• Title/Summary/Keyword: 김용하

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Temporary replacement of congenital missing incisors on mandible using temporary anchorage devices in growing patient: 2-year follow-up (성장기 아동에서 교정용 골성 고정원을 이용한 선천 결손 하악 전치의 임시 보철 수복: 2년 경과 관찰)

  • Choi, Youn-kyung;Kwon, Eun-Young;Jung, Kyung-Hwa;Choi, Na-Rae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.4
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    • pp.272-281
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    • 2020
  • Agenesis of permanent tooth in adolescent patients can be treated either by orthodontic treatment for space closure or by maintaining the space until implant restoration can be carried out in adult. However, gradual atrophy of alveolar bone width makes it difficult to restore the prosthesis in the future or may cause unaesthetic results. Therefore, maintaining of not only the missing space but also the alveolar bone width should be considered. This case is a treatment whereby a temporary replacement of missing 2 mandibular incisors in adolescent patient was carried out using 2 temporary anchorage devices (TADs). Two TADs were placed horizontally 2 - 3 mm below the top of alveolar ridge, and fixed with artificial teeth by stainless steel wires extended. During the 2 year follow-up, neither gingival inflammation nor loss of the TADs have occurred. In the radiographic evaluation, the growth of the adjacent alveolar bone was not inhibited, and the width of the alveolar bone was maintained.

A Study of Pervasive Roaming Services with Security Management Framework (퍼베이시브 로밍 서비스를 위한 보안 관리 프레임워크)

  • Kim, Gwan-Yeon;Hwang, Zi-On;Kim, Yong;Uhm, Yoon-Sik;Park, Se-Hyun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.17 no.4
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    • pp.115-129
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    • 2007
  • The ubiquitous and autonomic computing environments is open and dynamic providing the universal wireless access through seamless integration of software and system architectures. The ubiquitous computing have to offer the user-centric pervasive services according to the wireless access. Therefore the roaming services with the predefined security associations among all of the mobile devices in various networks is especially complex and difficult. Furthermore, there has been little study of security coordination for realistic autonomic system capable of authenticating users with different kinds of user interfaces, efficient context modeling with user profiles on Smart Cards, and providing pervasive access service by setting roaming agreements with a variety of wireless network operators. This paper proposes a Roaming Coordinator-based security management framework that supports the capability of interoperator roaming with the pervasive security services among the push service based network domains. Compared to traditional mobile systems in which a Universal Subscriber Identity Module(USIM) is dedicated to one service domain only, our proposed system with Roaming Coordinator is more open, secure, and easy to update for security services throughout the different network domains such as public wireless local area networks(PWLANs), 3G cellular networks and wireless metropolitan area networks(WMANs).

Study on Estimation of Unmanned Enforcement Equipment Installation Criteria and Proper Installation Number (무인교통단속장비 설치 판단 기준 및 설치대수 산정 연구)

  • So, Hyung-Jun;Kim, Yong-Man;Kim, Nam-Seon;Hwang, Jae-Seong;Lee, Choul-Ki
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.6
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    • pp.49-60
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    • 2020
  • The number of traffic control equipment installed to prevent traffic accidents increases every year due to continuous installation by the National Police Agency and local governments. However, it is installed based on qualitative judgment rather than engineering analysis results. The purpose of this study was to present additional installations in the future by presenting the installation criteria considering the severity of accidents for each road type and calculating the appropriate number of installations. ARI indicators that can indicate the severity of traffic accidents were developed, and road types were classified through analysis of variance and cluster analysis, and accident information by road type was analyzed to derive ARI of clusters with high traffic accident severity. The ARI values required to determine the installation of equipment for each road type were presented, and 5,244 additional installation points were analyzed.

Orthodontic intrusion treatment of mandibular anterior teeth in a periodontal patient with hyperdivergent skeletal pattern: 8-year follow-up (장안모를 보이는 치주 질환자에서 하악 전치의 압하를 통한 과개 교합 치료: 8년 경과 관찰)

  • Kwon, Eun-Young;Jung, Kyung-Hwa;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il;Choi, Youn-kyung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.37 no.1
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    • pp.48-60
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    • 2021
  • Patients who have extruded anterior teeth and deep bite with pathologic tooth migration, it is necessary not only periodontal treatment for reduce inflammation, but also orthodontic treatment for intrusion of anterior teeth. However, it is difficult to place the orthodontic brackets due to the deep bite, and there is a problem that the extrusion of the posterior teeth occurs more easily than the intrusion of the anterior teeth biomechanically. In particular, in patients with long face, relative intrusion of the anterior teeth by extrusion of the posterior teeth causes the clockwise rotation of the mandible and makes the facial profile worse. Therefore the biomechanical consideration and appliance design that can block these problems are required from the treatment plan. This is a patient who had a deep overbite with extruded anterior teeth, treated by periodontal treatment and intrusion of mandibular anterior teeth using cute brackes and miniscrews, and resulted in favorable maintenance during 8-year retention.

A Study on Transferring Cloud Dataset for Smoke Extraction Based on Deep Learning (딥러닝 기반 연기추출을 위한 구름 데이터셋의 전이학습에 대한 연구)

  • Kim, Jiyong;Kwak, Taehong;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.38 no.5_2
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    • pp.695-706
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    • 2022
  • Medium and high-resolution optical satellites have proven their effectiveness in detecting wildfire areas. However, smoke plumes generated by wildfire scatter visible light incidents on the surface, thereby interrupting accurate monitoring of the area where wildfire occurs. Therefore, a technology to extract smoke in advance is required. Deep learning technology is expected to improve the accuracy of smoke extraction, but the lack of training datasets limits the application. However, for clouds, which have a similar property of scattering visible light, a large amount of training datasets has been accumulated. The purpose of this study is to develop a smoke extraction technique using deep learning, and the limits due to the lack of datasets were overcome by using a cloud dataset on transfer learning. To check the effectiveness of transfer learning, a small-scale smoke extraction training set was made, and the smoke extraction performance was compared before and after applying transfer learning using a public cloud dataset. As a result, not only the performance in the visible light wavelength band was enhanced but also in the near infrared (NIR) and short-wave infrared (SWIR). Through the results of this study, it is expected that the lack of datasets, which is a critical limit for using deep learning on smoke extraction, can be solved, and therefore, through the advancement of smoke extraction technology, it will be possible to present an advantage in monitoring wildfires.

Ultrasound-Guided Greater Occipital Nerve Block for Primary Headache: Comparison of Two Techniques by Anatomical Injection Site (일차성 두통에서 초음파 유도 하 후두신경 차단술: 해부학적 주사부위에 따른 두 가지 테크닉의 비교)

  • Yoo, Myung Chul;Kim, Hee-Sang;Lee, Jong Ha;Yoo, Seung Don;Yun, Dong Hwan;Kim, Dong Hwan;Lee, Seung Ah;Soh, Yunsoo;Kim, Yong;Han, Young Rok;Kwon, Jung Ho;Jang, Haneul;Chon, Jinmann
    • Clinical Pain
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    • v.18 no.1
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    • pp.24-30
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    • 2019
  • Objective: Greater occipital nerve block (GONB) is a widely accepted treatment of primary headaches. Two ultrasound (US)-guided blockade techniques exist: 1) the classical distal nerve block technique performed medial to the occipital artery at the superior nuchal line, and 2) the new proximal nerve block technique performed at the obliquus capitis inferior muscle at the level of C2. Our study aim was to perform a head-to-head comparative study of these two US-guided techniques. Method: Forty-nine patients with primary headache treated in our university hospital were recruited. Patients were randomized into two groups of the classical nerve block and the new proximal nerve block techniques. The headache questionnaire was made to assess the intensity of the pain of headache attacks, number of days they experience headache, duration of headache, and amount of pain medication they consumed. Results: In both groups, a decrease in the severity and frequency of the headache was observed. There was no measurable difference in outcome between the two groups. Conclusion: Our study showed that the classic and new proximal techniques are equally effective in decreasing the headache severity and frequency.

The assessment of dentoalveolar compensation in facial asymmetry individuals: integration of cone beam CT and laser scanned dental cast images (Cone beam CT 영상과 석고모형 레이저 스캔 영상의 결합을 이용한 안면비대칭자의 치성보상 평가)

  • Song, Hyo-Kyung;Son, Woo-Sung;Park, Soo-Byung;Kim, Seong-Sik;Kim, Yong-Il
    • The korean journal of orthodontics
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    • v.40 no.6
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    • pp.373-382
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    • 2010
  • Objective: The purpose of this study was to assess the dentoalveolar compensation in facial asymmetry individuals using an integration of a CBCT image and a laser scanned dental cast image. Methods: The subjects consisted of 30 adults with asymmetric mandibles and 20 adults with symmetric mandibles. The CBCT and laser scanned dental cast images were integrated with a registration technique. Canine and first molar position and angulation were assessed from reference coordinates. The differences between deviated and non-deviated sides were analyzed with the paired t-test. The differences shown according to menton deviation were also statistically analyzed using Pearson correlation analysis. Results: The experimental group showed deviated and non-deviated side differences (dev.-ndev.) in the position and angle of the canine and first molars. Menton deviation showed positive correlation with the deviation side (dev.-ndev.) for the maxillary and mandibular 1st molar angles, negative correlation with the deviation side for the vertical position of the maxillary 1st molars, transverse position of the mandibular canine, transverse position and vertical position of the mesio-lingual cusp of the mandibular 1st molars. Conclusions: The upper and lower canine and first molars of facial asymmetry individuals were compensated, so the transverse position, vertical position, and angle showed differences between the deviated/non-deviated sides.

Effects of Methyl Ethyl Ketone and Methanol on the Survival and Reproduction of Paronychiurus kimi (Collembola: Onychiuridae) (메틸에틸케톤과 메탄올이 김어리톡토기의 사망 및 번식에 미치는 영향)

  • Wee, June;Lee, Yun-Sik;Son, Jino;Kim, Yongeun;Mo, Hyoung-ho;Cho, Kijong
    • Korean Journal of Environmental Biology
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    • v.35 no.2
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    • pp.169-174
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    • 2017
  • Acute and chronic toxicities of methyl ethyl ketone and methanol were investigated on Paronychiurus kimi (Collembola), for evaluating the potential effects of accidental exposures of these chemical substances on the terrestrial environments. This study was undertaken to establish a toxicity database for these chemical substances, which was required for the preparation of the response compensation and liability act for agricultural production and environmental damage. The 7-d acute toxicity and 28-d chronic toxicity were conducted using the OECD artificial soil spiked with varying, serially diluted concentrations of methyl ethyl ketone and methanol. Mortality was recorded after 7-d and 28-d of exposures, and the number of juveniles were determined after 28-d of exposure in the chronic toxicity test. In both assessments, methanol was more toxic than methyl ethyl ketone in terms of mortality ($LC_{50}$) and reproduction ($EC_{50}$). The 7-d $LC_{50}$ of methyl ethyl ketone and methanol were 762 and $2378mg\;kg^{-1}$ soil dry wt., respectively, and the 28-d $LC_{50}s$ were 6063 and $1857mg\;kg^{-1}$ soil dry wt., respectively. The 28-d $EC_{50}$ of methyl ethyl ketone and methanol were 265 and $602mg\;kg^{-1}$ soil dry wt., respectively. Comparison of results obtained in this study with literature data revealed that P. kimi was more sensitive to methanol than other soil invertebrates. However, given the high volatility of the chemicals tested in this study, further studies are necessary to improve the current test guideline, or to develop new test guidelines for an accurate assessment of chemicals that require toxicity databases for chemical accidents.

Study of Prediction Model Improvement for Apple Soluble Solids Content Using a Ground-based Hyperspectral Scanner (지상용 초분광 스캐너를 활용한 사과의 당도예측 모델의 성능향상을 위한 연구)

  • Song, Ahram;Jeon, Woohyun;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.33 no.5_1
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    • pp.559-570
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    • 2017
  • A partial least squares regression (PLSR) model was developed to map the internal soluble solids content (SSC) of apples using a ground-based hyperspectral scanner that could simultaneously acquire outdoor data and capture images of large quantities of apples. We evaluated the applicability of various preprocessing techniques to construct an optimal prediction model and calculated the optimal band through a variable importance in projection (VIP)score. From the 515 bands of hyperspectral images extracted at wavelengths of 360-1019 nm, 70 reflectance spectra of apples were extracted, and the SSC ($^{\circ}Brix$) was measured using a digital photometer. The optimal prediction model wasselected considering the root-mean-square error of cross-validation (RMSECV), root-mean-square error of prediction (RMSEP) and coefficient of determination of prediction $r_p^2$. As a result, multiplicative scatter correction (MSC)-based preprocessing methods were better than others. For example, when a combination of MSC and standard normal variate (SNV) was used, RMSECV and RMSEP were the lowest at 0.8551 and 0.8561 and $r_c^2$ and $r_p^2$ were the highest at 0.8533 and 0.6546; wavelength ranges of 360-380, 546-690, 760, 915, 931-939, 942, 953, 971, 978, 981, 988, and 992-1019 nm were most influential for SSC determination. The PLSR model with the spectral value of the corresponding region confirmed that the RMSEP decreased to 0.6841 and $r_p^2$ increased to 0.7795 as compared to the values of the entire wavelength band. In this study, we confirmed the feasibility of using a hyperspectral scanner image obtained from outdoors for the SSC measurement of apples. These results indicate that the application of field data and sensors could possibly expand in the future.

Effect of Seed-gathering Time and After-ripening on Seed Emergence of Paeonia lactiflora Pall (작약종자(芍藥種子)의 채종시기(採種時期)와 후숙(後熟)이 출아(出芽)에 미치는 영향(影響))

  • Chung, Sang-Hwan;Suh, Dong-Hwan;Kim, Ki-Jae;Lee, Kwang-Seok;Choi, Boo-Sul;Kim, Yong-Han
    • Korean Journal of Medicinal Crop Science
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    • v.1 no.1
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    • pp.10-15
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    • 1993
  • This study was carried out to identify the effect of seed gathering time and after-ripening on Paeonia lactiflora Pall (PL) seed emergence, and to establish optimal seed gathering time and sowing time. We used two local cultivar of PL ; Punggi and Uisung. Seeds were gathered 6 times from 5th July to 25th August in 1992. The seeds of Punggi local cultivar were planted by the planting density of $10\;{\times}\;15cm$ after treatment of 7 ways ; without after-ripening, with after-ripening for 10, 20, 30 days without or with capsule. We investigated the change of 100 grains weight of PL seed by the passage of time and emergence rate after treatment. The seed weight of Punggi was heavier than that of Uisung and the seed weight was maximzed at 25th July both of the two, and then decreased by the passage of time. The seed emergence rate of Punggi gathered at 5th July was showed 7.8% and the seed emergence of Uisung was later 10 days than that of Punggi. The maximum emergence rate of two local cultivars was the highest in gathering the seeds on the 15th of August. In gathering the seeds without and with capsule, the emergence rate of seeds sowed with after-ripening was higher than that of seeds sowed immediately after gathering the seeds without after-ripening when the seeds gathered between 5th July and 5th August. In after-ripening with out and with capsule, the emergence rate of 10 days after-ripening seeds was less than that of 20 and 30 days after-ripening seeds after the seeds gathered on the 5th and 15th of July. Difference of the emergence rate of seeds by after-ripening time did not show when the seeds gathered after 25th July.

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