• 한국도서관정보학회지
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• 제49권4호
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• pp.21-51
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• 2018

출판 산업이 위기를 맞고 있는 가운데 그 활로로 도서관을 상정하였다. 그러나 도서관이 단순히 독서문화진흥의 촉매로서 출판 산업을 부흥시킬 수 없음을 전제하였다. 차라리 독자가 중심이 되고 도서관을 생산기지로 하는 독자들의 적극적인 생산과 수요를 출판이 수용함으로써 출판콘텐츠의 확대 재생산 체제를 출판 진흥의 모델로 제시하였다. 그 과정에 도서관/출판 협업 (협동조합) 형태의 독립출판 플랫폼을 설계하였고 그 유통과 재생산 모형을 제안하였다.

• Journal of Photoscience
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• 제9권2호
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• pp.287-289
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• 2002

Planarians show negative phototaxis and have extensive regenerative ability, including the ability to regenerate the brain. Recently the process of regeneration of the planarian brain has been divided into three steps based on the expression of neural markers. In this study, we have analyzed the process of recovery of the light response during head regeneration. Although morphological observations indicated that regeneration of the eyes and optic nerves appeared to be completed by the fourth day, the recovery of the evasion behavior against light was not recovered within 4 days after amputation. Functional recovery of the evasion behavior could be detected starting 5 days after amputation and then gradually recovered. We previously identified genes which are specifically expressed in the brain after the recovery of morphological structures. This characteristic suggested that these genes may be involved in functional recovery of the brain. To investigate the function of these genes, we performed gene knockout analysis using the RNA interference method. The results clearly indicated that these genes are involved in the functional recovery of the visual system.

• ETRI Journal
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• 제35권5호
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• pp.797-807
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• 2013

In this paper, an input receiver with a hysteresis characteristic that can work at voltage levels between 0.9 V and 5 V is proposed. The input receiver can be used as a wide voltage range Schmitt trigger also. At the same time, reliable circuit operation is ensured. According to the research findings, this is the first time a wide voltage range Schmitt trigger is being reported. The proposed circuit is compared with previously reported input receivers, and it is shown that the circuit has better noise immunity. The proposed input receiver ends the need for a separate Schmitt trigger and input buffer. The frequency of operation is also higher than that of the previously reported receiver. The circuit is simulated using HSPICE at 0.35-${\mu}m$ standard thin oxide technology. Monte Carlo analysis is conducted at different process conditions, showing that the proposed circuit works well for different process conditions at different voltage levels of operation. A noise impulse of ($V_{CC}/2$) magnitude is added to the input voltage to show that the receiver receives the correct logic level even in the presence of noise. Here, $V_{CC}$ is the fixed voltage supply of 3.3 V.

• 한국추진공학회지
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• 제19권6호
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• pp.64-71
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• 2015

스피닝 공정은 축대칭의 얇은 두께를 가지고 있는 속이 빈 실린더형 단면을 가지고 있는 부품에 일반적으로 사용된다. 전통적인 스피닝 제작 기술은 컨벤셔널 스피닝과 파워 스피닝(전단 스피닝과 유동성형)으로 구분된다. 액체추진로켓의 연소기의 재생냉각 챔버와 확대노즐부에서 적용된 스피닝에 대한 문헌조사를 수행하였다. 연소실과 노즐의 제작에 사용되는 스피닝은 대부분 맨드럴을 사용하였다. 최근에는 전통적인 냉간 스피닝에 비해 열간 스피닝도 많이 사용되고 있었다.

• BMB Reports
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• 제51권10호
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• pp.500-507
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• 2018

Cell reprogramming has been considered a powerful technique in the regenerative medicine field. In addition to diverse its strengths, cell reprogramming technology also has several drawbacks generated during the process of reprogramming. Telomere shortening caused by the cell reprogramming process impedes the efficiency of cell reprogramming. Transcription factors used for reprogramming alter genomic contents and result in genetic mutations. Additionally, defective mitochondria functioning such as excessive mitochondrial fission leads to the limitation of pluripotency and ultimately reduces the efficiency of reprogramming. These problems including genomic instability and impaired mitochondrial dynamics should be resolved to apply cell reprograming in clinical research and to address efficiency and safety concerns. Sirtuin (NAD+-dependent histone deacetylase) has been known to control the chromatin state of the telomere and influence mitochondria function in cells. Recently, several studies reported that Sirtuins could control for genomic instability in cell reprogramming. Here, we review recent findings regarding the role of Sirtuins in cell reprogramming. And we propose that the manipulation of Sirtuins may improve defects that result from the steps of cell reprogramming.

• 한국시뮬레이션학회논문지
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• 제12권3호
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• pp.31-40
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• 2003

This paper studies an optimal policy for a certain class of (s, S) inventory control systems, where the demands are characterized by the renewal arrival process. To minimize the average cost over a simulation period, we apply a stochastic optimization algorithm which uses the gradients of parameters, s and S. We obtain the gradients of objective function with respect to ordering amount S and reorder point s via a combined perturbation method. This method uses the infinitesimal perturbation analysis and the smoothed perturbation analysis alternatively according to occurrences of ordering event changes. The optimal estimates of s and S from our simulation results are quite accurate. We consider that this may be due to the estimated gradients of little noise from the regenerative system simulation, and their effect on search procedure when we apply the stochastic optimization algorithm. The directions for future study stemming from this research pertain to extension to the more general inventory system with regard to demand distribution, backlogging policy, lead time, and inter-arrival times of demands. Another direction involves the efficiency of stochastic optimization algorithm related to searching procedure for an improving point of (s, S).

• Animal cells and systems
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• 제14권2호
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• pp.73-81
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• 2010

In this study, monoclonal antibodies against lysosomal acid phosphatase (LAP) of a salamander, Hynobius leechii, were used to determine the spatial and temporal expression of the LAP in the regenerating limbs. The Western blot and immunohistochemical analysis in the limb regeneration revealed that LAP was highly expressed at the dedifferentiation stage, especially in the wound epidermis and dedifferentiating limb tissues such as muscle and cartilage. With RA treatment, the LAP expression became upregulated in terms of both level and duration in the wound epidermis, blastemal cell and dedifferentiating limb tissues. In addition, in situ activity staining of LAP showed a similar result to that of immunohistochemistry. Thus, the activity profile of LAP activity coincides well with the expression profile of LAP during the dedifferentiation period. Furthermore, to examine the effects of lysosomal enzymes including LAP on salamander limb regeneration, lysosome extract was microinjected into limb regenerates. Interestingly, when the lysosome extract was microinjected into limb regenerates with a low dose of RA($50\;{\mu}g/g$ body wt.), skeletal pattern duplication occurred frequently in the proximodistal and transverse axes. Therefore, lysosomal enzymes might cause the regenerative environment and RA plays dual roles in the modification of positional value as well as evocation of extensive dedifferentiation for pattern duplication. In conclusion, these results support the hypothesis that dedifferentiation is a crucial event in the process of limb regeneration and RA-evoked pattern duplication, and lysosomal enzymes may play important role(s) in this process.

• 한국수소및신에너지학회논문집
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• 제31권6호
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• pp.637-645
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• 2020

In this paper, entransy analysis is carried out for combined heat and power (CHP) generation system driven by low-grade heat source compared with energy and exergy analyses. The system consists of a regenerative organic rankine cycle (ORC) and an additional process heater in a series circuit. Special attention is paid to the effects of the turbine inlet pressure, source temperature, and the working fluid on the thermodynamic performance of the system. Results showed that the work efficiency of entransy is higher than that of energy but lower than that of exergy, wheress the process heat efficiency of entransy is lower than that of energy but higher than that of exergy. Entrance analysis showed the potential to complement the exergy analysis in the optimal design of the energy system.

• Journal of Ginseng Research
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• 제28권1호
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• pp.18-26
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• 2004

The effect of Panax ginseng administration in muscle inflammatory process induced after eccentric exercise, that causes myofibrillar disruption, was studied. Changes in lipid peroxidation, inflammation, glycogen levels in muscle and release of myocellular proteins to blood were measured. The analyses were performed immediately after eccentric exercise and over week since this period are necessary for the muscle damage-repair cycle. The ginseng extract (100 mg kg$^{-1}$ ) was orally administered to rats for three months, before the eccentric exercise performance. The results showed the protective role of ginseng against skeletal muscle damage. This effect could be associated with their membrane stabilising capacity since creatine kinase (CK) activity was significantly decreased 96 h post-exercise from 523$\pm$70 to 381$\pm$53 and 120 h post-exercise from 443$\pm$85 to 327$\pm$75 in treated animals. $\beta$-glucuronidase activity, as indicator of inflammation, showed a significant reduction of about 15-25% in soleus, vastus and triceps in these post-exercise times. The lipid peroxidation, measured by malondyaldehyde levels, was significantly decreased in the 24 h post-exercise period in soleus and vastus intermedius muscles and on the recovery period. Finally ginseng administration reduced significantly the decrease of the glycogen levels immediately after exercise and when the regenerative process took place (72-168 h post exercise). Collectively, the results have showed that ginseng did not inhibit the vital inflammatory response process associated with the muscle damage-repair cycle but presumably ameliorate the injury.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.271-275
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• 2010

연소기 재생냉각 챔버 노즐확장부의 외피구조물 제작을 위한 성형치구 설계에 대한 연구를 수행하였다. 연소기 챔버에서 두께가 얇은 외피구조물은 판재의 성형을 이용하여 제작한다. 노즐확장부 외피구조물의 성형에서 노즐확장부와 동일한 형상의 치구로 성형하면 성형 후 구조물의 형상이 노즐확장부와 일치하지 않고 탄성복원에 의하여 그 형상이 변화한다. 따라서 노즐확장부 형상과 동일한 형상으로 성형을 완성하기 위해서는 탄성복원을 고려한 성형치구의 설계가 필요하다. 본 연구에서는 초기 성형 후 탄성복원에 의한 노즐형상과 실제 구조물의 형상과의 오차를 없애기 위하여 오차를 보상한 새로운 성형치구용 형상을 생성하였다. 구조해석 결과 설계 수정된 성형치구로 성형하면 노즐 형상과 성형된 구조물과의 형상 오차가 매우 작게 감소함을 확인할 수 있었다.