Search results for: Yoon Hwa Park
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 994

Search results for: Yoon Hwa Park

754 Soil-Vegetation Relationship in the Watersheds of the Tonga and OubeïRa Lakes, Algeria

Authors: Nafaa Zaafour

Abstract:

Located at the north eastern of Algeria, the National Park of El-Kala (PNEK) is a set of landscapes whose bioclimatic stages of vegetation extend from sub-humid to humid. In order to know the soil occupation in this complex, an initiated ecological soil cartography using a stratified sampling plan of vegetation had made, the study area occupies two-thirds of the northern National Park of El Kala, it has been divided into 380 plots of 1km2 of which, 76 were the subject of a detailed floristic inventory and sampling of soils. The inventory of vegetation carried out on different sites has allowed identifying several plant groups that share the soil cover with the following distribution: The group of cork oak, this formation occupies the biggest part of the area, it develops mainly on Incepttisols, Alfisols and Mollisols; The group of kermes oak, occupies a large area, it grows on Mollisols and Alfisols; The group of maritime pine, it occupies the same soils as the Kermes Oak; The group of Mirbeck oak, installed on Regosols, it is located in the Eastern part, on the Algerian-Tunisian border; The group of eucalyptus, it grows mainly on Inceptisols, Mollisols of, and Vertisols; The group of wetland, it grows along the banks of lakes and rivers, which primarily develops on Histosols soil Mollisols and Vertisols; The cultures, distributed mainly around the lakes occupy several soil types on Histosols, the Inceptisols, Mollisols of, and Vertisols. This great diversity of vegetation is linked not only to the soil variability but also to climate, hydrological and geological variability.

Keywords: Algeria, cartography, soil, vegetation

Procedia PDF Downloads 351
753 Frequency Offset Estimation Schemes Based on ML for OFDM Systems in Non-Gaussian Noise Environments

Authors: Keunhong Chae, Seokho Yoon

Abstract:

In this paper, frequency offset (FO) estimation schemes robust to the non-Gaussian noise environments are proposed for orthogonal frequency division multiplexing (OFDM) systems. First, a maximum-likelihood (ML) estimation scheme in non-Gaussian noise environments is proposed, and then, the complexity of the ML estimation scheme is reduced by employing a reduced set of candidate values. In numerical results, it is demonstrated that the proposed schemes provide a significant performance improvement over the conventional estimation scheme in non-Gaussian noise environments while maintaining the performance similar to the estimation performance in Gaussian noise environments.

Keywords: frequency offset estimation, maximum-likelihood, non-Gaussian noise environment, OFDM, training symbol

Procedia PDF Downloads 323
752 Event Related Potentials in Terms of Visual and Auditory Stimuli

Authors: Seokbeen Lim, KyeongSeok Sim, DaKyeong Shin, Gilwon Yoon

Abstract:

Event-related potential (ERP) is one of the useful tools for investigating cognitive reactions. In this study, the potential of ERP components detected after auditory and visual stimuli was examined. Subjects were asked to respond upon stimuli that were of three categories; Target, Non-Target and Standard stimuli. The ERP after stimulus was measured. In the experiment of visual evoked potentials (VEPs), the subjects were asked to gaze at a center point on the monitor screen where the stimuli were provided by the reversal pattern of the checkerboard. In consequence of the VEP experiments, we observed consistent reactions. Each peak voltage could be measured when the ensemble average was applied. Visual stimuli had smaller amplitude and a longer latency compared to that of auditory stimuli. The amplitude was the highest with Target and the smallest with Standard in both stimuli.

Keywords: auditory stimulus, EEG, event related potential, oddball task, visual stimulus

Procedia PDF Downloads 256
751 Sustainable Environmental Management through the Comparative Study of Two Recreational Parks in Nigeria

Authors: Oluwagbemiga Paul Agboola, Cornelius Olatunji Omojola, Dayo Martins Oyeshomo

Abstract:

The role of a recreational park in human and environmental development has attracted much interest in the recent time. Recreation parks' development could act as an effective planning strategy to enhance environmental sustainability, social cohesiveness, and users' quality of life. Similarly, parks enhance neighbourhood's aesthetics, refresh the air and enhance humans' contact with nature. In this connection, recreation parks create natural surroundings of rural areas for leisure, relaxation, recreation, psychological and physical comfort of the people. The purpose of this paper is to investigate the effectiveness of the two recreational parks' development as a strategy for neighbourhood's environmental improvement, sustainability and the recreationists' cohesiveness. A total number of 158 survey questionnaires were distributed to the tourists at Ikogosi cold and warm spring in Ekiti state as well as Olumirin waterfalls, Erin-Ijesa, Osun State, in South-West, Nigeria. The quantitative results of the analyzed data with Relative Importance Index (RII) revealed that recreation parks provide optimum opportunities for users' social cohesiveness and well-being while parks' sustainable environment could be enhanced base on the provision of essential facilities, services, and future developmental plans. It is recommended that for recreation parks to realize their full potential in environmental sustainability, adequate maintenance and provision of essential facilities becomes imperative.

Keywords: environmental sustainability, neighbourhood development, recreational park, Nigeria

Procedia PDF Downloads 196
750 Language Shapes Thought: An Experimental Study on English and Mandarin Native Speakers' Sequencing of Size

Authors: Hsi Wei

Abstract:

Does the language we speak affect the way we think? This question has been discussed for a long time from different aspects. In this article, the issue is examined with an experiment on how speakers of different languages tend to do different sequencing when it comes to the size of general objects. An essential difference between the usage of English and Mandarin is the way we sequence the size of places or objects. In English, when describing the location of something we may say, for example, ‘The pen is inside the trashcan next to the tree at the park.’ In Mandarin, however, we would say, ‘The pen is at the park next to the tree inside the trashcan.’ It’s clear that generally English use the sequence of small to big while Mandarin the opposite. Therefore, the experiment was conducted to test if the difference of the languages affects the speakers’ ability to do the different sequencing. There were two groups of subjects; one consisted of English native speakers, another of Mandarin native speakers. Within the experiment, three nouns were showed as a group to the subjects as their native languages. Before they saw the nouns, they would first get an instruction of ‘big to small’, ‘small to big’, or ‘repeat’. Therefore, the subjects had to sequence the following group of nouns as the instruction they get or simply repeat the nouns. After completing every sequencing and repetition in their minds, they pushed a button as reaction. The repetition design was to gather the mere reading time of the person. As the result of the experiment showed, English native speakers reacted more quickly to the sequencing of ‘small to big’; on the other hand, Mandarin native speakers reacted more quickly to the sequence ‘big to small’. To conclude, this study may be of importance as a support for linguistic relativism that the language we speak do shape the way we think.

Keywords: language, linguistic relativism, size, sequencing

Procedia PDF Downloads 251
749 EEG Signal Processing Methods to Differentiate Mental States

Authors: Sun H. Hwang, Young E. Lee, Yunhan Ga, Gilwon Yoon

Abstract:

EEG is a very complex signal with noises and other bio-potential interferences. EOG is the most distinct interfering signal when EEG signals are measured and analyzed. It is very important how to process raw EEG signals in order to obtain useful information. In this study, the EEG signal processing techniques such as EOG filtering and outlier removal were examined to minimize unwanted EOG signals and other noises. The two different mental states of resting and focusing were examined through EEG analysis. A focused state was induced by letting subjects to watch a red dot on the white screen. EEG data for 32 healthy subjects were measured. EEG data after 60-Hz notch filtering were processed by a commercially available EOG filtering and our presented algorithm based on the removal of outliers. The ratio of beta wave to theta wave was used as a parameter for determining the degree of focusing. The results show that our algorithm was more appropriate than the existing EOG filtering.

Keywords: EEG, focus, mental state, outlier, signal processing

Procedia PDF Downloads 257
748 An Automatic Speech Recognition Tool for the Filipino Language Using the HTK System

Authors: John Lorenzo Bautista, Yoon-Joong Kim

Abstract:

This paper presents the development of a Filipino speech recognition tool using the HTK System. The system was trained from a subset of the Filipino Speech Corpus developed by the DSP Laboratory of the University of the Philippines-Diliman. The speech corpus was both used in training and testing the system by estimating the parameters for phonetic HMM-based (Hidden-Markov Model) acoustic models. Experiments on different mixture-weights were incorporated in the study. The phoneme-level word-based recognition of a 5-state HMM resulted in an average accuracy rate of 80.13 for a single-Gaussian mixture model, 81.13 after implementing a phoneme-alignment, and 87.19 for the increased Gaussian-mixture weight model. The highest accuracy rate of 88.70% was obtained from a 5-state model with 6 Gaussian mixtures.

Keywords: Filipino language, Hidden Markov Model, HTK system, speech recognition

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747 Failure Analysis Using Rtds for a Power System Equipped with Thyristor-Controlled Series Capacitor in Korea

Authors: Chur Hee Lee, Jae in Lee, Minh Chau Diah, Jong Su Yoon, Seung Wan Kim

Abstract:

This paper deals with Real Time Digital Simulator (RTDS) analysis about effects of transmission lines failure in power system equipped with Thyristor Controlled Series Capacitance (TCSC) in Korea. The TCSC is firstly applied in Korea to compensate real power in case of 765 kV line faults. Therefore, It is important to analyze with TCSC replica using RTDS. In this test, all systems in Korea, other than those near TCSC, were abbreviated to Thevenin equivalent. The replica was tested in the case of a line failure near the TCSC, a generator failure, and a 765-kV line failure. The effects of conventional operated STATCOM, SVC and TCSC were also analyzed. The test results will be used for the actual TCSC operational impact analysis.

Keywords: failure analysis, power system, RTDS, TCSC

Procedia PDF Downloads 93
746 Diagonal Crack Width of RC Members with High Strength Materials

Authors: J. Y. Lee, H. S. Lim, S. H. Yoon

Abstract:

This paper presents an analysis of the diagonal crack widths of RC members with various types of materials by simulating a compatibility-aided truss model. The analytical results indicated that the diagonal crack width was influenced by not only the shear reinforcement ratio but also the yield strength of shear reinforcement and the compressive strength of concrete. The yield strength of shear reinforcement and the compressive strength of concrete decreased the diagonal shear crack width of RC members for the same shear force because of the change of shear failure modes. However, regarding the maximum shear crack width at shear failure, the shear crack width of the beam with high strength materials was greater than that of the beam with normal strength materials.

Keywords: diagonal crack width, high strength stirrups, high strength concrete, RC members, shear behavior

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745 Whether Buffer Zone Community Forests’ Benefits Are Distributed Fairly to Low-Income Users: Reflection From the Buffer Zone Community Forests in Bardia National Park, Nepal

Authors: Keshav Raj Acharya, Thakur Silwal, Neelam C. Poudyal

Abstract:

Buffer zones, the peripheral areas around the national parks and wildlife reserves, are available for the purpose of benefitting the local inhabitants by providing forest products for subsistence needs of basic forest products outside the protected areas. The forest area within the buffer zone has been managed as a buffer zone community forest (BZCF) for the last 25 years after the approval of the buffer zone management regulation 1996. With a case study of select BZCF in Bardia National Park, this study aims to analyze whether the benefit provided by BZCF is equally available to poor users among other socioeconomic classes of the users. The findings are based on the analysis of cross-sectional data involving household surveys (n=305) and key informants’ interviews (n=10) as well as office records available at different 5 buffer zone community forest user groups offices. Results indicate that despite the provisions of subsidized rates for poor; poor households were more deprived due to higher forest products price particularly, the timber price in buffer zone. Evidence also indicate that due to the increased forest coverage, the incidence of wildlife damage has also increased and impacted the poor more due to lack of land ownership as well as limited alternatives. Clear community forest management guidelines with equitable benefit sharing and compensatory mechanisms to the users of poor socioeconomic class have been identified as a solution to increase the benefit to poor users in BZCFUGs.

Keywords: crop depredation, forest products, users, wellbeing ranking

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744 Suitability Verification of Cellulose Nanowhisker as a Scaffold for Bone Tissue Engineering

Authors: Moon Hee Jung, Dae Seung Kim, Sang-Myung Jung, Gwang Heum Yoon, Hoo Cheol Lee, Hwa Sung Shin

Abstract:

Scaffolds are an important part to support growth and differentiation of osteoblast for regeneration of injured bone in bone tissue engineering. We utilized tunicate cellulose nanowhisker (CNW) as scaffold and developed complex system that can enhance differentiation of osteoblast by applying mechanical stimulation. CNW, a crystal form of cellulose, has high stiffness with a large surface area and is useful as a biomedical material due to its biodegradability and biocompatibility. In this study, CNW was obtained from tunicate extraction and was confirmed for its adhesion, differentiation, growth of osteoblast without cytotoxicity. In addition, osteoblast was successfully differentiated under mechanical stimulation, followed by calcium dependent signaling. In conclusion, we verified suitability of CNW as scaffold and possibility of bone substitutes.

Keywords: osteoblast, cellulose nanowhisker, CNW, mechanical stimulation, bone tissue engineering, bone substitute

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743 Promotion of Lipid Syntheses of Microalgae by Microfluidic-Assisted Membrane Distortion

Authors: Seul Ki Min, Gwang Heum Yoon, Jung Hyun Joo, Hwa Sung Shin

Abstract:

Cellular membrane distortion is known as a factor to change intracellular signaling. However, progress of relevant studies is difficult because there are no facilities that can control membrane distortion finely. In this study, we developed microfluidic device which can inflict mechanical stress on cell membrane of Chlamydomonas reinhardtii using regular height of the channels. And cellular physiological changes were analyzed from cells cultured in the device. Excessive calcium ion influx through into cytoplasm was induced from mechanical stress. The results revealed that compressed cells had up-regulated Mat3 mRNA which regulates cell size and cell cycle from a prolonged G1 phase. Additionally, TAG used for the production of biodiesel was raised rapidly from 4 h after compression. Taken together, membrane distortion can be considered as an attractive inducer for biofuel production.

Keywords: mechanical stress, membrane distortion, Chlamydomonas reinhardtii, deflagellation, cell cycle, lipid metabolism

Procedia PDF Downloads 342
742 Fixed-Bed Column Studies of Green Malachite Removal by Use of Alginate-Encapsulated Aluminium Pillared Clay

Authors: Lazhar mouloud, Chemat Zoubida, Ouhoumna Faiza

Abstract:

The main objective of this study, concerns the modeling of breakthrough curves obtained in the adsorption column of malachite green into alginate-encapsulated aluminium pillared clay in fixed bed according to various operating parameters such as the initial concentration, the feed rate and the height fixed bed, applying mathematical models namely: the model of Bohart and Adams, Wolborska, Bed Depth Service Time, Clark and Yoon-Nelson. These models allow us to express the different parameters controlling the performance of the dynamic adsorption system. The results have shown that all models were found suitable for describing the whole or a definite part of the dynamic behavior of the column with respect to the flow rate, the inlet dye concentration and the height of fixed bed.

Keywords: adsorption column, malachite green, pillared clays, alginate, modeling, mathematic models, encapsulation.

Procedia PDF Downloads 478
741 Identification of Spam Keywords Using Hierarchical Category in C2C E-Commerce

Authors: Shao Bo Cheng, Yong-Jin Han, Se Young Park, Seong-Bae Park

Abstract:

Consumer-to-Consumer (C2C) E-commerce has been growing at a very high speed in recent years. Since identical or nearly-same kinds of products compete one another by relying on keyword search in C2C E-commerce, some sellers describe their products with spam keywords that are popular but are not related to their products. Though such products get more chances to be retrieved and selected by consumers than those without spam keywords, the spam keywords mislead the consumers and waste their time. This problem has been reported in many commercial services like e-bay and taobao, but there have been little research to solve this problem. As a solution to this problem, this paper proposes a method to classify whether keywords of a product are spam or not. The proposed method assumes that a keyword for a given product is more reliable if the keyword is observed commonly in specifications of products which are the same or the same kind as the given product. This is because that a hierarchical category of a product in general determined precisely by a seller of the product and so is the specification of the product. Since higher layers of the hierarchical category represent more general kinds of products, a reliable degree is differently determined according to the layers. Hence, reliable degrees from different layers of a hierarchical category become features for keywords and they are used together with features only from specifications for classification of the keywords. Support Vector Machines are adopted as a basic classifier using the features, since it is powerful, and widely used in many classification tasks. In the experiments, the proposed method is evaluated with a golden standard dataset from Yi-han-wang, a Chinese C2C e-commerce, and is compared with a baseline method that does not consider the hierarchical category. The experimental results show that the proposed method outperforms the baseline in F1-measure, which proves that spam keywords are effectively identified by a hierarchical category in C2C e-commerce.

Keywords: spam keyword, e-commerce, keyword features, spam filtering

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740 Fatigue Evaluation of Link Slab for Continuous Girder-Type Precast Modular Bridges

Authors: Jae-Joon Song, Sang-Yoon Lee, Bong-Chul Joo

Abstract:

The girder-type precast modular bridge has been developed as a simply supported bridge. The girder-type precast modular bridge could be applied to the multi-span bridges through the continuity method. The continuity of the girder-type precast modular bridge is achieved by using the link slab which is easy to construction and appropriate to the rapid construction. In this study, the link slab with transition zone was used for the continuity of the precast modular bridges, and the construction detail of link slab was modified. In addition, the modified iterative design method of link slab was proposed in this study. To verify the proposed design method, the fatigue test using the mock-up specimen was conducted with cycle loading condition up to two million cycles.

Keywords: precast, modular bridge, link slab

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739 Microstructure and High Temperature Deformation Behavior of Cast 310S Alloy

Authors: Jung-Ho Moon, Myung-Gon Yoon, Tae Kwon Ha

Abstract:

High temperature deformation behavior of cast 310S stainless steel has been investigated in this study by performing tensile and compression tests at temperatures from 900 to 1200°C. Rectangular ingots of which the dimensions were 350×350×100 in millimeter were cast using vacuum induction melting. Phase equilibrium was calculated using the FactSage®, thermodynamic software and database. Thermal expansion coefficient was also measured on the ingot in the temperature range from room temperature to 1200°C. Tensile strength of cast 310S stainless steel was 9 MPa at 1200°C, which is a little higher than that of a wrought 310S. With temperature decreased, tensile strength increased rapidly and reached up to 72 MPa at 900°C. Elongation also increased with temperature decreased. Microstructure observation revealed that σ phase was precipitated along the grain boundary and within the matrix over 1200°C, which is detrimental to high temperature elongation.

Keywords: stainless steel, STS 310S, high temperature deformation, microstructure, mechanical properties

Procedia PDF Downloads 364
738 Parametric Study for Optimal Design of Hybrid Bridge Joint

Authors: Bongsik Park, Jae Hyun Park, Jae-Yeol Cho

Abstract:

Mixed structure, which is a kind of hybrid system, is incorporating steel beam and prestressed concrete beam. Hybrid bridge adopting mixed structure have some merits. Main span length can be made longer by using steel as main span material. In case of cable-stayed bridge having asymmetric span length, negative reaction at side span can be restrained without extra restraining devices by using weight difference between main span material and side span material. However angle of refraction might happen because of rigidity difference between materials and stress concentration also might happen because of abnormal loading transmission at joint in the hybrid bridge. Therefore the joint might be a weak point of the structural system and it needs to pay attention to design of the joint. However, design codes and standards about the joint in the hybrid-bridge have not been established so the joint designs in most of construction cases have been very conservative or followed previous design without extra verification. In this study parametric study using finite element analysis for optimal design of hybrid bridge joint is conducted. Before parametric study, finite element analysis was conducted based on previous experimental data and it is verified that analysis result approximated experimental data. Based on the finite element analysis results, parametric study was conducted. The parameters were selected as those have influences on joint behavior. Based on the parametric study results, optimal design of hybrid bridge joint has been determined.

Keywords: parametric study, optimal design, hybrid bridge, finite element analysis

Procedia PDF Downloads 390
737 Assessing the Spatial Distribution of Urban Parks Using Remote Sensing and Geographic Information Systems Techniques

Authors: Hira Jabbar, Tanzeel-Ur Rehman

Abstract:

Urban parks and open spaces play a significant role in improving physical and mental health of the citizens, strengthen the societies and make the cities more attractive places to live and work. As the world’s cities continue to grow, continuing to value green space in cities is vital but is also a challenge, particularly in developing countries where there is pressure for space, resources, and development. Offering equal opportunity of accessibility to parks is one of the important issues of park distribution. The distribution of parks should allow all inhabitants to have close proximity to their residence. Remote sensing and Geographic information systems (GIS) can provide decision makers with enormous opportunities to improve the planning and management of Park facilities. This study exhibits the capability of GIS and RS techniques to provide baseline knowledge about the distribution of parks, level of accessibility and to help in identification of potential areas for such facilities. For this purpose Landsat OLI imagery for year 2016 was acquired from USGS Earth Explorer. Preprocessing models were applied using Erdas Imagine 2014v for the atmospheric correction and NDVI model was developed and applied to quantify the land use/land cover classes including built up, barren land, water, and vegetation. The parks amongst total public green spaces were selected based on their signature in remote sensing image and distribution. Percentages of total green and parks green were calculated for each town of Lahore City and results were then synchronized with the recommended standards. ANGSt model was applied to calculate the accessibility from parks. Service area analysis was performed using Network Analyst tool. Serviceability of these parks has been evaluated by employing statistical indices like service area, service population and park area per capita. Findings of the study may contribute in helping the town planners for understanding the distribution of parks, demands for new parks and potential areas which are deprived of parks. The purpose of present study is to provide necessary information to planners, policy makers and scientific researchers in the process of decision making for the management and improvement of urban parks.

Keywords: accessible natural green space standards (ANGSt), geographic information systems (GIS), remote sensing (RS), United States geological survey (USGS)

Procedia PDF Downloads 307
736 Analysis of Mechanotransduction-Induced Microalgae under Direct Membrane Distortion

Authors: Myung Kwon Cho, Seul Ki Min, Gwang Heum Yoon, Jung Hyun Joo, Sang Jun Sim, Hwa Sung Shin

Abstract:

Mechanotransduction is a mechanism that external mechanical stimulation is converted to biochemical activity in the cell. When applying this mechanism to the unicellular green algae Chlamydomonas reinhardtii, the dramatic result that the accumulation of intracellular lipid was up to 60% of dry weight basis occurred. Furthermore, various variations in cellular physiology occurred, but there is a lack of the development of the system and related research for applying that technology to control the mechanical stress and facilitate molecular analyses. In this study, applying a mechanical stress to microalgae, the microfluidic device system that finely induced direct membrane distortion of microalgae. Cellular membrane distortion led to deflagellation, calcium influx and lipid accumulation in microalgae. In conclusion, cytological studies such as mechanotransduction can be actualized by using this system and membrane distortion is a promising inducer for biodiesel production.

Keywords: mechanotransduction, microalgae, membrane distortion, biodiesel

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735 Genomic Surveillance of Bacillus Anthracis in South Africa Revealed a Unique Genetic Cluster of B- Clade Strains

Authors: Kgaugelo Lekota, Ayesha Hassim, Henriette Van Heerden

Abstract:

Bacillus anthracis is the causative agent of anthrax that is composed of three genetic groups, namely A, B, and C. Clade-A is distributed world-wide, while sub-clades B has been identified in Kruger National Park (KNP), South Africa. KNP is one of the endemic anthrax regions in South Africa with distinctive genetic diversity. Genomic surveillance of KNP B. anthracis strains was employed on the historical culture collection isolates (n=67) dated from the 1990’s to 2015 using a whole genome sequencing approach. Whole genome single nucleotide polymorphism (SNPs) and pan-genomics analysis were used to define the B. anthracis genetic population structure. This study showed that KNP has heterologous B. anthracis strains grouping in the A-clade with more prominent ABr.005/006 (Ancient A) SNP lineage. The 2012 and 2015 anthrax isolates are dispersed amongst minor sub-clades that prevail in non-stabilized genetic evolution strains. This was augmented with non-parsimony informative SNPs of the B. anthracis strains across minor sub-clades of the Ancient A clade. Pan-genomics of B. anthracis showed a clear distinction between A and B-clade genomes with 11 374 predicted clusters of protein coding genes. Unique accessory genes of B-clade genomes that included biosynthetic cell wall genes and multidrug resistant of Fosfomycin. South Africa consists of diverse B. anthracis strains with unique defined SNPs. The sequenced B. anthracis strains in this study will serve as a means to further trace the dissemination of B. anthracis outbreaks globally and especially in South Africa.

Keywords: bacillus anthracis, whole genome single nucleotide polymorphisms, pangenomics, kruger national park

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734 A Performance Comparison between Conventional and Flexible Box Erecting Machines Using Dispatching Rules

Authors: Min Kyu Kim, Eun Young Lee, Dong Woo Son, Yoon Seok Chang

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In this paper, we introduce a flexible box erecting machine (BEM) that swiftly and automatically transforms cardboard into a three dimensional box. Recently, the parcel service and home-shopping industries have grown rapidly, and there is an increasing need for various box types to ship various products. However, workers cannot fold thousands of boxes manually in a day. As such, automatic BEMs are garnering greater attention. This study takes equipment operation into consideration as well as mechanical improvements in order to design a BEM that is able to outperform its conventional counterparts. We analyzed six dispatching rules – First In First Out (FIFO), Shortest Processing Time (SPT), Earliest Due Date (EDD), Setup Avoidance, EDD + SPT, and EDD + Setup Avoidance – to determine which one was most suitable for BEM operation. Consequently, SPT and Setup Avoidance were found to be the most critical rules, followed by EDD + Setup Avoidance, EDD + SPT, EDD, and FIFO. This hierarchy was valid for both our conventional BEM and our new flexible BEM from the viewpoint of processing time. We believe that this research can contribute to flexible BEM management, which has the potential to increase productivity and convenience.

Keywords: automation, box erecting machine, dispatching rule, setup time

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733 Effect of Modeling of Hydraulic Form Loss Coefficient to Break on Emergency Core Coolant Bypass

Authors: Young S. Bang, Dong H. Yoon, Seung H. Yoo

Abstract:

Emergency Core Coolant Bypass (ECC Bypass) has been regarded as an important phenomenon to peak cladding temperature of large-break loss-of-coolant-accidents (LBLOCA) in nuclear power plants (NPP). A modeling scheme to address the ECC Bypass phenomena and the calculation of LBLOCA using that scheme are discussed in the present paper. A hydraulic form loss coefficient (HFLC) from the reactor vessel downcomer to the broken cold leg is predicted by the computational fluid dynamics (CFD) code with a variation of the void fraction incoming from the downcomer. The maximum, mean, and minimum values of FLC are derived from the CFD results and are incorporated into the LBLOCA calculation using a system thermal-hydraulic code, MARS-KS. As a relevant parameter addressing the ECC Bypass phenomena, the FLC to the break and its range are proposed.

Keywords: CFD analysis, ECC bypass, hydraulic form loss coefficient, system thermal-hydraulic code

Procedia PDF Downloads 201
732 Eco-Parcel As a Semi-Qualitative Approach to Support Environmental Impacts Assessments in Nature-Based Tourism Destinations

Authors: Halima Kilungu, Pantaleo, K. T. Munishi

Abstract:

Climate and land-cover change affect nature-based tourism (NBT) due to its attractions' close connection to natural environments and climate. Thus, knowledge of how each attraction reacts to the changing environments and devising simple yet science based approaches to respond to these changes from a tourism perspective in space and time is timely. Nevertheless, no specific approaches exist to address the knowledge gap. The eco-parcel approach is devised to address the gap and operationalized in Serengeti and Kilimanjaro National Parks: the most climate-sensitive NBT destinations in Africa. The approach is partly descriptive and has three simple steps: (1) to identify and define tourist attractions (i.e. biotic and abiotic attractions). This creates an important database of the most poorly kept information on attractions' types in NBT destinations. (2) To create a spatial and temporal link of each attraction and describe its characteristic environments (e.g. vegetation, soil, water and rock outcrops). This is the most limited attractions' information yet important as a proxy of changes in attractions. (3) To assess the importance of individual attractions for tourism based on tourists' preferences. This information enables an accurate assessment of the value of individual attractions for tourism. The importance of the eco-parcel approach is that it describes how each attraction emerges from and is connected to specific environments, which define its attractiveness in space and time. This information allows accurate assessment of the likely losses or gains of individual attractions when climate or environment changes in specific destinations and equips tourism stakeholders with informed responses.

Keywords: climate change, environmental change, nature-based tourism, Serengeti National Park, Kilimanjaro National Park

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731 Improving Research Collaborations in Medical Device Development in Korea from an SMEs’ Perspective

Authors: Yoon Chung Kim

Abstract:

In this coming aging society, medical device industry is expected to become one of the major industries. Since developing medical devices usually requires technology convergence, research collaboration is important, especially for some small and medium enterprises (SMEs) that do not have enough R&D resources in each related field. Collaboration in medical device development has some unique properties. Since it requires convergence technology, collaboration with different fields, and different types of people are often required. Since it requires clinical test, the development process usually takes longer and collaboration with hospitals is also required. However, despite these importance and uniqueness, collaboration in medical device development has not yet been widely studied. Thus, our research focuses on investigating collaborations in medical device development. For our research, we conducted surveys and interviews, especially with SMEs’ perspective in Korea. The result and discussion will be presented with a major impact factors for collaboration result, as well as future strategies that will improve and strengthen collaboration process in medical devices.

Keywords: medical device, SME, research collaboration, development, clinical

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730 Inter-Filling of CaO and MgO Mixed Layer in Surface Behavior of Al-Mg Alloys Containing Al2Ca

Authors: Seong-Ho Ha, Young-Ok Yoon, Shae K. Kim

Abstract:

Oxide layer of normal Al-Mg alloy can be characterized by upper MgO and lower MgAl2O4 spinel. The formation of the MgO outmost layer occurs by the surface segregation of Mg in the initial oxidation. After then, the oxidation is proceeded with the formation of MgA12O4 spinel beneath the MgO. Growth of the oxide layer is accelerated by constant formation of MgA12O4 spinel. On the other hand, the oxidation resistance of Al-Mg alloys can be significantly improved simply by Mg+Al2Ca master alloy use as the Mg alloying element and such an improvement is attributed to the CaO/MgO mixed layer. Al-Mg alloy containing Al2Ca shows CaO as the upper layer and MgO as the lower one without MgA12O4 spinel. Such a dense oxide film acts as a protective layer. However, the CaO/MgO scale has the outmost MgO, partly, after a long time exposure to a harsh oxidation condition. The aim of this study is to investigate the inter-filling behaviour of CaO and MgO mixed layer in oxidation resistance mechanism of Al-Mg alloys containing Al2Ca. The process of outmost MgO layer formation will be clarified.

Keywords: Al-Mg alloy, Al2Ca, oxidation, MgO

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729 Characteristics of Butterfly Communities according to Habitat Types of Jeongmaek in Korea

Authors: Ji-Suk Kim, Dong-Pil Kim, Kee-Rae Gang, Yoon Ho Choi

Abstract:

This study was conducted to investigate the characteristics of butterfly communities according to the habitat characteristics of Korean veins. The survey sites were 12 mountains located in the vein, and 12~30 quadrats (200 in total) were set. The species richness and biodiversity were different according to land use type. Two types of land use (forest and graveyard) showed lower species diversity index values ​​than other land use types. The species abundance was low in the forest and graveyards, and grasslands, forest tops, cultivated areas and urban areas showed relatively high species richness. The altitude was not statistically significant with the number of species of butterflies and biodiversity index. The degree of canopy closure showed a negative correlation. As a result of interspecific correlation analysis, it was confirmed that there was a very high correlation (R2=0.746) between Lycaena phlaeas and Pseudozizeeria maha argia, Choaspes benjaminii japonica and Argyronome ruslana.

Keywords: land use type, species diversity index, correlation, canopy closure

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728 Effects of Topic Familiarity on Linguistic Aspects in EFL Learners’ Writing Performance

Authors: Jeong-Won Lee, Kyeong-Ok Yoon

Abstract:

The current study aimed to investigate the effects of topic familiarity and language proficiency on linguistic aspects (lexical complexity, syntactic complexity, accuracy, and fluency) in EFL learners’ argumentative essays. For the study 64 college students were asked to write an argumentative essay for the two different topics (Driving and Smoking) chosen by the consideration of topic familiarity. The students were divided into two language proficiency groups (high-level and intermediate) according to their English writing proficiency. The findings of the study are as follows: 1) the participants of this study exhibited lower levels of lexical and syntactic complexity as well as accuracy when performing writing tasks with unfamiliar topics; and 2) they demonstrated the use of a wider range of vocabulary, and longer and more complex structures, and produced accurate and lengthier texts compared to their intermediate peers. Discussion and pedagogical implications for instruction of writing classes in EFL contexts were addressed.

Keywords: topic familiarity, complexity, accuracy, fluency

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727 Optimization of Supercritical CO2 Power Cycle for Waste Heat Recovery from Gas Turbine with Respect to Cooling Condition

Authors: Young Min Kim, Jeong Lak Sohn, Eui Soo Yoon

Abstract:

This study describes the optimization of supercritical carbon dioxide (S-CO2) power cycle for recovering waste heat from a gas turbine. An S-CO2 cycle that recovers heat from small industrial and aeroderivative gas turbines can outperform a steam-bottoming cycle despite its simplicity and compactness. In using S-CO2 power cycles for waste heat recovery, a split cycle was studied to maximize the net output power by incorporating the utilization efficiency of the waste heat (lowering the temperature of the exhaust gas through the heater) along with the thermal efficiency of the cycle (minimizing the temperature difference for the heat transfer, exergy loss). The cooling condition of the S-CO2 WHR system has a great impact on the performance and the optimum low pressure of the system. Furthermore, the optimum high pressure of the S-CO2 WHR systems for the maximum power from the given heat sources is dependent on the temperature of the waste heat source.

Keywords: exergy loss, gas turbine, optimization, supercritical CO2 power cycle, split cycle, waste heat recovery

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726 Integrated Simulation and Optimization for Carbon Capture and Storage System

Authors: Taekyoon Park, Seokgoo Lee, Sungho Kim, Ung Lee, Jong Min Lee, Chonghun Han

Abstract:

CO2 capture and storage/sequestration (CCS) is a key technology for addressing the global warming issue. This paper proposes an integrated model for the whole chain of CCS, from a power plant to a reservoir. The integrated model is further utilized to determine optimal operating conditions and study responses to various changes in input variables.

Keywords: CCS, caron dioxide, carbon capture and storage, simulation, optimization

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725 Identifying the Conservation Gaps in Poorly Studied Protected Area in the Philippines: A Study Case of Sibuyan Island

Authors: Roven Tumaneng, Angelica Kristina Monzon, Ralph Sedricke Lapuz, Jose Don De Alban, Jennica Paula Masigan, Joanne Rae Pales, Laila Monera Pornel, Dennis Tablazon, Rizza Karen Veridiano, Jackie Lou Wenceslao, Edmund Leo Rico, Neil Aldrin Mallari

Abstract:

Most protected area management plans in the Philippines, particularly the smaller and more remote islands suffer from insufficient baseline data, which should provide the bases for formulating measureable conservation targets and appropriate management interventions for these protected areas. Attempts to synthesize available data particularly on cultural and socio-economic characteristic of local peoples within and outside protected areas also suffer from the lack of comprehensive and detailed inventories, which should be considered in designing adaptive management interventions to be used for those protected areas. Mt Guiting-guiting Natural Park (MGGNP) located in Sibuyan Island is one of the poorly studied protected areas in the Philippines. In this study, we determined the highly biologically important areas of the protected area using Maximum Entropy approach (MaxEnt) from environmental predictors (i.e., topographic, bioclimatic,land cover, and soil image layers) derived from global remotely sensed data and point occurrence data of species of birds and trees recorded during field surveys on the island. A total of 23 trigger species of birds and trees was modeled and stacked to generate species richness maps for biological high conservation value areas (HCVAs). Forest habitat change was delineated using dual-polarised L-band ALOS-PALSAR mosaic data at 25 meter spatial resolution, taken at two acquisition years 2007 and 2009 to provide information on forest cover ad habitat change in the island between year 2007 and 2009. Determining the livelihood guilds were also conducted using the data gathered from171 household interviews, from which demographic and livelihood variables were extracted (i.e., age, gender, number of household members, educational attainment, years of residency, distance from forest edge, main occupation, alternative sources of food and resources during scarcity months, and sources of these alternative resources).Using Principal Component Analysis (PCA) and Kruskal-Wallis test, the diversity and patterns of forest resource use by people in the island were determined with particular focus on the economic activities that directly and indirectly affect the population of key species as well as to identify levels of forest resource use by people in different areas of the park.Results showed that there are gaps in the area occupied by the natural park, as evidenced by the mismatch of the proposed HCVAs and the existing perimeters of the park. We found out that subsistence forest gathering was the possible main driver for forest degradation out of the eight livelihood guilds that were identified in the park. Determining the high conservation areas and identifyingthe anthropogenic factors that influence the species richness and abundance of key species in the different management zone of MGGNP would provide guidance for the design of a protected area management plan and future monitoring programs. However, through intensive communication and consultation with government stakeholders and local communities our results led to setting conservation targets in local development plans and serve as a basis for the reposition of the boundaries and reconfiguration of the management zones of MGGNP.

Keywords: conservation gaps, livelihood guilds, MaxEnt, protected area

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