• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5161-5166
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• 2014

Our aim was to access the association between recreational physical activity (RPA) and risk of ovarian cancer (OC). The studies were retrieved from the PubMed and Embase databases up to February 20th, 2014. Risk ratios (OR) and 95% confidence intervals (CI) were used to estimate effect sizes. Random-effects or fixed-effects models were used to pool the data. The trim and fill method was applied for sensitivity analysis. Begg's rank correlation test and Egger's regression asymmetry test were employed to assess the publication bias. A total of 6 studies (435398 participants including 2983 OC patients) were included in this meta-analysis. The overall estimate indicated that there was weakly inverse association between RPA and OC risk (RR=0.90, 95%CI: 0.72-1.12, p=0.335). Meanwhile, for prospective cohort studies, a result consistent with the overall estimate was obtained (RR=1.12, 95% CI: 0.88-1.42, p=0.356). However, for case control studies, the pooled estimate of RR was 0.76 (95%CI: 0.64-0.90, p=0.002), indicating a clear significant association between RPA and OC risk. In addition, the sensitivity analysis indicated a significant link between RPA and risk of OC after removing Lahmann's study (RR=0.80, 95% CI: 0.68-0.93, p=0.004). No significant publication bias was found (Begg's test: p=1.00; Egger's test: p=0.817). In conclusion, our meta-analysis indicated a weakly inverse relationship between RPA and the occurrence of OC.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.1
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• pp.52-58
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• 2012

In this study, the effect of standard phase difference in calibration of carbonyl compounds (CC) was evaluated by using their standards prepared in both gaseous and liquid phase. For this analysis, standards in both phases were prepared for 6 different CCs (formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA) and valeraldehyde (VA)) at similar concentration levels. Their gaseous standard was calibrated after derivatization with three types of DNPH cartridge, and their calibration results were compared against liquid-phase standards. Although there was a strong compatibility between 2 phases for CCs with lower molecular weights (e.g., formaldehyde and acetaldehyde), it was not the case for the heavier CCs. The results of our analysis indicate that the analytical bias of the heavier CCs can be significantly large (by more than a few tens of %). As a result, underestimation of hevier CCs can be significant, if their gaseous samples are quantified by liquid phase standard.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.180-180
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• 2010

The design and implementation of high rate deposition process and anti-scratch property of silicon oxide film by PECVD with UHF power were investigated according to the effect of UHF input power with HF bias. New regime of high rate deposition of SiOx films by hybrid plasma process was investigated. The dissociation of OMCTS (C8H24Si4O4) precursor was controlled by plasma processes. SiOx films were deposited on polyethylene terephthalate (PET) and polycarbonate substrate by plasma enhanced chemical vapor deposition (PECVD) using OMCTS with oxygen carrier gas. As the input energy increased, the deposition rate of SiOx film increased. The plasma diagnostics were performed by optical emission spectrometry. The deposition rate was characterized by alpha-step. The mechanical properties of the coatings were examined by nano-indenter and pencil hardness, respectively. The deposition rate of the SiOx films could be controlled by the appropriate intensity of excited neutrals, ionized atoms and UHF input power with HF bias at room temperature, as well as the dissociation of OMCTS.

• Journal of Korean Traditional Oncology
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• v.21 no.2
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• pp.51-61
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• 2016

Background : Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect in cancer patients who were exposed to chemotherapy. CIPN impacts on the quality of life and could delay chemotherapy. The aim of this review was to assess the therapeutic effectiveness of herbal medicine in CIPN patients. Methods : Randomized controlled trials (RCTs) were included in this review. We searched MEDLINE, Cochrane database, EMBASE, CNKI, Wanfang and four Korean databases without restrictions on time or language. The risk of bias was assessed using the Cochrane risk of bias tool. Results : Eleven RCTs involving 706 patients met the inclusion criteria. Eleven different herbal medicines were examined in the included trials. Almost RCTs showed insufficiency in the reporting randomization method and allocation concealment. One trial used allocation concealment and a double-blinding method. Five studies reported that participants dropped out of RCTs and conducted an 'as-treated analysis'. One trials reported adverse effects of herbal medicine. In ten of the eleven trials, the use of herbal medicine had shown significant differences in clinical symptoms or nerve conduction velocity. Conclusions : The use of herbal medicines for CIPN showed significant improvements in the management of CIPN. However, conclusions cannot be drawn because of the generally low quality of methodology and low quantity of data for each single herbal medicine. Further rigorous trials are needed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.1
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• pp.107-112
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• 2018

One-dimensional numerical model is implemented to investigate temperature variations in the mixed layer depth (MLD) with the passage of typhoons. In the model, we assume a non-divergent, infinite ocean and consider wind effects only, excluding isostatic effects (inverse barometric effects) and upwelling with vertical movement of the water column. Numerical experiments investigate the effects of typhoon tracks on temperature variations, including their dependence on vertical resolutions in the MLD and these results are compared with those in a three-dimensional primitive equation model (POM). The model reproduces features of the observed temperature variations in the MLD fairly well, and implies that wind effects, rather than isostatic effects, play a predominant role in temporal and spatial temperature variations in the MLD. After the passage of typhoons, however, the model does not reproduce well the temperature variations observed in the MLD, because a limitation of the model is its inability to reproduce events such as cyclonic eddy formation (Hong et al., 2011; Masuda and Hong, 2011). The model also shows well the so called 'rightward bias' (Price, 1981) of sea surface cooling which is the most predominant in the right hand side of typhoon's track.

• Journal of the Korean Vacuum Society
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• v.21 no.6
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• pp.322-327
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• 2012

The strain effects of ZnSe epilayer on ZnSe/GaAs heterojunction structure grown by molecular beam epitaxy have been investigated by using electroreflectance (ER) spectroscopy. The ER measurements were performed as a function of modulation voltage, dc bias voltage, and temperature. From the room temperature ER spectrum, we observed a heavy-hole (HH: 2.609 eV) and light-hole (LH: 2.628 eV) transitions due to a compressive strain. With increasing the bias voltage, the amplitude of HH transition signal decreased and the amplitude of LH transition signal was almost the same. From the temperature dependence of ER spectra, we have studied the interaction between the strain and the thermal expansion coefficient.

• Transactions on Electrical and Electronic Materials
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• v.11 no.4
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• pp.166-169
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• 2010

In this study, we changed the etch parameters (gas mixing ratio, radio frequency [RF] power, direct current [DC]-bias voltage, and process pressure) and then monitored the effect on the $HfAlO_3$ thin film etch rate and the selectivity with $SiO_2$. A maximum etch rate of 108.7 nm/min was obtained in $Cl_2$ (3 sccm)/$BCl_3$ (4 sccm)/Ar (16 sccm) plasma. The etch selectivity of $HfAlO_3$ to $SiO_2$ reached 1.11. As the RF power and the DC-bias voltage increased, the etch rate of the $HfAlO_3$ thin film increased. As the process pressure increased, the etch rate of the $HfAlO_3$ thin films increased. The chemical state of the etched surfaces was investigated with X-ray photoelectron spectroscopy. According to the results, the etching of $HfAlO_3$ thin film follows the ion-assisted chemical etching.

• Journal of the Optical Society of Korea
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• v.13 no.4
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• pp.434-438
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• 2009

In this paper, a 12.5-Gb/s optical transmitter is implemented using 0.13-${\mu}m$ CMOS technology. The optical transmitter that we constructed compensates temperature effects of VCSEL (Vertical cavity surface emitting laser) using auto-power control (APC) and auto-modulation control (AMC). An external monitoring photodiode (MPD) detects optical power and modulation. The proposed APC and AMC demonstrate 5$\sim$20-mA of bias-current control and 5$\sim$20-mA of modulation-current control, respectively. To enhance the bandwidth of the optical transmitter, an active feedback amplifier with negative capacitance compensation is exploited. The whole chip consumes only 140.4-mW of DC power at a single 1.8-V supply under the maximum modulation and bias currents, and occupies the area of 1280-${\mu}m$ by 330-${\mu}m$ excluding bonding pads.

• 연구논문집
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• s.28
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• pp.219-227
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• 1998

In order to investigate the interfacial structure between TiN and iron nitride, an AISI 4140 steel was nitrided to form a layer of thickness 15$\mum$ by DC ion nitriding, then the surface was bombarded with Ti ions and subsequently coated a TiN film of 5$\mum$ by arc ion plating method. The interfacial microstructure between TiN and iron nitride was characterized by optical microscope, SEM and XRD. So called black layer was observed in the duplex treatment. It was resulted from the decomposition of iron nitride during the bombardment. Its thickness was increased with increasing bombardment time at high bias voltage. But the thickness was greatly decreased when the iron nitride was bombarded with a nitrogen gas or at a reduced bias voltage. The adhesion strength of the top TiN coating was decreased with increasing thickness of the black layer. Furthermore, the reduced adhesion strength in this system was discussed in view of the interfacial structural relationship between TiN and iron nitride.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.4
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• pp.147-151
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• 2002

The resistances of metal2 contact to metall and poly Si are checked by various RF etch conditions in terms of pre-cleaning. The changes of resistance are evaluated by statistical analysis method(SAS) for the AC bias power, coil power and RF target. The contact area on poly Si is shown by TEM image and the distributions of contact resistance according to ar etch target and RTP are investigated. The RTP groups have larger variations than normal RF etch targets. When the RF etch target becomes lower and coil power becomes higher, the resistances of metal2 contact to metals and poly Si have lower contact resistance. But the condition of AC bias power did not satisfied low meta12 contacts resistance for metall and poly Si simultaneously. The R-square of ststistical analysis was 0.98 for resistances of meta12 contact to poly Si and 0.87 for resistances of meta12 contact to metall.