• Journal of Communications and Networks
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• v.8 no.4
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• pp.451-460
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• 2006

Since low earth orbit (LEO) satellite constellations have important advantages over geosynchronous earth orbit (GEO) systems such as low propagation delay, low power requirements, and more efficient spectrum allocation due to frequency reuse between satellites and spotbeams, they are considered to be used to complement the existing terrestrial fixed and wireless networks in the evolving global mobile network. However, one of the major problems with LEO satellites is their higher speed relative to the terrestrial mobile terminals, which move at lower speeds but at more random directions. Therefore, handover management in LEO satellite networks becomes a very challenging task for supporting global mobile communication. Efficient and accurate methods are needed for LEO satellite handovers between the moving footprints. In this paper, we propose a new seamless handover management scheme for LEO satellites (SeaHO-LEO), which utilizes the handover management schemes aiming at decreasing latency, data loss, and handover blocking probability. We also present another interesting handover management model called satellite mobility pattern based handover management in LEO satellites (PatHO-LEO) which takes mobility pattern of both satellites and mobile terminals into account to minimize the handover messaging traffic. This is achieved by the newly introduced billboard manager which is used for location updates of mobile users and satellites. The billboard manager makes the proposed handover model much more flexible and easier than the current solutions, since it is a central server and supports the management of the whole system. To show the performance of the proposed algorithms, we run an extensive set of simulations both for the proposed algorithms and well known handover management methods as a baseline model. The simulation results show that the proposed algorithms are very promising for seamless handover in LEO satellites.

• Journal of the Korean Society of Costume
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• v.29
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• pp.23-38
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• 1996

The purpose of this study was to analyze the characteristics of the Minimal Art represented in the second half 20th century fashion. All the mode of dress worn this century have developed from the stimulus of a chang-ing society fired by new discoveries and a zest for the new and different. It would appear that even more dramatic changes will soon occur in our clothing styles the effects of which will be farreaching. Many of today's styles intended to dress our psyche rather than our bodies and this if fully understood by the new designers whose influ-ence will become increasingly more potent as we approach the new century. The highly developed material civilization resulted in human alienations environmental distruption, l By this fact human being of the 20th century was to overcome social com-plexity. Accordingly their search for simplicity was interested in the 60's style. Especially the formativeness of the 60s style was repre-sented in the second half 20th century fashion. In this paper it was focused that how the characteristics of the Minimal Art was expressed in the second half 20th century fashion. minimalism was a quest for basic elements repesenting the fundamental esthetic values of art. without regard to issues of content. At its most extreme it reduced art not ot an eter-nal essence but to an arid simplicity. "Primary Structure" the most suitable name suggested for this type conveys its two salient characteristics : extreme simplicity of shapes and a kinship with architecture. minimalist works are charcterized by huge dimensions coldness and absolute aesthetic neutrality. minimalist artists ambition is to de-fine through the most rudimentary materials such as plywood galvanized iron aluminum plastic and wood a new order of the space. The environment is just as important as the object itself. Similary the use of new tough materials. such as vinyl metal and plastic at late half of the 20th century fashion related to the formativeness of the Minimal Art. And the style of 20th fashion was holded the internal meanings in common the formativeness of the Minimal Aet thorough the various texture pat-tern silhouette etc.uette etc.

• Journal of muscle and joint health
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• v.6 no.2
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• pp.278-294
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• 1999

The PACE (People nth Arthritis Can Exercise) is an exercise program developed by the Arthritis Foundation to improve muscle strength and joint flexibility for patients with arthritis. The purpose of this study was to explore the effects of PACE program on self-efficacy, pain, and joint function in the Korean immigrant elderly. The PACE program was held twice a week for 6 weeks for Korean immigrant elderly who had osteoarthritis. Twenty four subjects completed the program, who were recruited in two places : 10 elderly in a senior residential apartment, and 14 elderly in a senior center supported by Congregated Meal Program for Korean Elderly. Self-efficacy(Sherer et al., 1982), pain severity(by using Visual Analogue Scale), and number of painful joints were measured before and after the PACE program. To examine the joint flexibility and strengthening, the followings were measured : the extent of the upward arm reach in both sides(flexibility of shoulder), the ability to touch fingertips of the both hands in back pat and rub(flexibility of arm), the degree of range of motion(ROM) of both ankles in their dorsiflexion(flexibility of ankle) and plantarflexion with standing with toe(strengthening of ankle), and the degree of knee extension. Wilcoxon signed rank test was used for data analysis and the significance of the differences in the variables was examined to compare the data obtained before and after the PACE program. After the PACE, followings were found : 1. Self-efficacy was significantly increased. 2. Pain severity and number of painful Joints was significantly decreased. 3. The flexibility of both shoulders and arms were significantly improved, but the flexibility of knee was not changed. 4. The flexibility and strengthening of both ankle was significantly improved. In conclusion, PACE was clearly proved to be an effective exercise program to promote self-efficacy, to reduce pain, and to enhance joint function in the elderly with osteoarthritis. It is suggested that the PACE program should be recommended as one of the useful and appropriate nursing interventions for elderly with osteoarthritis.

• 대한근관절건강학회:학술대회논문집
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• 2001.04a
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• pp.179-190
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• 2001

The purpose of this study was to explore the effects of GEAP on pain, joint function, activities of daily living(ADL) and fatigue in chronic arthritis patients. The GEAP was held twice a week for 6 weeks for chronic arthritis patients at one university hospital in Seoul, Korea. Thirty four subjects completed the program, who were recruited at four times from September, 1999 to September, 2000. The effect of GEAP were evaluated as follows: Pain severity and number of painful joints ADL, fatigue were measured before and after the GEAP. In order to examine the joint flexibility and strengthening, the followings were measured: the extent of the upward arm reach in both sides(flexibility of shoulder), the ability to touch fingertips of the both hands in back pat and rub(flexibility of arm), the degree of range of motion (ROM) of both ankles in their dorsiflexion(flexibility of ankle) and plantarflexion with standing with toe(strengthening of ankle), and the degree of knee extension, and the grip strength. Paired t-test and Wilcoxon signed rank test were used for data analysis and the significance of the differences in the variables was examined to compare the data obtained before and after the GEAP. After the GEAP, followings were found: 1. Pain severity and number of painful joints was significantly decreased. 2. The flexibility of both shoulders and arms, knee, both ankle were significantly improved. 3. The strengthening of both arms was significantly improved, but the strengthening of ankle was not changed. 4. ADL was significantly increased. 5. Fatigue was significantly decreased. In conclusion, GEAP used in this study was clearly proved to be an effective exercise program to reduce pain and fatigue, to enhance joint function and ADL in people with chronic arthritis. It is suggested that the GEAP should be recommended as one of the useful and appropriate nursing interventions for chronic arthritis patients.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.221-237
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• 1991

This study was conducted to evaluate the accuracy and the precision of asbestos counting data produced by the Division of Industrial Health, School of Public Health, Seoul National Universitys (SNU). The study was performed from July 18 to October 4, 1991, and the results are summarized as follows. 1. Intracounter Relative Standard Deviations (Sr) in the category of 5-50.5 fibers as total fibers counted ranged from 0.27 to 0.37, which were greater than 0.10-0.17 which were reported by the NIOSH. The reasons are supposed to be as follows. First, inexperience of counters in asbestos fiber counting was considered to be a main reason. Second, poor quality of samples due to sampling and mounting error increased variation of counting. Third, fiber density of many samples were less than $100fibers/mm^2$. But Intracounter Relative Standard Deviations (Sr) in samples with >50.5 fibers ranged from 0.l6 to 0.20, approaching the value 01 NIOSH. 2. Intralaboratory Relative Standard Deviations (Sr) in categories of 5-20.5, >20.5-50.5 and >50.5 fibers were 0.54, 0.37 and 0.26, respectively. Intralaboratory Sr in samples with fiber density greater than $100fibers/mm^2$ was 0.26. This was similar to the values reported by other foreign experienced laboratories. 3. Comparing results of three counters, Counter C, a beginner, overestimated asbestos fiber concentrations. 4. Since our SNU laboratory has participated in two quality control programs, IOMA-F.R.I.C.A., U.K. and NIOSH PAT Program, U.S.A., this laboratory has been evaluated as " Rating 1" and "Proficient" laboratory, by IOM and NIOSH, respectively.

• Toxicological Research
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• v.17 no.1
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• pp.41-47
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• 2001

In order to test the effects of hyperbaric oxygen (HBO) and $\alpha$-tocopherol on full-thickness skin grafts in rats, we peeformed full-thickness skin grafts bilaterally on rats. After surgery, we analyzed the tissue-concentrations of superoxide dismutase (SOD), catalase, and glutathione peroxidase(GPx)/reductase(GPr) on days 0, 2, 4, 7, 10, 14, 21 and 28. The four groups had similar patterns of change in SOD, catalase, GPx and GPr values. SOD increased initially, and was significantly increased at day 7, returning to the preoperative activity level on day 14 (control, HBO, and $\alpha$-tocopherol treated alone) and 28 (HBO plus $\alpha$-tocopherol). Catalase had a similar pattern of change as the SOD enzyme activity, except for the surgical control on day 2. Glutathione peroxidase/reductase activity in the four groups had a similar pat-tern of enzyme activity, with a significant increase from preoperative level on day 4, peaking during days 7 to 10, and returning to preoperative level on day 21(surgical control, HBO, and $\alpha$-tocopherol-treated alone) and 28 (HBO plus $\alpha$-tocopherol treated group). Hence, the clinical use of HBO and $\alpha$-tocopherol mixture can be recommended as an adjunctive treatment for free skin grafts in rats. But, the antioxidant used, its dose, and the timing of its administration, as well as, the exposure time and the pressure of HBO, should be the subject of further research.

• Journal of Chest Surgery
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• v.51 no.3
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• pp.172-179
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• 2018

Background: This study aimed to compare preliminary data on the outcomes of sutureless aortic valve replacement (SU-AVR) with those of aortic valve replacement (AVR). Methods: We conducted a retrospective study of SU-AVR in moderate- to high-risk patients from 2013 to 2016. Matching was performed at a 1:1 ratio using the Society of Thoracic Surgeons predicted risk of mortality score with sex and age. The primary outcome was 30-day mortality. The secondary outcomes were operative outcomes and complications. Results: A total of 277 patients were studied. Ten patients (50% males; median age, 81.5 years) underwent SU-AVR. Postoperative echocardiography showed impressive outcomes in the SU-AVR group. The 30-day mortality was 10% in both groups. In our study, the patients in the SU-AVR group developed postoperative thrombocytopenia. Platelet counts decreased from $225{\times}10^3/{\mu}L$ preoperatively to 94.5, 54.5, and $50.1{\times}10^3/{\mu}L$ on postoperative days 1, 2, and 3, respectively, showing significant differences compared with the AVR group (p=0.04, p=0.16, and p=0.20, respectively). The median amount of platelet transfusion was higher in the AVR group (12.5 vs. 0 units, p=0.052). Conclusion: There was no difference in the 30-day mortality of moderate-to high-risk patients depending on whether they underwent SU-AVR or AVR. Although SU-AVR is associated with favorable cardiopulmonary bypass and cross-clamp times, it may be associated with postoperative thrombocytopenia.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.745-753
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• 2016

This paper presents a fully synthesizable low power interconnect bus for millimeter-scale wireless sensor nodes. A segmented ring bus topology minimizes the required chip real estate with low input/output pad count for ultra-small form factors. By avoiding the conventional open drain-based solution, the bus can be fully synthesizable. Low power is achieved by obviating a need for local oscillators in member nodes. Also, aggressive power gating allows low-power standby mode with only 53 gates powered on. An integrated wakeup scheme is compatible with a power management unit that has nW standby mode. A 3-module system including the bus is fabricated in a 180 nm process. The entire system consumes 8 nW in standby mode, and the bus achieves 17.5 pJ/bit/chip.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.941-946
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• 2013

Objective: The nucleotide excision repair (NER) and base excision repair (BER) pathways, two DNA repair pathways, are related to platinum resistance in cancer treatment. In this paper, we studied the association between single nucleotide polymorphisms (SNPs) of involved genes and response to platinum-based chemotherapy in epithelial ovarian cancer. Method: Eight SNPs in XRCC1 (BER), XPC and XPD (NER) were assessed in 213 patients with epithelial ovarian cancer using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) techniques. Results: The median progression-free survival (PFS) of patients carrying the Lys/Lys and Lys/Gln+Gln/Gln genotype of the XPC Lys/Gln polymorphism were 25 and 12 months, respectively (P=0.039); and the mean overall survival (OS) of patients was 31.1 and 27.8 months, respectively (P=0.048). Cox's multivariate analysis suggested that patients with epithelial ovarian cancer with the Gln allele had an increased risk of death (HR=1.75; 95% CI=1.06-2.91) compared to those with the Lys/Lys genotype. There are no associations between the XPC PAT+/-, XRCC1 Arg194Trp, Arg280His, Arg399Gln, and XPD Asp312Asn, Lys751Gln polymorphisms and the survival of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy. Conclusion: Our results indicated that the XPC Lys939Gln polymorphism may correlate with clinical outcome of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy in Northern China.

• Journal of the Korean Society of Costume
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• v.33
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• pp.255-267
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• 1997

The objective of this study was to examine how clothing pattern preferences vary accod-ing to sex role identity gender and age. Questionnaire of shirt pattern prefere-nces and short form Bem Sex Role Inventory was administered to 627 men and women(10's to 40's) in Kwangju City. Sex role identity was classified in androgynous masculine feminine and undifferentiated type. 1. The men liked thick horizon thin check and plaid pattern better than the women while the women small flower one. 2. The 10's liked thick horizon thin check and plaid pattern better than the women while the women small flower one. 2, The 10's liked thick horizon pattern better than the others, 3. On the interaction effect according to gender and age the women in their 30's liked polka dots pattern better than the men while the women in their 10's and 20's liked plaid pattern better than the women in their 30's and 40's 4. On the interaction effect according to sex role identity and age the masculine type in their 30's and 40's disliked small flower pat-tern while the feminine type in their 30's and 40's liked it. The women in their 30's liked small flower pattern while the 10's disliked it more than the others. 5. The androgynous type liked thin check and plaid pattern better than the others. The present findings provide that sex role identity gender and age influenced clothing pattern preferences. Gender and age had sig-nificant interaction effects on the preferences. The traditional connections between sex role identity and flower pattern perferences were confirmed only in the 30's and 40's.