• 전자공학회논문지CI
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• 제41권4호
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• pp.9-21
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• 2004

본 논문은 동영상내의 객체를 자동으로 추출하고 추적할 수 있는 유전자 알고리즘 기반의 분할 방법을 제안한다. 제안된 방법은 시간 분할과 공간 분할로 이루어진다. 공간 분할은 각 프레임을 정확한 경계를 가진 영역으로 나누고 시간 분할은 각 프레임을 전경 영역과 배경 영역으로 나눈다. 공간 분할은 분산 유전자 알고리즘을 이용하여 수행된다. 그러나, 일반적인 유전자 알고리즘과는 달리, 염색체는 이전 프레임의 분할 결과로부터 초기화되고, 동적인 객체 부분에 대응하는 불안정 염색체만이 진화연산자에 의해 진화된다. 시간 분할은 두 개의 연속적인 프레임의 밝기 차이에 기반을 둔 적응적 임계치 방법에 의해 수행한다. 얻어진 공간과 시간 분할 결과의 결합을 통해서 객체를 추출하고, 이 객체들은 natural correspondence에 의해 전체 동영상을 통해 정확히 추적된다. 제안된 방법은 다음의 두 가지 장점을 가진다. 1) 제안된 비디오 분할 방법은 사전 정보를 필요로 하지 않는 자동 동영상 분할 방법이다. 2) 제안된 공간 분할방법은 기존의 유전자 알고리즘보다 해공간의 효율적인 탐색을 제공할 수 있을 뿐만 아니라, 정확한 객체 추적 메커니즘을 포함하고 있는 새로운 진화 알고리즘이다. 이러한 장점들은 제안된 방법이 잘 알려진 동영상과 실제 동영상에 성공적으로 적용됨을 통해 검증된다.

• Applied Microscopy
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• 제22권2호
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• pp.97-117
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• 1992

In order to study process of spermiogenesis of the Korean greater horseshoe bat, Rhinolophus ferrumequinum korai, the cycle of seminiferous epithelium was examined by the light and electron microscope and the following results were obtained based on the epithelial cell differentiation. 1. Spermiogenesis occurred from early July to mid-Octber, and spermatogenic activity was vigorous from mid-August to late September. Spermatocytes including spermatogonia were found to be degenerated in only July. It is deduced that the degeneration serves as the mechanism to regulate effective use of energy to prepare for mating and hibernating periods, and regulation of breeding cycle. 2. Spermiogenesis of the Korean greater horseshoe bat was divided according to differentiation of the cell structure, into Golgi, cap, acrosome, maturation and spermiation phases; Golgi, cap and spermiation phases were further divided into two steps of early and late phase respectively, and acrosome phase into three steps of early, mid and late phases, and maturation phase has only one step. Hence, the spermiogenesis consists of ten phases. The first research was done in this article on the changes of chromatin with nucleus, the time of appearance and disappearance of chromatin granules, in case of Korean greater horseshoe bat (Rhinolophus ferrumequinum korai). Chromatin granule began to be condensed in late Golgi and the condensation proceeded to form an irregular mass of a electron-dense chromatin in a form of circular cylinder in the center of nucleus at the phase of maturation. Finally, the chromatin condensation proceeded and perfect nucleus of sperm with homogeneous density was formed when the sperm was separated from Sertoli cell. Therefore, appearance and disappearance of chromatin granules occurred in the period of time between late Golgi and maturation phase, The tail of sperm began to develop in early cap phase, Numerous lipid droplets were obseved in the cytoplasm of spermatids during the maturation phase, which seemed to be used as energy source necessary to make mature sperm during spermiogenesis.

• 한국양식학회지
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• 제6권4호
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• pp.235-253
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• 1993

동남참게, Eriocheir japonicus의 인공 채란 방식을 확립시키기 위하여 1990년11월-1991년7월까지 경남 하동군 섬진강 하구역에서 채집한 자웅성체를 사육하면서 교미로부터 산란 및 포난까지에 소요되는 시간, 난발생과 부화에 따른 온도와 염분농도와의 관계 등 생물학적 기초과제를 조사한 결과는 다음과 같다. 교미로부터 산난개시까지에 소요되는 시간은 2-8시간이 걸리고, 산난개시로부터 포난이 완료될 때까지에는 대체로 3-9시간이 소요되며 난은 포난실내에서 체외수정을 한다. 인위적인 교미 조절에 의해 연간 최소한 4-6회의 산란을 시킬 수 있었으며, 포란수는 흉갑장의 길이가 6cm인 경우에는 대체로 $38\~41{\times}10^4$위 정도이다. 포란한 어미게의 부화에 따른 호적한 수온 및 염분농도는 각각 $17\~23^{\circ}C,\;14.0\~3l.5\%o$ 범위였다. 산란 개시로부터 부화까지에 달하는 소요일수는 수온 $14^{\circ}C$ 일때 42일, $17^{\circ}C$ 일때 28일, $20^{\circ}C$일때 21일 $26^{\circ}C$일 때 15일 그리고 $28^{\circ}C$ 14일이 소요되며, 수온(X)과 부화일수 (Y)와의 관계는 Log Y=Log 3.267-1.602 Log X의 식으로 표시된다. 수온 $18^{\circ}C$, 염도 $24.5\%o$ 조건하에서 란발생 진행과정은 산란후 7일이 지나면 배체가 형성되고 18일 만에는 복안이 형성되며 22일째가 되면 복절부의 굴신동작이 간헐적으로 일어나게 되어 25일째에 zoea 상태로 부화하게 된다.

• 헤리티지:역사와 과학
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• 제56권1호
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• pp.132-140
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• 2023

본 연구는 천연기념물인 남생이(Mauremys reevesii)의 암컷과 수컷의 성적 이형성의 특징을 알아보기 위해 총 21마리의 남생이를 머리, 배갑(Carapace), 복갑(Plastron)의 21개의 부위를 머리길이(HL)와 배갑길이(CL)를 기준으로 총 19개 부위의 비율 값을 도출하였다. 비율 값을 비교한 결과 남생이 수컷은 암컷보다 머리길이, 머리폭, 머리높이가 더 크고, 배갑과 복갑의 경우 모든 측정부위에서 암컷이 수컷보다 큰 것을 알 수 있었다. 암컷은 짝짓기 후 체내 수정을 통해 산란 전까지 체내에서 알을 성장시키기 때문에 암컷이 전체적으로 수컷보다 큰 것으로 판단된다. 측정된 수치의 비율 값을 통계 분석한 결과, 복갑길이(PL), 골교길이(BL), 후갑판길이(GL), 견갑판길이(IH), 항갑판길이(IAN), 고-항갑판길이(FA), 머리높이(HH)에서 통계적으로 유의한 차이를 보였다. 복갑의 부위에서 통계적으로 유의한 것으로 보아 남생이는 성장함에 따라 복갑의 각 갑판에 직접적으로 작용하는 것으로 판단된다. 또한, 남생이 수컷의 머리 크기는 암컷 보다 작지만 비율적으로 봤을 때 더 큰 것을 알 수 있었다. 남생이는 교미 전 수컷이 머리를 흔들며 구애행동을 하는 습성으로 인해 체구에 비해 오히려 머리가 더 큰 것이라 사료된다. 이번 연구를 통해 남생이의 성적 이형성 특징을 파악할 수 있었다. 하지만 대부분 구조된 개체가 대부분이기 때문에 서식환경과 연령을 정확히 파악할 순 없었다. 추후 서식지와 연령이 명확한 개체를 대상으로 추가적인 연구를 진행한다면 성장하면서 발달하는 신체적 차이에 관한 특징을 규명할 수 있을 것으로 보인다.

• Journal of Forest and Environmental Science
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• 제28권1호
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• pp.1-7
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• 2012

Tropical forests whether fragmented or undisturbed or be they equatorial or deciduous, remain the storehouse of biodiversity for hundreds of thousands of plant and animal species. This unique characteristic continues to attract a wide range of scientists and international organizations to study and attempt to understand tropical forest ecosystems. Gene flow is mediated by pollen, seed and seedling dispersal, and factors affecting this gene flow include phenology, spatial distribution, population structures, seed predation, sexual and mating systems as well as physical and biological barriers to gene flow. Two methods are used in measuring gene flow: direct method that relies on the actual observation of seed and pollen dispersal, whereas indirect methods involve the use of genetic markers such as allozymes and DNA techniques. Political strife, extreme natural and artificial disasters, the lack of a comprehensive forestry research vision, coupled with difficult socio-economic conditions in Africa have made the environment quite difficult for sustained research activities on the part of those undertaking or wishing to undertake such studies. Gene flow studies in this region are few and far between. This review elaborates on the mechanisms of gene flow mediation in Sub-Saharan Africa.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.145-148
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• 2009

To understand whether experience of cold season in reproductive behaviors in the adults of Amaurobius ferox, the paired adults of a female and a male were exposed under 'cold-treated environment' and 'not cold-treated environment', respectively. I investigated effects of the cold treatment on the brood production of A. ferox. In not cold treatment in which male-female pairs were formed in October at a temperature of $20^{\circ}C$ (${\pm}2^{\circ}C$) and continuously kept under not cold-treated environment, only 3 of 50 pairs successfully reproduced (reproduction was defined as the emergence of spiderlings). In cold treatment where individuals were kept in cold conditions for 3 months prior to pair formation, 57 out of 60 couples succeeded in reproducing. Females which did not experience the low temperature displayed strong aggressiveness toward males. This behavioral inhibition might the primary barrier to copulation of A. ferox that decrease following a period of low temperature. The reproductive inhibition might help the females to allocate the maximum amount of energy in a given environment to reaching the adult stage and to delay reproduction in unfavorable wintering conditions.

• Asian-Australasian Journal of Animal Sciences
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• 제26권7호
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• pp.916-920
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• 2013

The triploid Pacific oyster, which is produced by mating tetraploid and diploid oysters, is favored by the aquaculture industry because of its better flavor and firmer texture, particularly during the summer. However, tetraploid oyster production is not feasible in all oysters; the development of tetraploid oysters is ongoing in some oyster species. Thus, a method for ploidy verification is necessary for this endeavor, in addition to ploidy verification in aquaculture farms and in the natural environment. In this study, a method for ploidy verification of triploid and diploid oysters was developed using multiplex polymerase chain reaction (PCR) panels containing primers for molecular microsatellite markers. Two microsatellite multiplex PCR panels consisting of three markers each were developed using previously developed microsatellite markers that were optimized for performance. Both panels were able to verify the ploidy levels of 30 triploid oysters with 100% accuracy, illustrating the utility of microsatellite markers as a tool for verifying the ploidy of individual oysters.

• 소음진동
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• 제5권4호
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• pp.565-575
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• 1995

Gearboxes are often used in the petrochemical and electrical power plants to transmit mechanical power between two branches of a machinery train rotating at different speeds. When the gearboxes are connected with rotors supported by journal bearings, bearing loads vary in magnitude and direction with rotor speed and torque transmitted by the gearboxes. In this study, dynamic characteristics of the system which consists of gearboxes and a rotor supported by journal bearings are investigated analytically and experimentally by employing the polynomial transfer matrix method and modal analysis under different speeds and torque levels. Journal bearing loads due to the transmitted torque are claculated analytically and the stiffness and damping coefficient of the journal bearings are obtained using finite element method. Comparison of the analytical and experimental results shows that the cross coupled stiffness coefficients increase with increasing rotor speed, while the cross coupled damping coefficients decrease. This generates the oil whirl instability in the journal bearings. As the transmitted torque level goes up, the stiffness coefficients of the journal bearing and the first horizontal natural frequency increase. High levels of the transmitted torque produce high bearing stiffness since the contact loads of the mating gear teeth increase. The logarithmic decrement, which is a stability indicator, is shown to decrease with increasing speed and decreasing torque. Thus, at the low torque level, the system become unstable even at the low shaft speed.

• Mycobiology
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• 제33권3호
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• pp.125-130
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• 2005

Pigmentation of ascospore-derived isolates from seven different natural specimens of Cordyceps militaris EFCC C-5888, EFCC C-7159, EFCC C-7833, EFCC C-7991, EFCC C-8021, EFCC C-8023 and EFCC C-8179 was observed on the plates of Sabouraud Dextrose agar plus Yeast Extract at $25^{\circ}C$ under continuous illumination (500 lux). Pigmentation of the wild-type isolates of C. militaris was diverse ranging from yellowish white to orange, while white color was believed as a mutant. Inheritance of pigmentation was found to be controlled by both parental isolates when F1 progeny were analyzed. Pigmentation and mating type were shown to be either independent or distantly linked each other due to the high percentage of non-parental phenotypes among F1 progeny. Crosses between white mutant isolates of C. militaris yielded progeny with wild type pigmentations, indicating that the albino mutations in the parents were unlinked to each other.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.569-582
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• 2004

Current growth in the deer industry is 20% per annum as the demand increases for venison in Europe, including the increased use in Asia of antlers as a natural medicine by humans. The deer industry in Australia has developed rapidly, but farm profitability has fluctuated markedly. The knowledge on deer farming has largely been adopted from New Zealand (NZ) and the United Kingdom (UK) although the environmental conditions in these deer growing countries differ markedly from Australia. The practice used for weaning is one of the key factors influencing the profitability of the industry. However, a wide range in weaning dates are practised by farmers leading to the question of whether deer should be weaned after mating to reduce the stress during weaning or should they be weaned in the pre-rut period to allow does to recover their body condition for the next reproduction cycle. This review examines the effect of weaning time on the performance of does and hinds and the subsequent growth rate of the fawns and calves. Gaps in knowledge of weaning procedures and nutritional management for early weaned deer are identified.