• Journal of the Korean Wood Science and Technology
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• 제44권6호
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• pp.890-896
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• 2016

Paulownia tomentosa is one of fast-growing wood species in Korea. In order to evaluate the solid bioenergy properties of Paulownia tree, this study examined the heating value, moisture content (MC), pH and proximate analysis of stem, branch, root, bark and leaf. The heating values of wood parts were slightly higher than those of bark and leaf, and that of branch was the highest among all the samples. The higher moisture content of bark and leaf referred to their lower heating value. Also, the pH of stem, branch and root was similar and lower than those of bark and leaf. The ash content of bark and leaf was much higher than that of wood parts, which is the one of the reasons for effect on the lower heating value and higher pH. While, the volatile matter content (VMC) of bark and leaf was lower than those of wood parts. The bark showed the highest fixed carbon content (FCC), while the FCC of stem was the lowest among all the samples. The obtained results are encouraging that the Paulownia tree could be totally utilized as alternative fuels for bioenergy production.

• 미생물학회지
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• 제30권6호
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• pp.450-455
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• 1992

대전 지역에서 자생하는 벌노랑이 (Lotus corniculatus var. japonicus) 의 뿌리혹으로부터 생장속도가 빠른 (fast-growing) 5균주를 분리하였다. 분리된 공생균주들은 형태적, 생리적 특성 및 뿌리혹형성 실험을 통하여 이 균주들은 Rhizobium loti 로 동정되었다. 분리균주로 접종시킨 벌노랑이 유식물에서 뿌리혹을 형성하였으며, 대조구와 비교하였을 때 정상적인 성장을 하는 것으로 보아 질소고정능을 갖는 (effect) 뿌리혹을 형성함을 알 수 있었다. 유도된 뿌리혹으로부터 재분리된 공생균주의 형태절 특성 및 항생제 내성에 대한 조사로부터 이들 뿌리혹은 1차 분리균주에 의해 형성된 것임을 알 수 있었다. 또한 이들은 Lotus corniculatus 에서도 질소고정능을 갖는 뿌리혹을 형성하였다. 분리균주 중 R. loti TUS2, TUS5 그리고 TUS8 은 calcofluor-binding exopolysaccharide(EPS) 를 생성하였다.

• Journal of Yeungnam Medical Science
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• 제31권1호
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• pp.48-51
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• 2014

Multiple symmetric lipomatosis (MSL) is a rare disease characterized by symmetrical massive fatty deposits on the face, neck, shoulders, and upper trunk. We report a 74-year-old man who complained of painless subcutaneous nodules on his posterior neck that developed 3 weeks earlier. In a week, variably-sized similar lesions developed on both his shoulders and upper extremities. At the time of his hospital visit, several firm nodules as big as a walnut to a child's fist and with the normal-skin-hue were observed on his posterior neck, both shoulders, upper extremities, and trunk. The histological examination of his upper left arm revealed more mature adipocytes without encapsulation in the subcutaneous tissue. MSL was generally known to occur slowly over months or years. However, this is an unusual case that showed a fast-growing nature.

• 한국방재안전학회논문집
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• 제13권2호
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• pp.1-9
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• 2020

베트남의 도시들은 지리적 특성으로 인해 기후변화에 따른 홍수 위험성이 높은 상황인데, 빠르게 도시지역이 확장됨에 따라 홍수위험성은 더욱 가중되고 있다. 본 연구에서는 도시확장강도지수를 활용하여 지난 10년간(2007년-2017년) 베트남 국가차원에서의 도시확장 추세를 확인한 후, 기후변화 영향이 크고 확장속도가 빠른 지역으로서 후에시를 선정하여 홍수발생가능성을 확인하였다. 그 결과 홍강델타, 메콩델타, 해안지역의 주요 도시 주변으로 확장되었으며, 후에시의 경우 확장속도가 빠른 지역일수록 예상침수면적이 높은 것으로 나타났다. 이는 향후에 홍수재해 위험성이 더욱 커질 수 있음을 의미한다. 재해취약성분석 제도 등 국내의 도시방재정책은 베트남 급성장지역에서 기후변화를 고려한 도시계획 수립 시 도움이 될 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권4호
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• pp.479-486
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• 2016

A previous genome-wide association study (GWAS) exposed histone deacetylase 2 (HDAC2) as a possible candidate gene for breast muscle weight in chickens. The present research has examined the possible role of HDAC2 in skeletal muscle development in chickens. Gene expression was measured by quantitative polymerase chain reaction in breast and thigh muscles during both embryonic (four ages) and post-hatch (five ages) development and in cultures of primary myoblasts during both proliferation and differentiation. The expression of HDAC2 increased significantly across embryonic days (ED) in breast (ED 14, 16, 18, and 21) and thigh (ED 14 and 18, and ED 14 and 21) muscles suggesting that it possibly plays a role in myoblast hyperplasia in both breast and thigh muscles. Transcript abundance of HDAC2 identified significantly higher in fast growing muscle than slow growing in chickens at d 90 of age. Expression of HDAC2 during myoblast proliferation in vitro declined between 24 h and 48 h when expression of the marker gene paired box 7 (PAX7) increased and cell numbers increased throughout 72 h of culture. During induced differentiation of myoblasts to myotubes, the abundance of HDAC2 and the marker gene myogenic differentiation 1 (MYOD1), both increased significantly. Taken together, it is suggested that HDAC2 is most likely involved in a suppressive fashion in myoblast proliferation and may play a positive role in myoblast differentiation. The present results confirm the suggestion that HDAC2 is a functional gene for pre-hatch and post-hatch (fast growing muscle) development of chicken skeletal muscle.

• 대한치과교정학회지
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• 제20권1호
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• pp.23-45
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• 1990

It is the aim of this study to determine the effects of facial denervation on physiological properties of facial muscles and facial bones in growing rabbits. Experimental animals of fifty two Oryctolagus cuniculus rabbits were employed. Unilateral dissection of facial nerve was carried out on twelve rabbits, bilateral dissection of facial nerve was made on another twelve rabbits and the other twenty rabbits were on unilateral dissection of facial nerve for the histochemical analyses. Six rabbits on the bilateral surgical sham operations and six rabbits of non-intervention served the control groups. EMG records of the orbicularis oris, buccinator and masseter muscles as well as lateral and dorsoventral cephalometric films were taken and analyzed at 0, 1, 2, 5 and 8 weeks respectively. The orbicularis oris, buccinator and masseter muscles of both sides were removed from the animals of the histochemistry group and muscle fibers were classified on the basis of histochemical staining for $\alpha$-GPD, NADH-D and myosin ATPase. EMG activities of orbicularis oris and buccinator muscles were vanished immediately after denervation. Recovery of activities were detected one week after denervation in buccinator and five weeks in orbicularis oris muscles. Histochemical properties of masseter muscles remained as fast glycolytic through the experimental period. Orbicularis oris muscle fibers showed the gradual diminution of size and ratio of the slow oxidative fibers accompanied with atrophy, phagocytosis and vacuolation as well as the augmentation of fast oxidative glycolytic fibers. The buccinator muscle manifested the augmentation of fast oxidative glycolytic fibers at five weeks of experiment. Visual changes in morphology of craniofacial area were not evident, however it variety of subtle changes were apparent from statistical analysis of cephalometric measurements. It is concluded facial nerve regulates the physiological properties of facial muscles and interrelation between the function of the facial muscles and changes of facial bones would be in some degrees.

• 미생물학회지
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• 제23권3호
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• pp.197-202
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• 1985

Glycine이 R.japonicum의 spheroplasting에 미치는 영향을 검토하였다. Fast-growing R. japonicum R-271은 4mg/ml의 glycine 함유배지에서 생육이 정상이었으나 세포 형태는 배양시간에 따라 변화하였으며 colony 형성단위는 log-phasedlgn 현저히 감소하였다. R-271은 3.5mg/ml glycine 함유배지에서 6시간 배양후에, slow grower R-214는 0.1mg/ml glycine 함유배지에서 24시간 배양후에 lysozyme의 작용을 받았다. 두 균주 모두 이러한 처리에 의해 96%이상의 spheroplast 형성빈도를 나타내었다. 한편 spheroid-type cell은 대두근의 nodule에서 분리한 bacteroid에서도 관찰되었으며 nodule extract에 존재하는 유리 amino acid 중 glycine 은 다른 amino acid에 비해 소량 존재하고 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제3권3호
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• pp.266-284
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• 2009

The challenges of rapidly growing numbers of mobile nodes in IPv6-based networks are being faced by mobile computing researchers worldwide. Recently, IETF has standardized Mobile IPv6 and Fast Handover for Mobile IPv6(FMIPv6) for supporting IPv6 mobility. Even though existing literatures have asserted that FMIPv6 generally improves MIPv6 in terms of handover speed, they did not carefully consider the details of the whole handover procedures. Therefore, in conventional protocols, the handover process reveals numerous problems manifested by a time-consuming network layer based movement detection and latency in configuring a new care of address with confirmation. In this article, we study the impact of the address configuration and confirmation procedure on the IP handover latency. To mitigate such effects, we propose a new scheme which can reduce the latency taken by the movement detection, address configuration and confirmation from the whole handover latency. Furthermore, a mathematical analysis is provided to show the benefits of our scheme. In the analysis, various parameters are used to compare our scheme with the current procedures, while our approach is focused on the reduction of handover latency. Finally, we demonstrate total handover scenarios for the proposed techniques and discussed the major factors which contribute to the handover latency.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2021년도 춘계학술대회
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• pp.33-42
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• 2021

Based on the findings of Lee et al.(2020) and Lee & Oh(2021), this paper aims to fill the gap in our knowledge regarding the relationship between strategic choices and corporate growth by utilizing a novel dataset of 'Unicorn' and 'Hyper-growing' companies. Two previous studies provide coherent findings that the relationship between firms' strategies and their performance should be explored under a more comprehensive framework with consideration of both internal and external factors. Therefore, in this study, we apply a single conceptual framework to two different datasets, which considers the strategy factors as independent variables, and the industry(market) and the firm age as moderating variables. For our dependent variables, valuations for unicorn companies and revenue CAGR for hyper-growing companies are used after categorizing them into three uniform groups. The strategy variables include 'Generic (Cost-leadership, Differentiation, focus) strategies', 'Growth(Organic, M&A) strategies', 'Leading(Pioneer, Fast-follower) strategies', 'Target market(B2B, B2C, B2G, C2C) strategies', 'Global(Global, Local) strategies', 'Digital(Online, Offline) strategies.' For industry(market) factors, it consists of historical growth rate for industries and economic, demographic, and regulatory aspects of states and countries. To overcome the differences in their units, they are also uniformly categorized into multiple groups. Before we conduct a regression analysis, we analyze the industry distribution of the 'Unicorn' and the 'Hyper-growing' companies with descriptive statistics at the integrated and individual levels. Next, we employ hierarchical regression models on Study A('Unicorn' companies in 2019) and Study B('Hyper-growing' companies in 2019) under the same comprehensive framework. We then analyze the relationship between the 'strategy' and the 'performance' factors with two different approaches: 1) an integrated regression model with both the sample of Study A and B and 2) respective regression models on Study A and B. This empirical study aims to provide a complete understanding and a reference to which strategy factors should be considered to promote firms' scale-up and growth.

• 벤처창업연구
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• 제16권2호
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• pp.51-78
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• 2021

'스케일업(scale-up)'은 '스타트업(startup)'에 이어 기업 현장이나 정책 현장에서 모두에서 중요한 주제로 다루어지고 있다. 특히 산업계와 정책 분야에서는 범용적으로 사용되는 용어임에도 불구하고, 학술적인 측면에서는 이에 대한 '개념 정의' 조차도 이루어지지 못했다. 학술적인 측면에서의 '기업 성장(firm growth)'과 경영 현장에서의 '비즈니스 성장(business growth)'은 서로 다른 이해를 갖고 있는 실정이다(Achtenhagen et al., 2010). 기업의 성장과 관련한 그간의 관련 연구는 Penrose(1959)의 '자원의 결합체(bundle)로서의 기업'과 '관리자의 역할론' 관점에서 크게 벗어나지 못하고 있다. 경제학 이론 및 배경을 기초로 주로 성장 요인 및 패턴을 살피는 차원에서의 연구가 주류를 이루고 있다. 기업의 경영현장에서 관심을 갖는 '스케일업' 맥락의 연구, 즉 상대적으로 성장의 속도와 지속성-일정기간의 '매출액 연평균 성장률'-관점의 연구는 활발히 이루어지지 못하였다. 기업의 초기 단계에는 매출액 규모가 작기 때문에 연간 단위 매출액 성장률은 상대적으로 높은 특성을 지닌다. 그러나, 한국 기준 '중견기업'으로 분류되기 시작하는 연간 매출액 1천억원 이상 수준이 되면 기업의 성장률은 이전과 같이 높은 수준을 보이기 쉽지 않다. 본 연구의 표본이 되는 최근 3년간의 연평균 매출액 성장률이 15% 이상 되는 '고성장 기업' 5천개 중 매출액 1억 달러 이상 기업은 6.7%인 333개에 한정된다. 그만큼 일정한 기업 규모 이상의 수준에서 지속적인 '고성장'을 보인다는 것은 쉽지 않다. 본 연구는, 기업/산업 미디어인 'Inc.'의 '2020 고성장(fastest-growing) 기업 5,000' 리스트 중 연간 매출액 1억 달러(원화 약 1천2백 억원) 이상 기업 333개를 대상으로, 1) 고성장 기업군(최근 3년-2016~19년- CAGR 15%~39.9%), 2) 초고성장 기업군(40.0%~99.9%), 3) 슈퍼 고성장 기업군(100% 이상)으로 구분 짓고, 각 성장속도 군 별 특성을 심층적으로 분석해 보았다. 또한, 기업의 매출액 성장률과 개별 기업의 전략 선택(시장 지향성, 본원적 전략, 성장 전략, 선도 전략), 산업 및 시장 환경, 기업의 업력 간의 상호관계를 양적 탐색을 통해 규명하였다. 따라서 본 연구결과를 토대로 개별 기업의 측면에서는 성장전략의 경로와 요인을 조합하여 구성하는 '초고성장 모델(Hyper-Growing Model)'을 참고할 수 있도록 하고, 정책적인 측면에서는 기업의 성장을 촉진하기 위해 어떤 요소나 환경을 '최적 유효 조합'의 형태로 다루어야 하는지 그 참고를 제공하고자 한다. 그리고 학술적인 측면에서는 21세기 기업환경에서 '스케일업 이론' 및 '기업 성장 이론'을 후속적으로 연구 하는데 그 기초 참고를 제공하고자 한다.