• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.146-155
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• 1992

The natural mixed stand in Jindong-Ri, according to a recent study, showed the possibility of selection cutting as a silvicultural system based on the stand structure such as DBH distribution and height distribution. However, volume structure per DBH class of this stand had not a mature stand of selection cutting. In this study, wherefore, the rate of increment for DBH and volume was used to predict the future stand structure including volume distribution per DBH class. The possibility of selection cutting was then discussed using the future stand structure. From the prediction of future stand structure for 30 years per every 10 years, it could be concluded that the stand will be induced to selection cutting forest because of enough number of trees in objective DBH class and above, total volume per hectare, and the volume of large DBH class which can be harvested every year. However, this stand still did not show the structure of typical selection cutting which has the rate of 1 : 2 : 7 in the number of trees per hectare and the volume rate of 5 : 3 : 2 for large, medium, and small DBH class. This problem could be improved by appropriate silvicultural treatments.

• Journal of Chest Surgery
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• v.30 no.5
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• pp.512-516
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• 1997

We have experienced 66 cases of video assisted thoracic surgery(VATS) of spontaneous pneumothorax. The patients ranged in age from 1 Syears to 46years(mean age, 22.3years) and male patients were sixty three. The indications of video assisted thoracic surgery of spontaneous pneumothorax were recurrence, continuous air leakage, visible blabs on the chest X-ray & others. Infraoperative findings were as follows; blabs, pleural adhesion and pleural effusion. The operation was performed under general anesthesia wit double lumen endobronchial tube. Operative procedures included blebectomy and/or wedge resection of lung, vibramycin Pleurodesis with mechanical abrasion. In most cases, postoperative courses were uneventful and patients were discharged without significant complications. VATS provided the benefits of lesser postoperative pain, rapid recovery, short hospitalization, and smaller scar of wound. Conclusively VATS is a new interesting modality of surgical treatment of spontaneous pneumothorax and also can be extensively applicable in the diagnosis and treatment of other intrathoracic disease.

• Journal of Chest Surgery
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• v.31 no.11
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• pp.1076-1080
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• 1998

Background: Spontaneous hemopneumothorax, occurring in 1% to 12% of patients with spontaneous pneumothorax, is a rare disorder that can potentially lead to life-threatening complications. Materials and methods: We have experienced 15 cases (2.28%) with spontaneous hemopneumothorax among 659 episodes of spontaneous pneumothorax for eight years, from 1990 to 1997, at our hospital. We studied our previously treated patients by retrospective case studies to determine the nature of optimal management. Results: There were 14 male and 1 female patients whose mean age was 27.5 years, ranging from 19 to 58. The sides with disorder were as following: right in 10 cases and left in 5, unilaterally. The amount of initial bleeding ranged from 400 to 1,500 mL and 8 patients received a homologous blood transfusion. Patients exhibited symptoms of chest pain, dyspnea, chest discomfort, and hypovolemic shock. We concluded that causes of this disease in our patients were a torn pleural adhesion (14 cases) and a rupture of vascularized bullae (1 case with an underlying intrinsic lung disease, tuberculosis). All patients underwent closed thoracostomy and had good results except for 3. One patient underwent thoracotomy within 3 days from the onset because of continuous active hemorrhage. Decortication was required in one case because of a reactive fluid collection in the pleural space, which led to impaired lung expansion. Another patient underwent thoracotomy due to a ipsilateral recurrent pneumothorax without blood collection. Conclusions: The goals of treatment include hemostasis and reexpansion of the collapsed lung. Thus, if patients arrive early at hospital, closed thoracostomy and transfusion are thought to be sufficient treatments, although early surgical repair has been considered recently.

• Journal of agricultural medicine and community health
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• v.8 no.1
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• pp.19-27
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• 1983

This study was carried out to obtain the basic data for the prevention of chronic poisoning by organic phosphorous pesticides and to estimate the normal range of plasma cholinesterase activity level for Korean agricultural workers. The 285 agricultural workers were randomly selected for the study in Jungup Gun, Jeonbug Province, 135 persons of them were tested in the period of pre-exposure of organophosphorous pesticides (April 1981) and rest of them were tested after exposure(August 1981). Cholinesterase activity levels were measured by the Micro-method of Takahashi Hiroshi. Major findings are as following: 1) There is significant difference in plasma cholinesterase activity levels between the pro-exposed and post exposed group(p > 0.01). Mean values of plasma cholinesterase activity levels were $7.60{\pm}1.74{\mu}M/20{\mu}{\ell}$/hr. in the pre-exposed group and $6.23{\pm}1.59{\mu}M/20{\mu}{\ell}$/hr. in the post-exposed group. 2) Plasma cholinesterase activity in Korean agricultural worker could be estimated $7.30-7.90{\mu}M/20{\mu}{\ell}$/hr. with 95% confidence interval.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.26-26
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• 2018

본 연구는 DMZ 및 접경지역에서 생육하고 있는 자생식물에 대하여 조사된 연구자료와 국립수목원 DMZ자생식물원에서 자체 조사로 수행된 미조사지역 연구 등을 집대성한 DMZ 일원의 관속식물상 가운데 행정구역상 고성군, 인제군, 양구군, 화천군에 해당하는 동부지역 관속식물의 유용자원 현황에 대하여 기초자료를 제공하고자 하였다. 동부지역은 고성군의 석호들을 포함한 저층습지 및 해안지역과 설악산(1,708m), 점봉산(1,424m), 화악산(1,468m), 등의 고산지대, 대암산(1,304m) 정상부근에 위치한 고층습지 용늪(1,280m)까지 이르는 다양한 생활환경 특성을 포함하고 있다. DMZ일원의 관속식물상 157과 754속 2,047종 12아종 340변종 105품종 총 2,504분류군 중 40.2%인 111과 438속 873종 4아종 113변종 17품종 1,007분류군이 확인된 동부지역 유용식물의 조사 결과 식용식물 순채, 고려엉겅퀴, 병풍쌈 등 336분류군(33.3%), 사료용식물 산뽕나무, 고광나무, 새 등 334분류군(33.1%), 약용식물 주목, 백부자, 삼지구엽초 등 270분류군(26.8%), 관상용식물 제비동자꽃, 백작약, 만병초 등 118분류군(11.7%), 목재용식물 일본잎갈나무, 소나무, 오동나무 등 38분류군(3.7%), 염료용식물 밤나무, 매발톱나무, 갈매나무 등 26분류군(2.5%) 섬유용 식물 개모시풀, 쐐기풀, 참싸리 등 8분류군(0.7%), 산업용식물 굴참나무, 붉나무, 노박덩굴 3분류군(0.2%), 용도를 알지 못하는 식물 280분류군(27.8%)으로 나타났다.

• Korean Journal of Environment and Ecology
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• v.31 no.1
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• pp.1-23
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• 2017

Gwangchiryeong, located adjacent to the Korean DMZ, is a mountain pass connecting Yang-Gu, Gangwon-do with In-je. It reaches a height of 800m (2,624ft) and stands on the flank of Mt. Daeam-san, which has an elevation of 1,304m (4,278ft). It is important to survey the flora of Gwangchiryeong in that not only the area encompassing the waterfall and the valley along with dense old-growth forest has various plant species but also it is a way to make out what kind of plant species exist in the DMZ due to the geographical characteristics of Gwangchiryeong adjacent to the Korean DMZ. Therefore, this study was conducted to elucidate the distribution of vascular plants and their value in Gwangchiryeong. The vascular plants that were collected 9 times from April 2014 to September 2015, and consisted of a total of 513 taxa: 88 families, 297 genera, 441 species, 4 subspecies, 62 varieties and 6 forms. Among those observed species, the rare plant species designated by Korea Forest Service were 22 taxa including Hanabusaya asiatica, Paeonia japonica, Saxifraga octopetala, etc. Endemic species were 22 taxa containing Cirsium setidens, Heloniopsis koreana, Salvia chanryoenica, etc. 18 taxa were recorded as naturalized plants and their naturalized rate and urban index were noted as 3.5% and 5.6%. Among the surveyed 513 taxa, edible, medicinal, pasturing, ornamental, timber, dye, fiber and industrial plants were 197 taxa, 154 taxa, 180 taxa, 49 taxa, 24 taxa, 8 taxa, 4 taxa and 3 taxa, respectively.

• Journal of Korea Water Resources Association
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• v.52 no.5
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• pp.313-323
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• 2019

Deep Tunnel system is a large-scale urban flood control facility installed underground in order to reinforce the lack of drainage systems in developed cities. In a structure like a deep tunnel system, the undular bore generated in the downstream causes a problem in the hydraulic stability of the tunnel. In this study, to investigate the influence of the undular bore on the hydraulic stability at the "Shinwol rainwater storage and drainage system", under construction for the first time in the country, a hydraulic model experiment was conducted on various flooding inflow scenarios. As a result of the hydraulic model experiment carried out in this study, the undular bore generated downstream is trapped in the pipe while moving to upstream, pushes the compressed air. It is judged that overflow occurred by choking the vertical drop shaft in the process when this compressed air is being exhaust through the upstream vertical drop shaft and blocking flood inflow. In addition, the analysis of velocity of undular bore shows that the undular bore transfers energy, and at this time, the pressure rose in the pipe and the velocity increment occurred of the undular bore. Further studies are needed to predict the size and velocity of undular bore, which plays an important role in the hydraulic stability of the tunnel in the deep tunnel system.

• Journal of the Korean Society of Radiology
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• v.16 no.2
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• pp.131-139
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• 2022

The purpose of this study was to insert a pedicle screw into a pig thoracic vertebrae, a general CT scan(Non MAR), and a thoracic axial image obtained with the Metallic Artifact Reduction for Orthopedic Implants (O-MAR) to reduce artifacts. The image obtained by reconstructing the algorithm (Standard, Soft, Bone, Detail) was used using the image J program. Signal to noise ratio(SNR) and contrast to noise ratio(CNR) were compared and analyzed by obtaining measured values based on the given equation. And this study was to investigate tube voltage and algorithm suitable for CT scan for thoracic pedicle screw insertion. As a result, when non-MAR was used, the soft algorithm showed the highest SNR and CNR at 80, 100, 120, and 140 kVp, On the other hand, when MAR was used, the standard algorithm showed the highest at 80 kVp, and the standard and soft algorithms showed similar values at 100 kVp. At 120 kVp, the Soft and Standard algorithms showed similar values, and at 140 kVp, the Soft algorithm showed the highest SNR and CNR. Therefore, when comparing Non-MAR and MAR, even if MAR was used, SNR and CNR did not increase in all algorithms according to the change in tube voltage. In conclusion, it is judged that it is advantageous to use the Soft algorithm at 80, 100, 120, and 140 kVp in Non MAR, the Standard algorithm at 80 and 100 kVp in MAR, and the Soft algorithm at 120 and 140 kVp. This study is expected to serve as an opportunity to further improve the quality of images by using selective tube voltage and algorithms as basic data to help evaluate images of pedicle screw CT scans in the future.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.281-288
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• 2022

In this study, four algorithms (Soft, Standard, Detail, Bone) were used for general CT scan (Before MAR) images and MAR (After MAR) images for patients with metal implants inserted into the hip joint. was applied to compare and analyze Noise, SNR, and CNR to find out the optimal algorithm for quantitative evaluation. As the analysis method, Image J program, which can calculate image analysis and area and pixel values on the image reconstructed with four algorithms, was used. In order to obtain Noise, SNR, and CNR, the HU mean value and HU SD value were obtained by designating the bone (ischium) closest to the metal implant in the image for the measurement site, and the background noise was the surrounding muscle. The region of interest (ROI) was equally designated as 15 × 15 mm in consideration of the size of the bone, and the values of SNR and CNR were calculated according to the given equation. As a result, for noise, After MAR and Soft algorithms showed the lowest noise, and SNR and CNR showed the highest for Before MAR and Soft algorithms. Therefore, the soft algorithm is judged to be the most appropriate algorithm for metal implant hip joint CT.

• Journal of Korean Foot and Ankle Society
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• v.25 no.4
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• pp.149-156
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• 2021

Purpose: Given the lack of definite evidence-based guidelines in clinical practice, there may be a wide variation in treatment protocols for osteochondral lesions of the talus (OLT). Based on the Korean Foot and Ankle Society (KFAS) member survey, this study aimed to report the current trends in the management of OLT. Materials and Methods: A web-based questionnaire containing 30 questions was sent to all KFAS members in September 2021. The questions were mainly related to clinical experience and preferences in diagnosis, conservative, and surgical treatments for patients with OLT. Answers with a prevalence of ≥50% of respondents were considered a tendency. Results: Sixty-two (11.3%) of the 550 surgeons queried responded to the survey. The responses to 9 (30.0%) of the total of 30 questions established a tendency. Answers exhibiting a tendency were as follows; additional diagnostic tools except for plain radiograph (magnetic resonance imaging), most common conservative treatment method (oral medication, rest), most important radiological factor in decision making for surgical treatment and method (size of the lesion, ankle instability, loose bodies), most important patient factors in decision making for surgical treatment and method (age, activity or occupation), infrequently requiring posterior arthroscopy (less than 3%), most common revision surgery for failed bone marrow stimulation procedure (osteochondral autograft transplantation [OAT]), not requiring additional procedure for donor site in OAT, the main reason for unsatisfactory result after OAT (persistent pain without radiological abnormality), no generalization of autologous chondrocyte implantation or chondrogenesis using stem cells. Conclusion: This study presents updated information on current trends in the management of OLT in Korea. Both consensus and variations in the approach to patients with OLT were revealed through this survey. Since recent biologic efforts to regenerate cartilage have been unsuccessful, further studies to identify clinical evidence would be needed.