• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.9-12
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• 2000

Today, QoS is one of the most critical issues in the network research area and Differentiated Services (DiffServ) is considered as the most prominent solution to provide some kinds of service differentiation without introducing any scalability problem. Among DiffServ's approaches, Assured Service (AS) provides some minimal level of QoS guarantee by treating more preferably than traditional Best Effort (BE) traffic and by using different level of drop probabilities within the same AS classes. In this paper, we investigate the ECN's capability of improving overall goodput of the flows and the possibility of resolving the fairness problem among the flows belonging to same class in Differentiated Services architecture.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.102-105
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• 1997

In cultivating human neuroblastoma cells maximum number of neurites per cell and length of the neurite were estimated as 5.5 and 2.2 (nm), respectively It was found that there was correlation between growth and differentiation of nerve cells. Maximum specific BDNF production rate was also calculated as 2.5$\times $10$^{-5}$(ng/cell/day) at 7$\times $ 10$^{5}$ (viable cells/ml) of maximum cell density, corresponding to 100 (ng/mL) of BDNF. The secretion of BDNF was occurred most in the later peroids of the cultivation, yielding 75 (ng/mL) of BDNF. The production of rate of BDNF was elongated in adding 1 ($\mu $g/mL) of BDNF as well as 40% increase of the length of the BDNF. It proves that BDNF can be used as one of biopharmaceuticals to treat age-related diseases such as Alzheimer's disease and Prakinson's disease. It can also provide the information of scaling-up mammalian cell cuture system to economically produce BDNF.

• 전자공학회논문지B
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• 제33B권4호
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• pp.131-140
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• 1996

In this paper, we propose the method that extracts the speech feature using the hearing model through signal precessing techniques. The proposed method includes following procedure ; normalization of the short-time speech block by its maximum value, multi-resolution analysis using the discrete wavelet transformation and re-synthesize using thediscrete inverse wavelet transformation, differentiation after analysis and synthesis, full wave rectification and integration. In order to verify the performance of the proposed speech feature in the speech recognition task, korean digita recognition experiments were carried out using both the dTW and the VQ-HMM. The results showed that, in case of using dTW, the recognition rates were 99.79% and 90.33% for speaker-dependent and speaker-independent task respectively and, in case of using VQ-HMM, the rate were 96.5% and 81.5% respectively. And it indicates that the proposed speech feature has the potentials to use as a simple and efficient feature for recognition task.

• BMB Reports
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• 제51권11호
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• pp.547-548
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• 2018

Phloem network integrates cellular energy status into post-embryonic growth, and development by tight regulation of carbon allocation. Phloem development involves complicated coordination of cell fate determination, cell division, and terminal differentiation into sieve elements (SEs), functional conduit. All of these processes must be tightly coordinated, for optimization of systemic connection between source supplies and sink demands throughout plant life cycle, that has substantial impact on crop productivity. Despite its pivotal role, surprisingly, regulatory mechanisms underlying phloem development have just begun to be explored, and we recently identified a novel translational regulatory network involving RNA G-quadruplex and a zinc-finger protein, JULGI, for phloem development. From this perspective, we further discuss the role of RNA G-quadruplex on post-transcriptional control of phloem regulators, as a potential interface integrating spatial information for asymmetric cell division, and phloem development.

• BMB Reports
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• 제51권11호
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• pp.549-556
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• 2018

Mitochondria are ubiquitous and multi-functional organelles involved in diverse metabolic processes, namely energy production and biomolecule synthesis. The intracellular mitochondrial morphology and distribution change dynamically, which reflect the metabolic state of a given cell type. A dramatic change of the mitochondrial dynamics has been observed in early development that led to further investigations on the relationship between mitochondria and the process of development. A significant developmental process to focus on, in this review, is a differentiation of neural progenitor cells into neurons. Information on how mitochondria-regulated cellular energetics is linked to neuronal development will be discussed, followed by functions of mitochondria and associated diseases in neuronal development. Lastly, the potential use of mitochondrial features in analyzing various neurodevelopmental diseases will be addressed.

• 한국발생생물학회지:발생과생식
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• 제17권2호
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• pp.87-97
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• 2013

The seminiferous epithelium cycle and developmental stages of spermatids in Clethrionomys rufocanus were observed under a light microscope. The seminiferous epithelium cycle was divided into 8 stages. Type Ad spermatogonia appeared through all stages. Type Ap, In, and B spermatogonia appeared in stages I, II, III, and IV. In the first meiosis prophase, the leptotene spermatocytes appeared from stage V, the zygotene spermatocytes in stages I, VI, VII, VIII, the pachytene spermatocytes from stages II to VI, the diplotene spermatocytes in stage VII. The meiotic figures and interkinesis spermatocytes were observed in stage VIII. Developing spermatids were subdivided into 10 steps, based on the morphological characteristics such as the acrosome formation changes in spermatozoa, nucleus, cytoplasm, and spermiation changes. The C. rufocanus spermatocytogenesis and spermiogenesis results displayed similar results with Apodemus agrarius coreae and A. speciosus peninsulae. Considering all the results, the spermatogenesis may be useful information to analyze the differentiation of spermatogenic cells and the breeding season.

• Molecules and Cells
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• 제41권4호
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• pp.264-270
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• 2018

Cells cope with diverse intrinsic and extrinsic stimuli in order to make adaptations for survival. The epigenetic landscape plays a crucial role in cellular adaptation, as it integrates the information generated from stimuli. Signaling pathways induced by stimuli communicate with chromatin to change the epigenetic landscape through regulation of epigenetic modifiers. Metabolic dynamics altered by these stimuli also affect the activity of epigenetic modifiers. Here, I review the current understanding of epigenetic regulation via signaling and metabolic pathways. In addition, I will discuss possible ways to achieve specificity of epigenetic modifications through the cooperation of stimuli-induced signal transduction and metabolic reprogramming.

• 한국멀티미디어학회논문지
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• 제10권12호
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• pp.1622-1631
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• 2007

To realize the wireless packet scheduler which efficiently considers both the effect of adaptive modulation and coding (AMC) scheme due to variable wireless communication channel information from physical layer and the QoS differentiation of multimedia services from internet protocol (IP) layer, this paper proposes a new downlink AMC-based priority queuing (APQ) scheduler which combines AMC scheme and service priority method in multimedia services at the same time. The result of numerical analysis shows that the proposed APQ algorithm plays a role in increasing the number of services satisfying the mean waiting time requirements per each service in multimedia services because the APQ scheme allows the mean waiting time of each service to be reduced much more than existing packet scheduler having only user selection processor.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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• pp.6-9
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• 2008

A 3D depth measurement system is proposed for mobile vehicles. Depth measurement system which is composed of a rotating mirror, a line laser and mono-camera is employed to detect depth, where the laser light is reflected by the mirror and projected to- the scene objects whose locations are to be determined. The obtained depth information is converted into an image. Such depth images of the road region represent even and plane while that of off-road region is irregular or textured. Road region is detected employing a simple spatial differentiation technique to detect the plain textured area. Identification results of the diverse situation of Non-linear trail are included in this paper.

• Clinical and Experimental Reproductive Medicine
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• 제39권2호
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• pp.41-45
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• 2012

Transcription factors govern diverse aspects of cell growth and differentiation as major switches of gene expression. Etv5, a member of the E26 transformation-specific family of transcription factors, has many stories to share when it comes to reproduction. Etv5 deficient mice show complex infertility phenotypes both in males and females. In males, the infertility phenotype exhibited by Etv5 deficiency is sexually dimorphic, and it involves both somatic cells and germ cells. In $Etv5^{-/-}$ female mice, the problem is more complicated by hormonal involvement. This review synthesizes old and new information on this versatile transcription factor-from the inadvertent discovery of its role in the testes to its newly discovered role in maintaining spermatogonial stem cells.