• The korean journal of orthodontics
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• v.35 no.4 s.111
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• pp.286-294
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• 2005

The purpose of this study was to evaluate the efficacy of an electric toothbrush, with a specially designed orthodontic brush head, compared to a manual toothbrush on the periodontal health of patients with fixed orthodontic appliances Forty patients were randomly divided into two groups. the electric and the manual toothbrush groups, 1 month after attachment of fixed orthodontic appliances. Periodontal status was measured using a plaque index, a gingival index. a bleeding index, a pocket depth and a relative attachment loss, at baseline and after 3 months. 6 months, 9 mouths. and 12 mouths. The Braun Oral-B Plak Control with Ortho OD 15-1 brush head was used as the electric toothbrush while the Butler G.U.M 124 was given as the manual toothbrush. In the manual toothbrush group, the giugival and bleeding indices showed no statistically significant differences, but the plaque index was significantly decreased (P<0.001) and pocket depth as well as relative attachment loss were significantly increased (p<0.01). In the electric toothbrush group. the bleeding index, pocket depth and relative attachment loss showed no statistically significant differences. but the plaque and gingival indices were significantly decreased (p<0.001). In the case of the plaque. giugival and bleeding indices, there were no statistically significant differences between the electric and the manual toothbrush groups. On the contrary, in the case of pocket depth and relative attachment loss, there were statistically significant differences between the electric and the manual toothbrush groups: an increase in the manual toothbrush groups unlike the electric toothbrush group which kept the same state (P<0.05) These findings suggest that an electric toothbrush is useful for orthodontic patients with fixed appliances.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.17.1-17
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• 1982

In 1965, Rosenberg reported that platinum compounds not only inhibit growth and cell division of E. coli but also has anti-tumor activity. Since then, through animal and clinical experiments by Welsch(1971), Speer(1972), Rossof(1972), Hill(1974), and Wittes(1975), it was proved that Cis-platinum has excellent supressive effects on malignant tumor, especially on head and neck cancer. Accordingly, Cis-platinum is now widely used, sometimes without any other durg, or sometimes with Bleomycin and Methotrexate etc. Inspite of the strong anticancer effect, the use of Cis-platinum is quite often discouraged because of the reports that Cis-platinum causes auditory impairment at high frequencies above the speech range due to inner ear damage and irreversible change in the renal tubules. Since Kohonen et al(1965), Standnicki et al(1974) reported that Cisplatinum has toxic effects at the basal turn of the cochlea using guinea pig, many studies on ototoxicity after infusion of Cis-platinum have been carried out using animals. But the studies on ototoxicity in human beings can hardly be found except in reports by Piel et al(1974) and Hong et al (1979). So the authors did a study which tried to clarify the ototoxic effect by comparing the hearing level after infusion of Cis-plastinum with the hearing level before infusion of Cis-plastinum in 30 patients who was treated with Cis-platinum and admitted to the dept. of otolaryngology of Yonsei University Hospital during 2 years and a half from July. 1979 to March. 1982 and the following results were obtained. 1) The results of auditory evaluation, using the pure tone average, hearing loss of 4kHz and 8kHz, Speech Reception Threshold, PB score, SISI showed that the difference of dosage does not change the hearing level after infusion of Cis-platinum and before infusion of Cis-platinum. 2) Cis-platinum had no effect on the hearing level of patients with conductive hearing loss, or with sensorineural hearing loss, as well as with normal hearing level. 3) The infusion of Cis-platinum did not cause any change in creatinine clearance, creatinine, uric acid, but only one case showed that Cis-platinum caused severe nephrotoxicity. 4) The infusion of Cis-plastinum did not cause any change in hemoglobin, leukocyte count, platelet count and there was no correlation with the amount of infusion. 5) To see the side effect of hydration practiced with the infusion of Cis-platinum, the electrolytes, particularly the K level in the serum was measured. But the results did not show any change. 6) Judging from the results of this study mentioned above, ototoxicity caused by infusion of Cis-platinum can be prevented by sufficient hydration. Also the results might say that the appropriate method of infusion of Cis-platinum might be effective in the patients with head and neck cancer who had sensorineural hearing loss for whom the infusion of Cis-platinum has been absolutely cotraindicated.

• Agricultural and Biosystems Engineering
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• v.4 no.2
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• pp.58-65
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• 2003

An understanding of the cooling requirements of horticultural commodities begins with adequate knowledge of their biological responses. All fresh horticultural products are living organisms, carrying on the many biological processes that are essential to the maintenance of life. The pre-cooling is essential technique for the construction of cold chain system, which is necessary to maintain marketing quality of fresh produces during the transportation and distribution. The purpose of this study is to develop the pressure cooling tunnel using conveyer for the reduction of labor and improvement of pre-cooling efficiency. Performance of developed facility was tested for the strawberries, tomatoes and Chinese cabbages. Cooling ratio as a result of pre-cooling efficiency was 1.57, 1.56 and 1.32 for strawberries, tomatoes, and Chinese cabbages respectively. Cooling ratio decreased with increasing the distance of heat conduction from surface to center. The cooling ratio of Chinese cabbages was lower than that of fruit because of its head and leaf. In aspect of cooling uniformity, there was no significant difference of final temperature among inlet, outlet and middle layers of cold air in fresh produces. After pre-cooling treatment, quality changes were measured for the weight loss, Vit. C content, and titratable acidity. The quality of pre-cooling treatment was better than that of non-treatment and was kept on well during long-term storage.

• Horticultural Science & Technology
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• v.16 no.1
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• pp.25-26
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• 1998

Nutrient supplying by a metering pump often produces the inaccuracy in the rate of inflow than expected. In this study, we developed the transpiration estimation system using the metering pump to measure the continuous supplying rate as well as to estimate the accurate transpiration rate. The system showed the stable characteristics by eliminating the fluctuations in the head loss of nutrient tank. The direct proportionality between the supplying time and the supplied nutrient solution was obtained. The exact correlation between the integrated solar radiation and the transpiration rate using the system was calculated, and correlation coefficients between the two factors were 0.98 in the NFT system and 0.92 in the aggregate system. This results suggest that the integrated solar radiation was an important factor to directly decide the supplying volume of nutrient solution in soilless culture system. The deveolped system using the metering pump in the study was able to control the supply of the nutrient solution to the crops adjusting to the variation of solar radiation.

• 보존과학연구
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• s.26
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• pp.141-164
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• 2005

Most of the stone cultural properties is exposed to the weathering factor(rain, windetc.), so the shelter is constructed for reduction of its direct effect. But the shelter is indicated some problems that inharmoniousness of the surroundings, in section disturbance for insufficiency of light, the loss about the value of cultural properties and so on. So we have investigated on environmental condition (temperature, relative humidity, wind etc.) at the Standing Stone Buddhist Triad in Bae-ri, Gyeongju and Rock-carved Triad Buddha in Seosan because check the effect of the shelter. As the result, the Standing Stone Buddhist Triad in Bae-ri, Gyeongju is located a pine wood and a lot of bamboo grow naturally in nearing. Environmental difference on inside and outside of the shelter is not found because opened on all sides. But there is so dim for the direction of the sunlight that can't see the Standing Stone Buddhist. The base rock of Rock-carved Triad Buddha in Seosan well develop with crack and break, and the vegetation(trees, moss, lichen etc.) grow naturally in surroundings. Environmental difference on inside and outside of the shelter is found because closed on all sides and opened the front gate only inspection time. Inside of the shelter was too calm(air-velocity not detected) and humid(over 75%RH). Also the surface is occurred the dew(at 2-4 pm) and the efflorescence for effect of the water(rain, dew etc.). Besides the head of the central Buddhist is so dangerous for crack.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.164-170
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• 1992

Haemorrhagic ulcer in cultured snakehead(Chann0 argus) is widespread in Korea during the summer season. Round haemorrhagic ulcers as the main symptom of this epizootic disease can be found on the skin of the head. body, as well as fins of this fish. This study was conducted to investigate the pathology of this disease. First. Aeromonas veronii. the dominant species. was isolated from diseased snakeheads. Then this bacterium was injected into healthy snakeheads hypodermically. Such injection was found to induce haemorrhagic ulcers very similar to those observed in naturally infected fish. One or two days afier the injection, a red spot developed around the injection site. and grew bigger to from a red area. This enlarged area then developed into haemorrhagic ulcer, accompanied by substantial skin loss. Within five days. muscle necrosis proceeded to the extent that a perforation was made between the injection site and the opposite side. The fifty per cent lethal dosage was found to be $1\times10^{5}$CFU/0.25 ml by intraperitoneal injection. The results of this experiment lead us to conclude that Arromonas veronii is a major bacterium which causes haemorragic ulcer in cultured snakcheads.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.1059-1065
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• 2010

An analysis was conducted to predict the hydraulic performance of a reactor coolant pump (RCP) of SMART at the off-design as well as design points. In order to reduce the analysis time efficiently, a single passage containing an impeller and a diffuser was considered as the computational domain. A stage scheme was used to perform a circumferential averaging of the flux on the impeller-diffuser interface. The pressure difference between the inlet and outlet of the pump was determined and was used to compute the head, efficiency, and break horse power (BHP) of a scaled-down model under conditions of steady-state incompressible flow. The predicted curves of the hydraulic performance of an RCP were similar to the typical characteristic curves of a conventional mixed-flow pump. The complex internal fluid flow of a pump, including the internal recirculation loss due to reverse flow, was observed at a low flow rate.

• Tunnel and Underground Space
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• v.25 no.6
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• pp.543-555
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• 2015

At present, local limestone mines with large opening employ auxiliary fans for workplace ventilation which have been used in coal mines with much smaller airways. Considering the low static pressure loss in the large-opening mines, high pressure auxiliary fans face serious economical limitations mainly due to their excessive capacity. The optimal fan selected for the ventilation in large-opening working places should supply air quantity enough for maintaining safe environment and keep its operating cost as low as possible. This study focuses on the development of a low pressure auxiliary fan designed to have smaller range of the static head but to have more potential for higher ventilation and energy efficiency. The flow characteristics of high and low pressure auxiliary fans were theoretical as well as experimentally investigated to assess the ventilation efficiency in term of environmental and economical aspects. Moreover, the low pressure fan was tested in two limestone mine sites with small and large cross-sectional areas for evaluating its ventilation efficiency. Results from this study can be applied to improve the economy and efficiency of auxiliary fan for ensuring better air quality and work environment management.

• Journal of Korean Society on Water Environment
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• v.33 no.5
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• pp.572-579
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• 2017

Increased impervious surface caused by rapid urbanization serves to produce the discharge of non-point source pollutants such as total suspended solid (TSS). There exist various methods of removing TSS, including a filtration process using granular media (a well-known method to be practically used after the consideration of removal efficiency, clogging, and backwashing efficiency). To determine the TSS removal capability of the filter, we initially performed lab-scale experiments which assessed flow rates, influent concentrations, permeability co-efficients, the particular shapes of suspended solids and potential clogging, and also evaluated TSS removal efficiency when applied to filtration facility in a pilot-scale. In low filtration flux condition, the removal efficiency of suspended solids was more than 95 %, while decreased to 83% in high filtration flux. Regarding the clogging aspect of the experiment, total cumulative solids were loaded up to $19.15kg/m^2$, and TSS removal efficiency was noted to commence to decrease when the loaded solids exceeded $9.0kg/m^2$. It was also noted, however, that superior efficiency was maintained for six hours. In addition, for pilot-scale experiment, the removal efficiency was still high enough (83.4 %) for the solid concentration of 140 ~ 343 mg SS/L and after backwashing, head loss was recovered to 92 ~ 95 % during two hour filtration. With these results, It was confirmed that lifetime of the filter applied to the test was prolonged due to the high treatment efficiency and good backwashing efficiency for the cumulative solids load.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.13 no.1
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• pp.67-72
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• 2007

Anatomy: The rotator cuff comprises four muscles-the subscapularis, the supraspinatus, the infraspinatus and the teres minor-and their musculotendinous attachments. The subscapularis muscle is innervated by the subscapular nerve and originates on the scapula. It inserts on the lesser tuberosity of the humerus. The supraspinatus and infraspinatus are both innervated by the suprascapular nerve, originate in the scapula and insert on the greater tuberosity. The teres minor is innervated by the axillary nerve, originates on the scapula and inserts on the greater tuberosity. The subacromial space lies underneath the acromion, the coracoid process, the acromioclavicular joint and the coracoacromial ligament. A bursa in the subacromial space provides lubrication for the rotator cuff. Etiology: The space between the undersurface of the acromion and the superior aspect of the humeral head is called the impingement interval. This space is normally narrow and is maximally narrow when the arm is abducted. Any condition that further narrows this space can cause impingement. Impingement can result from extrinsic compression or from loss of competency of the rotator cuff. Syndrome: Neer divided impingement syndrome into three stages. Stage I involves edema and/or hemorrhage. This stage generally occurs in patients less than 25 years of age and is frequently associated with an overuse injury. Generally, at this stage the syndrome is reversible. Stage II is more advanced and tends to occur in patients 25 to 40 years of age. The pathologic changes that are now evident show fibrosis as well as irreversible tendon changes. Stage III generally occurs in patients over 50 years of age and frequently involves a tendon rupture or tear. Stage III is largely a process of attrition and the culmination of fibrosis and tendinosis that have been present for many years. Treatment: In patients with stage I impingement, conservative treatment is often sufficient. Conservative treatment involves resting and stopping the offending activity. It may also involve prolonged physical therapy. Sport and job modifications may be beneficial. Nonsteroidal anti - inflammatory drugs(NSAIDS) and ice treatments can relieve pain. Ice packs applied for 20 minutes three times a day may help. A sling is never used, because adhesive capsulitis can result from immobilization.