• Title/Summary/Keyword: C-value

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Shelf-Life Extension of Sing Sing Hoe (Fresh Sliced Raw Fish) by Frozen Storage (냉동저장을 통한 싱싱회 저장기간 연장에 관한 연구)

  • Park, Jin-Il;Yoon, So-Mi;Yoon, Ho-Dong;Park, Hee-Yeon;Byun, Han-Seok;Jang, Mi-Soon
    • Food Science and Preservation
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    • v.16 no.6
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    • pp.824-829
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    • 2009
  • Changes in pH, viable microbial count, chemical freshness, texture, and sensory qualities of Sing Sing Hoe (SSH, fresh-sliced raw fish) were measured over 15 days at $4^{\circ}C$, $-20^{\circ}C$, and $-80^{\circ}C$. The initial pH of SSH was 6.25 at all three storage temperatures, and pH increased slightly after 12 days to pH 6.48 and pH 6.55 at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. The range in viable cell count was 104-106 CFU/g, regardless of storage temperature. The initial content of volatile basic nitrogen (VBN) was 5.8 mg/100 g and became 8.2 mg/100 g or less, and 7.9 mg/100 g or less after 15 days at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. However, pH and VBN values increased significantly after 3 days of storage at $4^{\circ}C$. At this temperature, the K-value was 22.3% after 6 days and 40% or more after 15 days. At $-20^{\circ}C$, the K-value was 9.6% or less after 6 days and 21% or less after 15 days of storage. At $-80^{\circ}C$, the K-value was 8.5% or less after 9 days and 20% or less after 15 days of storage. Compared with the K-value of live fish muscle (10%), freshness similar to that of live fish was maintained for 6 days under both $-20^{\circ}C$ and $-80^{\circ}C$ storage conditions. There was no significant change in texture during storage of SSH at $-20^{\circ}C$ or $-80^{\circ}C$, but SSH stored at $4^{\circ}C$ showed a decrease in texture quality during storage. Sensory scores were high for material stored for up to 3 days at $4^{\circ}C$ and 6 days at $-20^{\circ}C$ or $-80^{\circ}C$. The overall freshness of SSH was maintained for up to 6 days, in comparison with fresh-sliced raw fish, under both frozen storage conditions.

The Changes in the Chemical Composition of Lipid in Hair-tail Muscle on Sun-Drying (갈치육(肉)의 일광건조중(日光乾燥中) 지질(脂質)의 화학적(化學的) 변화(變化)에 관(關)한 연구(硏究))

  • Namkung, Sok;Lee, Young-Ja;Ahn, Myoung-Soo
    • Journal of Nutrition and Health
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    • v.13 no.1
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    • pp.65-69
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    • 1980
  • When the Hair-tail was dried in the direct sunlight, the changes of acid value, TBA value, peroxide value and fatty acid composition of its muscle were observed. The results of the observation were as follows: 1) Total content of the lipid in the fresh Hair-tai1 was 9.91%, that of saturated fatty acid was 43.3%, and that of unsaturated fatty acid was 56.7%. The TBA value, the peroxide value and acid value were slowly increased until the 4th week, then were somewhat quickly increased in the 5th week. 2) The analysis of the fatty acid composition of the fresh Hair-tail lipid by meas of G.L.C method showed the order of the content quantities such as $C_{18}\;:\;1(44.3%),$ $C_{16}(29.22%),$ $C_{16}\;:\;1(11.3%),$ $C_{14}(6.6%),$ $C_{18}(5.4%),$ $C_{17}(2%),$ $C_{17}\;:\;1(1.1%),$ $C_{18}(2%),$ were found to be a trace. 3) The content of the unsaturated fatty acid was shown to be decreased while the level of the saturated fatty acid was increased during the sun drying.

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Effects of Retort Sterilization on Quality Characteristics of the Imitation Crab Leg (레토르트 살균처리가 게맛어묵의 품질특성에 미치는 영향)

  • Kang, Jin-Yeong;Yun, Jae-Ung;Hwang, Seok-Min;Kang, Jeong-Gu;Kim, Nam-Woo;Oh, Kwang-Soo
    • Journal of agriculture & life science
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    • v.44 no.6
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    • pp.147-157
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    • 2010
  • This study was carried out to develop the normal temperature-circulatable retort sterilized imitation crab leg (RSIC) with long shelf-life by retort sterilization. We have examined the optimum retort sterilization conditions and quality characteristics of the RSIC. Central composite design for response surface methodology (RSM) was adopted for optimization of retort sterilization, and experimental central composite design consisted of 11 samples such as 4 factorial points; 4 star points; 3 central points. Sterilization temperature and $F_0-value$ for retort sterilization were chosen for independent variables, and shearing force, whiteness and sensory score about texture were selected as a dependent variable. As a results of RSM analysis, multiple response optimization for the RSIC by Minitap statistical programing was $F_0-value$ 3.3 min. at $117.5{^{\circ}C}$. Also RSM analysis indicated such as sterilization temperature during retort sterilization was the most influential factor, while $F_0-value$ little affected on quality of the RSIC.

The Changes of Lipid Oxidation and Fatty Acid Composition of Extruded Pellet Feed by Dietary Moisture Level and Storage Temperature (수분함량과 저장온도에 따른 배합사료의 지방산화 및 지방산 조성 변화)

  • Jang, Mi-Soon;Kim, Kyoung-Duck;Kim, Kang-Woong;Lee, Jong-Yun;Kang, Yong-Jin
    • Journal of Aquaculture
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    • v.21 no.4
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    • pp.226-233
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    • 2008
  • This study investigated the effects of dietary moisture level and storage temperature on lipid oxidation and fatty acids composition of the extruded pellet feed. The diets containing the moisture levels of 5%, 15% and 25% were prepared by adding moisture (water) to the commercial extruded pellets and stored at $5^{\circ}C$, $20^{\circ}C$ (room temperature) and $35^{\circ}C$. The samples for analysis were collected at every 2 days for 10 days. Acid value (AV), peroxide value (POV), 2-thiobarbituric acid (TBA) value and fatty acid composition of the feeds were measured. No differences in the AV, POV and TBA value were observed in feed containing 5% moisture at all storage temperatures for 10 days. However, the AV, POV and TBA value of diets containing 15% and 25% moisture increased rapidly at $20^{\circ}C$ and $35^{\circ}C$ after 4 days. Fatty acids compositions of feeds containing 5% moisture did not change during the storage periods at $5^{\circ}C$ and $20^{\circ}C$. However, 5% moisture feed stored at $35^{\circ}C$ increased monoene fatty acid content and decreased the contents of polyene fatty acid, PUFA (polyunsaturated fatty acid)/SFA (saturated fatty acid) and $(C_{20:5}+C_{22:6})/C_{16:0}$ after 4 days. Also, 15% moisture feed stored at $35^{\circ}C$ showed increased monoene fatty acid content and decreased $(C_{20:5}+C_{22:6})/C_{16:0}$ after 2 days. The diet containing 25% moisture showed increased monoene fatty acid content and decreased contents of PUFA, PUFA/SFA and $(C_{20:5}+C_{22:6})/C_{16:0}$ at all temperatures after 2 days. In this study, lipid oxidation can occur in the extruded pellet feeds of 15% and 25% moisture at room temperature after 2 days.

Electrical Properties of SiC Composites by Transition Metal (천이금속에 따른 SiC계 복합체의 전기적 특성)

  • Shin, Yong-Deok;Seo, Je-Ho;Ju, Jin-Young;Ko, Tae-Hun;Kim, Young-Bek
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1303-1304
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    • 2007
  • The composites were fabricated, respectively, using 61[vol.%]SiC-39[vol.%]$TiB_2$ and using 61[vol.%]SiC-39[vol.%]$ZrB_2$ powders with the liquid forming additives of 12[wt%] $Al_{2}O_{3}+Y_{2}O_{3}$ by hot pressing annealing at $1650[^{\circ}C]$ for 4 hours. Reactions between SiC and transition metal $TiB_2$, $ZrB_2$ were not observed in this microstructure. ${\beta}{\rightarrow}{\alpha}$-SiC phase transformation was occurred on the SiC-$TiB_2$ and SiC-$ZrB_2$ composite. The relative density, the flexural strength and Young's modulus showed the highest value of 98.57[%], 226.06[Mpa] and 86.38[Gpa] in SiC-$ZrB_2$ composite at room temperature respectively. The electrical resistivity showed the lowest value of $7.96{\times}10^{-4}[{\Omega}{\cdot}cm]$ for SiC-$ZrB_2$ composite at $25[^{\circ}C]$. The electrical resistivity of the SiC-$TiB_2$ and SiC-$ZrB_2$ composite was all positive temperature coefficient resistance (PTCR) in the temperature ranges from $25[^{\circ}C]$ to $700[^{\circ}C]$. The resistance temperature coefficient of composite showed the value of $6.88{\times}10^{-3}/[^{\circ}C]$ and $3.57{\times}10^{-3}/[^{\circ}C]$ for SiC-$ZrB_2$ and SiC-$TiB_2$ composite in the temperature ranges from $25[^{\circ}C]$ to $700[^{\circ}C]$.

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A Distcussion on the Size Deviation Test of Raw Silk (生絲纖度檢査規定에 關한 考察)

  • Choi, Jin-Sub
    • Journal of Sericultural and Entomological Science
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    • v.25 no.1
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    • pp.44-50
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    • 1983
  • The study was carried out to suggest on opinion of the standardization of size deviation in the existing raw silk testing method. 1. The present grade A of size deviation stipulates 4.61 to 5.80 of standard deviation for 50 to 69 denier of mean value, however, the 5.80 standard deviation with the mean values of 50 and 69 denier belong to different distribution. 2. It is reasonable that the variation coefficients of grade 2A should be lower than that of grade A. However, the present testing method shows larger variation in grade 2A than in grade A. This is illustrated 9.00 for 69 denier in grade 2A and 8.41 for 70 denier in grade A. 3. The size deviation value compares the quality of raw silk with different mean value. Therefore, the standard deviation is recommended to be replaced by the C.V. value in determining the grade of silk. 4. The C.V. have a tendency to increase with lower grades below 6A for the size deviation below 33 denier with some inconsistencies. The figures should be adjusted so that the C.V. inconsistencies size deviation below 33 denier will be corrected. 5. The standard deviation increases with size under the same grade for the size deviations above 33 denier, however, the C.V. does not vary greatly with size deviation. 6. To rectify the above-mentioned inconsistencies the C.V. conversion and curvilinear regresion correction is recommended to improve the present silk testing method 7. The table of size deviation standard are as follows: Suggested standard of size deviation, unit: C.V. Value

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Effect of Aging Heat Treatment on the Mechanical Properties in Inconel 718 Alloy (Inconel 718 합금의 시효열처리가 기계적 성질에 미치는 영향)

  • Kang, Hee Jae;Kim, Jung Min;Jee, Sung Hwan;Sung, Jie Hyun;Kim, Young Hee;Sung, Jang Hyun;Jeon, Eon Chan
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.3
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    • pp.271-277
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    • 2013
  • Inconel 718 super alloy was aging heat treated at the temperature range from $675^{\circ}C$ to $785^{\circ}C$ for 5~40 hours after solution annealing at $1025^{\circ}C$ for 1 hour. The aging treated specimens were investigated microstructure, mechanical properties and thermal expansion/contraction. Precipitates appeared for a long time aging treatment were niobium carbide and also ${\gamma}^{\prime}$ phase. For the aging treatment time of 10 hours, the changes in strength and hardness with increasing aging treatment temperature showed the maximum value at the temperature of $725^{\circ}C$. This maximum value is to be related with the precipitation of ${\gamma}^{\prime}$ and ${\gamma}^{{\prime}{\prime}}$ phases. The decrease in strength, elongation and hardness during long time aging at $725^{\circ}C$ were thought to be induced from the coarsening of the grain size and the transformation of ${\gamma}^{{\prime}{\prime}}$ phase to ${\gamma}^{\prime}$ phase. For the specimens treated for 10 hours, impact energy showed constant value of ~105 J with increasing the aging temperature, however this value continuously decreased with elapsing time at the aging temperature of $725^{\circ}C$. It was found that the decrease in impact value was induced from the coarsening of grain size and the carbide coarsening. The coefficient of thermal expansion of aging treated Inconel 718 alloy increased with raising test temperature, and the coefficient was appeared $11.57{\sim}12.09{\mu}m/m{\cdot}^{\circ}C$ and $14.28{\sim}14.39{\mu}m/m{\cdot}^{\circ}C$, respectively, after heating to $150^{\circ}C$ and $450^{\circ}C$.

Data Build-up for the Construction of Korean Specific Greenhouse Gas Emission Inventory in Livestock Categories

  • Won, S.G.;Cho, W.S.;Lee, J.E.;Park, K.H.;Ra, C.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.3
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    • pp.439-446
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    • 2014
  • Many studies on methane ($CH_4$) and nitrous oxide ($N_2O$) emissions from livestock industries have revealed that livestock production directly contributes to greenhouse gas (GHG) emissions through enteric fermentation and manure management, which causes negative impacts on animal environment sustainability. In the present study, three essential values for GHG emission were measured; i.e., i) maximum $CH_4$ producing capacity at mesophilic temperature ($37^{\circ}C$) from anaerobically stored manure in livestock category ($B_{0,KM}$, Korean livestock manure for $B_0$), ii) $EF_{3(s)}$ value representing an emission factor for direct $N_2O$ emissions from manure management system S in the country, kg $N_2O-N$ kg $N^{-1}$, at mesophilic ($37^{\circ}C$) and thermophilic ($55^{\circ}C$) temperatures, and iii) $N_{ex(T)}$ emissions showing annual N excretion for livestock category T, kg N $animal^{-1}$ $yr^{-1}$, from different livestock manure. Static incubation with and without aeration was performed to obtain the $N_2O$ and $CH_4$ emissions from each sample, respectively. Chemical compositions of pre- and post- incubated manure were analyzed. Contents of total solids (% TS) and volatile solid (% VS), and the ratio of carbon to nitrogen (C/N) decrease significantly in all the samples by C-containing biogas generation, whereas moisture content (%) and pH increased after incubation. A big difference of total nitrogen content was not observed in pre- and post-incubation during $CH_4$ and $N_2O$ emissions. $CH_4$ emissions (g $CH_4$ kg VS-1) from all the three manures (sows, layers and Korean cattle) were different and high C/N ratio resulted in high $CH_4$ emission. Similarly, $N_2O$ emission was found to be affected by % VS, pH, and temperature. The $B_{0,KM}$ values for sows, layers, and Korean cattle obtained at $37^{\circ}C$ are 0.0579, 0.0006, and 0.0828 $m^3$ $CH_4$ kg $VS^{-1}$, respectively, which are much less than the default values in IPCC guideline (GL) except the value from Korean cattle. For sows and Korean cattle, $N_{ex(T)}$ values of 7.67 and 28.19 kg N $yr^{-1}$, respectively, are 2.5 fold less than those values in IPCC GL as well. However, $N_{ex(T)}$ value of layers 0.63 kg N $yr^{-1}$ is very similar to the default value of 0.6 kg N $yr^{-1}$ in IPCC GLs for National greenhouse gas inventories for countries such as South Korea/Asia. The $EF_{3(s)}$ value obtained at $37^{\circ}C$ and $55^{\circ}C$ were found to be far less than the default value.

A Study on the Quality Assuranc of Chemical Analysis Data of Precipitation Samples (강수 분석자료의 신뢰성 검토에 관한 연구)

  • 강공언
    • Journal of environmental and Sanitary engineering
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    • v.10 no.3
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    • pp.85-98
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    • 1995
  • In order to ensure that all major cations and anions were accurately measured, the quality assurance checks of chemical analysis data by considering ion and conductivity balance of each precipitation sample were performed. To check the quality assurance of chemical analysis data, precipitation samples were collected by wet- only precipitation sampler at Seoul site and their chemical components were analyzed. By checking the problems for the screening methods of chemical analysis data used until recently, the f value expressed as the ratio of the sum of cations and anions equivalent concentration( $\Sigma $C/$\Sigma $A ) was found to be not ap priorate for data screening. Also, the scattering plot between cation and anion equivalent concentrations in each sample was found to show the general tendency of ion balance but was proved to not quantitate the standard of data screening at a set of samples of various concentration levels.4 more appropriate value was therefore required, h value is defined as (A-C)/C for C≥A and ( A-C)/A for C<4. This value was showed to check the ion balance in a viewpoint of quantitative as well as qualitative and to be useful in applying this expression to a measurement data set. However, the standard o( data screening must vary in response to the ion concentration of sample. In this study, the quality assurance of chemical analysis data was checked by considering both the ion balance evaluating by h value and the electrical conductivity. As these quality assurance checks were applied to Seoul data serf 67 valid samples were obtained. The result of statistical summary in the analytical parameter of precipitation samples collected for a certain period was found to be computed in the precipitation volume- weighted mean( VWM) rather than the arithmetic mean( AM), but PH In the VWM of hydrogen ion concentration. The annual VWM of pH values was 5.0(4.9 ∼ 5.1).

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Value Chain Analysis of Geospatial Web Service for VGI Application (사용자 참여형 공간정보 웹서비스의 가치사슬분석)

  • Choi, Won Wook;Hong, Sang Ki;Ahn, Jong Wook
    • Spatial Information Research
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    • v.22 no.2
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    • pp.73-87
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    • 2014
  • The fact that the limits of information recency, diversity, and usability are mainly caused by the supply oriented geospatial data and service development is commonly recognized. It is recently tried to overcome the limits by facilitating user experience and VGI(Volunteered Geographic Information) in several geospatial web services. This study suggests 10C framework of geospatial web service for VGI through review and examination of previous research. Based on the 10C framework, the value chain system of 23 use cases relevant to the geospatial web service involving the creation of user's VGI is investigated. The result of the value chain analysis is applied to examine and formulate the strategies to generate value addition from public spatial information with respect to creation, aggregation, delivery, and consumption process of VGI.