• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1B
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• pp.42-48
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• 2002

In broadband wireless networks, the effective meeting of the QoS guarantees may strongly depend on the Contention Resolution Algorithm used in the uplink contention period. The time it takes a station to transmit a successful request to the base station, or request delay, must be kept low even during periods of high contention. If a request suffers many collisions, it cannot rely on the preemptive scheduler to receive low access delays. However, the conventional collision resolution algorithm has a problem that all collided stations are treated equally regardless of their delay from previous contention periods. Some requests may have very long request delay caused by continuous collisions. In this paper, we propose an adaptive collision resolution algorithm for fast random access in broadband wireless networks. The design goal is to provide quick access to the request with a high number of collisions. To do this, the proposed algorithm separates the whole contention region into multiple sub regions and permits access through each sub region only to the requests with equal number of collisions. The sub region is adaptively created according to the feedback information of previous random access. By simulation, the proposed algorithm can improve the performance in terms of throughput, random delay and complementary distribution of random delay by its ability to isolate higher priorities from lower ones. We can notice the algorithm provides efficiency and random access delay in random access environment.

• International Journal of Costume and Fashion
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• v.7 no.1
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• pp.49-61
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• 2007

The subject of study concerns the color characteristics of clothing/accessories from �Chosun�a nd modern Korea. It particularly focuses on the colors of the �Jeogori? traditional jacket) which represents Korean traditional clothing. Color data were collected from 353 woman�s �Jegori�s from �Chosun�a nd modern Korea and divided into the predominant colors & sub colors, and analyzed with HV/C and PCCS. According to the analysis, the representative the predominant color of 'Chosun Jeogori' for woman is YR, Y and side one is R, YR. The p, dp, sf, ltg colors are frequently found and the freshness of most of them is medium or low which shows a calm-feeling. The p, and ltg tones are often found as a the predominant color and p, dp are also often found as a the side color. In the 'Chosun Jeogori' for woman, the predominant colors and the side colors spread in a similar frequency and most of them have medium or low freshness of the color that shows a calm-feeling. The side color is one of the R colors and it shows characteristics of traditional coloring such as �Jajoo Goreum? Among the �Jeogori�f or modern women, the R, YR, Y, and B colors are often used for the single-color �Jeogori? the Y, GY, N, G colors are for the colorful �Jeogori? The P, lt, and b tons of the color are often used for a single-color �Jeogori�a nd the p, lt, and W are for the colorful �Jeogori? For the colorful �Jeogori? the side color have a high freshness which shows that a strong image was used frequently as the dp, s, dk tons of the color were often used. According to an analysis of the coloring, the predominant color and the side color of �Chosun Jeogori�a re applied to create a harmony of analogy & contrast in one aspect of Moon & Spencer�s view. It is found that the predominant color and the side color are similar or contrasting in one view of the color harmony, except that the traditional the �Jeogori�i s colored by ideological and symbolic meanings. The predominant color and the side color of modern the �Jeogori�a re complementary colors which are applied to the indistinct relationship or contrasting harmony in one aspect of Moon & Spencer�s view of the color harmony. The characteristics of the color as above show that traditional the �Jeogori�r egards the side color as both the harmony of the colors in general and also of symbolic meaning, while modern the �Jeogori�f or woman has a tendency toward a cultural transition and is mixed with new colors focusing more on its the predominant color than on the general harmony and character of ideological & traditional coloring.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.10
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• pp.758-765
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• 2018

This paper presents a 24-GHz frequency-modulated continuous wave(FMCW) radar transceiver with two Rx and one Tx channels in 65-nm complementary metal-oxide-semiconductor(CMOS) process and implemented it on a radar system using the developed transceiver chip. The transceiver chip includes a $14{\times}$ frequency multiplier, low-noise amplifier, down-conversion mixer, and power amplifier(PA). The transmitter achieves >10 dBm output power from 23.8 to 24.36 GHz and the phase noise is -97.3 GHz/Hz at a 1-MHz offset. The receiver achieves 25.2 dB conversion gain and output $P_{1dB}$ of -31.7 dBm. The transceiver consumes 295 mW of power and occupies an area of $1.63{\times}1.6mm^2$. The radar system is fabricated on a low-loss Duroid printed circuit board(PCB) stacked on the low-cost FR4 PCBs. The chip and antenna are placed on the Duroid PCB with interconnects and bias, gain blocks and FMCW signal-generating circuitry are mounted on the FR4 PCB. The transmit antenna is a $4{\times}4$ patch array with 14.76 dBi gain and receiving antennas are two $4{\times}2$ patch antennas with a gain of 11.77 dBi. The operation of the radar is evaluated and confirmed by detecting the range and azimuthal angle of the corner reflectors.

• Korean Journal of Occupational Health Nursing
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• v.10 no.2
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• pp.142-152
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• 2001

This study examined all the papers published in the Journal of Occupational Health Nursing from 1991 to May 2000 based on an objective frame of evaluation. The purpose of study is to prospect the trend of occupational nursing research and to provide an optimal direction for future occupational nursing service. The results of total 94 studies were analyzed as follows. 1. The number of papers published in 1991-1992, 1993-1995, 1996-1997 was not significantly increased. However, the number of papers were obviously increased after 1998. 2. In the design of research, survey studies were definitely dominant. But, they are gradually decreasing and experimental studies are increasing. 3. In the fields of research, health problems, health risk factors and health awareness were higher than others. Occupational health nurse's task and job satisfaction were main areas of research until the middle of 1990's. However, after then, not only health problem, risk factor and awareness of health but also health promotion and preventive health behavior are increasing in the research areas. 4. The collaborative researches have gradually increased and the type of author has been varied. The number of researches completed by funds was undertaking only 3 among the total 94. 5. In the research analysis, except for case studies and literature studies, the research subjects have been shifted from the occupational health nurses to the industrial workers, and more diversified. The sample size has been enlarged and the major place of the study is industry. The questionnaire was used in many studies as instrument for data collection and measurement. But, complementary methods of diverse instruments have been increased. The method of data analysis has obviously showed some changes moving from descriptive statistics to inferential and advanced statistics. 6. The ways of nursing intervention have prominently diversified in experimental studies. The contents of case studies were mainly focused on the health management programs and activities in industry. The research concepts and the contents of literature study were also changed progressively in various way. Based on the above findings, conclusions are extended to the following discussion: Since the Korean Academic Society of Occupational Health Nursing was instituted in 1990, the researches of occupational health nursing have shown an acute methodological development in both quantity and quality. However, they were considered still in the lack of research verifying the effects of nursing intervention program. Also, the development of nursing intervention and nursing theory lacked. Therefore, more empirical researches are strongly needed to utilize the field of occupational health nursing in Korea Researchers are also encouraged to exert more efforts to get research funds.

• The Journal of Korean Medicine
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• v.28 no.4
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• pp.74-85
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• 2007

Objective : In this study we wanted to confirm if proper stimulation and de-Qi of traditional Korean medical acupuncture could increase hot flash relief efficacy. Design : A randomized controlled, single blind study. We used two modalities of acupuncture, one with optimal stimulation [Study group; Korean medical acupuncture (TKMA)] and one with minimal stimulation [Control group; Minimal acupuncture (MA)]. Same acupoints [PC6(內關), HT8(少府), HT7(神門), LI4(合谷), ST36(足三里), SP6(三陰交), Ren4(關元)] were used in both groups. Fifty-two patients were treated twice a week for 8 weeks, and follow up was done after 4 weeks from the last treatment. Patients were checked hot flash VAS (visual analog scale), frequency and duration every time they visited. Results : Hot flash relief efficacy by 100mm hot flash VAS was obvious in both groups. Hot flash VAS scores of study group were smaller than the scores of control group at the early stage (3rd, $4^{th}$ and $8^{th}$ visit), but there wasn't a remarkable difference between study and control group at the end of the trial. Besides, diminution of hot flash VAS was faster and more even in the study group than control group by visualization using 'Box plot'. We compared frequency and duration of hot flash, 100mm sweating, palpitation, sleep disturbance VAS, and Kupperman Index, MENQOL, Patient's global assessment score. Both groups showed definite decrease from the baseline, but the difference was not statistically significant. There wasn't any adverse event. Hot flash relief efficacy was kept in most patients after 4 weeks' follow-up. Conclusion : Acupoint combination by Traditional Korean medical theory is effective on hot flashes and hot flash relief efficacy was faster and more even in optimal stimulation than minimal stimulation.

• Journal of Hospice and Palliative Care
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• v.19 no.4
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• pp.296-302
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• 2016

Purpose: This study examined the effectiveness of a hand massage combined with analgesics on pain control in hospice patients with terminal cancer. Methods: This study is a quasi-experimental study with a single group time series design. The study included 25 terminal cancer patients who were admitted to a hospice ward. Each patient's pain level was measured after analgesics use only (control group). When patients complained of pain again, the pain level was assessed after administering a combination of hand massage and analgesics (experimental group). As for the experimental treatment, the participants were provided with oil hand massage on each hand for 5 minutes. Results: The experimental group and the control group showed no significant differences in the changes of pain score (F=0.74, P=0.3939). Conclusion: Although the pain level of the experimental group did not significantly improve compared with the control group, their pain levels tended to be low to begin with. Thus, a complementary utility value of hand massage cannot be completely excluded in terminal cancer patients. Since the pain level significantly changed according to the dosage of analgesic, nurses need more education and research on analgesic drug therapy for terminal cancer patients.

• Journal of Distribution Science
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• v.17 no.3
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• pp.107-116
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• 2019

Purpose - Why, why is it difficult to predict the appropriateness of self-employment, and what are the countermeasures and policy proposals to overcome. This study intends to further develop the field of statistical variables. It is necessary to overcome the limitation of existing proper scale research in Korea. We need to find statistical variables that can determine the appropriateness of self-employment in Korea. These efforts will be helpful in evaluating OECD countries and statistics and developing domestic economic indicators. Research design, data, and methodology - It is the discovery of statistical indicators and complementary indicators that have not been revealed in previous studies. Therefore, we sought to find new statistical parameters based on the statistics of the Korea National Statistical Office, the Bank of Korea, and overseas OECD statistics. (Proper Size of Adequacy) is defined as the specific gravity or number of the self-employed in Korea, which is shown as "Out Put" by statistical analysis of STATA panel statistical data. It is possible to further develop variables such as gross domestic product, gross national product, economic growth rate, unemployment rate, income tax rate, consumer price, tax level, exports, import amount, bill default I want to dig. Results - In addition to expanding economic indicators that can be explained by self-employment determinants, we have developed a variety of methods such as linear and non-linear (U-shaped, inverted U-shaped). It is the improvement of the self-employment determinants and the analysis method to estimate the appropriate scale. Conclusions - The proposed contents are reflected in self - employment appropriateness evaluation data and hope to help the government to select the policy support and to evaluate the government business after the policy support. These efforts are expected to be of great help to operators operating their own businesses, and to government and related institutional practitioners who support them. In this way, self-employment will be created in accordance with the Korean situation, where the happy life of all the people becomes the premise and the inclusive economic activities are guaranteed. It will improve the method of analyzing proper scale of small business owners and self-employed in Korea.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.199-208
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• 2008

Lately, since Complementary Metal Oxide Semiconductor(CMOS) image sensor system has low power, low cost and been miniaturized, hardware and applied software studies using these strengths are being carrying on actively. However, the products equipped with CMOS image sensor based polling method yet has several problems in degree of completeness of applied software and firmware, compared with hardware’s. CMOS image sensor system has an ineffective synchronous problem due to superfluous message exchange. Also when a sending of data is delayed continually, overhead of re-sending is large. So because of these, it has a problem in structural stability according to Polling Method. In this study, polling cycle was subdivided in high-speed synchronization method of firmware -based through MCU and synchronization method of Stepwise was proposed. Also, re-connection and data sending were advanced more efficiently by using interrupt way. In conclusion, the proposed method showed more than 20 times better performance in synchronization time and error connection. Also, a board was created by using C328R board of CMOS image sensor-based and ATmega128L which has low power, MCU and camera modules of proposed firmware were compared with provided software and analyzed in synchronization time and error connection.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.1
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• pp.50-55
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• 2008

In this paper, New LC VCO with $8{\sim}10.9$ GHz Band has been designed using commercial $0.35-{\mu}m$ CMOS technology. This proposed circuit is consisted of the parallel construction of the typical NMOS and PMOS cross-coupled pair which is based on the LC tank, MOS cross-coupled pair which has same tail current of complementary NMOS and PMOS, and output buffer. The designed LC VCO, which is according to proposed structure in this paper, takes a 29% improvement of the wide tuning range as 8 GHz to 10.9 GHz, and a 6.48mW of low power dissipation. Its core size is $270{\mu}m{\times}340{\mu}m$ and its phase noise is as -117dBc Hz and -137dBc Hz at 1-MHz and 10-MHz offset, respectively. FOM of the new proposed LC VCO gets -189dBc/Hz at a 1-MHz offset from a 10GHz center frequency. This design is very useful for the 10Gb/s clock generator and data recovery integrated circuit(IC) and SONET communication applications.

• Journal of the Ergonomics Society of Korea
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• v.33 no.1
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• pp.39-48
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• 2014

Objective: This entire study has two parts. Study I aimed to develop a psychological assessment scale and the study II aimed to investigate the effects of LFN (low frequency noise) on the psychological responses in humans, using the scale developed in the study I. Background: LFN is known to have a negative impact on the functioning of humans. The negative impact of LFN can be categorized into two major areas of functioning of humans, physiological and psychological areas of functioning. The physiological impact can cause abnormalities in threshold, balancing and/or vestibular system, cardiovascular system and, hormone changes. Psychological functioning includes cognition, communication, mental health, and annoyance. Method: 182 college students participated in the study I in development of a psychological assessment scale and 42 paid volunteers participated in the study II to measure psychological responses. The LFN stimuli consisted of 12 different pure tones and 12 different 1 octave-band white noises and each stimulus had 4 different frequencies and 3 different sounds pressure levels. Results: We developed the psychological assessment scale consisting of 17 items with 3 dimensions of psychological responses (i.e., perceived physical, perceived physiological, and emotional responses). The main findings of LFN on the responses were as follows: 1. Perceived psychological responses showed a linear relation with SPL (sound pressure level), that is the higher the SPL is, the higher the negative psychological responses were. 2. Psychological responses showed quadric relations with SPL in general. 3. More negative responses at 31.5Hz LFN than those of 63 and 125Hz were reported, which is deemed to be caused by perceived vibration by 31.5Hz. 'Perceived vibration' at 31.5Hz than those of other frequencies of LFN is deemed to have amplified the negative psychological response. Consequently there found different effects of low frequency noise with different frequencies and intensity (SPL) on multiple psychological responses. Conclusion: Three dimensions of psychological responses drawn in regard to this study differed from others in the frequencies and SLP of LFN. Negative psychological responses are deemed to be differently affected by the frequency, SPL of the LFN and 'feel vibration' induced by the LFN. Application: The psychological scale from our study can be applied in quantitative psychological measurement of LFN at home or industrial environment. In addition, it can also help design systems to block LFN to provide optimal conditions if used the study outcome, .i.e., the relations between physical and psychological responses of LFN.