• Wind and Structures
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• 제12권3호
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• pp.239-257
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• 2009

This paper develops and discusses a method by which it is possible to evaluate the Equivalent Static Force (ESF) of wind in the case of long-span bridges. Attention is focused on the alongwind direction. The study herein carried out deals with the classical problems of determining the maximum effects due to the alongwind action and the corresponding ESFs. The mean value of the maximum alongwind displacement of the deck is firstly obtained both by the spectral analysis and the Gust Response Factor (GRF) technique. Successively, in order to derive the other wind-induced effects acting on the deck, the Gust Effect Factor (GEF) technique is extended to long-span bridges. By adopting the GRF technique, it is possible to define the ESF that applied on the structure produces the maximum alongwind displacement. Nevertheless the application of the ESF so obtained does not furnish the correct maximum values of other wind-induced effects acting on the deck such as bending moments or shears. Based on this observation, a new technique is proposed which allows to define an ESF able to simultaneously reproduce the maximum alongwind effects of the bridge deck. The proposed technique is based on the GEF and the POD techniques and represents a valid instrument of research for the understanding of the wind excitation mechanism.

• Smart Structures and Systems
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• 제14권4호
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• pp.569-594
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• 2014

Damage detection methods based on modal analysis have been widely studied in recent years. However the calculation of mode shapes in real structures can be time consuming and often requires dedicated software programmes. In the present paper the combined application of proper orthogonal decomposition and gapped smoothing method to structural damage detection is presented. The first is used to calculate the dynamic shapes of a damaged structural element using only the time response of the system while the second is used to derive a reference baseline to which compare the data coming from the damaged structure. Experimental verification is provided for a beam case while numerical analyses are conducted on plates. The introduction of a stiffener on a plate is investigated and a method to distinguish its influence from that of a defect is presented. Results highlight that the derivatives of the proper orthogonal modes are more effective damage indices than the modes themselves and that they can be used in damage detection when only data from the damaged structure are available. Furthermore the stiffened plate case shows how the simple use of the curvature is not sufficient when analysing complex components. The combined application of the two techniques provides a possible improvement in damage detection of typical aeronautical structures.

• Journal of Ship and Ocean Technology
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• 제6권1호
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• pp.27-33
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• 2002

Recently, the application of the electric propulsion system becomes popular because of its advantage over conventional propulsion. However, the complicated flow mechanism and interaction around the azimuth thruster are not fully understood yet, and the studies on the powering performance characteristics with azimuth/pod thrusters are now in progress. The experimental method developed in KRISO(Korea Research Institute of Ships & Ocean Engineering) is introduced and the results of the powering performance tests, consisting of resistance, self-propulsion and propeller open water tests for a cable layer with two azimuth thrusters are presented. For the analysis of powering performance with azimuth thrusters, it is necessary to evaluate the thrust/drag for components of a thruster unit, Extrapolation results could differ according to the various definitions of the propulsion unit; that is the pod, thruster leg and/or nozzle can be treated as hull appendages or as part of propulsion unit, The powering performances based on several definitions are investigated for this vessel. The results of the measurements for the 3-dimensional velocity distribution on the propeller plane are presented to understand the basis of the difference in propulsion characteristics due to the propeller rotational directions.

• Journal of Astronomy and Space Sciences
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• 제30권4호
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• pp.269-277
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• 2013

In this study, we present results of precise orbital geodetic parameter estimation using satellite laser ranging (SLR) observations for the International Laser Ranging Service (ILRS) associate analysis center (AAC). Using normal point observations of LAGEOS-1, LAGEOS-2, ETALON-1, and ETALON-2 in SLR consolidated laser ranging data format, the NASA/GSFC GEODYN II and SOLVE software programs were utilized for precise orbit determination (POD) and finding solutions of a terrestrial reference frame (TRF) and Earth orientation parameters (EOPs). For POD, a weekly-based orbit determination strategy was employed to process SLR observations taken from 20 weeks in 2013. For solutions of TRF and EOPs, loosely constrained scheme was used to integrate POD results of four geodetic SLR satellites. The coordinates of 11 ILRS core sites were determined and daily polar motion and polar motion rates were estimated. The root mean square (RMS) value of post-fit residuals was used for orbit quality assessment, and both the stability of TRF and the precision of EOPs by external comparison were analyzed for verification of our solutions. Results of post-fit residuals show that the RMS of the orbits of LAGEOS-1 and LAGEOS-2 are 1.20 and 1.12 cm, and those of ETALON-1 and ETALON-2 are 1.02 and 1.11 cm, respectively. The stability analysis of TRF shows that the mean value of 3D stability of the coordinates of 11 ILRS core sites is 7.0 mm. An external comparison, with respect to International Earth rotation and Reference systems Service (IERS) 08 C04 results, shows that standard deviations of polar motion $X_P$ and $Y_P$ are 0.754 milliarcseconds (mas) and 0.576 mas, respectively. Our results of precise orbital and geodetic parameter estimation are reasonable and help advance research at ILRS AAC.

• 한국응용곤충학회지
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• 제25권1호
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• pp.53-61
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• 1986

콩씨스트선충(線蟲)에 대(對)한 저항성품종육성(抵抗性品種育成)을 위하여 경북, 충북, 전남 3 개도 13지역(地域)에서 콩씨스트선충(線蟲)의 race를 조사(調査)한 결과(結果), Race 1 이 1계통(系統) Race c가 1계통(系統) 그리고 Race 5가 11계통(系統)으로 우리나라에서는 Race 5가 우점 race임을 알 수 있었다. 콩씨스트선충(線蟲) Race 5에 대(對)한 재래종(在來種)콩 203계통(系統)에 대(對)하여 포장저항성검정결과(圃場抵抗性檢定結果) 재래종(在來種)은 계통번호(系統番號) 18, 21, 36, 38, 41, 42, 43, 45, 55, 59, 68, 72, 75, 79, 93, 94, 95, 98, 123, 131, 136, 146, 170, 174, 187, 190, 191 등 27 계통(系統)이 한뿌리당 씨스트의 수(數)가 10 개미만으로써 다른 계통(系統)에 비(比)하여 적게 증식(增植)되었고, 나머지 176계통(系統)은 많이 증식(增殖)되었다. 포장실험(圃場實驗)에서 비교적(比較的) 선충(線蟲)의 증식(增殖)이 적게된 27 계통(系統)을 선발(選拔)하여 Pot에서 재검사(再檢査)를 한 결과(結果) 계통번호(系統番號) 170(음성군, 조촌리(陰城那, 助村里)) 번이 한 주(株)당 씨스트의 수(數)가 10개로 중정도(中程度)의 저항성(抵抗性)을 나타냈고 계통번호(系統番號) 55(영풍군, 내림리(榮豊那, 內林里))번은 다른 계통(系統)에 비(比)하여 다소 선충(線蟲)의 증식(增殖)이 적게 되었으나 나머지 25계통(系統)은 모두 30개이상(個以上)으로 많이 증식(增植)되어 감수성(感受性)을 나타냈다. 그리고 도입품종(導入品種) 25종중(種中)에서는 Peking, IIlsoy, PI90763 등 3품종(品種)은 포장(圃場)과 Pot실험(實驗)에서 다같이 선충(線蟲)의 증식(增殖)이 전혀 되지않는 저항성(抵抗性)으로 나타났고 Custer. Delmar, Dyer, Jackson 등 4품종(品種)은 씨스트의 수가 10개미만으로 비교(比較的) 적게 증식(增殖)되어 중정도(中程度)의 저항성(抵抗性)을 나타냈으나 나머지 18품종(品種)은 감수성(感受性)을 나타냈다. 수량성(收量性)을 검사(檢査)한 재래종중(在來種中)에서는 계통번호(系統番號) 170번이 역시 주당분지수, 주당협수 주당협중, 100립에 있어서 무감염구(無感染區)에 비(比)하여 감수율(減收率)이 각각(各各) 0%, 1.8%, 1.2%, 1.7% 로서 외국(外國)에서 저항성품종(抵抗性品種)으로 알려진 Peking, PI90763 과 같은 경향을 나타냈다. 그리고 계통번호(系統番號) 55, 75, 187번은 다른 계통(系統)에 비(比)하여 다소 낮은 감소율(減少率)을 나타냈다. 도입종중(導入種中)에는 Peking 과 PI90763 이 주당분지수 주당협수, 주당협중 및 100립중에서 모두 1.6% 이하의 낮은 감소율(減少率)을 나타냈으나 Illsoy 는 주당협수와 주당협중에서 3.8% 및 3.4%의 다소 높은 감소율(減少率)을 나타낸 한편 Custer, Delmar, Dyer, Jackson 등은 비교적 감소율이 높게 나타났다.

• Journal of Biosystems Engineering
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• 제34권2호
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• pp.114-119
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• 2009

Field test was conducted to investigate primary factors reducing rapeseed harvesting using a reciprocating cutter-bar of combine. The results showed that the correlation between crop moisture content and yield loss had a U-type, which indicated that the yield reduction increased at too high and too low crop moisture contents. The proper ranges of crop moisture contents were 27${\sim}$35%, 21${\sim}$56%, and 62${\sim}$73% in case of grain, pod and stem, respectively. Crop moisture content was negatively correlated with header loss, but positively correlated with threshing loss. In contrary, stem moisture content showed positive correlations with total loss, threshing loss and separation loss. Working speed was positively correlated with header loss. Total flow rate, pod flow rate and stem flow rate were highly correlated with threshing loss and separation loss. However, grain flow rate did not show any correlation with total loss. According to the principal component analysis, two principal components were derived as components with eigenvalues greater than 1.0. The contribution rates of the first and the second components were 52.7% and 38.9%, which accounted for 91.6% of total variance. As a contributive factor influencing total loss of rapeseed mechanical harvesting, a crop moisture content factor was greater than a crop flow rate factor. The stepwise multiple regression analysis for total loss was conducted using crop moisture content factor, crop flow rate factor and coefficient. However, the model did not show any correlation among independent and dependent factors ($R^2$=0.060).

• Journal of Korean Neurosurgical Society
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• 제65권6호
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• pp.834-840
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• 2022

Objective : C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count are inflammatory markers used to evaluate postoperative infections. Although these markers are non-specific, understanding their normal kinetics after surgery may be helpful in the early detection of postoperative infections. To compliment the recent trend of reducing the duration of antibiotic use, this retrospective study investigated the inflammatory markers of patients who had received antibiotics within 24 hours after surgery according to the Health Insurance Review & Assessment Service guidelines and compared them with those of patients who had received antibiotics for 5 days, which was proven to be non-infectious. Methods : We enrolled 74 patients, divided into two groups. Patients underwent posterior lumbar interbody fusion (PLIF) at a single institution between 2019 and 2020. Group A included 37 patients who received antibiotics within 24 hours after the PLIF procedure, and group B comprised 37 patients who had used antibiotics for 5 days. A 1 : 1 nearest-neighbor propensity-matched analysis was used. The clinical variables included age, sex, medical history, body mass index, estimated blood loss, and operation time. Laboratory data included CRP, ESR, and WBC, which were measured preoperatively and on postoperative days (POD) 1, 3, 5, and 7. Results : CRP dynamics tended to decrease after peaking on POD 3, with a similar trend in both groups. The average CRP level in group B was slightly higher than that in group A; however, the difference was not statistically significant. Multiple linear regression analysis revealed operation time, number of fused levels, and estimated blood loss as significant predictors of a greater CRP peak value (r²=0.473, p<0.001) in patients. No trend (a tendency to decrease from the peak value) could be determined for ESR and WBC count on POD 7. Conclusion : Although slight differences were observed in numerical values and kinetics, sequential changes in inflammatory markers according to the duration of antibiotic administration showed similar patterns. Knowledge of CRP kinetics allows the assessment of the degree of difference between the clinical and expected values.

• 한국작물학회지
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• 제46권2호
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• pp.89-94
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• 2001

Sword bean belongs to the subgenus Canavalia in the genus Canavalia. White and reddish varieties in sword bean were tested to obtain the basic information for improving the yield, quality, and cultural environments through the quantitative growth analysis. Growing plants were sampled at intervals of 10 days from 20 days after sowing. Whole plant weight increased during the period of 11-20 days after sowing in both varieties. The weight of each organ between two varieties increased similarly except leaf area. Whole plant weight changed more close to pod weight than any other characters. The leaf areas of both varieties increased from 50 days after sowing, var. white displayed S type curved line but var. reddish displayed slow S type curved line. The SGR of whole plant weight in both varieties had 3 maxima and 2 minima, 3 maxima and first minimum were shown at the same period but the second minimum was shown at different period. Both varieties showed bimodal curved line. All SGR of each organ and leaf area were shown the 2 maxima and 1 minimum in both varieties. The changes of SLA and LAR were not remarkable between two varieties but these were united together with the maximum of whole plant weight and root weight. ULWR and ULWR were shown similar in both varieties. Reddish variety was more prosperous in early growth stage than white variety because SLA, LAR and LWR were high. In surplus weight, both varieties increased rapidly during the period of 111-120 days after sowing that was applicable to the maximum SGR of pod weight. Surplus weight of var. white increased markedly during the same period comparing those of var. reddish.

• 조명전기설비학회논문지
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• 제27권11호
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• pp.82-88
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• 2013

It is important to give lightning warning prior to a cloud-to-ground (CG) discharge within an Area of Concern (AOC) because most of lightning damage and victim are usually occurred by the first lightning in the AOC. The aim of this study is to find the optimal operation conditions of the automated lightning warning systems in order to make the best use of the available data. In this paper, the test-operated results of the automated lightning alert and risk management system (ALARM) based on detections of CG discharge and eletrostatic field and optimized at probability of lightning have been described. It was possible to obtain the following warning performance parameters: probability of detection (POD), false alarm ratio (FAR), probability of lightning (POL) and failure-to-warn rate (FTW). The data obtained from trial operation for 5months were not sufficient but the first analysis of domestic lightning warning was carried out. We have observed that the evaluated statistical results through trial operation depend on the various factors such as analysis methods and criteria, topographical conditions, etc. Also we suggest some methods for improvement of POL and POD including the finding of the optimal electric field threshold level to be used, based on the high values of FAR and FTW found in this work.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.83-83
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• 2017

The National Agrobiodiversity Center (NAS, RDA, Republic of Korea) has continually collected new valuable genetic resources. In this study, we regenerated conserved kidney bean (Phaseolus vulgaris L.) germplasm which couldn't be available because of seed quantity and quality, and we also surveyed their morphological characters for the sustainable utilization. A total of 431 kidney bean accessions were regenerated and 18 morphological traits were surveyed according to the characterization guideline of RDA Genebank. Among the surveyed traits, flowering time ranged from May 23 to September 4 and 73.8% of tested accessions were mainly flowering in June. The maturity time ranged from July 1 to October 15 and main flowering time was July (91.4%). For plant type, 270 accs (62.6%) were climbing type followed by medium type of 86 accs (20.0%) and dwarf type of 65 accs (15.1%). The seed coat colors were various; yellow (34.6%), white (22.3%), brown (17.9%), red (10.7%), black (5.8%), violet (11%), pink (1.4%), navy (0.9%). Principal component analysis indicated that five principal components (PCs) with Eigen values >1 accounted for more than 65.8% variability. The first PC was more related to growth habits such as growth type, flowering time, and plant type. The second and third PCs showed higher values of the pigment characters such as seed coat color, flower color, and pod color. In fourth and fifty PCs, there were the higher positive values of the pod shapes. Our results provided insight into the characteristics kidney beans, thus the utilization basis of kidney beans might be elevated for bio-industry.