Purpose: Analysis performance for spectacle lens which sales in domestic market and optimization design a spectacle lens which is corrected aberration. Methods: Measured center thickness, radius and aspherical surface coefficient for spherical and aspherical lenses which were ${\pm}$5.00D. Refractive index for every lens was 1.6 and they came from 4 different companies. I used 3 types of equipment to measure lenses. ID-F150 (Mitutoyo) : Center Thickness, FOCOVISION (SR-2, Automation Robotics) : Radius, PGI 1240S (Taylor Hobson) : Aspherical surface coefficient. Designed a lens which had 27 mm of distance from lens rear surface to center of eye, 4 mm of pupil diameter and small aberration on center vision $30^{\circ}C$. To shorten axial distance compared with the measured lens rise merits for cosmetic. Lens Design tool was CODE V (Optical Research Associates). Results: -5.00D aspherical lens had somewhat high astigmatism and distortion compared with the spherical lens. But it had a merit for cosmetic because of short axial height and decrease edge thickness. Improved a performance of distortion and ascertain merits for cosmetic due to short axial height and decrease edge thickness same as (-) lens in case of +5.00 aspherical lens. Though an optimization process front surface aspherical lens had a good performance for astigmatism and distortion and the merit for beauty compared with measured spherical lens. Conclusions: Design trend for domestic aspherical lens is decrease axial height and thickness to increase a merit for cosmetic not but increase performance of aberration. From design theory for optimization design front surface aspherical spectacle lens which has improved performance of aberration and merit for cosmetic at the same time compared with the measured lens. Expect an improved performance from design back aspherical lens compared with front aspherical lens.
Journal of Dental Rehabilitation and Applied Science
/
v.25
no.4
/
pp.349-360
/
2009
Purpose: As the esthetic demands of dental implant patients are increased, the demands of zirconia as implant abutment material are also increased. It has non-metalic color, good biocompatibility, high strength and high toughness. Even thought the advatage of zirconia abutment, there are a few studies about mechanical properties of zirconia abutment. This study evaluated the mecanical strength with compressive bending strength and endurance limit of implant-zirconia abutment assembly. Materials and Methods: Static and cyclic loading of implant-Zirconia abutment assembly were simulated under worst case condition according to ISO. Test groups were implants of external butt joint with straight regular diameter and angled regular diameter zirconia abutment, implant of external butt joint with narrow straight diameter zirconia abutment and implant of internal conical joint with straight narrow diameter zirconia abutment. All test group were evaluated the mecanical strength with compressive bending strength and endurance limit. After fatique testing, fracture surface were examined by SEM. Results: The compressive bending strengths exceed 927N. Regular diameter zirconia abutment were stronger than narrow diameter zirconia abutment(P<.05). The endurance limits ranged from 503N to 868N. Conclusion: Within the limitation of this study, zirconia implant abutment exceeded the estabilished values for maximum incisal biting forces reported in the literature.
Since a Compton camera has high detection sensitivity due to electronic collimation and a good energy resolution, it is a potential imaging system for nuclear medicine. In this study, we investigated the feasibility of a Compton camera for multi-tracer imaging and proposed a rotating Compton camera to satisfy Orlov's condition for 3D imaging. Two software phantoms of 140 and 511 keV radiation sources were used for Monte-Carlo simulation and then the simulation data were reconstructed by listmode ordered subset expectation maximization to evaluate the capability of multi-tracer imaging in a Compton camera. And the Compton camera rotating around the object was proposed and tested with different rotation angle steps for improving the limited coverage of the fixed conventional Compton camera over the field-of-view in terms of histogram of angles in spherical coordinates. The simulation data showed the separate 140 and 511 keV images from simultaneous multi-tracer detection in both 2D and 3D imaging and the number of valid projection lines on the conical surfaces was inversely proportional to the decrease of rotation angle. Considering computation load and proper number of projection lines on the conical surface, the rotation angle of 30 degree was sufficient for 3D imaging of the Compton camera in terms of 26 min of computation time and 5 million of detected event number and the increased detection time can be solved with multiple Compton camera system. The Compton camera proposed in this study can be effective system for multi-tracer imaging and is a potential system for development of various disease diagnosis and therapy approaches.
Jo, JungHeum;Park, Jun-sik;Kim, Sung-Yeon;Kwon, Myung hee;Kim, Ki Youn;Choi, Jeong-Hak;Seo, SungChul
Journal of Korean Society of Occupational and Environmental Hygiene
/
v.26
no.3
/
pp.324-333
/
2016
Objectives: We aimed to compare the sampling performance of different flow-based impactor samplers for collecting fungal spores and bacteria and to explore the association of the level of bioaerosols with activity patterns of occupants in daycare center settings. Methods: For comparison of sampling performance, two different flow-based samplers (greater than 100 L/min or not) were selected; a low flow-based sampler (one-stage Andersen sampler) and two high flow-based samplers (DUO SAS SUPER 360 sampler, BUCK bio-culture sampler). We collected airborne mold and bacteria in 30 daycare centers with various levels of contaminated air. Three repeat samplings per each sampler were performed. Mold and bacteria were grown for 96 hours at $25{\pm}1^{\circ}C$ and 48 hours at $35{\pm}1^{\circ}C$, respectively. The Andersen and SAS samplers were used for investigating the association between the level of bioaerosols and the activity patterns of occupants in daycares. Particular matters 10($PM_{10}$), temperature, and relative humidity were monitored as well. Samplings were carried out with one-hour interval from 9 to 5 O'clock. For statistical comparisons, Kruskal-Wallis test, Wilcoxon's signed rank test, and multiple regression analysis were carried out. Results: The airborne level of molds by the low flow-based sampler were significantly higher than that of high flow-based samplers (indoor, P=0.037; outdoor, P=0.041). However, no statistical difference was observed in the airborne level of bacteria by each sampler. Also the level of bioaerosols varied by the time, particularly with different activity patterns in daycare centers. The higher level of mold and bacteria were observed in play time in indoor. Similarly, the concentrations of $PM_{10}$ were significantly associated with the level of bioaerosols (P<0.05). Conclusions: Our findings indicate that the flow rate of sampler, rather than total air volume, could be able to affect the results of sampling. Also, the level of airborne mold and bacteria vary behavior patterns of occupants in indoor of daycare settings. Therefore, different samplers with other flow rate may be selected for mold or bacteria sampling, and activity patterns should be considered for bioaerosol sampling as well.
Kim, Jung-Yul;Park, Hoon-Hee;NamKoong, Hyuk;Cho, Suk-Won;Kim, Jae-Sam;Lee, Chang-Ho
The Korean Journal of Nuclear Medicine Technology
/
v.12
no.1
/
pp.33-38
/
2008
Purpose: The Gated cardiac blood pool scan is non-invasive method that a quantitative evaluation of left ventricular function. Also this scan have shown the value of radionuclide ejection fraction measurements during the course of chemotherapy as a predictor of cardiac toxicity. Therefore a reliable method of monitoring its cardiotoxic effects is necessary. the purpose of this study is to minimize the overestimate of left ventricular ejection fraction (LVEF) by modified body position to reduce the influence of scattered rays from surrounding organs of the heart in the background region of interest. Materials and Methods: Gated cardiac blood pool scan using in vivo $^{99m}Tc$-red blood cell (RBC) was carried out in 20 patients (mean $44.8{\pm}8.6$ yr) with chemotherapy for a breast carcinoma. Data acquisition requires about 600 seconds and 24 frames of one heart cycle by the multigated acquisition mode, Synchronization deteriorates toward the end of the cycle and with the distance from the trigger signal (R-wave) by ECG gating. Gated cardiac blood pool scan was studied with conventional method (supine position and the detector head in $30-45^{\circ}$ left anterior oblique position and caudal $10-20^{\circ}$ tilt) and compared with modified method (left lateral flexion position with 360 mL of drinking water). LVEF analysis was performed by using the automatically computer mode. Results: The ROI counts of modified scan method were lower than LV conventional method ($1429{\pm}251$ versus $1853{\pm}243$, <0.01). And LVEF of modified method was also decrease compared with conventional method ($58.3{\pm}5.6%$ versus $65.3{\pm}6.1%$, <0.01). Imaging analysis indicated that stomach was expanded because of water and spleen position was changed to lateral inferior compared with conventional method. Conclusion: This study shows that the modified method in MUGA reduce the influence of scattered rays from surrounding organs. Because after change the body position to left lateral flexion and drinking water, the location of spleen, left lobe of liver and stomach had changed and they could escaped from background ROI. Therefore, modified method could help to minimize the overestimate LVEF (%).
Low density polyethylene (LDPE) films incorporated with 1% antimicrobial agents of Rheum palmatum extract, Coptis chinensis extract, and Ag-substituted inorganic zirconium matrix, were applied to modified atmosphere packaging of 200 g fresh strawberries. Plain LDPE film package, PVC wrap and perforative pinhole package of the film impregnated with 1% Rheum palmatum extract were also constructed for comparative purpose. All the packages were stored for 13 days at $5^{\circ}C$ and measured in package atmosphere, microbial count and quality attributes of the strawberry fruits. The antimicrobial LDPE films retarded the growth in total aerobic bacteria, lactic acid bacteria and yeast on the fruits, and resulted in significantly lower decay. The degrees of reduced microbial growth and fruit decay in the antimicrobial film packages were more pronounced, when applied by hermetical sealing to produce the modified atmospheres of low $O_2$ (<4.0%) and $CO_2$ concentrations with $6.3{\sim}9.0%$. The hermetically sealed packages of antimicrobial LDPE films also showed better retention of fruit firmness and did not give any negative effect on the physical and chemical qualities of strawberries.
Zr-Si binary alloys containing 0.01 to O.lwt.%Si were prepared to investigate the effect of Si on the corrosion behavior of Zr. Corrosion test was performed in pure water at 36$0^{\circ}C$ under a pressure of 2660psi for 100days. The alloys containing 0.01 wt. % and 0.05wt. %Si had the black and uniform oxide film and didn't show the transition of corrosion rate. However. the alloys containing O.lwt.%Si had white oxide film and showed the trasition of corrosion rate at 70 days corrosion test. The weight gain increased with the increasing Si content from 0.01 to 0.1 wt.%. The variation of Si contents had no effect on changing the oxide structure but had significant effect on the electrical resistivity of oxide. The electrical resistivity decreased with increasing Si content. The fraction of precipitates in the Zr-Si binary alloys. identified as tetragonal $Zr_{3}$Si increased with increasing Si content. The increase of the volume fraction of precipitates is thought to be responsible for the increase of weight gain due to short circuit effect of precipitate.
To evaluate antioxidant capacities and total phenolic, flavonoid, and catechin contents of pure green tea packaged in tea bags, green tea bags of 10 commercial brands were purchased and analyzed. Considering commonly used infusion methods, green tea bags were extracted using 150 mL of spring water at $70^{\circ}C$ for 2 min. Ten brands of green tea showed a wide range of total phenolic content (46.3-93.9 mg gallic acid equivalents/g), total flavonoid content (10.3-21.7 mg catechin equivalents/g), and antioxidant capacities (88.8-175.6 mg and 87.9-183.5 mg vitamin C equivalents/g for DPPH and ABTS assays, respectively). Total catechin content of green tea ranged from 33.8-74.7 mg/g, which corresponded to 43.0-108.3 mg/150 mL of cup. Collectively, these results suggest that daily consumption of 3.8-12.5 cups of green tea packaged in tea bags meets the recommended daily intake of catechins in green tea extract as a health functional foods in Korea.
Park, Seungbae;Kang, Dong Hyeon;Jin, Changbae;Kim, Hyoung Ja
Journal of the Korean Society of Food Science and Nutrition
/
v.46
no.2
/
pp.210-219
/
2017
This study aimed to establish an optimal extraction process and high-performance liquid chromatography (HPLC)-photodiode array (PDA) analytical method for determination of marker compounds, dihydrokaempferol (DHK) and 3-O-methylquercetin (3-MeQ), as a part of materials standardization for the development of health functional foods from stems of Opuntia ficus-indica var. saboten (OFS). The quantitative determination method of marker compounds was optimized by HPLC analysis, and the correlation coefficient for the calibration curve showed very good linearity. The HPLC-PDA method was applied successfully to quantification of marker compounds in OFS after validation of the method in terms of linearity, accuracy, and precision. Ethanolic extracts from stems of O. ficus-indica var. saboten (OFSEs) were evaluated by reflux extraction at 70 and $80^{\circ}C$ with 50, 70, and 80% ethanol for 3, 4, 5, and 6 h. Among OFSEs, OFS70E at $80^{\circ}C$ showed the highest contents of DHK and 3-MeQ of $26.42{\pm}0.65$ and $3.88{\pm}0.29mg/OFS100g$, respectively. Furthermore, OFSEs were determined for their antioxidant activities by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and lipid peroxidation (LPO) inhibitory activities in rat liver homogenate. OFS70E at $70^{\circ}C$ showed the most potent antioxidant activities with $IC_{50}$ values of $1.19{\pm}0.11$ and $0.89{\pm}0.09mg/mL$ in the DPPH radical scavenging and LPO inhibitory assays, respectively. To identify active components of OFS, various chromatographic separation of OFS70E led to isolation of 11 flavonoids: dihydrokaempferol, dihydroquercetin, 3-O-methylquercetin, quercetin, isorhamnetin 3-O-glucoside, isorhamnetin 3-O-galactoside, narcissin, kaempferol 7-O-glucoside, quercetin 3-O-galactoside, isorhamnetin, and kaempferol 3-O-rutinoside. The results suggest that standardization of DHK in OFSEs using HPLC-PDA analysis would be an acceptable method for the development of health functional foods.
Kwon, Jin Kyung;Kim, Seung Hee;Jeon, Jong Gil;Kang, Youn Koo;Jang, Kab Yeol
Journal of Bio-Environment Control
/
v.26
no.4
/
pp.353-360
/
2017
In this study, the design and performance test of the air to water heat pump capable of producing hot water for greenhouse heating by using the surplus solar heat inside the greenhouse and the air heat outside greenhouse as the selective heat source were conducted. The heat storage operations using the surplus solar heat and the outside air heat were designed to be switched according to the setting temperature of the greenhouse in consideration of the optimum temperature range of the crop. In the developed system, it was possible to automatically control the switching of heat storage operation, heating and ventilation by setting 12 reference temperatures on the control panel. In the selective heat storage operation with the surplus solar heat and outside air heat, the temperature of thermal storage tank was controlled variably from $35^{\circ}C$ to $52^{\circ}C$ according to the heat storage rate and heating load. The heat storage operation times using the surplus solar heat and outside air heat were 23.1% and 30.7% of the experimental time respectively and the heat pump pause time was 46.2%. COP(coefficient of performance) of the heat pump of the heat storage operation using the surplus solar heat and outside air heat were 3.83 and 2.77 respectively and was 3.24 for whole selective heat storage operation. For the comparative experiment, the heat storage operation using the outside air heat only was performed under the condition that the temperature of the thermal storage tank was controlled constantly from 50 to $52^{\circ}C$, and COP was analyzed to be 2.33. As a result, it was confirmed that the COP of the heat storage operation using the surplus solar heat and outside air heat as selective heat source and the variable temperature control of the thermal storage tank was 39% higher than that of the general heat storage operation using the outside air heat only and the constant temperature control of the thermal storage tank.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.