• Title/Summary/Keyword: Next generation ITS

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Emerging Frontiers of Graphene in Biomedicine

  • Byun, Jonghoe
    • Journal of Microbiology and Biotechnology
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    • 제25권2호
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    • pp.145-151
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    • 2015
  • Graphene is a next-generation biomaterial with increasing biomedical applicability. As a new class of one-atom-thick nanosheets, it is a true two-dimensional honeycomb network nanomaterial that attracts interest in various scientific fields and is rapidly becoming the most widely studied carbon-based material. Since its discovery in 2004, its unique optical, mechanical, electronic, thermal, and magnetic properties are the basis of exploration of the potential applicability of graphene. Graphene materials, such as graphene oxide and its reduced form, are studied extensively in the biotechnology arena owing to their multivalent functionalization and efficient surface loading with various biomolecules. This review provides a brief summary of the recent progress in graphene and graphene oxide biological research together with current findings to spark novel applications in biomedicine. Graphene-based applications are progressively developing; hence, the opportunities and challenges of this rapidly growing field are discussed together with the versatility of these multifaceted materials.

Advances in Crystalline Silicon Solar Cell Technology

  • Lee, Hae-Seok;Park, Hyomin;Kim, Donghwan;Kang, Yoonmook
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.82-82
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    • 2015
  • Industrial crystalline silicon (c-Si) solar cells with using a screen printing technology share the global market over 90% and they will continue to be the same for at least the next decade. It seems that the $2^{nd}$ generation and the $3^{rd}$ generation technologies have not yet demonstrated competitiveness in terms of performance and cost. In 2014, new world record efficiency 25.6% (Area-$143.7cm^2$, Voc-0.740V, $Jsc-41.8mA/cm^2$, FF-0.827) was announced from Panasonic and its cell structure is Back Contact $HIT^*$ c-Si solar cell. Here, amorphous silicon passivated contacts were newly applied to back contact solar cell. On the other hand, 24.9% $TOPCon^{**}$ cell was announced from Fraunhofer ISE and its key technology is an excellent passivation quality applying tunnel oxide (<2 nm) between metal and silicon or emitter and base. As a result, to realize high efficiency, high functional technologies are quite required to overcome a theoretical limitation of c-Si solar cell efficiency. In this presentation, Si solar cell technology summarized in the International Technology Roadmap for Photovoltaics ($^{***}ITRPV$ 2014) is introduced, and the present status of R&D associated with various c-Si solar cell technologies will be reviewed. In addition, national R&D projects of c-Si solar cells to be performed by Korea University are shown briefly.

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Clinical development of photodynamic agents and therapeutic applications

  • Baskaran, Rengarajan;Lee, Junghan;Yang, Su-Geun
    • 생체재료학회지
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    • 제22권4호
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    • pp.303-310
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    • 2018
  • Background: Photodynamic therapy (PDT) is photo-treatment of malignant or benign diseases using photosensitizing agents, light, and oxygen which generates cytotoxic reactive oxygens and induces tumour regressions. Several photodynamic treatments have been extensively studied and the photosensitizers (PS) are key to their biological efficacy, while laser and oxygen allow to appropriate and flexible delivery for treatment of diseases. Introduction: In presence of oxygen and the specific light triggering, PS is activated from its ground state into an excited singlet state, generates reactive oxygen species (ROS) and induces apoptosis of cancer tissues. Those PS can be divided by its specific efficiency of ROS generation, absorption wavelength and chemical structure. Main body: Up to dates, several PS were approved for clinical applications or under clinical trials. $Photofrin^{(R)}$ is the first clinically approved photosensitizer for the treatment of cancer. The second generation of PS, Porfimer sodium ($Photofrin^{(R)}$), Temoporfin ($Foscan^{(R)}$), Motexafin lutetium, Palladium bacteriopheophorbide, $Purlytin^{(R)}$, Verteporfin ($Visudyne{(R)}$), Talaporfin ($Laserphyrin^{(R)}$) are clinically approved or under-clinical trials. Now, third generation of PS, which can dramatically improve cancer-targeting efficiency by chemical modification, nano-delivery system or antibody conjugation, are extensively studied for clinical development. Conclusion: Here, we discuss up-to-date information on FDA-approved photodynamic agents, the clinical benefits of these agents. However, PDT is still dearth for the treatment of diseases in specifically deep tissue cancer. Next generation PS will be addressed in the future for PDT. We also provide clinical unmet need for the design of new photosensitizers.

디지털 자서전 연구를 위한 고려사항 - 디지털 기기에 익숙한 노년을 대상으로 (Considerations on Digital Autobiography of the Elderly in the Digital Age)

  • 주선이;김한일
    • 스마트미디어저널
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    • 제8권3호
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    • pp.80-87
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    • 2019
  • 노년세대는 발달과제인 '자아통합감'을 이루기 위해 기억, 평가, 종합의 역동적인 과정인 '인생회고'가 필요하다. 자서전 쓰기는 사고양상으로서 내러티브를 기반으로 인생회고의 도구 역할을 해왔다. 본 연구는 뉴실버세대에게 디지털 자서전이 자아통합감을 이루는 도구로서 본래의 역할을 충분히 할 수 있도록 고려해야 할 점을 모색하고자 한다. 이를 위해, 인생회고로 자아통합감을 이뤄가는 과정에 관한 이론들을 먼저 살펴보고, 자서전 쓰기의 양상 및 내러티브의 3가지 개념과 자서전적 글쓰기의 구성자질을 고찰할 것이다. 다음으로, 디지털 내러티브를 기반으로 한 디지털 자서전의 특징을 살펴보고, 뉴실버세대의 디지털 자서전 연구를 위한 고려 사항을 제안한다.

국내 수송환경에 적합한 마찰전기 나노발전기의 발전특성 분석 (Analysis of Power Generation Characteristics of TENG (Triboelectric Nanogenerator) Suitable for Domestic Transport Environment)

  • 박종민;정현모
    • 한국포장학회지
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    • 제28권3호
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    • pp.193-199
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    • 2022
  • Sustainable energy supplies without the recharging and replacement of charge storage device have become increasingly important. Among various energy harvesters, the triboelectric nanogenerator (TENG) has attracted considerable attention due to its high instantaneous output power, broad selection of available materials, eco-friendly and inexpensive fabrication process, and various working modes customized for target applications. The TENG harvests electrical energy from wasted mechanical energy in the ambient environment. TENG devices are very likely to be used in next-generation renewable energy and energy harvesting. TENG devices have the advantage of being able to manufacture very simple power devices. In this experiment, various organic dielectrics and inorganic dielectrics were used to improve the open voltage of TENG, Among the various organic dielectrics, Teflon-based FEP, which has the highest electron affinity, showed the highest open voltage and Al electrode was fabricated on Teflon substrate by sputtering deposition process. And AAO (Anodized Aluminum Oxide) nanostructures were applied to maximize the specific surface area of the TENG device. The power generation of TENG within the acceleration level (0.25, 0.5, 1.0, 1.5 and 2 G) and the frequency range (5-120 Hz) of the domestic transport environment was up to 4 V.

중국군의 해양작전능력과 한국군의 과제 (PRC Maritime Operational Capability and the Task for the ROK Military)

  • 김민석
    • Strategy21
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    • 통권33호
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    • pp.65-112
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    • 2014
  • Recent trends show that the PRC has stepped aside its "army-centered approach" and placed greater emphasis on its Navy and Air Force for a wider range of operations, thereby reducing its ground force and harnessing its economic power and military technology into naval development. A quantitative growth of the PLA Navy itself is no surprise as this is not a recent phenomenon. Now is the time to pay closer attention to the level of PRC naval force's performance and the extent of its warfighting capacity in the maritime domain. It is also worth asking what China can do with its widening naval power foundation. In short, it is time to delve into several possible scenarios I which the PRC poses a real threat. With this in mind, in Section Two the paper seeks to observe the construction progress of PRC's naval power and its future prospects up to the year 2020, and categorize time frame according to its major force improvement trends. By analyzing qualitative improvements made over time, such as the scale of investment and the number of ships compared to increase in displacement (tonnage), this paper attempts to identify salient features in the construction of naval power. Chapter Three sets out performance evaluation on each type of PRC naval ships as well as capabilities of the Navy, Air Force, the Second Artillery (i.e., strategic missile forces) and satellites that could support maritime warfare. Finall, the concluding chapter estimates the PRC's maritime warfighting capability as anticipated in respective conflict scenarios, and considers its impact on the Korean Peninsula and proposes the directions ROK should steer in response. First of all, since the 1980s the PRC navy has undergone transitions as the focus of its military strategic outlook shifted from ground warfare to maritime warfare, and within 30 years of its effort to construct naval power while greatly reducing the size of its ground forces, the PRC has succeeded in building its naval power next to the U.S.'s in the world in terms of number, with acquisition of an aircraft carrier, Chinese-version of the Aegis, submarines and so on. The PRC also enjoys great potentials to qualitatively develop its forces such as indigenous aircraft carriers, next-generation strategic submarines, next-generation destroyers and so forth, which is possible because the PRC has accumulated its independent production capabilities in the process of its 30-year-long efforts. Secondly, one could argue that ROK still has its chances of coping with the PRC in naval power since, despite its continuous efforts, many estimate that the PRC naval force is roughly ten or more years behind that of superpowers such as the U.S., on areas including radar detection capability, EW capability, C4I and data-link systems, doctrines on force employment as well as tactics, and such gap cannot be easily overcome. The most probable scenarios involving the PRC in sea areas surrounding the Korean Peninsula are: first, upon the outbreak of war in the peninsula, the PRC may pursue military intervention through sea, thereby undermining efforts of the ROK-U.S. combined operations; second, ROK-PRC or PRC-Japan conflicts over maritime jurisdiction or ownership over the Senkaku/Diaoyu islands could inflict damage to ROK territorial sovereignty or economic gains. The PRC would likely attempt to resolve the conflict employing blitzkrieg tactics before U.S. forces arrive on the scene, while at the same time delaying and denying access of the incoming U.S. forces. If this proves unattainable, the PRC could take a course of action adopting "long-term attrition warfare," thus weakening its enemy's sustainability. All in all, thiss paper makes three proposals on how the ROK should respond. First, modern warfare as well as the emergent future warfare demonstrates that the center stage of battle is no longer the domestic territory, but rather further away into the sea and space. In this respect, the ROKN should take advantage of the distinct feature of battle space on the peninsula, which is surrounded by the seas, and obtain capabilities to intercept more than 50 percent of the enemy's ballistic missiles, including those of North Korea. In tandem with this capacity, employment of a large scale of UAV/F Carrier for Kill Chain operations should enhance effectiveness. This is because conditions are more favorable to defend from sea, on matters concerning accuracy rates against enemy targets, minimized threat of friendly damage, and cost effectiveness. Second, to maintain readiness for a North Korean crisis where timely deployment of US forces is not possible, the ROKN ought to obtain capabilities to hold the enemy attack at bay while deterring PRC naval intervention. It is also argued that ROKN should strengthen its power so as to protect national interests in the seas surrounding the peninsula without support from the USN, should ROK-PRC or ROK-Japan conflict arise concerning maritime jurisprudence. Third, the ROK should fortify infrastructures for independent construction of naval power and expand its R&D efforts, and for this purpose, the ROK should make the most of the advantages stemming from the ROK-U.S. alliance inducing active support from the United States. The rationale behind this argument is that while it is strategically effective to rely on alliance or jump on the bandwagon, the ultimate goal is always to acquire an independent response capability as much as possible.

Effective Passivation of Black Phosphorus under Ambient Conditions

  • Yoon, Jongchan;Lee, Zonghoon
    • Applied Microscopy
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    • 제47권3호
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    • pp.176-186
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    • 2017
  • Two-dimensional (2D) materials have been studied widely owing to their outstanding properties since monolayer graphene was isolated in 2004. Especially, among 2D materials, phosphorene, a single atomic layer of black phosphorus (BP), has been highlighted for its electrical properties. This material can serve as a substitute for graphene, which has been revealed as a "semi-metal", in next-generation semiconductors. However, few-layer BP is prone to degradation under ambient conditions owing to its reactivity with oxygen and water, which results in the condensation of water droplets on the surface of the BP flakes. This causes charge transfer from the phosphorus atom to oxygen, resulting in the formation of phosphoric acid (oxide) and degrades the various properties of BP. Therefore, it is necessary to find passivation methods to prevent BP flakes from being degraded under ambient conditions. This review article deals with recent studies on passivation methods for BP and their performance against oxygen and water, effects on the electrical properties of BP, and the extent to how they protect BP.

디지털 VCR의 영상압축 기술 및 그의 화질 개선에 관한 연구 (Study on the Digital VCR System and Its Image Enhancement Techniques)

  • 이형호;백준기
    • 방송공학회논문지
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    • 제1권2호
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    • pp.142-151
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    • 1996
  • 디지털 비디오 카세트 레코더(DVCR)는 디지털 기록과 다양한 디지털 영상처리 기술과 같은 여러가지 측면에서 놀랄만한 성능에 힘입어 차세대 VCR로 대두되고 있다. 본 논문에서는 DVCR 시스템의 표준규격을 이해하고, 성능을 평가하고, 재생된 DVCR의 영상을 개선시키는 알고리듬을 제안하고자 한다. 보다 자세히 설명하자면, DVCR 영상을 개선하기 위하여 이산 코사인 변환, 양자화, 역 이산코사인 변환과 역양자화를 영상 시스템의 열화요인으로 모델링하고, 이러한 열화모델 때문에 발생하는 블럭 현상을 적응적으로 복원하는 고속 알고리듬을 제안한다.

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Current Status and Future Promise of the Human Microbiome

  • Kim, Bong-Soo;Jeon, Yoon-Seong;Chun, Jongsik
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제16권2호
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    • pp.71-79
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    • 2013
  • The human-associated microbiota is diverse, varies between individuals and body sites, and is important in human health. Microbes in human body play an essential role in immunity, health, and disease. The human microbiome has been studies using the advances of next-generation sequencing and its metagenomic applications. This has allowed investigation of the microbial composition in the human body, and identification of the functional genes expressed by this microbial community. The gut microbes have been found to be the most diverse and constitute the densest cell number in the human microbiota; thus, it has been studied more than other sites. Early results have indicated that the imbalances in gut microbiota are related to numerous disorders, such as inflammatory bowel disease, colorectal cancer, diabetes, and atopy. Clinical therapy involving modulating of the microbiota, such as fecal transplantation, has been applied, and its effects investigated in some diseases. Human microbiome studies form part of human genome projects, and understanding gleaned from studies increase the possibility of various applications including personalized medicine.

문자와 영상 사이 (The Letter and the Image)

  • 김남연;윤학로
    • 인문언어
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    • 제8집
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    • pp.59-78
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    • 2006
  • The paper brings to question how image as a medium is becoming a replacement for traditional letters in the modern culture. Reflection the importance of image in the context of modern society with the changes in the values of communication. The importance of letters in its traditional format as a book that signified not only the method of communication but also power for those who governed during the days of illiteracy in the past has changed, in the beginning with the development of printing and today with movies etc. that supply endless images instead of words as a means of communication. The images are the next generation in the method of communication and can be noted from the earliest civilizations such as Egypt where the method of communication was not words but drawings that depicted specific significations. The use of images for communication purposes in light of this fact suggests that images was being used before words in societies and its communicative values greater than that of words.

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