• Title/Summary/Keyword: 견인성

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A Study about the Change of Locations of the Center of Resistance According to the Decrease of Alveolar Bone Heights and Root Lengths during Anterior Teeth Retraction using the Laser Reflection Technique (Laser 반사측정법을 이용한 전치부 후방 견인시 치조골 높이와 치근길이 감소에 따른 저항중심의 위치변화에 관한 연구)

  • Min, Young-Gyu;Hwang, Chung-Ju
    • The korean journal of orthodontics
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    • v.29 no.2 s.73
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    • pp.165-181
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    • 1999
  • Treatment mechanics should be individualized to be suitable for each patient's personal teeth and anatomic environment to get a best treatment result with the least harmful effects to teeth and surrounding tissues. Especially, the change of biomechanical reaction associated with that of the centers of resistance of teeth should be considered when crown-to-root ratio changed due to problematic root resorption and/or periodontal disease during adult orthodontic treatment. At the present study, in order to investigate patterns of initial displacements of anterior teeth under certain orthodontic force when crown-to-root ratio changed in not only normal periodontal condition but also abnormal periodontal and/or teeth condition, the changes of the centers of resistance for maxillary and mandibular 6 anterior teeth as a segment were studied using the laser reflection technique, the lever & pulley force applicator and the photodetector with these quantified variables reducing alveolar bone 2mm by 2mm for each of maxillary 6 anterior teeth until the total amount of 8mm and root 2mm by 2mm for each of mandibular 6 anterior ones until the total amount of 6mm. The results were as follows: 1. Under unreduced condition, the center of resistance during initial displacement of maxillary 6 anterior teeth was located at the point of about $42.4\%$ apically from cemento-enamel junction(CEJ) of the averaged tooth of them and kept shifting to about $76.7\%$ with alveolar bone reduction. 2. The distance from the averaged alveolar crest level of maxillary 6 anterior teeth to the center of resistance for the averaged tooth of them kept decreasing with alveolar bone reduction, but the ratio to length of the averaged root embedded in the alveolar bone was stable at around $33\%$ regardless of that. 3. Under unreduced condition, the center of resistance during initial displacement of mandibular 6 anterior teeth was located at the Point of about $43\%$ apically from CEJ of the averaged tooth of them and this ratio kept increasing to about $54\%$ with root reduction. But the distance from CEJ to the center of resistance decreased from around 5.3mm to around 3.3mm, that is to say, the center of resistance kept shifting toward CEJ with the shortening of root length. 4. A unit reduction of alveolar bone had greater effects on the change of the centers of resistance than that of root did during initial Phase of each reduction. But both of them had similar effects at the middle region of whole length of the averaged root.

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A Study on Measures to Create Local Webtoon Ecosystem (지역웹툰 생태계 조성을 위한 방안 연구)

  • Choi, Sung-chun;Yoon, Ki-heon
    • Cartoon and Animation Studies
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    • s.51
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    • pp.181-201
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    • 2018
  • The cartoon industry in Korea has continued to decline due to the contraction of published comics market and decrease in the number of comic books rental stores until the 2000s when it rapidly started to experience qualitative changes and quantitative growth due to the emergence of webtoon. The market size of webtoon industry, valued at 420 billion won in 2015, is expected to grow to 880.5 billion won by 2018. Notably, most cartoonists who draw cartoon strips are using digital devices and producing scripts in data, thereby overcoming the geographical, spatial and physical limitation of contents. As a result, a favorable environment for the creation of local ecosystems is generated. While the infrastructures of human resources are steadily growing by region, cartoon industries that are supported by the government policy have shown good performance combined with factors of creative infrastructures in local areas such as webtoon experience centers, webtoon campuses and webtoon creation centers, etc. Nevertheless, it is true that cartoon infrastructures are substantially based on a capital area which leads to an imbalanced structure of cartoon industry. To see the statistics, companies of offline cartoon business in Seoul and Gyeonggi Province make up 87%, except for distribution industry. In addition, companies of online cartoon business which are situated outside of Seoul and Gyeonggi Province form merely 7.5%. Studies and research on local webtoon are inadequate. The existing studies on local webtoon usually focus on its industrial and economic values, mentioning the word "local" only sometimes. Therefore, this study looked into the current status of local webtoon of the present time for the current state of local cartoon ecosystem, middle and long-term support from the government, and an alternative in the future. Main challenges include the expansion of opportunities to enjoy cartoon cultures, the independence of cartoon infrastructure, and the settlement of regionally specialized cartoon cultures. It means that, in order to enable the cartoon ecosystem to settle down in local areas, it is vital to utilize and link basic infrastructures. Furthermore, it is necessary to consider independence and autonomy beyond the limited support by the government. Finally, webtoon should be designated as a culture, which can be a new direction of the development of local webtoon. Furthermore, desirable models should be continuously researched and studied, which are suitable for each region and connect them with regional tourism, culture and art industry. It will allow the webtoon industry to soft land in the industry. Local webtoon, which is a growth engine of regions and main contents of the fourth industrial revolution, is expected to be a momentum for the decentralization of power and reindustrialization of regions.

Surgical Clues of Distal Anterior Cerebral Artery(DACA) Aneurysms (원위부 전대뇌 동맥류 수술의 실마리)

  • Kim, Sung Bum;Yi, Hyeong Joong;Kim, Jae Min;Bak, Koang Hum;Kim, Choong Hyun;Oh, Suck Jun
    • Journal of Korean Neurosurgical Society
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    • v.29 no.12
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    • pp.1555-1562
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    • 2000
  • Objects : Surgical management of the distal anterior cerebral artery(DACA) aneurysms presents several unique problems to surgeons, such as difficulty in early identification of parent arteries, high incidence of rebleeding and premature rupture, and requirement of unfamiliar approach other than conventional frontotemporal craniotomy. Therefore, preoperative anatomical knowledge of anterior interhemispheric fissure and entry point of dissection is prerequisite. Authors utilized a frontobasal approach for DACA aneurysms by using consistent external landmark for guidance to the deep structure. Materials and Methods : From Nov. 1995 to Jun. 1999, a surgical clipping of DACA aneurysms was carried out in 9 patients among a total 131 patients with intracranial aneurysms. In each case, the clinical and aneurysmal features were carefully reviewed through the angiograms, medical records, and intraoperative findings. Results : The incidence of DACA aneurysms was 6.9% from our series. All cases were arisen from juxtacallosal por-tion ; 6 cases from pericallosal-callosomarginal(PC-CM) junction and 3 from pericallosal-frontopolar(PC-FP) junction. Associated vascular anomalies were noted in 3 cases and multiple aneurysms in 3 cases, respectively. The preoperative clinical grades were generally poor. An early surgery was performed in 7 cases and frontobasal interhemispheric approaches in 7 cases. Postoperatively, two patients died of complications ; one delayed ischemic vasospasm and one aspiration pneumonia but remaining patients recovered well. Conclusion : The frontobasal interhemispheric approach was useful for DACA aneurysms in early surgery. Division of superior sagittal sinus(SSS) enabled a minimal retraction of brain on both sides, and prevention of intraoperative rupture was possible. Authors suggest the frontopolar(first frontal bridging) vein as a constant external landmark for approaching the genu of the corpus callosum and juxtacallosal DACA aneurysms.

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Phylogenetic Relationships of Jeju Dogs to Other Domestic and Foreign Dog Breeds Determined by Using mtDNA D-loop Sequences (mtDNA D-loop의 염기서열에 의한 제주견과 우리나라 재래견 및 외국견품종과의 유연관계)

  • Kim, Mi-Gyoung;Kim, Nam-Young;Lee, Sung-Soo;Kim, Ky-IL;Yang, Young-Hoon
    • Journal of Animal Science and Technology
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    • v.53 no.4
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    • pp.303-310
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    • 2011
  • Phylogenetic relationships of Jeju dogs to other domestic and foreign dog breeds were assessed using mtDNA D-loop sequences. Neighbor-joining trees were constructed using complete sequences (970 bp excluding the tandem repeat region) determined for five Cheju, four Jindo, four Sapsaree, five Pungsan, two of each East and West Laika dogs (Canis familiaris), two gray wolves (Canis lupus) and two coyotes (Canis latrans) and also published complete sequences for dogs. Coyote sequences were used as outgroups. In addition, a total of 214 haplotypes of 598bp D-loop sequences from 30 dog breeds were collected from GenBank and used to investigate genetic structure of population. In the analyses of full D-loop sequence variation and the phylogenetic trees constructed by neighbor-joining method, neither haplotypes nor clades specific for any domestic dog breeds were observed. The inter-species sequence variation (4.51%) between domestic dogs and wolves was much higher than the intra-species sequence variation within domestic dogs (1.63%) and wolves (3.64%). The divergence of the dog and wolf occurred approximately 1~2 million years ago based on these values. The taxa of Jeju dog breed in the phylogenetic tree are clustered separately and intermingled with other taxa of breeds, suggesting that active crossbreeding of Jeju dogs with other domestic breeds.

The Influence of Healthcare Service Nature on Job Performance : The Moderating Effects of Individaul Personality (의료서비스의 서비스본질 특성이 직무성과에 미치는 영향 :개인성향을 조절변수로)

  • Byun, Miyoung;Kim, Hyunsoo
    • Journal of Service Research and Studies
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    • v.9 no.4
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    • pp.41-62
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    • 2019
  • In this intangible good-oriented, modern service economy era, we have to first understand the characteristics of the healthcare service in order to enhance the competitiveness of the healthcare industry and achieve continuous growth. In addition, service nature and characteristics should be reinforced so that connections can be made to the organizational job performance. To achieve the aforementioned results, this study analyzes the direct effects service nature and characteristics have on job performance in the healthcare industry and investigates the indirect effects with individual personality as the moderating effect. While conducting this study, a total of 340 healthcare workers were surveyed. Survey data from a total of 315 workers were used for analysis during empirical investigation of the research hypothesis. According to the analysis, it was proven that interactivity and horizontality among service nature and characteristics have a positive (+) effect on job effectiveness. This means that customer needs can be identified at customer touchpoints to quickly and accurately provide customers with the products and services they want, while horizontality among service nature and characteristics have a positive (+) effect on job effectiveness. This means that customer needs can be identified at customer touchpoints to quickly and accurately provide customers with the products and services they want, while horizontal communication enhance from department to department and from colleague to colleague within the organization can be linked to job performance. Also, with regards to the relationship shared between the customer or the patient, the job performance of healthcare workers may also improve if they provide customers with their desired service as an expert at the same level. In a rapidly changing healthcare environment, if the healthcare service nature and characteristics are put into practical use, it will be possible to propel the growth of hospitals and sustain it while investigating the moderating effects of individual personality, a partial moderating effect was observed for self-esteem and growth desire. As the study on service nature and characteristics came about only just recently, there is a needs for futher research. The study focuses on the healthcare service industry and hopefully, it will serve as a base study that can be applied to different service industries as well.

Size and Retention of Tongue Bulb for Tongue Retaining Device (혀 유지구의 크기와 유지력 평가)

  • Park, Nam-Seon;Lee, Ki-Ho;Kim, Mee-Eun;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
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    • v.32 no.3
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    • pp.283-292
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    • 2007
  • In several treatment modalities for snoring and obstructive sleep apnea (OSA), oral appliances mainly including mandibular advancement appliance (MAA) and tongue retaining device (TRD) are recognized as a non-invasive, reversible alternative with favorable results. Tongue bulb is a major component of TRD which prevents the tongue from approaching the posterior wall of the pharynx and can be combined with MAA. Determination of tongue bulb size for the patient is important for therapeutic effect, but frequently needs time-consuming work. For effective fabrication and standardization of tongue bulbs, this study aimed to categorize tongue bulb size for healthy young men and to examine its relation with maximum retention force and with physical parameters including tongue-related variables. 36 non-snoring, asymptomatic young men with normal occlusion were voluntarily participated in this study (mean age: $24.47{\pm}2.58$ years). Experimental procedures consisted of prefabrication of tongue bulb set (20 types with a width of 27-36mm and thickness of 8 and 10 mm), determination of tongue bulb size and the maximum retention force for each subject, and measurement of physical parameters including body mass index (BMI), neck circumference and width, thickness and length of tongue. This study showed that there was significant difference of retention force among the bulb size-related groups both in upright and supine position (p<0.05) and that retention force increased with bulb size. Correlation of tongue bulb size with physical parameters was not clearly verified and there was no significant difference in retention force between upright and supine positions. Based on our results, it can be suggested that retention force relates with tongue bulb size, ultimately with tongue volume. A further study needs to be performed in the patients with snoring and OSA.

Clinical Study on Laryngo - Microscopic Surgery For Vocal Nodules and Polyps (후두결절 및 폴립의 후두미세 수술에 관한 임상연구)

  • 문영일
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1983.05a
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    • pp.11.2-11
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    • 1983
  • Vocal nodules and polyps are much more frequent in singers, public speakers, teachers and actors. Voice trauma and voice misuse, at times associated with mild inflammatory reaction, appear to be important in their etiology. It is generally agreed that vocal cord nodules and polyps are inflammatory in nature and they arise in the subepithelial layer of loose connective tissue of the vocal cord. Since the junction of anterior and middle thirds of the membranous cord and has the greatest amplitude of vibration. This is the site of predilection for vocal cord nodules. The author performed laryngomicrosurgery for 70 cases of vocal nodules and polyps at Ewha Womans University Hospital during the period of 5 years. The result obtained were as follows ; 1) Surgical excision is not necessarily the best approach because vocal nodules in the early stages will resolve with the simplest voice therapy. 2) In children, surgery is rarely indicated because most nodules in children regress during adolescence. 3) For patients who use their voices professionally, voice therapy is indicated for three months. 4) If after three month of conservative treatment the cord lesion does not improve and the patient it still dissatisfied with his voice, laryngomicrosurgery can then be considered. 5) The small cuffed endotracheal tube in the interarytenoid space helps to keep the cords immobile and in an abducted position. 6) Removal of the nodule shoule be started by gentle retraction posteriorly and as soon as a tear appears anterior to the nodule. 7) On occasion it is preferable to start the dissection with a siccle knife while the nodule is held on the stretch. 8) Voice rest should be maintained for a week following which the free edges of the cords are usually healed.

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Measuring Economic Values of Amenity Services from Urban Greenspaces in the Seoul Metropolitan Area Using Choice Experiments (선택실험을 이용한 서울 도시녹지 어메니티의 경제가치 평가)

  • Choi, Andy S.;Eom, Young Sook
    • Environmental and Resource Economics Review
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    • v.27 no.1
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    • pp.105-138
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    • 2018
  • This paper reports novel empirical results of a choice experiment that elicited the economic values that residents in the Seoul metropolitan area place on the amenity services realized from the landscape views and accessibilities to urban green spaces (i.e., mountains, rivers and urban parks). The 1,000 respondents in the sample were divided into two residential of housing types (apartments vs. houses) and occupancy types (owners vs. tenants). Residents living in apartments are willing to pay an average of 28% (5.0 million KRW per year) above the current housing prices per household for a mountain view, compared to an apartment view from their living room. Their willingness to pay values are about 22% (4.0 million KRW per year) and 10% (1.8 million KRW per year) respectively for a river view and a urban park view. Economic benefits of having access (i.e., a 10 minutes working distance) to mountains, rivers and urban parks are estimated to be an average of 16% (2.9 million KRW per year), 20% (3.6 million KRW per year) and 18% (3.2 million KRW per year), respectively, above the current housing prices per household. On the other hand, access benefits for those residing in houses are 18% (4.7 million KRW per year), 16% (4.1 million KRW per year) and 22% (5.6 million KRW per year) per household, respectively. They are also willing to pay an average of 35% (8.9 million KRW per year) above the current housing prices for keeping or having a garden or vegetation bed. Furthermore, a strong "greenspace premium" is centered around the three Gangnam districts for house-dwellers, whereas it is areas of "new real estate boom" for apartment dwellers.

Hybrid Natural Orifice Transluminal Endoscopic Cholecystectomy in Dogs: Transgastric, Transcolonic and Transvaginal Approaches (개에서 자연개구부를 통한 하이브리드 내시경적 담낭절제술: 경위장관, 경결장 및 경질 접근법)

  • Kim, Soo-Hyun;Jeong, Seong-Mok;Shin, Sa-Kyeng;Kim, Seong-Su;Shin, Beom-Jun;Lee, Jae-Yeon;Park, Ji-Yeong;Kim, Myung-Cheol;Kim, Young-Il;Lee, Sang-Il;Kim, Ji-Yeon
    • Journal of Veterinary Clinics
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    • v.28 no.5
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    • pp.497-505
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    • 2011
  • Natural orifice transluminal endoscopic surgery is a newly emerging technique recently, with its many potential advantages in clinical practice. Cholecystectomy by Hybrid NOTES in this work, performed with single working channel endoscope in conjunction with a laparoscopic grasping forceps in dogs, is a "bridge" between laparoscopic procedure and pure NOTES. Three different approaches for cholecystectomy were carried out; transgastric, transcolonic and transvaginal. In all three approaches, abdominal opening was made by a 5 mm trocar, followed by making pneumoperitoneum of 4 mmHg with $CO_2$ insufflator. Transgastric cholecystectomy, single working channel endoscope was advanced to the peritoneal cavity through gastric incision in antral region made by endoscopic needle knife. Endoscope was retroflexed to visualize the gall bladder. Transcolonic access, incision for endoscopic entry was done at right ventral wall of descending colon, 15 cm inside from the anus. Incision in transvaginal access was made at right-ventral region, just caudal to the caudal tubercle. With the simple traction by the laparoscopic grasping forceps, good visualization of surgical field was obtained in all three groups. Cystic duct and artery were ligated with endoclips; for complete gall bladder dissection from liver, L-knife was used. Closure of incision sites were done in transgastric and transcolonic cholecystectomy by endoclips, not in transvaginal approach.

A Comparative Analysis of Masan's Democratic Movement : The 3·15 Uprising in 1960 and the 10·18 Buma Uprising in 1979. (마산의 민주화운동 비교 분석: 1960년 3·15의거와 1979년 10·18부마항쟁)

  • Chung, Joo-Shin
    • Korea and Global Affairs
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    • v.3 no.2
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    • pp.5-58
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    • 2019
  • The purpose of this article is to bring about 10.26 accident by providing a fuse for the overthrow of the Park Chung-hee administration in the 10.18 Buma uprising. So, first of all, this article has a main purpose in analyzing the comparison between Masan's 3.15 uprising and 10.18 Buma uprising. The purpose of the study is to compare the 3.15 democratic movement in Masan with the 10.18 Buma uprising, given that the incident laid the foundation for the dictator to be overthrown in the event of an anti-dictatorial movement in Masan. The research method of this article is intended to be used as a research method in the 3.15 and 10.18 protests, given that if a person in power conducts election fraud or suppresses anti-government movements in order to maintain the system, it could lead to the destruction of those in power. In the end, the Masan 3.15 uprising and 10.18 uprising failed to reach a direct attempt to overthrow the regime due to unfinished democratic movements, but with the revolution of 4.19 and the massive political transformation of 10.26 Accident, he achieved the leading role theory that allowed the Rhee Syngman and Park Chung-hee administrations. In eradicating authoritarian regimes, however, the historic significance of the democratization movement was that the authoritarian regime eventually brought about the collapse of the regime by making a hard-line stance on election schemes or popular protests over the trap of power boomerang, which causes the regime to collapse.