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A Study on the Components of Library Services for Applying Universal Design (유니버설디자인 적용을 위한 도서관 서비스 구성요소에 관한 연구)

  • Kim, Bo-Il
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.21 no.3
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    • pp.5-16
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    • 2010
  • Libraries should offer their services to all users including those who find difficult to access knowledge information without any obstacles or discrimination. Therefore, this study, aiming at providing library services to all users by applying 'Universal Design' to libraries, extracted and presented five components in library services: universal convenience, which allows all users to use libraries; safety of services, which offers safety in library use; user-orientedness, which offers user-oriented library services; user request, which allows library services reflecting the needs of users; and economic feasibility of the services, which provide efficient and economic library services. The proposed five components will play the foundational role in implementing universal design on libraries so that all users can use library services.

Biological Turf Restoration

  • Wilson, Carol W.;Kim, Hyung-Ki
    • Asian Journal of Turfgrass Science
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    • v.7 no.1
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    • pp.31-34
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    • 1993
  • There is a growing concern in the United Stares over the environmental and human health implications associated with heavy use of water, pesticides, and inorganic ferilizers in maintaining picture perfect golf courses. There is also a growing awareness that a beautiful course is not necessarily a healthy course. The following discussion reviews the interrelationship of turfgrass and the soil that supports it and provides basic information on currently available alternatives to turf management practices that feature intensive application of inorganic fertilizers. water and pesticides. Soil is a dynamic natural environment in which microorganisms play an important role. Soil contains a large mass of microorganisms which produce thousands of enzymes that can catalyze the transformation and degradation of many organic molecules. (In top soil under optimum conditions may contain 10 billion cells per gram of soil.). Turfgrass and the soil which supports it are interdependent. The natural organic cycle as applied to turf and soil begins with healthy vigorous grass plants storing up the sun's energy in green plant tissues as chemical energy. Animals obtain energy by eating plants and when plants and animals die, their wastes are returned to the soil and provide "food" for soil microorganisms. In the next step of the organic cycle soil microorganisms break down complex plant tissues into more basic forms and make the nutrients available to grass roots. Finally, growing plants extract the available nutrients from the soil. By free operation of this organic cycle, natural grasslands have some of the most fertile soils on earths.

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Melatonin inhibits nicotinic acetylcholine receptor functions in bovine chromaffin cells

  • Jo, Su-Hyun;Lee, Seung-Hyun;Kim, Kyong-Tai;Choi, Se-Young
    • International Journal of Oral Biology
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    • v.44 no.2
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    • pp.50-54
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    • 2019
  • Melatonin is a neurotransmitter that modulates various physiological phenomena including regulation and maintenance of the circadian rhythm. Nicotinic acetylcholine receptors (nAChRs) play an important role in oral functions including orofacial muscle contraction, salivary secretion, and tooth development. However, knowledge regarding physiological crosstalk between melatonin and nAChRs is limited. In the present study, the melatonin-mediated modulation of nAChR functions using bovine adrenal chromaffin cells, a representative model for the study of nAChRs, was investigated. Melatonin inhibited the nicotinic agonist dimethylphenylpiperazinium (DMPP) iodide-induced cytosolic free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) increase and norepinephrine secretion in a concentration-dependent manner. The inhibitory effect of melatonin on the DMPP-induced $[Ca^{2+}]_i$ increase was observed when the melatonin treatment was performed simultaneously with DMPP. The results indicate that melatonin inhibits nAChR functions in both peripheral and central nervous systems.

Mitochondria: multifaceted regulators of aging

  • Son, Jyung Mean;Lee, Changhan
    • BMB Reports
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    • v.52 no.1
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    • pp.13-23
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    • 2019
  • Aging is accompanied by a time-dependent progressive deterioration of multiple factors of the cellular system. The past several decades have witnessed major leaps in our understanding of the biological mechanisms of aging using dietary, genetic, pharmacological, and physical interventions. Metabolic processes, including nutrient sensing pathways and mitochondrial function, have emerged as prominent regulators of aging. Mitochondria have been considered to play a key role largely due to their production of reactive oxygen species (ROS), resulting in DNA damage that accumulates over time and ultimately causes cellular failure. This theory, known as the mitochondrial free radical theory of aging (MFRTA), was favored by the aging field, but increasing inconsistent evidence has led to criticism and rejection of this idea. However, MFRTA should not be hastily rejected in its entirety because we now understand that ROS is not simply an undesired toxic metabolic byproduct, but also an important signaling molecule that is vital to cellular fitness. Notably, mitochondrial function, a term traditionally referred to bioenergetics and apoptosis, has since expanded considerably. It encompasses numerous other key biological processes, including the following: (i) complex metabolic processes, (ii) intracellular and endocrine signaling/communication, and (iii) immunity/inflammation. Here, we will discuss shortcomings of previous concepts regarding mitochondria in aging and their emerging roles based on recent advances. We will also discuss how the mitochondrial genome integrates with major theories on the evolution of aging.

Reconstruction of a small defect of the lower vermilion adjacent to white roll using a modified O-Z flap

  • Kim, Hong Il;Kim, Ho Sung;Park, Jin Hyung;Yi, Hyung Suk;Kim, Yoon Soo;Kim, Hyo Young
    • Archives of Craniofacial Surgery
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    • v.22 no.3
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    • pp.164-167
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    • 2021
  • Reconstruction of lip defects is important because the lips play an important role in maintaining aesthetic facial balance, facial expressions, and speech. There are various methods of lip reconstruction such as primary repair, skin grafting, and utilization of local and free flaps. It is important to select a proper reconstruction method according to the size and location of lip defect. Failure to select an appropriate method may result in distortion, color mismatch, sensory loss, and aesthetic imbalance. Herein we present a case of successful aesthetic reconstruction of the lower vermilion. We removed a venous malformation, which was limited to the lower vermilion and adjacent to the white roll, and repaired the defect using the modified O-Z flap.

Mining Loot Box News : Analysis of Keyword Similarities Using Word2Vec (확률형 아이템 뉴스 마이닝 : Word2Vec 활용한 키워드 유사도 분석)

  • Kim, Taekyung;Son, Wonseok;Jeon, Seongmin
    • Journal of Information Technology Services
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    • v.20 no.2
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    • pp.77-90
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    • 2021
  • Online and mobile games represent digital entertainment. Not only the game grows fast, but also it has been noted for unique business models such as a subscription revenue model and free-to-play with partial payment. But, a recent revenue mechanism, called a loot-box system, has been criticized due to overspending, weak protection to teenagers, and more over gambling-like features. Policy makers and research communities have counted on expert opinions, review boards, and temporal survey studies to build countermeasures to minimize negative effects of online and mobile games. In this process, speed was not seriously considered. In this study, we attempt to use a big data source to find a way of observing a trend for policy makers and researchers. Specifically, we tried to apply the Word2Vec data mining algorithm to news repositories. From the findings, we acknowledged that the suggested design would be effective in lightening issues timely and precisely. This study contributes to digital entertainment service communities by providing a practical method to follow up trends; thus, helping practitioners have concrete grounds for balancing public concerns and business purposes.

Numerical study of the run-up of a solitary wave after propagation over a saw-tooth-shaped submerged breakwater

  • Sun, Jiawen;Ma, Zhe;Wang, Dongxu;Dong, Sheng;Zhou, Ting
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.283-296
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    • 2020
  • A numerical model is established to investigate the run-up of a solitary wave after propagating over a triangular saw-tooth-shaped submerged breakwater. A rectangular-shaped submerged breakwater is simulated for comparison. Several factors, including the submerged depth, the lagoon length and the beach slope, are selected as independent variables. The free surface motions and velocity fields of the solitary wave interacting with the submerged breakwater are discussed. The results show that the submerged depth and lagoon length play significant roles in reducing the run-up. The influence of the beach slope is not significant. At the same submerged depth, the triangular saw-tooth-shaped submerged breakwater has only a slightly better effect than the rectangular-shaped submerged breakwater on the run-up reduction. However, a calmer reflected wave profile could be obtained with the rougher surface of the saw-tooth-shaped submerged breakwater. The study conclusions are expected to be useful for the conceptual design of saw-tooth-shaped submerged breakwaters.

Survey of Acoustic Frequency Use for Underwater Acoustic Cognitive Technology

  • Cho, A-ra;Choi, Youngchol;Yun, Changho
    • Journal of Ocean Engineering and Technology
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    • v.36 no.1
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    • pp.61-81
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    • 2022
  • The available underwater acoustic spectrum is limited. Therefore, it is imperative to avoid frequency interference from overlapping frequencies of underwater acoustic equipment (UAE) for the co-existence of the UAE. Cognitive technology that senses idle spectrum and actively avoids frequency interference is an efficient method to facilitate the collision-free operation of multiple UAE with overlapping frequencies. Cognitive technology is adopted to identify the frequency usage of UAE to apply cognitive technology. To this end, we investigated two principle underwater acoustic sources: UAE and marine animals. The UAE is classified into five types: underwater acoustic modem, acoustic positioning system, multi-beam echo-sounder, side-scan sonar, and sub-bottom profiler. We analyzed the parameters of the frequency band, directivity, range, and depth, which play a critical role in the design of underwater acoustic cognitive technology. Moreover, the frequency band of several marine species was also examined. The mid-frequency band from 10 - 40 kHz was found to be the busiest. Lastly, this study provides useful insights into the design of underwater acoustic cognitive technologies, where it is essential to avoid interference among the UAE in this mid-frequency band.

A hybrid conventional computer simulation via GDQEM and Newmark-beta techniques for dynamic modeling of a rotating micro nth-order system

  • Fan, Linyuan;Zhang, Xu;Zhao, Xiaoyang
    • Advances in nano research
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    • v.12 no.2
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    • pp.167-183
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    • 2022
  • In this paper, the free and forced vibration analysis of rotating cantilever nanoscale cylindrical beams and tubes is investigated under the external dynamic load to examine the nonlocal effect. A couple of nonlocal strain gradient theories with different beams and tubes theories, involving the Euler-Bernoulli, Timoshenko, Reddy beam theory along with the higher-order tube theory, are assumed to the mathematic model of governing equations employing the Hamilton principle in order to derive the nonlocal governing equations related to the local and accurate nonlocal boundary conditions. The two-dimensional functional graded material (2D-FGM), made by the axially functionally graded (AFG) in conjunction with the porosity distribution in the radial direction, is considered material modeling. Finally, the derived Partial Differential Equations (PDE) are solved via a couple of the generalized differential quadrature element methods (GDQEM) with the Newmark-beta techniques for the time-dependent results. It is indicated that the boundary conditions equations play a crucial task in responding to nonlocal effects for the cantilever structures.

Integrity, Orbit Determination and Time Synchronisation Algorithms for Galileo

  • Merino, M.M. Romay;Medel, C. Hernandez;Piedelobo, J.R. Martin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.9-14
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    • 2006
  • Galileo is the European Global Navigation Satellite System, under civilian control, and consists on a constellation of medium Earth orbit satellites and its associated ground infrastructure. Galileo will provide to their users highly accurate global positioning services and their associated integrity information. The elements in charge of the computation of Galileo navigation and integrity information are the OSPF (Orbit Synchronization Processing Facility) and IPF (Integrity Processing Facility), within the Galileo Ground Mission Segment (GMS). Navigation algorithms play a key role in the provision of the Galileo Mission, since they are responsible for computing the essential information the users need to calculate their position: the satellite ephemeris and clock offsets. Such information is generated in the Galileo Ground Mission Segment and broadcast by the satellites within the navigation signal, together with the expected a-priori accuracy (SISA: Signal-In-Space Accuracy), which is the parameter that in fault-free conditions makes the overbounding the predicted ephemeris and clock model errors for the Worst User Location. In parallel, the integrity algorithms of the GMS are responsible of providing a real-time monitoring of the satellite status with timely alarm messages in case of failures. The accuracy of the integrity monitoring system is characterized by the SISMA (Signal In Space Monitoring Accuracy), which is also broadcast to the users through the integrity message.

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