• 원예과학기술지
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• 제35권2호
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• pp.220-231
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• 2017

Grafting using a pumpkin (Cucurbita sp.) rootstock is an effective way to improve cucumber (Cucumis sativus) resistance to a combination of chilling and salinity stresses. We evaluated the tolerance of 15 pumpkin cultivars to chilling, salinity, and combined stresses at the germination and seedling stages. Selected plant characteristics, including germination rate, germination potential, germination index, plant height, stem thickness, fresh weight, and dry weight, were analyzed. We used the unweighted pair group method with arithmetic mean for cluster analyses to determine the stress tolerance levels of the pumpkin cultivars. The 15 cultivars were divided into three clusters: tolerant, moderately tolerant, and susceptible to stress treatments. The stress tolerances of all cultivars were variable in the germination and seedling stages, and most cultivars were not tolerant to individual treatments of chilling or salinity stresses at both stages. These results suggest that identifying suitable cultivars for use as rootstock during cucumber grafting should involve the evaluation of stress tolerance during different growth stages. Additionally, cultivars tolerant to chilling stress may not be tolerant to salinity stress; therefore, the choice of pumpkin rootstock should depend on where the grafted plant will be grown. Cultivars tolerant to a combination of chilling and salinity stresses may be useful as rootstock for cucumber grafting. Our findings may serve as reference material for choosing appropriate pumpkin rootstocks for cucumber grafting.

• Journal of applied mathematics & informatics
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• 제30권5_6호
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• pp.871-882
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• 2012

For a connected graph G of order $n$, an ordered set $S=\{u_1,u_2,{\cdots},u_k\}$ of vertices in G is a linear edge geodetic set of G if for each edge $e=xy$ in G, there exists an index $i$, $1{\leq}i$ < $k$ such that e lie on a $u_i-u_{i+1}$ geodesic in G, and a linear edge geodetic set of minimum cardinality is the linear edge geodetic number $leg(G)$ of G. A graph G is called a linear edge geodetic graph if it has a linear edge geodetic set. The linear edge geodetic numbers of certain standard graphs are obtained. Let $g_l(G)$ and $eg(G)$ denote the linear geodetic number and the edge geodetic number, respectively of a graph G. For positive integers $r$, $d$ and $k{\geq}2$ with $r$ < $d{\leq}2r$, there exists a connected linear edge geodetic graph with rad $G=r$, diam $G=d$, and $g_l(G)=leg(G)=k$. It is shown that for each pair $a$, $b$ of integers with $3{\leq}a{\leq}b$, there is a connected linear edge geodetic graph G with $eg(G)=a$ and $leg(G)=b$.

• 한국산학기술학회논문지
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• 제13권1호
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• pp.227-235
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• 2012

이 연구에서는 최근 국내에서 개발된 보행용 기능성 신발 중 걷기 효율성을 변화시키는 복합적 기능성 신발(double rocker sole;CDR)과 negative-heel rocker sole(NR)형태 신발의 근육 활성도를 비교하였다. 연구대상은 하지정형 외과적 질환이 없는 40-50대 중년여성 11명을 대상(연령 $47.33{\pm}4.4$, 신장 $158.00{\pm}3.3$cm, 체중 $59.50{\pm}6.1$, BMI $23.80{\pm}1.8kg/m^2$)으로 하였다. 연구결과 좌,우측의 내측광근, 비복근, 반건양근에서는 근활성도의 수준은 통계적으로 유의한 차이가 나타나지 않았지만, CDR신발이 전경골근에서 통계적으로 유의하게 높은 결과가 나타났다(p<.05). 걷기운 동시 동일한 조건속에 운동을 실시할 경우 신발 밑창의 변화를 통해 인위적으로 운동량을 증가시킬 수 있을 것이다.

• 천문학회보
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• 제36권2호
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• pp.125.2-125.2
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• 2011

We are developing medium resolution cross-dispersed silicon grisms in the near IR region ($1.45{\sim}5.2{\mu}m$). The grisms will be installed in MIMIR, a multifunction instrument at the Lowel Observatory, USA. The two devices are designed to cover H and K band and L and M band simultaneously. Our goal is to make grism with R=3000 at 1.2 arcsec slit. The Silicon has high refractive index (n=3.4 at $1.5{\mu}m$) which enhances the resolving power by up to 5 times when compared to conventional material such as BK-7 (n=1.5 at 1.5 ${\mu}m$). The bonded grisms will be installed in a filter wheel for the uses switch from spectroscopic mode to imaging mode easily. Our device is compact and light weighted while it provides a decent resolving power. We produce monolithic grisms using e-beam lithography at the NASA JPL and chemically etching the grooves on the silicon prisms. Moreover, the main-disperser and cross-disperser will be contacted together by direct Si-Si bonding technique and eventually turn into one piece. The bonded pair offers more stability in terms of the layout of the spectrum and removes the Fresnel loss at the intersection of two grisms. We report on the proper wafer bonding steps through this research, and inspected the bonding quality thermally, optically and mechanically.

• 한국세라믹학회지
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• 제39권12호
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• pp.1158-1163
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• 2002

2차 비선형 광특성을 유도하기 위한 UV 폴링용 Ge와 B가 첨가된 광민감성 광섬유를 제조하였다. 248 nm KrF 엑시머 레이저 조사에 의하여 수소처리 없이 장주기 격자를 형성할 수 있었다. 116 mJ/$cm^2$의 펄스 에너지와 10 Hz의 조사 빈도로 1분간 광민감성 광섬유에 레이저를 조사할 경우 -4 dB의 큰 band rejection 특성을 얻을 수 있었다. 제조된 광섬유의 광민감성은 장주기 격자쌍 방법을 이용하여 측정하였으며, 8.67 kJ/$cm^2$의 fluence로 KrF 엑시머 레이저를 조사할 경우 3.3${\times}10^{-3}$의 큰 코어 굴절률 변화를 얻었다. 또한 UV 폴링 시에 광섬유 코어에 고전압을 쉽게 인가할 수 있는 H자 형상의 광섬유를 인출조건의 최적호를 통하여 제조하였다.

• 한국전기전자재료학회논문지
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• 제27권12호
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• pp.831-836
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• 2014

One-dimensional (1D) photonic crystals (PCs) were prepared by $TeO_x(2&lt;x&lt;3)/SiO_2$ with the difference refractive index, and fabricated by sputtering technique from a $TeO_2$ and $SiO_2$ target. The $TeO_x$(2$Ar:O_2=40:10$). A 10-pair $TeO_x(2&lt;x&lt;3)/SiO_2$ 1D PCs were fabricated with the structure parameters of filling factor=0.5185, and period=410 nm. The properties of 1D PCs with and without a defect layer were evaluated by UV-VIS-NIR. A normal mode 1D PC have a photonic band gap (PBG) in the near infrared (NIR) region from 1,203 to 1,421 nm. In the case of 1D PC containing a defect layer, a defect level appears at 1,291 nm. The measured transmittance (T) spectra are nearly corresponding to calculated results. After He-Cd laser exposure, the defect level is shifted from 1,291 nm to 1,304 nm.

• Journal of Nutrition and Health
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• 제33권5호
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• pp.517-523
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• 2000

The effect of dietary zinc deficiency and age on lipid peroxide level was investigaed in rats. Zinc level in serum and liver were also measured. Fifty Sprague-Dawly male rats aging 8 months(older rats) and 2 months(younger rats) were used as experimental animal. Zinc deficient diet(1.1ppm) and normal zinc diet(36.5ppm) were used as experimental diets. Rats in each age group were divided into zinc deficient(ZnDF), zinc pair-fed(ZnPF) and zinc ad-libitum(ZnAL) to remove the variances of food intake. After 4 weeks of experimetal period, rats were sacrificed. Thiobarbituric acid reactive substance(TBARS) levels in plasma and liver, lipofuscin and conjugated diene levels in liver were measured as lipid peroxide index. Food intakes of all groups were not different because zinc deficiency did not reduce food intake in ZnDF group. Younger rats gained weight continuously, while older rats lost weight in the begining of experiment and regained afterwards. In older rats, serum zinc level was decreaed while plasma TBARS. level was increased in ZnDF group. In younger rats, plasma TBARS concentration was increased in dietary zinc deficient rats although serum zinc concentration was not reduced. Liver zinc concentration was significantly higher in older rats comparing to younger rats. However, there was no difference among the three dietary groups. Liver TBARS level was not different by age or dietary zinc level. However it was tended to be higher in older rats. However there was no difference by the dietary zinc level. In both age groups, ZnDF group significantly increased plasma TBARS levels, which suggested dietary zinc deficiency could increase lipid peroxidation in part. Significantly higher levels of lipofuscin and conjugated diene in older rats suggested lipid peroxidation was accelerated by aging.

• 한국패류학회지
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• 제22권1호
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• pp.39-49
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• 2006

Ultrastructure of germ cell differentiation during supermatogenesis and the reproductive cycle in male Patinopecten yessoensis was studied by histological and cytological observations. The gonadosomatic index (GSI) in males rapidly increased and reached a maximum in April when seawater temperature gradually increased. Then the GSI gradually decreased from May through July when spawning occurred. Accordingly, monthly changes in the GSI in males coincided with testicular maturation and spawning periods. The sperm morphology of P. yessoensis belongs to the primitive type and showed general characteristics of external fertilization species. The head of the spermatozoon is approximately $3.50{\mu}m$ in length: the sperm nucleus and acrosome are approximately $2.90{\mu}m\;and\;0.60{\mu}m$ in length, respectively. The nuclear type of the spermatozoon is vase in shape, and the acrosome is cone type. The axoneme of the tail flagellum consists of nine pairs of microtubules at the periphery and a pair of central microtubules in the center The satellite body (which is formed by the centriole) and four mitochondria appear in the middle piece of the spermatozoon. The spawning period was from April through July and the main spawning occurred from May to June when seawater temperatures gradually increased. The reproductive cycle of this species can be classified into five successive stages; early active stage (September to November), late active stage (October to March), ripe stage (February to August), spawning stage (April to July), and spent/inactive stage (July to November).

• Clinical and Experimental Pediatrics
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• 제65권1호
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• pp.35-46
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• 2022

Background: The growing prevalence of overweight and/or obese children is an important public health problem in both developed and developing countries. Although the association of obesity between parents and their children is well known, its underlying mechanisms are not well established. Purpose: This meta-analysis examined parent-child (PC) relationships in obesity and identified factors such as world region and country income level that may influence this relationship. Methods: We identified all related studies published between January 1, 2015 and May 31, 2020 by conducting a literature search using the MeSH terms "obesity," "overweight," "body mass index," "parent," "child," "associate," and "relate" in the PubMed database in English. Results: The meta-analysis of 23 studies that reported an odds ratio (OR) for parent and child obesity associations found a significant association between parents and children who were overweight or obese (pooled OR, 1.97; 95% confidence interval, 1.85-2.10). A meta-regression analysis was used to examine the sources of interstudy heterogeneity. The association between parent and child obesity was higher in Asia than in Europe and the Middle East and higher in high-income countries than in middle-or low-income countries. In addition, a higher association between parent and child obesity was found when both parents were obese than when only the father or mother was obese. This study from multiple countries indicates a significant PC relationship in weight status that varies according to PC pair type, parent and child weight statuses, world region, and country income level. Conclusion: These results demonstrate that the risk of childhood obesity is greatly influenced by parental weight status and indicate that parents could play an important role in preventing child obesity.

• 한국문헌정보학회지
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• 제57권4호
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• pp.311-331
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• 2023

본 연구는 2018년부터 2022년까지 5년간 국내 문헌정보학 분야의 주요 학술지 4종의 논문을 분석하여 지식 커뮤니케이션 특징을 탐구하고 중요한 연구 주제와 핵심 저자들을 분석하였다. 연구 방법으로 한국학술지인용색인(KCI)에서 국내 문헌정보학 분야의 핵심 학술지 4종의 5년간 발표된 논문을 수집하여 선별하여 논문의 저자 데이터와 참고문헌의 데이터를 추출하였다. Netminer를 사용하여 문헌동시인용 분석과 저자동시인용 분석을 실행하여 네트워크를 시각화하였다. 분석 결과, 저자 간의 동시인용 쌍을 도출할 수 있었으며, 연구자 간의 동시인용빈도 분석을 통해 학문 분야의 지적구조 분석에서 복수 저자를 분석 대상에 포함하는 것이 중요함을 확인하였다. 또한 키워드 분석을 통해 논문 주제 간의 상관성을 확인하였으며, 문헌정보학 관련 연구가 '도서관, 디지털, 이용자, 서비스, 데이터' 주제를 중심으로 이루어지고 있음을 알 수 있었다.