The investigation of water quality was performed at the upstream of Seomjinkang dam reservoir for the examination of pollutant load characteristics of the reservoir watershed during flood and normal flow periods. The highest water quality concentration was occurred at Y ongsan during normal flow period where it has been more polluted by population and livestock than other sites. Pollutant load varied depending on the sampling site, rainfall intensity and antecedent precipitation during the rainy period. Based on the water quality data measured from 1998 to 1999, the average concentration during rainy period was much higher than that of non~rainy period: BOD was 1.2~1.4 times, COD 1.2~1.7 times, SS 2.6~5.4 times, T-N 2.3~3.0 times, and T-P 2.4~7.5 times respectively. When the pollutant load measured during 7 different rainy periods in 1999 was compared with total pollutant load in 1999, the BOD and COD load measured during the 7 different rainy periods were 28% that is about 1.6 times as high as those of 1999. On the other hand, the rainfall amount measured during the 7 different rainy periods was about 17.5% of total rainfall amount in 1999. The total pollutant load of TN and TP measured during the 7 different rainy periods was almost 50% of total TN and TP loads in 1999. In case of SS, it was 72.8%. It was concluded that the inflow of pollutants into the lake during the rainy period held a high portion of total inflow in 1999. It was suggested that long~term water quality monitoring be performed to better quantity pollutant load to the lake especially during rainy periods.eriods.
We present an experimental framework to analyze the physical reactions and causal factors of Visually Induced Motion Sickness (VIMS) using electroencephalography (EEG) signals and vital signs. We studied eleven subjects who are voluntarily participated in the experiments and conducted online and offline surveys. In order to simulate videos including global motions that could cause the motion sickness, we extracted global motions by optical flow estimation method from hand-held captured video recordings containing intense motions. Then, we applied the extracted global motions to our test videos with action movies and texts. Each genre of video includes three levels of different motions depending on its intensity. EEG signal and vital sign that were measured by a portable electrocorticography device and an electronic monometer in real time while the subjects watch the videos including ones with the extracted motions. We perform an analysis of the EEG signals using Distance Map(DM) calculated by correlation among each channel of brain signal. Analysis using the vital signs and the survey results is also performed to obtain relationship between the VIMS and causal factors. As a result, we clustered subjects into three groups based on the analysis of the physical reaction using the DM and the correlation between vital sign and survey results, which shows high relationships between the VIMS and the intensity of motions.
The purpose of this study was to the determine the optimal torques values to tighten the retaining screw. 3-different implant system tested were as follows : Branemark implant system$(3.75mmD{\times}100mm)$, Steri-Oss implant system$(3.8mmD{\times}10mm)$. One fixtures of each implant system was mounted into the epoxy resin block and abutment/superstructure complex was constructed. Eighty dental college students(male : 40, female : 40) of Chosun University were selected and were asked to tighten the retaining screws. Abutment/superstructure complex of each implant system was tightened to the maximum torque by use of hand-held screw driver, and then torque value was measured with torque value was measured with torque driver(Tohnichi torque driver, model 20 FTD, Tohnichi MFG, Co., LTD., Tokyo, Japan). Abutment/superstructure complex of each implant system was titghtened to each torque of 10 N-cm, 20 N-cm and 30 N-cm, and then the dynamic load(vertical & diagonal load) was applied to the abutment / superstructure complex. The gap between abutment/superstrure in each implant system was measured with 3-dimensional measuring microscope(model No. 850, Germany). The results were as follow : 1. Torque values according to the individual subjects showed wide range. 2. Torque values according to sex showed statistical significant difference. Those are as follows : in case of male, $9.38{\pm}2.93$ N-cm ; incase of female, $7.80{\pm}2.25$ N-cm. 3. Torque values according t implant systems showed statistical significant difference. Those are as follows : in ase of Branemark implant system, $6.54{\pm}1.54$ N-cm : in ase of Steri-Oss implant system, $10.1{\pm}2.88$ N-cm ; in case of IMZ implant system, $9.18{\pm}2.17$ N-cm. 4. The more torque value of tightening screw was increased, the less the gap was after the vertical and diagonal loading. 5. The gap after the diagonal loading was greater than that after the vertical loading. 6. The magnitude of gap between abutment/superstructure in order of IMZ, Steri-Oss, Branemark implant system after the verical and diagonal loading. 7. The gap under the diagonal loading after applying 30 N-cm torque showed no statistical significant difference in cases of the Branemark system and the Steri-Oss implant system but it showed significant different in case of the IMZ implant system.
Journal of the korean academy of Pediatric Dentistry
/
v.39
no.3
/
pp.233-241
/
2012
Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. The aim of this study was to evaluate the effect of PDT on Streptococcus mutans in planktonic conditions, previously treated with different photosensitive concentrations of erythrosine, using halogen and LED curing unit as a light source. And we compared the effects of PDT on six strains of S. mutans isolated from oral cavity and reference strain. As a result, S. mutans was susceptible to the combination of hand held photopolymerizer (HHP) and erythrosine. The higher concentration of erythrosine in the presence of light irradiation induced greater effects in reduction of viability of S. mutans. Isolated S. mutans showed a significant reduction in bacterial counts of the groups submitted to PDT compared to the control groups. And they appeared to be similar or slightly lower antimicrobial effect compared with reference strain. However, the difference was not significant (p < 0.05). In conclusion, PDT using erythrosine as a photosensitizing agent and HHP as a light source could be an efficient option for diseases caused by S. mutans.
An experiment was conducted to assess the effects of dietary 3,5,3'-triiodo-L-thyronine ($T_3$) at 0, 10, 20, 50, 100 ppm on growth and survival rate in juvenile black seabream held at $27.9{\pm}1.1^{\circ}C$ for 50 days. Fish were fed the $T_{3}$ experimental diet for 4() days by hand to satiation in $2{\~}4$ times per day. After 50 days period, food intake rate (${\%}$), feed efficiency (${\%}$), survival rate (${\%}$), growth of weight and length (specific growth rates), and condition factor were measured. Food intake rate was inversely related to the dietary $T_{3}$ level. But feed efficiency was not changed by $T_{3}$ level. $T_{3}$ slightly improved survival rate of larvae. Survival rate of larvae from 100 ppm was significantly higher than that of fish from control. Dietary $T_{3}$ influenced growth in length and weight. Growth of black seabream fed a diet containing 10 ppm of $T_{3}$ was significantly higher than that of fish fed control. However 100 ppm of $T_{3}$ induced the inhibition for length and weight growth. The condition factor was inversely related to the dietary $T_{3}$ content.
From the economic point of view the fishing port is the complex of installations on land, organized to serve the fishing fleet and its cargo, and is the main link in the production chain of all components of the fishing industry, with the aim of achieving the planned targets with the minimum cost. Fishing port investment decisions have had significant impact on the development aims of Korean fisheries. Fishing port investments in Korea are made mostly by public or semipublic port authorities. Such investments should be judged not purely on the basis of financial profitability but rather on the extent to which they serve the development aims of the fishing industry. This makes the economic appraisal process more complex and presents certain problems in correctly quantifying the economic costs and benefits of the fishing port projects. This study concentrates more on the theoretical economic appraisal models than on the purely financial aspects of fishing port investments and points out the difference between the two approaches. In the result, there is clearly an element of judgment as to whether or not a shadow price needs to be used in estimating economic benefits and costs. From this viewpoint, some attempts are made to provide definitions of the possible economic benefits and costs, and methods for estimating and evaluating them in Part III and IV. Especially queueing theory is applied in the calculation of economic benefits. When a project is contemplated and analysis shows it to Lave a positive NPV, one question that arises is whether it should be implemented now or delayed. In this paper, the first year rate of return method is regarded as a more concise way of solving the timing of investment, At the end of Part IV, risk analysis of fishing port investments is considered. It can be handled in a number of ways, ranging from informal judgment to complex statistical analyses involving large-scale computer models, This paper recommends that evaluators of fishing port investments use the sensitivity analysis indicating exactly how much NPV will change in response to a given change in an input variable, other things held constant. Decisions regarding the amount of capacity to provide must be made in fishing port investments. Providing too much service would involve excessive capital costs. On the other hand, not providing enough service capacity would cause the waiting line of fishing vessels to become excessively long at times. Therefore, in Part V, the optimal number of berths and berth productivity in fishing port are defined as follows: Minimize E(TC) = E(WC)+E(SC) The minimum of this function is the solution and that is the optimal number of berth and berth productivity in fishing port.
Purpose: Lymphoscintigraphy and sentinel node biopsy has become a standard method for detection of axillary lymph node metastasis in breast cancer patients, but the standard radiopharmaceutical was not prepared. About detection of axillary lymph node metastasis by lymphoscintigraphy and sentinel node biopsy in breast cancer patient, we compared the results of Tc-99m Tin-colloid and Tc-99m Phytate by subareolar injection. Materials and Methods: This study included 382 breast cancer patients who were performed operation during 2001-2008. Three hundred forty nine patients was injected 0.8ml of Tc-99m Tin-colloid (37-185 MBq) by subareolar injection. Thirty three patients was injected 0.8ml of Tc-99m Phytate (37-185 MBq). Lymphoscintigraphy was performed in supine position and sentinel node localization was performed by hand-held gamma probe in operation. Result: Among 349 patients by Tc-99m Tin-colloid, 312 cases (89.4%) localized the sentinel node by lymphoscintigraphy, 304 cases (87.1%) localized by gamma probe. Among 33 patients by Tc-99m Phytate, 32 cases (97.0%) localized by lymphoscintigraphy, 33 cases (100%) localized by gamma probe. Detection rate by lymphoscintigraphy and gamma probe was superior for Tc-99m Phytate compared to that with Tc-99m Tin-colloid, with a statistically significant difference. (p<0.05, p<0.05) Conclusion: Tc-99m Phytate is a better choice for localization of sentinel node than Tc-99m Tin-colloid in breast cancer patients.
Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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v.17
no.1
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pp.28-37
/
2006
Purpose: Evaluation of vocal cord vibration is very important in cases of voice disorders. There are several equipments for examining the vocal fold vibration such as laryngeal stroboscope, ultra high-speed digital imaging system, and videokymograph. Among these, laryngeal stroboscope is the most popular equipment because of easy to examine the laryngeal pathology. However, current laryngo-stroboscopes are too bulky to move and relatively expensive. The purpose of this research is to develope a portable laryngeal stroboscope of equivalent performance with the current equipments. Methods and Materials: Recently developed high luminescent white LEDs(light emitting diodes) are placed at the head of the endoscope as light sources for the CCD image sensor which is also placed at the head with imaging lens. This arrangement eliminates the bulky light source like expensive halogen or xenon lamps as well as the optical light guiding cables. The LEDs are controlled to flash in phase with the voice frequency of the examinee. The CCD captures these strobo images and converts them into video signals for examinations. Results: There was no functional differences between preexisting stroboscope and the newly developed stroboscope of this study. LED light sources and microprocessor based control circuits of the stroboscope enabled the development of flicker-less, hand-held, portable and battery-operating stroboscope. Conclusion: The developed stroboscope is cost-effective, small-sized, easy to use and very easy desirable to bring and to use in any place.
The goal of medicine is to contribute to promoting national health by preventing diseases and providing treatment. The scope of modern medicine isn't merely confined to disease testing, treatment and prevention in accordance to that, and making experiments by using the human body is widespread. The advance in modern medicine has made a great contribution to valuing human dignity and actualizing a manly life, but there is a problem that has still nagged modern medicine: treatment and healing for terminal patients including cancer patients. In advanced countries, pain care and hospice medicine are already universal. Offering a helping hand for terminal patients to lead a less painful and more manly life from diverse angles instead of merely focusing on treatment is called the very hospice medicine. That is a comprehensive package of medical services to take care of death-facing terminal patients and their families with affection. That is providing physical, mental and social support for the patients to pass away in peace after living a dignified and decent life, and that is comforting their bereaved families. The National Hospice Organization of the United States provides terminal patients and their families with sustained hospital care and home care in a move to lend assistance to them. In our country, however, tertiary medical institutions simply provide medical care for terminal patients to extend their lives, and there are few institutional efforts to help them. Hospice medicine is offered mostly in our country by non- professionals including doctors, nurses, social workers, pastors or physical therapists. Terminal patients' needs cannot be satisfied in the same manner as those of other patients, and it's needed to take a different approach to their treatment as well. Nevertheless, the focus of medical care is still placed on treatment only, which should be taken seriously. Ministry for Health, Welfare & Family Affairs and Health Insurance Review & Assessment Service held a public hearing on May 21, 2008, on the cost of hospice care, quality control and demonstration project to gather extensive opinions from the academic community, experts and consumer groups to draw up plans about manpower supply, facilities and demonstration project, but the institutions are not going to work on hospice education, securement of facilities and relevant legislation. In 2002, Ministry for Health, Welfare & Family Affairs made an official announcement to introduce a hospice nurse system to nurture nurse specialists in this area. That ministry legislated for the qualifications of advanced nurse practitioner and a hospice nurse system(Article 24 and 2 in Enforcement Regulations for the Medical Law), but few specific plans are under way to carry out the regulations. It's well known that the medical law defines a nurse as a professional health care worker, and there is a move to draw a line between the responsibilities of doctors and those of nurses in association with medical errors. Specifically, the roles of professional hospice are increasingly expected to be accentuated in conjunction with treatment for terminal patients, and it seems that delving into possible problems with the job performance of nurses and coming up with workable countermeasures are what scholars of conscience should do in an effort to contribute to the development of medicine and the realization of a dignified and manly life.
Neo-Confucianism(性理學) which provided an ideological base to found Chosun Dynasty which substituted for Koryu Dynasty, presented In-Cheong(仁政) as ideal statecraft. In-Cheong(仁政) is realizing spirit of In(仁) which means a forever creating power(生生之心), for that reason it was a natural result that the ruling class of Chosun Dynasty had interest in medical science. Therefore they remarked 'In-Cheong(仁政) has achieved' when medical books were published, also remarked Hwal-In-Seo(活人署) as an institute of realizing Wang-Cheong(王政) while Hwal-In-Seo(活人署) was placed in very low civil service grade, although the ruling class classified medical science as a Chap-Hak(雜學) which means not essential but necessary knowledge, and ranked it much lower than Confucianism. While had improved medical service system of Korea Dynasty, Chosun Dynasty had special interest in local medicine: expanding provincal medical centers, educating a medical student(醫生) in a medical school who was core human power in local medicine, etc. Nevertheless the local medicine was still depressed. The reasons are ; not providing enough medical center, not much fund to run each center and mobilizing a medical student(醫生) for miscellaneous labor. Depressed local medicine had changed when 士族 came to have an interest in medical science. 士族 had read a lots of medical books from the early Chosun Dynasty. 16th century they even wrote some books on medicine by themselves based on their experience as a provincial governor. On the other hand Yi-Mun-Geon(李文楗) who wrote Muk-Jae Diary belongs to the latter. He did not use the art of acupucture. He was a civil official in Seoul, so he could get a lots of books and enough medical stuffs. After a while. he was exiled in Seong-Ju(星州) and took part in local medicine there. The local medicine was depressed in Seong-Ju(星州) at that time. Yi-Mun-Geon(李文楗) was a kind of medical consultant as well as a local doctor. Such medical doings by Sa-Jok(士族) may be a moment that provide power to local Sa-Jok(士族). Sa-Jok(士族) themselves were enthusiastic in treating their sick slaves because the slaves were financial foundation of Sa-Jok(士族). After 17th century, however, the relative importance which Sa-Jok(士族) in the country had held in 16th century had decreased gradually while professional doctors bad increased.
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