• 제목/요약/키워드: Storage Stability

검색결과 1,876건 처리시간 0.029초

열안정성을 고려한 초소형 정보저장기기용 액추에이터 구조설계 (Structural design of small form factor swing arm type actuators with thermal stability)

  • 박철;유정훈;박노철;박영필;도야건;중촌자남
    • 정보저장시스템학회논문집
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    • 제2권3호
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    • pp.208-213
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    • 2006
  • The present state of the design of swing arm actuators for optical disc drives is to obtain the high efficient dynamic characteristics within a very compact volume. As a necessary consequence, the need of the small form factor (SFF) storage device has been arisen as major interests in the information storage technology. In this paper, we suggest the miniaturized swing arm type actuator that has high efficient dynamic characteristics for SFF optical disk drive (ODD). For the operating mechanism, it uses a tracking electromagnetic (EM) circuit for a focusing motion together. Moreover, due to the size constraint, the thermal stability of optical head is important. Therefore, the actuator is designed to emit the heat, which is generated by optical pick-up, along the actuator body easily. Initial model is designed based on the topology optimization method considering the thermal conductivity. Then, the structural parts of the actuator are modified to maintain the high sensitivity and to have wide control bandwidth by the design of experiments method (DOE) and new concept of decreasing mass and inertia. Finally, a swing arm type actuator for SFF ODD is suggested and its dynamic characteristics are verified.

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안정제 첨가와 저장온도에 따른 Salmon(Salno salar) Mince의 산화 안정성 (Oxidative Stability of Salmon (Salno salar) Mince as Affected by an Added Stabilizing Protein Ingredient and Storage Temperature)

  • 한명규
    • 한국식품영양학회지
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    • 제14권4호
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    • pp.300-304
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    • 2001
  • The oxidative stability of salmon mince to which milk protein concentrate(MPC) added was investigated. Salmon mince was stored at 4$\^{C}$ for 21 days, at -18$\^{C}$ for 20 days and at -18$\^{C}$ for 20 days after cooking in an electric omen. At each storage point, peroxide values(POV) were determined. Salmon mince with 4% MPC increased greater oxidative stability than control (without MPC). Sensory evaluation for measuring the oxidative stability of salmon mince was accomplished. Sensory scares of salmon mince with 4% MPC were higher than those of control. The results indicate that MPC could be useful for oxidative stability, as stabilizing protein ingredient of salmon mince.

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Development of W/O/W Multiple Emulsion Formulation Containing Burkholderia gladioli

  • KIM, HWA-JIN;CHO, YOUNG-HEE;BAE, EUN-KYUNG;SHIN, TAEK-SU;CHOI, SUNG-WON;CHOI, KEE-HYUN;PARK, JI-YONG
    • Journal of Microbiology and Biotechnology
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    • 제15권1호
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    • pp.29-34
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    • 2005
  • W/O/W (water-in-oil-in-water) type multiple emulsion was applied to improve the storage stability of an antagonistic microorganism, Burkholderia gladioli. Encapsulation of microorganism into a W/O/W emulsion was conducted by using a two-step emulsification method. W/O/W emulsion was prepared by the incorporation of B. gladioli into rapeseed oil and the addition of polyglycerin polyriconolate (PGPR) and castor oil polyoxyethylene (COG 25) as the primary and secondary emulsifier, respectively. Microcrystalline cellulose was used as an emulsion stabilizer. To evaluate the usefulness of W/O/W emulsion formulation as a microbial pesticide for controlling the bacterial wilt pathogen (Ralstonia solanacearum), the storage stability and antagonistic activity of emulsion formulation were tested in vitro. The storage stability test revealed that the viability of formulated cells in emulsion was higher than that of unformulated cells in culture broth. At $4^{\circ}C$, the viabilities of formulated cells and unformulated cells at the end of 20 weeks decreased to about 2 and 5 log cycles, respectively. At $37^{\circ}C$, the viability of formulated cells decreased to only 2 log cycles at the end of storage. On the other hand, the viable cells in culture broth were not detected after 13 weeks. In activity test, formulated cells in emulsion were more effective in inhibiting the growth of pathogen than unformulated cells in culture broth. Unformulated cells completely lost their antagonistic activity during storage under similar conditions. The W/O/W multiple emulsion formulation was shown to be useful as the novel liquid formulation for biological control.

조리냉동식품의 가공 및 저장 중 품질안정성 : (II) 정어리버어거의 동결저장 안정성 (Processing and quality stability of precooked frozen fish foods : (II) Quality stability of sardine burger)

  • 임치원;김진수;주동식;이응호
    • Applied Biological Chemistry
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    • 제35권4호
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    • pp.260-264
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    • 1992
  • 동결저장 중 정어리버어거의 pH는 약간 감소하였고, 휘발성 염기질소 함량은 조금 증가하였다. 동결저장 중 과산화물값, TBA값, 지방산조성 및 색조를 측정한 결과 항산화제를 첨가하여 정어리버어거를 제조한 제품(E)와 진공포장한 제품(V)이 지질산화나 산화변색이 억제되었고, 억제효과는 항산화제첨가제품(E) 보다 진공포장제품(V)이 더욱 우수하였다. 정어리버어거를 진공포장함으로써 histidine을 주체로 하는 유리아미노산, IMP를 주성분으로 하는 핵산관련물질, total creatinine, betaine, TMAO와 같은 정미성분, 구성아미노산 및 텍스튜어는 동결저장 중 거의 변화가 없었다.

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감마선 조사에 의한 미역의 저장성 개선 (Improvements in Storage Stability of Undaria pinnatifida after Gamma Irradiation)

  • 김현주;최종일;김재훈;전병수;안동현;김광훈;변명우;이주운
    • 한국식품저장유통학회지
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    • 제16권4호
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    • pp.590-593
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    • 2009
  • 감마선 조사가 미역의 저장성 개선에 미치는 영향을 평가하였다. 미생물 오염도 평가 결과 3 kGy 이하의 선량에서 미생물이 검출되지 않았다. 2주 저장한 후, 조사처리 하지 않은 미역의 미생물이 6 log CFU/g이 증가하였다. 그러나 5 kGy 조사 처리한 미역의 경우 미생물이 검출되지 않았다. 5 kGy의 감마선 조사를 적용하였을 때, 미역의 명도 값이 소폭 증가하였다. 미역의 경도 측정 결과 3 kGy 이하의 감마선 조사에 의해 영향을 미치지 않았으며, 저장기간에 따른 차이는 없는 것으로 나타났다. 이상의 결과를 종합하여 볼 때, 3 kGy 감마선 조사는 미역의 품질에 영향을 받지 않고, 저장성을 연장시킬 수 있는 효과적인 기술이라고 판단된다.

팜유와 우지로 제조한 라면의 저장 안정성에 대한 산화방지제 효과의 비교 (Relative Effectiveness of Some Antioxidants on Storage Stability of Instant Noodle(Ramyon) Fried by Palm Oil and Beef Tallow)

  • 양주홍;장영상;신효선
    • 한국식품과학회지
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    • 제20권4호
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    • pp.569-575
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    • 1988
  • 몇가지 산화방지제와 상승제를 첨가한 팜유와 우지로 튀긴 라면의 저장 안정에 대한 산화방지 효과를 저장 라면에서 추출한 유지의 이화학적 항수(과산화물값, carbonyl값, conjugated diene)의 변화와 n-hexanal의 생성량을 측정하여 비교하였다. 팜유와 우지에 ${\delta}-Toc$을 첨가한 것이 $DL-{\alpha}-Toc$을 첨가한 것보다 저장 안정성이 다같이 우수하였고고 ${\delta}-Toc$$DL-{\alpha}-Toc$에 상승제로 ascorbyl palmitate를 첨가하였을 때가 citric acid를 첨가하였을 때 보다 상승효과가 좋았다. 우지에서는 페놀계 산화방지제를 첨가한 것이 tocopherol류를 첨가한 것보다 저장 안정성이 우수하였으나 팜유에서는 BHA와 BHT 혼합제를 첨가한 것이 ${\delta}-Toc$를 첨가한 것보다 저장 안정성이 좋지 못하였다. 저장 라면에서 추출한 유지의 과산화물값, carbonyl값 및 conjugated diene산의 변화는 서로 잘 일치하지 않았다. 그러나 저장라면에 대한 산화방지 효과는 저장 라면중의 hexanal의 농도와 밀접한 관계가 있었다.

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액체연료탱크의 슬로싱 거동 평가기법 (Evaluation for Sloshing Behaviors of Liquid Storage Tank)

  • 윤성호;박기진;심국상
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.314-317
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    • 2002
  • The sloshing phenomenon sometimes happens to be occurred in the liquid storage tank due to the unexpected and/or inevitable vibrating conditions and may result in severe effects on the structural stability. This study deals with the development of experimental techniques for the evaluation of sloshing behavior in the liquid storage tank and for the identification of natural frequencies and mode shapes by varying with various vibrating conditions. In addition, suitable method is suggested to minimize the sloshing effect on the liquid storage tank and its validity is experimentally investigate d.

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유연체 회전축 모델을 이용한 자기부상형 플라이휠 에너지 저장장치의 제어시스템 안정성 및 성능 해석 (Analysis of Control Stability and Performance of Magnetically-Levitated Flywheel Energy Storage System using Flexible Rotor Model)

  • 유승열;이욱륜;배용채;노명규
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 추계학술대회 논문집
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    • pp.258-263
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    • 2009
  • This paper describes an analysis of the stability and performance of a large-capacity flywheel energy storage system (FESS) supported by active magnetic bearings. We designed and manufactured the system that can store up to 5kWh of usable energy at the maximum speed of 18,000 rpm. In order to analyze the stability of the systems accurately, we derived a rigid body rotor model, flexible rotor model using finite-element method, and a reduced-order model using modal truncation. The rotor model is combined with those of active magnetic bearings, amplifiers, and position sensors, resulting in a system simulation model. This simulation model is validated against experimental measurements. The stability of the system is checked from the pole locations of the closed-loop transfer functions. We also investigated the sensitivity function to quantify the robustness of the systems to the disturbances such as mass imbalance and sensor noises.

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잣 지방질의 산화 안정성에 관한 연구 (Studies on the Oxidative Stability of Pinenut Oil)

  • 김명;이숙희;유정희;최홍식
    • 한국식품과학회지
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    • 제20권6호
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    • pp.868-872
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    • 1988
  • 잣을 저장조건을 달리하여 산화양상을 살펴보고 이어 정제단계별로 산화양상에 따른 변화를 살펴보았다. 잣을 $35^{\circ}C$에서 10주간 저장하면서 함유지방질의 산화양상을 살펴본 결과 잣 알갱이 상태는 조직을 마쇄하더라도 지방질로 추출한 상태보다 대단히 높은 산화안정성을 나타내었다. 또한 조지방질은 정제단계를 거칠수록 그 산화안정성이 감소되었으며 정제지방질, 탈검 및 탈산된 지방질, 탈검 탈산 및 탈색된 지방질, 탈검된 지방질, 조지방질 순으로 산화 안정성이 높아졌다. 이것은 정제단계에서 제거된 물질들이 산화 안정성을 증가시키는 요인으로 작용하는 것으로 여겨진다.

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Salmonella thphi Ty21a의 동결 건조와 안정성 (The lyophilization and stability of Salmonella typhi Ty21a)

  • 김세란;박동우;전홍렬;김희준;한성순;김기호;김홍진
    • 약학회지
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    • 제43권6호
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    • pp.793-797
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    • 1999
  • Salmonella typhi Ty21a is an attenuated strain of S. typhimurium and used for oral typhoid vaccine. In an attempt to increase the stability of Ty21a manufacturing typhoid vaccine, we studied about the stability of freeze-dried Th21a including additives at various temperature conditions. In order to investigate the freeze-drying rate of Ty21a according to various absorbance, we lyophilized Ty21a by using 8% sucrose as a stabilizer. The optimal freeze-drying rate of Ty21a was appeared when OD (optical density) value of the growth was between 2.5 and 3.0. To investigate the stability of Ty21a at various temperature, the viability was measured after storaging the freeze-dried Ty21a at the room temperature, cold and freezing condition for 1 week. The viability of Ty21a in cold and freezing storage condition was 5 times more stable than in room temperature. To search the most stable additives for the freeze-dried Ty21a, the viability of Ty21a including additives at the various storage condition was estimated. Mannitol and loctose were the most stable additives. Theses results suggest that the OD value of Ty21a growth, low temperature, mannitol and lactose are important factors for the optimal freeze-drying rate, the stable storage and the most stable additives, respectively.

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