• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.362-368
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• 2018

There is increased consumer demand for roasted seasoned laver Pyropia yezoensis, processed in various ways. The antioxidative activity of roasted seasoned laver was evaluated at different storage times and the quality of the roasted seasoned laver was improved. The laver was also heated at different temperatures for 3 seconds: $340^{\circ}C$ (SH340), $345^{\circ}C$ (SH345), $350^{\circ}C$ (SH350) and commercial roasted seasoned laver (D) was used as standard. The samples were stored in a transparent acrylic case ($39{\times}27{\times}18cm$) at room temperature for 10 weeks. The total phenolic content began to decrease after 7 weeks of storage and was 395.2, 386.4, 395.8 and $416.4{\mu}g/100g$ for SH340, SH345, SH350 and D, respectively. The respective DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity after 7 weeks of storage were 48.6%, 49.5%, 47.7% and 46.1%. The ferric reducing antioxidant power (FRAP) decreased rapidly after 7 weeks of storage due to the influence of sulfate groups. Therefore, the appropriate storage period and packaging method should be established based on these results.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.659-669
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• 2011

Objective: The aim of this study is to suggest a package layout guideline for low-floor bus by interview with passengers and observations of their behavior. Background: Increasing attention has been introduced the low-floor bus to be more suitable for use by transportation handicapped. Complex issues are involved in providing comfortable services to all people. We are going to suggest package layout guidelines for more comfortable and suitable travel to all people. Method: The two times of survey and video observation sessions were conducted on low-floor buses in Seoul; (1) a finding of potential issues in the first session, (2) a confirming of issues from the last session. Results: The three of major issues were founded in this study; (1) difficulties in supporting body when standing, (2) difficulties in sitting on front wheel pan seat, (3) difficulties in passing through the aisle. Conclusion: There were clear differences between public and transportation handicapped in using some tools which are used for support body such as roof hand rails, side hand rails, and hand rail rings. Some of design problems were founded to improve from the perspective of ergonomics and universal design. Such differences and design guidelines have to be considered in bus design as well as commercial vehicle. Application: The proposed design guidelines can be used to development of low-floor bus and other public transportations.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.491-496
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• 2012

Vegetable seeds are one of the most important key factors to determine the way of vegetable's production, distribution, processing and storage. Unfortunately, because of international exchange crisis in 1997, the most of main Korean seed companies were merged into foreign capitals. Currently, many domestic seed companies are incapable of their own survey and development of vegetable seed markets in foreign countries. To provide valuable seed market information for these companies, China, especially Yunnan and Guangdong provinces in China, was selected. Since China is one of the major vegetable seed importers. Also, Yunnan and Guangdong provinces are the most promising targets to export Korean vegetable seeds. The current status of vegetable production in China was analyzed with consideration of Yunnan and Guangdong provinces. The contents of survey and analysis are covering major vegetable crops' cultivation area, farm number, cultivation type, production amount, market price, farm income, packaging method, distribution type and amount of seed consumption. And particularly, major horticultural characteristics of leading varieties were presented to assist the development of exportable varieties of domestic seed companies. We assume the results of this study would be practically usable for the development of exportable varieties.

• BMB Reports
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• v.41 no.7
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• pp.511-515
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• 2008

The nucleocapsid (NC) protein of the Human Immunodeficiency Virus-1 plays a key role in viral genomic packaging by specifically recognizing the Psi($\Psi$) RNA sequence within the HIV-1 genome RNA. Recently, a novel cell-based assay was developed to probe the specific interactions in vivo between the NC and $\Psi$-RNA using E.coli cells (J. Virol. 81: 6151-55, 2007). In order to examine the extendibility of this cell-based assay to RNAs other than $\Psi$-RNA, this study tested the RNA aptamers isolated in vitro using the SELEX method, but whose specific binding ability to NC in a living cellular environment has not been established. The results demonstrate for the first time that each of those aptamer RNAs can bind specifically to NC in a NC zinc finger motif dependent manner within the cell. This confirms that the cell-based assay developed for NC-$\Psi$interaction can be further extended and applied to NC-binding RNAs other than $\Psi$-RNA.

• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.169-175
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• 1997

This study was carried out to assess the effect of the chlorine treatment into water for processing chicken products in each stage of slaughtering, with a special viewpoint related with reducing the viable number of microorganisms by which the water and the chicken body were contaminated. The mean bacterial number on chicken samples after picking process was log5.37$\pm$0.20~5.84$\pm$0.160CFU/$\textrm{cm}^2$. When assessed by standard plate count method, it was the higher one than any other processing stage in which eviscerating, pinning, packaging, and chilling was followed in order of the mean bacterial number. The coliform bacterial numbers on carcasses after sampling from different processing stages were log2.11$\pm$0.63~2.88$\pm$0.25MPN/$\textrm{cm}^2, which show almost similar numbers in each processing stage. But, after chilling process the number was decreased slightly. The bacterial counts in the water for scalding and chilling showed log3.43 $\pm$ 0.59~5.06$\pm$0.21 and log4.30$\pm$0.21~6.62$\pm$0.33CFU/$m\ell$, respectively. In the coliform counts for the water taken out from the 2nd chilling tank, the number was log1.97$\pm$0.35~2.91$\pm$0.22MPN/$m\ell$ which showed higher than those of the 1st and the 3rd chilling tank water. The effect of chlorination in reducing the bacterial numbers was accepted at the residual chlorine concentration of 1$m\ell$/$\ell$by showing the reduction from $10^8$ to $10^4$CFU level and the numbers were decreased less than 10CFU at the concentration of 5mg/$\ell$, when assessed by viable cell counts. In conclusion, these results suggested that chlorination In chilling water with final concentration of 5mg/$\ell$was strongly recommended to reduce the bacterial numbers on final chicken products.

• Korean Journal of Materials Research
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• v.25 no.3
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• pp.138-143
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• 2015

Aluminum nitride, a compound semiconductor, has a Wurtzite structure; good material properties such as high thermal conductivity, great electric conductivity, high dielectric breakdown strength, a wide energy band gap (6.2eV), a fast elastic wave speed; and excellent in thermal and chemical stability. Furthermore, the thermal expansion coefficient of the aluminum nitride is similar to those of Si and GaAs. Due to these characteristics, aluminum nitride can be applied to electric packaging components, dielectric materials, SAW (surface acoustic wave) devices, and photoelectric devices. In this study, we surveyed the crystallization and preferred orientation of AlN thin films with an X-ray diffractometer. To fabricate the AlN thin film, we used the magnetron sputtering method with $N_2$, NH3 and Ar. According to an increase in the partial pressures of $N_2$ and $NH_3$, Al was nitrified and deposited onto a substrate in a molecular form. When AlN was fabricated with $N_2$, it showed a c-axis orientation and tended toward a high orientation with an increase in the temperature. On the other hand, when AlN was fabricated with $NH_3$, it showed a-axis orientation. This result is coincident with the proposed mechanism. We fabricated AlN thin films with an a-axis orientation by controlling the sputtering electric power, $NH_3$ pressure, deposition speed, and substrate temperature. According to the proposed mechanism, we also fabricated AlN thin films which demonstrated high a-axis and c-axis orientations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3301-3306
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• 2012

In LED chip packaging, die bonding is a very important process which fixes the LED chip on the lead frame to provide enough strength for the next process. Conventional pick-up device of the die bonder is simply operated by up and down motion of a collet and an ejector pin. However, this method may cause undesired problems such as position misalignment and/or severe die damage when the pick-up device reaches the die. In this study, to minimize the position alignment error and die damage, a die bonder is developed by adopting a new pick-up head for precise alignment and high speed feeding. To evaluate structural stability of the designed system, required finite element model of the die bonder is generated, and structural analysis is performed. Vibration analysis of the pick-up head is also performed using developed finite element model at operation frequency range. As a result of the analysis, deformation, stress, and natural frequency of the die bonder are investigated.

• The Korean Journal of Applied Statistics
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• v.34 no.1
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• pp.99-114
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• 2021

With the Fourth Industrial Revolution based on new technology, the semiconductor manufacturing industry researches various analysis methods such as detecting process abnormalities and predicting yield based on equipment sensor data generated in the manufacturing process. The semiconductor manufacturing process consists of hundreds of processes and thousands of measurement processes associated with them, each of which has properties that cannot be defined by chemical or physical equations. In the individual measurement process, the actual measurement ratio does not exceed 0.1% to 5% of the target product, and it cannot be kept constant for each measurement point. For this reason, efforts are being made to determine whether to manage by using equipment sensor data that can indirectly determine the normal state of each step of the process. In this study, the Functional Data Analysis (FDA) was proposed to define a process abnormality detection process based on equipment sensor data and compensate for the disadvantages of the currently applied statistics-based diagnosis method. Anomaly detection accuracy was compared using machine learning on actual field case data, and its effectiveness was verified.

• Journal of the Korean Society of Food Culture
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• v.37 no.5
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• pp.429-437
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• 2022

This study evaluated the quality of school milk programs and analyzed the relative importance of school milk program selection attributes using conjoint analysis. The survey was conducted on students from middle and high schools in metropolitan cities that provide school milk programs. Responses were received from 414 students and the data was subjected to frequency analysis, t-test, and conjoint analysis using the SPSS Statistics Package. While evaluating white milk in the school milk program, middle school students rated 'packaging condition' (4.23) the highest, high school students rated 'nutrition' (4.64) the highest, and their evaluation of all the quality attributes was significantly different from that of middle school students (p<0.001). Overall satisfaction scores too, showed a significant difference between high school (4.46) and middle school students (4.01) (p<0.001). Processed milk & dairy products had the highest satisfaction score in the attribute of 'serving time' (4.57). The relative importance of the choice attributes of the school milk program was in the order of 'number per item' (62.260%), 'temperature' (25.708%), and 'serving method' (12.032%) for all students. The school milk program most preferred by all students and middle school students was to provide milk at a refrigerated temperature, select white milk three times a week, processed milk, fermented milk, and cheese twice a week, and provide it at the desired time.

• Food Science of Animal Resources
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• v.44 no.4
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• pp.779-789
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• 2024

The effects of irradiation on meat constituents including water, proteins, and lipids are multifaceted. Irradiation leads to the decomposition of water molecules, resulting in the formation of free radicals that can have both positive and negative effects on meat quality and storage. Although irradiation reduces the number of microorganisms and extends the shelf life of meat by damaging microbial DNA and cell membranes, it can also accelerate the oxidation of lipids and proteins, particularly sulfur-containing amino acids and unsaturated fatty acids. With regard to proteins, irradiation affects both myofibrillar and sarcoplasmic proteins. Myofibrillar proteins, such as actin and myosin, can undergo depolymerization and fragmentation, thereby altering protein solubility and structure. Sarcoplasmic proteins, including myoglobin, undergo structural changes that can alter meat color. Collagen, which is crucial for meat toughness, can undergo an increase in solubility owing to irradiation-induced degradation. The lipid content and composition are also influenced by irradiation, with unsaturated fatty acids being particularly vulnerable to oxidation. This process can lead to changes in the lipid quality and the production of off-odors. However, the effects of irradiation on lipid oxidation may vary depending on factors such as irradiation dose and packaging method. In summary, while irradiation can have beneficial effects, such as microbial reduction and shelf-life extension, it can also lead to changes in meat properties that need to be carefully managed to maintain quality and consumer acceptability.