Wetlands are one of the most representative groundwater dependent ecosystems(GDEs) that require access to groundwater on a permanent or intermittent basis to maintain their biological communities and ecological processes. In this study, the seasonal characteristics of the GDEs in Baekseok Reservoir Wetland were evaluated through the monitoring of the temporal and spatial community of benthic macroinvertebrates in the wetland. The appearance of benthic macroinvertebrates appearance was changed seasonally depending on environmental factors such temperature, precipitation and water level for their habitat and it also showed the clear spatial difference in the wetland. The scores of Diversity index(H'), Richness Index (R1) and the Ecological score of benthic macroinvertebrates (TESB/AESB) were relatively high at St.3 and 4(i.e., north area) where groundwater inflows into wetland(i.e., high 222Rn conc.). The statistical analysis (ANOVA test and PCA) investigated the correlation among the benthic macroinvertebrates' community, groundwater level, wetland water level and water quality. The results showed that the community of benthic macroinvertebrates at St. 3 and 4 in Baekseok Reservoir Wetlands was spatially dependent on groundwater level and groundwater inflow. The characterization and assessment of GDEs requires understanding the hydrological, biogeochemical and biological process and this study will provide information for characterization and assessment of GDEs.
Kim, Hyo-Chul;Cho, Heung-Rae;Lee, Ju-Heun;Lee, Deok-Jae;An, Se-Hwan;Lee, Man-Hee;Joo, Ji-Han;Kim, Hong-Rak
The Journal of the Institute of Internet, Broadcasting and Communication
/
v.21
no.6
/
pp.25-32
/
2021
In this study, it proposes a mode converter that is relatively easy to implement and can shorten the transmission line length of the final combining port and it was fabricated and tested by applying it to an 8-way spatial combiner. The proposed mode converter converts the signal converted from the doorknob-shaped circular disk connected to the ground into the TM01 mode by opening it in the circular waveguide. The 8-way waveguide spatial combiner is designed and implemented so that 8 signals input from the H-plane are combined in a circular waveguide at the center, and the final combining mode is TM01. The test results confirmed excellent performance with an insertion loss of less than 0.4dB and a combining efficiency of 95% or more. In addition, it was confirmed that it is suitable for high output by calculating the breakdown voltage and discharge threshold power of the new mode conversion structure through electric field analysis. The results confirmed through this study are expected to be applicable to high-power, high-efficiency SSPA in various fields in the future.
Shin, Hyun Ho;Ryu, Hee Ryong;Yu, In Ho;Cho, Myeong Whan;Seo, Tae Cheol;Kim, Seung Yu;Choi, Man Kwon
Journal of Bio-Environment Control
/
v.30
no.4
/
pp.410-418
/
2021
This study was conducted in 8.2m wide single-span greenhouse to investigate the effect of presence or absence of rafter steel pipe joint and foundation conditions on greenhouse structural performance. Structural performance was evaluated by static loading test using the structural performance evaluation system for single-span greenhouse. The measured displacement was compared with the predicted result by numerical analysis. The displacement of each measurement location showed a significant difference regardless of the conditions of the foundation and presence or absence of rafter steel pipe joint. Compared to the hinge conditions, the difference in structural performance of the greenhouse in the fixed conditions was seen to be relatively large. The difference in structural performance according to presence or absence of rafter steel pipe joints, the lateral stiffness of the joint was 8.1% greater.
A review about the application of response surface methodology in the optimization of food technology is presented. The theoretical principles of response surface methodology and steps for its application are described. The response surface methodologies : three-level full factorial, central composite, Box-Behnken, and Doehlert designs are compared in terms of characteristics and efficiency. Furthermore, recent references of their uses in food technology are presented. A comparison between the response surface designs (three-level full factorial, central composite, Box-Behnken and Doehlert design) has demonstrated that the Box-Behnken and Doehlert designs are slightly more efficient than the central composite design but much more efficient than the three-level full factorial designs.
The consumption of beverages among children is rising. The purpose of this study was to examine the effect of kid's drink on dental resin-based pit and fissure sealant. Pororo, I-kicker, Sunkist kids were included in the experimental groups, and Samdasu was included in the control group. A conventional dental sealant material ($Clinpro^{TM}Sealant^{(R)}$) was selected for this study. Resin specimens (8 mm in diameter and 1 mm in thickness) were prepared according to manufacturers' instructions and the initial roughness (Ra) was then measured. The pH of all the four groups was measured using a pH meter. The specimens were individually immersed in 5 ml of the experimental solutions and stored at $37^{\circ}C$ for 72 hours. Following this, the surface roughness of the resin specimens was measured by Surftest. The concentration of residual monomer released was determined by high performance liquid chromatography (HPLC). The surface morphology of the resin specimen was evaluated before and after storage by scanning electron microscopy (SEM). Data were statistically analyzed using Kruskal-Wallis and Duncan's test. The results showed that all the children's beverages examined in this study contained citric acid. The pH of I-kicker was the lowest ($3.03{\pm}0.01$), followed by that of Sunkist kids ($3.26{\pm}0.02$) and Pororo ($3.47{\pm}0.02$). We observed an increase in the surface roughness of resin specimens after 72 h of immersion in all the beverages tested (p<0.05). There was matrix degradation after immersion, visualized on SEM image, in all the beverage groups. Bisphenol-A-glycidyl methacrylate was not detected after 72 hours, but triethylene glycol dimethacrylate levels were increased in all the beverages tested during the 72 hours by HPLC. These results suggest that intake of beverages containing acid can cause degradation of the resin-based pit and fissure sealants in children.
Journal of the Korean Applied Science and Technology
/
v.36
no.2
/
pp.592-599
/
2019
This study is to stabilize insoluble and unstable active ingredient which is Idebenone (INCI name: hydroxydecyl ubiquinone) in a multi-lamellar vesicle (MLV) and to stabilize it in the skin care cosmetics. Idebenone is good effective raw material in the treatment of Alzheimer's disease in the medical field and a powerful antioxidant in dermatology. It is well known as a substance that inhibits the formation of melanin and cleans the skin pigment. However, it did not dissolve in any solvent and it was difficult to apply in cosmetic applications. Niosome vesicle was able to develop a nano-particle by making a multi-layer of idebenone encapsulated with a nonionic surfactant, hydrogenated lecithin and glycine soja (soybean) sterols and passing it through a high pressure microfluidizer. Idebenone niosome vesicle (INV) has been developed to have the ability to dissolve transparently in water and to promote transdermal penetration. The appearance of the INV was a yellowish liquid having specific odor, and the particle size distribution of INV was about 10~80 nm. The pH was 5~8 (mean=6.8). This capsulation with idebenone was stored in a $45^{\circ}C$ incubator for 3 months and its stability was observed and quantitatively measured by HPLC. As a result, the stability of the sample encapsulated in the niosome vesicle (97.5%) was about 66.3% higher than that of the non-capsule sample of 32.5%. Idebenone 1% INV was used for the efficacy test and clinical trial evaluation as follows. The anti-oxidative activity of INV was 38.2%, which was superior to that of 12.8% tocopherol (control). The melanin-reducing effect of B16 melanoma cells was better than INV (17.4%) and Albutin (control) (9.6%). Pro-collagen synthesis rate was 128.2% for INV and 89.3% for tocopherol (control). The skin moisturizing effect was 15.5% better than the placebo sample. The elasticity effect was 9.7% better than the placebo sample. As an application field, INV containing 1% of idebenone is expected to be able to develop various functional cosmetic formulations such as skin toner, ampoule essence, cream, eye cream and sunblock cream. In addition, it is expected that this encapsulated material will be widely applicable to emulsifying agents for skin use in the pharmaceutical industry as well as the cosmetics industry.
Jeon, Rakyoung;Kwon, Kihyun;Yoon, Soonmin;Park, Myungkyu;Lee, Changha;Oh, Min
Korean Chemical Engineering Research
/
v.57
no.4
/
pp.475-483
/
2019
Special chemical warfare agents are lethal gases that attack the human respiratory system. One of such gases are blood agents that react with the irons present in the electron transfer system of the human body. This reaction stops internal respiration and eventually causes death. The molecular sizes of these agents are smaller than the pores of an activated carbon, making chemical adsorption the only alternative method for removing them. In this study, we carried out a Computational Fluid Dynamics simulation by passing a blood agent: cyanogen chloride gas through an SG-1 gas mask canister developed by SG Safety Corporation. The adsorption bed consisted of a Silver-Zinc-Molybdenum-Triethylenediamine activated carbon impregnated with copper, silver, zinc and molybdenum ions. The kinetic analysis of the chemical adsorption was performed in accordance with the test procedure for the gas mask canister and was validated by the kinetic data obtained from experimental results. We predicted the dynamic behaviors of the main variables such as the pressure drop inside the canister and the amount of gas adsorbed by chemisorption. By using a granular packed bed instead of the Ergun equation that is used to model porous materials in Computational Fluid Dynamics, applicable results of the activated carbon were obtained. Dynamic simulations and flow analyses of the chemical adsorption with varying gas flow rates were also executed.
Domestic hydraulic drifters till now have been developed by benchmarking products from overseas leading companies. However, they do not have excellent impact performance as they are not suitable for characteristics (large flow rate and low pressure) of Korean hydraulic drill power pack, and therefore, research on the optimum design has not made much headway. This study performs multi-objective function optimization for hydraulic drifters whose capacity has been redesigned to deal with the large flow rate, and also with the help of this function, it aims to improve impact power and reduce supply and surge pressure. A summary of the research study is as follows: First, we set goals for improving impact power, supply pressure, and surge pressure, and then perform multi-objective function optimization on them. After that, we secure the reliability of the optimized analytical model by comparing the test results of the prototype built by the optimized design with the analysis results of the analytical model. This study used SimulationX, that is the hydraulic system analysis software, and EasyDesign, which is a multi-objective function optimization program. Through this research, we have achieved the results that satisfy the goal of developing high power drifters suitable for Korean type hydraulic drills.
Gronqvist, Gabriella V.;Corner-Thomas, Rene A.;Kenyon, Paul R.;Stafford, Kevin J.;Morris, Stephen T.;Hickson, Rebecca E.
Asian-Australasian Journal of Animal Sciences
/
v.31
no.12
/
pp.1991-2000
/
2018
Objective: Triplet-born lambs are less likely to survive to weaning than twin-born or single-born lambs. Appropriate ewe-lamb bonding behaviours and lamb vigour behaviours are necessary for survival of lambs. The aim of this experiment was to determine whether maternal nutrition during late pregnancy influenced behaviour of the ewe and her lambs soon after birth, and to determine whether mid-pregnancy body condition score (BCS) influenced any behavioural response. Methods: The experiments included ewes that were in BCS 2.0, 2.5, or 3.0 in mid-pregnancy and were fed either ad libitum or to pregnancy-maintenance requirements in late-pregnancy (day 115 until 136 in experiment one, and day 128 until 141 in experiment two). The time taken for lambs to stand, contact dam, suck from dam and follow dam was recorded three to 18 h after birth. The number of high- and low-pitched bleats emitted by the ewe and lambs was recorded, along with maternal behaviour score (MBS) of the ewe. Lambs in experiment two underwent a maternal-recognition test at 12 or 24 h. Results: There were significant effects of feeding treatment on bleating behaviour of ewes and lambs, but these were inconsistent among BCS groups and between experiments. Lamb vigour behaviours were not affected by feeding treatment. In experiment one, there was no effect of feeding treatment or BCS on MBS, but in experiment two, ewes in BCS3 in mid-pregnancy had greater MBS than ewes in BCS2 in mid-pregnancy (MBS 3.1/5 vs MBS 2.1/5; p<0.05). Conclusion: Given there were no repeatable effects on behaviour of ewes and lambs, ad libitum feeding rather than feeding for pregnancy-maintenance requirements cannot be used to improve behaviours soon after birth of triplet-bearing ewes in BCS 2-3 and their lambs in extensive pastoral conditions.
Objectives: This study assessed the accuracy of the 24-hour diet recall method for estimating the energy intake of elderly men using the doubly labeled water as a reference method. Methods: Seventeen subjects (mean age $72.5{\pm}3.9years$), who maintained the same body weight during the two weeks study period, were included in this study. Three 24-hour diet recalls (two weekdays and one weekend) were obtained over a 14 day period to estimate the mean energy intake. The total energy expenditure was measured over the same 14 days using the doubly labeled water method. The total energy intake and total energy expenditure were compared by paired t-test. Results: The total energy intake from the 24-hour diet recalls method was $2536.7{\pm}350.6kcal/day$, and the total energy expenditure from the doubly labeled water method was $2659.8{\pm}306.8kcal/day$. The total energy intake was slightly under-reported by $-123.2{\pm}260.8kcal/day$ (-4.4%). On the other hand, no significant difference was observed between the total energy intake and total energy expenditure of the subjects (p=0.069). The percentage of accurate predictions was 64.7%. The correlation between the total energy intake and total energy expenditure was statistically significant (r=0.697, p<0.005). Conclusions: The present study supports the use of the 24-hour diet recall method to estimate the mean energy intake in elderly men group. More studies are needed to assess the validity of 24-hour diet recall method in other population groups, including elderly women, adults and children.
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.