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Comparison of Drying Yield, Meat Quality, Oxidation Stability and Sensory Properties of Bone-in Shell Loin Cut by Different Dry-aging Conditions

  • Cho, Soohyun;Kang, Sun-Moon;Kim, Yun-Seok;Kim, Young-Chun;Ba, Hoa Van;Seo, Hyun-Woo;Lee, Eun-Mi;Seong, Pil-Nam;Kim, Jin-Hyoung
    • Food Science of Animal Resources
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    • v.38 no.6
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    • pp.1131-1143
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    • 2018
  • This study aimed to investigate the drying yield, meat quality, oxidation stability and sensory properties of Hanwoo beef loin subjected to different dry-aging conditions. A total of 54 Hanwoo beef loins (bone-in, $6^{th}-13^{th}$ ribs) with fat cover at 2 d postmortem were assigned to four groups and hung in a dry-aging room at a controlled temperature ($2^{\circ}C-4^{\circ}C$), humidity (65%-85%) and air velocity (3 m/s). Four treatment conditions were tested; the respective temperature, humidity and treatment duration are as follows: T1, $2^{\circ}C$, 85%, 60 d; T2, $2^{\circ}C$, 65%, $20d+2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 20 d; T3, $2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 40 d; T4, $4^{\circ}C$, 85%, 60 d. The drying yield, total aerobic counts and fat contents increased, whereas the moisture content, meat color (CIE $L^*$, $a^*$, and $b^*$), and Warner-Bratzler shear force values decreased significantly during the aging period for all treatments (p<0.05). The cooking loss (%) did not change significantly until 40 d, and it was significantly higher in T1 and T4 than in T2 and T3 at 60 d (p<0.05). The water-holding capacity, pH and lipid oxidation [thiobarbituric acid reactive substance (TBARS) values] increased during aging (p<0.05). The sensory scores for tenderness, juiciness, flavor, and overall acceptability of dry-aged loin muscles increased as the aging period increased. T2 and T3 had significantly higher sensory scores and T1 had significantly lower scores for tenderness, juiciness, flavor, and overall acceptability at 20, 40, and 60 d for loin muscles (p<0.05).

The Preconsideration of Kiln for Firing Soft Stoneware in the Yeongnam Province in the Proto-Three Kingdoms Period (영남지방 원삼국시대의 토기가마구조에 대한 예찰)

  • Kim, Jae-cheol
    • Korean Journal of Heritage: History & Science
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    • v.40
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    • pp.35-72
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    • 2007
  • Since three has never been any incidence of having investigated kilns for firing soft stoneware in the proto-three kingdoms period so far, how they structured by reviewing historic literature and material was preconsidered in this study. It is presumed that after both Gimhae Daeseongdong-type and Sacheon Bonggyeri-type kilns for firing earthenware coexist early, through an internal alteration process which is mutually complex and momentous, the floor of plastic room has been flattened or slanted and expanded little by little into the closed-kiln structure. It seems that the structure of kilns for firing soft stoneware was a horizontal combustion type(水平燃燒式) and its plane shape was close to being rectangular in shape unlike that of kilns for firing stoneware found in Honam and Hoseo province in the period of (proto-) three kingdoms. On the other hand, it is likely that the horizontal combustion type structure of kilns for firing stoneware excavated in Samyong-ri, Jincheon preceded the vertical combustion type(垂直燃燒式)that of kilns for firing stonewere found in Sansu-ri. In addition, the term, monumeut for firing earthenware must be changed to kiln for firing earthenware and the terms of Pyeungyo(平窯) and Dyengyo(登窯) can be applied to kilns for firing tiles. Thus, it does not seem likely that the absolute equality that Wajil earthenware(soft stoneware) pottery is Pyeungyo and stoneware pottery is Dyeungyo is applied in all cases.

A Study on the Application of the New York Convention in the Recognition and Enforcement of ISDS Arbitral Awards (투자협정중재에 의한 중재판정의 승인·집행에 대한 뉴욕협약 적용에 관한 고찰)

  • Kang, Soo Mi
    • Journal of Arbitration Studies
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    • v.29 no.1
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    • pp.31-52
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    • 2019
  • As international transactions have grown more numerous, situations of disputes related to the transactions are getting more complicated and more diverse. Cost-effective remedies to settle the disputes through traditional methods such as adjudications of a court will be insufficient. There fore, nations are attempting to more efficiently solve investor-state disputes through arbitration under organizations such as the ICSID Convention, the ICSID Additionary Facility Rules, and the UNCITRAL Arbitration Rules by including the provisions on investor-state dispute settlement at the conclusion of an investment agreement. In case of an arbitration under the ICSID Convention, ICSID directly exercises the supervisorial function on arbitral proceedings, and there is no room for the intervention of national courts. In time of the arbitration where the ICSID Convention does not apply, however, the courts have to facilitate the arbitral proceedings. When the recognition and enforcement of an arbitral award under the ICSID Convention are guaranteed by the Convention, it should be considered that the New York Convention does not apply to them under the Convention Article 7 (1) fore-end. In exceptional cases in which an arbitral award under the ICSID Convention cannot be recognized or enforced by the Convention, the New York Convention applies to the recognition and enforcement because the award is not a domestic award of the country in which the recognition or enforcement is sought. It is up to an interpretation of the New York Convention whether the New York Convention applies to ISDS arbitral awards not based on the ICSID Convention or not. Although an act of the host country is about sovereign activities, a host country and the country an investor is in concurring to the investment agreement with the ISDS provisions is considered a surrender of sovereignty immunity, and it will not suffice to exclude the investment disputes from the scope of application of the New York Convention. If the party to the investment agreement has declared commercial reservation at its accession into the New York Convention, it should be viewed that the Convention applies to the recognition and enforcement of the ISDS awards to settle the disputes over an investitive act, inasmuch as the act will be considered as a commercial transaction. When the recognition and enforcement of an arbitral award on investment disputes about a nation's sovereign act have been sought in Korea and Korea has been designated the place of the investment agreement arbitration as a third country, it should be reviewed whether the disputes receive arbitrability under the Korean Arbitration Act or not.

Effect of 2-HEA and EGPA Composition on the Electro-optical Properties of Polymer Dispersed Liquid Crystal (아크릴계 단량체 2-HEA와 EGPA의 조성에 따른 고분자 분산형 액정(PDLC)의 전기광학적 특성 평가)

  • Choi, Jongseon;Kim, Young Dae;Kim, So Yeon
    • Applied Chemistry for Engineering
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    • v.30 no.2
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    • pp.205-211
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    • 2019
  • Over the past several decades, the polymer dispersed liquid crystal (PDLC) has received particular attention as a material for developing smart window due to their electro-optical switchable properties. In this study, PDLC cells were fabricated using acrylate monomers, namely 2-hydroxyethyl acrylate (2-HEA) and ethylene glycol phenyl ether acrylate (EGPA), and the effect of the monomer composition on their electro-optical properties was investigated. The monomer mixture with a low viscosity (~10 cps) was easily filled between indium tin oxide (ITO) glasses by capillary action at room temperature. PDLC cells prepared using the mixture ratio of 1 : 9 (2-HEA : EGPA) did not show a complete opaque state at a 0 V condition but exhibited unstable electro-optical properties under an electric field. As the LC composition increased in the reaction mixture for PDLC cell preparation, the $V_{th}$ (threshold voltage) and $V_{sat}$ (saturation voltage) values as well as contrast ratio (CR) increased. $V_{th}$ and $V_{sat}$ values also increased with the cell gap thickness. PDLC cells with a $20{\mu}m$ cell gap thickness exhibited higher CR than those with 10 and $40{\mu}m$ cell gap thicknesses. Particularly, PDLC cells prepared using the mixture ratio of 7 : 3 (2-HEA : EGPA) showed excellent electro-optical properties such as a low driving voltage and high contrast ratio.

Optimization of Elastic Modulus and Cure Characteristics of Composition for Die Attach Film (다이접착필름용 조성물의 탄성 계수 및 경화 특성 최적화)

  • Sung, Choonghyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.503-509
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    • 2019
  • The demand for smaller, faster, and multi-functional mobile devices in increasing at a rapidly increasing rate. In response to these trends, Stacked Chip Scale Package (SCSP) is used widely in the assembly industry. A film type adhesive called die attach film (DAF) is used widely for bonding chips in SCSP. The DAF requires high flowability at high die attachment temperatures for bonding chips on organic substrates, where the DAF needs to feel the gap depth, or for bonding the same sized dies, where the DAF needs to penetrate bonding wires. In this study, the mixture design of experiment (DOE) was performed for three raw materials to obtain the optimized DAF recipe for low elastic modulus at high temperature. Three components are acrylic polymer (SG-P3) and two solid epoxy resins (YD011 and YDCN500-1P) with different softening points. According to the DOE results, the elastic modulus at high temperature was influenced greatly by SG-P3. The elastic modulus at $100^{\circ}C$ decreased from 1.0 MPa to 0.2 MPa as the amount of SG-P3 was decreased by 20%. In contrast, the elastic modulus at room temperature was dominated by YD011, an epoxy with a higher softening point. The optimized DAF recipe showed approximately 98.4% pickup performance when a UV dicing tape was used. A DAF crack that occurred in curing was effectively suppressed through optimization of the cure accelerator amount and two-step cure schedule. The imizadole type accelerator showed better performance than the amine type accelerator.

The development of the 2020 Dietary Reference Intakes for Korean population: Lessons and challenges (2020 한국인 영양소 섭취기준 제·개정: 교훈과 도전)

  • Kwon, Oran;Kim, Hyesook;Kim, Jeongseon;Hwang, Ji-Yun;Lee, Jounghee;Yoon, Mi Ock
    • Journal of Nutrition and Health
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    • v.54 no.5
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    • pp.425-434
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    • 2021
  • The discovery of the relationship between nutrients and deficiency diseases during the 100 years from the mid-1800s to the mid-1900s was a breakthrough that led to advances in the study of nutrition. The Recommended Dietary Allowances (RDA) were created as a quantitative standard for avoiding diseases caused by nutrient deficiency. In addition, a reductionism paradigm has become generally accepted among nutrition scholars in health and disease, which focused on the properties of individual nutrients, content in foods, cellular levels, and mechanisms of action. The reductionist paradigm worked very well for the prevention and treatment of malnutrition diseases. However, as the incidence of nutrient deficiencies decreased and that of chronic diseases increased, the nutrition goals have been changed to secure safe and adequate nutrient intake and to reduce chronic disease risks. Accordingly, Dietary Reference Intakes (DRIs), a set of nutrient-based reference values, were designed to replace the RDA. The revised Korean DRIs were published for 40 nutrients in 2020. However, there is still room for improvement in the reference intake levels targeted at reducing the risk of chronic disease. The reductionist approach can no longer be practical because chronic diseases are related to the interactions between multi-components in the foods and multi-targets in the body. Therefore, a second innovative leap is needed following the nutrition development breakthrough made over 100 years ago. To this end, the nutrition paradigm must evolve from reductionism to a holism approach. Cutting-edge scientific technologies, such as metabolomics, transcriptomics, microbiomics, and bioinformatics, should also be acceptable in nutrition science based on the knowledge gained from basic nutrition studies.

A Study on the Cementation Reaction of Copper-containing Waste Etching Solution to the Shape of Iron Samples (철 샘플에 따른 구리 함유 폐에칭액의 시멘테이션 반응에 대한 연구)

  • Kim, Bo-Ram;Jang, Dae-Hwan;Kim, Dae-Weon
    • Clean Technology
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    • v.27 no.3
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    • pp.240-246
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    • 2021
  • The waste etching solution for chip on film (COF) contained about 3.5% copper, and it was recovered through cementation using iron samples. The effect of cementation with plate, chip, and powder iron samples was investigated. The molar ratio (m/r) of iron to copper was used as a variable in order to increase the recovery rate of copper. As the molar ratio increased, the copper content in the solution rapidly decreased at the beginning of the cementation reaction. Before and after the reaction, the copper content of the solution was determined by Inductively Coupled Plasma (ICP) using copper concentration according to time. After cementation at room temperature for 1 hour, the recovery rate of copper had increased the most in the iron powder sample, having the largest specific surface area of the samples, followed by the chip and plate samples. The recovered copper powder was characterized for its crystalline phase, morphology, and elemental composition by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS), respectively. Copper and unreacted iron were present together in the iron powder samples. The optimum condition for recovering copper was obtained using iron chips with a molar ratio of iron to copper of 4 giving a recovery rate of about 98.4%.

Evaluation of 12nm Ti Layer for Low Temperature Cu-Cu Bonding (저온 Cu-Cu본딩을 위한 12nm 티타늄 박막 특성 분석)

  • Park, Seungmin;Kim, Yoonho;Kim, Sarah Eunkyung
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.3
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    • pp.9-15
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    • 2021
  • Miniaturization of semiconductor devices has recently faced a physical limitation. To overcome this, 3D packaging in which semiconductor devices are vertically stacked has been actively developed. 3D packaging requires three unit processes of TSV, wafer grinding, and bonding, and among these, copper bonding is becoming very important for high performance and fine-pitch in 3D packaging. In this study, the effects of Ti nanolayer on the antioxidation of copper surface and low-temperature Cu bonding was investigated. The diffusion rate of Ti into Cu is faster than Cu into Ti in the temperature ranging from room temperature to 200℃, which shows that the titanium nanolayer can be effective for low-temperature copper bonding. The 12nm-thick titanium layer was uniformly deposited on the copper surface, and the surface roughness (Rq) was lowered from 4.1 nm to 3.2 nm. Cu bonding using Ti nanolayer was carried out at 200℃ for 1 hour, and then annealing at the same temperature and time. The average shear strength measured after bonding was 13.2 MPa.

Optimization of Plain Jacked Vessel Design in Adhesive Production Process Using Computational Fluid Dynamics (Computational Fluid Dynamics를 활용한 점/접착 생산 공정 내 Jacketed Vessel 설계 최적화)

  • Joo, Chonghyo;Park, Hyundo;Cho, Hyungtae;Kim, Junghwan
    • Applied Chemistry for Engineering
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    • v.31 no.6
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    • pp.596-602
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    • 2020
  • Blending process of adhesive production has a cooling process to cool down the temperature of the solution which was heated up to 76 ℃ with a mineral insulated (MI) cable by 30 ℃ at room temperature. Using a MI cable in the adhesive production process makes the production inefficient because it takes about 10 h for the cooling process. If a jacketed vessel is used instead of the MI cable, it would shorten the cooling downtime without any additional cooling system by using cold water. However, there are various types of jacketed vessels, and thus the most suitable type should be found before set up. In this study, we designed the optimized jacketed vessel for the adhesive production process by calculating the cooling downtime, which impacts production efficiency, as a function of the jacket types using computational fluid dynamics. As a result, the cooling performance of the plain jacket was 32.7% superior to that of the half-pipe coil jacket with the same height. In addition, the plain jacket with 60% spiral baffle reduced the cooling downtime and operating time by 80.4% and 25.1%, respectively.

Derivation of a Verification Formula for the Dose Rate Contributing to the Maze Door of the 6 MV Treatment Room (6 MV 치료실의 미로 도어에 기여하는 선량률의 검증식 유도)

  • Park, Cheol Seo;Kim, Jong Eon;Kang, Eun Bo
    • Journal of the Korean Society of Radiology
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    • v.15 no.1
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    • pp.85-91
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    • 2021
  • The purpose of this study is to derive an equation to verify the accuracy of the dose rate for each component calculated at the measurement point outside the maze door when designing the maze door of 6 MV X-ray beam. Based on the component-specific dose rate calculation formula for the measurement point outside the maze door described in NCRP Report 151 and IAEA Safety Report Series 47, the dose rate calculation formula for each component when applying the values of the drawing-based parameters and the dose rate calculation formula for each component when applying the values of conservative parameters are derived. From the two dose rate calculation formulas for each component, the dose rate verification formula for each component at the measurement point outside the maze door was derived. The resulting dose rate verification formula for each component at the measurement point outside the maze door can be compared and analyzed whether the dose rate for each component at the measurement point outside the maze door calculated by the designer falls within the range of the dose rate obtained from the derived dose rate verification formula for each component. This verification formula is considered to be practically useful in verifying the accuracy of the dose rate for each component calculated by the designer.