• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.296-296
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• 2014

We investigate experimentally and theoretically the splitting of surface plasmon (SP) resonance peaks under TE- and TM-polarized illumination. The SP structure at infrared wavelength is fabricated with a 2-dimensional square periodic array of circular holes penetrating through Au (gold) film. In brief, the processing steps to fabricate the SP structure are as follows. (i) A standard optical lithography was performed to produce to a periodic array of photoresist (PR) circular cylinders. (ii) After the PR pattern, e-beam evaporation was used to deposit a 50-nm thick layer of Au. (iii) A lift-off processing with acetone to remove the PR layer, leading to final structure (pitch, $p=2.2{\mu}m$; aperture size, $d=1.1{\mu}m$) as shown in Fig. 1(a). The transmission is measured using a Nicolet Fourier-transform infrared spectroscopy (FTIR) at the incident angle from $0^{\circ}$ to $36^{\circ}$ with a step of $4^{\circ}$ both in TE and TM polarization. Measured first and second order SP resonances at interface between Au and GaAs exhibit the splitting into two branches under TM-polarized light as shown in Fig. 1(b). However, as the incidence angle under TE polarization is increased, the $1^{st}$ order SP resonance peak blue-shifts slightly while the splitting of $2^{nd}$ order SP resonance peak tends to be larger (not shown here). For the purpose of understanding our experimental results qualitatively, SP resonance peak wavelengths can be calculated from momentum matching condition (black circle depicted in Fig. 2(b)), $k_{sp}=k_{\parallel}{\pm}iG_x{\pm}jG_y$, where $k_{sp}$ is the SP wavevector, $k_{\parallel}$ is the in-plane component of incident light wavevector, i and j are SP coupling order, and G is the grating momentum wavevector. Moreover, for better understanding we performed 3D full field electromagnetic simulations of SP structure using a finite integration technique (CST Microwave Studio). Fig. 1(b) shows an excellent agreement between the experimental, calculated and CST-simulated splitting of SP resonance peaks with various incidence angles under TM-polarized illumination (TE results are not shown here). The simulated z-component electric field (Ez) distribution at incident angle, $4^{\circ}$ and $16^{\circ}$ under TM polarization and at the corresponding SP resonance wavelength is shown in Fig. 1(c). The analysis and comparison of theoretical results with experiment indicates a good agreement of the splitting behavior of the surface plasmon resonance modes at oblique incidence both in TE and TM polarization.

• Korean Journal of Veterinary Research
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• v.35 no.1
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• pp.149-158
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• 1995

The purpose of the present study was to understand the pathogenesis of infections in piglets inoculated with C parvum isolated from mice alone and combined with porcine rotavirus (S-80). Thirteen 10-day piglets were divided in four groups; Three, A group, were only given by C parvum. Four, B group, were orally administrated with firstly porcine rotavirus and then C patvum. Three, C group, were orally inoculated with porcine rotavirus alone. The rest, D group, were used as controls. During the experiment, there were daily recorded clinical signs including diarrhea to each pig. According to the periodic intervals for necropsy, all pigs were sacrificed from 4 to 12 days after the final inoculation of C parvum. Location and distribution of two pathogens, C parvum and rotavirus, in the intestinal mucosa of piglets tested were examined by pathological and immunohistological means. In addition, parasitological test using the feces of piglets was applied for the detection of cryptosporidial oocysts as well. A group showed diarrhea from 4 to 6 days post-inoculation(PI) and also discharged C parvum oocysts in feces during the day 4 to 7 PI. In tissue sections of jejunum and ileum, cryptosporidial oocysts were observed a few on the top of villi with slightly fusion. B group represented sign of diarrhea and discharge of oocysts from 2 to 11 days PI. There were some cryptosporidial oocysts both in the jejunal lumen and in the lumen of mucosal glands. As progressed, oocysts were most commonly distributed on the tip of villi of jejunum. Histopathologically there were also mild to moderately fused, attenuated focal desquamated, congested villi and mononuclear cell infiltration of varying degrees in the lamina propria of small intestine and colon at the day 4 and 7 PI. C group showed slightly to mildly attenuated and fused top of villi and mildly mucosal congestion. D group as controls was grossly and histopathologically normal in all parts of intestine. The present results indicate that the piglets inoculated with C parvum only are certainly milder in pathogenesis including duration of clinical course and severity of lesion than those in piglets concurrently infected with porcine rotavirus and C parvum. Also the strain (VRI-CN91) of C parvum used in the study has very low pathogenicity to occur enteritis of piglets.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.41.2-41.2
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• 2018

EL CVn-type eclipsing binaries are composed of a massive A-type main-sequence primary star and a hotter B-type secondary one. These are worthy of particular attention because the secondary stars are rare objects to be extremely low-mass white dwarf precursors (ELM proto-WD) with the mass of ${\leq}0.2M_{\odot}$, evolving to higher effective temperatures and higher surface gravities. A few of them were discovered to show multi-periodic pulsations in one or both components. We monitored one of these rare and interesting objects, J0247-25 (=1SWASP J024743.37-251549.2), at two KMTNet sites of SAAO in South Africa and SSO in Australia. The observations were performed with the KMTNet 1.6m telescopes and pre-science 4K CCD cameras during the system test run from July to November 2014. Using the photometric data obtained for a total of 23 nights, we constructed well-defined eclipsing light curves in B/V-bands and derived absolute parameters (mass and radius, etc.) of each binary component. After subtracting model eclipsing curves from the data, we detected seven frequencies with 33~53 cycles per day (c/d) and identified them to be Delta Sct-type pulsations originated from the A-type primary component. Five frequencies were turned out to be excited by rotational splitting of non-radial pressure modes, enabled us to investigate rotational properties. We could not detect any frequency higher than 100 c/d, implying that pulsation amplitudes of the proto-WD secondary decrease greatly.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.137-153
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• 2004

We have analyzed the ingredients of 17 pieces of Bronze Age bronze ware, and an additional 22 pieces of Koryo and Chosun dynasty bronze ware. We have also conducted analysis of the extraction sites where these bronze ware items were found. For analyzing the main ingredient the bronze ware items have been divided into 3 groups - Cu-Sn(70?75:20), Cu-Pb-Sn(70:10:10), Cu-Pb-Sn(60:10:20) type respectively. In tile cases of the Cu-Pb-Sn groups the division comes down to differences in the Cu content as the main component, and elements such as Ni, Fe, Co contribute as a micro ingredient. The geographical and periodic characteristics of ancient bronze ware items show that theircompositional element changes from Cu:Sn to Cu:Pb:Sn and the Cu content decreases with the period,while the Pb content increases with the period. Bronze ware items from Suchon Ri, Gongju (that were used in 3 B.C.) form very different categories from 3rd ${\~}$ 2nd B.C.. They additionally formed very different categories from those bronze ware items analyzed in this research. These bronze ware itemsare shown to be geographically close and periodically overlapped, but made of a new elemental composition. This shows an inflow of a production technical culture present in the new bronze wares. The main component content of Cu is lower, and the Co and Fe contents (as microelements) are much higher than that of other bronze ware items. Such facts showthat those bronze ware items used completely different materials from bronze ware items in other cultural areas, or that there were differences in smelting techniques In the places where ancient bronze ware items have been extracted, it is presumed that the materials originated from the southern parts of Korea andnorthern parts and southern parts of China. .As more bronze ware scientific research is compiled one can conclude that that there will be enough scientific evidence to study the Bronze Age culture of Koreasystematically.

• Journal of applied mathematics & informatics
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• v.39 no.3_4
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• pp.381-403
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• 2021

Consider the three-dimensional system of difference equations $x_{n+1}=\frac{{\prod_{j=0}^{k}}z_n-3j}{{\prod_{j=1}^{k}}x_n-(3j-1)\;\(a_n+b_n{\prod_{j=0}^{k}}z_n-3j\)}$, $y_{n+1}=\frac{{\prod_{j=0}^{k}}x_n-3j}{{\prod_{j=1}^{k}}y_n-(3j-1)\;\(c_n+d_n{\prod_{j=0}^{k}}x_n-3j\)}$, $z_{n+1}=\frac{{\prod_{j=0}^{k}}y_n-3j}{{\prod_{j=1}^{k}}z_n-(3j-1)\;\(e_n+f_n{\prod_{j=0}^{k}}y_n-3j\)}$, n ∈ ℕ₀, where k ∈ ℕ₀, the sequences $(a_n)_{n{\in}{\mathbb{N}}_0$, $(b_n)_{n{\in}{\mathbb{N}}_0$, $(c_n)_{n{\in}{\mathbb{N}}_0$, $(d_n)_{n{\in}{\mathbb{N}}_0$, $(e_n)_{n{\in}{\mathbb{N}}_0$, $(f_n)_{n{\in}{\mathbb{N}}_0$ and the initial values x_-3k, x_-3k+1, …, x₀, y_-3k, y_-3k+1, …, y₀, z_-3k, z_-3k+1, …, z₀ are real numbers. In this work, we give explicit formulas for the well defined solutions of the above system. Also, the forbidden set of solution of the system is found. For the constant case, a result on the existence of periodic solutions is provided and the asymptotic behavior of the solutions is investigated in detail.

• Journal of the Korean Ceramic Society
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• v.35 no.8
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• pp.813-818
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• 1998

A simple method to measure the elastic modulus E and Poisson's ratio v of diamod-like carbon (DLC) films deposited on Si wafer was suggested. Using the anisotropic etching technique of Si we could make the edge of DLC overhang free from constraint of Si substrate. DLC film is chemically so inert that we could not on-serve any surface damage after the etching process. The edge of DLC overhang free from constraint of Si substrate exhibited periodic sinusoidal shape. By measuring the amplitude and the wavelength of the sinu-soidal edge we could determine the stain of the film required to adhere to the substrate. Since the residual stress of film can be determine independently by measurement of the curvature of film-substrate com-posite we could calculated the biaxial elastic modulus E/(1-v) using stress-strain relation of thin films. By comparing the biaxial elastic modulus with the plane-strain modulus E/(1-{{{{ { v}^{2 } }}) measured by nano-in-dentation we could further determine the elastic modulus and Poisson's ratio independently. This method was employed to measure the mechanical properties of DLC films deposited by {{{{ { {C }_{6 }H }_{6 } }} rf glow discharge. The was elastic modulus E increased from 94 to 169 GPa as the {{{{ { V}_{ b} / SQRT { P} }} increased from 127 to 221 V/{{{{ {mTorr }^{1/2 } }} Poisson's ratio was estimated to be abou 0.16∼0.22 in this {{{{ { V}_{ b} / SQRT { P} }} range. For the {{{{ { V}_{ b} / SQRT { P} }} less than 127V/{{{{ {mTorr }^{1/2 } }} where the plastic deformation can occur by the substrate etching process however the present method could not be applied.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.123-134
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• 1998

The study was performed to investigate the differences among various evaluation criteria for noise-induced hearing loss(NIHL). The subjects were 100 workers who had received detailed audiometric examinations after the periodic annual examination for hearing loss. The evaluation criteria included were as follows: The criterion I was NIHL of 50dB or greater at 4,000Hz in either ear which is one of the legal requirements for determining occupational hearing loss in Korea. The criterion II was NIHL of 40dB or greater by 4-divided classification(a+b+c+d/4 at 500Hz(a), 1,000Hz(b), 2,000Hz(c), 4,000Hz(d)) which is also one of the legal requirements for determining occupational hearing loss in Korea. The criterion III was NIHL of 31dB of greater by 6-divided classification(a+2b+2c+d/6) which is the workers' compensation standard. The criterion IV was NIHL of 40dB or greater by 6-divided classification(a+2b+2c+d/6), the criterion used to prohibite workers to be employed in the noisy workplace. The criterion V was NIHL of 40dB or greater by 3-divided classification(a+b+c/3) which is the guideline of the Japanes Labour Department. The results were as follows; 1. The percentage of workers with NIHL by the criterion I was the highest(96%) and covered all workers with NIHL diagnosed by other criteria. Therefore, this criterion was the most sensitive one for early detection of NIHL among various evaluation criteria. 2. The percentage of workers with NIHL by the criterion II was 29% of the subjects, but all of them could be diagnosed as having NIHL by the criterion I and 33.1% of the NIHL by the criterion III could not be covered by the criterion II. Thus, this criterion was not considered suitable as an initial step for determining occupational hearing loss. 3. The percentage of workers with NIHL by the criterion III was 45% of the subjects. This percentage was 46.9% of the NIHL by the criterion I and was estimated to cover 3.6% of all noise exposed workers. 4. The percentage of workers with NIHL by the criterion IV was 28% of the subjects, but 37.8% of the NIHL by the criterion III and 70.8% of the NIHL by the criterion I were not covered by the criterion. Therefore, these workers could have been employed in the noisy workplaces. 5. Employed relocation which was one of the post management methods was an option in the criterion I in Korea and in the criterion V in Japan. The number of NIHL by the criterion I was 6.7times greater than that by the criterion V. Thus, although employee relocation was not used exclusively, many more workers with NIHL could have been relocated. In conclusion, this study revealed that the criteria being used for managing occupational hearing loss showed a lack uniformity among them. In addition, since these criteria are all relied on the total threshold shifts caused by the noise exposure at the time of hearing test with no consideration given to the past noise exposure history nor age, it can be said that they are not an effective tool for occupational hearing loss management. Since legal requirements are usually followed after being diagnosed as having NIHL, it is recommended that a uniform diagnostic criterion should be used to minimize confusion. Pre-employment hearing tests should also be utilized so as to managing occupational hearing loss after employment rather than being used as a legal roadblock of prohibiting workers with mild hearing loss from being employed. Thus, what is needed is an establishment of a rational criterion for occupational hearing loss management rather than for legal requirements.

• The Journal of Internal Korean Medicine
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• v.1 no.1
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• pp.98-106
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• 1976

In order to study the effect of croton oil on the mucous cell in the mice intestin the experimental animals were injected with 0.1gm body weight of croton oil through intraperitoneally. They were sacrificed by ether anesthesia and obtained from distal small intestine and duodenum and colon, and fixed in 10% meutral formal. After embedded in paraffin, sectioned in 5 micro thickness, and stained with P.A.S (Periodic Acid Schiffis) reaction. The average number of the mucous cell was counted in each specimen over 20 fields under 450 magnification. The following results were obtained; 1) An average number of mucous cell began rapidly increase from 15 min and reached high average number after injection of croton oil of mucous cell from 30-60 min after injection. 2) An average number of mucous cell rapidly increase after injection of croton oil and were not reduced normal level by time lapsed 48 hrs. 3) The mucous cell showed with tape of time after injection of croton oil. A type and B type decrease and showed recovery C type decrease and recovery. 4) According to the above findings, it is presumed that croton oil accelerate secretion of mucin of the mucouse cell and production of mucin in growing mucous cell.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.2
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• pp.204-212
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• 2007

Purpose: The purpose of this study was to investigate the patient's perception of the nurse's behavior in protecting patient privacy and to make suggestions for medical facilities to increase protection of patient privacy. Method: The research was a survey study The data on protection of privacy in primary nursing, for physical privacy, of patient information and in private conversations were collected in October 2005 from 187 patients in a university hospital. Frequencies, means, t-test, ANOVA, and $x^2$-test were used to analyze the data. The SPSS 13.0 for Windows program was used. Results: The mean score for patients' perception of nurse protection of their privacy was 3.33. There were significant differences in perception of protecting patients' privacy according to gender for private conversation, according to level of education for all but physical nursing and for number of admissions for total score and for primary nursing. Conclusion: The results of this study suggest the following: a) Institutional polices and nursing guideline should be clearly stated as to the nurses' duty to protect patient privacy. b) Medical facilities should be arranged in a way that allows for the protection of patients' medical information, and should focus on patient privacy. c) It is necessary of nurses to receive periodic in-service education on protecting patient privacy.

• Journal of Power System Engineering
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• v.3 no.1
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• pp.55-59
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• 1999

Generally, T.G(Tacho-generator, Tachometer) sensor is used widely for sensing the angular velocity in rotary machine. By limitation of T.G sensor's structure, the sensed angular velocity include a periodic noise, and the noise is called "ripple" as an electrical term. To reduce the effecting of the ripple, many kinds of filters are designed and installed, but there is necessary a trade off between response time and adapted frequency band. In this paper, we propose a generalized observer to estimate an angular velocity from the output signal of T.G sensor. The generalized observer is proposed firstly for continue systems, and it is applied to DC servo motor with T.G sensor. For simulation, we measure T.G signals at 60, 400, 570 rpm respectively, and analysis those to obtain the resonance frequency of ripple by FFT method. To verify the effectiveness of the proposed algorithm, we compare the results with those of a RC low frequency band filter.