have been facing variety of difficulties but the major cause of serious banking problems relates to lax credit standards for borrowers and counterparties, poor portfolio risk management, or a lack of attention to changes in economic or other circumstances that can lead to deterioration in the credit standing of a bank's counterparties. Although credit risk is an important factor that financial institutions should cope with, but the determinants of measuring credit risk have been studied less. This paper attempts to explore the determinants of credit risk measurement and to identify the factors that contribute to credit risk measurement practices in Indian banks and to compare credit risk measurement practices followed by Indian public and private sector banks, the empirical study has been conducted and views of employees of various banks have been tested using statistical tools. This study explored the phenomenon from different perspectives and revealed that single-name credit risk measurement and portfolio credit risk measurement are the key components that contribute to credit risk measurement in Indian banks. From the descriptive and analytical results, it can be concluded that Indian banks efficiently measure credit risk. The results also indicate that there is a significant difference between the Indian public and private sector banks in single-name credit risk measurement while, these banks do not significantly differ in portfolio credit risk measurement aspect.

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Salt Weathering Characteristics and Mechanism Interpretation of the Five-Storied Stone Pagoda in Tapri-ri, Uiseong (의성 탑리리 오층석탑의 염풍화 특성과 메커니즘 해석)

  • Lee, Mi Hey;Lee, Myeong Seong;Lee, Jae Man;Chun, Yu Gun
    • 보존과학연구
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    • s.33
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    • pp.57-67
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    • 2012
  • The Uiseong Tapriri Five-Storied stone pagoda has occurred exfoliation, granular disintegration and discoloration by physical and chemical weathering factors with the major deterioration occurring due to efflorescence by salt. According to the results of SEM-EDS and X-ray diffraction analysis, salts consists of gypsum, taranakite. Artificial salt weathering tests were carried out using the same type of rocks as those in the stone pagoda. The test results showed that efflorescence occurred on the surface of the rock, and that exfoliation and granular disintegration occurred inside the rock due to salt crystallization.

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An empirical study of the impact which the change of age ratio of disaster response organization has on organization effectiveness and quality assurance - Focused on field activities firefighters in Seoul metropolitan city - (재난대응조직 연령구성비 변화가 조직효과성 및 서비스질 보장활동에 미치는 영향에 관한 실증분석 - 서울지역 현장활동 소방공무원을 중심으로 -)

  • Park, Chan-Seok
    • Journal of the Korea Safety Management & Science
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    • v.16 no.4
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    • pp.133-145
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    • 2014
  • Aging of the fire organizations, typical disaster response agencies also will be in serious problems with aging society. It is expected that the ratio of more than fifties will reach 31~40% after 10~15 years in Seoul fire organization. This Aging of firefighters can bring about a serious problem in disaster and safety management, since firefighters require robust fitness and healthy bodies in disaster situations. In this study, after the analysis of aging status and trend of firefighters in Seoul, I have an empirical analysis about the impact this aging has on organization effectiveness and QA. As a result, the increase of the elderly reduced organization effectiveness and QA. In addition, in the group consisting of less than 50, it is expected to increase the organization's effectiveness and QA activities through field activity to improve the professional skills with age, but could not be confirmed. In the group consisting of more than fifties, it was found that aging had a significant negative impact on organizational effectiveness and QA activities as factors, including physical deterioration by aging.

Parameter Analysis and Modeling of Walking Loads (보행하중의 매개변수 분석 및 모형화)

  • 이동근;김기철;최균효
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2001.10a
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    • pp.459-466
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    • 2001
  • The floor vibration aspect for building structures which are in need of large open space are influenced by the interrelation between natural frequency and working loads. Structures with a long span and low natural frequency have a higher possibility of experiencing excessive vibration induced by dynamic excitation such as human activities. These excessive vibrations make the residents uncomfortable and the serviceability deterioration. Need formulation of loads data through actual measurement to apply walking loads that is form of dynamic load in structure analysis. The loads induced by human activities were classified into two types. First type is in place loads. the other type is moving loads. A series of laboratories experiments had been conducted to study the dynamic loads induced by human activities. The earlier works were mainly concerned to parameters study of dynamic loads. In this Paper, the walking loads have been directly measured by using the measuring plate in which two load cells were placed, the parameters, the load-time history of walking loads, and the dynamic load factors have been analyzed. Moreover, the shape of the harmonic loads which were gotten by decomposition the walking loads have been analyzed , and the walking loads modeling have been carried out by composition these harmonic loads derived by functional relation.

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Tc-To Method in Measurement of Concrete Crack (Tc-To법에 의한 콘크리트 균열측정)

  • 민정기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.39 no.3
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    • pp.108-114
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    • 1997
  • Concrete is said to have a high degree of extensibility when it is subjected to large deformations without cracking. The cracking behavior of concrete in the field may even be more complex. For example, in mass concrete compressive stresses are developed during the very early period when temperatures are rising, and the tensile stresses do not develop until at a later age when the temperature begins to decline. Actual cracking and failure depend on the combination of factors and indeed it is rarely that a single adverse factor is responsible for cracking of concrete. The importance of cracking and the minimum width at which a crack is considered significant depend on the conditions of exposure of the concrete. The ultrasonic pulse measurements can be used to detect the development of cracks in structures such as dams, and to check deterioration due to frost or chemical action. An estimate of the depth of a crack visible at the surface can be obtained by measuring the transit times across the crack for two different arrangements of the transducers placed on the surface. In this paper, the concrete cracks that artificially introduced crack width is 1 and 2mm, crack depth is 2, 4, 6, 8cm were measured by Tc-To Method In consequence, the measured depth was increased with increase of measuring distance from concrete crack. The most reliable results were shown when the introduced crack width was 1mm, and the measuring distance was 10cm from concrete crack.

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Assessment of water quality in an artificial urban canal: A case study of Songdo City in South Korea

  • Ahn, Jungkyu;Na, Yeji;Park, Sung Won
    • Environmental Engineering Research
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    • v.24 no.4
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    • pp.582-590
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    • 2019
  • Currently, the waterfront facility was constructed in New Songdo City, South Korea. It has the various water leisure areas and especially an artificial urban canal with filtered seawater by re-circulating flow system. However, due to excessive amount of nutrients from seawater combined with complicated geometry, it is highly vulnerable to deterioration of water quality. In this study, flow characteristics and pollutant transport were analyzed with comprehensive numerical models, MIKE 3 FM and ECO-lab. Based on these numerical results, notable sampling points were selected for field measurements and comparison between modeling and measured results were conducted. In addition, the integrated water quality evaluation index, Water Quality Index was applied to analyze various water quality issues. We also set up scenarios to control the two kinds of water quality factors, dissolved oxygen (DO), and total phosphorus (TP). As a result, the effect of 20% reduction of TP was less than 10% and it was almost ineffective for a year but it was reduced by up to 40% in case of scenario which DO is increased by 20%. Therefore, it was recommended to control the DO concentration, usually by applying re-aeration facility, rather than TP in artificial urban canal with seawater.

The Crack Control of Fiber Net Reinforced RC Slab (섬유망을 이용한 RC슬래브의 균열제어)

  • Bae, Ju-Seong;Kim, Kyoung-Soo;Kim, Nam-Wook;Kim, Chul-Min
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.6 no.2
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    • pp.225-231
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    • 2002
  • Severe cracks on Reinforced Concrete (RC) structures caused by structural displacement can be often one of the main reasons for the degradation of tensile and flexural rigidities of RC structures and for the deterioration of durability and serviceability of RC structures through accelerated steel corrosion. These combined factors adversely affect the performance of RC concrete, leading to shortened life time of RC structures. In consideration of these problems, we conducted 3 point bending experiments by employing three different types of concrete specimens: fiber-net reinforced concrete (FNRC), polypropylene-fiber reinforced concrete (PFRC), and plain concrete (PC). FNRC is well known for its strong corrosion resistance, light self-weight, and excellent tensile strength, while PFRC is known to be effective in crack control. FNRC was found to have the best first and final crack resistances followed by PFRC and PC, as evidenced by the highest initial crack load and the smallest final crack width, respectively. The FNRC specimens with various tensile strength of fiber net exhibited greater ultimate strengths than those for PFRC and PC. Furthermore, the crack widths of FNRC specimens were smaller than those calculated by the crack-width estimation equation of the KCI and ACI code. Therefore, we conclude that fiber net reinforcement is effective not only on crack control, but also on loading share.