• Applied Microscopy
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• v.28 no.4
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• pp.539-549
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• 1998

The silk glands of the spiders are of several types. Among the several types of spider's silk glands, the principal fibers used in constructing the eggcase are products of the tubuliform glands (TBG), which are present only in females. Development of these glands parallels maturations of the ovaries and fat bodies. In order to understand the mechanism of eggcase-silk production, this paper has examined the fine structural changes of the TBG during the period of egg maturation in the garden spider, Argiope aurentia. Between the two kinds of secretory granules observed in the glandular epithelium of the mature TBG, the electron-dense granules which have paracrystalline structure are revealed to be the precursors of the eggcase silk fibers. During the production of eggcase, rapid release of the secretory product occurs at apical surface by the mechanism of apocrine secretion. Moreover, secondary lysosomes appear due to the rapid disorganization of cellular components during the eggcase formation. Examinations of formed fibers indicate a multicomponent internal structure, and electron micrographs reveal each fiber contains numerous electron lucent fibrils embedded in an amorphous electron dense matrix. The secretory precursors are produced as separated vesicles via well-oriented rER, and no Golgi complex has been found in the glandular epithelial cells.

• Korean Journal of Materials Research
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• v.27 no.6
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• pp.307-311
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• 2017

Organometal halide perovskite materials, due to the tunability of their electronic and optical properties by control of composition and structure, have taken a position of significant importance in optoelectronic applications such as photovoltaic and lighting devices. Despite numerous studies on the structure - property relationship, however, practical application of these materials in electronic and optical devices is still limited by their processability during fabrication. Achieving nano-sized perovskite particles embedded in a polymer matrix with high loading density and outstanding photoluminescence performance is challenging. Here, we demonstrate that the careful control of nanoparticle formation and growth in the presence of poly(methyl methacrylate) results in perovskite nanoparticle - polymer nanocomposites with very good dispersion and photoluminescence. Furthermore, this approach is found to prevent further growth of perovskite nanoparticles, and thus results in a more uniform film, which enables fabrication using the perovskite nanoparticles.

• Journal of Internet Computing and Services
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• v.7 no.2
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• pp.121-136
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• 2006

Software architecture and protocols to be maintained between components for the reconfigurable SDR system is analyzed and suggest system design idea for the implementation of software. To do this, related surveys are reviews and set up the system model with the structure of embedded system. SDR system architecture is suggested with five layered structure, consisted with hardware, operating system, middle-ware, service objects and application layer. SDR system is designed to be work on the basis of Linux operating system, and aimed to be scalable and reconfigurable. It is introduced the design result of software protocol and state transition diagram for the implementations of software download function which is the most important feature in SDR.

• Journal of the Korean Society for Library and Information Science
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• v.37 no.2
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• pp.153-168
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• 2003

A hyperlink on academic World Wide Web has started to be recognized as a form of collaborative communication network connecting individual researchers and research groups and expanding their collaboration relations by making possible easy and direct online contact among people or groups anywhere in the world. This paper describes the structure of academic hyperlinks embedded in universities' Web sites hosted at the 10 Asian countries and further, examines the association between the structure of the hyperlink network and collaborative communication pattern among those countries based on their frequency of co-authoring articles. This research found that the number of inter-hyperlinks among universities' Web sites was significantly correlated with the frequency of co-authored articles across the 10 countries.

• Earthquakes and Structures
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• v.3 no.3_4
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• pp.203-230
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• 2012

This paper presents results for impedance (and compliance) functions and input motions of foundations in a layered half-space computed on the basis of a procedure that combines a consistent transmitting boundary with continued-fraction absorbing boundary conditions which are accurate and effective in modeling wave propagation in various unbounded domains. The effects of obliquely incident seismic waves in a layered half-space are taken into account in the formulation of the transmitting boundary. Using the numerical model, impedance (and compliance) functions and input motions of rigid circular foundations on the surface of or embedded in a homogeneous half-space are computed and compared with available published results for verification of the procedure. Extrapolation methods are proposed to improve the performance in the very-low-frequency range and for the static condition. It is concluded from the applications that accurate analysis of foundation dynamics and soil-structure interaction in a layered half-space can be carried out using the enhanced consistent transmitting boundary and the proposed extrapolations.

• Animal cells and systems
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• v.7 no.1
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• pp.35-41
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• 2003

The principal fibers used in constructing the cocoon in the garden spider, Argiope aurantia, are large-diameter fibers developed from tubuliform glands and small-diameter fibers presumed to be spun by the aciniform silk glands. Scanning electron micrographs of the large-diameter fibers on both surfaces of the cocoon clearly reveal their fine structural differences. While the silk fibers on the inner surface have smooth and homogeneous appearances, each fiber on the outer surface represents a multicomponent internal structure. Examination of each fibers using transmission electron microscope also provides additional evidence that the multicomponent fibers contain numerous electron lucent fibrils embedded in an amorphous electron dense matrix. It has been also revealed that two types of secretory granules presumed to be the precursors of tubuliform fibers are closely related to the production of distinct coloration in luminal contents - brownish and yellowish components. Moreover, these electron-dense granules, possibly precursor of fibrillar component, and electron-lucent granules, possibly precursor of matrix component, are densely packed and remain close to each other without fusion. It is critical evidence that the individual tubuliform fiber is not only heterogeneous and multicomponent but also takes place in a variety at manners throughout the length of the gland.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.810-818
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• 2020

A moored floating structure may exhibit resonant motion responses to low-frequency excitations. Similar to the resonant responses of many vibration systems, the motion amplitude of a moored floating structure is significantly affected by the damping of the entire system. In such cases, the damping contributed by the mooring lines sometimes accounts for as much as 80% of the total damping. While the damping induced by catenary mooring lines is well-investigated, few studies have been conducted on the damping induced by taut mooring lines, especially one partly embedded in soil. The present study develops a simple but accurate model for estimating the damping contributed by mooring lines. A typical type of taut mooring line was used as the reference and the hydrodynamic drag force and soil resistance were taken into consideration. The proposed model was validated by comparing its predictions with those of a previously developed model and experimental measurements obtained by a physical model. Case studies and sensitivity studies were also conducted using the validated model. The damping induced by the soil resistance was found to be considerably smaller than the hydrodynamic damping. The superposition of the wave frequency motion on the low-frequency motion was also observed to significantly amplify the damping induced by the mooring lines.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.11
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• pp.4122-4144
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• 2021

In this fast-paced technological world, the Internet of Things is a ground breaking technology which finds an immense role in the present electronic world which includes different embedded sensors, devices and most other things which are connected to the Internet. The IoT devices are designed in a way that it helps to collect various forms of data from varied sources and transmit them in digitalized form. In modern era of IoT technology data security is a trending issue which greatly affects the confidentiality of important information. Keeping the issue in mind a novel light encryption strategy known as LCB is designed for IoT devices for optimal security. LCB exploits the benefits of Feistel structure and the architectural benefits of substitution permutation network both to give more security. Moreover, this newly designed technique is tested on (Virtex-7) XC7VX330T FPGA board and it takes much little area of 224 GE (Gate Equivalent) and is extremely fast with very less combinational path delay of 0.877 ns. An in-depth screening confirms the proposed work to promise more security to counter cryptographic attacks. Lastly the Avalanche Effect (AE) of LCB showed as 63.125% and 63.875% when key and plaintext (PT) are taken into consideration respectively.

• Geomechanics and Engineering
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• v.29 no.1
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• pp.53-63
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• 2022

Simplified analytical solutions are developed for the dynamic analyses of an axially loaded pile foundation embedded in a transverse-isotropic, fluid-filled, poro-visco-elastic soil with rigid substratum. The pile is modeled as a viscoelastic Rayleigh-Love rod, while the surrounding soil is regarded as a transversely isotropic, liquid-saturated, viscoelastic, porous medium of which the mechanical behavior is represented by the Boer's poroelastic media model and the fractional derivative model. Upon the separation of variables, the frequency-domain responses for the impedance function of the pile top, and the vertical displacement and the axial force along the pile shaft are gained. Then by virtue of the convolution theorem and the inverse Fourier transform, the time-domain velocity response of the pile head is derived. The presented solutions are validated, compared to the existing solution, the finite element model (FEM) results, and the field test data. Parametric analyses are made to show the effect of the soil anisotropy and the excitation frequency on the pile-soil dynamic responses.

• Journal of Advanced Navigation Technology
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• v.27 no.1
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• pp.1-7
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• 2023

Mission autonomy system should be embedded on UAV (Unmanned Aerial Vehicle) for mosaic warfare where UAVs autonomously assign tasks to themselves. UxAS (Unmanned x-systems Autonomy Service) proposed by Air Force Research Laboratory is mission autonomy system for unmanned platforms. UxAS has extensible structure composed of numerous module services. However, UxAS can conduct mission autonomy process only when an operator sends an autonomy request. In this paper, We analyze the process of mission autonomy in UxAS, and propose an improved structure of UxAS where mission autonomy process is autonomously triggered by situation awareness service without the request of the operator. The proposed process was validated by simulation.