• Title/Summary/Keyword: degree distribution

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Infection Properties of Oak Wilt Disease in Bukhansan National Park Adjacent to Metropolitan Areas in Korea

  • Choi, Jin-Woo;Yeum, Jung-Hun
    • Journal of Environmental Science International
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    • v.26 no.7
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    • pp.803-815
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    • 2017
  • In this study of the oak wilt disease that has occurred in a large scale in a protected area located near South Korea's metropolitan region, a detailed analysis has been conducted on the terrain, species and Diameters at Breast Height (DBH) of infected trees to identify the distribution of infection properties in the affected area. Taking into consideration the distribution of oak tree vegetation, a total of 4,640 quadrats in a size of 10 m by 10 m, have been set; and oak tree species, the DBH and infection damage per quadrat have been investigated. Geological properties have been analyzed according to elevation, slope, aspect and micro topography while a weighted value has been given according to the degree of infection in order to calculate an infection index. Through correlation analysis, the infection ratio of seriously-damaged and withered trees and the infection index have been analyzed with regards to the geological properties, tree species and DBH. The analysis shows that the disease tends to affect an area with medium elevation rather than those in the highest or lowest areas and that serious damage has been observed at rugged spots with a steep gradient (more than $30^{\circ}$). Although there has been no distinct tendency with regards to aspect, the infection ratio is relatively high in areas facing the north while the seriously-damaged and withered ratio are high in areas facing the south. In terms of micro topography, more damage has been spotted in valley terrain. Quercus mongolica has sustained more damage than other species. When it comes to the DBH, as seen in previous studies, large trees have suffered severe damage, but the analysis has also revealed conspicuous damage to medium trees with a DBH of 15-20 cm, which had not previously been considered at high risk.

Case Study of Workload Distribution Index for RTGC in Container Terminal Yard (컨테이너 터미널의 RTGC작업 분산지표 적용연구 - H사를 중심으로 -)

  • Shin, Chang-Hoon;Park, Jong-Won;Kwon, Min-Kyun;Shin, Jae-Young
    • Journal of Navigation and Port Research
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    • v.41 no.4
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    • pp.229-234
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    • 2017
  • Container terminal yards operate under a high degree of uncertainty as the contact point between inbound and outbound operations of vessels and external trucks. The layout, equipment operations. and job orders at the yards determine the efficacy and delays of the work, so many studies have investigated improvements in efficiency. H company, a container terminal operator developed an index called WDI to distribute work among RTGCs. The WDI is an indicator to prevent congestion in one place by equally distributing the work to each RTGC. This paper analyzes the effect of the WDI introduction and discusses the causes and results of the WDI introduction effect from quantitative and qualitative perspectives.

Distribution of Actual Vegetation and Management of Bukhansan National Park (북한산국립공원의 현존식생분포 및 관리)

  • Oh, Koo-Kyoon;Kim, Do-Gyun;Kim, Chul-Eui
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.83-97
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    • 2008
  • This study was carried out to investigate the actual vegetation and Degree of Green Naturality(DGN) and distribution of exotic plants replanted in Bukhansan National Park. The actual vegetation of the surveyed site was classified into eight plant communities and crop land, etc. Substitutional forest were classified into five plant communities; Quercus mongolica community, Q. mongolica-Pinus densiflora community, Deciduous broadleaf forest, etc. Reforested lands were classified into three forest types: P. koraiensis forest, Robinia pseudoacacia forest, P. rigida forest, etc. The area of DGN 8 consisted of 92.80% in Bukhansan National Park. The replanted plants in Bukhansan National Park was enlisted as 212 taxa, 71 families. The indigenous native among the replanted species were enlisted as 67 taxa(31.6%), 37 families. The exotic plants were enlisted as 145 taxa(68.4%), 58 families. The exotic plants needs to management that for recovery of natural environment, improvement about maintenance of multiplicity and a site of scenery about natural plants in Bukhansan National Park.

Epidemiological Studies of Blast Disease of Rice Plant II. Significance of Differential Distribution of Leaf Lesions at Different Location of Each Tiller as an Inoculum Source of Panicle Blast (수도 도열병의 역학적 연구 II. 이삭 도열병 전염원으로서의 엽위별 병반분포의 의의)

  • Park J.S.;Yu S.H.;Kim H.G.
    • Korean journal of applied entomology
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    • v.22 no.4 s.57
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    • pp.277-282
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    • 1983
  • Number and percentage of diseased area of leaf blast lesions formed on different leaf location were mostly distributed from the flag leaf(n-1) to the 3rd leaf from the top(n-3) in Tongil line rice varieties and on the 2nd leaf from the top(n-2) in Japonica type rice varieties. Especially leaf lesions of Nopung which was more susceptible to leaf blast among Ton1 line rice varieties were mostly distributed on flag leaf. Relation between the degree of lesion distribution and level of fertilizer was more clear with an increase of fertilizer quantity. Leaf blast lesions of rice varieties were generally distributed from the flag leaf to the with leaf from the top but mainly those at flag leaf and the 2nd leaf from the top were found to be most responsible for inoculum source of panicle blast after booting stage. Increase of the conidia formation was resulted from fluctuation of temperature$(24^{\circ}C\~16^{\circ}C)$ in low temperature range after booting stage and many inoculum sources were supplied on panicles until the end of September without impeding dispersal from leaf blast lesions as an inoculum source of panicle blast.

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An Empirical Study on Asymmetric Price Transmissions in the Distribution Channels of Fisheries Market (수산물 시장의 유통단계별 가격전달의 비대칭성에 관한 실증 분석)

  • Lee, Jung-Mi;Kim, Ki-Soo
    • The Journal of Fisheries Business Administration
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    • v.41 no.3
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    • pp.59-78
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    • 2010
  • This paper tries to apply the asymmetrical price transmission(APT) behavior observed in the agricultural industry to supply chains of the domestic fishery industry by a statistical manner. The fore mentioned asymmetrical price transmission refers to when price movements in the later stage of the supply chain do not move in a normal or symmetrical manner corresponding to price movements in the earlier stage of the supply chain. Therefore, when the earlier stage price increase and the later stage price increases to a larger degree, it is called positive(+) asymmetry and the opposite behavior is called negative(-) asymmetry. The study examines the data from domestic producers of three fresh fish types, hairtail, mackerel, and cuttlefish, and tries to examine the price asymmetry between the producer or farm, wholesaler, and retail prices via an APT test utilizing unit root, cointegration, and error correction model. The study found, hairtail wholesale and retail pricing bas a negative asymmetric relationship while mackerel has a negative asymmetric pricing relationship at the producer and retail levels of the supply chain. In the case of cuttlefish, all levels of the supply chain showed negative asymmetrical behavior in the supply chain price transmission, meaning the earlier stage price changes are more rapidly and greatly inputted in the later stage of the supply chain pricing. We believe that the reason why the analysis results show negative price asymmetry is due to the uniqueness of fishery products having an important variable such as freshness. If price increases are greater and quicker than price decreases, then consumer demand, which is sensitive to price increases will decrease and subsequently result in the increase of inventory levels, reducing profits for retailers. Also, frozen hairtail, mackerel, and cuttlefish will act as substitute goods to fresh fishery products. Therefore, fresh fishery products have a high demand of price elasticity. When prices increase, demand quickly decreases. Therefore the profit of wholesalers and retailers to decrease, I think this is the main reason of APT in the supply chain of Korea' s fisheries industry.

Development of the Korean Version of the Social Functioning Scale in the Schizophrenics : A Study on the Reliability and Validity (정신분열병 환자의 한국어판 사회기능척도 개발 : 신뢰도 및 타당도 연구)

  • Kim, Chul-Kwon;Lee, Ji-Ah
    • Korean Journal of Biological Psychiatry
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    • v.16 no.2
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    • pp.76-111
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    • 2009
  • Objectives : The purpose of this study was to develop the Korean version of the Social Functioning Scale (KSFS) in the patients with schizophrenia. Methods : KSFS was administered to 90 schizophrenic patients and 80 their parents and 90 normal controls for examining the reliability and validity. Results : Data analysis showed statistically significant reliabilities and validities of KSFS. The test-retest reliability, rater vs. self-report reliability, and internal consistency for total scores of KSFS were 0.93, 0.44 and 0.94 respectively. Evidence for discriminant validity of KSFS comes from the results that the mean scores of schizophrenic patients were significantly higher than those of normal controls. Construct validity was assessed by calculating the 7 inter-areas correlations of the KSFS, and all areas were statistically significant. Significant correlations between the total scores of KSFS and those of SOFAS lend support for the concurrent validity of this instrument. Factor analyses were performed and two factors were extracted accounting for 63.7% of the variance. Sensitivity was assessed indirectly via the distribution and range of scores on the SFS. The normal control group showed a distribution around a higher mean with a moderate positive skew. Conclusion : KSFS was found to be a valid, reliable, and sensitive instrument which can be used to evaluate the degree of social functioning in the patients with schizophrenia.

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Genetic Diversity and Phylogenetic Relationships among Microsporidian Isolates from the Indian Tasar Silkworm, Antheraea mylitta, as Revealed by RAPD Fingerprinting Technique

  • Hassan, Wazid;Nath, B. Surendra
    • International Journal of Industrial Entomology and Biomaterials
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    • v.29 no.2
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    • pp.169-178
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    • 2014
  • In this study, we investigated genetic diversity of 22 microsporidian isolates infecting tropical tasar silkworm, Antheraea mylitta collected from various geographical forest locations in the state of Jharkhand, India, using polymerase chain reaction (PCR)-based marker assay: random amplified polymorphic DNA (RAPD). A type species, NIK-1s_mys was used as control for comparison. The shape of mature microsporidians was found to be oval to elongate, measuring 3.80 to $5.10{\mu}m$ in length and 2.56 to $3.30{\mu}m$ in width. Of the 20 RAPD primers screened, 16 primers generated reproducible profiles with 298 polymorphic fragments displaying high degree of polymorphism (97%). A total of 14 RAPD primers produced 45 unique putative genetic markers, which were used to differentiate the microsporidians. Calculation of genetic distance coefficients based on dice coefficient method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was conducted to unravel the genetic diversity of microsporidians infecting tasar silkworm. The similarity coefficients varied from 0.059 to 0.980. UPGMA analysis generated a dendrogram with four microsporidian groups, which appear to be different from each other as well as from NIK-1s_mys. Two-dimensional distribution based on Euclidean distance matrix also revealed considerable variability among different microsporidians identified from the tasar silkworms. Clustering of few microsporidian isolates was in accordance with the geographic origin. The results indicate that the RAPD profiles and specific/unique genetic markers can be used for differentiating as well as to identify different microsporidians with considerable accuracy.

Construction of the Airborne Gravity Based Geoid and its Evaluation (항공중력기반 지오이드 모델 구축 및 검증)

  • Lee, Ji-Sun;Kwon, Jay-Hyoun;Lee, Bo-Mi;Hong, Chang-Ki
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.2
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    • pp.159-167
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    • 2009
  • To obtain the gravity data with consistent quality and good distribution over Korea, to overcome the difficulties in constructing precision geoid from biased distribution of ground data, to resolve the discrepancy between the ground and ocean gravity data, an airborne gravity survey was conducted from Dec. 2008 to Jan. 2009. The data was measured at the average flying height of 3,000m and the data with cross-over error of 2.21mGal is obtained. The geoid constructed using this airborne gravity data shows the range of 9.34 $\sim$ 33.88m. Comparing the geoid with respect to the GPS/levelling data, a precision of 0.145m is obtained. After fitting, the degree of fit to GPS/levelling data was calculated about 5cm. It was found that there exists large biases in the area of south-western and northern part of the peninsular which is considered to be the effect of distorted vertical datum in Korea. Thus, more investigation on vertical datum would be needed in near future.

A Study on the Effectiveness Verification of Construction CRM systems (건설 CRM 시스템 효과검증에 관한 연구)

  • Cho, Kyoung-Rin;Hwang, Ug-Sun;Kim, Yong-Su
    • Korean Journal of Construction Engineering and Management
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    • v.8 no.4
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    • pp.137-145
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    • 2007
  • Purpose of this study is to analyze degrees of oral transmission, customer satisfaction, and subscription customer's re-visitation to grasp effectiveness of CRM of construction company. Brand recognition, customer satisfaction, and customer loyalty can be made to improve by CRM of construction company. Ultimately, this study is intended to improve management achievement by increasing total sales and reducing expense. 175 distribution customers and subscription customers participate in the final analysis for this study. In terms of service quality factors, state of facility, trust, response, conviction and sympathy are measured. In terms of effectiveness, customer satisfaction, oral transmission, and customer's re-visitation are measured. Considering these things, CRM of construction company can improve oral transmission, satisfaction, re-visitation of distribution customers and subscription customers. CRM of construction company can be utilized as a competitive means for management and contribute to improving management achievement in the long run. Through examining actual effectiveness of CRM of construction company in this study, it can be thought that necessity and possibility of CRM of construction company should be recognized and CRM of construction company should be developed further.

Error Rate Performance of FH/MFSK Signal with Partial-Band Interference in m-distribution Fading Environment (m-분포 페이딩 환경하에서 부분대역 간섭을 받는 FH/MFSK신호의 오율특성)

  • 강희조;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.11
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    • pp.1320-1331
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    • 1992
  • The error rate equation of FH/MFSK signal of repeated diversity received over m-distribution fading channel with partial-band interference has been derived and the error rate has been evaluated to show in figures as a function of signal to noise ratio, signal to interference ratio, fading figure, repeated number, partial-band interference fraction and power correlation coefficient between signal and interference. In this paper, we assumed that repeated diversity technique is used in transmitter against fading occurred in mobile radio channel. By comparing the error rate performance in diversity against fading and the obtainable degree of improvement of error performance with diversity technique has been found out. From the result, it is known that error rate performance deteriorates more as $\rho$ becomes small i.e., the partial-band interference gives more effect on error performance than full-band interference. Also when the values of $E_b/N_1$ and $\rho$ are small. as depth of fading diversity technique.

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