• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1609-1617
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• 2019

Described in this paper is a design of hardware accelerator for implementing public-key cryptographic protocols (PKCPs) based on Elliptic Curve Cryptography (ECC) and RSA. It supports five elliptic curves (ECs) over GF(p) and three key lengths of RSA that are defined by NIST standard. It was designed to support four point operations over ECs and six modular arithmetic operations, making it suitable for hardware implementation of ECC- and RSA-based PKCPs. In order to achieve small-area implementation, a finite field arithmetic circuit was designed with 32-bit data-path, and it adopted word-based Montgomery multiplication algorithm, the Jacobian coordinate system for EC point operations, and the Fermat's little theorem for modular multiplicative inverse. The hardware operation was verified with FPGA device by implementing EC-DH key exchange protocol and RSA operations. It occupied 20,800 gate equivalents and 28 kbits of RAM at 50 MHz clock frequency with 180-nm CMOS cell library, and 1,503 slices and 2 BRAMs in Virtex-5 FPGA device.

• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.385-393
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• 2022

In this paper, we consider univariate time series models that are well known in the field of forecasting and we study on forecasting performance for their simple combinations. The univariate time series models include exponential smoothing methods and ARIMA (autoregressive integrated moving average) models, their extended models, and non-seasonal and seasonal random walk models, which is frequently used as benchmark models for forecasting. The median and mean are simply used for the combination method, and the data set used for performance evaluation is M3-competition data composed of 3,003 various time series data. As results of evaluating the performance by sMAPE (symmetric mean absolute percentage error) and MASE (mean absolute scaled error), we assure that the simple combinations of the univariate models perform very well in the M3-competition dataset.

• Radiation Oncology Journal
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• v.14 no.2
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• pp.105-113
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• 1996

Purpose : To improve treatment modality and results by analysis of clinical characteristics, local control, survival and recurrence rate in limited stage small cell lung cancer. Materials and Methods : patients with limited stage small cell lung cancer were treated with combined radiation and chemotherapy from Feb. 1986 to Dec. 1992 at the National Medical Center We followed up on 21 patients ($81\%$), who were mostly irradiated with 4,000-5.000cGy ($75\%$ of all Patients) in the results by the analysis retrospectively. Survival rate was evaluated by the Kaplan-Meier method Results : Mean survival of irradiated patients with limited small cell lung cancer was 12 months. 1-rear and 2-rear survival rate were $65.3\%$ and $15.4\%$ Tumor response rate and median survival after combined chemotherapy and irradiation were the following: $50\%$ and 15 months of complete response, and $23\%$ and 11 months of partial response respectively. Response rates by radiation dose were $66\%$ for below 4,000cGy $69\%$ for between 4,000-5,000cGy and $86\%$ for above 5,000cGy. 21 of all patients showed treatment failure($81\%$) which as appeared 9 of local failure.9 of distant failure and 3 of local and distant failure. Conclusion : Local response rate after induction chemotherapy alone in limited stage of small cell lung cancer was $54\%$. Furthermore it was increased to $73\%$ after adding of radiation. We have to increase radiation dose above 5,000cGy and need to try new effective chemotherapy agents for the improvement of local control and survival rate and also will try concurrent chemoradiotherapy in near time.

• Economic and Environmental Geology
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• v.35 no.5
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• pp.395-406
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• 2002

The sixty natural springs and community wells used as a drinking water in the Daejeon area are mainly located at the parks and the natural green districts. The purpose of this study is to investigate the characteristics of water quality and the contamination of the springs and the wells, and to suggest the management strategy for the springs and wells. For this study, we undertook water quality data from Daejeon City. According to the statistic analysis of water quality data, unacceptable rate as a drinking water was about 28 percent in 1999 and 24.5 percent in 2000, respectively. Major unacceptable factor is coliform, and others are bacteria, yersinia, color, turbidity, Fe and F. The unacceptable rate shows a roughly positive relationship with precipitation, that is, it shows highest rate during a rainy season between June and September. The major contamination source is likely to be the excrement of wild animals around natural springs and wells. Most of springs are vulnerable to the contamination of coliform and bacteria because of short residence time and shallow circulation in subsurface environment. The water samples collected from 31 springs or wells show weak acidic pHs, the electrical conductivity ranging from 63 to 357 $\mu\textrm{S}$/cm, and the hydrochemical types of Na(Ca)-HC0$_3$ and Ca-HC0$_3$. The groundwater samples of low total dissolved solid(TDS) belong to Na(Ca)-HC0$_3$. type, and the groundwater of high total dissolved solid is shifted towards Ca-HC0$_3$ type in the chemical composition. These hydrochemical characteristics indicate that most natural springs is in the early stage of geochemical evolution. The natural springs should be closed during a rainy season, which shows a high contamination rate. We suggest that a protection barrier around the springs should be built to keep wild animals away from the springs.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.3.2-3
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• 1979

Bone conduction loss is one of the most common complication in chronic otitis media, and is mostly high frequency loss. Of 233 tympanomastoidectomy ears, 187 ears were considered eligible for this study. A histopathological change was examined in the natural otitis media of guinea pigs. It is our intention to analyze the pattern of bone conduction loss in chronic otitis media, and to correlate this findings with clinical and pathological changes in human and animal otitis media. l) In unilateral cases, a significant difference in bone conduction threshold was observed between normal and diseased ears, and between each frequency with significant interaction between 2KHz and 4KHz (p 0.01). 2) Using one way analysis of variance, mean bone conduction was compared with the duration of disease. We observed a significant difference (p 0.05) between each group of duration, except between 11-15 and 15-20 years group. 3) A comparison of bone conduction between stapes loss group and intact stapes group revealed significant t ratio (p 0.01) at each frequency. The effect of stapes loss on each frequency was evaluated, using one way analysis of variance. there were significant difference(p 0.05) between 250Hz and 500Hz. and between 2KHz and 4KHz. 4) A comparison of bone conduction between round window obliteration and nonobliteration group revealed significant t ratio (p 0.01) at each frequency. Using one way analysis of variance. the effect of round window obliteration was evaluated in each frequency. We observed significant difference (p 0.05) between 250Hz and 500Hz. and between 2KHz and 4KHz. 5) A comparison of bone conduction between cholesteatoma and non -cholesteatoma group revealed significant t ratio (p 0.01) only in 2KHz and 4KHz. No significant differency was observed in mean bone conduction. 6) In a histopathological study of natural otitis media in guinea pig, we observed inflammatory infiltration of the round window membrane, serofibrinous precipitate in the scala tympani, and degeneration of the organ of Corti most significant near the basal turn. These changes would explain high tone bone conduction loss in the process of chronic otitis media.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.6.2-6
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• 1979

Foreing bodies of the esophagus and tracheobronchus are likely to occur whenever a child places an inedible object in the mouth and are common in the older age group particularily in edentulous individuals or preexisting disease. Our department had already reported the statistical survey at first in 1954, successively in 1962, 1963 and 1968, respectively according to the age, sex, variety of foreign bodies, location and duration of the lodgement. Now, we have experienced the new 186 cases during the consecutive 5 year period from January 1973 to December 1977 and reported as a 5th report comparing with previous report. The results were as follows. 1. In the incidence of foreign bodies, coins were the most common and pointed metal, disc, bony fragment were followed in order in the esophagus while the peanut and corn were common in the air passage. 2) 79 cases (56.4%) were males and 61 cases (43.6%) were females in the esophagus, which was not a significant difference to note. But in the air passage, males accounted for 33 cases (71.7%) compared to 13 cases (28.3%) of females. 3) In the aspect of age incidence, child 10 years or under accounted for almost all cases in the esophagus as well as in the air passage. 4) In the location of foreign bodies in the esophagus, the first narrowing was the most common, while in the air passage right bronchus had a high incidence but the difference of incidence between right bronchus and left bronchus was not remarkable. 5) The duration of lodgement was 24 hours or less in more than half of the all cases. 6) In the aspect of kind of coin, 10 won coins accounted for majority of the cases (67.0%) but the incidence of 100 won coins were tend to increase gradually in these years.

• Journal of Hospice and Palliative Care
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• v.4 no.1
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• pp.4-13
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• 2001

Purpose : Since the acquired immune deficiency syndrome (AIDS) was first recognized in the United States in the summer of 1981, the number of these patients has been increasing in the world. But do not find out a cure and a vaccine for ARS (5). And so, the best treatment for AIDS is the prevention. People can find out accurate knowledge about AIDS, and they can prevent themselves from AIDS approximately 100%. In this study, we investigate with AIDS knowledge and attitudes in unmarried young men (<24 age) and suggest accurate preventive education for AIDS and good sexual behaviors. Methods : Un-married young soldiers and college students who were not diagnosed as AIDS until June 30, 2000 were included in the study. The study included a total of 923 men. A self evaluation questionnaire, included questions on 36 items(the part of demographic data - 9; the part of knowledge - 20; the part of attitudes - 8), was drawn up by three physicians. The demographic data, AIDS knowledge and attitudes were analyzed by chi-square analysis, and the total score of AIDS knowledge - comparison according to demographic factors and attitudewere analyzed by one-way ANOVA test. Results : In demographic characteristics, as for the first recognized time of AIDS, most of men knew it when they were in their middle school, as for sources of information on AIDS, most of them knew it through the TV-media, and as for the educational need about AIDS, most of them agreed with it. In AIDS knowledge, mean scores were $14.0{\pm}1.8$ (70.3%). Items of the misconceptions concerning AIDS, reported as less than 50% correct answers, were 6 among 20 items (30%). In AIDS attitudes, as for the item about that if I will be an AIDS patient, I will have an AIDS treatment, it showed that the number of men agreed with 759 (82.2%), and as for the item about that I will help for AIDS patient even though I don't know him, it showed that the number of them agreed with 412 (45.8%). In correlation of AIDS knowledge and demographic factors, the mean scores of knowledge of men with higher than college degree were higher than them of others. The mean scores of knowledge of men with total income of family with more than US$1667 were higher than them of others. The mean scores of knowledge of men with sources of information on AIDS through the TV-media were higher than them of others. And the mean scores of knowledge of men with past medical history of STD(sexually transmitted disease) were higher than them of others. Conclusions : The higher the knowledge he has, the lower the possibility of risk and the more positive the attitude he has. And then we think that the education program for AIDS will be included as a regular part of the curriculum in high school, and young men must be effectively educated by it.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.1
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• pp.124-132
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• 2002

Daebangpung-tang(DBPT) is one of the prescriptions used for the treatment of rheumatoid arthritis(RA) in oriental medicine. The present study aimed to examine the analgesic effect of DBPT on a rat model of CFA-induced arthritis, which is not identical to human auto-immune arthritis although it does have many features in common with RA, and the relation between DBPT-induced analgesia and steroid hormones. CFA-induced arthritis rat model used to test the effect of DBPT was chronic pain model. After the induction of arthritis, rats subsequently showed a reduced stepping force of the affected limb for at least the next 18 days. The reduced stepping force of the limb was presumably due to a painful knee, since oral injection of indomethacin produced temporary improvement of weight bearing. DBPT dissolved in water was orally administrated. After the treatment, behavioral tests measuring stepping force were periodically conducted during the next 4 hours. DBPT produce significant improvement of stepping force of the hindlimb affected by the arthritis lasting at least 3 hours. The magnitude of this improvement was equivalent to that obtained after an oral injection of 3mg/kg of indomethacin and this improvement of stepping force was interpreted as an analgesic effect. The reduced stepping force was divided into three stages(10-30g, 30-50g, and 50-70g). All experiments was performed at 50-70g of stepping force, since both DBPT and indomethacin showed the most excellent analgesic effect at 50-70g of stepping force. DBPT produced the improvement of stepping force of the affected hindlimb in a dose-dependent manner and showed analgesic effect on neuropathic pain as well. DBPT-induced analgesic effect could not be blocked by systemic injection of steroid antagonist mifepristone. The present study suggest 1) that DBPT produces a potent analgesic effect on the chronic knee arthritis pain model in the rat and 2) that steroids system does not mediate DBPT-induced analgesia.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.47-53
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• 1977

Bacterial diseases of soybean has been recognized as a limiting factor of soybean production in Korea as it was estimated to cause around 10 percent of yield losses annually. The purpose of the study is to obtain information on the diseases through proving the kinds of pathogens and epidemiology, The wire brush method and multineedle appeared to be the best way of inoculation under all circumstances. Wire brush method, especially, was effective in shortening the incubation period and manifesting the lesion development by introducing more inoculum per unit of area. In case of spray inoculation it was necessary to apply a small amount(1 : 1,000) of wetting agent, twin-20, otherwise it was unabled to produce the diseases under field conditions. Two kinds of bacterial diseases caused by Pseudomonas glycinea and Xanthomonas phaseoli var. sljense were found from surveyed areas in Kore. Wild fire disease on soybean caused by Pseudomonas tabaci had not detectable during the experiment although there were several reports on the disease from other countries. when the pathogens were introduced into sterile soil, bacterial leaf blight pathogen could exsisted until 30 days while bacterial pustule pathogen survived only 4 days under the natural conditions of later June. Both bacteria, however, could produce the disease after more than 10 months period of storage in refrigerator when they were exsisted in infected plant tissues. In warehouse, non-temperature controlled, the bacteria lose their infectability within 6 months period from October to April even though they exsisted in infected tissues. Surface infested seeds with the pathogens could not produced the diseases on seedling stages of soybean plants when the seeds were planted in sterile soil after inoculation by dipping the seeds into bacterial suspensions, although germination was depressed by the pathogens when the seeds were planted on agar media.

• Tuberculosis and Respiratory Diseases
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• v.62 no.3
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• pp.217-222
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• 2007

Talc pleurodesis is a safe and effective treatment for a recurrent malignant pleural effusion. However, acute hypoxemia, pulmonary edema or acute respiratory failure can develop in a small number of patients. We report 2 patients who developed fatal hypoxemia after talc pleurodesis which was necessary the control recurrent pleural effusion. The first case was an 18-year old male diagnosed with Ewing's sarcoma with bilateral lung metastases and pleural effusion. The performance status was ECOG (Eastern Cooperative Foncology Group) grade 3. Fever along with hypoxemia and leukocytosis developed 10 hours after the second talc pleurodesis on the right side for an uncontrolled pleural effusion, The patient died from respiratory failure after 13 days. The second case was a 66-year old female diagnosed with non-small cell lung cancer with a bone metastasis. Two weeks after systemic chemotherapy, she complained of dyspnea, and a pleural effusion was observed on the right side. Her performance status was ECOG grade 3. Talc pleurodesis was performed for recurrent pleural effusion, but hypoxemia developed 6 days after pleurodesis and she died from respiratory failure 10 days after pleurodesis. In conclusion, talc pleurodesis should be performed very carefully in patients with a poor performance status, in cases with repeated pleurodesis, bilateral pleural effusion, recent chemotherapy, radiotherapy and when there are parenchymal metastatic lesions present.