• Journal of the Institute of Convergence Signal Processing
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• v.8 no.4
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• pp.237-243
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• 2007

In this paper, we propose the Real-time Dead-Pixel Detection and Compensation System for mobile camera and its hardware architecture. The CMOS image sensors as image input devices are becoming popular due to the demand for miniaturized, low-power and cost-effective imaging systems. However a conventional Dead-Pixel Detection Algorithm is disable to detect neighboring dead pixels and it degrades image quality by wrong detection and compensation. To detect dead pixels the proposed system is classifying dead pixels into Hot pixel and Cold pixel. Also, the proposed algorithm is processing line-detector and $5{\times}5$ window-detector consecutively. The line-detector and window-detector can search dead pixels by using one-dimensional(only horizontal) method in low frequency area and two-dimensional(vertical and diagonal) method in high frequency area, respectively. The experimental result shows that it can detect 99% of dead pixels. It was designed in Verilog hardware description language and total gate count is 23K using TSMC 0.25um ASIC library.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.5
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• pp.59-71
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• 2020

Using high-resolution stereoscopic aerial images (in 2008, 2012 and 2016), we conducted to analyze the spatial characteristics affecting evergreen coniferous die-off in the northwestern ridge (major distribution area such as Abies nephrolepis), Seoraksan National Park. The detected number of dead trees at evergreen coniferous forest (5.24㎢) was 1,223 in 2008, was 2,585 in 2012 and was 3,239 in 2016. The number of cumulated dead trees was 7,047 in 2016. In recent years, the number of dead trees increased relatively in the northwest ridge, Seoraksan National Park. Among the analysed spatial factor (altitude, aspect, slope, solar radiation and topographic wetness index), the number of dead trees was increased in the conditions with high altitude, steep slope and dry soil moisture. A spatial distribution of dead tree was divided into 2 groups largely (high altitude with high solar radiation, low altitude with steep slope). In conclusion, the dead trees of evergreen coniferous were concentrated at spatial distribution characteristics causing dryness in the northwestern ridge, Seoraksan National Park.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.285-288
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• 2012

Since the non-overlapping gate driver used in conventional DC-DC boost converters generates fixed dead-times, the converters suffer from the body-diode conduction loss or the charge-sharing loss. To reduce the efficiency degradation due to these losses, this paper presents a PWM DC-DC boost converter with adaptive dead-time control. In light loads, power switching is also employed to increase the efficiency. The designed DC-DC boost converter can thus achieve high efficiency at wide current range. The proposed DC-DC boost converter has 3.3V output from a 2.5V input with 0.18um technology. It operates at 500KHz and has a maximum power efficiency of 97.8%.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.269-273
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• 2004

The hybrid dead time model adopting paralyzable (or extendable) and non-paralyzable (or non-extendable) dead times has been introduced to extend the usable range of G-M counters in high counting rate environment and the relationship between true and observed counting rates is more accurately expressed in the hybrid model. GMSIM, dead time effects simulator, has been developed to analyze the counting statistics of G-M counters using Monte Carlo simulations. GMSIM accurately described the counting statistics of the paralyzable and non-paralyzable models. For G-M counters that follow the hybrid model, the counting statistics behaved in between two idealized models. In the future, GMSIM may be used in predicting counting statistics of three G-M dead time models, which are paralyzable, non-paralyzable and hybrid models.

• Nuclear Engineering and Technology
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• v.3 no.1
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• pp.3-7
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• 1971

A method for determining dead times of a G.M. detector as a function of the count rate has been investigated using the Mn$^{56}$ radioactive sample. The formula, (equation omitted), seems to be useful for determining a relation between the dead time and the count rate. Here (equation omitted)(N$_1$) is the dead time for the count rate N$_1$, N$_1$is the count rate at time zero, Nt is the count rate at time t, λ is the radioactive decay constant of the sample used, and t is the time between the first and second runs. When all the counting data were corrected for the dead times evaluated with this formula and then a variation of these corrected counting data with rime was observed, the results showed quite a good agreement with the published data for the radioactive decay of Mn$^{56}$ . Besides, it appears that the dead time decreases as the count rate increases in a dead time-to-count rate relation obtained by the same formula.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.689-696
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• 2000

In this paper, the cascaded co-channel interference canceller using the dead zone decision is proposed to reduced the co-channel interference in the DS/CDMA communication with the multipath fading and its performance is analyzed. The cancellation scheme creates the replica of the co-channel interference using the data decision of correlator output and removes it at the next stage. The canceller uses the dead zone decision which is detecting strong signal to obtain a good performance in the mobile communication. The results of performance analysis show that the proposed cancellation scheme has the improved performance and the number of user is increased 4 times compared with the conventional receiver, and increased 17% compared with the hard decision. And also the perfect power control is required along with increasing the number of user.

• Journal of Korean Medical Science
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• v.33 no.50
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• pp.326.1-326.10
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• 2018

Background: This retrospective study analyzed the causes of failure in the management process from the identification of brain-dead potential organ donors to actual donation in Korea over the past 5 years. Methods: Data of 8,120 potential brain deaths reported to the Korea Organ Donation Agency were used, including information received at the time of reporting, donation suitability evaluation performed by the coordinator after the report, and data obtained from interviews of hospital medical staff and the donor's family. Results: From January 2012 to December 2016, the total number of brain-dead potential organ donors in Korea was 8,120, of which 2,348 (28.9%) underwent organ procurement surgery with designated recipients. While the number of transplant donors has increased over time, the ratio of transplant donors to medically suitable brain-dead donors has decreased. The common causes of donation failure included donation refusal (27.6%), non-brain death (15.5%), and incompatible donation (11.6%); 104 potential donors (7.8%) were unable to donate their organs because they were not pronounced brain dead. Conclusion: The rate of successful organ donation may be increased by analyzing the major causes of failure in the brain-dead organ donation management process and engaging in various efforts to prevent such failures.

• Journal of IKEEE
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• v.26 no.2
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• pp.271-279
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• 2022

This paper proposes an advanced dead-time compensation method for dual inverter with a floating capacitor. The dual inverter with floating capacitor is composed of double two-level inverters and a bulk electrolytic capacitor. The output voltage of the dual inverter is dropped by the conduction voltage of the power semiconductors. The voltage drop and dead-time cause the fundamental and harmonic distortions of output currents. When supplied power for OEW-load is low, the dual inverter operates as single inverter for effective operation. The dead-time compensation method for the dual inverter operated as single inverter is needed for reliability. The proposed method using band pass filter in this paper compensates dead-time, dead-time error and changed voltage drop error of power semiconductors for the dual inverter and dual inverter operated as single inverter. The effectiveness of the proposed method is verified by simulation results.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.10b
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• pp.85-88
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• 1999

• (The) Research of the performance art and culture
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• no.22
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• pp.63-92
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• 2011

This paper intends to clarify the characteristics of Seoul Ginoguigut in ritual form. This paper points out three characteristics; materialization of the journey to the world of the dead, direct communications with the dead, inclusive blessings for the dead and the living. Firstly, the journey to the world of the dead is materialized through various ritual processes of Seoul Ginoguigut. This characteristic is prominent in the context of comparisons with the death rituals of Confucianism and Buddhism, and of shamanism in other regions of Korea. Secondly, in Seoul Ginoguigut the communications of the dead and the living are made through direct dialogues between them through shaman's possession. The communications by direct dialogues between the dead and the living make it easy to accept death as a real fact, and have an effect of recognizing the individuality and uniqueness of each death. Thirdly, the blessings of Seoul Ginoguigut are so inclusive that they cover the dead's safe journey toward the world of the dead as well as the happiness of the living. This characteristic is related to the understanding of death of Korean shamanism that does not separate death and living. These three characteristics are perceived in the context of comparisons with the death rituals of Confucianism and Buddhism, and of Seoul Ginoguigut. And they give a clue to understand how the death rituals of Korean shamanism have persisted in Korean society.