• 한국운동역학회지
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• 제20권3호
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• pp.261-266
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• 2010

Human body is hard to be in perfect balance during walking. Most of time the trunk is supported by one leg and the center of mass(COM) falls to the contralateral side. Thus, dynamic variables such as the velocity of the COM should be considered when gait stability is evaluated. The purpose of this study was to investigate whether the extrapolated center of mass(XCom) which utilized the COM position and its velocity, is appropriate to evaluate gait stability. Ten healthy adults participated in this study and performed 3 different types of gaits(normal(NG), hands on waists(HWG), and hands on shoulders(HSG)) onto 4 different types of obstacle(obstacle height: 0%, 30%, 40% and 50% of leg length). Medio-lateral Com-CoP and XCom-CoP inclination angle were calculated during support phase. For all condition, greater M-L XCoM-CoP inclination angles were found(p<.05) compared with those of matched obstacle height CoM-CoP. Especially, M-L XCoM-CoP inclination angle at 50% height revealed the best condition for monitoring dynamic stability. Significantly increased in M-L XCoM-CoP inclination angle was found(p<.05) as obstacle height increased on NG and HWG.

• 한국식품조리과학회지
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• 제6권3호통권12호
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• pp.9-15
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• 1990

Peanut prptein isolate was tested for the purpose of finding out the effect of pH, Sodium Chloride concentration and heat treatment on the solubility, surface hydrophobicity, foam expansion and foam stability. The solubility of peanut protein isolate was affected by pH and showed the lowest value at pH 4.5. When the peanut protein isolate was heated, the solubility decreased at pH 3 and pH 7 but at pH 9 solubility increased. At all pH range, solubility decreased as NaCl was added. The surface hydrophobicity of peanut protein isolate showed the highest value at pH 1.5. Generally, at acidic pH range the surface hydrophobicity was high, but at alkaline region, the surface hydrophobicity increased as the temperature increased. And when NaCl was added, the surface hydrophobicity was also increased. Foam expansion of peanut protein isolate was no significant difference among the values about pH. When the peanut protein was heated and NaCl was added, foam expansion was increased at pH 7. Foam stability was significantly low at pH 4.5 and foam stability was increased at acidic pH region below pH 4.5. At pH 7 and pH 9, heat treatment above $60^{\circ}C$ increased foam stability. When NaCl was added, foam stability was significantly increased at pH 3 and pH 7.

• 호남수학학술지
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• 제33권4호
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• pp.467-485
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• 2011

We consider the Hyers-Ulam-Rassias stability problem $${\parallel}u{\circ}A-{\upsilon}{\circ}P_1-w{\circ}P_2{\parallel}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$$ for the Schwartz distributions u, ${\upsilon}$, w, which is a distributional version of the Pexider generalization of the Hyers-Ulam-Rassias stability problem ${\mid}(x+y)-g(x)-h(y){\mid}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$, x, $y{\in}\mathbb{R}^n$, for the functions f, g, h : $\mathbb{R}^n{\rightarrow}\mathbb{C}$.

• 미생물학회지
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• 제13권2호
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• pp.59-63
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• 1975

When the enzyme preparations were at various temperatures for 1 hour, the thermal stability for the enzyme was maximum at $30{\circ}C.$ The optimum temperature for the enzyme activity was at $40{\circ}C.$ When the enzyme preparations were exposed to various pHs for 22 hours, the enzyme stability was maximum at pH 3.8, and it was decreased gradually as the pH rose up to 4.8, above which the stability was greatly restored. When the exposure period was extended from 22 to pH's 3.0 and 5.9, but the stability tended to rise at pH's below 3.0 and above 5.9. The optimum pH for the enzyme activity was obtained at 4.8.

• 대한수학회논문집
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• 제26권2호
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• pp.261-271
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• 2011

We consider the Hyers-Ulam-Rassias stability problem ${\parallel}2u{\circ}\frac{A}{2}-u{\circ}P_1-u{\circ}P_2{\parallel}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$, $x,y{\in}{\mathbb{R}}^n$ for the Schwartz distributions u, which is a distributional version of the Hyers-Ulam-Rassias stability problem of the Jensen functional equation ${\mid}2f(\frac{x+y}{2})-f(x)-F(y){\mid}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$, $x,y{\in}{\mathbb{R}}^n$ for the function f : ${\mathbb{R}}^n{\rightarrow}{\mathbb{C}}$.

• 분석과학
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• 제8권3호
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• pp.293-298
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• 1995

수용액에서 pH와 일정공급전위 변화에 따른 강철심에 도금된 놋쇠의 안정성을 교류 임피던스로 측정하여 연구하였다. 일정 pH에서 일정공급전위가 양전위로 감에 따라 코팅기공저항은 감소된다. 그 사실은 일정공급전위가 양전위로 감에 따라 도금된 놋쇠층이 용액에 더 용해됨을 나타낸다. 강철심에 도금된 놋쇠의 안정성은 pH=7.1 > pH=4.0 > pH=10.0 순으로 감소한다. 위와 같은 실험결과는 전자현미경 (SEM)/에너지분산분광계(EDS)의 자료에 의해 증명된다.

• 한국콘텐츠학회논문지
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• 제9권12호
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• pp.348-356
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• 2009

본 연구는 요부안정화에 도움이 되는 불안정 기저면의 운동인 공운동, 전신진동운동, 매트운동을 선택하여 각 운동조건의 체간과 하지의 근 활성도(%RVC)를 비교한 결과, 배속빗근은 전신진동기조건에서 매트조건보다 유의하게 증가하였고(p<.05), 넙다리곧은근과 장딴지안쪽갈래근은 공과 전신진동기조건에서 매트조건 보다 유의하게 증가하였으며(p<.05), 오금안쪽갈래근은 공조건에서 매트조건 보다 유의하게 증가하였다(p<.05). 세 가지 운동방법으로 4주간 안정화운동프로그램을 진행시킨 결과, 세 운동군 모두 운동전보다 운동 후에 각 방향에서 안정성한계의 유의한 증가가 있었다(p<.05). 각 운동군의 운동 전 후의 안정성한계의 차이 값을 비교한 결과, 각 운동군에서 네 방향(전 후 좌 우)의 안정성한계에 유의한 차이가 없었다(p>.05). 따라서 교각자세에서의 요부안정화 운동방법 중에서 체간근과 하지근육의 근활성도는 공과 전신진동기 운동에서 더 증가되었지만, 안정화운동 4주후에는 세 운동 모두 자세안정성을 증진시키는 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제1권1호
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• pp.101-108
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• 1971

The stability and toxicity test for p.p'-DDT, DDVP and dipterex that put to used sample in this study effects is follows A. about p.p'-DDT (1) In elevating the stability of p.p'-DDT, best stabilizing solvent was benzene. (2) The stability-agent has no difficulty as long as it not contain metal ion for instance $Z_n^{2+}$,$C_r^{3+}$,$Al^{3+}$,and $Fe^{2+or3+}$ but in case of contain $F_e^{3+}$, the combination of salicylaminoguanidine is best effective. (3) Using this product for water-suspension, We must use span 40 for stability agent and adding it at the same time. (4) We must use container which does not week alkali and metal ion but it is to preserved in tight light-resistant container. (5) The stopper of container is adapted with above-mentioned condition of container, but it is better not to use metal material. (6) This product needs opening ventilation more than 30 minutes after diffusion or spray and in the room we remove cause of remained poison by cleaning the bottom. B. about DDVP and Dipterex (1) Benzene or toluene in best solvent to preserve stability of DDVP and Dipterex. (2) Span 40 is superior for stability agent of this product and second is span 80. (3) The pH of solution is very stable in pH 5-6 and comparative stable in alkali more than p,p'-DDT. (4) Container is to preserved in tight, lightresistant container and especially be careful of outflow and inflow of water. (5) Because this product is centeral stimulant poison, we must pay attention to prevent cause of contact diadermic toxicity after use.

• 한국식품저장유통학회지
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• 제4권3호
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• pp.331-335
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• 1997

The stability of carotenoid pigments extracted from Chrysanthemum petals against pH, sugar, and organic acid was investigated. The contents of total carotenoids in C. boreale and C. morifolium were 3.37mg% and 4.56mg% Per fresh weight, respectively. The elect of pH on the stability of extracted carotenoids showed that the periods reaching 50% of pigment retention were more than 5 to 6 days in pH 4, and the longer periods in pH 6 to 7 in both samples. The addition of sugars such as sucrose, sorbitol, glucose and fructose resulted in the reduction in pigment stability of C. boreale, but C. morifolium was contrast to C. boreale. However, citric acid and ascorbic acid were found to have a protective effect on both carotenoid samples extracted from C. boreale and C. morifolium.

• 한국식품위생안전성학회지
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• 제12권1호
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• pp.15-19
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• 1997

The stability of monascin yellow pigment isolated from Monascus purpureus was determined over a period of storage for the wide range of pH, various metal ions and antioxidants. The absorption maximum of monascin pigment was 385 nm. Monascin pigment was more stable in acid solutions than in alkaline (pH 9 and pH 11) during storage period. It was also observed the reduction of absorption was occur after 3 days storage. The stability of monascin pigment was not changed by adding the various metal ions of the concentration of 10-4 M, however, it was unstable by adding the Zn2+, Al3+ and Fe3+ of 103- M concentration. The antioxidants. BHA, BHT, cysteine and L-ascorbic acid, have no effects on the stability of monascin yellow pigment. Thus, it may be concluded that the monascin pigment is stable and useful food additives as the natural colorant except for the alkaline food and food containing the Zn2+, Al3+ and Fe3+.