• Journal of Chest Surgery
• /
• v.29 no.11
• /
• pp.1232-1240
• /
• 1996

From January 1990 through June 1995, we operated on 121 patients who were suspected for pulmonary tuberculosis without definite final diagnosis. After operation the final pathologic diagnoses were as follows: 68 pulmonary tuberculosis in which 29 were tuberculoma, 23 lung cancer, 16 bronchiectasis, 6 aspergilloma, 2 lung abscess, 2 benign cyst and 4 others. In 121 cases, 81 were male and 40 were female and the peak age incidence was 4th decade in tuberculosis (39.7%) and 6th and 7th decade in lung cancer (69.6%). The diagnoses in 44 cases presented roentgenographically as pulmonary nodules were pulmonary tuberculosis(29 cases) and lung cancer(15 cases). Tuberculous nodules tended to be smaller in size with calcification and satellite lesions compared to carcinomas. Indications for operation were solitary nodules 44 cases (36.4%); destroyed lobe 31(25.6%); hemoptysis 25 (20.7%); cavitary lesion 11(9.1 %); bronchostenosis 3 (2.5%); destroyed lung 5(4.1 %) and destroyed lung with empyema 2(1.7%). We conclude that preoperatively suspected pulmonary tuberculosis should be distinguished from various pulmonary lesions such as carcinoma, bronchiectasis, aspergilloma, lung abscess and benign cyst. For the possibility of carcinoma, pulmonary nodules of size greater than 3cm, non-calcified, non satellite lesion, newly developed nodule even under the anti-tuberculous medication, negative PPD skin test with elevated CEA level are recommended for an early resectional surgery and follow-up and delayed surgery is recommended in cases such as pulmonary nodules less than 3 cm in size with calcification, satellite lesion, positive PPD skin reaction and elevated ESR, CRP, ALP levels.

• Journal of Wetlands Research
• /
• v.17 no.2
• /
• pp.146-154
• /
• 2015

Domestic railway industry has grown in numbers, scale of railway ndustrial and operation because was focused on an environmentally sustainable transportation. However, it is not enough to treat and prevent heavy metals which occur as the railway operation increases. The heavy metals occurred when the operating railway and it will be flow into water system with rainfall effluent during rainfall. will flow out along with the rainfall effluent when rainfall comes. In case of a railway bridge, In particular, heavy metals were flow into the water system without any treatment from railway bridges where located nearby rivers and lakes. So, rainfall effluent from railway facilities was occurred pollution of water system. For the prevent of heavy metal runoff during rainfall, the adsorptivity of material in railway roadbed is important.In this study, adsorptivity of gravel which is main gravel and blast-furnace slag were conducted adsorption test and deducted Freundlich's and Langmuir's isothermal adsorption equations. Safety as railway subbase course material was evaluated using modeling. As a result, absorption amount of slag, Cd and Cu, was shown higher than gravel and Pb along with Zn showed higher absorption amount of gravel. However, absorption amount of slag was shown higher than gravel used as railway subbase course material as time passes by. Absorption features had more suitable determination coefficient of heavy metals in warm absorption type such as Langnmuir compared to warm absorption type like Freundlich. To add, they showed less transformation by about 10% compared to gravel in safety evaluation through modeling. This is a railway subbase course material that prevents water outflow of heavy metal thus we can know slag is needed to be used.

• Journal of Wetlands Research
• /
• v.12 no.2
• /
• pp.25-33
• /
• 2010

Three plans(induction of water flow, supply of oxygen into water, control of fish causing resuspension of solids) proposed to improve the pollutant removal efficiency of Sihwa Constructed Wetland(CW) were estimated by considering the their efficiency and application to the wetland. After construction of facility for induction of water flow in lower part(W 122m${\times}$L 103m) of the wetland, the mean removal efficiencies of BOD, SS, TN and TP were in range of 12.8~37.4% and BOD was showing the highest efficiency. This result indicates that water flows is one of very important factors in the pollutant removal of wetland, especially near the outlet of a large scale wetland such as Sihwa CW. Dissolved oxygen(DO) concentrations after operation of two oxygen supply systems such as Air Bubble Diffuser and Surface Aeration System increased 15.5% and 27.2%, respectively. For maintaining effective DO concentration in Sihwa CW, the operation of oxygen supply system may be desirable during midnight to dawn in the location in which DO concentration is not enough, for instance less than 2 mg/L in CW. In experiments of the fish removal from Sihwa CW, the mean turbidity was lower in test site(6.2 NTU) than control site(10.6). The removal efficiency of thurbidity by th fish removal from the wetland was 41.5%. Therefore, a relevant fish management through a periodical monitoring of fish and turbidity is needed.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.4
• /
• pp.504-510
• /
• 2017

This paper presents an AC-DC power module design and evaluates its efficiency and reliability when used for electronics appliances. This power module consists of a PWM control IC, power MOSFETs, a transformer and several passive devices. The module was tested at an input voltage of 220V (RMS) (frequency 60 Hz). A test was conducted in order to evaluate the operation and power efficiency of the module, as well as the reliability of its protection functions, such as its over-current protection (OVP), overvoltage protection (OVP) and electromagnetic interference (EMI) properties. Especially, we evaluated the thermal shut-down protection (TSP) function in order to assure the operation of the module under high temperature conditions. The efficiency and reliability measurement results showed that at an output voltage of 5 V, the module had a ripple voltage of 200 mV, power efficiency of 73 % and maximum temperature of $80^{\circ}C$ and it had the ability to withstand a stimulus of high input voltage of 4.2 kV during 60 seconds.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.7
• /
• pp.940-944
• /
• 2006

The propose of this study was to evaluate the microbiological hazards of the customers' hands in university foodservice operation. A total of 190 customers' hands were sampled to test about aerobie plate counts, coliforms, E. coli and Staphylococcus aureus. The average number of aerobic plate counts was 3.11 log CFU/hand Ifrom 0.70 to 6.47 log CFU/hand) and that of coliform counts was 1.06 log CFU/hand (from not detected to 5.04 log CFU/hand). The mean level of aerobic plate counts (t=9.87, p<0.001) and coliforms (t=7.91, p<0.05) was significantly different by gender. E. coli was not detected, but Staphylococcus aureus was detected in 39 (20.5%) of 190 samples. The average of hand-washing frequency was 6.46 time per day. By the hand-washing frequency, the mean level of aerobic plate counts was significantly different (F=527, p<0.001), but coliforms was not significantly different. This study shows that it is needs to be given attention to hygiene handlers but also for customers in foodservice operations.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.19 no.2
• /
• pp.110-126
• /
• 2021

Purpose: The purpose of this study is to find out the current status of toxicology laboratory operated by six locations nationwide and to investigate the satisfaction of emergency medical professionals who working at local and regional emergency medical centers. Methods: This survey was conducted prospective. It was conducted on 665 emergency medical professionals working at regional and regional emergency medical centers across the South Korea. Among them, the analysis was conducted with data that 510 emergency medical professionals who respond to this survey. The questionnaire was conducted on an online basis for a month. To ensure statistical significance, consider a dropout rate of 10% based on a minimum response recovery rate of 70%. 506 people were selected for the survey. Results: According to a survey on the status of addiction analysis room usage, the average monthly usage of addiction test rooms among respondents were 406 cases.71.0 cases (17.4%) of toxicology laboratory in Seoul and 71 cases (17.4%) in Gwangju. 32 cases (7.8%), 118 cases (29.0%) requested by toxicology laboratory in Busan, and the toxicology laboratory in Daegu. Eighty two cases (20.1%), Daejeon area 25 cases (6.1%), Wonju area toxicology laboratory was 78 (19.6%). According to a survey on the satisfaction of the addiction analysis room,Seoul (4.9±2.71) and Gwangju (4.8±2.52) showed high satisfaction. Conclusion: Due to the limited operation time of the four addiction analysis rooms currently in operation, the satisfaction level of addiction analysis by emergency medical professionals in the area is low due to the delay until the result is notified.

• Journal of Korean Neurosurgical Society
• /
• v.64 no.6
• /
• pp.933-943
• /
• 2021

Objective : Percutaneous pedicle screw (PPS) fixation is a needle based procedure that requires fluoroscopic image guidance. Consequently, radiation exposure is inevitable for patients, surgeons, and operation room staff. We hypothesize that reducing the production of radiation emission will result in reduced radiation exposure for everyone in the operation room. Research was performed to evaluate reduction of radiation exposure by modifying imaging manner and mode of radiation source. Methods : A total of 170 patients (680 screws) who underwent fusion surgery with PPS fixation from September 2019 to March 2020 were analyzed in this study. Personal dosimeters (Polimaster Ltd.) were worn at the collar outside a lead apron to measure radiation exposure. Patients were assigned to four groups based on imaging manner of fluoroscopy and radiation modification (pulse mode with reduced dose) : continuous use without radiation modification (group 1, n=34), intermittent use without radiation modification (group 2, n=54), continuous use with radiation modification (group 3, n=26), and intermittent use with radiation modification (group 4, n=56). Post hoc Tukey Honest significant difference test was used for individual comparisons of radiation exposure/screw and fluoroscopic time/screw. Results : The average radiation exposure/screw was 71.45±45.75 µSv/screw for group 1, 18.77±11.51 µSv/screw for group 2, 19.58±7.00 µSv/screw for group 3, and 4.26±2.89 µSv/screw for group 4. By changing imaging manner from continuous multiple shot to intermittent single shot, 73.7% radiation reduction was achieved in the no radiation modification groups (groups 1, 2), and 78.2% radiation reduction was achieved in the radiation modification groups (groups 3, 4). Radiation source modification from continuous mode with standard dose to pulse mode with reduced dose resulted in 72.6% radiation reduction in continuous imaging groups (groups 1, 3) and 77.3% radiation reduction in intermittent imaging groups (groups 2, 4). The average radiation exposure/screw was reduced 94.1% by changing imaging manner and modifying radiation source from continuous imaging with standard fluoroscopy setting (group 1) to intermittent imaging with modified fluoroscopy setting (group 4). A total of 680 screws were reviewed postoperatively, and 99.3% (675) were evaluated as pedicle breach grade 0 (<2 mm). Conclusion : The average radiation exposure/screw for a spinal surgeon can be reduced 94.1% by changing imaging manner and modifying radiation source from real-time imaging with standard dose to intermittent imaging with modified dose. These modifications can be instantly applied to any procedure using fluoroscopic guidance and may reduce the overall radiation exposure of spine surgeons.

• Journal of Digital Convergence
• /
• v.19 no.5
• /
• pp.263-268
• /
• 2021

The purpose of this study was to propose a model which is suitable for the actual delivery system by designing a fetal delivery hospital operation management and fetal health classification model. The number of deaths during childbirth is similar to the number of maternal mortality rate of 295,000 as of 2017. Among those numbers, 94% of deaths are preventable in most cases. Therefore, in this paper, we proposed a model that predicts the health condition of the fetus using data like heart rate of fetuses, fetal movements, uterine contractions, etc. that are extracted from the Cardiotocograms(CTG) test using a random forest. If the redundancy of the data is unbalanced, This proposed model guarantees a stable management of the fetal delivery health management system. To secure the accuracy of the fetal delivery health management system, we remove the outlier which embedded in the system, by setting thresholds for the upper and lower standard deviations. In addition, as the proportion of the sequence class uses the health status of fetus, a small number of classes were replicated by data-resampling to balance the classes. We had the 4~5% improvement and as the result we reached the accuracy of 97.75%. It is expected that the developed model will contribute to prevent death and effective fetal health management, also disease prevention by predicting and managing the fetus'deaths and diseases accurately in advance.

• Journal of the Korean Solar Energy Society
• /
• v.39 no.1
• /
• pp.59-66
• /
• 2019

BIPV or BAPV installation applied to building is increasing through public utility mandates enterprise. Solar PV energy generates only during the day, but if it is operated in convergence with ESS, which stores electrical energy, it can restrain the fossil energy used in buildings throughout the day. A solution is to converge with PV system and ESS. However, PV systems and ESS connected to the power grid in parallel can cause problems of electrical stability. A study was conducted on the case of failure to detect islanding operation under the parallel operation of PV generation and ESS that are connected in parallel to power grid. Experiments conducted various non-islanding detections under the operating conditions. In the experiment results, when one PCS - PV inverter or ESS inverter - was operating under the islanding condition, it stopped working within 0.5 seconds of the Korean grid standard. However, when both of PV inverter and ESS inverter were operating at the same time under the islanding situation, the anti-islanding algorithm did not operate normally and both inverters continuously supplied power to the connected RLC loads. islanding detection Algorithm developed by each inverter manufacturer has caused this phenomenon. Therefore, this paper presented a new test standard for islanding detection.

• Journal of IKEEE
• /
• v.23 no.2
• /
• pp.743-746
• /
• 2019

In this paper we proposed a new ocean radiation automatic monitoring system. The proposed system has the following characteristics: First, using NaI + PVT mixed detectors, the response speed is fast and precision analysis is possible. Second, the application of temperature compensation algorithm to scintillator-type sensors does not require additional cooling devices and enables stable operation in the changing ocean environment. Third, since cooling system is not needed, electricity consumption is low, and electricity can be supplied reliably by utilizing solar energy, which can be installed at the observation deck of ocean environment. Fourth, using GPS and wireless communications, accurate location information and real-time data transmission function for measurement areas enables immediate warning response in the event of nuclear accidents such as those involving neighboring countries. The results tested by the authorized testing agency to assess the performance of the proposed system were measured in the range of $5{\mu}Sv/h$ to 15mSv/h, which is the highest level in the world, and the accuracy was determined to be ${\pm}8.1%$, making normal operation below the international standard ${\pm}15%$. The internal environmental grade (waterproof) was achieved, and the rate of variation was measured within 5% at operating temperature of $-20^{\circ}C$ to $50^{\circ}C$ and stability was verified. Since the measured value change rate was measured within 10% after the vibration test, it was confirmed that there will be no change in the measured value due to vibration in the ocean environment caused by waves.