• Radiation Oncology Journal
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• v.6 no.1
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• pp.85-91
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• 1988

For the physical characterization of neutron beam, dosimetric measurements had been performed to obtain physical data of KCCH cyclotron-produced neutrons for clinical use. The results are presented and compared with the data of other institutions from the literatures. The central axis percent depth dose, build-up curves and open and wedge isodose curve values are intermediate between that of a 4 and 6 MV X-rays. The build-up level of maximum dose was at 1.35cm and entrance dose was approximately $40\%$. Flatness of the beam was $9\%$ at Dmax and less $than{\pm}3\%$ at the depth of $80\%$ isodose line. Penumbra begond the $20\%$ line is wider than corresponding photon beam. The output factors ranged 0.894 for $6\times6cm$ field to 1.187 for $30\times30cm$ field. Gamma contamination of neutron beam was $4.9\%$ at 2 cm depth in $10\times10cm$ field.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.29-42
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• 1999

The SASW (Spectral-Analysis-of-Surface-Waves) method, which evaluates the stiffness structure of the subsurface and structures nonintrusively and nondestructively, has been successfully used in the civil engineering applications. However, the SASW method assumes that the subsurface or structures consist of horizontal multi-layers, so that the method has some difficulty in continuously evaluating the integrity of a tunnel lining and a pavement system. This difficulty prevents the SASW method from being used to generate a tomographic image of stiffness for the subsurface or structures. Recently, the GPR technique which has the advantage of continuously evaluating integrity of the subsurface and structures has been popular. This advantage of GPR technique initiated the efforts to make the SASW method, which is superior to GPR and other nondestructive testing methods due to its capability of evaluating stiffness and modulus, be able to do continuous evaluation of stiffness structure, and the efforts finally lead to the development of \ulcornerTomographic SASW Technique.\ulcorner Tomographic SASW technique is a variation of the SASW method, and can generate a tomographic image of stiffness structure along the measurement line. The tomographic SASW technique was applied to the investigation of lateral variability of a sand box placed by the raining method for the purpose of verifying its effectiveness. Tomographic SASW measurements on the sand box revealed that the investigated sand box has different shear stiffness along the measurement line, which gave a clue of how to make a better raining device.

• Journal of the Korean Society of Radiology
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• v.4 no.2
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• pp.21-25
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• 2010

Recently, various semiconductor compounds as radiation detection material have been researched for a diagnostic x-ray detector application. In this paper, we have fabricated the CdS detecton sensor that has good photosensitivity and high x-ray absorption efficiency among other semiconductor compounds, and evaluated the application feasibility by investigating the detection properties about energy range of diagnostic x-ray generator. We have fabricated the line voltage selector(LCV) for a signal acquisition and quantities of CdS sensor, and designed the voltage detection circuit and rectifying circuit. Also, we have used a relative relation algorithm according to x-ray exposure condition, and fabricated the interface board with DAC controller. Performance evaluation was investigated by data processing using ANOVA program from voltage profile characteristics according to resistive change obtained by a tube voltage, tube current, and exposure time that is a exposure condition of x-ray generator. From experimental results, an error rates were reduced according to increasing of a tube voltage and tube current, and a good properties of 6%(at 90 kVp) and 0.4%(at 320 mA) ere showed. and coefficient of determination was 0.98 with relative relation of 1:1. The error rate according to x-ray exposure time showed exponential reduction because of delayed response velocity of CdS material, and the error rate has 2.3% at 320 msec. Finally, the error rate according to x-ray dose is below 10%, and a high relative relation was showed with coefficient of determination of 0.9898.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.29-42
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• 2017

Jeongeuihyanggyo(旌義鄕校) is a kind of traditional, Confucian cultural landscapes that is located in Jeju special self-governing province. Its historical background illustrates that the first erection was started at Goseong-li of Seongsan-eup(城山邑 古城里) at Taejong(太宗) of 16 years(1417) and it moved to the west gate of Hyunseong(縣城) at Heojong(憲宗) of 15 years,(1849) Joseon. The aim at this study is to reveal characters of these Confucian Spatial Composition and Order, which are valuable resources that can be created into the cultural contents. The results demonstrate the characters of the Confucian cultural landscape as followings; the changing process of new building and its relocation, the utilization of antique maps in location interpretation of Jeongeuihyanggyo, Confucian symbolic elements of it, the spatial compositions and layouts of its buildings, physical structures, main buildings and their characters, locational points of topographic profile, changes of axial line at Daeseongjeon(大成殿), the D/H ratio of its courts. This study can show that Jeongeuihyanggyo is a case for realizing the Confucian reformation to enhance Seongeup Hyun's education standard considering the locality of the site which is an isolated island like Jejudo(濟州島). The author can see that the example of Confucian space is applied to various layout techniques, both horizontally and vertically, in a limited space condition of being in the castle. Therefore, it is necessary to revive this point so that it can utilize unique Confucian cultural landscape possessed only by Jeongeuihyanggyo.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.589-600
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• 2021

The present study investigated the effect of perch material type (wood and steel) on performance, blood characteristics, and feather pecking. A total of 1,700, one-day-old female Hy-Line brown chicks were evenly assigned to two treatments (wood and steel). The body weight and uniformity of birds were investigated over a 10-week experimental period. Blood characteristics and feather pecking was conducted at week 10. The wood perch treatment (WP) and steel perch treatment (SP) did not differ in their body weight, uniformity, and serum biochemical profile (except inorganic phosphorus) of pullets. Inorganic phosphorus on serum in WP significantly higher than that in SP (P<0.05). Blood corpuscle composition (leukocyte, erythrocyte, and Heterophil / Lymphocyte ratio) of pullets did not show any significant differences among treatments at week 10. Serum corticosterone and feather score that is stress and welfare indices were not affected by the type of perch material. In conclusion, our results suggest that performance, blood characteristics, and feather pecking of pullets were not affected by the perch material type. The results of this study can serve as basic data for investigating the effects of perch type on layer pullets.

• Tuberculosis and Respiratory Diseases
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• v.59 no.5
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• pp.510-516
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• 2005

Backgroud : Lung cancer is the leading cause of cancer deaths in Korea and the number of lung cancer deaths is increasing. The higher response rates, decreased toxicity and improved performance status of the first-line treatments have resulted in an increased number of patients becoming candidates for second-line therapy. Several new antineoplastic agents, including gemcitabine, docetaxel and paclitaxel, have recently demonstrated second-line activity. This phase II study evaluated the efficacy and toxicity of gemcitabine and vinorelbine as combination chemotherapy for Korean patients with NSCLC as a second-line treatment. Methods : Sixty response-evaluable patients were enrolled from December 2000 to July 2003. We conducted a phase II study of a combination gemcitabine and vinorelbine chemotherapy for patients with histologically confirmed NSCLC that was stage IIIB and IV disease at the time of diagnosis, and the disease had progressed onward or the patients had relapsed after first-line platinum-based chemotherapy. They were treated with intravenous gemcitabine $1000mg/m^2$ and intravenous vinorelbine $25mg/m^2$ on days 1 and 8. This chemotherapy regimen was repeated every 3 weeks. Results : A total of 215 cycles of treatment were given and the mean number of cycles was 3.6 cycles. All the patients were evaluable for the toxicity profile. The response rate was 10% according to the WHO criteria. The median progression free survival was 3.8 months and the median survival time was 10.1 months. The 1-year survival rate was 32.9%. Grade III and IV neutropenia were seen in 20 (33.3%) and 7 (11.7%) patients, respectively. Conclusion : The combination of gemcitabine and vinorelbine is active and well tolerated as a second-line therapy for patients with advanced nonsmall cell lung carcinoma.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.4
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• pp.105-111
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• 2010

This paper proposes the recursive algorithm for passive proximity detection system based on signal strength. The system is designed to be used in the smart medicine chest in order to provide location-based service for the senior personnel. Due to the system profile, single receiver and uni-direction communication are applied over the signal attenuation model for the determination of user existence within certain proximity. The performance of conventional methods is subjective to the sight between the transmitter and receiver unless the direction of target is known. To appreciate the temporal and spatial locality of human subjects, the authors present exponential moving average (EMA) to compensate the unexpected position error from the direction and/or environment. By using optimal parameter, the experiments with EMA algorithm demonstrates 32.26% (maximum 40.80%) reduction in average of the error probability with 50% of consecutive sight in time.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.547-551
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• 2010

In this paper, Double rectangular patch with 4-bridges is investigated for solution of IEEE 802.11b/g(2.4GHz) and 802.11a(5.7GHz). Rectangular patch for 5.7GHz frequency band is printed on the PCB substrate and connected to another rectangular patch for 2.4GHz frequency band with 4-bridges to obtain dual band operation in a antenna element. The proposed antenna has a low profile and is fed by $50{\Omega}$ coaxial line. The dielectric constant of the designed antenna substrate is 3.27. Two rectangular patches have each resonance frequencies that are 2.4GHz and 5.7GHz. A dual-band characteristic is shown as connecting two rectangular patch using four bridges. Also, the proposed antenna is shown input return loss that is below -10dB at 2.4GHz and 5.7GHz of WLAN(Wireless LAN).

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.15-20
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• 2020

In this paper, delay diffusion for exhibition hall and conference room was measured and analyzed in the indoor environment of the building. Scenarios for the indoor environment of the two buildings were written. also, the system configuration and measurement methods were conducted under the same conditions. The measurement conditions were set to 3 GHz and 6 GHz of center frequencies and analysis band selected 2 GHz. The measurement system consisted of vector network analyzer, power amplifier, omni-directional transmit and receive antenna, and transmission line. According to the indoor environment scenario of the two buildings, the location of the receiving antenna was divided into three zones based on the location of the transmitting antenna and this was measured at 1 m intervals according to 18 locations. The power delay profiles, RMS delay spread, and K-factor results of two buildings were compared and analyzed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4499-4505
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• 2014

Glioblastoma, the most aggressive and malignant form of glioma, appears to be resistant to various chemotherapeutic agents. Hence, approaches have been intensively investigated to targeti specific molecular pathways involved in glioblastoma development and progression. Aloe emodin is believed to modulate the expression of several genes in cancer cells. We aimed to understand the molecular mechanisms underlying the therapeutic effect of Aloe emodin on gene expression profiles in the human U87 glioblastoma cell line utilizing microarray technology. The gene expression analysis revealed that a total of 8,226 gene alterations out of 28,869 genes were detected after treatment with $58.6{\mu}g/ml$ for 24 hours. Out of this total, 34 genes demonstrated statistically significant change (p<0.05) ranging from 1.07 to 1.87 fold. The results revealed that 22 genes were up-regulated and 12 genes were down-regulated in response to Aloe emodin treatment. These genes were then grouped into several clusters based on their biological functions, revealing induction of expression of genes involved in apoptosis (programmed cell death) and tissue remodelling in U87 cells (p<0.01). Several genes with significant changes of the expression level e.g. SHARPIN, BCAP31, FIS1, RAC1 and TGM2 from the apoptotic cluster were confirmed by quantitative real-time PCR (qRT-PCR). These results could serve as guidance for further studies in order to discover molecular targets for the cancer therapy based on Aloe emodin treatment.