• Journal of Broadcast Engineering
• /
• v.10 no.3
• /
• pp.413-421
• /
• 2005

As the population of HDTV is growing, among many useful features of modern set top boxes (STBs) or digital video recorders (DVRs), video browsing, visual bookmark, and picture-in-picture capabilities are very frequently required. These features typically employ reduced-size versions of video frames, or thumbnail images. Most thumbnail generation approaches generate DC images directly from a compressed video stream. A discrete cosine transform (DCT) coefficient for which the frequency is zero in both dimensions in a compressed block is called a DC coefficient and is simply used to construct a DC image. If a block has been encoded with field DCT, a few AC coefficients are needed to generate the DC image in addition to a DC coefficient. However, the bit length of a codeword coded with variable length coding (VLC) cannot be determined until the previous VLC codeword has been decoded, thus it is required that all codewords should be fully decoded regardless of their necessary for DC image generation. In this paper, we propose a method especially for fast DC image generation from an I-frame using multiple-symbol lookup table (mLUT). The experimental results show that the method using the mLUT improves the performance greatly by reducing LUT count by 50$\%$.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.59 no.4
• /
• pp.462-466
• /
• 2010

The purpose of this study is to evaluate the safety of a wire connector fabricated for the effective installation of a lighting fixture including its contact resistance, insulation resistance, withstanding voltage characteristics, etc., and to provide the basis for the analysis and judgment of PL(Product Liability) dispute by presenting a damage pattern due to a general flame and overcurrent. This study applied the Korean Standard (KS) for the incombustibility test of the connector using a general flame and performed an overcurrent characteristics test of the connector using PCITS (Primary Current Injection Test System). The contact resistance of the housing connector was measured using a high resistance meter and the insulation resistance was measured using a multimeter. In addition, a supply voltage of AC 1,500V for testing the withstanding voltage characteristics was applied to both ends of the connector. Measurement was performed on 5 specimens and the measured values were used as a basis for judgment. Since the connector is fabricated in the form of a housing, it can be connected and separated easily and has a structure that allows no foreign material to enter. In addition, since it has a structure that allows wires to be connected only when their polarity is identical, any misconnection that may occur during installation can be prevented. When the incombustibility test was performed by applying a general flame to the connector, it showed outstanding incombustibility characteristics and the blade and blade holder connected to the housing remained firmly secured even after the insulation sheath (PVC) was completely destroyed by fire. In addition, the mechanism of the damaged connecting wire showed a comparatively uniform carbonization pattern and it was found that some residual melted insulation material was attached to both ends. In the accelerated life test (ALT) to which approximately 500% of the rated current was applied, the connector damage proceeded in the order of white smoke generation, wire separation, spark occurrence and carbonization. That is, it could be seen that the connector damaged by overcurrent lost its own metallic color with traces of discoloration and carbonization. The contact resistance of the connector at a normal state was 2.164mV/A on average. The contact resistance measured after the high temperature test was 3.258mV/A. In addition, the insulation resistance after the temperature test was completed was greater than $10G\Omega$ and the withstanding voltage test result showed that no insulation breakdown occurred to all specimens showing stable withstanding voltage and insulation resistance characteristics.

• Elastomers and Composites
• /
• v.38 no.3
• /
• pp.227-234
• /
• 2003

Silicone composites for high voltage insulator (HVI SC) were prepared by adding aluminum trihydrate(ATH) treated by surface treatment agent to base silicone compound at the ratio oi 100:20, 100:40, 100:60, 100:80, and 100:100, respectively And also, ATH was treated by various surface treatment agents, such as stearic arid, acryl silane, and vinyl silane under compounding process. Mechanical properties and electrical properties were investigated for the various contents of ATH and surface-treatment agents. Mechanical properties such as tensile strength, elongation, and tear strength decreased as the load of ATH increased. Volume resistivity, AC break down strength, and tracking resistance for HVI SC containing ATH treated by vinyl silane were better than those for HVI SC containing ATH treated by other surface treatment agents, such as stearic acid and acryl silane. Polymer-filler interaction of silicone composites according to surface treatment agents was studied by measuring bound rubber contend(BR). From the experimental results, BR of silicone composite containing ATH treated with vinyl silane was higher than that of the others. The degree of rule for silicone composite was investigated using Rheometer. Maximum torque of silicone composites contaning ATH treated with vinyl silane was higher than that of silicone composite contaning ATH treated with other surface agents.

• Annals of Coloproctology
• /
• v.34 no.6
• /
• pp.286-291
• /
• 2018

Purpose: Stage-IIIC colon cancer is an advanced disease; however, its oncologic outcomes and prognostic factors remain unclear. In this study, we aimed to determine the predictors of disease-free survival (DFS) in patients with stage-IIIC colon cancer. Methods: From a multicenter database, we retrospectively enrolled 611 patients (355 men and 256 women) who had undergone a potentially curative resection for a stage-IIIC colon adenocarcinoma between 2003 and 2011. The primary endpoint was the 5-year DFS. Results: The median age was 62 years; 213 and 398 patients had right-sided colon cancer (RCC) and left-sided colon cancer (LCC), respectively. The 5-year DFS in all patients was 52.0%; median follow-up time was 35 months (range, 1-134 months). A multivariate Cox regression revealed that female sex (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.19-1.90; P < 0.01), right-sided tumor location (HR, 1.65; 95% CI, 1.29-2.11; P < 0.01), lymphatic invasion (HR, 1.52; 95% CI, 1.08-2.15; P < 0.01) and a high (${\geq}0.4$) metastatic lymph node ratio (HR, 3.72; 95% CI, 2.63-5.24; P < 0.01) were independent predictors of worse 5-year DFS. Female patients with RCC were 1.79 fold more likely to experience recurrence than male patients with LCC. Conclusion: Female sex and right-sided tumor location are associated with higher tumor recurrence rates in patients with stage-IIIC colon cancers. Aggressive treatment and close surveillance should be planned for patients in these groups.

• Food Engineering Progress
• /
• v.14 no.3
• /
• pp.249-255
• /
• 2010

Ten commercial activated carbons (ACs) prepared from four different sources (bamboo, wood, peat, and coal) were evaluated for their adsorptive efficiency of six volatile compounds (isoamyl alcohol, hexanal, furfural, ethyl lactate, ethyl octanoate, 2-phenyl ethanol) which were dissolved in a 30% alcoholic model solution. These six volatile compounds are frequently found in alcoholic beverages and possibly contribute to physiological hangover due to their high concentrations. They are also generally regarded as off-flavor compounds at certain levels in alcoholic beverages such as whisky and vodka. Two hundred mL of 30% alcoholic solutions containing these six volatile compounds were treated with 0.2 g of ACs while stirring for 16 hr; the treated solutions were then measured for their adsorptive efficiencies (or removal efficiencies) by gas chromatographic analysis using two different sampling methods (direct liquid injection and headspace-solid phase microextraction). The adsorptive efficiencies of the ACs varied depending on the identity of the volatile compounds and the source material used for making the ACs. Ethyl octanoate, 2-phenyl ethanol, and hexanal were removed at high efficiencies (34-100%), whereas isoamyl alcohol, ethyl lactate, and furfural were removed at low efficiencies (5-13%). AC prepared from bamboo showed a high removal efficiency for isoamyl alcohol, aldehydes (hexanal and furfural), and 2-phenyl ethanol; these major fusel oils have been implicated as congeners responsible for alcohol hangover.

• Journal of Radiation Industry
• /
• v.17 no.4
• /
• pp.471-479
• /
• 2023

In In-situ radioactivity measurement techniques, efficiency calibration models use predefined models to simulate a sample's geometry and radioactivity distribution. However, simplified efficiency calibration models lead to uncertainties in the efficiency curves, which in turn affect the radioactivity concentration results. This study aims to develop an efficiency calibration optimization methodology to improve the accuracy of in-situ gamma radiation measurements for byproducts from industrial facilities. To accomplish the objective, a drive mechanism for rotational measurement of an byproduct simulator and a sample was constructed. Using ISOCS, an efficiency calibration model of the designed object was generated. Then, the sensitivity analysis of the efficiency calibration model was performed, and the efficiency curve of the efficiency calibration model was optimized using the sensitivity analysis results. Finally, the radiation concentration of the simulated subject was estimated, compared, and evaluated with the designed certification value. For the sensitivity assessment of the influencing factors of the efficiency calibration model, the ISOCS Uncertainty Estimator was used for the horizontal and vertical size and density of the measured object. The standard deviation of the measurement efficiency as a function of the longitudinal size and density of the efficiency calibration model decreased with increasing energy region. When using the optimized efficiency calibration model, the measurement efficiency using IUE was improved compared to the measurement efficiency using ISOCS at the energy of ²²⁸Ac (911 keV) for the nuclide under analysis. Using the ISOCS efficiency calibration method, the difference between the measured radiation concentration and the design value for each simulated subject measurement direction was 4.1% (1% to 10%) on average. The difference between the estimated radioactivity concentration and the design value was 3.6% (1~8%) on average when using the ISOCS IUE efficiency calibration method, which was closer to the design value than the efficiency calibration method using ISOCS. In other words, the estimated radioactivity concentration using the optimized efficiency curve was similar to the designed radioactivity concentration. The results of this study can be utilized as the main basis for the development of regulatory technologies for the treatment and disposal of waste generated during the operation, maintenance, and facility replacement of domestic byproduct generation facilities.

• Journal of Animal Science and Technology
• /
• v.45 no.6
• /
• pp.939-948
• /
• 2003

The objective of this study was to identify the quantitative traits loci(QTL) for economically important traits such as growth, carcass and meat quality on pig chromosome 6. A three generation resource population was constructed from cross between Korean native boars and Landrace sows. A total of 240 F$_2$ animals were produced using intercross between 10 boars and 31 sows of F$_1$ animals. Phenotypic data including body weight at 3 weeks, backfat thickness, muscle pH, shear force and crude protein level were collected from F$_2$ animals. Animals including grandparents(F$_0$), parents(F$_1$) and offspring(F$_2$) were genotyped for 29 microsatellite markers and PCR-RFLP marker on chromosome 6. The linkage analysis was performed using CRI-MAP software version 2.4(Green et al., 1990) with FIXED option to obtain the map distances. The total length of SSC6 linkage map estimated in this study was 169.3cM. The average distance between adjacent markers was 6.05cM. For mapping of QTL, we used F$_2$ QTL Analysis Servlet of QTL express, a web-based QTL mapping tool(http://qtl.cap.ed.ac.uk). Five QTLs were detected at 5% chromosome-wide level for body weight of 3 weeks of age, shear force, meat pH at 24 hours after slaughtering, backfat thickness and crude protein level on SSC6.

• Journal of Animal Science and Technology
• /
• v.45 no.5
• /
• pp.679-688
• /
• 2003

The leptin receptor gene(LEPR) produces a high affinity receptor that mediates the regulation of the leptin gene. Leptin secreted from adipose tissue plays an important role in regulating feed intake and energy balance. In this study, a microsatellite marker within LEPR was selected and genotyped for the F2 population composed of 354 individuals from an intercross between Korean Native boars and Landrace sows. Totally, six alleles (255, 259, 261, 263, 265 and 267bp) and nineteen genotypes were detected in the population, of which the CE (261/265), CC (261/261) and EE (265/265) types were observed by 20.0%, 10.1% and 9.6%, respectively. Relationships between their genotypes and economic traits were analyzed. We found specific genotypes associated with economic traits such as body weight at 12 weeks of age/body fat including abdominal and trimmed fat/shear force (P〈0.001), body weight of 30 weeks of age (P〈0.01) and body weight of 3 weeks of age/back fat thickness (P〈0.05). The DD (263/263) and DF (263/267) types were associated with body weight at 3, 5, 12 and 30 weeks of age. The DF (263/267) type showed a highly significant effect on back fat thickness and body fat including abdominal and trimmed fat. The DF (263/267) type showed positive effect on shear force, whereas the BB (259/259) and DD (263/263) types negatively affected on tenderness.

• Korean Journal of Breeding Science
• /
• v.50 no.4
• /
• pp.406-414
• /
• 2018

This study was conducted to develop environmental risk assessments and biosafety guides for insect-resistant genetically modified rice in an LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-T), rice resistant to Cnaphalocrocis medinalis, and non-GM rice (Dongjin-byeo and Ilmi-byeo) were investigated. The Bt-T plants were, therefore, evaluated under field conditions to detect possible impacts on above ground insects and spiders. In 2016 and 2017, the study compared transgenic rice and two non-GM reference rice, namely Dongjin-byeo and Ilmi-byeo, at Gunwi. A total of 9,552 individuals from 51 families and 11 orders were collected from the LMO isolation field. From the three types of rice fields, a total of 3,042; 3,212; and 3,297 individuals from the Bt-T, Dongjin-byeo, and Ilmi-byeo were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies, and other insects on the Bt-T compared to non-GM rice. The data on insect species population densities were subjected to principal component analysis (PCA) without distinguishing between the three varieties, namely GM, non-GM, and reference cultivar, in all cultivation years. However, the PCA clearly separated the samples based on the cultivation years. These results suggest that insect species diversities and population densities during plant cultivation are determined by environmental factors (growing condition and seasons) rather than by genetic factors.

• Radiation Oncology Journal
• /
• v.18 no.4
• /
• pp.337-344
• /
• 2000

Purpose :To design and test test CT simulator phantom for geometrical test. Materials and Methods : The PMMA phantom was designed as a cylinder which is 20 cm in diameter and 24 cm in length, along with a 25$\times25\times31cm^{3}$ rectangular parallelepiped. Radio-opaque wires of which diameter is 0.8 mm are attached on the other surface of the phantom as a spiral. The rectangular phantom was made of four 24$\times24\times0.5 cm^{3}$ square plates and each plate had a 24$\times24 cm^{2}$, 12$\times12cm^{2}$, 6$\times6 cm$^{2}$ square line. The squares were placed to face the cylinder at angles 0 $^{\circ}$ , 15 $^{\circ}$ , 30 $^{\circ}$ ,respectively. The rectangular phantom made it possible to measure the field size, couch angle, the collimator angle, the isocenter shift and the SSD, the measurements of the gantry angle from the cylindrical part. A virtual simulation software, AcOSim, offered various conditions to perform virtual simulations and these results were used to perform the geometrical Quality assurance of CT simulator. Results : A 0.3$\~$0.5 mm difference was found on the 24 cm field size which was created with the DRR measurements obtained by scanning of the rectangular phantom. The isocenter shift, the collimator rotation, the couch rotation, and the gantry rotation test showed 0.5$\~$1 mm, 0.5$\~$l$^{\circ}$ 0.5$\~$ 1$^{\circ}$ , and 0.5-1 $^{\circ}$ differences, respectively. We could not find any significant differences between the results from the two scanning methods. Conclusion :The geometrical test phantom developed in the study showed less than 1 mm (or 1 $^{\circ}$ ) differences. The phantom could be used as a routine geometrical QC/QA tools, since the differences are within clinically acceptable ranges.