• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.2889-2909
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• 2017

Wireless sensor networks (WSNs) have attracted lots of attention in recent years due to their potential for various applications. In this paper, we seek how to efficiently deploy relay nodes into traditional static WSNs with constrained locations, aiming to satisfy specific requirements of the industry, such as average energy consumption and average network reliability. This constrained relay node deployment problem (CRNDP) is known as NP-hard optimization problem in the literature. We consider addressing this multi-objective (MO) optimization problem with an improved Artificial Bee Colony (ABC) algorithm with a linear local search (MOABCLLS), which is an extension of an improved ABC and applies two strategies of MO optimization. In order to verify the effectiveness of the MOABCLLS, two versions of MO ABC, two additional standard genetic algorithms, NSGA-II and SPEA2, and two different MO trajectory algorithms are included for comparison. We employ these metaheuristics on a test data set obtained from the literature. For an in-depth analysis of the behavior of the MOABCLLS compared to traditional methodologies, a statistical procedure is utilized to analyze the results. After studying the results, it is concluded that constrained relay node deployment using the MOABCLLS outperforms the performance of the other algorithms, based on two MO quality metrics: hypervolume and coverage of two sets.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.1
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• pp.25-36
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• 2021

The honey bee has a crucial ecological status for maintaining the natural ecology system. Pollination mediations by honey bees are recognized as an efficient way to enhance the quality of biological diversity and green areas in the nature and the urban ecological system. However, the population of bee around the world is decreasing and we do not know exactly how bees react to the physical environment in the urban area. This study is a basic research for the improvement of pollination services in the Korean urban ecological system. It aims to induce and review environmental variables which have high relations with the activities of pollination mediation insects in the urban area. The study established a Maxent model using five urban environmental variables that reflect the ecology of Bombus ignitus and the place information where Bombus ignitus appears in 18 spots of Seoul city, and compared with previous research results on Apis millifera. Bombus ignitus preferred places with more natural environments such as mountain forest areas and vicinities of streams. They preferred Stratified Tree Area the most among the vegetation types existing in the urban area. Comparing chicken models, both species saw their response value drop as the building coverage rose. In the case of Apis millifera and Bombus ignitus variables, the response value of both species was high in 10 out of 20 types. The result of this study is expected to provide basic information for improving the pollination services in the Korean urban area and to be utilized as the basic materials for the future urban planning.

• Korean Journal of Materials Research
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• v.9 no.8
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• pp.825-830
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• 1999

Characteristics of SiOF films deposited by a FTES/$O_2$-plasma enhanced chemical vapor deposition method have been investigated using Fourier transform infrared spectroscopy, X-ray photoelectro spectroscopy, and ellipsometry. Electrical properties such as dielectric constant, dielectric breakdown and leakage current density are investigated using C-V and I-V measurements with MIS(Au/SiOF/p-Si) capacitor structure. Stepcoverage of the films have been also characterized using scanning electron microscopy and ellipsometry. A high quality SiOF film was formed on that the flow rates of FTES and $O_2$were 300sccm, respectively. The dielectric constant of the deposited SiOF film was about 3.1. This value is lower than that of the oxide films obtained using other method. The dielectric breakdown field and leakage current are more than 10MV/cm and about $8[\times}10^{9}A/\textrm{cm}^2$, respectively. The deposited SiOF film with thickness as $2500{\AA}$ on the $0.3{\mu}{\textrm}{m}$ metal pattern shows a high step-coverage without a void.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2141-2146
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• 2013

Cervical cancer is the third most common form of cancer that strikes Malaysian women. The National Cancer Registry in 2006 and 2007 reported that the age standardized incidence (ASR) of cervical cancer was 12.2 and 7.8 per 100,000 women, respectively. The cumulative risk of developing cervical cancer for a Malaysian woman is 0.9 for 74 years. Among all ethnic groups, the Chinese experienced the highest incidence rate in 2006, followed by Indians and Malays. The percentage cervical cancer detected at stage I and II was 55% (stage I: 21.0%, stage II: 34.0%, stage III: 26.0% and stage IV: 19.0%). Data from Ministry of Health Malaysia (2006) showed a 58.9% estimated coverage of pap smear screening conducted among those aged 30-49 years. Only a small percentage of women aged 50-59 and 50-65 years old were screened, 14% and 13.8% coverage, respectively. Incidence of cervical cancer was highest (71.6%) among those in the 60-65 age group (MOH, 2003). Currently, there is no organized population-based screening program available for the whole of Malaysia. A pilot project was initiated in 2006, to move from opportunistic cervical screening of women who attend antenatal and postnatal visits to a population based approach to be able to monitor the women through the screening pathway and encourage women at highest risk to be screened. The project was modelled on the screening program in Australia with some modifications to suit the Malaysian setting. Substantial challenges have been identified, particularly in relation to information systems for call and recall of women, as well as laboratory reporting and quality assurance. A cost-effective locally-specific approach to organized screening, that will provide the infrastructure for increasing participation in the cervical cancer screening program, is urgently required.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.5
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• pp.1-14
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• 2020

In order to improve the urban thermal environment, efforts are being made to increase green areas in cities that include park construction, planting, and green roofing. Among these efforts, urban parks play an important role not only in improving the urban thermal environment, but also in terms of ecosystem services (serving as resting places for citizens, providing cleaner air quality, reducing noise, etc.). Therefore, the purpose of this study is to suggest planning and management guidelines for urban parks that are effective in improving the thermal environment, by analyzing the urban surface temperature reduction performance of urban parks. To do this, first, land surface temperature was calculated by using Landsat 8 images. Second, the PCI (Park Cool Island) index was calculated to identify the temperature reduction performance of urban parks. Third, the characteristics of parks (area, shape, vegetation) and the surrounding spatial characteristics (land cover, building-related variables, etc.) were identified. Finally, the relationship between the PCI indices (PCI scale, PCI effect, PCI intensity) and the characteristics of the parks and their surroundings were analyzed. The results revealed that the parks consisting of a larger area, simple shape, and higher tree coverage ratio had increased PCI performance, and were advantageous for improving the urban thermal environment. Meanwhile, PCI performance was found to have decreased in areas with a higher impermeable area ratio and building coverage ratio. The outcomes of this study can be used to identify priority areas for planning and management of urban parks and can also be utilized as planning and management guidelines for improving urban thermal environment.

• Journal of Environmental Science International
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• v.13 no.12
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• pp.1023-1032
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• 2004

Rapid progress in urbanization has resulted in a change of the micro climate, especially in the urban area. In order to investigate the phenomenon of the heat island in the residential micro climate, a field survey was carried out by 4 sets of the residential type in Jeonju under typical winter synoptic condition. As analytic methode, it is used the comparison on the relation of the Land-to-Coverage Rate to Heat Island and Oxygen Concentration. And as a key question it is asked how stable characteristics of the micro climate will result from the survey of the Heat Island and the Oxygen Concentration, used as indicator. To ensure the trustworthy result of research, it is calculated the critical influence of the wind velocity and the Land-to-Covearage Rate. As a result of comparative analysis, it could be confirmed that the local temperatures in all sets of the residential type were higher than the average temperature in Jeonju. But the housing type A 'exclusive use for housing zone' has relativly the most stable and best living condition. On the contrary the residential type B and D has the worst toward the oxygen concentration in the time zone 9-12 a.m., which didn't reach the minimum of the oxygen concentration $20.5{\%}.$ It means that the higer the development and population density is, the worse is the situation of the Quality of Life in the residential types in accordance with the heat island and oxygon con­centration.

• Archives of Reconstructive Microsurgery
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• v.20 no.1
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• pp.1-7
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• 2011

The aim of extremity reconstruction has focused on early wound coverage and functional recovery but rarely aesthetics. As the quality of life improves, however, the request for aesthetics has been growing. The authors has conducted retrospective reviews on the 86 cases that had extremity reconstruction using free flap, considering the characteristics of parts that had been assessed in primary operation between May 1996 and December 2010. Aesthetic grading was performed in four categories; color, texture, contour and marginal scar. Recipient sites were 42 hands, 19 feet, 14 lower extremities excluding feet and 10 upper extremities apart from the hand. Types of free flap were 16 latissimus dorsi free flaps, 13 anterolateral thigh free flaps, 12 dorsalis pedis free flaps, 8 transvers rectus abdominis free flaps, 7 gracillis free flaps, and 5 superficial temporal fascia free flaps. Total flap necrosis was seen in 8 cases(9.3%) and partial necrosis in 5 cases(5.8%). Secondary revision was done in 24 cases(27.9%) and the most common revision, debulking was done in 14 cases(16.3%). The authors has considered cosmetic aspects along with wound coverage and functional recovery in primary reconstruction. The results of aesthetic grading was 16.2 out of 20, and the secondary revision rate was reduced.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.9A
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• pp.1031-1038
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• 2004

The call admission control algorithm of hybrid scheme is proposed to enhance the QoS(quality of service) of attempted multimedia calls. In the initial stage of 3rd generation multimedia services networks, the major limitations include the small sefyice coverage and the limited radio link capacity. Because the initial massive deployment of network elements such as base stations, base station controllers, and mobile switching centers is restricted to populated areas and the other areas should be covered with the fewer network elements, the radio channel resources are hmited and coverage network is supposed to be established. Therefore the QoS of multimedia services is expected to be severely degraded when tentative traffic hot spot occurs frequently. Thus, the blocking probability of attempted calls mcreases when relatively large number of users try to place multimedia calls in a hot spot area of the wireless networks. In this situation, the proposed hybrid scheme can mitigate the degradation of the QoS of multimedia services by using the available radio channels of the neighboring cells.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.325-333
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• 1995

Laparoscopic cholecystectomy was introduced into Korea in 1990 and has been rapidly replacing open cholecystectomy when the indications were met. In this study a medical utilization and technology was assessed on the selected hospitalized patients with cholelithiasis who underwent open or laparoscopic cholecystectomy from April 1, 1991 to March 31, 1994. The results are as follows. Despite the low reimbursement rate by the health insurance, the number of laparoscopic cases have been steadily increased. The post-operative days before health insurance coverage were significantly shortened from 8.4 days to 4.6 days. The preoperative days before health insurance coverage were significantly shorted from 8.4 days to 4.0 days. The total length-of-stays in the hospital were also significantly shortened from 15.2 days to 10.7 and 9.8 days in laparoscopic cholecystectomy. The laparoscopic cholecystectomy showed low expenses in all aspects expect the average hospital charges per day. For the hospital to have cost containment, it is more effective if length-of-stay is shorter because of high daily inpatient hospital charge. The laparoscopic cholecystectomy also showed shortened anesthesia time and operation time compared with open cholecystectomy that were statistically significant. The mean anesthesia and operation time for open cholecystectomy were 113.2 and 90.2 minutes but those of laparoscopic cholecystectomy were 105.7 and 68.6 minutes. According to this study the laparoscopic cholecystectomy has reduced the medical expenditure and we recommend this procedure over open cholecystectomy. The further discussion on the different morbidity rate between two types of procedure is essential in providing quality medical care, and to educate specialist.

• Korean journal of communication and information
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• v.81
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• pp.225-271
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• 2017

What is the basic nature of Korean public broadcasting system? This research explores this question through an analysis of KBS news coverage of the Korean housing market. This study spotlights the internal news production processes. In detail, this study investigates newsroom routines, such as news selection, news gatherings, and news production. As a result, this study reveals KBS can be classified as "Publicity Model" following reasons. First, KBS news selection process stresses higher viewer ratings for competitive market share and belittles public interests of serving the citizen. This caused KBS news to provide fragmented and truncated news information and to constrict high quality news of significant information for citizen. Second, KBS newsroom operates under the minimum staff resource to produce news programmes and has developed official source dependency as a routine for news gathering. Third, under the limits of report format, KBS news worked as a neutral deliverer of government message and failed to provide more detailed information and diverse viewpoints.