• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.3
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• pp.705-711
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• 2013

QRS detection of ECG is the most popular and easy way to detect cardiac-disease. But it is difficult to analyze the ECG signal because of various noise types. Also in the healthcare system that must continuously monitor people's situation, it is necessary to process ECG signal in realtime. In other words, the design of algorithm that exactly detects QRS wave using minimal computation and classifies PVC by analyzing the persons's physical condition and/or environment is needed. Thus, efficient QRS detection and PVC classification based on profiling method is presented in this paper. For this purpose, we detected QRS through the preprocessing method using morphological filter, adaptive threshold, and window. Also, we applied profiling method to classify each patient's normal cardiac behavior through hash function. The performance of R wave detection, normal beat and PVC classification is evaluated by using MIT-BIH arrhythmia database. The achieved scores indicate the average of 99.77% in R wave detection and the rate of 0.65% in normal beat classification error and 93.29% in PVC classification.

• Journal of Sensor Science and Technology
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• v.22 no.5
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• pp.338-345
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• 2013

Premature ventricular contractions are the most common of all arrhythmias and may cause more serious situation like ventricular fibrillation and ventricular tachycardia in some patients. Therefore, the detection of this arrhythmia becomes crucial in the early diagnosis and the prevention of possible life threatening cardiac diseases. Most methods for detecting arrhythmia require pp interval, or the diversity of P wave morphology, but they are difficult to detect the p wave signal because of various noise types. Thus, it is necessary to use noise-free R wave. So, the new approach for the detection of PVC is presented based on the rhythm analysis and the beat matching in this paper. For this purpose, we removed baseline wandering of low frequency band and made summed signals that are composed of two high frequency bands including the frequency component of QRS complex using the wavelet filter. And then we designed R wave detection algorithm using the adaptive threshold and window through RR interval. Also, we developed algorithm to classify PVC using RR interval. The performance of R wave and PVC detection is evaluated by using MIT-BIH arrhythmia database. The achieved scores indicate average detection rate of 99.76%, sensitivity of 99.30% and specificity of 98.66%; accuracy respectively for R wave and PVC detection.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.422-427
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• 2012

This study investigates on the relationship between total load which is caused by infiltration and insulation thickness against compensation effect. As the result of experiment, the PVC(Synthetic resins sash) window frame in airtightness is superior to the AL(Aluminum sash) window frame. In this study, as the increasing of insulation thickness in reference building does not reduce significantly cooling load, the compensation effect due to airtightness against infiltration is very small. But the compensation effect against infiltration can be closely related with heating load. Therefore, the proper thermal insulation thickness can be needed respect to cooling and heating load.

• KIEAE Journal
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• v.13 no.2
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• pp.3-12
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• 2013

Recently, New Han-ok is in prevail because it has many good qualities as a dwelling. But the New Han-ok dwellers' needs and satisfaction ratio on their houses are not investigated yet. So, surveys on satisfaction ratio for New Han-ok were carried out to know New Han-ok's existing conditions and inhabitant's responses on New Han-ok dwellings. Followings are results. 1) Dwellers response that it is cool in summer and it is cold in winter. So, design and construction method against cold is needed for New Han-ok. 2) Window is the most picking element of New Han-ok for house improvement. 3) Window opening is main control method for cooling in summer. Warming sources in winter are various such as electricity, gas, oil, wood, etc. 4) PVC window structure and glasses were used for New Han-ok's window system as well as wooden window structure and Han-gi. 5) Interviewees are generally satisfied with New Han-ok's exterior view and inner spaces. Almost no humidifier is used. These results could be used for improvement of Han-ok and basic material for New Han-ok design.

• Journal of the Korean Solar Energy Society
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• v.40 no.1
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• pp.49-60
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• 2020

This study reviewed selected specific windows and reviewed the window performance certification criteria including KS F 2278 and KS L 9107 and analyzed the change in performance based on the change of area. This study also compared the heating and cooling loads of an apartment house applied with window performance reviewed in consideration of insulation and SHGC performance and actual size based on KS F 2278. The analyzed window was a double window composed of aluminum and PVC and the building was the apartment house model of 141 ㎡. The analysis results were as follows. First, as the window glass's thermal performance is superior to frame, the performance degraded in reduced area. In case of selected window, the 1 m × 1m window's thermal performance and SHGC decreased by 35% and 37% respectively compared to 2 m × 2 m window. Secondly, in the comparison of performance for increasing area with 2 m × 2 m and 3 m × 3 m windows, the 3 m × 3 m window's thermal performance and SHCG increased about 14%. Third, in the comparison of heating and cooling loads of the analyzed model considering the apartment house model applied with window performance derived from KS F 2278 and actual figures, the model's total heating and cooling loads increased by 33% with cooling decreasing by 36% and heating increasing by 77%. Above analysis results show that evaluation of window performance based on criteria such as KS F 2278 and KS L 9107 may lead to distortion of performances different from actual products. Thus, it is necessary to suggest new evaluation criteria.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.451-459
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• 2009

This paper presents an approach to detect premature ventricular contraction(PVC) using discrete wavelet transform and fuzzy neural network. As the input of the algorithm, we use 14 coefficients of d3, d4, and d5, which are transformed by a discrete wavelet transform(DWT). This paper uses a neural network with weighted fuzzy membership functions(NEWFM) to diagnose PVC. The NEWFM discussed in this paper classifies a normal beat and a PVC beat. The size of the window of DWT is $-31/360{\sim}+32/360$ second(64 samples) whose center is the R wave. Using the seven records of the MIT-BIH arrhythmia database used in Shyu's paper, the classification performance of the proposed algorithm is 99.91%, which outperforms the 97.04% of Shyu's analysis. Using the forty records of the M1T-BIH arrhythmia database used in Inan's paper, the classification performance of the proposed algorithm is 98.01%, which outperforms 96.85% of Inan's one. The SE and SP of the proposed algorithm are 84.67% and 99.39%, which outperforms the 82.57% and 98.33%, respectively, of Inan's study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.559-564
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• 2011

The UV blocking type pressure-sensitive adhesive sheet was developed by mixing UV blocking reagent with adhesive material, instead of conventional method in which the reagent was mixed with PVC substrate. The blocking performance of the sheet was evaluated by measuring the absorbance in 280-400 nm region. Both organic and inorganic type blocking reagents were examined. The blocking ability of the former is better than that of the later. Only 1% addition of blocking reagents is effective to block UV light without affecting to visibility and tackiness of adhesive tapes.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1734-1740
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• 2012

Voltammetric characterization of hydrophilic anion transfer processes across a 66 microhole array interface between the water and polyvinylchloride-2-nitrophenyloctylether gel layer is demonstrated. Since the transfer of hydrophilic anions including $Br^-$, $NO_3{^-}$, $I^-$, $SCN^-$ and $ClO_4{^-}$ across the liquid/gel interface usually sets the potential window within a negative potential region, a highly hydrophobic organic electrolyte, tetraoctylammonium tetrakis(pentafluorophenyl)borate, providing a wider potential window was incorporated into the gel phase. The transfer reaction of perchlorate anions across the microhole-water/gel interface was first studied using cyclic voltammetry and differential pulse voltammetry. The full voltammetric response of perchlorate anion transfer was then used as a reference for evaluating the half-wave transfer potentials, the formal transfer potentials and the formal Gibbs transfer energies of more hydrophilic anions such as $Br^-$, $NO_3{^-}$, $I^-$, and $SCN^-$. The current response associated with the perchlorate anion transfer across the micro-water/gel interface versus the perchlorate concentration was also demonstrated for sensing applications.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.10-11
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• 2018

In the building, the opening penetrates the wall and serves as a spreading channel for smoke and flame in case of fire. In Korea, more than 1,500 fire plume are generated annually, and the number has increased by about 30% over the past five years. Therefore, in the case of windows protecting the opening, fire protection performance is important to prevent the spread of fire. However, in Korea, the standard for window is not clear. In this study, fire tests (EN 13823) for windows were conducted in Korea, and then fire protection performance of windows was compared. As a result of the experiment, PVC windows showed a phenomenon that they could not withstand the temperature during the fire experiment, and AL windows showed a difference in the degree of cracking of the glass.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1699-1705
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• 2012

This study was conducted to examine the differences of the quality of chest compression between 10 cm higher position of rescuer's knee from the bottom and its bottom position during implementation of CPR. It selected randomly subjects out of 66 students who attend the Dept. of Emergency Medical Technology in G college, G metropolitan city as the first grader and divided them into 31 experimental group and 32 control group from Nov. 8 to 9, 2011. Mattress was spread 10 cm higher from the bottom(material: B4 Copy Paper) and on the bottom(material: PVC, size: $185{\times}125{\times}0.65cm$) and only chest compression was conducted for 2 minutes. Experiment was conducted with 1 Resusci Anne mannequin and the results of experiment were recorded with Laerdal PC Skill Reporting System. Data collected were analyzed with $x^2$-test and Fisher's exact probability test using SPSS 14.0 for Window, Mann-Whitney U-test, and Wilcoxon signed rank test. As a result of the study, it was found that 10 cm higher position of rescuer knee from the bottom than the bottom position and group below 170 cm in their height and 65 kg in their weight were more effective in proper depth of chest compression and average chest compression depth.