• Title/Summary/Keyword: Quality stability

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Effect of Applying Molasses and Propionic Acid on Fermentation Quality and Aerobic Stability of Total Mixed Ration Silage Prepared with Whole-plant Corn in Tibet

  • Chen, Lei;Guo, Gang;Yuan, Xianjun;Shimojo, Masataka;Yu, Chengqun;Shao, Tao
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.3
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    • pp.349-356
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    • 2014
  • The objective of this study was to evaluate the effects of molasses and propionic acid on the fermentation quality and aerobic stability of total mixed ration (TMR) silages prepared with whole-plant corn in Tibet. TMR (354 g/kg DM) was ensiled with four different treatments: no additive (control), molasses (M), propionic acid (P), and molasses+propionic acid (PM), in laboratory silos (250 mL) and fermented for 45 d. Silos were opened and silages were subjected to an aerobic stability test for 12 days, in which chemical and microbiological parameters of TMR silages were measured to determined the aerobic deterioration. After 45 d of ensiling, the four TMR silages were of good quality with low pH value and ammonia/total N (AN), and high lactic acid (LA) content and V-scores. M silage showed the highest (p<0.05) LA content and higher dry matter (DM) recovery than the control and P silages. P silage had lower (p<0.05) LA content than the control silage. During aerobic exposure, lactic acid contents decreased gradually in the control and M silages, while that of P and PM silages increased, and the peak values were observed after 9 d. M silage had similar yeast counts with the control silage (> $10^5$ cfu/g FM), however, it appeared to be more stable as indicated by a delayed pH value increase. P and PM silages showed fewer yeasts (< $10^5$ cfu/g FM) (p<0.05) and were more stable than the control and M silages during aerobic exposure. It was concluded that M application increased LA content and improved aerobic stability of TMR silage prepared with whole-plant corn in Tibet. P application inhibited lactic acid production during ensiling, and apparently preserved available sugars which stimulated large increases in lactic acid during aerobic exposure stage, which resulted in greater aerobic stability of TMR silage.

A Study on Suspension Optimization of the Korean Personal Rapid Transit Vehicle (한국형 PRT차량의 현가장치 최적화 연구)

  • Kim, Hyun Tae;Kim, Jun Woo;Cho, Jeong Gil;Koo, Jeong Seo;Kang, Seokwon;Jeong, Raggyo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.40 no.3
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    • pp.317-326
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    • 2016
  • In this study, running stability and ride quality analyses, applying the 'ISO 3888 (double lane change)' and 'ISO 2631-1' (mechanical vibration and shock) tests, were performed for the suspension optimization of the Korean personal rapid transit (PRT) vehicle. The suspension optimization results for running stability and ride quality were derived by applying the multiresponse surface method. From the comparisons of the optimization results for different ratios of the objective functions of running stability and ride quality, we derived the best objective function ratio of 3.9-to-6.1 to improve both the running stability and the ride quality. With the optimized results, the suspension stiffness became 30.68 N/mm, between the value of the $S_2$ and $S_3$ models, and the damping coefficient equaled that of the $D_1$ model. When compared with the suspension of the current PRT vehicle, the roll angle, yaw rate, sideslip angle, and ride comfort were improved by 0.37, 0.37, 2.8, and 5, respectively.

Optimization and Evaluation of Flight Control Laws to Satisfy Longitudinal Handling Quality and Stability Margin Requirements (종축 비행성 요구도 및 안정성 여유 만족을 위한 비행제어법칙 최적화 및 평가)

  • Kim, Seong Hyeon;Ko, Deuk Won;Lee, Tae Hyun;Kim, Dong Hwan;Kim, Byoung Soo
    • Journal of Aerospace System Engineering
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    • v.15 no.5
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    • pp.8-15
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    • 2021
  • This paper describes a design method using an optimization technique to satisfy the longitudinal handling quality of high maneuverable jet aircraft. The dynamic inversion technique was applied to the target aircraft, and the control gain optimization satisfied the longitudinal short-period handling quality, however, the stability margin was not considered. If the stability margin is not satisfied, it is necessary to directly readjust the gains through trial and error methods for improvement. To improve this, an additional compensator and an optimization constraint were added to the control gain optimization procedure. In addition, the degree of handling quality satisfaction with the optimization result was reevaluated, and additional control evaluation criteria for the convergence of the time response and the steady state error that the flight performance requirement set as the optimization constraint cannot be reflected, and the results are described.

Effect of Storage Temperature and Humidity on the Quality Stability of Potatoes (감자의 품질안정성에 대한 저장 온.습도의 영향)

  • 권중호;변명우
    • Food Science and Preservation
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    • v.2 no.2
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    • pp.243-249
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    • 1995
  • Potatoes, Irish cobbler, were subject to quality evaluation from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 11 months. Quality criteria were sprouting, rotting, weight changes, moisture, total sugar, reducing sugar and vitamin C. Low temperature condition(LT, 2∼4$^{\circ}C$, 80% RH) was enough to preserve Potatoes for 11 months, but it was indicated to be limitations that the increase in reducig sugar as well as sprouting by about 3.3 to 6.7% occurred from the 3rd month of storage. Meanwhile, pit temperature(PT, 3∼15$^{\circ}C$, 75∼85% RH), room temperature(RT, 7∼17$^{\circ}C$, 80∼95% RH) and ambient temperature(AT, 2∼25$^{\circ}C$, 62∼72 RH) were shown infeasible conditions for the storage of potatoes mainly due to the increase In sprouting-rate and subsequent quality-loss after 3 months of storage. Based on the results, it proposed that more economical conditions, ranging 10 to 15$^{\circ}C$ and about 80% RH following sprout inhibition treatment should be used for the long-term storage of potatoes.

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A Study to Draw a Plan of Liquid Fertilizer Quality Certification Standards for Livestock Manure Management (가축분뇨의 관리를 위한 액비품질인증기준 방안도출 연구)

  • Jeon, Sang-Joon;Kim, Soo-Ryang;Hong, In-Gi;Kim, Ha-Je;Kim, Dong-Gyun;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.19 no.2
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    • pp.183-190
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    • 2013
  • Establishment of a new concept of environmental friendly livestock manure management is required based on the facts. But now liquid fertilizer quality in korea shows a large difference among regions and the regulations are uncertain. Focusing on precedent study on main level-grading factors of liquid fertilizer quality certification, the study collected laws and standards related to liquid fertilizer of livestock manure at home and abroad and produced evaluation standards. Liquid fertilizer was divided into four factors (fertilizing value, harmfulness, stability and uniformity). According to each item, scores were awarded based on 16 details: fertilizing value (Nitrogen concentration, the whole concentration of Nitrogen, Phosphoric acid and Kalium), harmfulness (heavy metals, pathogenic microorganism and antibiotics), stability (maturity degree and odour), uniformity (EC, BOD, SS, moisture content and salt). The grade of liquid fertilizer, A (42~48), B (34~41), C (26~33) were rated using total scores.

Basel III Effects on Bank Stability: Empirical Evidence from Emerging Countries

  • ASGHAR, Muhammad;RASHID, Abdul;ABBAS, Zaheer
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.3
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    • pp.347-354
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    • 2022
  • This article examines the influence of Basel III reforms, risk management, and banking sector efficiency on banks' financial stability in emerging countries. The data for this study is collected from various sources. Based on the GDP classification of IMF, the top 22 countries were selected as the sample. The sampling frame includes all six regions of the world including 482 banks and 3022 observations in total. The empirical analysis is carried out by estimating the random effects models. It is found that the effects of capital buffer, liquidity, and risk management practices are significant on financial stability. It is also noticed that the capital buffer has a constructive and significant influence on financial stability. However, liquidity management shows a mixed impact, as in some countries, its impact is positive and significant while, in other countries, it is insignificant. Risk management practices have an overall positive influence on financial stability in the case of large economies. However, results are insignificant in the case of small economies. Bank-specific variables, namely profitability, size, and efficiency have a positive whereas, loan quality has a negative impact on financial stability in the emerging countries. GDP has a positive impact on financial stability whereas inflation and unemployment both have a negative effect on financial stability.

A Study on Aircraft Flight Stability of T-50 Air Data Reconfiguration Mode (T-50 형상 재구성 모드의 항공기 비행 안정성에 관한 연구)

  • Kim, Chong-Sup;Hwang, Byung-Moom;Hwang, Min-Hwan;Bae, Myung-Whan
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.5
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    • pp.57-64
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    • 2005
  • Modern versions of supersonic jet fighter aircraft using digital flight-by-wire flight control system receive aircraft flight condition such as altitude, airspeed and AoA(angle of attack) from IMFP(Integrated Multi-Function Probe). IMFP sensors data have triplex structure using three IMFP sensors. An air data reconfiguration mode is applied to a T-50 flight control law to guarantee the aircraft flight stability when 2 or 3 IMFP sensors data are invalided. In this study, linear analysis and HQS(Handling Quality Simulator) pilot simulation are performed to analyze flight stability when the air data reconfiguration mode is applied to the control law. And we propose an example that the air data reconfiguration mode is applied to the control law due to second failure of IMFP during T-50 flight. It is found that the aircraft flight stability is not affected when the T-50 flight control law is changed to the air data reconfiguration mode.

Development of stability maps for flashing-induced instability in a passive containment cooling system for iPOWER

  • Lim, Sang Gyu;No, Hee Cheon;Lee, Sang Won;Kim, Han Gon;Cheon, Jong;Lee, Jae Min;Ohk, Seung Min
    • Nuclear Engineering and Technology
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    • v.52 no.1
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    • pp.37-50
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    • 2020
  • A passive containment cooling system (PCCS) has been developed as advanced safety feature for innovative power reactor (iPOWER). Passive systems are inherently less stable than active systems and the PCCS encountered the flashing-induced instability previously identified. The objective of this study is to develop stability maps for flashing-induced instability using MARS (Multi-dimensional Analysis of Reactor Safety) code. Firstly, we conducted a series of sensitivity analysis to see the effects of time step size, nodalization, and alternative MARS user options on the onset of flashing-induced instability. The riser nodalization strongly affects the prediction of flashing in a long riser of the PCCS, while time step size and alternative user options do not. Based on the sensitivity analysis, a standard input and an analysis methodology were set up to develop the stability maps of PCCS. We found out that the calculated equilibrium quality at the exit of the riser as a stability boundary above 5 kW/㎡ was approximately 1.2%, which was in good agreement with Furuya's results. However, in case of a very low heat flux condition, the onset of instability occurred at the lower equilibrium quality. In addition, it was confirmed that inlet throttling reduces the unstable region.

Modifications of a Grinding Machine Structure for the Improved Precision Machining (가공정도 향상을 위한 평면 연삭기의 설계 개선)

  • Shon, Jae-Yul;Ro, Seung-Hoon;Lim, Yo-Han;Lee, Jong-Hyung;Lee, Jae-Yul;Song, Eun-Seok;Lee, Tae-Hoon
    • Journal of the Korean Society of Industry Convergence
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    • v.12 no.2
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    • pp.99-105
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    • 2009
  • Among a few items with world wide competitiveness are the semiconductor and the LCD. Grinding/polishing is the most significant process in manufacturing semiconductor wafers and LCD panels, the most critical quality of which is the precision rate of the machined surfaces. It is well known that the control of the vibrations is the major factor in maintaining superb machined surfaces. In this paper the dynamic properties of a grinding machine have been investigated through the frequency analysis test and the computer simulation to deduce ideas of design modifications for improved stability. The alterations have been applied to the simulation model, which is supposed to have identical dynamic property with the original structure, to identify the effects and to finally achieve the satisfactory level of stability. The result shows that the machine can have much improved stability with relatively simple design changes, and also can improve the surface quality of the products.

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Enhanced oxidative stability of meat by including tannin-rich leaves of woody plants in goat diet

  • Garcia, Elisa Mariana;Lopez, Agustin;Zimerman, Maria;Hernandez, Olegario;Arroquy, Jose Ignacio;Nazareno, Monica Azucena
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.9
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    • pp.1439-1447
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    • 2019
  • Objective: The aim of this study was to evaluate the effect of dietary incorporation of tanninrich woody species on meat oxidative stability, carcass traits and meat quality in goats. Methods: Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat. Results: Feed intake, liveweight gain, carcass, and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups. Conclusion: The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.