The aim of this study is to obtain basic data to set the direction for construct and managing auto campsites. A survey was conducted with users of an auto campsite located in Jangsu Nuri Park in October 2018, and 32 copies of the questionnaire were used in the analysis. Auto camping is typically undertaken for a night or two with family or friends/colleagues. The adequacy of fees and location are important factors in choosing the campsite, so it is desirable to build one in the suburbs of the city and offer it at a reasonable price. Proximity to tourist spots and convenience in using facilities are also factors that must be considered. People are generally engaged in activities such as taking walks, relaxing, and looking around campsites, and they want to enjoy various other amenities like attractions, experiences, entertainment, and active leisure options, which is why there must be facilities to support these behaviors. The first-time visitors of the campsite showed high satisfaction with its individual facilities, while repeat visitors showed high overall satisfaction, which indicates that satisfaction with individual elements did not lead to overall satisfaction.

LDV(laser Doppler velocimetry) measurements were conducted on the exit region of the impeller passage and the gap between the impeller and turbine blades under 0.8 speed ratio. The 0.8 speed ratio has an impeller speed of 2000rpm and a turbine speed of 1600rpm. A periodic variation of the mass flow rate is present in many of the measurements made. The frequency of this variation is the same as the frequency of the turbine blades passing the impeller passage exit. It is found that the instantaneous position of the turbine had effect on fluid flow inside the impeller passage and gap region. This study would aid in the construction of higher accuracy CFD models of this complex turbomachinery device.

In this study, a numerical approach based on mid-point integrated finite elements and a viscous boundary is proposed for time-domain wave-propagation analyses in infinite poroelastic media. The proposed approach is accurate, efficient, and easy to implement in time-domain analyses. In the approach, an infinite domain is truncated at some distance. The truncated domain is represented by mid-point integrated finite elements with real element-lengths and a viscous boundary is attached to the end of the domain. Given that the dynamic behaviors of the proposed model can be expressed in terms of mass, damping, and stiffness matrices only, it can be implemented easily in the displacement-based finite-element formulation. No convolutional operations are required for time-domain calculations because the coefficient matrices are constant. The proposed numerical approach is applied to typical wave-propagation and soil-structure interaction problems. The model is verified to produce accurate and stable results. It is demonstrated that the numerical approach can be applied successfully to nonlinear soil-structure interaction problems.

최근 밭농업의 기계화와 생력화에 대한 연구와 개발이 활성화되고 있다. 그러나 밭농업의 기계화율은 비교적 낮을 뿐 아니라, 농작업이 단계별로 기계화되고 있기 때문에 밭농업의 생력화에 기여하지 못하고 있다. 따라서 본 연구의 목적은 밭농업을 생력화하기 위하여 구현한 일관작업 복합기의 포장능률 및 비용분석을 통하여 생력화율을 평가하는데 있다. 경운·정지, 두둑성형, 방제, 멀칭 및 파종·정식모듈을 포함하여 다섯 작업모듈을 일관화한 복합기의 이론작업시간은 0.56hr/10a으로 관행과 비교하여 67%의 생력화율을 보였다. 유효포장능률은 0.09ha/hr로서 관행에 비하여 2.95배 우수하였고 부담면적은 9.07ha로 평가되었다. 비용분석에서는 복합기의 초기구입비가 43% 절감되는 것으로 평가되었으며 시간당 비용과 단위면적당(10a) 비용은 관행에 비하여 각각 68% 및 58% 정도 절감되었다. 따라서 트랙터 복합작업기를 이용한 일관화된 밭작업은 관행에 비하여 생력화에 상당히 기여하는 것으로 평가된다.

Incursions of red imported fire ant (RIFA), Solenopsis invicta into Korea have been increasing. After a first interception of a colony of S. invicta on Gamman pier, Pusan port while intensive surveillance by Animal & Plant Quarantine Agency (APQA) in September 2017, three more RIFA colonies have been found in sea port piers of Pyeongtek, Incheon and Pusan cities. The social forms and mitochondrial DNA haplotypes of the intercepted RIFA colonies were analysed by allelic discrimination assay (peptide nucleic acid probe based RT-PCR) of Gp-9 gene and mt-DNA fragment of 768 bp, which is part of the Cytochrome oxidaseⅠ gene. The colony on Gamman pier, intercepted in Sep. 2017 was previously reported as a haplotype 5 (H5) of mitochondrial DNA and a social form of polygyne. The colony on Hutchison pier of Pusan port, intercepted in June 2018 were confirmed as a H22 haplotype and a monogyne. Those different social forms show different origins of each colonies. Those on piers of Pyeongtek and Incheon ports, also found in 2018 were confirmed samely as H22 and monogyne. However, it could be putatively assumed that those two colonies were differently introduced via different container cargoes, considering those colonies were found in container yards of distantly located different sea ports. More genetic variation analyses using diverse sets of molecular markers such as microsatellites, genome-wide single nucleotide polymorphisms, etc. in nuclear gens are being proceeded for more exact introduction routes (origins).

The ability to recover the nearly limitless supply of uranium contained within the world’s oceans would provide supply security to uranium based fuel cycles. Therefore, in addition to U.S. national laboratories conducting R&D on a system capable of harvesting seawater uranium, a number of collaborative university partners have developed alternative technologies to complement the national laboratory scheme. This works summarizes the systems analysis of such novel uranium recovery technologies along with their potential impacts on seawater uranium recovery. While implementation of some recent developments can reduce the cost of seawater uranium by up to 30%, other researchers have sought to address a weakness while maintaining cost competitiveness.

In this paper, we study the existing results of the structure-soil-structure interaction (SSSI) effect on seismic responses of structures and summarize important parameters. The parameters considered in this study are a combination of buildings in the power block of a nuclear power plant, the characteristics of earthquake ground motions and its direction, and the characteristics embedded under the ground. Based on these parameters, the seismic analysis model of the structures in the power block of the nuclear power plant is developed and the structure-soil-structure interaction analyses are performed to analyze the influence of the parameters on the seismic response. For all analyses, the soil-structure interaction (SSI) analysis program CNU-KIESSI, which was developed to enable large-sized seismic analysis, is used. In addition, the SSI analyses is performed on individual structures and the results are compared with the SSSI analysis results. Finally, the influence of the parameters on the seismic response of the structure due to the SSSI effect is reviewed through comparison of the analysis results.

PURPOSES : This study was conducted to develop expressway safety treatments based on the analysis results of older driver behaviors through literature review, surveys, and driving simulator experiments. METHODS: In this study, three analyses were conducted: surveys of 700 older drivers to find the risk segments they recognized, driving simulator experiments with older and younger drivers to investigate driver behaviors, and expert surveys to find the priority of expressway safety treatments for older drivers. RESULTS : Through survey results it was found that merging areas and tunnels were identified as the most dangerous areas, and more dangerous older driver behaviors were observed on those expressway segments in the driving simulator experiments. In addition, the priorities of safety treatments for each segment of expressways were decided based on expert surveys. CONCLUSIONS: It was concluded that choice and concentration strategies of expressway safety treatments for older drivers should be applied as perceptions regarding dangerous spots and older driver behaviors, including geometric designs, safety facilities, regulation, and institutes to improve expressway safety.

Fluid motion within the internal combustion engine cylinder plays a major role in controlling the fuel/air mixing and combustion processes in spark-ignition engines, and the combustion processes in compressionignition engines. In-cylinder flow is quite unstable and varies from one cycle to another. Various methods of in-cylinder flow measurement and fuel/air mixing characterization have been developed during the past few decades. In particular, laser based flow diagnostic techniques have been utilized for this purpose. This study will focus on the quantification of spark-ignition engine in-cylinder flow using the laser based flow diagnostic techniques. The measurement methods, including high speed flow visualization and laser Doppler velocimetry (LDV), will be discussed.

Since more and more consumers rely on online consumer reviews in their purchase decision making, we have observed the emergence of empirical studies on online reviews in different contexts. Such studies look at various dimensions surrounding online reviews; nevertheless, none of them actually gives a more comprehensive picture as to the rating differences across online rating platforms and/or across time, let alone explains such differences. This study aims to address these understudied but managerially relevant issues. In our empirical study, we focus on hotel ratings across platforms and across time (i.e., across identified change point in time), and explain such differences by review text associating with the ratings. We investigated San Francisco hotels that were rated on both Tripadvisor and Expedia, and utilized the General Inquirer dictionary to identify the categories of words in a review. Regressions analyses were then conducted for the explanation of rating differences. We found that rating differences, in both the cross-platform and the longitudinal cases, are substantially associated with the number of words (in a negative relationship). Furthermore, word tags identified from the review text associated with ratings also explain the rating differences. To conclude, the research reveals that for a specific service provider, online ratings may vary significantly in both the cross-platform and the longitudinal senses. It demonstrates that adopting a systematic approach and utilizing an established semantic dictionary, information extracted from review text can substantially explain such differences.

This study investigated the volatile flavor composition of essential oils from Chrysanthemum zawadskii var. latilobum Kitamura and Aster yomena Makino. The essential oils obtained by the hydrodistillation extraction method from the aerial parts of the plants were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). One hundred (95.04%) volatile flavor compounds were identified in the essential oil from the C. zawadskii var. latilobum Kitamura. The major compounds were valencene (10.82%), δ-cadinol (9.77%), hexadecanoic acid (8.70%), 2-methyl-4-(2,6,6-trimethylcyclohex-1-enyl) but-2-en-1-ol (3.67%), and 2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4,4]non-3-ene (3.57%). Ninety-eight (93.83%) volatile flavor compounds were identified in the essential oil from the Aster yomena Makino. The major compounds were and 3-eicosyne (13.61%), 9,10,12-octadecatrienoic acid (7.8%), α-caryophyllene alcohol (6.83%), 9-octadecynoic acid (6.03%), and α-caryophyllene (5.74%). Although the two plants are apparently very similar, the chemical composition of the essential oils was significantly different in quality and quantity. In the case of C. zawadskii var. latilobum Kitamura, the sesquiterpene, valencene was found to be 10.82%, but it was not identified in A. yomena Makino. δ-Cadinol appeared higher in C. zawadskii var. latilobum Kitamura than in A. yomena Makino. A clear characteristic of A. yomena Makino essential oil is that it has a high content of caryophyllene derivatives. The α-caryophyllene alcohol contained in A. yomena Makino was relatively high at 6.83%, although the compound was not identified in C. zawadskii var. latilobum Kitamura. Also α-caryophyllene was shown to be higher in A. yomena Makino than in C. zawadskii var. latilobum Kitamura.

If asphalt-aggregate mixture is produced at a high temperature, the mixture will suffer a significant higher shortterm aging (STA) due to the elevated temperature. The binder in that mixture will be oxidized (aged) more than expected during STA due to the highly elevated temperature. The STA at the high-temperature level is one of the reasons why the hot-mix asphalt (HMA) mixture shows many distresses in the early stage of service life. In this respect, adopting warm-mix asphalt (WMA) technology is another advantage in the asphalt pavement industry. In this study, various levels of STA were used to evaluate aging levels of the binder in the mixture before and after STA. A gel-permeation chromatography (GPC) test was performed on the mixture particles without binder recovery to estimate the significance of aging for each case of STA. Statistical analyses were carried out to determine the difference in aging levels among STA temperatures. Statistical test results found that the aging level of the binder after STA was significantly higher than that of binders before STA at an α = 0.05 level. It was also found that the aging level of binders in the WMA mixture was significantly lower than that of binders in HMA after STA at an α = 0.05 level. It was observed that if an HMA mixture was produced at high-temperature STA, its aging level was estimated to be approximately four years in service.

This study investigated the chemical composition of burdock (Arctium lappa L.) leaves essential oil, and the quantitative changes of the major terpene compounds according to the specific harvesting season. The essential oils obtained by the hydrodistillation extraction (HDE) method from the aerial parts of the burdock leaves were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). The essential oil composition of this plant was characterized by the higher content of phytol and 6,10,14-trimethyl-2-pentadecanone. Seventy seven (98.28%) volatile flavor compounds were identified in the essential oil from the burdock leaves harvested during the spring season of 2012, and phytol (33.47%) and 6,10,14-trimethyl-2-pentadecanone (32.47%) were the most abundant compounds. Eighty eight (99.08%) compounds were identified in the essential oil from the leaves harvested during the autumn season of 2012, and in this case, phytol (37.35%) and 6,10,14-trimethyl-2-pentadecanone (34.67%) were also the most abundant compounds. These two volatile components were confirmed as the major oil components of the burdock leaves during the time of any harvest. The ratio between the two components contained in the burdock essential oils did not differ significantly by harvesting season. But overall, the essential oil harvested during the spring season contained 65.94% of the two major components, while for the essential oil harvested during the autumn season, the total amount of these two major components was 72.02%. While the main ingredients of the essential oils were found to be unchanged from one harvest time to the next, it was found to differ in content. For the burdock leaves, the quality index of the volatile constituents according to the harvest time would be more useful for utilizing the total quantity other than the proportion between phytol and 6,10,4-trimethyl-2-pentadecone.

A parametric study was carried out to gain an insight about structural performances considering abnormal behavior effects in high strength steel pipe strut system. Six load cases were considered as undesirable deflections of strut structures, which are basic load combination, excessive excavation situations, impact loading effects, additional overburden loads, load combinations, and 50% reduction of strut length. Subsequent simulation results present various influences of parameters on structural performances of the strut system. Based on the results, we propose methods to prevent unusual behaviors of pipe-type strut structures made of high strength steels.

Cluster of differentiation (CD) 24 or heat stable antigen 24 (HSA) molecule is a mucin-type glycoprotein attached to the cell surface by glycosylphosphatidylinositol (GPI)-anchor, promoting adhesive interactions between cells or in extracellular matrix. The aim of this study was to determine the not yet fully identified porcine CD24 gene and protein structure using computational analysis and to validate variants reported in exons of CD24 gene using direct sequencing. A total of 59 samples belonging to Yorkshire, Landrace, Berkshire, Jeju black pig and wild boar were used in the study. Human CD24 mRNA sequences were used as a reference and subjected to BLAST searches to retrieve the orthologous expressed sequence tags (ESTs) or cDNA sequences against NCBI and Ensemble databases. Assembled ESTs and retrieved cDNA sequences for the porcine CD24 gene were used for specific BLAST search to determine its genomic structure. We found porcine CD24 gene to consist of two exons and a relatively long intron. Second exon of porcine CD24 gene had a long 3’ untranslated region (UTR) and was very similar to that of human, mouse, rat, and sheep. The sequence homology of porcine CD24 protein was 65.38-84.62%, when analyzed with amino acid sequences of rat, mouse, human, cattle, and sheep CD24 protein. N-terminal signal sequence, O-glycosylation sites and GPI-anchoring signal sites were also predicted in pig, which showed these motifs to be evolutionary conserved across the species. Variant analysis in exonic regions of porcine CD24 among the multiple breeds showed that only second exon contained eight SNPs and three insertions in a 3’ UTR. Taken together, this study reports putative porcine CD24 gene and its protein structure using in silico approaches, which will be helpful for any further functional studies.

고준위 방사성폐기물로 분류되는 사용후핵연료를 현재 기술로 가장 안전한 격리 방법으로는 500 m 심도의 안정한 암반에 심지층 처분하는 방법으로, 가장 중요한 요건은 공학적방벽인 완충재의 온도가 100℃를 초과하지 않도록 시스템을 설계하 는 것이다. 국내의 경우 전체 전력 소요량의 약 30% 정도를 차지하고 있는 원자력발전으로 발생되는 사용후핵연료의 양은 지속적으로 증가하여 누적되고 있어, 이들을 처분하기 위한 소요면적도 증가하고 있다. 따라서, 본 연구에서는 처분면적을 감소시킴으로써 처분효율을 향상시키기 위한 목적으로 다양한 복층처분 개념을 도출하였다. 이를 바탕으로 중요한 처분시 스템 요건 만족여부를 확인하기 위하여 열해석을 수행하고 그 결과를 분석하여 처분시스템 열적 안정성을 평가하였다. 평 가결과, 기준시스템 위치인 500 m 심도로부터 상부 또는 하부로 75 m를 이격한 심도에 복층으로 처분시스템 구축이 가능 하였으며, 실제 부지특성자료에 따른 상세 분석이 요구된다. 본 연구결과는 사용후핵연료 관리정책 수립 및 실제 처분시스 템 설계에 활용될 것으로 사료된다.