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The Study on the Debris Slope Landform in the Southern Taebaek Mountains (태백산맥 남부산지의 암설사면지형)

  • Jeon, Young-Gweon
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.77-98
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    • 1993
  • The intent of this study is to analyze the characteristics of distribution, patter, and deposits of the exposed debris slope landform by aerial photography interpretation, measure-ment on the topographical maps and field surveys in the southern part Taebaek mountains. It also aims to research the arrangement types of mountain slope and the landform development of debris slopes in this area. In conclusion, main observations can be summed up as follows. 1. The distribution characteristics 1)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of intrusive rocks with the talus line. 2)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of inrtusive rocks with the talus line. 2) From the viewpoint of distribution altitude, talus is mainly distributed in the 301~500 meters part above the sea level, while the block stream is distributed in the 101~300 meters part. 3) From the viewpoint of slope oriention, the distribution density of talus on the slope facing the south(S, SE, SW) is a little higher than that of talus on the slope facing the north(N, NE, NW). 2. The Pattern Characteristics 1) The tongue-shaped type among the four types is the most in number. 2) The average length of talus slope is 99 meters, especially that of talus composed of hornfels or granodiorite is longer. Foth the former is easy to make free face; the latter is easdy to produce round stones. The average length of block stream slope is 145 meters, the longest of all is one km(granodiorite). 3) The gradient of talus slope is 20~45${^\circ}$, most of them 26-30${^\croc}$; but talus composed of intrusive rocks is gentle. 4) The slope pattern of talus shows concave slope, which means readjustment of constituent debris. Some of the block stream slope patterns show concave slope at the upper slope and the lower slope, but convex slope at the middle slope; others have uneven slope. 3. The deposit characteristics 1) The average length of constituent debris is 48~172 centimeters in diameter, the sorting of debris is not bad without matrix. That of block stream is longer than that of talus; this difference of debris average diameter is funda-mentally caused by joint space of bedrocks. 2) The shape of constituent debris in talus is mainly angular, but that of the debris composed of intrusive rocks is sub-angular. The shape of constituent debris in block stream is mainly sub-roundl. 3) IN case dof talus, debris diameter is generally increasing with downward slope, but some of them are disordered and the debris diameter of the sides are larger than that of the middle part on a landform surface. In block stream, debris diameter variation is perpendicularly disordered, and the debris diameter of the middle part is generally larger than that of the sides on a landform surface. 4)The long axis orientation of debris is a not bad at the lower part of the slope in talus (only 2 of 6 talus). In block stream(2 of 3), one is good in sorting; another is not bad. The researcher thinks that the latter was caused by the collapse of constituent debris. 5) Most debris were weathered and some are secondly weathered in situ, but talus composed of fresh debris is developing. 4. The landform development of debris slopes and the arrangement types of the mountain slope 1) The formation and development period of talus is divided into two periods. The first period is formation period of talus9the last glacial period), the second period is adjustment period(postglacial age). And that of block stream is divided into three periods: the first period is production period of blocks(tertiary, interglacial period), the second formation period of block stream(the last glacial period), and the third adjustment period of block stream(postglacialage). 2) The arrangement types of mountain slope are divided into six types in this research area, which are as follows. Type I; high level convex slope-free face-talus-block stream-alluvial surface Type II: high level convex slope-free face-talus-alluvial surface Type III: free face-talus-block stream-all-uvial surface Type IV: free face-talus-alluval surface Type V: talus-alluval surface Type VI: block stream-alluvial surface Particularly, type IV id\s basic type of all; others are modified ones.

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Clinical Analysis of the Surgical Treatments for Large Primary Spontaneous Pneumothorax (외과적 치료를 시행한 대량 일차성 자연기흉의 임상분석)

  • Kim, Byung-Ho;Huh, Dong-Myung;Han, Won-Kyung
    • Journal of Chest Surgery
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    • v.42 no.3
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    • pp.344-349
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    • 2009
  • Background: The clinical history and physical findings of the patients with spontaneous pneumothorax depend largely on the extent of the collapse of the lung and the presence of pre-existing pulmonary disease. Large primary spontaneous pneumothorax is a possible serious condition and. so more active treatment will be necessary for these patients. The therapeutic guideline for large pneumothorax remains controversial. Therefore, by assessing the clinical results of surgical treatment for large primary pneumothorax, we aim to determine the indicators of treatment. Material and Method: Among 348 patients with primary spontaneous pneumothorax and who underwent surgical treatment from August 2004 through December 2007, 58 patients who responded to treatment for a large primary pneumothorax were included in the current study. We then retrospectively evaluated the operative findings and the surgical results. The patients with a pneumothorax of 80% or more, including those patients with tension pneumothorax, were considered to have a "large pneumothorax". Most of these patients Should be treated with a 12F chest tube. Thoracoscopic wedge resection was considered for treating recurrent pneumothorax, continuous air leakage, controlateral pneumothorax and first episode pneumothorax with visible blebs (> 1cm) seen on the computed tomography. Result: There were 50 men and 8 women with a mean age of 28.2 years (range: $14\sim54$ years). The mean length of hospitalization was 5.3 days (range: $2\sim10$ days). Nine patients underwent chest tube drainage only. Forty-nine patients underwent thoracoscopic wedge resection. The mean follow up time was 27.8 months (range: $10\sim58$ months). The actual site of air leakage could be located in 35 patients (71.4%) and this was correlated with pleural adhesion (p=0.005). The initial air leakage tended to be more correlated with intra-operative air leakage, although this was not statistically significant (p=0.066). The recurrence rate was 11.1 % for the patients with chest tube drainage and 2.0% for the patients with thoracoscopic wedge resection. Conclusion: Large primary pneumothorax requires an early diagnosis and early treatment. Thoracoscopic wedge resection may help to prevent recurrence of large primary pneumothorax.

EMG AND CEPHALOMETRIC STUDY ON CHANCES IN UPPER AIRWAY STRUCTURES AND MUSCLE ACTIVITIES ACCORDING TO THE USE OF MANDIBULAR REPOSITIONING APPLIANCE AND BODY POSTURE IN OSA PATIENTS (폐쇄성 수면 무호흡증 환자에 있어서 하악 재위치 장치 장착과 체위에 따른 상기도 구조와 근활성도의 변화에 관한 EMG 및 두부방사선학적 연구)

  • Park, Young-Chel;Pae, Eung-Kwon;Lee, Jeung-Gweon;Lee, Jong-Suk;Kim, Tae-Kwan
    • The korean journal of orthodontics
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    • v.28 no.4 s.69
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    • pp.547-561
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    • 1998
  • Obstructive sleep apnea (OSA) is a disorder characterized by repetitive episode of upper airway collapse during sleep. Recent studies showed that not only the anatomic factors but the physiologic factors of the upper airway also have effcts on the occurrence of apnea and that the genioglossus muscle also plays an important role in the maintenance of the upper airway. A variety of therapies were performed to treat OSA, and among them the use of mandibular repositioning appliances showed reasonable results. But there is still a lack of research on the structural and physiological mechanism upon the use of mandibular repositioning appliances. The author selected 26(male 17, female 9) OSA patients that came to the Yonsei University Dental Hospital, Department of Orthodontics, and 20 normal adults (male 10, female 10) and took cephalometric radiographs of them in a supine position before and after the placement of the mandibular repositioning appliance to see the structural changes of the upper airway and compare the therapeutic effects between the two groups. We also studied the waking genioglossus muscle activity in OSA patients and investigated the difference in the electromyogram of the genioglosssus muscle upon the change in body posture and the use of mandibular repositioning appliance. Following results were obtained. 1. Among the cephalometric measurements of the upper airway structure, the length of the soft palate, maximum thickness of the soft Palate and SPAS, MAS, VAL, H-H1, MP-H showed statistically significant differences between the normal and OSA groups, but the IAS and EAS showed no statistically significant differences between the two groups. 2. In both the normal and OSA groups, as the epiglottis moved forward on wearing the mandibular repositioning appliance, the epiglottis level of the upper airway increased and the maximum thickness of the soft palate changed and the hyoid bone also moved forward, but the IAS in both groups showed various results and the effect of the mandibular repositioning appliance on the structure of the upper airway was different in the two groups. 3. Upon changing the position, the electromyogram of the genioglossus muscle showed a increasing tendency but there was no statistically significant differences, and when the mandibular repositioning appliance were worn there was a statistically significant increase in the electromyogram of the genioglossus muscle in both the upright and supine positions. The mandibular repositioning appliances not only have an effect on the anatomical structure of the upper airway but also on the physiology of the upper airway. There are different responses to the use of mandibular repositioning appliance between the normal and OSA groups therefore it could be considered to have the different physiology of the upper airway between the two groups.

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The Reconstruction with Extracorporeal Irradiated Autograft for Osteosarcoma of Extremities (사지 골육종에서 체외 방사선 조사를 이용한 재건술)

  • Kim, Jae-Do;Lee, Gun-Woo;Chung, So-Hak
    • The Journal of the Korean bone and joint tumor society
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    • v.16 no.1
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    • pp.1-7
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    • 2010
  • Purpose: With advances in various treatment modalities, limb salvage surgery has been commonly used in osteosarcoma of extremities. An alternative method for skeletal reconstruction is reimplantation of the tumor bearing bone following extracorporeal irradiation (ECI). We report the long-term results of ECI autograft in aspect of the oncological and functional outcomes, and complications. Materials and Methods: We retrospectively reviewed 31 osteosarcoma patients who underwent reconstruction with ECI between July 1995 and January 2006. There were 24 males and 7 females with a mean age of 24 (7-74 years) and a mean follow-up of 117 months (17-177 months). Twenty-five cases were reconstructed with ECI autograft, 6 cases with ECI autograft-prosthesis composite. The pathologic subtypes were conventional in 29 cases, periosteal in 1 case, and parosteal in 1 case. The most common location of tumor was distal femur (15 cases) followed by humerus (3), proximal fibula (3) and proximal tibia (3). Musculoskeletal Tumor Society (MSTS) score was used for functional evaluation. The overall survival rate, local recurrence, complications were analyzed. Results: The overall survival rate was 80.6% and the disease-free survival rate was 64.5%. Five patients died of distant metastasis. One patient required above-knee amputation due to local recurrence. All of them, twenty-three complications occurred, which included nonunion in 7 cases, deep infection in 5 cases, joint instability in 4 cases, metal failure in 2 cases, Limb-length discrepancy (LLD) in 2 cases, periprosthetic fracture in 1 case, epiphyseal collapse in 1, local recurrence in 1 case. The mean MSTS functional score was 62.5%. Conclusion: Extracorporeal irradiated autograft can be achieved relatively good result in aspect of oncological and functional aspect, but is needed to be additional research about occurring many complications. The reconstruction with ECI after intercalary or fragmentary resection is effective reconstruction in aspect of oncological and functional result, complications.

Geomorphic Features of Bing-gye Valley Area(Kyongbuk Province, South Korea) -Mainly about Talus- (의성 빙계계곡 일대의 지형적 특성 -테일러스를 중심으로-)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
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    • v.4 no.2
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    • pp.49-64
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    • 1998
  • Bing-gye valley(Kyongbuk Province, South Korea) is well known as a tourist attraction because of its meteorologic characteristics that show subzero temperature during midsummer. Also, there are some interesting geomorphic features in the valley area. Therefore, the valley is worth researching in geomorphology field. The aim of this paper is to achieve two purposes. These are to clarify geomorphic features on talus within Bing-gye valley area, and to infer the origin of Bing-gye valley. The main results are summarized as follows. 1) The formation of Bing-gye valley It would be possible to infer the following two ideas regarding the formation of Bing-gye valley. One is that the valley was formed by differential erosion of stream along fault line, and the other is that the rate of upheaval comparatively exceeded the rate of stream erosion. Especially, the latter may be associated with the fact that the width of the valley is much narrow. Judging that the fact the width of the valley is much narrow, compared with one of its upper or lower valley, it is inferred that Bing-gye valley is transverse valley. 2) The geomorphic features of talus (1) Pattern It seems to be true that the removal of matrix(finer materials) by the running water beneath the surface can result in partly collapse hollows. Taluses are tongue-shaped or cone-shaped in appearance. They are $120{\sim}200m$ in length, $30{\sim}40m$ in maximum width. and $32{\sim}33^{\circ}$ in mean slope gradient. The component blocks are mostly homogeneous in size and shape(angular), which reflect highly jointed free face produced by frost action under periglacial environment. (2) Origin On the basis of previous studies, the type of the talus is classified into rock fall talus. When considered in conjunction with the degrees of both weathering of blocks and hardness of blocks, it can be explained that the talus was formed under periglacial environment in pleistocene time. (3) The inner structure of block accumulation I recognize a three-layered structure in the talus as follows: (a) superficial layer; debris with openwork texture at the surface, 1.3m thick. (b) intermediate layer: small debris(about 5cm in diameter) with fine matrix(including humic soil), 70cm thick. (c) basal layer: over 2m beneath surface, almost pure soil horizon without debris (4) The stage of landform development Most of the blocks are now covered with lichen, and/or a mantle of weathering. It is believed that downslope movement by talus creep well explains the formation of concave slope of the talus. There is no evidence of present motion in the deposit. Judging from above-mentioned facts, the talus of this study area appears to be inactive and fossil landform.

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