• Tuberculosis and Respiratory Diseases
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• v.47 no.3
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• pp.374-382
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• 1999

Background: The aim of this study was to investigate etiologic factor, treatment, prognosis of spontaneous pneumothorax (SP). Material and Methods: The medical records of 225 cases of SP experienced at Kyungpook University Hospital from Jan. 1996 to Dec. 1997 were retrospectively analyzed. Results: The patients were 128 primary SP and 97 secondary SP. The mean age was $30{\pm}15.5$ years in primary SP and $51{\pm}7.4$ years in secondary SP. The ratio of male to female was 8:1 in primary SP and 5.5:1 in secondary SP. Smoker was more common in seconday SP (71.1 %) than primary SP (34.4%). About 70% of patients with primary and secondary SP was underweighted. The previous history of SP was present in 28.9% and 25.8% of primary and secondary SP, respectively. The main underlying lung diseases in secondary SP were inactive tuberculosis (68%), active tuberculosis (12.4%) and COPD (11.3%). Tube thoracostomy was performed in 96.8% and 97.9% of primary and secondary SP, respectively. The duration of chest tube insertion was longer in seconday SP ($18.2{\pm}19.59$ days) than primary SP ($7.5{\pm}6.57$ days). The open thoracotomy were performed in 22.7% and 10.3% of primary and secondary SP, respectively. The most com- mon indication of open thoracotomy was recurrence in primary SP and persistent air leak in secondary SP. During following-up of $17{\pm}7.8$ months, the recurrence rate in patients with conservative treatment was 16.5% and 11.8% of primary and secondary SP, respectively. The recurrence was most common within 1 month after discharge. Conclusion: Greater attention and research about SP are necessary for more efficient patient care.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.25-32
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• 2010

This paper evaluates the outage probability of cognitive relay networks with cooperation between secondary users based on the underlay approach, when multiple primary receivers coexist with secondary users. Using an appropriate relay selection criterion in cognitive radio networks, we derive the outage probability of secondary user. It is shown that the outage probability increases as the number of primary receivers increases and we quantify the increase. Through the simulation results, we verify that the performance of relaying transmission is varied more sensitively compared to that of direct transmission as the number of primary receivers increases. In addition, the relaying transmission can be less efficient than the direct transmission when multiple primary receiver exist but it can be more efficient than the direct transmission by increasing the relay selection diversity.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.552-557
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• 2004

Mobile Ad Hoc Network (MANET) is a network architecture, which has no backbone network and is deployed temporarily and rapidly in emergency or war without fixed mobile infrastructures. All communications between network entities are carried in ad-hoc networks over the wireless medium. Due to the radio communications being extremely vulnerable to propagation impairments, connectivity between network nodes is not guaranteed. Therefore, previously developed routing algorithms in wired networks cannot be used. And many new algorithms have been undergone. This study proposes the secondary leader approach to the cluster based routing protocol(CBRP). In case, the primary leader becomes abnormal status so that the primary leader cannot participate the communications between network entities, the secondary leader immediately replaces the primary header without selecting process of the new primary leader. The performances of proposed algorithm ACBRP(Advanced Cluster. Based Routing Protocol;CBRP using secondary leader) are compared with CBRP and results are presented in order to show the effectiveness of the algorithm.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.102-109
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• 2022

In order to explore the characteristics that are more suitable for the physical and mental development of young people, enrich the existing martial arts teaching material system. Through the literature method, experimental method, questionnaire method and other research methods, the teaching comparison experiment of martial arts textbooks in primary and secondary schools was carried out, and the attitudes of martial arts courses at different ages in primary and secondary schools were analyzed. For different types of martial arts teaching materials, primary school students are more fond of them than junior high school students, and students of different ages also have different degrees of love for the four types of martial arts teaching materials, pointing out that it is necessary to carry out the reform of martial arts teaching materials as soon as possible, improve the difficulty, teach martial arts skills and knowledge in the combination of attack and defense, and reduce the trend of gymnastics; adjust and improve the periodicity, pertinence and diversity of martial arts teaching materials; mobilize students' enthusiasm for learning, cultivate students' interest in martial arts, and promote the inheritance of martial arts In the process of martial arts teaching, students' sense of identification with traditional Chinese culture is enhanced, and cultural self-confidence is enhanced.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.10
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• pp.2455-2472
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• 2012

Although underlay spectrum sharing has been shown as a promising technique to promote the spectrum utilization in cognitive radio networks (CRNs), it may suffer bad secondary performance due to the strict power constraints imposed at secondary systems and the interference from primary systems. In this paper, we propose a two-phase based cooperative transmission protocol with the interference cancellation (IC) and best-relay selection to improve the secondary performance in underlay models under stringent power constraints while ensuring the primary quality-of-service (QoS). In the proposed protocol, IC is employed at both the secondary relays and the secondary destination, where the IC-based best-relay selection and cooperative relaying schemes are well developed to reduce the interference from primary systems. The closed-form expression of secondary outage probability is derived for the proposed protocol over Rayleigh fading channels. Simulation results show that, with a guaranteed primary outage probability, the proposed protocol can achieve not only lower secondary outage probability but also higher secondary diversity order than the traditional underlay case.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.1-12
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• 2006

This study conducted RIII reflex measurement to examine degree of pain depending on polarity of high voltage pulsed current of primary and secondary hyperalgesia site in hyperalgesia rat by local thermal injury. Hind paw which was injury site was taken as primary hyperalgeisa site, sole which was injury adjacent site was taken as secondary hyperalgesia site, and mechanical pain threshold, thermal pain threshold and root mean square of RIII reflex were measured. This study was conducted with control group I of hyperalgesia rat at hind paw by thermal injury and experimental groups divided into cathodal high voltage treatment group II, anodal high voltage treatment group III and alternate high voltage treatment group IV, applied active electrode of high voltage pulsed current to hind paw directly, placed reference electrode on the sole of injury adjacent site and applied pulse frequency. It measured RIII reflex and obtained the following results: Root mean square of RIII reflex at primary hyperalgeisa site was significantly reduced in group II after 2 days of hyperalgesia. Group II showed significant decrease after 5 and 6 days of hyperalgesia. Root mean square of RIII reflex at secondary hyperalgesia site showed significant reduction in group II after 6 days of hyperalgesia. Consequently it was found that application of high voltage pulsed current of hyperalgesia site reduced RIII reflex at primary hyperalgeisa site and secondary hyperalgesia site by electrical stimuli. Effects by polarity of high voltage pulsed current showed the greatest reduction of pain threshold when cathodal active electrode was used.

• Hwankyungkyoyuk
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• v.2 no.1
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• pp.5-33
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• 1991

The purpose of the study was to investigate attitudes toward to, values and expectations of environmental education of Korean students and teachers and to provide basic data and reference materials needed to development of environmental education curricula for primary and secondary schools. A review of the related literature, a series of conferences with teachers and specialists in environmental education and environmental sciences. and questionnaire survey were methods employed in this study. Survey question were developed to explore attitude and responses of primary and secondary school students and teachers on various types of issues and problems of environmental education at personal level as well as on their future prospects attitudes values and expectations with which had been dealt in this study were categorized into personal feeling on environmental issues and problems at both national and regional levels issues and problems of current environmental education pre service and in service training of teachers for environmental education instruction and so on. The sample population for the survey was selected by using the stratified cluster and random sampling techniques with respect to regional area, school level, sex and grade, The subjects used in this study were 1,633 students and 385 teachers of primary and secondary schools across the country. The results of the survey were summed up and recommendations to be considered in the revision of sixth national curricula for primary and secondary schools were also suggested.

• Development and Reproduction
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• v.19 no.1
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• pp.1-10
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• 2015

The purpose of the present study was to examine the seminiferous epithelium cycle of Bombina orientalis using a light microscope. The cycle was divided into a total of 10 stages, according to the morphological characteristics of the cells. The spermatogenetic cells included primary spermatogonia, secondary spermatogonia, primary spermatocytes, secondary spermatocytes, spermatid and sperm. At stage I, the primary spermatogonia was located closer to basal lamina of the seminiferous tubule without spermatocyst formations. Especially at the stage II, the secondary spermatogonia were located in the spermatocyst. The primary and secondary spermatocytes were found from stages III to VI. The secondary spermatocytes were smaller in size than the primary spermatocytes, but they had thicker nucleoplasm and smaller nuclei. The round-shaped, early sperm cells were formed in stage VII, and further divided at stage VIII to have more concentrated nucleoplasm before division to matured sperm cells. At stage X, the matured sperm cells emerged from the spermatocyst. Considering the above results, this study presented the special characteristics in the generation and type of sperm formation. The germ cell formation occurred in various stages, like the perspectives of Franca et al (1999), ultimately, providing taxonomically useful information.

• Journal for History of Mathematics
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• v.25 no.3
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• pp.77-95
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• 2012

The purpose of this study is to draw implication for the teacher education program in association with creativity through analysing teaching behavior for fostering creativity of the mathematics teachers at the primary and secondary schools. In order to do so, a survey was performed by sampling primary, middle, and high school teachers. According to the results, there is significant difference in teachers' behavior for fostering creativity in the perspective of school classification (primary and secondary school), but not gender, region, and career of teachers. In other words, there is significant difference in teaching behaviors for fostering creativity between primary and secondary school teachers, herein the score of teaching behavior of former is higher than latter. Furthermore, the result of teachers' recognition survey on the possibility of fostering students' creativity via education shows that the teachers of primary schools are more relatively positive than those of secondary schools on the matter.

• Journal of Chest Surgery
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• v.56 no.4
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• pp.264-271
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• 2023

Background: The optimal management strategy for aortoiliac occlusive disease (AIOD) remains debatable. This study compared early and late outcomes between direct surgical bypass and kissing stents for AIOD treatment. Methods: We retrospectively reviewed data, including age, sex, risk factors, comorbidities, symptoms, TransAtlantic Inter-Society Consensus (TASC) II classification, operation time, perioperative complications, in-hospital mortality, and length of hospital stay, from a cohort of 46 patients treated for AIOD (24 with kissing stents and 22 with direct surgical bypass) at Pusan National University Hostpital from January 2007 to December 2016. The primary, assisted primary, and secondary patency rates in both groups were compared. Results: The hospital stay (direct surgical bypass vs. kissing stents: 16.36±5.19 days vs. 9.08±10.88 days, p=0.007) and operation time (direct surgical bypass vs. kissing stents: 316.09±141.78 minutes vs. 99.54±37.95 minutes, p<0.001) were significantly shorter for kissing stents. Kaplan-Meier analysis revealed that the primary, assisted primary, and secondary patency rates in the direct surgical bypass group were 95.5%, 95.5%, and 95.5%, respectively, at 1 year; 86.4%, 86.4%, and 95.5% at 3 years; and 77.3%, 77.3%, and 95.5% at 5 years. The primary, assisted primary, and secondary patency rates in the kissing stent group were 100.0%, 100.0%, and 100.0%, respectively, at 1 year; 95.8%, 95.8%, and 100.0% at 3 years; and 95.8%, 95.8%, and 100.0% at 5 years. Conclusion: Except for special cases wherein endovascular revascularization is difficult, kissing stents are more advantageous for TASC II C and D lesions.