• 멤브레인
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• 제6권2호
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• pp.79-85
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• 1996

본 연구는 소수성 고분자재료인 PSf와 양이온성화된 AMPS막을 제조하여 이의 투과특성에 관하여 조사하였다. AMPS분리막은 소수성인 PSf막에 비하여 fouling이 감소하였다. 특히, AMPS막은 양이온성을 띠고 있어 염기성 염료, 단백질, 아미노산과 같이 막표면과 동일한 전하를 가지고 있는 용질을 효과적으로 분리할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.715-720
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• 2002

Kinetic studies of the reaction of Z-aryl cyclobutanecarboxylates with X-pyridines in acetonitrile at $55.0^{\circ}C$ have been carried out. The reaction proceeds by a stepwise mechanism in which the rate-determining step is the breakdown of the zwitterion ic tetrahedral intermediate, T $\pm$ . These mechanistic conclusions are drawn based on (i) the large magnitude of ${\rho}X$ and $\rhoZ$, (ⅱ) the positive sign of ${\rho}XZ$ and the larger magnitude of $\rhoXZ$ than normal SN2 processes, (ⅲ) a small positive enthalpy of activation, ${\Delta}H{\neq}$, and a large negative, ${\Delta}S{\neq}$, and lastly (iv) adherence to the reactivity-selectivity principle (RSP) in all cases.

• 천문학회보
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• 제36권2호
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• pp.84.1-84.1
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• 2011

In this study, we intend to inquire of how the temporal variation and spatial distribution of magnetic helicity injection in a CME-producing solar active region are related to the CME occurrence. We therefore investigate long-term (a few days) variation of magnetic helicity injection in the active region NOAA 9236 which produced multiple CME events. As a result, it is found that a noticeable increase in helicity of negative sign was first made for the first ~1.5 days and then 6 CMEs occurred while the relatively more injection of oppositely signed (positive) helicity was taking place for the next ~2 days. Afterwards, 2 CMEs in the region occurred while a more negative helicity is being injected again compared to a positive helicity. In addition, from helicity flux density maps, we found that the CMEs originated from this active region seem to be involved with the interaction of two magnetic field systems characterized by opposite signs of helicity.

• 대한기관식도과학회지
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• 제5권1호
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• pp.22-29
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• 1999

Background： Infectious mononucleosis is a disease precipitated by Epstein-Barr virus(EBV) in mostly children, some seronegative adolescents and young adults comprising clinical symptoms such as fever, lymphadenopathy, and pharyngitis as well as laboratory findings such as hetero-phil antibodies and atypical lymphocytosis. It is confirmed by serologic test for EBV. Materials and Methods： A retrospective evaluation of 26 patients who diagnosed with infectious mononucleosis was peformed through the analysis of typical symptom, sign and laboratory findings. Results : Infectious mononucleosis occurs mostly at 3 to 10 years (74.9%), common symptoms and signs are fever, cervical lymphadenopathy, tonsillar enlargement and exudate. Positive ratio of atypical Lymphocyte(>10%) and hetrophil antibodies are 61.5%, 35.2% respectively, it is less diagnostic. EBV-viral capsid antigen(VCA) IgM are positive in all cases, so it is most diagnostic findings. Conclusion： Infectious mononucleosis should be considered as a cause of cervical lymphadenopathy and pharyngotonsillitis in children and young adults, the assessment of EBV-VCA IgM is necessary for the diagnosis.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.925-930
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• 2003

Kinetic studies of the reaction of Z-aryl cyclopropanecarboxylates with X-pyridines in acetonitrile at 55.0 ℃ have been carried out. The reaction proceeds by a stepwise mechanism in which the rate-determining step is the breakdown of the zwitterionic tetrahedral intermediate, $T^{\pm}$. These mechanistic conclusions are drawn base on (i) the large magnitude of ρx and ρz, (ii) the positive sign of ρxz and the larger magnitude of ρxz than normal $S_N2$ processes, (iii) a small positive enthalpy of activation, Δ$H^≠$, and a large negative, Δ$S^≠$, and lastly (iv) adherence to the reactivity-selectivity principle (RSP) in all cases.

• Kyungpook Mathematical Journal
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• 제64권1호
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• pp.113-131
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• 2024

In this paper we give conditions for the existence of, and describe the asymtotic behavior of, radial positive solutions of the nonlinear elliptic equation of Emden-Fowler type with convection term ∆_p u + 𝛼|u|^q-1u + 𝛽x.∇(|u|^q-1u) = 0 for x ∈ ℝ^N, where p > 2, q > 1, N ≥ 1, 𝛼 > 0, 𝛽 > 0 and ∆_p is the p-Laplacian operator. In particular, we determine ${\lim}_{r{\rightarrow}}{\infty}\,r^{\frac{p}{q+1-p}}\,u(r)$ when $\frac{{\alpha}}{{\beta}}$ > N > p and $q\,{\geq}\,{\frac{N(p-1)+p}{N-p}}$.

• Journal of Acupuncture Research
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• 제35권1호
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• pp.4-10
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• 2018

The aim of this report was to show the effects of acupotomy in patients with carpal tunnel syndrome. Four patients were treated with acupotomy twice. Visual analogue scale (VAS), Tinel's sign, Phalen's test, Boston carpal tunnel syndrome questionnaire (BCTQ), muscular strength test, and a cross-sectional area of median nerve was measured using ultrasound before and after treatment. In all 4 cases, the VAS score, BCTQ score and cross-sectional area of median nerve, all decreased and muscular strength test score increased. Tinel's sign and the Phalen's test changed from a positive to a negative in most cases. This report shows that acupotomy is an effective treatment for carpal tunnel syndrome. Further larger are needed to fully evaluate the beneficial effects of this treatment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2718-2720
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• 2002

The algorithm that can estimate frequency in real-time by using the resampling of a signal which was known frequency band like biological signals, was suggested in this study. A sinusoid signal is simulated as a practical measured signal. The sinusoid signal is sampled by using the impulse-train, and is subtracted the backward sample from forward by the sampled signals. The continuous sign, such as positive, negative or zero is counted from the calculation result of the subtraction, and those is stored. Therefore, the measured frequency is estimated by using the magnitude of continuous sign and the sampling period. The algorithm designed in this study is proven through the computer simulation.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.851-855
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• 2008

The reactions of O,O-diphenyl Z-S-phenyl phosphorothiolates with X-pyridines have been studied kinetically in acetonitrile at $35.0{^{\circ}C}$. The Hammett plots for substituent (Z) variations in the leaving group (log $k_2$ vs. $\sigma$ Z) are biphasic concave downwards with breaks at Z = H. The large magnitudes of ${\rho}X(\rho_{nuc})$, ${\beta}X(\rho_{nuc})$, and the cross-interaction constant, $\rho$XZ, suggest frontside nucleophilic attack toward the leaving group. The sign reversal of $\rho$Z from positive in $\sigma$ Z $\leq$ 0 to negative in $\sigma$ Z $\geq$ 0 is interpreted as the change in mechanism from concerted to stepwise with rate-limiting expulsion of the leaving group. The anomalous negative sign of $\rho$ Z for leaving groups with electron-withdrawing substituents is interpreted as the intramolecular ligand exchange process of the leaving group from the equatorial position in the intermediate to the apical position in the TS.

• 한국사회복지학
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• 제45권
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• pp.315-340
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• 2001

The purpose of study is to examine the effects of family support on the life satisfaction of elderly with disabilities and provide a ground necessary to improve it. Research was conducted on 167 elderly with hearing, visual and physical disabilities aged over 60 who were living in Seoul and Pusan. Telephone survey, sign language and interview, in accordance with types of disability, were adopted to collect data effectively. That is telephone survey was used for elderly with visual impairment whereas face-to-face interview for physical impairment and sign language for hearing impairment by volunteers. Collected data were analyzed, using hierarchical regression analysis. This study utilized two different models, direct effect model and buffering effect of social support in order to examine the effects of familial support on the life satisfaction of elderly with disabilities. Research findings suggest that the level of life satisfaction appeared to be low in general among elderly with disabilities and emotional family support exerted a positive effect on life satisfaction. In addition, it is empirically supported that emotional family support buffered the negative effect of economic limitations on life satisfaction. In other words, the effects of economic limitations as stress factor decreased with the increase in the frequency of emotional support, however, the level of life satisfaction decreased at a mercy of the stress factor of economic limitations with the decrease in the frequency of emotional support. Finally, this paper attempted to provide some alternatives to effectively improve life satisfaction among elderly with disabilities based on empirical findings.