• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.184-184
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• 2012

Recently, InGaN/GaN multi-quantum well grown on GaN pyramid structures have attracted much attention due to their hybrid characteristics of quantum well, quantum wire, and quantum dot. This gives us broad band emission which will be useful for phosphor-free white light emitting diode. On the other hand, by using quantum dot emission on top of the pyramid, site selective single photon source could be realized. However, these structures still have several limitations for the single photon source. For instance, the quantum efficiency of quantum dot emission should be improved further. As detection systems have limited numerical aperture, collection efficiency is also important issue. It has been known that micro-cavities can be utilized to modify the radiative decay rate and to control the radiation pattern of quantum dot. Researchers have also been interested in nano-cavities using localized surface plasmon. Although the plasmonic cavities have small quality factor due to high loss of metal, it could have small mode volume because plasmonic wavelength is much smaller than the wavelength in the dielectric cavities. In this work, we used localized surface plasmon to improve efficiency of InGaN qunatum dot as a single photon emitter. We could easily get the localized surface plasmon mode after deposit the metal thin film because lnGaN/GaN multi quantum well has the pyramidal geometry. With numerical simulation (i.e., Finite Difference Time Domain method), we observed highly enhanced decay rate and modified radiation pattern. To confirm these localized surface plasmon effect experimentally, we deposited metal thin films on InGaN/GaN pyramid structures using e-beam deposition. Then, photoluminescence and time-resolved photoluminescence were carried out to measure the improvement of radiative decay rate (Purcell factor). By carrying out cathodoluminescence (CL) experiments, spatial-resolved CL images could also be obtained. As we mentioned before, collection efficiency is also important issue to make an efficient single photon emitter. To confirm the radiation pattern of quantum dot, Fourier optics system was used to capture the angular property of emission. We believe that highly focused localized surface plasmon around site-selective InGaN quantum dot could be a feasible single photon emitter.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.634-637
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• 2012

In strawberry production, among others, the high incidence of diseases by pathogenic fungi resulting in the reduction of fruit yield and quality requires the development of eco-friendly management systems rather than chemical sprays to control them. The diameter of colonies grown in media at $25^{\circ}C$ for 5 days was measured to evaluate the in vitro inhibition of mycelial growth of 5 pathogenic fungi by irradiation with ultraviolet (UV-C, 264 nm). The mycelial growth of 5 pathogenic fungi was inhibited in potato dextrose agar (PDA) by the irradiation of UV-C for 1 hour a day, and was dramatically inhibited by the irradiation of UV-C for 9-12 h a day. The irradiation of UV-C for 9-12 h a day inhibited completely the growth of the late blight pathogen, Phytophthora cactorum. The irradiation distance of 40 to 50 cm was effective for the inhibition of mycelial growth of fungi. The mycelial growth of fungi without pre-incubation was inhibited strongly by UV-C irradiation compared to fungi pre-incubated for 2 days without light. The mycelia growth of Colletotrichum gloeosprioides and Fusarium oxysporum was inhibited strongly by UV-C irradiation in vegetable 8 juice agar compared to PDA.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.327-333
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• 2009

Biological Characteristic of Obolodiplosis robiniae and insecticidal activity of some insecticides against larvae of O. robiniae were investigated. Egg was in oval shape, and its color was light orange and became red when close to hatch. Length of the major axis and the minor axis of egg was 0.4 mm and 0.1 mm, respectively. Larval color was milky and size was 2.6 mm. Pupa was deep brown and its size was about 3.2 mm. Wing and abdomen of adult was black and reddish, respectively. Size of female adult was about 3.3 mm, and larger than male adult. Number of eggs in the ovary was $192.3{\pm}50.7$. First emergence was from late April to late May, and second from late May to late June. Third emergence was from late June to late July. Newly emerged adult escaped from soil, and second and third emerged adult escaped directly from gall of Robinia pseudoacacia leaf. Egg parasitoid was identified as Platygaster robiniae and parasite rate was 51.6%. Among test insecticides, imidacloprid 10% WP and thiacoprid 10% FL showed very strong insecticidal activity against larvae of O. robiniae at 48h later after treatment.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.478-485
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• 2011

Merocyanine derivatives transformed from spiropyran-containing compounds by irradiating the light of ultraviolet (UV) include zwitterion of phenolate anion and amine cation. Complexation of this phenolate anion on merocyaninemodified surface and Ni ion among metal ions led to a change of surface charge and it was measured with kelvin prove force microscopy (KFM). We found that the resultant surface potential decreased linearly as UV-exposed time increased, and finally were saturated. Also it was analyzed through XPS the immobilized amount of Ni ions was increased according to increase of UV-exposed time. It is considered that these properties could be applied for detection and a quantitative control of different metal ions. Further research is to aim construct specific scaffold/matrix which enable high selective, high sensitive and, especially, a quantitative immobilization of metal ions-binding biomaterials such as proteins and cells.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.52-61
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• 1986

Mycelial growth of Colletotrichun dematium and C. gloeosporioides isolated from anthracnose of Lycium chinense was favorable on V-8 Juice Agar media and Oatmeal Agar media of the four different media tested. Sporulation of C. dematium was favorable on PDA media and V-8 Juice Agar media and that of C. gloeosporioides was favorable on all media tested. The optimum temperature for mycelial growth of C. gloeosporioides and C. dematium was $25^{\circ}C$ and $28^{\circ}C$, respectively and sporulation of the fungi was stimulated under alternating NUV light and darkness. Of the seven nitrogen sources tested, gelatin was the most favorable for mycelial growth of C. gloeosporioides and glycin and gelatin were favorable for that of C. dematium. Of the eleven carbon sources tested, dextrin and sorbitol were favorable for mycelial growth of C. gloeosporioides and dextrin was the most favorable for that of C. dematium. Among the eleven fugicides tested, Benomyl, Folpet, Dithianon, Carbendazim and S-3308L were found superior for the inhibition of mycelial growth and spore germination of the fungi. They were, also, found superior for the control of anthracnose disease of L. chinense when they were applied to the plants in the field.

• Journal of Digital Convergence
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• v.10 no.3
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• pp.233-240
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• 2012

This study aimed to clarify any factors that may have effect on the appropriateness of hospital admission and hospitalization with the intention of facilitating more efficient occupancy of hospital beds and better medical services in the aspect of their quality, minimizing unnecessary occupancy of beds, and ultimately helping patients requiring acute treatments to use immediately hospitals. This paper selected 154 Stroke patients who left neurology department of one general hospital from March, 1, 2006 to September, 31, 2010 as targets to meet the rate according to medical care security and to see the trend of recent 4 years. As study method, this paper analized medical treatment record with AEP to evaluate the appropriateness of hospital admission and stay and the collected data was computerized through SPSS 12.0. Based upon the results above, the conclusion was drawn that the higher appropriateness of hospital admission and the shorter length of hospital stay will lead to the higher appropriateness of hospitalization. In other words, it is required to provide hospitalized patients with all kinds of behaviors including medical treatments and nursing care service, management of pharmaceuticals, tests, rehabilitation and symptoms, as well as instructions and information for patients. Meanwhile, as it was found that the length of hospital stay may affect the appropriateness of hospitalization, the longer length of hospital stay may result in reduced bed turnover rate. In this light, it is necessary to organize a task force team responsible for evaluation and control of the appropriateness of hospitalization and hospital stay length to improve the quality of medical service in a medical center, so that patients can leave the center timely. Ultimately, governmental supports such as expansion of long-term care facilities will reduce the necessary length of hospital stay so that patients with stroke can receive rehabilitative treatments and long-term care service shortly after completion of acute treatments.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.67-72
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• 2015

A study on thermal properties for a single-layer metal and a 2-ply metal (clad metals) was investigated for the application of heat sink. For the single-layer metal, a stainless steel (STS) and an aluminum (Al) were selected. Also, a roll bonded clad metal with STS and Al was chosen for the 2-ply metal. The thermal conductivity of the sample was obtained from the thermal diffusivity measured by the light flash analysis (LFA), specific heat and density. Measured thermal property values were compared with the calculated values using the data from the references. For the single-layer metal, measured values for the thermal diffusivity and thermal conductivity were smaller than calculated values. Differences between measured and calculated values were about 6% and 18% for the STS and Al samples, respectively. For the clad metals, however, a large difference (55%) was observed. Here, a relatively small thermal conductivity measured by LFA was due to the existence of a interface between STS and Al in the clad metal. Such a interface reduces the moving velocity of free electrons and phonons in the clad metal. For the development of a high performance heat-issipation module with the multi-layer structure, the control of interface properties which determine thermal properties was confirmed to be important.

• Journal of Life Science
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• v.23 no.6
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• pp.804-811
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• 2013

Melanopsin is an opsin-like photopigment found in the small proportion of photosensitive ganglion cells of the retina. It is involved in the regulation of the synchronization of the circadian cycle as well as in the control of pupillary light reflex. The purpose of the present study is to investigate whether melanopsin is also expressed in the other areas of the central visual system outside the retina. We have studied the distribution and morphology of neurons containing melanopsin in the mouse visual cortex with antibody immunocytochemistry. Melanopsin immunoreactivity was mostly present in neuronal soma, but not in nuclei. We found that melanopsin was present in a large subset of neurons within the adult mouse visual cortex with the highest density in layer II/III. In layer I of the visual cortex, melanopsin-immunoreactive (IR) neurons were rarely encountered. In the mouse visual cortex, the majority of the melanopsin-IR neurons consisted of round/oval cells, but was varied in morphology. Vertical fusiform and pyramidal cells were also rarely labeled with the anti-melanopsin antibody. The labeled cells did not show any distinctive distributional pattern. Some melanopsin-IR neurons in mouse visual cortex co-localized with nitricoxide synthase, calbindin and parvalbumin. Our data indicate that melanopsin is located in specific neurons and surprisingly widespread in visual cortex. This finding raises the need of the functional study of melanopsin in central visual areas outside the retina.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.515-520
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• 2016

This study conducted the research about the positive effects of Gynura Procumbens on preventing dermatitis and infectious diseases the contemporary people have. To do it, this study measured the concentration of NF-kB, the extract of Gynura Procumbens. In this regard, cytosol, the extract of Gynura Procumbens, and nucleus went through the separation process. The concentration of major NF-kB among various factors to control inflammation was measured with the use of HDF cell. Regarding RAW264.7 cell, the amounts of NO to play an important role in reacting the skin immune system as the media of neural transmission were analyzed. The outcome about the extracts of Gynura Procumbens injected show that it can be expected that as the NF-kB protein and mRNA band were reduced, Gynura Procumbens would have anti-inflammatory effects that could contribute to preventing dermatitis and diseases. In addition, the extracts of Gynura Procumbens have significantly reduced NO with their concentration increasing. In other words, Gynura Procumbens are considered to regulate dependently the production of NO in the concentration of extracts. Thus there is an expectation that the more intensive research would be conducted to heal dermatitis. And it is deemed that Gynura Procumbens would be used as materials for cosmetics as well as foods that the contemporary people can widely consume if a more careful research about anti-inflammatory effects would be sustained on a human bodies' clinical level.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.268-268
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• 2016

Chemical sensors have attracted much attention due to their various applications such as agriculture product, cosmetic and pharmaceutical components and clinical control. A conventional chemical and biological sensor is consists of fluorescent dye, optical light sources, and photodetector to quantify the extent of concentration. Such complicated system leads to rising cost and slow response time. Until now, the most contemporary thin film transistors (TFTs) are used in the field of flat panel display technology for switching device. Some papers have reported that an interesting alternative to flat panel display technology is chemical sensor technology. Recent advances in chemical detection study for using TFTs, benefits from overwhelming progress made in organic thin film transistors (OTFTs) electronic, have been studied alternative to current optical detection system. However numerous problems still remain especially the long-term stability and lack of reliability. On the other hand, the utilization of metal oxide transistor technology in chemical sensors is substantially promising owing to many advantages such as outstanding electrical performance, flexible device, and transparency. The top-gate structure transistor indicated long-term atmosphere stability and reliability because insulator layer is deposited on the top of semiconductor layer, as an effective mechanical and chemical protection. We report on the fabrication of InGaZnO TFTs with silver nanowire as the top gate electrode for the aim of chemical materials detection by monitoring change of electrical properties. We demonstrated that the improved sensitivity characteristics are related to the employment of a unique combination of nano materials. The silver nanowire top-gate InGaZnO TFTs used in this study features the following advantages: i) high sensitivity, ii) long-term stability in atmosphere and buffer solution iii) no necessary additional electrode and iv) simple fabrication process by spray.