• The Journal of the Korean dental association
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• v.47 no.11
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• pp.758-768
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• 2009

Purpose : Schulte introduced immediate implant cases in 1970s, since then many patients have been treated by immediate implants. The aim of this study was to evaluate the cumulative survival rate of immediate implant and to analyze various factors associated with survival of immediate implant in a 8-year period retrospectively. Materials and methods : From May, 2000 to October, 2007, 77 implants were placed in 63 patients immediately after tooth extraction at Department of Periodontology, Yonsei University Hospital. The implant survival rate was analyzed using a life-table analysis. After delivery of prosthesis, along 1 year of observation period, all implants were evaluated clinically and radiographically. Results : Among 77 implants, 59 were placed in maxilla and 18 in mandible. The most common site of the implantation was Mx anterior (65%). The overall survival rate was 94.8% over a mean follow-up period of $44.2{\pm}21$ months and the 8-year cumulative survival rate was 94.6%. Failure occurred in 4 implants, all of which were due to early failures. None of the following factors were significantly associated with the survival of immediate implants: advanced surgical technique including bone graft and guided bone regeneration, the types of implants, causes of tooth loss, and types of prosthesis. Conclusion : On the basis of 8-year life time analysis, immediate implant placement can be considered a safe and predictable treatment mordality.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.568-578
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• 2019

The nymphal development of the potato aphid, Macrosiphum euphorbiae (Thomas), was studied at seven constant temperatures (12.5, 15.0, 17.5, 20.0, 22.5, 25.0, and 27.5±1℃), 65±5% relative humidity (RH), and 16:8 h light/dark photoperiods. The developmental investigation of M. euphorbiae was separated into two steps, the 1^st through 2^nd and the 3^rd through 4^th stages. The mortality was under 10% at six temperatures. However, it was 53.0% at 27.5℃. The developmental time of the entire nymph stage was 15.5 days at 15.0℃, 6.7 days at 25.0℃, and 9.7 days at 27.5℃. In the immature stage, the lower threshold temperature of the larvae was 2.6℃ and the thermal constant was 144.5 DD. In our analysis of the temperature-development experiment, the Logan-6 model equation was most appropriate for the non-linear regression models (r²=0.99). When the distribution completion model of each development stage of M. euphorbiae larvae was applied to the 2-parameter and 3-parameter Weibull functions, each of the model's goodness of fit was very similar (r²=0.92 and 0.93, respectively). The adult longevity decreased as the temperature increased but the total fecundity of the females at each temperature was highest at 20℃. The life table parameters were calculated using the whole lifespan periods of M. euphorbiae at the above six temperatures. The net reproduction rate (R₀) was highest at 20.0℃(63.2). The intrinsic rate of increase (r_m) was highest at 25℃(1.393). The finite rate of doubling time (D_t) was the shortest at 25.0℃(2.091). The finite rate of increase (λ) was also the highest at 25.0℃(1.393). The mean generation time(T) was the shortest at 25.0℃(9.929).

• Korean journal of applied entomology
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• v.47 no.2
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• pp.163-168
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• 2008

Temperature dependent development of Tetranychus. urticae Koch was studied on the leaf of eggplant at 17, 22, 27, 32 and $37^{\circ}C$. T. urticae showed a minimum mortality at $27^{\circ}C$ and it increased at higher or lower temperatures than $27^{\circ}C$. The hatchability was low at 17 and $37^{\circ}C$. The duration of development decreased with increasing temperatures i.e., 5.3d at $37^{\circ}C$ and 25.8d at $17^{\circ}C$. Linear regression analysis of temperature vs. rate of development yielded the higher $r^2{\geq}0.88$ resulting in a good fit of the estimated line in the range of $17{\sim}37^{\circ}C$. Developmental zero temperature was $12.5^{\circ}C$ for the entire immature stage of female and $12.8^{\circ}C$ for that of male. Thermal constants were 80.5 and 74.7 degree days for those of female and male, respectively. Adult life span and oviposition period decreased with increasing temperatures. The number of eggs laid per female peaked at 141.0 eggs at $27^{\circ}C$, while that was a minimum 78.0 eggs at $37^{\circ}C$. Rate of hatchability, ratio of female, and $R_o$ were increased up to $27^{\circ}C$, and than declined thereafter. Intrinsic rate of natural increase (Rm) increased with rising temperatures and showed a maximum 0.5652 at $37^{\circ}C$. Also, ${\lambda}$ increased with increasing temperature. Doubling time (Dt) and generation time (T) decreased with increasing temperature.

• 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.

• Korean Journal of Breeding Science
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• v.42 no.2
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• pp.181-187
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• 2010

To understand the morphological differentiation of the 26 accessions of Foxtail Millet collected in Korea (15 accessions), China (7 accessions) and Pakistan (4 accessions), we analyzed 9 morphological characteristics such as plant height, panicle length, leaf number, tiller number, heading time, seed weight and panicle color etc. Most accessions of foxtail millet collected in Korea showed late heading time, tall plant height and long conical panicles. While foxtail millet accessions of Pakistan showed early heading time, short plant height and short conical panicles. In case of Chinese accessions, some accessions of them showed similar characteristics with Korean accessions, and the other showed similar characteristics to Pakistan accessions. In ANOVA analysis, most of quantitative characteristics such as plant height, leaf number, internode number and heading time showed significant differences among foxtail millet accessions collected from Korea, China and Pakistan. Principal component analyses clearly discriminate foxtail millet accessions of Korea from those of China and Pakistan. In PCA analysis, most of quantitative characters such as panicle length, leaf number and internode number greatly contributed in positive direction, whereas several quantitative characters such as tiller number, seed weight and panicle color contributed in negative direction on the first axis. Thus, these morphological characteristics could be used to classify the foxtail millet accessions collected in Korea, China and Pakistan. The present results could expand our understanding of the morphological variation in foxtail millet accessions from Korea, China and Pakistan, and also could be useful for foxtail millet germplasm preservation.

• Journal of KIISE:Information Networking
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• v.32 no.4
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• pp.443-451
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• 2005

Stateful inspection devices must maintain flow information. These devices create the flow information also for network attack packets, and it can fatally inflate the dynamic memory allocation on stateful inspection devices under network attacks. The memory inflation leads to memory overflow and subsequent performance degradation. In this paper, we present a guideline to set the flow entry timeout for a stateful inspection device to remove harmful embryonic entries created by network attacks. Considering Transmission Control Protocol (TCP) if utilized by most of these attacks as well as legitimate traffic, we propose a parsimonious memory management guideline based on the design of the TCP and the analysis of real-life Internet traces. In particular, we demonstrate that for all practical purposes one should not reserve memory for an embryonic TCP connection with more than (R+T) seconds of inactivity where R=0, 3, 9 and $1\leqq{T}\leqq{2}$ depending on the load level.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.524-530
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• 2002

A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Afferent signals from those receptors are transmitted to the vestibular nuclear complex, and the efferent signals from the vestibular nuclear complex control the eye movement and skeletal muscle contract. The postural disturbance caused by loss of the vestibular function results in nausea, vomiting, vertigo and loss of craving for life. The purpose of this study is to develop a off-vertical rotatory system for evaluating the function of semicircular canals and otolith organs, selectively, and visual stimulation system for- stimulation with horizontal, vortical and 3D patterns. The Off-vortical axis rotator is composed of a comportable chair, a DC servo-motor with reducer and a tilting table controlled by PMSM. And a double feedback loop system containing a velocity feedback loop and a position feedback loop is applied to the servo controlled rotatory chair system. Horizontal, vertical, and 3D patterns of the visual stimulation for applying head mounted display are developed. And wireless portable systems for optokinetic stimulation and recording system of the eye movement is also constructed. The gain, phase, and symmetry is obtained from analysis of the eye movement induced by vestibular and visual stimulation. Detailed data were described.

• Journal of Oriental Neuropsychiatry
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• v.25 no.3
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• pp.235-242
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• 2014

Objectives: The purpose of this research is to examine effects of acupuncture treatment on the autonomic nervous systems of Hwa-byung patients with insomnia. Methods: The study was performed through a patient-assessor blind, randomized, placebo-controlled trial in which the volunteers, data collectors, and analysts were unaware of which individuals were receiving the treatment. A total of thirty-seven volunteers were divided into 2 groups. Eighteen subjects were placed into a trial group and 19 subjects into a control group using a randomization table. The trial group was treated with bilateral Shigu, Ahnmyun, B62 (Shinmaek), and K6 (Chohae), while the control group was not given any other treatment. The ISI (Insomnia Severity Scale) was measured as the first evaluative instrument, and then a comparative analysis was conducted by comparing the results with those measured by ANS (BVP/HR, respiration rate, peripheral temperature, skin conductance, EMG). Results: In the BVP/HR, statistically significant decreases were found in those from the trial group compared to those of the control group. Skin conductance was found to be significantly increased in the trial group, as compared to the control group. However, there were no significant differences between the groups with respect to peripheral temperature, respiration rate, and EMG. Conclusions: The results suggest that acupuncture treatment is effective in the treatment of hwa-byung patients who suffer from insomnia due to their autonomic nervous systems.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.294-299
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• 2009

The studies were conducted constantly to detect emerging technology, in order to make sustainable growth of business and to make development of future nations. But there were many controversies because definition of emerging technology might be dependent of the subject's viewpoint and because it might be different to a point of time that emerging technology is applied to the present or the future. This paper sets times of emerging technology to the present and defines emerging technology as patents significantly used in developing current technology. US Patents and patent citation data were gathered from 1976 to 2007. We constructed hot patents pools that were utilized actively in developing new technologies regardless of times. We built a mapping table from IPC classification code to WIPO 32 technology category and analysed a half-life cycle according to specific technology groups.

• Journal of the Korean Home Economics Association
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• v.45 no.7
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• pp.1-15
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• 2007

The purpose of this study is getting information for making a plan of immigrant workers in Korea. As a first step to suggest plans for immigrant workers who have multi-cultural background, this study investigated to the domestic living of Koreans(ChoSun-Tribe) of Gillim province in China. For this, usage of domestic space questionnaire were used. Results of the research were as follows. 1. The most popular LDK type was the one which kitchen was separated from living room and dining room. Most of them thought that kitchen and living room have to be separated. 2. There was no plan for laundry room specially and most houses have a washing machine in the bathroom. Most houses didn't install a bathtub in the bathroom and they didn't think that it was indispensable. 3. It was estimated that they used a living room as a multi-purpose room for the family but used a master bedroom for its own purpose. 4. They used a table and chair for meals normally but they took meals sitting on the floor with a large family or guest. 5.All of them took off the shoes inside of the house for hygienic reason. There was no plan for the space to take on-off shoes in most houses and they just put the mat on the floor for it. 6. Modified Ondol system which use water pipe under the floor was popular in apartment while most detached houses had traditional Ondol system. The satisfaction about Ondol system was very high compared to other ones and also Ondol system was the most desirable one for ChoSun-Tribe.