• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.959-961
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• 2004

A multi pole SRM(switched reluctance motor) is applied by the regulated current in regular sequence. So, it can be started by itself. But a single phase SRM can not be started by itself because the positive torque is only generated in the limited zone which the inductance is increased. Therefore, it is required auxiliary device for self starting which place the rotor in start position. The prototype was designed and fabricated in the previous research. It has the permanent magnet, which is installed in the bottom of the rotor, for self starting. But the permanent magnet affect the prototype during operation and cause the decrease of the torque and speed. The influence of the permanent magnet on the average torque and speed was already confirmed. On this paper, the instant torque of the prototype was calculated from the experiment results which is the inductance and current according to installed permanent magnet or not.

• BMB Reports
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• 제54권7호
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• pp.335-343
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• 2021

Cancer stem cells (CSCs) are a subpopulation of cancer that can self-renew and differentiate into large tumor masses. Evidence accumulated to date shows that CSCs affect tumor proliferation, recurrence, and resistance to chemotherapy. Recent studies have shown that, like stem cells, CSCs maintain cells with self-renewal capacity by means of asymmetric division and promote cell proliferation by means of symmetric division. This cell division is regulated by fate determinants, such as the NUMB protein, which recently has also been confirmed as a tumor suppressor. Loss of NUMB expression leads to uncontrolled proliferation and amplification of the CSC pool, which promotes the Notch signaling pathway and reduces the expression of the p53 protein. NUMB genes are alternatively spliced to produce six functionally distinct isoforms. An interesting recent discovery is that the protein NUMB isoform produced by alternative splicing of NUMB plays an important role in promoting carcinogenesis. In this review, we summarize the known functions of NUMB and NUMB isoforms related to the proliferation and generation of CSCs.

• The Korean Journal of Physiology and Pharmacology
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• 제27권2호
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• pp.187-196
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• 2023

Transient receptor potential canonical (TRPC) channels are non-selective calcium-permeable cation channels. It is suggested that TRPC4β is regulated by phospholipase C (PLC) signaling and is especially maintained by phosphatidylinositol 4,5-bisphosphate (PIP₂). In this study, we present the regulation mechanism of the TRPC4 channel with PIP₂ hydrolysis which is mediated by a channel-bound PLCδ1 but not by the G_qPCR signaling pathway. Our electrophysiological recordings demonstrate that the Ca²⁺ via an open TRPC4 channel activates PLCδ1 in the physiological range, and it causes the decrease of current amplitude. The existence of PLCδ1 accelerated PIP₂ depletion when the channel was activated by an agonist. Interestingly, PLCδ1 mutants which have lost the ability to regulate PIP₂ level failed to reduce the TRPC4 current amplitude. Our results demonstrate that TRPC4 self-regulates its activity by allowing Ca²⁺ ions into the cell and promoting the PIP₂ hydrolyzing activity of PLCδ1.

• BMB Reports
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• 제42권2호
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• pp.65-71
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• 2009

Autophagy, which is a process of self eating, has gained interest in the past decade due to its both beneficial and controversial roles in various biological phenomena. The discovery of autophagy genes (ATG) in yeast has led to focused research designed to elucidate the mechanism and regulation of this process. The role of autophagy in a variety of biological phenomena, including human disease, is still the subject of debate. However, recent findings suggest that autophagy is a highly regulated process with both beneficial and negative effects. Indeed, studies conducted using various model organisms have demonstrated that increased autophagy leads to an extended lifespan. Despite these findings, it is still unknown if all pathways leading to extended lifespan converge at the process of autophagy or not. Here, an overview of modern developments related to the process of autophagy, its regulation and the molecular machinery involved is presented. In addition, this review focuses on one of the beneficial aspects of autophagy, its role in lifespan regulation.

• Journal of Astronomy and Space Sciences
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• 제30권3호
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• pp.133-140
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• 2013

Most of high energy cosmic rays (CRs) are thought to be produced by diffusive shock acceleration (DSA) at supernova remnants (SNRs) within the Galaxy. Fortunately, nonthermal emissions from CR protons and electrons can provide direct observational evidence for such a model and place strong constraints on the complex nonlinear plasma processes in DSA theory. In this study we calculate the energy spectra of CR protons and electrons in Type Ia SNRs, using time-dependent DSA simulations that incorporate phenomenological models for some wave-particle interactions. We demonstrate that the time-dependent evolution of the self-amplified magnetic fields, Alfv$\acute{e}$nic drift, and escape of the highest energy particles affect the energy spectra of accelerated protons and electrons, and so resulting nonthermal radiation spectrum. Especially, the spectral cutoffs in X-ray and ${\gamma}$-ray emission spectra are regulated by the evolution of the highest energy particles, which are injected at the early phase of SNRs. Thus detailed understandings of nonlinear wave-particle interactions and time-dependent DSA simulations of SNRs are crucial in testing the SNR hypothesis for the origin of Galactic cosmic rays.

• 제어로봇시스템학회논문지
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• 제10권12호
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• pp.1137-1147
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• 2004

In this paper, we proposed two types of adaptive control mechanism which is named HIA(Humoral Immune Algorithm) PID and CMIA(Cell-Mediated Immune Algorithm) controller based on biological immune system under engineering point of view. The HIA PID which has real time control scheme is focused on the humoral immunity and the latter which has the self-tuning mechanism is focused on the T-cell regulated immune response. To verify the performance of the proposed controller, some experiments for the control of AGV which is used for the port automation to carry container without human are performed. The experimental results for the control of steering and speed of an AGV system illustrate the effectiveness of the proposed control scheme. Moreover, in that results, proposed controllers have better performance than other conventional PID controller and intelligent control method which is the NN(neural network) PID controller.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.73-78
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• 1986

The effects of density and soil nutrient regime on competition between individuals in pure and mixed populations of two annuals. Chenopodium album and Digitaria sanguinalis were investigated at the level of enegy allocation. Seedling emergence of two species was extremely high (>90%) in both pure and mixed culture irrespective of the density and nutrient regime, but percentage of seedling establishment or fertile plant became gradually low with increasing density owing to 'self-thinning'. The mean plant dry weight was significantly reduced with increasing density and decreasing soil fertility. The dry matter production of D. sanguinalis in mixture was markedly greater than in pure culture under medium and high density. Also, as considered the number of seed production as reproductive allocation, relationship between them and the number of seed production per plant showed a similar tendency. Therefore, these results indicated that D. sanguinalis had a greater competitive advantage than C. album and energy allocations to variious organs were regulated by plastic response rather than determined genetically.

• 한국정보교육학회:학술대회논문집
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• 한국정보교육학회 2007년도 하계학술대회
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• pp.233-239
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• 2007

최근 정보통신기술의 발달로 학교 교육 현장에서는 미래형 교육을 위한 새로운 노력들이 시도되고 있다. u-러닝 (Ubiquitous Learning)으로 일컬어지는 이러한 교육을 이끌어가는 도구로서 UMPC (Ultra Mobile Personal Computer)는 기존 PC로 할 수 있는 모든 것을 가능케 하면서 나아가 휴대성과 이동성의 장점까지 겸비해 최근 급부상하고 있다. 본 연구에서는 이러한 동향을 반영하여 평생학습 사회에서 누적된 학습을 효과적으로 관리할 수 있도록 UMPC를 기반으로 한 학습 관리 시스템을 설계하였다. 본 시스템의 장점은 다음과 같다. 첫째, 자기조절학습 이론의 자기조절학습 전략을 적용함으로써 학습자가 능동적이고 자기주도적으로 학습을 점검하고 관리할 수 있도록 하였다. 둘째, 복잡하고 불필요한 기능을 배제하고 기존의 학습 자원과 도구를 최대한 활용하여 시스템의 편의성을 높임으로써 바쁜 일상에서도 간단하게 사용할 수 있는 학습 관리 및 생활 관리 도우미의 역할을 할 수 있도록 하였다. 셋째, 자기 학습에 대한 피드백을 지속적으로 할 수 있도록 도와줌으로써 궁극적으로 학업 성취 향상에 기여할 수 있도록 하였다.

• 대한공업교육학회지
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• 제30권1호
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• pp.120-132
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• 2005

The major purpose of this study was to provide a basic model of mobile guide system for visitor's individual learning, self-regulated learning in a museum. System model realized by this study was as follows; 1) This system distributed exhibit information to tourists in place of existing audio guides or curators. Using wireless communications, the PDA automatically delivered information about the exhibit. The artistic and visual displays maximized effective and quick transmission of information to the user. 2) It made visiting a museum fun, exciting and entertaining. With the PDA guide the museum visitor can interact with detailed descriptions of exhibits, videos and images. The museum visitor, can also play a quiz game, take photos, record voices and send e-mail.

• 천문학논총
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• 제34권3호
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• pp.67-79
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• 2019

We present a semi-analytical method to calculate the global evolution of the ionized state of the intergalactic medium, on the basis of physically motivated star formation histories in the early universe. This method incorporates not only the conventional scenarios in which the star formation rate is proportional to the growth rate of the halo collapse fraction, but also the more sophisticated scenarios in which the star formation is self-regulated. We show that this variance in the star-formation model strongly impacts the resulting reionization history, which bears a prospect for observational discrimination of these models. We discuss how observations of the anisotropic polarization of the cosmic microwave background and the global 21cm signal from the high-redshift universe, most notably by Planck and EDGES, may probe the history of reionization.