• Progress in Medical Physics
• /
• v.15 no.3
• /
• pp.149-155
• /
• 2004

Purpose: To investigate the effects of tissue inhomogeneity corrections on the dose delivered to prostate cancer patients treated with Intensity-Modulated Radiation Therapy (IMRT). Methods and Materials: For five prostate cancer patients, IMRT treatment plans were generated using 6 MV or 10 MV X-rays. In each plan, seven equally spaced ports of photon beams were directed to the isocenter, neglecting the tissue heterogeneity in the body. The dose at the isocenter, mean dose, maximum dose, minimum dose and volume that received more than 95% of the isocenter dose in the planning target volume ( $V_{p>95%}$) were measured. The maximum doses to the rectum and the bladder, and the volumes that received more than 50, 75 and 90% of the prescribed dose were measured. Treatment plans were then recomputed using tissue inhomogeneity correction maintaining the intensity profiles and monitor units of each port. The prescription point dose and other dosimetric parameters were remeasured. Results: The inhomogeneity correction reduced the prescription point dose by an average 4.9 and 4.0% with 6 and 10 MV X-rays, respectively. The average reductions of the $V_{p>95%}$ were 0.8 and 0.9% with the 6 and 10 MV X-rays, respectively. The mean doses in the PTV were reduced by an average of 4.2 and 3.4% with the 6 and 10 MV X-rays, respectively. The irradiated volume parameters in the rectum and bladder were less decreased; less than 2.1 % (1.2%) of the reduction in the rectum (bladder). The average reductions in the mean dose were 1.0 and 0.5% in the rectum and bladder, respectively. Conclusions: Neglect of tissue inhomogeneity in the IMRT treatment of prostate cancer gives rise to a notable overestimation of the dose delivered to the target, whereas the impact of tissue inhomogeneity correction to the surrounding critical organs is less significant.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.32 no.4
• /
• pp.393-400
• /
• 2012

In recent years, nano-structured thin film systems are often applied in industries such as MEMS/NEMS device, optical coating, semiconductor or like this. Thin films are used for many and varied purpose to provide resistance to abrasion, erosion, corrosion, or high temperature oxidation and also to provide special magnetic or dielectric properties. Quite a number of articles to evaluate the characterization of thin film structure such as film density, film grain size, film elastic properties, and film/substrate interface condition were reported. Among them, the evaluation of film adhesive to substrate has been of great interest. In this study, we fabricated the polymeric thin film system with different adhesive conditions to evaluate the adhesive condition of the thin film. The nano-structured thin film system was fabricated by spin coating method. And then V(z) curve technique was applied to evaluate adhesive condition of the interface by measuring the surface acoustic wave(SAW) velocity by scanning acoustic microscope(SAM). Furthermore, a nano-scratch technique was applied to the systems to obtain correlations between the velocity of the SAW propagating within the system including the interface and the shear adhesive force. The results show a good correlation between the SAW velocities measured by acoustic spectroscope and the critical load measured by the nano-scratch test. Consequently, V(z) curve method showed potentials for characterizing the adhesive conditions at the interface by acoustic microscope.

• Journal of the Microelectronics and Packaging Society
• /
• v.13 no.3 s.40
• /
• pp.1-8
• /
• 2006

Higher density integration and adoption of new materials in advanced electronic package systems result in severe electrochemical reliability issues in microelectronic packaging due to higher electric field under high temperature and humidity conditions. Under these harsh conditions, metal interconnects respond to applied voltages by electrochemical ionization and conductive filament formation, which leads to short-circuit failure of the electronic package. In this work, in-situ water drop test and evaluation of corrosion characteristics for SnPb solder alloys in D.I. water and NaCl solutions were carried out to understand the fundamental electrochemical migration characteristics and to correlate each other. It was revealed that electrochemical migration behavior of SnPb solder alloys was closely related to the corrosion characteristics, and Pb was primarily ionized in both D.I. water and $Cl^{-}$ solutions. The quality of passive film formed at film surface seems to be critical not only for corrosion resistance but also for ECM resistance of solder alloys.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.1
• /
• pp.17-25
• /
• 2007

In most electronic imaging applications, image with high resolution(HR) are desired. HR means that pixel density within an image is high, and therefore HR image can offer more details that may be critical in various applications. Digital images that are captured by CCD and CMOS cameras usually have a very low resolution, which significantly limits the performance of image recognition systems. Image super-resolution techniques can be applied to overcome the limits of these imaging systems. Super-resolution techniques have been proposed to increase the resolution by combining information from multiple images. To techniques were consisted of the registration algorithm for estimation and shift, the nearest neighbor interpolation using weight of acquired frames and presented frames. In this paper, it is proposed the image interpolation techniques using the wavelet base function. This is applied to embody a correct edge image and natural image when expend part of the still image by applying the wavelet base function coefficient to the conventional Super-Resolution interpolation method. And the proposal algorithm in this paper is confirmed to improve the image applying the nearest neighbor interpolation algorithm, bilinear interpolation algorithm.,bicubic interpolation algorithm through the computer simulation.

• Biomedical Science Letters
• /
• v.13 no.4
• /
• pp.251-261
• /
• 2007

A myofiber of skeletal muscle is composed of myofibrils, sarcolemma (plasma membrane), and constameres, which anchor the myofibrils to the sarcolemma. Achvillin is a recently identified F-actin binding muscle protein, co-isolates with dystrophin and caveolin-3 in low-density sarcolemma of striated muscle, and colocalizes with dystrophin at costameres, the specialized adhesion sites in muscle. Archvillin also binds to nebulin and localizes at myofibrillar Z-discs, the lateral boundaries of the sarcomere in muscle. However other roles of archvillin on the dynamics of myofibrillogenesis remain to be defined. The goal of this study is, by using siRNA-mediated gene silencing technique, to investigate the effect of archvillin on the dynamics of myofibrillogenesis in cell culture of a mouse skeletal myogenic cell line (C2C12), where presumptive myoblasts withdraw from the cell cycle, fuse, undergo de novo myofibrillogenesis, and differentiate into mature myotubes. The roles of archvillin in the assembly and maintenance of myofibril and during the progression of myofibrillogenesis induced in skeletal myoblast following gene silencing in the cell culture were investigated. Fluorescence microscopy demonstrated that the distribution of archvillin was changed along the course of myofibril assembly with nebulin, vinculin and F-actin and then located at Z-lines with nebulin. Fluorescence microscopy demonstrated that knockdown of mouse archvillin expression led to an impaired assembly of new myofibrillar clusters and delayed fusion and myofibrillogenesis although the mouse archvillin siRNA did not affect those expressions of archvillin binding proteins, such as nebulin and F-actin. This result is corresponded with that of RT-PCR and western blots. When the perturbed archvillin was rescued by co-transfection with GFP or Red tagged human archvillin construct, the inhibited cell fusion and myotube formation was recovered. By using siRNA technique, archvillin was found to be involved in early stage of myofibrillogenesis. Therefore, the current data suggest the idea that archvillin plays critical roles on cell fusion and dynamic myofibril assembly.

• Korean Journal of Medicinal Crop Science
• /
• v.7 no.4
• /
• pp.308-313
• /
• 1999

Direct seeding is a cultivation method of Korean ginseng which can cut down production cost and increase productivity. This study was conducted to obtain detailed information about this method and to aid the development of it in Korea. Major pre-crops before ginseng cultivation were rice, corn and rye, and organic matters, such as rice straw, rye straw and poultry feces were used for basal fertilization. In direct seeding of the ginseng field, seeding density was 196 to 210 seeds per $3.3m^2$ and germination ratio was 67%. Survival ratio of 4-year-old ginsengs which were products of direct seeding was 51%, and more than 100 plants per $3.3m^2$ survived. The most critical diseases in the directly seeded ginseng field were grey mold, damping off, and stem diseases including stem spot disease. Plant growth of the ginseng cultivated by the direct seeding method was not different from the ginseng cultivated by transplanting method. But the root of the ginseng cultivated by the direct seeding method took the shape of a shorter main root compared to the ginseng cultivated by the transplanting method. Root yield per $3.3m^2$ of the direct seeding ginseng field was larger compared to the field of the transplanting cultivation.

• Journal of the Korean Society of Radiology
• /
• v.5 no.1
• /
• pp.11-18
• /
• 2011

The periosteum contains multipotent cells that can differentiate into osteoblasts and chondrocytes. Cultured periosteum-derived cells (PDCs) have an osteogenic capacity. The purpose of this study was to evaluate the interaction of PDCs with bone graft biomaterial. After cell isolation from the calvarial periosteum of Sprague-Dawley rats, cultured PDCs were placed in critical-sized calvarial defects with beta-tricalcium phosphate (${\beta}$-TCP). All rats were sacrificed 8 weeks after bone graft surgery, and the bone regenerative ability of bone grafting sides was evaluated by plain radiography, micro-computed tomography (CT), and histological examination. PDCs grafted with ${\beta}$-TCP displayed enhanced calcification in the defect site, density of regenerated bone and new bone formation within the defect and its boundaries. Furthermore, these PDCs more efficiently regenerated new bone as compared to grafted ${\beta}$-TCP only. The results suggest that cultured PDCs have the potential to promote osteogenesis in bone defects.

• Korean Journal of Food Science and Technology
• /
• v.20 no.3
• /
• pp.380-384
• /
• 1988

The coefficients of the hot-air and freeze dried garlic isotherms and the critical water activities of these were estimated to be 0.85-0.94 by the linear regression and 0.58-0.60 by the sensory evaluation and ${\Delta}E$ value. Water adsorption rate(K) of hot-air dried garlic packaged with $48{\mu}m$ low density polyethylene(LDPE) decreased from $0.12g\;H_2O/100g/day\;to\;0.093g\;H_2O$/100g/day with decreasing the package dimension from $0.051m^2\;to\;0.029m^2\;at\;40^{\circ}C$ and 75% RH, and that of freeze dried one decreased from $0.17g\;H_2O/100g/day\;to\;0.12g\;H_2O$/100g/day as the filling weight increased from 50g to 10g in the package of $0.051m^2$. Shelf-life of hot-air dried garlic packaged with $80{\mu}m$ LDPE were 99days at $40^{\circ}C,\;283day\;at\;30^{\circ}C\;and\;455\;days\;at\;15^{\circ}C$ in the 75% RH. The differences of water contents between predicted data with water vapor permeability of the conventional method and experimental data were 0-1.5% in the water content range of around 13-18%, but about 2 in the water content range of around 8-11%.

• World Technopolis Review
• /
• v.8 no.2
• /
• pp.74-81
• /
• 2019

Cities will soon host two third of the population worldwide, and already today 80% of the world energy is used in the 20 largest cities. Urban areas create 80% of the greenhouse gas emission, so we should take care that urban areas are smart and sustainable as implementations have especially here the greatest impact. Smart Cities (SC) or Smart Sustainable Cities (SSC) are the actual concepts that describe methodologies how cities can handle the high density of citizens, efficiency of energy use, better quality of life indicators, high attractiveness for foreign investments, high attractiveness for people from abroad and many other critical improvements in a shifting environment. But if we talk about Entrepreneurship Ecosystem and Innovation, we do not see a lot of literature covering this topic within those SC/SSC concepts. It seems that 'Smart' implies that all is embedded, or isn't it properly covered as brick stone of SC/SSC concepts, as they are handled in another 'responsibility silo', meaning that the policy implementation of a Science and Technology Park (STP) is handled in another governing body than SC/SSC developments. If this is true, we will obviously miss a lot of synergy effects and economies of scale effects. Effects that we could have in case we stop the siloed approaches of STPs by following a more holistic concept of a Smart Sustainable City, covering also a continuous flow of innovation into the city, without necessarily always depend on large corporate SSC solutions. We try to argue that every SSC should integrate SP/STP concepts or better their features and services into their methodology. The very limited interconnectivity between these concepts within the governance models limits opportunities and performance in both systems. Redesigning the architecture of the governance models and accepting that we have to design a system-of-systems would support the possible technology flow for smart city technologies, it could support testbed functionalities and the public-private partnership approach with embedded business models. The challenge is of course in complex governance and integration, as we often face siloed approaches. But real SSC are smart as they are connecting all those unconnected siloes of stakeholders and technologies that are not yet interoperable. We should not necessarily follow anymore old greenfield approaches neither in SSCs nor in SP and STP concepts from the '80s that don't fit anymore, being replaced by holistic sustainability concepts that we have to implement in any new or revised SSC concepts. There are new demands for each SP/STP being in or close to an SC/SCC as they have a continuous demand for feeding the technology base and the application layer and should also act as testbeds. In our understanding, a big part of STP inputs and outputs are still needed, but in a revised and extended format. We know that most of the SC/STP studies claim the impact is still far from understood and often debated, therefore we must transform the concepts where SC/STPs are not own 'cities', but where they act as technology source and testbed for industry and new SSC business models, being part of the SC/STP concept and governance from the beginning.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.1
• /
• pp.45-62
• /
• 2010

Zero plane displacement (d) is the elevated height of the apparent momentum sink exerted by the vegetation on the air. For a vegetative canopy, d depends on the roughness structure of a plant canopy such as leaf area index, canopy height and canopy density, and thus is critical for the analysis of canopy turbulence and the calculation of surface scalar fluxes. In this research note, we estimated d at the Gwangneung coniferous forest by employing two independent methods of Rotach (1994) and Martano (2000), which require only a single-level eddy-covariance measurement. In general, these two methods provided comparable estimates of $d/h_c$ (where $h_c$ is the canopy height, i.e., ~23m), which ranged from 0.51 to 0.97 depending on wind directions. These estimates of $d/h_c$ were within the ranges (i.e., 0.64~0.94) reported from other forests in the literature but were sensitive to the forms of the nondimensional functions for atmospheric stability. Our finding indicates that one should be careful in interepreation of zero plane displacement estimated from a single-level eddy covariance measurement that is conductaed within the roughness sublayer.