• Title/Summary/Keyword: Light Control

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Preparation and Characterization of Deoxycholic Acid-Conjugated Low Molecular Weight Water-Soluble Chitosan Nanoparticles for Hydrophobic Antifungal Agent Carrier (소수성 항진균제 전달체로 응용하기 위한 데옥시콜릭산이 결합된 저분자량 수용성 키토산 나노입자의 제조와 특성)

  • Choi, Chang-Yong;Jung, Hyun;Nam, Joung-Pyo;Park, Yoon-Kyung;Jang, Mi-Kyeong;Nah, Jae-Woon
    • Polymer(Korea)
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    • v.33 no.4
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    • pp.389-395
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    • 2009
  • To develop the carrier of hydrophobic antifungal agents based on low molecular weight water-soluble chitosan (LMWSC), LMWSC was chemically modified with deoxycholic acid (DA) which is one of the bile acid as a hydrophobic group. The nanoparticles (WSCDA) using DA conjugated LMWSC were characterized using dynamic light scattering (DLS) and transmittance electron microscope (TEM). The particle size of WSCDA ranged from 250 to 350 nm and increased with the number of DA substitution. The loaded itraconazole as an antifungal agent WSCDA nanoparticles (WSCDA-ITCN) were prepared by solvent evaporation method. The drug content and the loading efficiency were investigated approximately $9{\sim}10%$ and $61{\sim}68%$ by UV spectrophotometer, respectively. The release of drug from nanoparticles was slow and showed sustained release characteristics. Based on the results of release study that the higher DA contents in WSCDA, the slower the releasing rate, the WSCDA-ITCN could be used as an excellent antifungal agent.

A Study on the Effect of Gamma Background in Low Power Startup Physics Tests (저출력 노물리 시험에서의 감마 Background의 영향에 관한 연구)

  • Bae, Chang-Joon;Lee, Ki-Bog
    • Nuclear Engineering and Technology
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    • v.25 no.3
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    • pp.361-370
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    • 1993
  • Low power physics tests should be peformed for the domestic pressurized light water reactors (PWRs) after refueling. The tests are peformed to ensure that operating characteristics of the core are consistent with predictions and that the core can be operated as designed. But in some low power physics tests, slow but steady reactivity increasing phenomena were noticed after step reactivity insertion by the control rod movement. These reactivity increasing phenomena are due to the low flux level and the gamma background because an uncompensated ion chamber (UIC) is used as the ex-core neutron detector. The gamma background may affect the results or the lour power physics tests. The aims or this paper are to analyze the grounds of such phenomena, to simulate a reference bank worth measurement test and to present a resolution quantitatively. In this study, the gamma background level was estimated by numerically solving the point kinetics equations accounting the gamma background effect. The reactivity computer check test was simulated to verify the model. Also, an appropriate neutron flux level was determined by simulating the reference bank worth measurement test. The determined neutron flux level is approximately 0.3 of the nuclear heating flux. This level is about 3 times as high as the current test upper limit specified in the test procedure. Then, the findings from this work were successfully applied to Kori unit 4 cycle 7 and Yonggwang unit 1 cycle 7 physics tests.

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Wavefront Compensation Using a Silicon Carbide Deformable Mirror with 37 Actuators for Adaptive Optics (적응광학계용 37채널 SiC 변형거울을 이용한 파면 보상)

  • Ahn, Kyohoon;Rhee, Hyug-Gyo;Lee, Ho-Jae;Lee, Jun-Ho;Yang, Ho-Soon;Kihm, Hagyong
    • Korean Journal of Optics and Photonics
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    • v.27 no.3
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    • pp.106-113
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    • 2016
  • In this paper, we deal with the wavefront compensation capability of a silicon carbide (SiC) deformable mirror (DM) with 37 actuators for adaptive optics. The wavefront compensation capability of the SiC DM is predicted by computer simulation and examined by actual experiments with a closed-loop adaptive optics system consistsing of a light source, a phase plate, a SiC DM, a high speed Shack-Hartmann sensor, and a control computer. Distortion of wavefront is caused by the phase plate in the closed-loop adaptive optics system. The distorted wavefront has a peak-to-valley (PV) wavefront error of $0.3{\mu}m{\sim}0.9{\mu}m$ and root-mean-square (RMS) error of $0.06{\mu}m{\sim}0.25{\mu}m$. The high-speed Shack-Hartmann sensor measures the wavefront error of the distortion caused by the phase plate, and the SiC DM compensates for the distorted wavefront. The compensated wavefront has residual errors lower than $0.1{\mu}m$ PV and $0.03{\mu}m$ RMS. Consequently, we conclude that we can compensate for the distorted wavefront using the SiC DM in the closed-loop adaptive optics system with an operating frequency speed of 500 Hz.

A Study on the Stability and Clinical Trial for the Cream Containing Inula britannica Flower Extract (금불초 꽃 추출물 함유 크림의 안정성 평가 및 인체 시험)

  • Kim, Jung-Eun;Kim, A-Reum;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.37 no.2
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    • pp.129-136
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    • 2011
  • The moisturizing effect and stability of a cream containing 0.25 % Inula britannica flower ethyl acetate fraction were investigated. The pH, viscosity, and absorbance were measured under 4 different temperature conditions(4, 20, 37, and $45^{\circ}C$) and under the sun light at 2 week intervals for 12 weeks. The variations in pH and viscosity of all experimental creams were similar to those of control cream. The absorbance variations of the extract from experimental cream at 330 nm were in the order: under the sun > 45 > 37 > 25 > $4^{\circ}C$. It shows that ethyl acetate fraction in the cream can be oxidized under the sun. In addition, any change in color or smell was not observed through 12 weeks of the experimental period. These results showed that the cream were stable. Accordingly, it is suggested that further study is needed to provide more information to the manufacturers, who are seeking for the application of the extract to improve the anti-oxidant and antibacterial activities and stability of cosmetic products.

The Effect of Red Ginseng on Ultraviolet B-induced Skin Damages in Mouse (자외선 B 조사 마우스에서 피부손상에 대한 홍삼의 효과)

  • Lee, Hae-June;Kim, Se-Ra;Kim, Joong-Sun;Moon, Chang-Jong;Kim, Jong-Choon;Bae, Chun-Sik;Jang, Jong-Sik;Jo, Sung-Kee;Kim, Sung-Ho
    • Journal of Ginseng Research
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    • v.30 no.4
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    • pp.194-198
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    • 2006
  • The effects of red ginseng (RG) on the changes of ultraviolet (UV) light B radiation-induced apoptotic sun-burn cell (SBC) and epidermal ATPase-positive dendritic cell (DC) in SKH 1-hr or ICR mouse were investigated. The mice were treated with UVB ($200mJ/cm^2$) and were sacrificed 24 hours later. RG (50 mg/kg of body weight) or vehicle (saline) was given i.p. at 36 and 12 hours before irradiation, and 30 minutes after irradiation. RG cream (0.2%) or cream base (vehicle) was also topically treated at 24 hours and 15 minutes before irradiation, and immediately after irradiation. The skin of SKH 1-hr mouse prepared from the back of untreated mice exhibited about 0.3 SBC/cm length of epidermis, and 24 hours after UV irradiation, the applied areas show an increased number of SBCs. But the frequency of UVB-induced SBC formation was significantly reduced by intraperitoneal injection of RG extract. The numbers of DC in normal ICR mouse were $628.00{\pm}51.56\;or\;663.20{\pm}62.58\;per\;mm^2$ of ear epidermis. By 1 day after UVB treatment, the number of ATPase-positive $cells/mm^2$ were decreased by 39.0% or 27.1% in i.p. or topical application group with vehicle. The frequency of UVB ($200mJ/cm^2$)-induced DC decrease was reduced by treatment of RG as 31.3% in i.p. group and 22.4% in topical application group compared with the irradiation control group. The results presented herein that RG administration could reduce the extent of skill damages produced by UVB.

An Investigation of Caretakers Needs for Changes in Electric Wheelchairs (간병인의 전동휠체어 사용에 대한 만족도 조사)

  • Lee, Jung Ah;Lee, Bum-Suk;Choi, Hyun;Yoo, Sung Moon;Yang, Sung Pil;Bae, Jae Hyuk;Pak, Han Ram
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.10 no.3
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    • pp.177-184
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    • 2016
  • The purpose of this study was to investigate caretakers' demands and request in electric wheelchairs. The survey included the usability questionnaire (safety, operability, satisfactions) which were selected by opinions of caretakers and specialist of rehabilitation for electric wheelchairs. The survey also included questionnaires consisting of such questions as to demographic information, care experience, care time, and care burden, and demand for folding electric wheelchairs. Participants were fifty caretakers of electric wheelchair users. Caretakers' average age was 54.54years, and the average duration of their care experience was 80.98 months with average care time 9.80 hours per day. In safety and operability, most of participants were mostly satisfied. However, in satisfaction of weight and clean of electric wheelchairs was dissatisfied. They reported that the biggest problem of electric wheelchairs were too heav and difficult to control and that the greatest difficulty in helping electric wheelchair users was helping them with transfer to and from the wheelchair. They also need their prefer to develop folding electric wheelchairs. In this study, caretakers emphasized necessity of development light, easy to storage and clean electric wheelchairs. In conclusion, it is required to develop folding electric wheelchairs to reflect caretaker's opinions.

Localization of the Neurons Projecting to the Gallbladder Meridian (족소양담경(足少陽膽經)에서 투사(投射)되는 신경원(神經元)의 표지부위(標識部位)에 대한 연구(硏究))

  • Ryuk Sang-Won;Lee Kwang-Gyu;Lee Sang-Ryoung;Kim Jum-Young;Lee Chang-Hyun;Lee Bong-Hee
    • Korean Journal of Acupuncture
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    • v.17 no.1
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    • pp.101-121
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    • 2000
  • The purpose of this morphological studies was to investigate the relation to the meridian, acupoint and nerve. The common locations of the spinal cord and brain projecting to the the gallbladder, GB34 and common peroneal nerve were observed following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV), into the gallbladder, GB34 and common peroneal nerve of the rabbit. After survival times of 96 hours following injection of PRV, the thirty rabbits were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by PRV immunohistochemical staining method, and observed with light microscope. The results were as follows: 1. In spinal cord, PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in thoracic, lumbar and sacral spinal segments. Densely labeled areas of each spinal cord segment were founded in lamina V, VII, X, intermediolateral nucleus and dorsal nucleus. 2. In medulla oblongata, The PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in the A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nucleus, medullary reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus, gigantocellular nucleus, lateral paragigantocellular nucleus, principal sensory trigeminal nucleus and spinal trigeminal nucleus. 3. In Pons, PRV labeled neurons were parabrachial nucleus, Kolliker-Fuse nucleus and cochlear nucleus. 4. In midbrain, PRV labeled neurons were founded in central gray matter and substantia nigra. 5. In diencephalon, PRV labeled neurons were founded in lateral hypothalamic nucleus, suprachiasmatic nucleus and paraventricular hypothalamic nucleus. 6. In cerebral cortex, PRV labeled neuron were founded in hind limb area.This results suggest that PRV labeled common areas of the spinal cord projecting to the gallbladder, GB34 and common peroneal nerve may be first-order neurons related to the somatic sensory, viscero-somatic sensory and symapathetic preganglionic neurons, and PRV labeled common area of the brain may be first, second and third-order neurons response to the movement of smooth muscle in gallbladder and blood vessels.These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory system monitoring the internal environment, including both visceral sensation and various chemical and physical qualities of the bloodstream. The present morphological results provide that gallbladder meridian and acupoint may be related to the central autonomic pathways.

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Mode of Action of the New Diphenyl Ether Herbicide KC6361 (새로운 백화형 디페닐에테르계 화합물 KC-6361의 제초작용기작)

  • Kim, J.S.;Kim, T.J.;Kim, Y.S.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.14 no.2
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    • pp.81-93
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    • 1994
  • This study was conducted to characterize herbicidal activity of the new type diphenylether compounds inducing bleaching(whitening) in relation to their chemical structures and to find out the herbicidal action mechanism. Bleaching was highly appeared in the compounds which have short chain alkyl or allyl group of cabamoyl type in meta position of A ring and nitro group in para position of B ring, and KC6361 showed the highest efficacy among these derivatives. Rice was tolerant to KC6361 at 2.0kg/ha. The applications of this compound at 0.25~1.0kg/ha provided acceptable control of the various weeds including large crabgrass, barnyardgrass, pigweed and so on. In the dark condition, KC6361 decreased carotenoid contents but increased chlorophyll in etiolated cucumber cotyledon. By the increase of light intensity, the carotenoid biosynthesis was more inhibited than the chlorophyll biosynthesis. The incorporation of $C^{14}$-acetate into lipid was slightly inhibited. Both KC6361 and norflurazon stimulated growth of dwarf rice(cv. Daneunbanju). These results suggest that both KC6361 and norflurazon may have the same action sites. To confirm this hypothesis, the changes of carotenoid intermediates in cucumber cotyledon and barnyardgrass leaf treated with KC6361 were investigated. Phytoene and phytofluene were increased but ${\beta}$-carotene was decreased, indicating that KC6361 inhibited phytoene and/or phytofluene dehydrogenase like norflurazon.

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A STUDY ON THE MANDIBULAR MOMENTS ACCORDING TO ANTERO-POSTERIOR PLACEMENT OF PIVOT ON LOWER NATURAL DENTITION (자연치열에 설치한 pivot의 전후방 일치변화에 따른 하악의 moment에 관한 연구)

  • Lee Hyun-Shick;Park Nam-Soo;Choi Dae-Gyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.31 no.3
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    • pp.394-410
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    • 1993
  • This study was accomplished for appreciation of the mandibular moments according to antero- posterior movement of pivot placed on the lower natural dentition. For this study, 20 subjects(male, $21\sim30$ yrs., average age 24) in the category of normal occlusion were selected, and the intraoral Vitallium clutches were cast and fabricated for each subjects. A 2-dimension PSD(Position Sensitive Detector, Hamamatsu Photonics Co., Japan) was attached to maxillary clutch in a mode of three dimensional control and LED (Light Emit Diode, Hamamatsu Photonics Co., Japan) was set up on mandibular clutch. Both clutches were set into oral cavity of each subjects and adjusted. Then the subjects were allowed to intercuspated with maximal bite force while the pivoting ball in the mid-line moving from anterior toward posterior position. The displacement scales were recorded by CCD camera(Sony, CCD-TR-705) and VCR, The conclusions were as follows : 1. When the subject was allowed to bite the metal pivoting ball in the midline of lower dentition with maximal bite force voluntarily while moving from lower central incisor to canine, 1st premolar, End premolar, 1st molar and 2nd molar. The lever actions on the pivot were revealed in all subjects. The equilibrium of moment were revealed on the pivots of 1st premolar(14 subjects), End premolar(4 subjects), and canine(2 subjects) areas. 2. The changes of loading on the TMJ according to antero-posterior positional changes of metal pivoting ball were able to recognize as follow. Compression on the TMJ was increased when the pivot moves anteriorly from the equilibrium point, and tension on the TMJ was increased when posteriorly. 3. 13 subjects were recognized their habitual chewing sides(Rights, Left8), and 7 subjects were not. During maximal biting, mandible was displaced toward their habitual chewing sides on the metal pivoting ball in the frontal plane. 4. In cephalometric analysis, the average genial angle of 20 subjects was $116.75^{\circ}$ and the average mandibular body length was 79.77mm. The equilibrium points of mandibular moment were positioned more posteriorly in the subjects having larger Genial angle than in the smaller(p<0.05). Relationships among the angle between FH plane and occlusal plane, the angle between occlusal plane and mandibular plane , and mandibular body length were not significant(p>0.05).

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2D/3D Visual Optical Inspection System for Quad Chip (Quad Chip 외관 불량 검사를 위한 2D/3D 광학 시스템)

  • Han, Chang Ho;Lee, Sangjoon;Park, Chul-Geon;Lee, Ji Yeon;Ryu, Young-Kee;Ko, Kuk Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.684-692
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    • 2016
  • In the manufacturing process of the LQFP/TQFP (Low-profile Quad Flat Package/Thin Quad Flat Package), the requirement of a 3 dimensional inspection is increasing rapidly and a 3D inspection of the shape of a chip has become an important report of quality control. This study developed a 3 dimensional measurement system based on PMP (Phase Measuring Profilometry) for an inspection of the LQFP/TQFP chip and image processing algorithms. The defects of the LQFP/TQFP chip were classified according to the dimensions. The 2 dimensional optical system was designed by the dorm illumination to achieve constant light distribution, In the 3 dimensional optical system, PZT was used for moving 90 degree in phase. The problem of 2 ambiguity was solved from the measured moir? pattern using the ambiguity elimination algorithm that finds the point of ambiguity and refines the phase value. The proposed 3D measurement system was evaluated experimentally.