• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.132-132
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• 2000

환경오염과 이상기후의 영향으로 인한 수자원의 고갈과 함께 국내의 경우 수자원 개발 계획 및 수요량을 감안할 때 향후 7 년 내에 물부족 현상을 겪을 것이라는 보고가 있 었으며, 환경부담을 줄이기 위해 폐수의 배출기준은 강화되고 있다. 이러한 상황에서 제조 특성상 타 업종에 비해 폐수 발생량이 높은 편인 국내의 제지산업은 여러 해전부터 이에 대 한 방안을 모색하여 왔다. 일반적으로 폐수 수질 관리와 청수 사용량의 절감을 위해 고가의 폐수 처리 장치를 설치하거나 폐수 재활용을 통해 공정을 극도로 폐쇄화하는 방안으로 연구 가 진행되어 왔다. 이 중 용수의 재활용이 가장 경제적인 방법이지만, 재활용이 지속될수록 각종 무기염과 콜로이드성 유기물질이 축적되어 각종 약품의 효능 저하, 탈수속도의 저하 및 생산 제품의 품질 악화 등의 문제를 유발한다고 알려져 있다. 이를 해결하고자 하는 노 력으로 펄프 원료에 따른 공정수 내 용해성 물질의 분석과 재활용 횟수에 따른 각종 SS와 D DS의 축적 정도에 대한 기초 연구가 수행되었으며, 고폐쇄화된 공정에서 성능을 발휘할 수 있는 첨가제의 개발과 적용 방법에 대한 연구도 수행된 바 있다.여러 지종 가운데 골판지 원지는 용수의 재활용률이 상당히 높은 지종이기 때문에 공정수의 재활용이 진행될수록 열악한 저급 원료로부터 각종의 다양한 물질이 용출 혹은 배 출되며, 이러한‘물질은 골판지 원지의 강도 발현에 더욱 악영향을 미칠 것으로 판단되었다. 미세분으로 구성된 SS의 경우 이미 많은 연구를 통해 특성이 파악되었기 때문에 본 연구에 서는 ss를 제외한 공정수를 두 가지로 크게 나누어 고려하였다. 즉, ss로 측정되지 않지만 닥도를 유발할 수 있는 미세 무기물질과, 용해성의 무기염, 첨가제 및 추출물 둥으로 이루어 진 용해성 성분으로 나누어 분석하였으며, 또한 각각이 초지 특성에 미치는 영향을 살펴보 고자 하였다.을 해석코자 하였으며, 그 방법으 로 수치해석기법을 도입하였다. 또 실제 캘린더링 전후의 두께 변화를 측정하여 유리전이온도 의 도달 깊이와 비교하였다. 지필의 압축 정도는 롤의 직경과 닙 폭을 이용하여 MD 방향으 로 함수화하였으며, 열전달 계수로는 겉보기 값을 사용하였다. 이때 지펼은 균질한 것으로 가 정하였다. 함수율은 유리전이온도를 좌우하는 가장 큰 인자이나 본 연구에서는 항온항습처리 를 통해 유입지의 함수율을 고정시켰으며 캘린더링 시 함수율의 변이는 없다고 가정하였다. 그 결과 열침투깊이가 증가할수록 지필은 보다 변형되기 쉬운 상태가 되어 주어진 압력 조건에 대해 소성변형 정도가 증가하는 것으로 나타났다. 이는 캘린더링 전후에 두께 변화를 측정하여 정량적으로 평가할 수 있었다. 수치해석기법을 통해 같은 압력 조건에서 온도가 증 가함에 따라 혹은 같은 온도 조건에서 압력이 증가함에 따라 지필 내의 유리전이온도의 침투 깊이가 증가함을 알 수 있었으며 이는 캘린더링 전후의 두께 변화의 측정 결과와 일치하였 다. 또 NRT가 증가함에 따라서도 유리전이온도 침투 깊이가 증가하였다.합편에 비해 일부 우수한 양상을 보였지만 본 실험의 범위내에서는 통계적 정량적 차이를 제시할 수는 없었다. 향후 보다 광범위한 동물 실험이 필요할 것으로 사료된다.된다.하고도 완전교정술 도달 확률이 높은 치료전략이라는 사실을 입증하였으며 주대동맥폐동맥혈관부행지의 크기나 숫자가 단일화하기 쉬운 형태학적 특징을 지닌 경우에는 조기에 일단계완전교정술을 시행하여 양호한 결과를 얻을 수 있다는 사실을 발견하였다. 반면 본 환아군 중 단일화술을 먼저 시도한 군에서는 비록 단계적인 단일화를 시도한 군에서 단일화술과 관계된 수술사망율이 약간 낮기는 하였으나 완전교정술까지 완료될 가능성에는 차이가 없었다. 그러나 이 경우 보다 정련된 적응 환자의 선택을 통한 단일화 우선전략의 시도와 장기 추

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.2
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• pp.157-161
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• 2001

The purpose of this study cephalometrically evaluated changes in the posterior airway space for patients with obstructive sleep apnea syndrome(OSAS) before and after surgical advancement of the maxilla and mandible. The change in calculated airway resistance was correlated with the respiratory disturbance index(RDI). Twenty cephalometric radiographs were traced before and after surgery to determine the posterior airway area and calculate resistance. Polysomnograms of each patient were obtained before and after surgery. All patients had a decrease in calculated airflow resistance in the airway. The mean amount of resistance was 865.15 before surgery, decreasing to 192.65 after surgery (p<0.01). Eighty-five percent of the patients experienced improvement in their RDI. Reduction in the RDI appears to be due to an increase in the posterior airway space and decrease in flow resistance.

• Journal of Mushroom
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• v.3 no.3
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• pp.115-118
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• 2005

This study was carried out to investigate the cultural charateristics of Fomitopsis pinicola in log woods. The optimal conditions for log cultivation as follows; 1) Light effect, natural light 2) $CO_2$, 0.2% below 3) Low temperature shock, $15^{\circ}C$ for 5 days 4) log-length, 100~120cm 5) It takes 52~65 days for primodia induction is possible to harvest fruiting bodies for 5~6 months. Meanwhile, the total of 10 species pest including Trichoderma sp. occurred during the cultivation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.2
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• pp.145-151
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• 1994

앞 턱 부위가 짧고 후방으로 위치해 있을 때 턱의 높이를 증가시키고 전방으로 돌출시키는 축조 이부성형술의 방법으로는, 매식체 삽입술, 골 절단술, 골 절제술 또는 이들을 동시에 시행하는 혼합술등이 행해져 왔다. 그러나 매식체 삽입술에서는 감염 또는 매식체의 유동성 등의 합병증의 발병이 빈발하고 매식체의 밑 부위에 골이 흡수된다든지 연조직의 변화를 예측하기 어렵다든지 하는 복잡한 문제점들이 종종 보고되고 있다. 따라서 매식체를 이용하지 않는 골 절단술이나 골 절제술만을 이용한 다양한 방법의 이부성형술이 많이 시행되고 있다. 하악골이 전후방 관계로 발육부전인 환자에게 양측 하악지 시상분할술을 시행하여 전방 이동시킨 후 앞 턱의 위치를 좀더 개선하기 위하여 $Michel{\'{e}}t$ 테크닉의 변형법을 이용한 이부성형술을 추가로 시행하였다. 이 방법의 이부성형술은 턱의 수직적, 수평적 길이를 증가시키기 위하여 하악결합면 부위에 장부와 장붓구멍 모양을 한 골 절단술을 시행하고 광범위한 연조직경을 보존하여 골편으로의 혈류 차단을 최소화하였으며 나사를 이용한 견고한 고정을 용이하게 하였다. 이 술식은 턱을 수직적으로 증가시킬 때 두 골편 사이의 공간에 골 이식을 시행할 필요가 없으며, 금속판을 이용하지 않아도 정확한 위치에 골편을 고정하기가 용이하고, 또한 고정용 나사가 향후 골형성 부위에 위치하게 된다는 장점을 경험하게 되어 이에 한 증례를 보고하는 바이다.

• Journal of Chest Surgery
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• v.34 no.7
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• pp.534-538
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• 2001

Background: Knowledge of size and morphology of the normal trachea is important for airway management and tracheal reconstruction. Conventional radiography is a simple method used to measure the tracheal diameter, but it is not accurate because of the artifacts related to image magnification and overlapping by the shoulder. The purpose of this study was to provide the normal values of the tracheal size and anatomy in Korean adults using Computerized Topography. Material and Method: There were 43 men and 34 women included in this study. They were divided into three age groups(group 1, 20-39 years ; group 2, 40-59 yeas , groups 3, $\geq$60 years). The anteroposterior and transverse diameters and cross - sectional areas of the trachea were measured at the level of the thoracic inlet(Level 1) and the aortic arch(Level 2). These values obtained at each level were compared between age groups and sexes. Result: In 43 men, the anteroposterior / transverse diameters(mean SD in millimeters) of the trachea at levels 1 and 2 were 19.95$\pm$2.99 / 17.72$\pm$2.13 and 19.77$\pm$2.57 / 18.02$\pm$2.19, respectively. In 34 women, those values at levels 1 and 2 were 15.56$\pm$2.12 / 14.18$\pm$2.07 and 15.35$\pm$1.82 / 15.00$\pm$1.60, respectively. At both levels, the anteroposterior and transverse diameters were significantly greater in men than in women (p<0.05). The cross-sectional area of the trachea at levels 1 and 2 were 279.14$\pm$61.37 / 281.93$\pm$63.97 $\textrm{mm}^2$ in men and 173.29$\pm$35.81 / 181.88$\pm$34.74 in women, respectively. They also showed significantly greater values in men than in women(P<0.05). There was no significant difference in diameters and cross-sectional areas of the trachea between age groups. Conclusion: There are significant differences in the internal diameter and cross- sectional area of the trachea between men and women in normal Korean adults, while the age difference was insignificant. We believed CT is a relatively accurate and safe way to measure the internal diameter and cross-sectional areas of the trachea.

• Current Research on Agriculture and Life Sciences
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• v.31 no.2
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• pp.131-138
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• 2013

The precision aerial application of small farms, such as paddy, upland and orchard fields using agricultural unmanned helicopters became a new paradigm. The objective of this study was to evaluate the performance of a GPS module and algorithm, controlling drift of agricultural helicopter by the crosswind and maintaining the position for emergency landing. Purpose of the drift control, of which an algorithm works while hovering is related with the emergency sequence that coping with abnormal conditions of rotorcraft system. However, the inertial attitude control cannot detect a drifting motion of fuselage moving at the constant velocity, thus the crosswind takes the helicopter away from the landing position. Performance of the drift control module, based on the GPS that a hovering position did not deviate within 5m in diameter, were tested and evaluated. Initially, the reaction against a disturbing gust wind was sensitive, soon the helicopter maintained its locking position and azimuth within 5m in diameter. It was, however, difficult for the helicopter to recognize the swaying and nodding, the some deviation was expected due to the discrepancy characteristics of the GPS signal. The performance of the drift control proved the effectiveness of the module to maintain the position against an unintended drift during the emergency landing or hovering.

• Journal of Yeungnam Medical Science
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• v.5 no.2
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• pp.87-93
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• 1988

The diagnosis of OPCA could be made clinically with important aid of brain CT scanning, although the definite and conclusive diagnosis only by postmortem pathological determination. We reviewed, clinically and with brain CT examination, 12 cases of patients with OPCA who were admitted to the Yeungnam University Hospital for a recent 5 years. The result were as following. : 1. The distribution of age is from 49 to 72, mainly 50 to 60. Man is more frequent than women at the 4.5 times. 2. The interval period from Sx. onset to diagnosis is 1 year to 6 years. 3. The usual initial Sxs. were dizziness(58%), ataxia(33%), and other less frequent Sxs. were weakness of low extremities, dysarthria, headache and urinary incontinence. The clinical manifestations at the initial diagnosis were cerebellar disturbance(100%), dysarthria(83%), and increased deep tendon reflexes(58%). 4. The results of brain CT finding are like this : ${\cdot}$ the width of cerebellar sulci is more than 1mm, other 4 cases more than 2mm. ${\cdot}$ the width of cerebellar pontine cistern of the patient if usually 3 to 4mm, other 2 cases extended to the 5mm. ${\cdot}$ the A. P and lateral lengths of 4th. ventricle is 4mm and 4 to 8mm respectively. ${\cdot}$ 6 cases of whole patients show coincidentally cerebral atrophy.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.100-106
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• 2018

This study was fulfilled to investigate the anatomical characteristics according to provinces. In order to compare anatomical characteristics between provinces we selected Goseong, Hongcheon, and Bonghwa as experimental sites. To use the tree rings formed at the same years we dated all tree rings by cross-dating method used in dendrochronology and the cutting years were successfully dated in 2014, 2012, and 2014 for woods from Goseong, Hongchen, and Bonghwa, respectively. Based on the cutting years tracheid lengths and widths were measured considering juvenile wood (tree rings between the pith and first 10 years), heartwood (tree rings formed between 1955 and 1964), and sapwood (tree rings formed between 2002 and 2011). According to the results about differences between tracheid lengths from three provinces, juvenile wood did not show a difference, statistically, but heartwood and sapwood showed differences as the tracheid lengths following Bonghwa, Hongcheon, and Goseong. Bongwha also showed the largest value in the trachied width among three provinces. The tracheid lengths in the radial direction increased up to around the first 20 years, and then they showed stabilized. All wood samples showed typical Korean red pine's characteristics in anatomical observation under a light microscope.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.931-937
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• 2018

Sutures are used not only for wound closure but also for oriental medicine field, beauty and even for plastic surgery. Especially, it is popular in the field of cosmetic surgery. In this paper, we produced sutures using PCL and PLLA with better strength than PDO sutures, which was widely used in the past. To learn about the mechanical characteristics of the PCL and PLLA sutures, the contraction change, tensile strength, and elongation were measured. And SEM was also analyzed for diameter and surface. The contraction change Ratio of sutures are stabilized after a certain period of time regardless of temperature. Also, it can be seen that the higher the temperature, the higher the contraction increase rate. And the rate change of mechanical properties is different according to the temperature before and after the glass temperature. Also the higher the temperature, the faster the molecular motion and the lower the tensile strength. The diameter of the PLLA and PCL sutures is opposite to the contraction change ratio. And it is considered that the sterilization temperature of PLLA sutures is best to set at $45^{\circ}C$ and the sterilization temperature of PCL sutures is best to set at $35^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.613-621
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• 2014

This study was conducted to estimate the changes of stand diversity before and after applying three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. Data were collected in the natural deciduous forests in Pyungchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and the each of silvicultural treatments was applied to three sampling plots, respectively. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after the silvicultural treatments. In this study, two different indices related to each of stand diversity indices such as contagion, DBH-difference, height-difference, and mingling were estimated and compared to analyze the differences of stand diversity among the stands before and after silvicultural treatments. As a result, total eight stand diversity indices were used to analyze the differences among structures of stands managed by three different silvicultural treatments. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand diversity among the stands. The results revealed that stand structures seem to be improved after applying the silvicultural treatments. There are significant differences in the stand diversity indices between before and after silvicultural treatments for each stand. According to the evaluation of stand diversity indices, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.