• 한국가구학회지
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• 제20권2호
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• pp.136-142
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• 2009

Hoein Hyanggyo is a confucian shrine at Hoein, Boeungun, Chungbuk, Korea. Using tree rings, we dated its lecture hall, Myengryundang which is a two-storied wooden structure with half-gabled and half-hipped roof. The woods of Myengryundang consisted mainly of lard pine (probably, Pinus densiflora). We collected 27 samples (4 columns, 2 beams, 5 purlins, 4 capitals, 8 floor frames/boards and 4 others). The results indicated that the major cutting year was A.D. 1702. This date helped to correct the miswritten Chinese-calender date which was recorded in the document for the framework-raising ceremony.

• Journal of Biosystems Engineering
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• 제27권5호
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• pp.399-408
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• 2002

The sweet persimmons are producted 227,394 tons per year in Korea. They are preserved at cold storage after wrapping them in packing vinyl to maintain quality. Using conventional handwork, a skillful worker could probably produce only 1,000 packings a day. Hiring many skilled-labors to wrap sweet persimmons in packing vinyl seems to be difficult because of the recent rural crisis. Therefore, it was necessary to be developed for the automated ordering and packing unit that is convenient and laborsaving. This study were summarized as follows : Success rates of 99%, 100%, and 88% were observed for ordering parts, sealing and cutting films, and sealing films in the inlet part, respectively. The time required per 1 cycle was 16 seconds and the developed unit performed 225 cycles an hour. The unit showed an ability of 1,125 pieces per hour. Therefore, the productivity was 10 times greater than that of skillful handwork.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.337-349
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• 2009

In recent years, the cutting and banking areas along the railway in Korea are exposed to the erosion problem during every year. The reinforcement is a composite construction material in which the strength of engineering fill is enhanced by the addition of strong tensile reinforcement in many different types. Various problems of the railway infrastructure have occurred due to the differential settlement, frost heaving, mud pumping, lack of bearing capacity, partially loss of embankment. In advanced countries, railway roadbed reinforcement is applied to solve these problems on railway roadbed. This paper presents the solution of such problems by means of the engineering works incorporated with railway reinforcement infrastructures such as geotextile bag method, existing grouting method, geocell, reinforced earth, soil nailing and so on.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.168-179
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• 1982

The first step to utilize the growing resources of Italian poplar (Populus euramericana I-476) for pulp-Woods, its characteristics and adaptabilities to the pulp industry must be investigated completely. The plantation methods are important for its fast growing in stock, and no less important is the cutting age for its utilization as pulpwood. In this paper, the stone groundwood pulping, refiner groundwood pulping and chemi-groundwood pulping characteristics by the age of tree, along with their physical and chemical characterstics were tested, and relationships between the age groups were analyzed to find out the optimum felling age. The results obtained are as follows: 1. The coefficient of pliability was a little higher in the case of younger trees. 2. The water retention value of each pulp was directly proportional to its physical strength, but this tendency was not detected between the age groups of sample woods. 3. Generally, the physical strength of younger wood pulp was lower regardless of the pulping process. But in the case of pretreatment with NaOH, Asphund and CGP pulp from 5 year old sample wood were stronger in physical strengths than those of GP and Asplund pulp with no pretreatment from 10 years old sample wood. 4. The tear factor of Asplund pulp with alkali pretreatment was higher than that of CGP pulp but the breaking length and the burst factor was similar in all processes. Considering the pulp yield and its brightness, CGP process seems to be advantageous. 5. The dissimilarity of physical strength between 7 and 10 years old wood pulp was not very large in all pulping processes but the physical strength of 5 year old wood pulp was very weak. In the of groundwood pulping from Italian poplar woods, 5 year old wood pulp should be mixed with other long fiber pulp for making a good paper.

• 한국약용작물학회지
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• 제9권3호
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• pp.220-224
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• 2001

약용작물은 재배 환경이나 재배 년수, 생육 시기, 부위별로 약리성분 함량에 차이가 많은데, 본 연구에서 해독, 소종, 소변불리, 간염, 황달 등의 치료에 효과가 있는 삼백초를 퇴비시용량과 재배방법을 달리하여 생육상황, 수량 및 유효성분 함량을 분석한 결과는 다음과 같다. 삼백초는 퇴비 시용량이 증가할수록 지상부 생체수량이 높았으며, 유효성분으로 quercetin, quercitrin 및 tannin 함량을 분석한 결과 퇴비 2,000kg/10a 처리시 가장 높았다. 예취 회수별 지상부 수량은 년 1회와 2회 수확간 차이가 없었으며, 유효성분 함량은 년 2회 수확하였을 때 7월 16일에 비해 10월 16일 수확시 함량이 높았다. 재배방법별로는 노지재배시 하우스재배에 비해 지상부 생체수량은 낮았지만 quercetin, quercitrin 및 tannin 함량은 높았다.

• 한국자원식물학회지
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• 제15권2호
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• pp.107-113
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• 2002

본 연구는 외래도입 병솔꽃나무(Callistemon citrinus)의 개화결실 습성과 효율적인 증식방법을 구명 하고자 수행하였다. 병솔꽃나무의 삭과는 개화후 4년간 가지에 존속하며, 종자의 수와 크기는 3년생 삭과와 2년생 삭과가 비슷한 반면 1년생 삭과는 크게 차이가 나는 것으로 나타났다. 삭과로부터 종자를 탈리시키기 위해 건조시킨 결과 삭과의 상대 수분함량이 약 75%일 때 삭과열개율이 100%에 달했다. 발아율은 3$0^{\circ}C$에서 건조시킨 종자가 가장 높았으며, 그 중 2년생 삭과에서 탈리된 종자의 발아율이 높았다. 반면 50, 7$0^{\circ}C$에서 건조되어 탈리된 종자의 발아율은 낮았다. 가을철 2차 개화를 유도하기 위하여 봄철 개화 후 삭과가 달린 가지를 전정한 개체에서는 모든 개체에서 가을에 개화하였으며 , 개화량은 평균 14송이였다. 반숙지를 IBA 100mgι$^{-1}$ 에 24시간 침적처리한 결과 86.4%가 발근되었으며, 평균 12.6개의 1차근을 가지며 생장이 가장 양호하였다.

• 한국초지조사료학회지
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• 제12권3호
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• pp.153-160
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• 1992

본 시험은 고령지 두과목초의 적응성을 구명하기 위하여 표고가 다른 3개지역(600,800,1000m a.s.l)에서 주구를 파종시기(추파.추파), 세구를 혼파조명(알팔파-화본과, 레드크로바-화본과, 화이트크로바-화본과)으로 두고 분할구 배치 3반복으로 수행하였다. 1.600m에서 두과목초의 적응성을 보면 알팔파, 레드클러버 및 화이트클로버 공히 추파를 했을 때 연차간 악화없이 약 30%를 유지하여 적응성이 매우 양호하였다.2. 800m에서는 화치트클로버를 춘파하므로써 연차간에 심한 감소없이 최종 예취시 약 14.0%를 점유하고 있었으며 또한 10a당 건물수량이 가장 많았다. 3. 1000m에서도 800m와 비슷한 경향으로 화이트클로버를 춘파했을 경우 어느정도 적응이 가능하였다. 4. 표고별 두과목초의 비솔 및 수량이 표고가 증가 할수록 현저하게 감소하였으며 알팔파는 800m 이상에서는 생육이 거의 불가능하였다.

• 화훼연구
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• 제19권4호
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• pp.202-205
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• 2011

히어리 대량급속증식법의 기초를 마련하기 위해, 발근촉진제의 처리가 히어리 삽수의 발근에 미치는 영향을 살펴보았다. 삽수는 6~8년생 실생 히어리로 부터 채취하였으며, 발근촉진제로는 IBA용액, 루톤분의제 등을 이용하였다. 1차년도의 실험의 결과, 3월 20일 숙지삽목에서는 발근촉진제의 효과가 없었다. 6월 20일 녹지삽의 경우에는 IBA $100mg{\cdot}L^{-1}$ 용액 24시간 침적처리구에서 발근력이 가장 좋았다. 특히, 경시조사결과 IBA $100mg{\cdot}L^{-1}$ 24시간 침적처리구에서는 발근속도가 현저하게 빨라졌다. 2차년도의 실험의 결과에서는 IBA $200mg{\cdot}L^{-1}$ 용액 24시간 침적처리구에서는 삽목 30일만에 거의 모든 개체가 발근(97.8%)하였으며 발근수나 발근장도 타처리구에 비해 월등히 좋았다.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1098-1113
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• 2021

Maturation process of alfalfa (Medicago sativa L.) could be prevented by the reduction of lignin content in terms of conventional breeding or transgenic technology. Alfalfa could exhibit higher leaf/stem ratio, with a concern of yield loss. The objective of this study was to compare forage yield and nutritive value of low lignin alfalfa and two reference varieties subjecting to two harvest intervals and three seeding rates. The experimental design was a randomized complete block in a split-split plot arrangement with four replicates, where harvest intervals (28-day and 35-day) were assigned to whole plots, seeding rates were subplots, and varieties were sub-subplots. The weighted mean nutritive value was applied to two production years of 2016 and 2017. Hi-Gest 360 (low lignin alfalfa) provided similar yield potential and increased nutritive value compared to two reference varieties. Over a two-year production period, alfalfa harvested at every 28-day interval provided more economic returns than those at 35-day interval. For the seeding year and first production year, five cuts made by the 28-day interval produced more yield than four cuts by the 35-day interval. Due to limited rainfall in May 2017, a sharp drop of the first cutting overturned the advantage of the five-cut system. Shorter intervals between harvests generally increased crude protein (CP) concentrations. The differences of relative feed value (RFV) between two harvest intervals tended to be great during the first and second cuttings. Overall, harvest interval had a large effect on nutritive value and a more significant effect on alfalfa dry matter yield than variety selection. Seeding rate did not affect alfalfa yield and nutritive value.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권5호
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• pp.292-296
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• 2022

Objectives: During Le Fort I osteotomy, the separation of the pterygomaxillary junction (PMJ) is a difficult procedure for most surgeons because it is invisible. In this process, damage to the posterior structures constituting the sinus or those adjacent to it, including the maxillary sinus posterior wall and pterygoid plate, may occur. We would like to investigate the effects of this on the inside of the maxillary sinus after surgery and whether there are complications. Materials and Methods: One-hundred patients who underwent Le Fort I osteotomy from 2013 to 2020 using cone-beam computed tomography images were classified into two groups (clean-cut type and fractured type) according to the PMJ cutting pattern. In addition, the mucosal thickness in the maxillary sinus was divided into preoperative, postoperative three months, one year, and the change over the course of surgery was evaluated retrospectively. Results: Of the total 100 cases, the clean-cut type numbered 28 cases and the fractured type totaled 72 cases. Among the fracture types, part of the sinus wall and the pterygoid plate were broken in 69 cases, and the maxillary sinus posterior wall was detached in three cases. There was no statistically significant difference in sinus mucosal thickening between the clean-cut type and fractured type of the PMJ, three months and one year after surgery between the two groups. However, there was a significant difference in sinus mucosal thickness at postoperative one year in the case where a partial detachment of the maxillary sinus posterior wall occurred compared to not. Conclusion: Even if there is some damage to the structures behind the PMJ, it may not be reasonable to spend some time on the PMJ separation process considering the overall postoperative complications, if there is no significant difference inside the sinus, or increased probability of postoperative complications.