• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.10
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• pp.1167-1175
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• 2016

This paper proposes an efficient page-level mapping algorithm that reduces the erase count in the FTL for flash memory systems. By maintaining the weight for each write request in the request buffer, the proposed algorithm estimates the degree of temporal locality for each incoming write request. To exploit temporal locality deliberately for determination of hot request, the degree of temporal locality should be much higher than the reference point determined experimentally. While previous LRU algorithm treats a new write request to have high temporal locality, the proposed algorithm allows write requests that are estimated to have high temporal locality to access hot blocks to store hot data intensively. The pages are more frequently updated in hot blocks than warm blocks. A hot block that has most of invalid pages is always selected as victim block at Garbage Collection, which results in delayed erase operation and in reduced erase count. Experimental results show that erase count is reduced by 9.3% for real I/O workloads, when compared to the previous LRU algorithm.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.6
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• pp.1-8
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• 2000

In this paper, design of sense amplifier for a flash memory minimizing bit line disturbance due to common bit line is presented. There is a disturbance problem at output modes by using common bit line, when the external devices access an internal flash memory. This phenomenon is resulted form hot carrier between floating gates and bit lines by thin oxide thickness. To minimize bit line disturbance, lower it line voltage is required and need sense amplifier to detect data existence in lower bit line voltage. Proposed circuits is operated at lower bit line voltage and we fabricated a embedded flash memory MCU using 0.6u technology.

• IEMEK Journal of Embedded Systems and Applications
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• v.11 no.2
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• pp.125-134
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• 2016

NAND flash memory has unique characteristics like as 'out-place-update' and limited lifetime compared with traditional storage systems. According to out-of-place update scheme, a number of invalid (or called dead) pages can be generated. In this case, garbage collection is needed to reclaim invalid pages. Because garbage collection results in not only erase operations but also copy operations of valid (or called live) pages to other blocks, many garbage collection techniques have proposed to reduce the overhead and to increase the lifetime of NAND Flash systems. This techniques sometimes select victim blocks including cold data for the wear leveling. However, most of them overlook the cost of selecting victim blocks including cold data. In this paper, we propose a garbage collection technique named CAPi (Cost Age with Proportion of invalid pages). Considering the additional overhead of what to select victim blocks including cold data, CAPi improves the response time in garbage collection and increase the lifetime in memory systems. Additionally, the proposed scheme also improves the efficiency of garbage collection by separating cold data from hot data in valid pages. In experimental evaluation, we showed that CAPi yields up to, at maximum, 73% improvement in lifetime compared with existing garbage collections.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.331-331
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• 2012

With the NAND Flash scaling down, it becomes more and more difficult to follow Moore's law to continue the scaling due to physical limitations. Recently, three-dimensional (3D) flash memories have introduced as an ideal solution for ultra-high-density data storage. In 3D flash memory, as the process reason, we need to use poly-Si TFTs instead of conventional transistors. So, after combining charge trap flash (CTF) structure and poly-Si TFTs, the emerging device SONOS-TFTs has also suffered from some reliability problem such as hot carrier degradation, charge-trapping-induced parasitic capacitance and resistance which both create interface traps. Charge pumping method is a useful tool to investigate the degradation phenomenon related to interface trap creation. However, the curves for charge pumping current in SONOS TFTs were far from ideal, which previously due to the fabrication process or some unknown traps. It needs an optimization and the important geometrical effect should be eliminated. In spite of its importance, it is still not deeply studied. In our work, base-level sweep model was applied in SONOS TFTs, and the nonideal charge pumping current was optimized by adjusting the gate pulse transition time. As a result, after the optimizing, an improved charge pumping current curve is obtained.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.199-203
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• 2003

Idler of excavator are large product with diameter 500 - 600 mm and parts of a power transmit device. The object of the paper is developed large products by hot closed-die forging. The forging process which is proposed from numerical analysis and various tests is developed a large products with good quality. To estimate the design process parameters such as working load, temperature and flash thickness so on, numerical analysis are used by DEFORM 2D. To obtain a flow stress data and optimal forging temperature is carried out hot compression and tensile test at a various temperature range. Developed product is tested mechanical properties of elongation, hardness and tensile strength so on. Test results are presented excellent mechanical properties.

• Korean Journal of Adult Nursing
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• v.26 no.2
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• pp.159-170
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• 2014

Purpose: This research investigated the degree and predictors of hot flashes and hypogonadism symptoms in patients with prostate cancer receiving hormone replacement therapy. Methods: The subjects were 111 patients with prostate cancer receiving hormone replacement therapy in two university hospitals located in D city. The measurement tools included Hot Flash Diary and AMS (Aging Male's Symptoms rating scales). The data were analyzed using t-test, ANOVA, and binary logistic regression analysis. Results: The percentage of patients who experienced hot flashes among the participants was 14.4%. The predictors for hot flashes were eating irregularly, having coffee frequently and the types of hormone. The average score of hypogonadism symptom was 2.16 out of five-point scale and the highest score of hypogonadism symptom was the sexual symptoms (2.77 out of five-point scale). The predictors for hypogonadism symptom were eating habits and years of having the illness. Conclusion: These findings provide the information that irregularly eating habit was an important factor in hot flashes and hypogonadism symptoms of the participants. Therefore the development of a nutritional education encouraging regular meals is necessary for the given population.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.4
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• pp.188-196
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• 2018

Objectives: This study is to report the clinical effectiveness of the complex Korean medicine therapy on a postoperative endometriosis patient's hypoestrogenic side effects who is treated with GnRH-agonist injection. Methods: The patient in this case was diagnosed with endometriosis and has been treated with GnRH-a injection after laparoscopic operation. The patient complained hot flash and sweating mainly after GnRH-a treatment. The patient received complex Korean medicine therapy during 10 days admission period. The clinical effects were evaluated through KI (Kupperman's Index) and SF-36 (36 item Short Form Health Survey). Results: After the complex Korean medicine therapy, the various clinical symptoms including hot flash and sweating were improved. Also, the quality of life was enhanced. Conclusions: This case report shows that the complex Korean medicine therapy was effective for treating hypoestrogenic side effects occurred after GnRH-a treatment in postoperative endometriosis patient.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.68-77
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• 2010

In this paper, we propose a new log buffer management scheme considering the accessibility of the data. Our proposed scheme evaluates the worth of the merge of log blocks. It conducts the merge operations between infrequently updated data and the data blocks and postpones as much as possible the merge operations between frequently updated data and the data blocks. As a result, the proposed method prevents the unnecessary merge operations, reduces the number of the erase operations, and improves the utilization of the flash memory storage. In order to show the superiority of the proposed scheme, we compare it with BAST and FAST. It is shown through performance evaluation that the proposed method achieves about 25% and 65% performance improvements over BAST and FAST on average in terms of the number of the erase operations.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.1
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• pp.87-98
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• 2011

Objectives: To evaluate the clinical use of Kupperman's Index, Menopausespecific quality of life questionnaire(MENQOL), Menopause Rating Scale(MRS) by comparison with the Subjective measures of hot flush. Methods: The participants were 107 women (45-60 yr) who were not currently on hormone therapy, and had reached hot flash scores of 10 or higher. The evaluating indexes of this trial are hot flush score, hot flush VAS, Hot flush consistence time, sweating VAS, Kupperman`s Index, Menopause-specific quality of life questionnaire (MENQOL), Menopause Rating Scale(MRS). Results: 1. The hot flush score, hot flush VAS, sweating VAS were significantly correlated with each other, but the Hot flush consistence time with no special relationship was found on Subjective measures of hot flush 2. The Kupperman's Index, Menopause-specific quality of life questionnaire (MENQOL) and Menopause Rating Scale(MRS) were significantly correlated with each other. 3. There was significant correlation between Subjective measures of hot flush and Menopause-specific quality of life questionnaire(MENQOL), Thus Menopausespecific quality of life questionnaire(MENQOL) is considered the most suitable on hot flush related research. Conclusions: There was significant correlation between Subjective measures of hot flush and Menopausal scale, thus the use of various indicators are needed for the assessment of climacteric symptoms.

• Journal of Oriental Medical Thermology
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• v.7 no.1
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• pp.37-43
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• 2009

Purpose: The purpose of this study is to identify the clinical effect of Red Ginseng in the treatment of postmenopausal hot flushes. Methods: We studied 49 women from 45 to 55 years old who complained hot flushes. We randomly divided women into two groups, We treated one group with red ginseng capsule, and treated another group with placebo for 2 months. patients recorded the frequency of the hot flush on an everyday basis. And we measured temperature of patient's face by DITI. Results: Red ginseng and Placebo treated group significantly decreased the frequency of the hot flush. After treatment, the temperature on the cheekbones who treated by red ginseng get lower than before treatment. But there is no statistically difference between red ginseng and placebo. Conclusion: This study shows that both red ginseng and placebo have remarkable effects on patients, but red ginseng is not better than placebo.