• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.1-11
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• 2000

Relining and rebasing are essential for long-term success and oral health in removable prosthodontics. Major features of failures between metal base and relining resins are adhesive failure due to lack of chemical bonding. The purpose of this study was to find a better metal primer and metal surface treatment method that enhance the bonding strength with relining resin materials. The surfaces of ticonium alloys were treated with $25{\mu}m$ sandblasting (Group A), stone wheel(Group B), stone wheel and EZ oxisor(Group C), $75{\mu}m$ sandblasting(Group D) and EZ oxisor application after $75{\mu}m$ sandblasting(Group E). They were subdivided into no primer application (Group I), MR bond application(Group II) and Metafast bonding liner (Group III). Then specimens were completed though being bonded with relining resins. The specimens were stored in $38^{\circ}C$ water for 48 hours and tensile strength was measured using the universal testing machine. The results were as follows, 1. Primer application groups showed higher bond strength than no primer application group(p<0.05). 2. In comparison with primer application groups, MR bond group showed higher bond strength than Meta fast bonding liner application group(p<0.05). 3. In comparison with surface treatment methods, Bond strengths of group A and B were significantly different with group C, D, and E, and group C were significantly different with group D, and E in no primer application group()(0.05). In primer application groups, group A, B, C were significantly different with group D and E(p<0.05). According to results of this study, Metal primer application and metal surface roughening were considered to be advantageous for relining of metal base dentures.

• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.597-606
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• 1998

The purpose of this study was to evaluate the shear bond strength of the Compoglass Carvifil bonded on the dentin surface according to etching or non-etching and two time application or three time application of single component. Human non-carious 60 extracted 3rd molar were used. The occlusal dentin surfaces of all teeth were exposed with Diamond Wheel Saw and polished with Lapping & Polishing machine(South Bay Technology Co., U.S.A). The teeth were then distributed randomly into four groups of 15 teeth each and dentin surface were conditioned as following. Control group : Non-etching, two times application of Syntac Single Component. (According to manufacture's instruction) Experimental group 1 : Non-etching, three times application of Syntac Single Component. Experimental group : 2 Etching, two times application of Syntac Single Component. Experimental group 3 : Etching, three times application of Syntac Single Component. Compoglass were bonded to exposed dentin surfaces and all samples were placed in distilled water for 7 days. The shear bond strengths were measured by universal testing machine (SHIMADAZU AUTOGRAPH, AGS-4D., Japan). The results were as follows : 1. Experimental group 3 revealed the highest value (30.75${\pm}$4.74 MPa) and control group revealed the lowest value(14.85${\pm}$2.69 MPa). There was significant difference of shear bond strength among four groups(P<0.01) 2. The acid-etching groups (experimental group 2, 3) had higher shear bond strengths than non etching groups(control group and experimental group 1). 3. The additional application of Syntac single component groups revealed a higher bond strength than two times application groups (control group and experimental group 2).

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.27 no.1
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• pp.1-16
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• 2014

Objectives : The aim of this study is to examine the effect of external application containing herbal extracts (Betula platyphyllae Cortex, Viticis Fructus, Agrimoniae herba) to patients with atopic dermatitis. Methods : Twenty patients (experiment group) were treated with the external application containing herbal extracts (Betula platyphyllae Cortex, Viticis Fructus, Agrimoniae herba) and other twenty patients (control group) were treated with normal external application that doesn't contain herbal extracts for 2weeks. We observed comparisons between experiment and control group after 1week, 2weeks. Degrees of severity of atopic dermatitis were measured by SCORAD index (Scoring of Atopic Dermatitis Index). Statistical significance was achieved if the probability was less than 5% (p<0.05). Results : 1. After 1week of external application treatment, SCORAD Index in experiment group was significantly decreased comparing with control group, which is a marginally significant result between two groups. But after 2weeks the experiment group showed no statistically significant result. 2. After 1week of external application treatment, Intensity Criteria (Erythema, Edema/papulation, Total) in experiment group was significantly decreased comparing with control group, which is a statistically significant result between two groups. But after 2weeks the experiment group showed no statistically significant result. 3. After 1week and 2weeks of external application treatment, comparison of changes in Subjective Symptoms (Pruritus, Insomnia) indicated that the experiment group showed no statistically significant result. 4. After 1week of external application treatment, Total Quality of life through Skindex-29 in experiment group was significantly decreased comparing with control group, which is a marginally significant result between two groups. But after 2weeks the experiment group showed no statistically significant result. Conclusions : As a result of applying the external application containing herbal extracts to patients with atopic dermatitis and watching the progress, we can speculate that the external application containing herbal extracts has especially short-term therapeutical effects in mitigating the symptoms of Atopic Dermatitis. Thus, it is concluded and considered that the external application containing herbal extracts can be used by atopic patients effectively with almost no side-effect.

• Journal of Korean Elementary Science Education
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• v.30 no.4
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• pp.601-614
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• 2011

The purpose of this study was to investigate significant differences between the application group and nonapplication group of integrated science education in the science class about elementary teachers' perceptions and PCK. The results are as follows. First, no significant differences were found about science teachers' fundamental background variables between the two groups. This results showed that the application of integrated science education didn't have relation with the fundamental background variables. It was found that the application group of integrated science education has a lower frequency than the application group, however, it has been analysed that the application group has been applied at the introduction stage for students' motivation, focused on biology as twice every month. Second, to apply a successful integrated education in the elementary science class, it has analysed that not only teachers should need to understand about application method and concept of integrated science education but also science textbook and teaching-learning material should be developed and diffused in the well-integrated science. Third, it was found that professionality of elementary teachers to teach the scientific content knowledge is not comparatively high and non-application group of integrated science education has a lower PCK than the application group. Therefore, it should be provided that not only training programmes to learn interdisciplinary knowledge related to science, can lead to more understanding about instructional design, teaching strategies and concept for integrated science education should be developed but also chances to participate in various training programmes should be provided to enhance elementary teachers' professionality for integrated science education.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.523-531
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• 2000

The purpose of this study was to investigate the Effect of stimulus in the Acupuncture point with Ultrasound and Electro-acupuncture on human's Cholinesterase activity. Pain is physiological symptoms in human body. Pain stimulation transference is according to Acetylcholine that is a matter of nerve stimulation. Cholinesterase analyze the Acetylcholine and Cholin acetylase compose the Acetylcholine. To identify of Cholinesterase activity, this study attempted to Electroacupuncture and Ultrasound for 20 person. Twenty subjects participating in this consisted of A group(difference of Cholinesterase's figure make use of Electroacupuncture with Zi-Shil), B group(difference of Cholinesterase's figure make use of Ultrasound with Zi-shil), C group(difference of Cholinesterase's figure make use of Eltroacupuncture and Ultrasound with Zi-shil). As a result the following conclusion was draun: 1. A group showed significantly decreased of Cholinesterase's figure make used of Electroacupuncture with Zi-Shil(the period is between pre-application and 20minute after application, between pre-application and mean of 20minute-30minute after application). 2. B group showed significantly decreased of Cholinesterase's figure make used of Ultrasound with Zi-Shil(the period is between pre-application and 3minute after application, between 3minute after application and 7minute after application, between preapplication and 7minute after application, between pre application and mean of 3minute-7minute after application). 3. C group not showed significantly decreased of Cholinesterase's figure make used of Elcetroacupuncture and Ultrasound with Zi-Shil(the period is between pre-application, between 20minute-Eletroacupuncture and 3minute-Ultrasound after application, between 30minute-Eletroacupuncture and 7minute-Ultrasound after application). The results of this study showed that decrease of Cholinestese' s figure make used of Elctroacupuncture and Ultrasound Zi-Shil. The result mean stimulation of Elctroacupuncture and Ultrasound decreased Acetylcholin' quantity. And decrease of Acetylcholin' quantity decreased Cholinesterase' figure.

• Journal of Korean society of Dental Hygiene
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• v.1 no.1
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• pp.125-132
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• 2001

This study was carried out to investigate the effect of multi or single application of fluoride plus 0.05% NaF solution on the remineralization of dental caries lesion. The microhardness changes of enamel surface were measured after application of fluoride and precipitation of 0.05% NaF solution on 6 groups of cow's tooth on which the artificial carious lesions were formed first. Test groups were calssified into two step application with NaF, $SnF_2$ and APF under different application time conditions plus 0.05% NaF solution(group I, II, III, IV) and single application with APF plus 0.05% NaF solution (group V) and control(0.05% NaF solution only, group IV). The obtained results were as follows. 1. Regarding microhardness change of enamel surface. microhardness increments in group I(NaF for 1 minute+APF for 3 minutes+0.05% NaF solution for 1 minute), II($SnF_2$ 1 min+APF 3 min+NaF sol.), III($SnF_2$ 2 min+APF 2 min+NaF sol.), IV(NaF 2 min+APF 2 min+NaF sol.) and V(APF 4 min+NaF sol.) were significantly greater than group VI.(P<0.05) 2. Microhardness changes of shorter application time of $SnF_2$ (group II) were significantly greater than group III. (P<0.05) 3. Microhardness changes were variable with kinds of fluoride, application sequence and application time of fluoride. but had no relation with the number of fluoride application.

• Biomedical Science Letters
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• v.16 no.2
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• pp.113-118
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• 2010

The purpose of this study was to investigate the effects of angular velocity on muscle strength and blood constituent. Subjects was classified into two groups, which were $60^{\circ}/sec$ angular velocity group (n=8), and $240^{\circ}/sec$ angular velocity group (n=8). Each group was applied to perform the isokinetic exercises on extensor muscle group for each 7 times in 10 set (3 days per a week for 3 weeks). Muscle strength was measured using peak torque of quadriceps femoris and blood constituent was measured using RBC, WBC and Hb. The peak torque was more significantly increased after 3 weeks application of $60^{\circ}/sec$ angular velocity group than $240^{\circ}/sec$ angular velocity group. The RBC and Hb were more significantly increased after 3 weeks application of $60^{\circ}/sec$ angular velocity group than $240^{\circ}/sec$ angular velocity group. But WBC was more significantly increased after 3 weeks application of $240^{\circ}/sec$ angular velocity group than $60^{\circ}/sec$ angular velocity group. These results indicate that $60^{\circ}/sec$ angular velocity isokinetic exercise application were effective treatment strategy on increase of muscle strength. But $240^{\circ}/sec$ angular velocity isokinetic exercise application were effective treatment strategy on immune protect system.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.10-19
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• 2008

Objective : To investigate the effects of Radix Ophiopogon japonieus on atopic dermatitis, I prepared DNCB(2,4-dinitrochlorobenzen) induced atopic dermatitis NC/Nga mice and observed the mice by four ways; eye observation, the number of skin behavior times, histological changes of skin and cytokine(Total IgE, IL-4, $IFN-{\gamma}$). Methods : After prepare Radix Ophiopogon japonicus extract, DNCB induced atopic dermatitis NC/Nga mice were divided into three groups. The first is Control group which was intact group. The second is Medication group which was orally medicated Radix Ophiopogon japonicus extract one time a day for consecutive 5 days. The third group is Application group which was applied Radix Ophiopogon japonicus extract externally one time a day for consecutive 5 days. After that, the effect of Radix Ophiopogon japonicus on atopic dermatitis was observed. Statistical analysis was performed by using Kmskal-Wallis test and statistical significance was set at less than 5%. Results : 1. Radix Ophiopogon japonicus showed some in both Medication group and Application At observation of skin morphologic change, effects to prevent erythema reaction on skin group. 2. At the number of scratching behavior times, Radix Ophiopogon japonicus showed an effect to decrease scratching behavior times, but there was no statistical significance among three groups. 3. At skin tissue H-E stain, Radix Ophiopogon japonicus showed an effect to prevent skin epidermal tissue damages and also showed that it could keep the skin healthy in both Medication group and Application group. Especially in Application group, the skin of mouse showed almost normal recovery. 4. At cytokines, there was no statistical significance among three groups in IgE and IL-4. But Radix Ophiopogon japonicus showed an significant effect to suppress $IFN-{\gamma}$ in both Medication group and Application group. There was no significant difference between two groups. Conclusion : Radix Ophiopogon japonicus has some effects on atopic dermatitis in both internal medication and external application.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2611-2613
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• 2002

본 논문에서는 전력선 통신 채널의 간접 잡음 측정에 대한 연구를 하였다. 주위 환경에 의한 Noise 및 여러 통신매체에 의한 방해전파에 의해 전력선 통신 채널은 송신 측의 고출력 요구와 가능한 전력선 통신의 대역폭이 감소하는 악화된 통신환경을 보여 준다. 이러한 Noise를 측정하는 방법은 Coupling Capacitor를 이용한 직접 측정 방식과 이동 측정 장치를 이용한 간접 측정 방식이 있다. 전자는 광범위한 측정지역과 측정장비의 설치 등에서의 번잡함으로 효과적인 Noise 측정이 어렵다. 본 논문에서는 두 가지 방식의 Noise 측정 결과의 비교 및 검토를 통해 이동 측정 장치를 이용한 방식의 장점과 보완할 점을 검토였으며, 특히 직접 측정 방식과의 결과 값의 차이를 보상할 수 있는 상관관계 분석의 필요성을 고찰하였다.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.49-50
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• 2015

Piezoelectric elements are one of good candidates able to replace motors in various electronics devices. It is slim and compact and low power consumption compare to motors. Linear regulator or class-D amplifier are generally used for piezoelectric element driver, however, suffers from severe power consumption. In this paper, electrical modeling of piezoelectric element will be presented and switching losses on the driver due to the parasitic capacitance will be analyzed. And new ZVS full bridge converter with an inductor will be proposed so as to reduce the power losses.