• Journal of Korean Society of Health-System Pharmacists
• /
• v.35 no.4
• /
• pp.409-417
• /
• 2018

Background : Febrile neutropenia (FN) is one of the side effects in the patients treated with chemotherapy, and the patients who have FN generally need immediate treatment with extended-spectrum antibiotics and hospitalization. Pegfilgrastim and pegteograstim, which are used for the prevention of FN as a granulocyte-colony stimulating factor (G-CSF), have been granted insurance coverage in the Republic of Korea for certain breast cancer patients using doxorubicin and cyclophosphamide (AC) from September 2016. Methods : The data of the patients with breast cancer using AC regimen and G-CSF were collected retrospectively. This study involves cost-utility analysis of pegfilgrastim and pegteograstim. In this study, we constructed a simple decision tree model for short-term observation and calculated quality-adjusted life year (QALY) and the direct medical costs from the medical provider's perspective. Results : From September 2016 to May 2017, 15 patients were treated with pegfilgrastim and 15 patients were treated with pegteograstim. As a result of dividing the average cost by QALY for each treatment group, it was observed that pegfilgrastim and pegteograstim were consumed 24,923,384 won and 22,808,336 won per 1QALY, respectively. Consequently, incremental cost effectiveness ratio (ICER) showed 2,115,048 won more per pegfilgrastim than pegteograstim per 1QALY, and the cost per 1QALY of both the drugs was lower than 30,500,000 won; the Koreans were willing to pay this amount. Conclusions : This study suggests that pegfilgrastim and pegteograstim can be used to improve the quality of life of breast cancer patients undergoing AC therapy. Among the two drugs, pegteograstim seems to be more cost-effective. However, since this study was conducted as a retrospective observation method on a small scale, it is associated with many limitations. Therefore, a long-term prospective cohort study is needed to supplement the present findings.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.13 no.4
• /
• pp.152-159
• /
• 1999

This paper describes the rmtion characteristics of a particle in GIS under AC voltage. To measure the motion characteristics of the particle, a model gas chamber and parallel plain electrodes were designed and manufactured lift-off voltages of wire and spherical particles on the electrode were calculated and rreasured, and electric charge was calculated. By using a high speed carrera, the rmtion characteristics of various particles with aw}ied voltages, such as motion pattern, lift-off time, lift-off height, were analyzed 1be lift-off voltages were greatly affected by diarreters of wire and spherical particles. At voltage around lift-off voltage, the stand-up particle in vertical state rmved up and down between electrodes and the height of the lift-off particle was low. At voltage around breakdown voltage, the particle repeated vertical rotation a few times while they were being lifted off, and then, they were floating between the electrodes.trodes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.21 no.1
• /
• pp.85-89
• /
• 2008

An objective of this paper is to develop a partial discharge (PD) measurement device for monitoring gas insulated switches installed in power distribution system. A capacitive voltage probe was studied and designed to detect PD pulse without an electrical connection. The PD measurement device consists of the capacitive voltage probe attached outside of a bushing, a coupling network which attenuates AC voltage by 270 dB, and a low noise amplifier with the gain of 40 dB in ranges of 500 kHz${\sim}$20 MHz. The sensitivity of the prototype device calculated by a calibrator was 1.98 m V /pc. An application experiment was carried out in a 25.8 kV gas insulated switch and the peak pulse of 76.7 pC was detected. From the experimental results, it is expected that the PD measurement device can be applied to online monitoring system of gas insulated switches.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.31 no.4
• /
• pp.417-424
• /
• 2007

This paper reports fabrication and characterization of a pressure sensor using a pitch-based carbon fiber. Pitch-based carbon fibers have been shown to exhibit the piezoresistive effect, in which the electric resistance of the carbon fiber changes under mechanical deformation. The main structure of pressure sensors was built by performing backside etching on a SOI wafer and creating a suspended square membrane on the front side. An AC electric field which causes dielectrophoresis was used for the alignment and deposition of a carbon fiber across the microscale gap between two electrodes on the membrane. The fabricated pressure sensors were tested by applying static pressure to the membrane and measuring the resistance change of the carbon fiber. The resistance change of carbon fibers clearly shows linear response to the applied pressure and the calculated sensitivities of pressure sensors are $0.25{\sim}0.35 and 61.8 ${\Omega}/k{\Omega}{\cdot}bar$ for thicker and thinner membrane, respectively. All these observations demonstrated the possibilities of carbon fiber-based pressure sensors.

• International Journal of Safety
• /
• v.8 no.2
• /
• pp.9-14
• /
• 2009

This paper describes analysis of risk voltage for grounding electrode where earth leakage current is injected. To assess risk voltage of grounding electrode, the grounding simulator and CDEGS program were used to obtain measured data and theoretical results of this study. The grounding simulator was composed of a hemispherical water tank, AC power supply, a movable potentiometer, and test grounding electrodes. The shapes of grounding electrode model was ground rod. The potential rise was measured by grounding simulator, and the touch and step voltages were computed by CDEGS program. As a consequence, the potential rise of ground rod abruptly decreases with increasing the distance from the grounding electrode to the point to be tested. The touch voltage above the ground rod was low, but the step voltage was high. The measured results were compared with the computer calculated data and were known in good agreement.

• Journal of Environmental Health Sciences
• /
• v.40 no.1
• /
• pp.38-46
• /
• 2014

Objectives: This study was carried out in order to estimate atmospheric polycyclic aromatic hydrocarbon (PAH) concentrations and sources using pine needles as a passive air sampler (PAS) in urban (Pyeongtaek), semirural (Anseong) and rural (Jincheon) sites. Methods: One-year-old pine needles were collected for analysis of their PAH concentrations ($C_{p,n}g/g$ dry) at the end of December. PAHs concentrations in the ambient air ($C_a$, $ng/m^3$) were calculated with a $Log(C_p/C_a)-LogK_{oa}$ correlational equation. Results: PAHs concentrations in ambient air ($C_a$) were high, in the order of urban ($114.03ng/m^3$), semirural ($105.17ng/m^3$) and rural ($61.91ng/m^3$) sites. However, distributions of PAH isomer concentrations were very similar. PAHs of which molecular weight is smaller than 228.30 (AcPy, Acp, Flu, Phen, Ant, Flt, Pyr, BaA, Chry) made up most of the PAHs in the ambient air (96.6-98.5%). Conclusion: At urban, semirural and rural sites, it was concluded that the main source of PAHs in the ambient air ratio of each PAH isomer concentration was cars, especially diesel vehicles.

• Journal of Power Electronics
• /
• v.16 no.2
• /
• pp.654-665
• /
• 2016

The pumping of electric power from photovoltaic (PV) farms is normally carried out using transformers, which require heavy mounting structures and are thus costly, less efficient, and bulky. Therefore, transformerless schemes are developed for the injection of power into the grid. Compared with the H4 inverter topology, the H6 topology is a better choice for pumping PV power into the grid because of the reduced common mode current. This paper presents how the perturb and observe (P&O) algorithm for maximum power point tracking (MPPT) can be implemented in the H6 inverter topology along with the improved sinusoidal current injected to the grid at unity power factor with the average current mode control technique. On the basis of the P&O MPPT algorithm, a power reference for the present insolation level is first calculated. Maintaining this power reference and referring to the AC sine wave of bus bars, a sinusoidal current at unity power factor is injected to the grid. The proportional integral (PI) controller and fuzzy logic controller (FLC) are designed and implemented. The FLC outperforms the PI controller in terms of conversion efficiency and injected power quality. A simulation in the MATLAB/SIMULINK environment is carried out. An experimental prototype is built to validate the proposed idea. The dynamic and steady-state performances of the FLC controller are found to be better than those of the PI controller. The results are presented in this paper.

• KIEE International Transactions on Power Engineering
• /
• v.5A no.3
• /
• pp.214-220
• /
• 2005

In order to improve energy efficiency and solve power disturbances, power components measurement for both the supply and demand side of a power system must be implemented before appropriate action on the power problems can be taken. This paper presents a DSP (Digital Signal Processor)-based multi-channel (voltage 8-channel and current 10-channel) power measurement system that can simultaneously measure and analyze power components for both supply and demand. Voltage 8-channel and current 10-channel measurement is made through voltage and current sensors connected to the developed system, and power components such as reactive power, power factor and harmonics are calculated and measured by the DSP. The measured data are stored in a personal computer (PC) and a commercial program is then used for measurement data analysis and display. After voltage and current measurement accuracy revision using YOKOGAWA 2558, the developed system was tested using a programmable ac power source. The test results showed the accuracy of the developed system to be about 0.3 percent. Also, a simultaneous measurement field test of the developed system was implemented by application to the supply and demand side of the three-phase power system.

• International Journal of Internet, Broadcasting and Communication
• /
• v.14 no.2
• /
• pp.79-88
• /
• 2022

Recently, securing stable supply of fresh food is deemed as one of the important tasks. Accordingly, now the presence of cold chain along with the needs of a comfortable and healthy life is growing as the online market expands and the contactless industry grows, however, cold chain is being studied only in the aspect of ground and sea transportation. And, due to global warming and strengthening global environmental regulations, we believe that it is necessary to convert the existing road-centered logistics system into a railway-centered logistics system, a low-carbon transportation means. Therefore, in this paper we calculated the maximum energy required by the reefer container as a basic research necessary for constructing the low temperature distribution and cold chain based on the reefer container railway, and conducted a study on methods of supplying the reefer container power utilizing 1. tramline, 2. battery, 3. generator. The results of this paper can be utilized as a foundational study for building a cold chain based on a reefer container dedicated to freight trains in the future.

• Korean Journal of Materials Research
• /
• v.29 no.8
• /
• pp.463-468
• /
• 2019

The electrical and interfacial properties of $HfO_2/Al_2O_3$ and $Al_2O_3/HfO_2$ dielectrics on AlN/p-Ge interface prepared by thermal atomic layer deposition are investigated by capacitance-voltage(C-V) and current-voltage(I-V) measurements. In the C-V measurements, humps related to mid-gap states are observed when the ac frequency is below 100 kHz, revealing lower mid-gap states for the $HfO_2/Al_2O_3$ sample. Higher frequency dispersion in the inversion region is observed for the $Al_2O_3/HfO_2$ sample, indicating the presence of slow interface states A higher interface trap density calculated from the high-low frequency method is observed for the $Al_2O_3/HfO_2$ sample. The parallel conductance method, applied to the accumulation region, shows border traps at 0.3~0.32 eV for the $Al_2O_3/HfO_2$ sample, which are not observed for the $Al_2O_3/HfO_2$ sample. I-V measurements show a reduction of leakage current of about three orders of magnitude for the $HfO_2/Al_2O_3$ sample. Using the Fowler-Nordheim emission, the barrier height is calculated and found to be about 1.08 eV for the $HfO_2/Al_2O_3$ sample. Based on these results, it is suggested that $HfO_2/Al_2O_3$ is a better dielectric stack than $Al_2O_3/HfO_2$ on AlN/p-Ge interface.