• Journal of the Optical Society of Korea
• /
• v.3 no.1
• /
• pp.20-22
• /
• 1999

We present numerically simulated results on stabilities of optical soliton transmission in highly-dispersion-perturbed optical fiber systems. We have found that the perturbation of dispersion along the transmission line does not significantly degrade stability of soliton transmission as long as the average soliton concept is obeyed.

• Smart Structures and Systems
• /
• v.9 no.6
• /
• pp.473-487
• /
• 2012

GPS has become an established technique in structural health monitoring. This paper presents the application of an on-line GPS RTK system on the Zhujiang Huangpu Bridge (China) for monitoring bridge deck and towers movements. In this study, both the form and functions of movements of the deck and towers of the bridge under affecting loads were monitored in lateral, longitudinal and vertical directions. Such movements were described in time and frequency domains by determining the trend, torsion, periodical of the series using probability density function (PDF). The results of the time series GPS data are practical and useful to bridge health monitoring.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.22 no.3
• /
• pp.80-94
• /
• 2009

Objective : The purpose of this clinical research is the investigation of the effects between acupuncture group(control group) and NURIEYE-1 group (experimental group) in myopia Methods : Comparison clinical study was conducted with the randomly arranged 32 patients for acupuncture group(control group) and NURIEYE-1 group(experimental group). For effectiveness evaluation, eye sight test, MQOL and DITI were tested three times with visits for every 4 weeks. With SAS, Statistical analysis was performed by using paired t-test and two sample t-test. Statistical significance was achieved with less than 5% probability (p<0.05). Result : 1. There was no significant effect from the eye sight comparison between the two group. We had improved results in average with MQOL, however, there was no statistical significance. Though there was also no significant result with DITI average comparison between two group, we witnessed significant effect in some part of MQOL. 2. Nevertheless Periodical comparison test showed weak significance with eye sight and DITI, significant effect was found in some part of MQOL. 3. With periodical comparison tests, there were significant effects in eye sight, MQOL and DITI with the experimental groups and control groups, respectively. Conclusion : There was no significant eye sight improvement. However, with acupuncture point stimulation, we think there are some positive effects for the relaxation of excessive stress in eyes.

• The Journal of the Korea Contents Association
• /
• v.16 no.8
• /
• pp.681-692
• /
• 2016

What is the socio-cultural meaning of the 1980s' Korean robot animations? What is the periodical backgrounds making this meaning? This study has attempted to lay the foundation stone of the answer for the questions. To do that, this study selected Roboteu King(Yeong-rang Bae, 1980) and Super Titan 15(Seung-cheol Park, 1983) as the objects of the textual analysis. To grasp the periodical identity, it has examined the cold war ideology that has been the basis of the political and economic environments of Korea. Findings are as follows. Korea was vulnerable to general environments after the Korean War; accordingly, Korea took the-dependence-on-the-US strategy in terms of various aspects including national security, scientific technology, and industry economy. This kind of socio-cutural condition was represented through the narratives of the early 1980s' Korean robot animations. Their narratives including the advance of plots, the roles of Korean protagonists, the technological gap between the planets and earth, and so forth were quite dependent on extraterrestrials and contained anticommunist ideology.

• Journal of the Korean Society for Railway
• /
• v.19 no.3
• /
• pp.397-407
• /
• 2016

This study analyzed the efficiency change and the factors affecting productivity change for the six railway operation corporations that are local public enterprises; study was performed with the DEA-CCR Model and Malmquist Productivity Index, using data collected from 2010 to 2014. Since it was not feasible to collect data on the operating expenses and the number of employees of each of the lines, the efficiencies of each operation corporation were analyzed by integrating the operation corporations, and the Malmquist Productivity Index was used to investigate the trend of the periodical productivity change. Average efficiency for urban railway operation corporations was found to be higher in the case of the bigger corporations. In 2014, the Seoul Metro and the Daejeon Metropolitan Express Transit Corporations were analyzed and found to be the most efficient operation corporations. The Malmquist Productivity Index was used to determine the periodical change; the average MPI was 1.06, with a continuous increase of productivity. The analysis showed that changes of technology were generally more obvious than change of technology efficiency for all six operation corporations.

• Journal of Preventive Medicine and Public Health
• /
• v.11 no.1
• /
• pp.110-122
• /
• 1978

A study on the morbidity of syphilis among 729 workers in Po Hang and Ul San Industiral Complexes at the routine periodical examination was performed. In addition to the morbidity, factors related to the disease infection such as educational level, religion, preventive measures taken by the workers, history of urethritis, and so on were studied and analysed to check significant relation. The results were as follows: 1. VDRL and RPR tests were undertaken to determine the sensitivity and specificity of RPR test which was utilized for all the workers studied. It revealed 86.4% of sensitivity and 87.7% of specificity from RPR test, and 81.8% of sensitivity and 90.1% of specificity from the VDRL test compared with RPCF test. There were 87.4% of agreement rate between RPR and VDRL. Actually, RPR was more sensitive but less specific than VDRL, and found to be a satisfactory screening test for syphilis especially in the fields. 2. Among the workers in Po Hang Area 24.0% of them revealed reactive result, and in Ul San Area 5.2% revealed reactive result showing 4.6 times of risk among workers in Po Hang Area. 3. There were no statistically significant differences between RPR reactive rates and personal characteristics such as educational level, religion, history of urethritis experience, history of coitus with prostitute, and preventive measures of V.D. taken by workers if evaluated by area of Po Hang and Ul Srn separately. 4. V.D. could be encountered as an occupational disease in certain conditions of working places and the psychosocial problems of workers. And so, it is necessary that all the workers working in special estates such as in Po Hang Industrial Complex should be checked to be screened out by RPR test at periodical examinations and part of pre-employment examination also should include RPR test to be compared with. Regardless of the workmen's compensation, establishment of V.D. treatment clinic or system for such industrial workers is urgently needed. Health education regarding V.D. is another subject to be performed.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.19 no.1
• /
• pp.79-86
• /
• 1995

The structural materials for cryogenic technology have been recently developed to support the many modern large-scale application from superconducting magnets for nuclear fusion reactor, magnetic levitation railway to LNG tankers. However it is pointed out that quenching phenomenon is one of the serious problems for the integrity of these applications, which is mainly attributed to the rapid temperature rising in the material due to some extrinsic factors of structures. From the viewpoint of fracture mechanics, it is therefore very important to clarify the mechanism of temperature rising of structural material due to cyclic loading at cryogenic temperature. From this purpose, fatigue test was carried out for high manganese steel at liquid helium temperature(4.2K) using triangular stress waveform to identify both the mechanism of temperature rising near crack tip and the effect of loading stress waveform on temperature rising near crack tip and the effect of loading stress waveforms on temperature rising. As the results, two types of temperature rising, that is, regular and burst types were observed. And a periodical temperature rising corresponding to the stress waveforms was also found. The peaks of the temperature rising were recorded near both the maximum and the minimum values of the applied stress. The sudden temperature rises, which indicated the higher values than those of periodical temperature rises under the repetition of stress, were observed at the final region of crack growth. It was shown that the peak values of the temperature rising increased with stress intensity factor range.

• The Journal of Engineering Geology
• /
• v.30 no.3
• /
• pp.303-314
• /
• 2020

Bottled water companies submit monthly hydrologic data including periodical environmental effects investigation, daily water production capacity, water production, water level, water chemistry (pH, EC, temperature) per hour and strictly manage groundwater by periodical analyses. Thus few problems concerning drawdown due to excess intake of groundwater take place. Nevertheless, bottled water companies are imprinted as a contribution to civil affairs resulted regarding groundwater near the companies. Therefore, a new method is required during water balance analysis in environmental effects evaluation, which should be compatible with the evaluation by hydrologic experts as well more accessible to non-experts. In this study, water level of surface water and recharge rate in subcatchment where water production wells are located were measured and monthly baseflow rates were separated from normal streams. Besides, recharge properties of groundwater and surface water in the same catchment area were estimated using analyses of oxygen and hydrogen isotopes in groundwater (production well), surface water, and rainfall.

• Journal of Korean Library and Information Science Society
• /
• v.32 no.3
• /
• pp.275-305
• /
• 2001

This study is to analyze factors affecting collection size by the type of materials of university libraries in Korea. The results of this study are summarized as follows; ①Factors affecting library holdings in volumes: national univ. - volumes loaned, total number of courses, library materials expenditure; private univ. - undergraduate enrollments, library materials expenditure, volumes loaned, number of graduate departments; total univ. - undergraduate enrollments, volumes loaned, library materials expenditure ②Factors affecting periodical titles: all the libraries - graduate enrollments ③Factors affecting the size of nonbook materials: national univ. - graduate enrollments, number of undergraduate departments; private and total univ. - volumes loaned ④Factors affecting volumes added: national univ. - volumes loaned, number of graduate courses; private univ. - number of undergraduate enrollments; total univ. - volumes loaned ⑤Factors affecting the size of nonbook materials added: national univ. - number of graduate enrollments, number of undergraduate departments; private and total univ. not extracted.

• Journal of Korean Library and Information Science Society
• /
• v.15
• /
• pp.113-151
• /
• 1988

The enumerative classification schemes do not represent the tiny mass of knowledge embodied in a article in a periodical or in a chapter or a paragraph of a book. But today's information centers regard a tiny spot of knowledge embodied in a article as a class. we call this micro-thought. But the enumerative classification are manual systems, it cannot be a n.0, pplied to the automation of classification. The purpose of this study is to build a general principle for the automatic book-classification which can be put to use in library operation, and to present a methodology of the automatic classification for the library. The methodology used is essentially theoretical, Published works by and about Ranganathan, especially 6th edition of the CC were studied, analyzed. The principle of automatic book classification derived from the analysis of colon classification and facet combinations. The results of this study can be summarized as follows ; (1) This study confined the fields of library science and agriculture. (2) This study represent a general principles for the automatic book classification of library science and agriculture. (3) Program flowcharts are designed as a basis of system analysis and program procedure in library science and agriculture. (4) The principles of the automatic classification in library, science is different from that of agriculture. (5) Automatic book classification can be performed by the principle of faceted classification, by inputting the title and subject code into a computer. In addition, the expected value from the automatic book-classification is as follows (1) The prompt and accurate of classification is possible. (2) Though a book is classified in any library, it can have same classification number. (3) The user can retrieve the classification code of a book for which he or she wants to search through dialogue with the computer. (4) Since the concept coordination method is employed, a tiny mass of knowledge embodied in a article in a periodical or in a chapter or a paragraph of a book can be represented as a class. (5) By performing automatic book-classification, the automation of library operation can be completed.