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Life Table Analysis of the Brown Planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae) on Rice of Resistant Cultivars (벼멸구 저항성 품종벼에서 벼멸구의 생명표 분석)

  • Choi, Nak Jung;Jeong, In-Hong;Kwon, Deok Ho;Choi, Man-Young;Baik, Chai-Hun
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.526-532
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    • 2017
  • Development, survival, and reproduction of brown planthopper (BPH) Nilaparvata lugens $St{\aa}l$ (Hemiptera: Delphacidae), were studied in laboratory at $25{\pm}2^{\circ}C$, $65{\pm}5%$ RH and a 16L : 8D hours photoperiodism on five rice cultivars of: Dongjin 1ho, Chungchungbyeo, Jangseongbyeo, Chinnongbyeo and Jungmo 1045. BPH nymphs successfully survived on all rice cultivars, although survival rate was lowest on Jangseongbyeo (36.0%). Developmental time of immature stages ranged from $11.7{\pm}0.59d$ on Jungmo 1045 to $12.8{\pm}0.59d$ on Chinnongbyeo. Reproductive period and female longevity were longest on Dongjin 1ho, Chinnongbyeo and Jungmo 1045 while highest fecundity of N. lugens being observed on these three rice cultivars. Highest and lowest net reproductive rates were calculated on rice cultivars, Jungmo 1045 and Jangseongbyeo, respectively. Mean generation time was the longest on rice cultivar Dongjin 1ho. Respective descending order of intrinsic rates of population increase were on Jungmo 1045, Chinnongbyeo, Dongjin 1ho, Chungchungbyeo and Jangseongbyeo. These population parameters showed that N. lugens can successfully survive and reproduce on Chinnongbyeo and Jungmo 1045.

The Growth of Cucumber and Variation of Soil Temperature Used by Warming Water Irrigation System (가온관수 시스템에 따른 지온변화와 오이의 생육)

  • 김태욱;김진현
    • Journal of Bio-Environment Control
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    • v.10 no.1
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    • pp.15-22
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    • 2001
  • A soil temperature was known as extremely important factor in terms of measuring the values of the growth and yield of vegetable in the greenhouse. A low temperature water irrigation was had much trouble in its growth. This study was performed to analyze the effect of the heating water irrigation on the soil temperature and the growth of a cucumber within a greenhouse environment. Soil temperature was 5-7$^{\circ}C$ below to 10cm in depth and 2-3$^{\circ}C$ to 20cm when the irrigation water temperature was 13$^{\circ}C$ (non-warme water irrigation). Soil temperature was similar to irrigation water temperature at 5cm in depth and was 1.5-2$^{\circ}C$ below at 10cm when the irrigation water temperatures were 2$0^{\circ}C$, $25^{\circ}C$. The early growth rates of heating water irrigation were 109-110% in plant height, 107-108% in leaf number, 103% in node number compared with those of unheated water irrigation for 30 days after planting it. The rates of total yield were 115% in 2$0^{\circ}C$ water irrigation plots and 121% in $25^{\circ}C$ water irrigation plots while those of unheated water irrigation plots were.

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Impact of Application Rate of Non-ionic Surfactant Mixture on Initial Wetting and Water Movement in Root Media and Growth of Hot Pepper Plug Seedlings (비이온계 계면활성제 혼합물의 처리농도가 상토의 수분 보유 및 고추 플러그묘의 생장에 미치는 영향)

  • Choi, Jong-Myung;Moon, Byung-Woo
    • Horticultural Science & Technology
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    • v.29 no.1
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    • pp.16-22
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    • 2011
  • In developing soil wetting agent using polyoxyethylene nonylphenyl ether (PNE) and polyoxyethylene castor oil (1:1; v/v), the effect of application rates on changes in concentration of PNE, initial wetting of peatmoss + perlite (7:3) medium, and growth of hot pepper (Capsicum annuum L. 'Knockwang') plug seedlings were investigated. The elevation of application rates of wetting agent increased the amount of water retained by the root media. The treatment of 2.5 $mL{\cdot}L^{-1}$ showed similar water retention to + control ($AquaGro^L$ 3.0 $mL{\cdot}L^{-1}$). Most of the liquid wetting agent (LWA) incorporated during the medium formulation leached out in the first and second irrigation, then it decreased gradually until 10 times in irrigation. In investigation of the influence of LWA on position of water infiltrating into root media, the vertical water movements in treatments of 0.5, 1.0, and 1.5 $mL{\cdot}L^{-1}$ were much faster than those in 0.0 $mL{\cdot}L^{-1}$ (-control), but relative speed of water movement decreased by the elevation in application rate of LWA to 2.0 or 2.5 $mL{\cdot}L^{-1}$. The evaporative water loss of root media that to contained various rate of LWA and irrigated to reach container capacity was the fastest in -control among the treatments and it delayed as the application rate of LWA was elevated. The plant height of 22.2 cm in 0.5 $mL{\cdot}L^{-1}$ and stem diameter of 3.26 mm in 1.0 $mL{\cdot}L^{-1}$ were the highest among the treatments tested. The treatment of 1.0 $mL{\cdot}L^{-1}$ also had the heaviest fresh and dry weights such among treatments tested as 3.08 g and 0.861 g per plant, respectively. The elevated application rate over than 1.5 $mL{\cdot}L^{-1}$ resulted in decreased seedling growth. The results mentioned above indicate that optimum application rate of LWA is 1.0 $mL{\cdot}L^{-1}$.

Adaptive Lock Escalation in Database Management Systems (데이타베이스 관리 시스템에서의 적응형 로크 상승)

  • Chang, Ji-Woong;Lee, Young-Koo;Whang, Kyu-Young;Yang, Jae-Heon
    • Journal of KIISE:Databases
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    • v.28 no.4
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    • pp.742-757
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    • 2001
  • Since database management systems(DBMSS) have limited lock resources, transactions requesting locks beyond the limit mutt be aborted. In the worst carte, if such transactions are aborted repeatedly, the DBMS can become paralyzed, i.e., transaction execute but cannot commit. Lock escalation is considered a solution to this problem. However, existing lock escalation methods do not provide a complete solution. In this paper, we prognose a new lock escalation method, adaptive lock escalation, that selves most of the problems. First, we propose a general model for lock escalation and present the concept of the unescalatable look, which is the major cause making the transactions to abort. Second, we propose the notions of semi lock escalation, lock blocking, and selective relief as the mechanisms to control the number of unescalatable locks. We then propose the adaptive lock escalation method using these notions. Adaptive lock escalation reduces needless aborts and guarantees that the DBMS is not paralyzed under excessive lock requests. It also allows graceful degradation of performance under those circumstances. Third, through extensive simulation, we show that adaptive lock escalation outperforms existing lock escalation methods. The results show that, compared to the existing methods, adaptive lock escalation reduces the number of aborts and the average response time, and increases the throughput to a great extent. Especially, it is shown that the number of concurrent transactions can be increased more than 16 ~256 fold. The contribution of this paper is significant in that it has formally analysed the role of lock escalation in lock resource management and identified the detailed underlying mechanisms. Existing lock escalation methods rely on users or system administrator to handle the problems of excessive lock requests. In contrast, adaptive lock escalation releases the users of this responsibility by providing graceful degradation and preventing system paralysis through automatic control of unescalatable locks Thus adaptive lock escalation can contribute to developing self-tuning: DBMSS that draw a lot of attention these days.

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Pain Reduction Effects of Lidocaine Gel for Urethral Catheterization : A Systematic Review and Meta-Analysis (요도 카테터 삽입술에서 리도카인 윤활제의 통증 감소 효과 : 체계적 문헌고찰과 메타분석)

  • Hong, Hyun-Jung;Kim, Ga-Eun;Lee, Ha-Nee;Lee, A-Reum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.438-448
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    • 2017
  • This study was a systematic review and meta-analysis that evaluated the results of research on the pain reduction effects of lidocaine gel for urethral catheterization in adults. A literature search was conducted using seven electronic databases, gray literature and other resources based on the guidelines of Preferred Reporting Items for Systematic review and Meta-Analysis (PRISMA). A Risk of Bias (RoB) tool was applied to assess the quality of selected studies. Data were analyzed using the RevMan 5.3.-program. Sixteen randomized controlled trials involving 1904 adults were included. RoB was not observed in the funnel plot. Overall, lidocaine gel was effective for pain reduction during urethral catheterization (Standard Mean Difference[SMD] -0.96;95% CI: -1.43, -0.49). To explore the cause of heterogeneity (I2=95%, p<.001), subgroup analysis was conducted according to three catheter types (urinary catheter, flexible cystoscopy, and rigid cystoscopy) and the SMDs were -0.88 (95% CI:-1.51, -0.26), -0.31 (95% CI:-0.63, 0.01), and -1.93 (95% CI:-2.88, -0.97), respectively. A significant pain reduction effect was observed regardless of gender in urinary catheterization. However, in rigid cystoscopy, a significant pain reduction effect was observed only in male subjects. Pain reduction effects were observed when 10~11ml lidocaine gel was used during rigid cystoscopy and when lubrication was used during urinary catheterization, irrespective of application time. These findings suggest that lidocaine gel is a useful anesthetic lubricant for urinary catheterization and rigid cystoscopy in male adults.

The effect of recapitalization on capital structure decision and corporate value in Korean Firms (한국기업의 자본재조정이 자본구조 의사결정과 기업가치에 미치는 영향분석)

  • Kim, Jooyul;Kim, Dongwook;Kim, Byounggon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.163-174
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    • 2017
  • This study analyzed how Korean firms' recapitalization affects their capital structure decision and firm value. Recapitalization was categorized into three groups according to the influence of the debt to equity ratio: debt ratio-increasing-recapitalization(capital reduction with refund, cash dividend), debt ratio-unchanging-recapitalization (capital reduction without refund, retirement of repurchased stocks), and debt ratio-decreasing-recapitalization(exercise the rights for convertible bonds, bond with stock warrants, exchangeable bonds and stock options). This article highlights how the relationship between the firms' recapitalization and the capital structure decision driven by the change in debt to equity ratio through the recapitalization should affect the firm value. The whole recapitalization sample used for this analysis comprised 22,814 enterprises listed on the Korea Exchange that were analyzed over the 16-year period from 2000 to 2015. To summarize the results of this Panel Data Analysis, firstly, when a firm executes debt ratio-increasing-recapitalization and debt ratio-decreasing-recapitalization at the period of t-1, the debt to equity ratio, which is increased or decreased, should affect the firm's debt capacity in the same period, then, at the period of t, the firm establishes a leverage policy to readjust the debt to equity ratio the other way around. These adjustments of debt-paying-ability from the leverage policy, including the capital structure decision, finally affect the firm value. Secondly, when a firm implements the debt ratio-unchanging-recapitalization in the period of t-1, the debt to equity ratio, which is neutral, should not affect the firm's capital structure decision. But, the firm value is positively affected by the influence of that recapitalization. Conclusively, we acknowledge a firm which carries out the recapitalization balances its capital structure to the optimal level of leverage and that the capital structure decision positively affects the corporate value.

Between-and Within-person Variability of Nutrient Intake in 7-day weighed Food Records (7일 실측법에 의한 영양소섭취량의 개인간변이와 개인내변이)

  • 정해랑
    • Journal of Nutrition and Health
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    • v.25 no.2
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    • pp.179-186
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    • 1992
  • Dietary intakes of 57 college women were measured by 7-day weight food records(7WR) Nutrient intakes of 7WR were compared with results of using 1-day weighted food records(1WR) and 2-day weighed food records(2WR), 7WR were recorded for 7 consecutive days by subjects and its first two days were chosen to provide 1WR and 2WR Mean nutrient intakes of the group were not significantly different between 1WR or 2WRand 7WR. Within-person variations were found to be greater than between-person variations. The ratio of within- and between-person variability was lowest for the vitamin A and highest for the calcium. Data on 7WR were analyzed to estimate the number of recording days needed to ensure r$\geq$0.9 between observed and turn mean intakes. The 11 to 13 days needed for energy sugar protein and vitamin A and 20 days for calcium The results indicated that the number of days needed varied substantially among individuals for the same nutrient and within individuals for different nutrients.

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The Analysis of the Need Rate of Shunt and the Outcome in Hydrocephalus Following SAH - Relationship between the Outcome and the Duration, Daily and Total Amount of CSF Drainage at EVD - (자발성 지주막하출혈 후 발생하는 수두증에 대한 단락술의 필요성 및 예후에 관한 분석 - 뇌실외배액술의 기간, 일일배액량 및 총배액량과 예후관계 -)

  • Lee, Won Chang;Choi, Chang Hwa
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup1
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    • pp.99-107
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    • 2001
  • Objective : Hydrocephalus and vasospasm are the common complications following subarachnoid hemorrhage (SAH). In spite of development of perioperative management and operative technique, hydrocephalus cause neurological deficit and poor prognosis. Usually CSF drainage procedure(external ventricular drainage(EVD) or shunt) is needed in hydrocephalus following SAH. The aim of this study was to investigate whether the need for shunting and the outcome after shunting in hydrocephaus following SAH can be related to the duration, daily and total amount of cerebrospinal fluid(CSF) drainage at EVD. Material and Method : IVH is one of several factors which cause hydrocephalus. In this retrospective study, firstly we investigated the incidence of IVH in total cases and frequency of IVH according to aneurysmal site and then prognosis of IVH following SAH. Among 629 patients with SAH, hydrocephalus was diagnosed by CT scan and symptoms. And then those 102 hydrocephalus following SAH were divided into two groups which were hydrocephalus with IVH group and without IVH group. In these two groups, we investigated and compared the incidence of hydrocephalus in all case, frequency of hydrocephalus according to aneurysmal site, the outcome according to H-H grade on admission and the need rate of shunt, etc. Of those hydrocephalus, 100 EVD procedures were done. The duration, daily and total amount of CSF drainage at EVD were investigated. Fifty cases expired during EVD was excluded. We analyzed whether the need rate of shunt and the final outcome after shunting can be related to IVH, the duration and daily and total amount of CSF drainage. Result : The incidence of hydrocephalus following SAH was 20%(with IVH group ; 64%, without IVH group ; 11%). As H-H grade on admission was better, the outcome of hydrocephalus was also better. The mortality rate of hydrocephalus with IVH was 64% which was higher than 40% that of hydrocephalus without IVH. The need rate of shunt in all cases of hydrocephalus following SAH was 20%, but those with IVH group excluding expired patients before shunt was 40%. This was very similar to 41% of the need rate of shunt in hydrocephalus without IVH. The total amount of CSF drainage was statistically related to the need rate of shunt(total amount : need rate of shunt/<1000cc : 15%, 1000-2000cc : 40%, >2000cc : 50%). The duration and daily amount of CSF drainage were not statistically related to the need rate of shunt, but as daily amount of CSF drainage was more and duration was longer, the need rate of shunt was increased(daily amount : need rate of shunt /<100cc : 16%, 100-200cc : 25%, >200cc : 40%//duration : need rate of shunt/<1week : 8%, 1-2weeks : 30%, >2weeks : 47%), and also the final outcome after shunting was poor. Especially the total amount of CSF drainage was significant related to the final outcome after shunting(total amount : GOS/<1000cc : I&II(3/4), 1000-2000cc : II(2/4), III(2/4), >2000cc : III&IV(6/7)). Conclusion : This study revealed that the incidence and mortality rate of hydrocephalus following SAH were influenced by IVH. So SAH associated IVH has the higher incidence of hydrocephalus and poor outcome. As the CSF drainage amount was more and duration of drainage was longer, the need rate of shunt was increased and the final outcome after shunting was poor. Especially the total amount of CSF drainage were strongly related to the need rate of shunt and the outcome after shunting.

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Comparison of the SNR in the MR images on dental implant material (치아 임플란트 재료에 따른 자기공명영상의 SNR 비교)

  • Kim, Dong-Hyun;Ko, Seong-Jin;Ye, Soo-Young
    • Journal of the Institute of Convergence Signal Processing
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    • v.16 no.4
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    • pp.149-155
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    • 2015
  • Tooth implant is located in oral cavity and affects neck, skull base, and facail image. These magnetic inhomogeneities are usually frequency encoding direction which cause artifacts due to change of signal strength and geometric distortion. First, to evaluate signal to noise ratio (SNR) of magnetic resonance image caused by tooth implant this study uses meat phantom which is similar to human body and is consisted with fat, muscle, and water to measure signal to noise ratio. Second, signal to noise ratio by using custom-made fixed phantom is measured, and then signal to noise ratio size of different tooth implant types is compared and analyzed. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for meat phantom were 2.76, 2.22, 1.88, and 1.57 on T1 SE, 1.88, 1.78, 1.65, and 1.79 on T2 FLAIR, 2.28, 2.25, 2.88, and 2.05 on T2 FSE, and 2.74, 1.94, 1.67, and 1.48 on T2 GRE. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for fixed water phantom were 1.2, 1.06, 1.12, and 1.22 on DWI, 1.93, 1.87, 1.93, and 2.06 T1 SE, 1.83, 1.76, 1.82, and 1.92 on T2 FLAIR, 1.85, 1.79, 7.86, and 1.97 on T2 FSE, and 1.97, 1.93, 1.99, and 2.06 on T2 GRE. By considering through the results, patients and dentists need to consider some impacts from testing many aspects although their main purpose of having tooth implants is a dental restoration. Moreover, depending on the tooth implant characteristics of individual patients this study results can be used as baseline data when choosing test protocol.

EFFECT OF ROTATIONAL SPEED OF PROTAPERTM ROTARY FILE ON THE CHANCE OF ROOT CANAL CONFIGURATION (ProTaperTM로 근관성형시 회전 속도 변화가 근관형태에 미치는 영향)

  • Seo, Min-Chul;Jeon, Yoon-Jeong;Kang, In-Chol;Kim, Dong-Jun;Hwang, Yun-Chan;Hwang, In-Nam;Oh, Won-Mann
    • Restorative Dentistry and Endodontics
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    • v.31 no.3
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    • pp.179-185
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    • 2006
  • This study was conducted to evaluate canal configuration after shaping by $ProTaper^{TM}$ with various rotational speed in J-shaped simulated resin canals. Forty simulated root canals were divided into 4 groups, and instrumented using by $ProTaper^{TM}$ at the rotational speed of 250, 300, 350 and 400 rpm. Pre-instrumented and post-instrumented images were taken by a scanner and those were superimposed. Outer canal width, inner canal width, total canal width, and amount of transportation from original axis were measured at 1, 2, 3, 4, 5, 6, 7 and 8 mm from apex. Instrumentation time, instrument deformation and fracture were recorded. Data were analyzed by means of one-way ANOVA followed by Scheffe's test. The results were as follows 1. Regardless of rotational speed, at the $1{\sim}2mm$ from the apex, axis of canal was transported to outer side of a curvature, and at 3~6 mm from the apex, to inner side of a curvature. Amounts of transportation from original axis were not sienifcantly different among experimental groups except at 5 and 6 mm from the apex. 2. Instrumentation time of 350 and 400 rpm was significantly less than that of 250 and 300 rpm (p<0.01). In conclusion the rotational speed of $ProTaper^{TM}$ files in the range of $250{\sim}400rpm$ does not affect the change of canal configuration, and high rotational speed reduces the instrumentation time. However appearance of separation and distortion of Ni-Ti rotary files can occur in high rotational speed.