The Erythropeltidales are a common group of small, mostly epiphytic, marine red algae. However, they are little known in Korea. Many of the described species of Erythropeltidales differ subtly in morphology, and often the morphological differences are due to the substrate or environmental changes. Integration of molecular data with stan- dardized culture conditions has been recommended to account for these algae. A Madagascaria species was first collected from the western coast of Korea and was identified as Madagascaria erythrocladioides based on the morphological and molecular characteristics. Morphological characteristics conformed well with its original description, and the phylogenetic analysis based on rbcL sequence showed Korean M. erythrocladioides nests in the same clade with the original species described in Japan with a genetic distance of 0.0-0.1%. This species was isolated from a red alga, Pterocladiella capillacea, in laboratory culture. The thallus ontogeny and host preference were examined by a co-culture with 13 different species of algae. Results showed a relatively broad host preference in mono-spore attachment and epiphyte development of Madagascaria erythrocladioides. Mono-spores of M. erythrocladioides attached to most of the red algal hosts’ surfaces but no crustose thalli developed on some of the algal hosts even after one month of co-culture.

파킨슨병은 신경퇴행성질환으로 인지기능, 신경이상, 운동장애, 감각기능 장애를 보이게 된다. 감각기능 중 안구에도 다양한 증상이 나타나게 된다. 파킨슨병으로 발생할 수 있는 안구증상은 시력저하, 색각이상, 대비감도 저하, 눈 깜박임 감소, 안구 움직임 이상, 복시, 환각, 시야 결손 등으로 발생 할 수 있다. 특히, 색각이상 중 청록색 이상이 많았다. 또한, 눈 깜박임이 감소하며 깜박이는 시간이 길어져 안구건조가 발생할 수 있으며, 안구 움직임의 이상으로 폭주부족이 발생하기도 한다. 이로 인해 복시가 발생할 수 있고 환각이 나타나기도 한다. 녹내장과 관련이 있어 시야 이상이 발생하기도 한다. 약물치료와 함께 시력검사 및 전반적인 안구의 상태를 검진하고 꾸준한 관리가 필요할 것이다.

본 연구는 지카바이러스(ZIKV) 감염이 눈에 미치는 다양한 합병증을 제시하여 ZIKV 감염 예방의 중요성을 알리고자 연구하였다. ZIKV는 1952년 인체에서 처음 발견되었고, 2016년 브라질을 중심으로 남아메리카 대륙에서 폭발적인 감염을 일으키며 세계의 주목을 받게 되었다. ZIKV에 감염된 성인의 80%는 무증상 감염자이고 임산부를 통해 수직 감염되어 신생아에는 소두증 및 선천적 안구 장애를 합병증으로 가질 수 있음이 보고되었다. 눈은 고유의 혈액-망막 장벽을 가지고 안구를 보호하는 면역특권 기관이지만 바이러스 저장소 역할을 하여 ZIKV가 눈의 합병증을 유발한다는 최근의 학계 발표에 주목하고 있다. ZIKV의 감염 경로에 대해서는 활발히 연구 중이지만 지금까지는 백신이 없고 특별한 치료법이 없어 미리 예방하는 것만이 감염을 차단하는 유일한 방법이다. 특히, ZIKV 감염증은 태아 감염을 통한 잠재적 매개 변수를 가지는 더 위험성이 있기에 정부 당국과 지방 자치에서는 지속적 감시가 필요할 것으로 사료되어 이 논문을 제시한다.

목적 : 코로나19 팬데믹 기간 동안 젊은 성인을 대상으로 설문조사를 시행하여 스마트폰 사용 시간과 건성안 유병률 사이의 연관성을 평가하고자 하였다. 방법 : 대학생들을 대상으로 설문조사를 실시하였고 안구건조증은 OSDI 설문지를 이용하여 평가하였다. 안구 건조증은 OSDI 점수에 따라 경도(13~22), 중등도(23~32), 중증(33~100) 건성안으로 분류하였다. 결과 : 완성된 설문지는 총 282개를 받았지만, 기준에 맞지 않는 응답자를 제외하고 157개 설문지를 분석했다. 본 연구에서 코로나19 팬데믹 기간 동안 응답자의 77%가 스마트폰 사용 시간이 증가하였고, OSDI 을 통한 안구 건조 진단결과는 98명(62.4%)이 정상, 30명(19.1%)이 경도, 16명(10.2%)이 중등도, 13명(8.3%)이 중증인 건성안으로 밝혀졌다. OSDI는 스마트폰 사용시간 증가와 유의한 상관관계를 보였다(r=0.241, p=0.012). 결론 : 건성안 유병률은 157명 중 37.6%로 나타났고 안구건조증은 스마트폰 사용 시간의 증가와 관련이 있는 것으로 나타났다.

This study developed an analytical methodology for the mechanical integrity of spent nuclear fuel (SNF) cladding tubes under external pinch loads during transportation, with reference to the failure mode specified in the relevant guidelines. Special consideration was given to the degraded characteristics of SNF during dry storage, including oxide and hydride contents and orientations. The developed framework reflected a composite cladding model of elastic and plastic analysis approaches and correlation equations related to the mechanical parameters. The established models were employed for modeling the finite elements by coding their physical behaviors. A mechanical integrity evaluation of 14 × 14 PWR SNF was performed using this system. To ensure that the damage criteria met the applicable legal requirements, stress-strain analysis results were separated into elastic and plastic regions with the concept of strain energy, considering both normal and hypothetical accident conditions. Probabilistic procedures using Monte Carlo simulations and reliability evaluations were included. The evaluation results showed no probability of damage under the normal conditions, whereas there were small but considerably low probabilities under accident conditions. These results indicate that the proposed approach is a reliable predictor of SNF mechanical integrity.

목적 : 각막관련 수치가 안구의 새그높이에 미치는 영향과 어떠한 요소가 안구의 새그높이에 가장 큰 영향을 미치는지를 알아보고자 하였다. 방법 : 20, 30, 40, 50대의 건강한 240개의 눈을 대상으로 IOLMaster 700을 사용하여 전방깊이와 안구길이 를 측정하였고 Keratograph 4를 사용하여 각막중심곡률반경과 각막이심률을 측정하였고, KR-800을 사용하여 등가구면굴절력을 측정하였다. 각막 새그높이는 공식을 사용하여 계산하였다. 결과 : 각막 새그높이에 영향을 가장 크게 미치는 요소는 각막직경이었고 그 다음은 각막이심률이었다. 그리고 각막중심곡률반경이 가장 작은 영향을 미쳤다. 본 연구에서 0.10 mm 정도의 각막 새그높이 변화는 각막직경 0.20 mm 그리고 각막이심률 0.05~0.10의 변화에 상응하는 것으로 나타났다. 결론 : 소프트 콘택트렌즈 피팅이 콘택트렌즈의 새그깊이와 각막의 새그높이 관계에 의해 영향을 크게 받는다면 각막직경 및 각막이심률의 측정은 콘택트렌즈의 변수를 선택하는데 있어서 적절한 방법으로 생각된다. 더불어 각막 새그높이와 각막직경 및 각막이심률과의 수치 관계는 소프트 콘택트렌즈 피팅을 위한 추가적인 정보로 활용 될 수 있으리라 생각된다.

Two linyphiid spiders, Saitonia kawaguchikonis Saito & Ono, 2001 and Asthenargus niphonius Saito & Ono, 2001 were confirmed from Korea for the first time. Males of S. kawaguchikonis and a female of A. niphonius were collected with pitfall traps in a leaf litter of mixed forests in three National Parks (Hallyeohaesang National Park, Mt. Naejangsan, and Mt. Sobaeksan) during the seasonal surveys for the spider fauna in mountainous terrain from 2018 to 2020. These two species were formerly known from China and Japan, or only from Japan, respectively. The present study describes these two species with measurements, morphological illustrations, and a distribution map. This report adds the genus Asthenargus Simon & Fage, 1922 from Korea to the Korean spider fauna for the first time.

A laser scabbling experiment was performed using a high-power fiber laser to investigate the removal rate of the concrete block and the scabbled depth. Concrete specimens with a 28-day compressive strength of 30 MPa were used in this study. Initially, we conducted the scabbling experiment under a stationary laser beam condition to determine the optimum scan speed. The laser interaction time with the concrete surface varied between 3 s and 40 s. The degree of spalling and vitrification on the surface was primarily dependent on the laser interaction time and beam power. Furthermore, thermal images were captured to investigate the spatial and temporal distribution of temperature during the scabbling process. Based on the experimental results, the scan speed at which the optical head moved over the concrete was set to be 300 mm∙min−1 or 600 mm∙min−1 for the 4.8-kW or 6.8-kW laser beam, respectively. The spalling rates and average depth on the concrete blocks were measured to be 87 cm3∙min−1 or 227 cm3∙min−1 and 6.9 mm or 9.8 mm with the 4.8-kW or 6.8-kW laser beams, respectively.

목적 : 라식수술 후 고위수차에 영향을 미치는 요인을 분석하였다. 방법 : 기존의 라식수술을 받은 42안(23.43±2.06세)을 대상으로 하였고, 눈의 고위수차는 파면수차계를 이용하여 측정하였다. 라식수술안의 고위수차에 대한 모든 독립변수들의 기여도는 단순선형회귀분석과 다중회귀분석을 이용하여 평가하였다. LASIK 대상자의 전체고위수차에 영향을 미치는 요인을 평가하기 위해 후진선택방법의 다중회귀분석이 사용되었다. 결과 : 라식수술 대상자에서 전체고위수차의 RMS 값은 4 mm 동공에서 0.121±0.050, 6 mm 동공에서는 0.570±0.260였다. 다중회귀분석에서 4 mm 동공의 전체고위수차와 관련 있는 변수는 각막절제직경과 OSI이었고, 6 mm 동공에서 전체고위수차와 관련 있는 변수는 각막두께, 각막절삭량, 각막절제직경, LCVA(photopic), HCVA(mesopic), MTF cutoff 등으로 나타났다. 최종 다중회귀모델에서, 4 mm 동공의 전체고위수차에 유의하 게(p<0.050) 영향을 미치는 변수는 OSI(p=0.036)로 나타났고, 6 mm 동공의 전체고위수차에 유의하게 영향을 미치는 변수는 각막절삭량(p=0.016), HCVA(mesopic)(p=0.002), MTF cutoff(p=0.039) 등으로 나타났다. 결론 : 본 연구의 결과는 라식수술 후 변화된 각막형상으로 증가된 고위수차가 눈의 광학적 시스템에 영향을 미치면서 시력의 질에 영향을 줄 수 있음을 시사한다.

Project Management Information System (PMIS) is a special purpose information system that is created to provide useful information for project managers and participants to make effective and efficient decision making during projects. The use of PMIS is increasing in project based industries such as construction, defense, manufacturing, software development, telecommunication, etc. It is generally known that PMIS helps to improve the quality of decision making in project management, and consequently improves the project management performance. However, it is unclear what are the difference of PMIS impacts between industries, and still need to be studied further. The purpose of this study is to compare the impact of PMIS on project management performance between industries. We assume that the effects of PMIS will be different depending on the industry types. Five hypotheses are established and tested by using statistical methods. Data were collected by using a survey questionnaire from those people who had experience of using PMIS in various project related industries such as construction, defense, manufacturing, software development and telecommunication. The survey questionnaire consists of 5 point scale items and were distributed through e-mails and google drive network. A total of 181 responses were collected, and 137 were used for analysis after excluding those responses with missing items. Statistical techniques such as factor analysis and multiple regression are used to analyze the data. Summarizing the results, it is found that the impacts of PMIS quality on the PM performance are different depending on the industry types where PMIS is used. System quality seems to be more important for improving the PM performance in construction industry while information quality seems more important for manufacturing industry. As for the ICT and R&D industries, PMIS seems to have relatively lesser impact compared to construction and manufacturing industries.

목적 : 수치 해석을 통해 Gullstrand 모형안에서 광학적 특성(초점거리, 구면수차 및 초점심도)를 분석했다. 방법 : 광학상수 값(방수)이 수정된 Gullstrand 모형안(각막 전·후면, 수정체 피질 전·후면 및 수정체 핵질 전·후면)을 사용하였다. 평행광선이 입사되었을 때 근축 근사 없는 Snell의 법칙에 따른 눈의 광학적 특성을 수치적으로 분석하였다. 결과 : 모형안으로 입사된 모든 평행광선은 입사 높이가 증가할수록 초점거리, 구면수차 및 초점심도에서 각각 비선형적으로 감소, 증가 및 감소한 것으로 나타났으며, 일반적으로 알려진 근축 근사가 적용된 Gullstrand 정식 모형안의 결과와 잘 일치되었다. 결론 : 생체적 분석이 제한될 수밖에 없는 눈의 광학적 특성을 근축 근사 없이 수치적으로 분석할 수 있었다. 이를 기반으로 다양한 눈의 광학적 현상을 이해할 수 있을 것으로 판단된다.

목적 : 3D 시뮬레이션을 통해 구현된 Gullstrand 모형안에서 눈의 광학적 특성을 분석하였다. 방법 : 시뮬레이션 프로그램인 SPEOS를 이용하여 Gullstrand 모형안을 모델링하였다. 결과 : 모델링된 모형안으로 입사된 평행광선은 모두 망막 앞에 결상하는 것으로 나타났으며, 이는 근사 없이 계산한 결과 및 일반적으로 잘 알려진 결과와 일치하였다. 평행광선의 입사 높이에 따른 초점심도를 분석한 결과 입사 높이에 따라 지수 함수 형태로 급격히 감소하였다. 또한 구면수차는 입사광선의 높이에 따라 비선형적으로 증가하였다. 결론 : 본 연구와 같이 생체적으로 접근이 어려운 눈의 광학적 현상은 시뮬레이션에 따른 결과 분석을 통해 이 해도를 좀 더 높일 수 있고, 눈의 다양한 광학적 현상에 적용될 수 있을 것으로 판단된다.

Recently, environmental DNA (eDNA)-based metabarcoding approaches have been proposed to evaluate the status of freshwater ecosystems owing to various advantages, including fast and easy sampling and minimal habitat disruption from sampling. Therefore, as a case study, we applied eDNA metabarcoding techniques to evaluate the effects of an abandoned mine land located near a headwater stream of Nakdonggang River, South Korea, by examining benthic macroinvertebrate diversity and compared the results with those obtained using the traditional Surber-net sampling method. The number of genera was higher in Surbernet sampling (29) than in the eDNA analysis (20). The genus richness tended to decrease from headwater to downstream in eDNA analysis, whereas richness tended to decrease at sites with acid-sulfated sediment areas using Surber-net sampling. Through cluster analysis and non-metric multidimensional scaling, the sampling sites were differentiated into two parts: acid-sulfated and other sites using Surber-net sampling, whereas they were grouped into the two lowest downstream and other sites using eDNA sampling. To evaluate freshwater ecosystems using eDNA analysis in practical applications, it is necessary to constantly upgrade the methodologies and compare the data with field survey methods.

Recently, the number and scale of projects being carried out within the enterprise are increasing. Accordingly, many companies are competitively introducing a Project Management Office (PMO) to efficiently manage these projects, allocate resources, and effectively link the projects and corporate strategies. However, the project manager who directly manages the project wants to receive support from the PMO in many areas for successful project management, but the project manager does not like to be interfered with by the PMO. On the other hand, the PMO may not be able to satisfy all the requirements of each PM as PMO oversees the entire project with limited resources. In addition, since the PMO must monitor and control the project and support the project according to the priorities of each project, conflicts with each PM can be formed. Therefore, in this study, based on the case of a company, the difference between the perceptions of PMs and PMOs about the importance of the required roles of PMOs is to be examined. As a result of the study, it was confirmed that the core functions and sub-functions of PMO, which PMO members and PMs consider important, are different. It was identified that the PMs valued the PMO function that would be helpful for their successful project execution. On the other hand, PMO members revealed that they had a relatively high priority for the roles to monitor and control project performance for which they were directly responsible.

Non-face-to-face lectures have become a necessity rather than an option since COVID-19, and in order to improve the quality of university education, it is necessary to explore the properties of non-face-to-face lectures and make active efforts to improve them. This study, focusing on this, aims to provide basic data necessary for decision-making for non-face-to-face lecture design by analyzing the relative importance and execution satisfaction of non-face-to-face lecture attributes for professors and students. Based on previous research, a questionnaire was constructed by deriving 4 factors from 1st layer and 17 from 2nd layer attributes of non-face-to-face lectures. A total of 180 valid samples were used for analysis, including 60 professors and 120 students. The importance of the non-face-to-face lecture properties was calculated by obtaining the weights for each stratified element through AHP(Analytic Hierachy Process) analysis, and performance satisfaction was calculated through statistical analysis based on the Likert 5-point scale. As a result of the AHP analysis, both the professor group and the student group had the same priority for the first tier factors, but there was a difference in the priorities between the second tier factors, so it seems necessary to discuss this. As a result of the IPA(Importance Performance Analysis) analysis, the professor group selected the level of interaction as an area to focus on, and it was confirmed that research and investment in teaching methods for smooth interaction are necessary. The student group was able to confirm that it is urgent to improve and invest in the current situation so that the system can be operated stably by selecting the system stability. This study uses AHP analysis for professors and students groups to derive relative importance and priority, and calculates the IPA matrix using IPA analysis to establish the basis for decision-making on future face-to-face and non-face-to-face lecture design and revision. It is meaningful that it was presented.

The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.

In this study, using the concept of perezhivanie as an analytical tool, we were trying out new ways to investigate L2 identity taking the peripheral educational context into account. We examined how two graduates from non-academic high schools perceived their peripheral school situation through their perezhivanie, and described how this situation affected the individual trajectories of L2 identity development as well. When two students immersed themselves in marginalized classroom contexts, they have experienced academic stigma in the context of classroom community. Moreover, they all experienced emotional conflicts related to English learning. Besides, they struggled over deficit remedial L2 identity, entailing identity tensions. As they attempted to reconcile the contradictions between themselves and their circumstances, their perezhivanie made their social situation of development differently. Depending on how the contradiction was being emotionally experienced through the prism of each student’s perezhivanie, the same contradiction had different meanings, led to different reactions, and had differing impacts on their L2 identity.

This study was conducted to estimate the effect of different cutting lengths on fermentation characteristics and aerobic stability of whole crop rice (WCR) silage. The WCR was harvested at the yellow ripe stage (43.7%, DM), and then cut at 5 (R05), 10 (R10), and 20 cm (R20) of the theoretical length of cut with no cut WCR (R60). Each forage was ensiled into 20 L mini bucket silo (5 kg) for 150 days in quadruplicates. The cutting lengths were not affected the chemical compositions of WCR silage (p > 0.05). The pH (p < 0.001) and concentration of ammonia-N (p = 0.022) in WCR silage were increased linearly with the increase of cutting length. The concentration of lactate had quadratic effect (p = 0.007), which was highest in R20 silage (p < 0.05). The concentration of acetate was increased linearly (p = 0.014), but the concentration of butyrate was decreased linearly (p = 0.033). The lactic acid bacteria count was decreased linearly (p = 0.017), and yeast count had quadratic effect (p = 0.009), which was the highest in R20 silage (p < 0.05). Aerobic stability had strong quadratic effect (p < 0.001), which was the highest in R20 silage (p < 0.05). In conclusion, R60 silage had highest pH by a linear increase of ammonia-N concentration and led to low aerobic stability. While R20 silage had the lowest pH by high lactate concentration and led to high aerobic stability.

Cutting management has been identified as a critical factor in the alfalfa production systems because it has a significant impact on maximizing yield and maintaining the forage quality. The objective of this experiment was to determine the proper cutting height according to harvesting time for optimizing nutrient yield and forage nutritive quality of alfalfa grown in alpine regions of Korea. Alfalfa was sown at a seeding rate of 30 kg/ha in August 2018 and harvested at four cuttings in 2019 (3 May, 2 July, 11 September, and 13 October). Cutting heights were adjusted at 5, 15, and 25 cm above the soil surface. Alfalfa plant was tallest at the third cutting (109 cm), which was on average 35 cm taller than the first or second cutting. Relative feed value (RFV) remained unaffected by cutting height at the first harvest, but increased consistently in subsequent harvests as cutting height increased. Alfalfa collected at the first and fourth cuttings had the highest RFV (mean 152), which was on average 8 and 67 units higher than the second and third harvests, respectively. At each harvest, in vitro dry matter digestibility was highest in alfalfa cut at a 25-cm height. Dry matter (DM) production at each cutting height was highest in the first cutting, accounting for on average 36-37% of total annual DM production, and lowest in the fourth harvest, accounting for about 11-13% of the total DM yield. The total dry matter production (in four harvests) was 4,218 kg/ha higher when alfalfa was subjected to a cutting height of 5 cm rather than 25 cm. Cutting height had no effect on total crude protein yield, but from the first to fourth cutting, the protein yield followed a decreasing trend. Finally, there were visible declines in forage nutritive quality when alfalfa was cut at a shorter height. However, the magnitude of difference in total forage yield may outweigh the slight decline in forage quality when alfalfa is cut at a lower height. The findings of this study could help the alfalfa growers make better harvest management decisions.