• KIPS Transactions on Computer and Communication Systems
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• v.8 no.11
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• pp.263-270
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• 2019

Vehicular cloud computing is a new emerging technology that can provide drivers with cloud services to enable various vehicular applications. A vehicular cloud is defined as a set of vehicles that share their own resources. Vehicles should collaborate with each other to construct vehicular clouds through vehicle-to-vehicle communications. Since collaborating vehicles to construct the vehicular cloud have different speeds, directions and locations respectively, the vehicular cloud is constructed in multi-hop communication range. Due to intermittent wireless connectivity and low density of vehicles with the limited resources, the construction of vehicular cloud with multi-hop communications has become challenging in vehicular environments in terms of the service success ratio, the service delay, and the transmitted packet number. Thus, we propose a multi-hop vehicular cloud construction protocol that increases the service success ratio and decreases the service delay and the transmitted packet number. The proposed protocol uses a connection time-based intermediate vehicle selection scheme to reduce the cloud failure probability of multi-hop vehicular cloud. Simulation results conducted in various environments verify that the proposed protocol achieves better performance than the existing protocol.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.638-644
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• 2018

Relay systems have recently gained attentions because of its capability of cell coverage extension and the power gain as the one of key technologies for 5G. Relays can be exploited for small-cell base stations and the autonomous network, where communication devices communicate with each other cooperatively. Therefore, the relay technology is expected to enable the low power and large capacity communication. In order to maximize the benefits of using a limited number of relays, the efficient relay selection method is required. Especially, when two nodes exchange their data with each other via relay, the relay selection can maximize the average data rate by the spatial location of the relay. For this purpose, the average data rate is analyzed first according to the relay selection. In this paper, we analyzed the average data rate when two nodes exchange their data via dual-hop decode and forward relaying considering the interference by the concurrent transmission under Nakagami-m fading channel. The correctness of the analysis is verified by the Monte Carlo simulation. The results show that the concurrent transmission is superior to the non-concurrent transmission in the high required data rate region rather than in the low required data rate region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.38-46
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• 2019

This study analyzed the contents of KOSS-SF and PWI-SF by using ICF-VR core set and IPC framework for value judgment. The two instruments are self-report questionnaires commonly used for presenteeism in order to suggest vocational rehabilitation factors to predict presenteeism. The study was conducted from Dec 2018 to Feb 2019. For the analysis, the researchers independently linked the scales using the connection rules of ICF and IPC framework. The average agreement between the researchers was 90%. KOSS-SF was linked with 60 ICF-VR codes and PWI-SF with 34 ICF-VR codes, and mainly measured activities and participation, and body function domains. According to the IPC framework, the instruments were found to measure the Rational-Social, and Emotional-Psychological aspects. As a result, the two instruments did not adequately reflect the presenteeism (30% matched) and were particularly limited in ICF-VR environmental domains. Based on the results, questions of ICF body structure, environmental, and personal domains should be added to improve the validity of the presenteeism scale, and references and guidelines should be developed for collecting clearer data. Further study and discussion were provided.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.13-18
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• 2019

Sewage sludge treatment is increasing every year due to improvement of living and urbanization. However, interest in anaerobic digestion which is one of the recycling technology. There is anaerobic digestion of increasing due to limitations of ocean dumping and final disposal. But, the limit of anaerobic digestion efficiency due to the advanced treatment of sewage has been limited, and studies for solubilization technology have been actively conducted. Therefore, in this study, we aimed to investigate the variation of generation of scum and the solubilization efficiency in the application of pre-treatment of ozone reaction and the change of properties of digested sludge with wet milling. There are results of VS/TS increased by 4.4% and $SCOD_{cr}/TCOD_{cr}$ increased by 9.4% by wet milling alone. In addition, the increase of the specific surface area due to which the reduction of the particle size of the solid content of the sludge in the ozone reaction caused by wet milling decreased the generation rate of scum at 14.3% and increased VS/TS at 2.1%, compared with the ozone reaction alone. From these results, it is expected that the application of wet milling can be increased the contact efficiency with solids in the sludge during ozone reaction with suppress scum and increase the efficiency of the subsequent process in anaerobic digestion.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.32-32
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• 2019

Mutation breeding is the useful tool to improve agronomic traits in various crop species. Soybean is most important crop and is rich in protein and oil contents. Despite of the importance as economic value and various genetic resource of soybean, there have been limited studies of genetic relationship among mutant resources through radiation breeding. In this study, the agronomical phenotype for selecting various genetic resources was evaluated in 528 soybean mutant lines. As a result, 210 soybean mutants with their original cultivars were selected with various traits. We named 210 selected lines as Mutant Diversity Pool (MDP). The genetic diversity and the relationship of the MDP were investigated using TRAP and TE-TRAP markers. In TRAP analysis, sixteen primer combination (PC)s were used and a total of 551 fragments were amplified. The highest (84.00%) and the lowest (32.35%) polymorphism levels were showed in PC MIR157B+Ga5 and B14G14B+Ga3, respectively. The mean of PIC values was 0.15 ranging from 0.07 in B14G14B+Sa12 to 0.23 in MIR157B+Sa4. Phylogenetic and population structure analysis indicated that the 210 MDP lines dispersed to four groups among the wild types and their mutants. The highest genetic diversity among populations was observed between lines Paldal and 523-7 (Fst=0.409), whereas the lowest genetic diversity was between population KAS360-22 and 94seori (Fst=0.065). AMOVA showed 11.583 (21.0%) and 43.532 (79.0%) variations in inter and intra mutant population, respectively. Overall, the genetic similarity of each intra mutant populations was closer than that of inter mutant population. A total of 408 fragments were amplified in the 210 MDP using twelve PCs of TE-TRAP markers that were obtained from a combination of three TIR sequence of transposable elements (MITE-stowaway; M-s, MITE-tourist; M-t, PONG). The highest (77.42%) and the lowest (56.00%) polymorphism levels were showed in PONG+Sa4 and PONG+Sa12, respectively. The mean of PIC values was 0.15 ranging from 0.09 in M-s+Sa4 and M-s+Ga5 to 0.21 in M-t+Ga5. AMOVA of M-s showed 2.209 (20%) and 8.957 (80%) variations in inter and intra mutant population, respectively. AMOVA of M-t showed 2.766 (18%) and 12.385 (82%) variations in inter and intra mutant population, respectively. AMOVA of PONG showed 3.151 (29%) and 7.646 (71%) variations in inter and intra mutant population, respectively. According to our study, the PONG had higher inter mutant population and lower intra mutant population. This mean was that for aspect of radiation sensitivity, M-s and M-t showed higher mobility than that of PONG. Our results suggest that the TRAP and the TE-TRAP markers may be useful for assessing the genetic diversity and relationship among soybean MDP and help to improve our knowledge of soybean mutation/radiation breeding.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.4
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• pp.366-375
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• 2018

Evapotranspiration (ET) information is needed for many applications in agricultural and environmental resource management because crop yields, plant growth and physiological characteristics are primarily water limited. This study was conducted to evaluate the diurnal change of ET using electronic weighing lysimeter and to determine whether the ET of Cnidium officinale Makino could be manipulated through meteorological factors such as solar radiation, windy conditions and air temperature etc., Pot has a diameter of 35 cm and an height of 38 cm. A disturbed soil of sandy loam (coarse, mixed, mesic family of Dystric Fluventic Eutroudepts) within lysimeter has a mass of approximately 40.0 kg. In 2017, 10-minute recordings of data were used for measuring actual ET, and also evaluating a relationship between ET and meteorological factors during from 2 Aug. to 6 Aug. The maximum daily ET of Cnidium officinale was $44.04{\pm}3.949g$ per hour in lysimetric measurements. Diurnal changes of ET was highly correlated with solar radiation ($r^2=0.7778$) and followed by wind speed ($r^2=0.6400$). But on the other hand, air temperature was not consistent with ET ($r^2=0.2260$). This results imply that ET of Cnidium officinaele seems to be mainly governed by radiation energy in clear days, and approximately 40% of solar radiation is likely to be converted into ET. Therefore, weighing lysimeter can be used to accurately estimate actual ET and is expected to attract a great deal of attention to reliable application of water management in agriculture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.303-312
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• 2018

The university facility is made up of multiple buildings and has many maintenance items. In addition, administrative constraints need to be handled within a limited period. Most maintenance work is small scale and multi-work construction, such as waterproofing, needs to be organized. The facility manager makes annual unit price contract with a maintenance company and carries out the maintenance work. On the other hand, delay and rework is occurring because existing maintenance work performed without scheduling based on the manpower input. This study proposed a scheduling model that can support the facility manager to manage maintenance works of multiple university facilities at the program level. The model consists of three stages in order. In object analysis, details of the maintenance items were analyzed and the quantity is calculated based on the quantity takeoff sheet. In resource analysis, the craftsmen and construction period of detailed works are derived for the effective input of craftsmen. In scheduling, the priority of each work and the optimal manpower input are derived. The optimal schedule is selected according to the goodness of fit. The applicability and effectiveness of the prototype was evaluated through a case study and interviews with case participants. The model was found to be an effective tool to support the scheduling of maintenance works for the facility manager.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.454-460
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• 2020

The goal of this study was to classify the area of Larix kaempferi forest available for timber production, considering the legal, physical, environmental, and technical constraints, and to optimize the forest resources and the potential of timber production in South Korea for 50 years. The results showed that the area of Larix kaempferi forest available for timber production is limited to 124,000 ha, 48% of the total area. Without further efforts in resource management, sustainable timber production of Larix kaempferi cannot be guaranteed even at the current level of timber supply. To enhance the potential of timber production for this species, two alternatives were considered: a 705-km annual increment of forest roads (alternative 1) and a 1,000-kmannual increment of forest roads (alternative 2) to enlarge forest areas available for timber production. The results showed that alternative 1 is feasiblefor sustainable timber production both at the current level and with a 5% increment of timber supply. However, alternative 1 is not sufficient in the case of a 10% increment of timber supply with a low growing stock, whereas alternative 2 is sufficient. Therefore, an increase in forests roads as well as regeneration efforts are required to improve the timber production potential of Larix kaempferi in South Korea.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.2
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• pp.125-137
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• 2007

This paper proposes a new scheme to provide the location privacy of sources in Wireless Sensor Networks (WSNs). Because the geographical location of a source sensor reveals contextual information on an 'event' in WSN, anonymizing the source location is an important issue. Despite abundant research efforts, however, about data confidentiality and authentication in WSN, privacy issues have not been researched well so far. Moreover, many schemes providing the anonymity of communication parties in Internet and Ad-hoc networks are not appropriate for WSN environments where sensors are very resource limited and messages are forwarded in a hop-by-hop manner through wireless channel. In this paper, we first categorize the type of eavesdroppers for WSN as Global Eavesdropper and Compromising Eavesdropper. Then we propose a novel scheme which provides the anonymity of a source according to the types of eavesdroppers. Furthermore, we analyze the degree of anonymity of WSN using the entropy-based modeling method. As a result, we show that the proposed scheme improves the degree of anonymity compared to a method without any provision of anonymity and also show that the transmission range plays a key role to hide the location of source sensors.

• Journal of Environmental Impact Assessment
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• v.29 no.6
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• pp.430-440
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• 2020

The application contents, process, and its limitations are discussed for the setting of Korean legal guides & criteria for water cycle and ecological condition in development project of land use by thorough comparison and examination of prerequisites and credits of water cycle and soil+vegetation by USA's SITES (Sustainable Sites Initiative). In the case of SITES, due to the implementation procedure operated as a non-governmental independent assessment system by Green Business Certification, Inc, the natural condition of water cycle and soil-vegetation items-the key element of ecosystem services can be quantitatively assessed, well along with its legal and institutional guidelines and regulations. On the other hand, in the case of Korea, as a part of the national certification procedure for green building, the ecological area ratio system still have very limited role as an only amenity resource in the creation of artificial green spaces and insufficiency of management system for rain water. In conclusion, it was understood as an urgent situation in necessary for prompt establishment of site's sustainability certification system at the national level, based on management of water circulation and natural soil & vegetation in developed area with consideration of various land uses and types of development projects.