• Journal of Power Electronics
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• v.6 no.1
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• pp.73-82
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• 2006

Plasma display panels (PDPs) have a serious thermal problem, because the luminance efficiency of a conventional PDP is about 1.5 1m/W and it is less than $3\~5\;lm/W$ of a cathode ray tube (CRT). Thus there is a need for improving the luminance efficiency of the PDP. There are several approaches to improve the luminance efficiency of the PDP and we adopted a driving PDP at high frequency range from 400kHz up to over 700kHz. Since a PDP is regarded as an equivalent inherent capacitance, many types of sustaining drivers have been proposed and widely used to recover the energy stored in the PDP. However, these circuits have some drawbacks for driving PDPs at high frequency ranges. In this paper, we investigate the effect of the parasitic components on the PDP itself and on the driver when the reactive energy of the panel is recovered. Various drivers are classified and evaluated based on their suitability for high frequency drivers. Finally, a current-fed driver with a DC input voltage bias is proposed. This driver overcomes the effect of parasitic components in the panel and driver. It fully achieves a ZVS of all full-bridge switches and reduces the transition time of the panel polarity. It is tested to validate the high frequency sustaining driver and the experimental results are presented.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.8
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• pp.407-414
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• 2004

In this paper, a new gray scale expression method that divides the scan lines into multiple blocks is suggested. The proposed method can drive 16 sub-fields per 1 TV field in the panel with XGA ($1366{\times}768$) resolution. The on and off states of even subfields depend on the condition of odd subfields. The write address mode is used in the odd subfields, while the erase address mode is used in the even subfields. Because the ramp reset pulse is applied every 2 sub-fields, both the contrast ratio and the dynamic voltage margin are sufficiently obtained in comparison with previous AWD (Address While Display) methods. In realizing 16 subfields, shortening the scan time in the erase address period was important. The X bias voltage in the erase address period affected the minimum address voltage but did not the delay time of the address discharge. The delay time of the address discharge was affected by the address voltage and the time interval between the last sustain discharge and the scanning time. We also evaluated the dynamic false contour. New method shows an improved image quality in horizontal moving, but discontinuous lines were observed at the boundaries of each block in vertical moving

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1203-1206
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• 2005

Electron temperature and plasma density in coplanar alternating-current plasma display panels (AC-PDP's) have been experimentally investigated in accordance with discharge time by a micro-probe in this experiment. The resolution of a step mortor to move in micro-Langmuir probe is 10um.[1-3] The used gas in this experiment is He-Ne-Xe (4%) mixure gas. And sustain voltage is 320V which is above of firing voltage for degradation. The electron temperature and plasma density can be obtained from current-voltage (I-V) characteristics of micro Langmuir probe, in which negative to positive bias voltage was applied to the probe. And Efficiency is calculated by formula related discharge power and light emission. Those experiments operated as various discharge time ($0{\sim}72$ Hours). As a result of this experiment, Electron Temperature was increased from 2eV to 5eV after discharge running time of 20 hours and saturates beyond 20 hours. The plasma density is inversely proportional to the square root of electron temperature. So the plasma density was decreased from $1.8{\times}10^{12}cm^{-3}$ to $8{\times}10^{11}cm^{-3}$ at above discharge running time. And the Efficiency was reduced to 70% at 60hours of discharge running time.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4627-4630
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• 2012

Purpose: Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms have been reported to be associated with pancreatic cancer, but the published studies have yielded inconsistent results. This study assessed the relationship between MTHFR gene polymorphisms and the risk for pancreatic cancer using a meta-analysis approach. Methods:A search of Google scholar, PubMed, Cochrane Library and CNKI databases before April 2012 was performed, and then associations of the MTHFR polymorphisms with pancreatic cancer risk were summarized. The association was assessed by odds ratios (ORs) with 95% confidence intervals (CIs). Publication bias was also calculated. Results: Four relative studies on MTHFR gene polymorphisms (C667T and A1298C) were included in this meta-analysis. Overall, C667T (TT vs. CC:OR=1.61,95%CI=0.78-3.34; TT vs. CT: OR=1.41,95%CI=0.88-2.25; Dominant model:OR=0.68,95%CI=0.40-1.17; Recessive model: OR=0.82,95%CI=0.52-1.30) and A1298C (CC vs. AA:OR=1.01,95%CI=0.47-2.17; CC vs. AC: OR=0.99,95%CI=0.46-2.14; Dominant model:OR=1.01, 95%CI=0.47-2.20; Recessive model: OR=1.01,95%CI=0.80-1.26) did not increase pancreatic cancer risk. Conclusions: This meta-analysis indicated that MTHFR polymorphisms (C667T and A1298C) are not associated with pancreatic cancer risk.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9241-9247
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• 2014

Background: Rs31489 in the cleft lip and palate transmembrane1-like gene (CLPTM1L) has been identified to be associated with lung cancer through genome-wide association studies (GWAS). However, some recent replication studies yielded inconclusive results. Thus, we undertook this study to investigate the precise effect of rs31489 on lung cancer susceptibility. Materials and Methods: A hospital-based case-control study in 1,673 Chinese subjects (611 individuals with lung cancer and 1,062 controls) and a meta-analysis among 32,199 subjects (16,364 cases and 15,835 controls) were performed in this study. Results: In our case-control study, rs31489 was inversely associated with lung cancer (AC versus CC: OR=0.68, 95%CI=0.52-0.88; additive model: OR=0.68, 95%CI=0.54-0.85; dominant model: OR=0.65, 95%CI =0.51-0.84). Stratification analysis by smoking status showed a significant association and strong genetic effect in non-smokers but not in smokers. Our meta-analysis further confirmed the association, although with significant heterogeneity contributed by study design and source of controls, as shown by stratified analysis. Sensitive and cumulative analyses both indicated robust stability of our results. In addition, there was no observable publication bias in our meta-analysis. Conclusions: Overall, the findings from our replication study and meta-analysis demonstrated that CLPTM1L gene rs31489 is significantly associated with lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2249-2252
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• 2012

Objective: Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms have been reported to be associated with pancreatic cancer, but the published studies had yielded inconsistent results.We therefore performed the present meta-analysis. Methods: A search of Google scholar, PubMed, Cochrane Library and CNKI databases before April 2012 was conducted to summarize associations of MTHFR polymorphisms with pancreatic cancer risk. Assessment was with odds ratios (ORs) and 95% confidence intervals (CIs). Publication bias were also calculated. Results: Four relative studies on MTHFR gene polymorphisms (C667T and A1298C) were involved in this meta-analysis. Overall, C667T(TT vs. CC : OR = 1.61, 95%CI = 0.78 - 3.34; TT vs. CT : OR = 1.41, 95%CI = 0.88-2.25; dominant model: OR = 0.68, 95%CI = 0.40-1.17; recessive model: OR = 0.82, 95%CI = 0.52-1.30) and A1298C(CC vs. AA:OR=1.01, 95%CI=0.47-2.17; CC vs. AC: OR=0.99,95%CI=0.46-2.14; dominant model: OR=1.01, 95%CI = 0.47-2.20; recessive model: OR = 1.01, 95%CI = 0.80-1.26) did not increase pancreatic cancer risk. Conclusion: This meta-analysis indicated that MTHFR polymorphisms (C667T and A1298C) were not associated with pancreatic cancer risk.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.600-603
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• 2008

In this paper, a new circuit design named memory-in-pixel for low power consumption of the liquid crystal display (LCD) is presented. Since each pixel has a memory, it is able to express 8 color grades using the data saved in the memory without the operation of the gate and source driver ICs so that it can reduce the power consumption of the LCD panel. A memory circuit consists of modified S-R flip-flop (NAND-type) implemented in the pixel, which can supply AC bias for operating the liquid crystal (LC) with the interlocking clocks (CLK_A and CLK_B). This circuit is more complex than the inverter-type memory circuit, but it has lower power consumption of approximately 50% than the circuit. We have investigated the power consumption both NAND and inverter-type memory circuit using a Smart SPICE for the resolution of $96{\times}128$. The estimated power consumption of the inverter-type memory was about 0.037mW. On the other hand, the NAND-type memory showed power consumption of about 0.007mW.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.4
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• pp.67-72
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• 2022

This study presents the design of power amplifier (PA) in 60 nm GaN/Si HEMT technology. A customized transistor model enables the designing circuits operating at W-band. The all matching network of the PA was composed of equivalent transformer circuit to reduce matching loss. And then, equivalent transformer is several advantages without any additional inductive devices so that a wideband power characteristic can be achieved. The designed die area is 3900 ㎛ × 2300 ㎛. The designed results at center frequency achieved the small signal gain of 15.9 dB, the saturated output power (Psat) of 29.9 dBm, and the power added efficiency (PAE) of 24.2% at the supply voltage of 12 V.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.2
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• pp.88-98
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• 2023

Purpose: Children with inflammatory bowel disease (IBD) frequently undergo clinical assessments, involving triadic communication between clinician, parent, and child. During such encounters parents are traditionally the main communicator of information on their child's IBD, including subjective symptom reports. The level of agreement between children and their parents for IBD symptoms is poorly understood, and this study aimed to examine this factor. Methods: This was a cross-sectional study among children with IBD, and one parent. A validated paediatric IBD symptom report tool (IBDnow) enabled children and their parent to rate seven pain, well-being, and stool metrics, with dyads completing the tool concurrently. Results were assessed using: Individual agreement: proportion of identical symptom reports by each dyad (ideal score >0.7); Category agreement: percentage of identical reports for IBDnow metrics for the cohort; Inter-rater reliability: Gwet's AC1 coefficient with higher scores indicating better reliability (maximum=1). Results: Seventy-four parent/child dyads participated; child's mean age 12.2 years (standard deviation [SD] 2.9, range 6-16), mean time since diagnosis 2.8 years (SD 3), 54% female, 73% had Crohn's Disease. Mean individual agreement level was 0.6, with 27% of dyads agreeing on ≥6/7 IBDnow metrics. Category agreement was reported by 61% of dyads, 20% of parents overestimated, and 19% underestimated, their child's symptoms. Inter-rater reliability ranged from fair to good. Conclusion: These results should improve clinician awareness of how IBD symptom reports from parents may introduce bias. Children should be considered the most important source of symptom reports, and tools such as IBDnow utilised to enhance communication.

• Journal of Gastric Cancer
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• v.20 no.2
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• pp.152-164
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• 2020

Purpose: To compare long-term disease-free survival (DFS) between patients receiving tegafur/gimeracil/oteracil (S-1) or capecitabine plus oxaliplatin (CAPOX) adjuvant chemotherapy (AC) for gastric cancer (GC). Materials and Methods: This retrospective multicenter observational study enrolled 983 patients who underwent curative gastrectomy with consecutive AC with S-1 or CAPOX for stage II or III GC at 27 hospitals in Korea between February 2012 and December 2013. We conducted propensity score matching to reduce selection bias. Long-term oncologic outcomes, including DFS rate over 5 years (over-5yr DFS), were analyzed postoperatively. Results: The median and longest follow-up period were 59.0 and 87.6 months, respectively. DFS rate did not differ between patients who received S-1 and CAPOX for pathologic stage II (P=0.677) and stage III (P=0.899) GC. Moreover, hazard ratio (HR) for recurrence did not differ significantly between S-1 and CAPOX (reference) in stage II (HR, 1.846; 95% confidence interval [CI], 0.693-4.919; P=0.220) and stage III (HR, 0.942; 95% CI, 0.664-1.337; P=0.738) GC. After adjustment for significance in multivariate analysis, pT (4 vs. 1) (HR, 11.667; 95% CI, 1.595-85.351; P=0.016), pN stage (0 vs. 3) (HR, 2.788; 95% CI, 1.502-5.174; P=0.001), and completion of planned chemotherapy (HR, 2.213; 95% CI, 1.618-3.028; P<0.001) were determined as independent prognostic factors for DFS. Conclusions: S-1 and CAPOX AC regimens did not show significant difference in over-5yr DFS after curative gastrectomy in patients with stage II or III GC. The pT, pN stage, and completion of planned chemotherapy were prognostic factors for GC recurrence.