• Title/Summary/Keyword: occurrence pattern

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Analysis of Spatio-temporal Pattern of Urban Crime and Its Influencing Factors (GIS와 공간통계기법을 이용한 시·공간적 도시범죄 패턴 및 범죄발생 영향요인 분석)

  • Jeong, Kyeong-Seok;Moon, Tae-Heon;Jeong, Jae-Hee;Heo, Sun-Young
    • Journal of the Korean Association of Geographic Information Studies
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    • v.12 no.1
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    • pp.12-25
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    • 2009
  • The aim of this study is to analyze the periodical and spatial characteristics of urban crime and to find out the factors that affect the crime occurrence. For these, crime data of Masan City was examined and crime occurrence pattern is ploted on a map using crime density and criminal hotspot analysis. The spatial relationship of crime occurrence and factors affecting crime were also investigated using ESDA (Exploratory Spatial Data Analysis) and SAR (Spatial Auto-Regression) model. As a result, it was found that crimes had strong tendency of happening during a certain period of time and with spatial contiguity. Spatial contiguity of crimes was made clear through the spatial autocorrelation analysis on 5 major crimes. Especially, robbery revealed the highest spatial autocorrelation. However as a autocorrelation model, Spatial Error Model(SEM) had statistically the highest goodness of fit. Moreover, the model proved that old age population ratio, property tax, wholesale-retail shop number, and retail & wholesale number were statistically significant that affect crime occurrence of 5 most major crimes and theft crime. However population density affected negatively on assault crime. Lastly, the findings of this study are expected to provide meaningful ideas to make our cities safer with U-City strategies and services.

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Dominance and Distribution of Weed Occurrence on Onion, Garlic, Potato, and Barley Fields of Gyeongbuk Province (경북지역 양파, 마늘, 감자, 보리밭의 잡초 분포 및 우점 특성)

  • Kim, Sang-Kuk;Shin, Jong-Hee;Park, Sang-Gu;Kim, Se-Jong
    • Weed & Turfgrass Science
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    • v.4 no.2
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    • pp.77-84
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    • 2015
  • We surveyed the distribution pattern of weeds in onion, garlic, potato, and barley fields including 304 sites of Gyeongsangbuk-do. The weeds were summarized as 30 family and 125 species in onion crop field, 29 family and 101 species in garlic field, 30 family 88 species in potato field, finally 27 family and 108 species. Compositae was dominant family (26.4%, 33 species), followed by Polygonaceae (8.8%, 11 species), Cruciferae (8.8%, 11 species) in onion field. Compositae was also dominant family (24.8%, 25 species) in garlic field, it was 22.7% (20 species) in potato field, and it was also 24.1% (26 species) in barley field, respectively. Among these winter crops, major five families were occupied 61.1, 58.4, 58.0 and 57.5% in turn at barley, onion, potato and garlic fields. The PCA-covariance plot analysis for investigation of occurrence pattern of weeds by four winter crop fields revealed that the occurrence pattern of weed species in barley field was distinguished by Alopecurus aequalis var. amurensis, Stellaria alsine var. undulate and Stellaria aquatica.

Occurrence of Weedy Rice as Affected by Cultural Practices

  • Kim, Sang-Yeol;Son, Yang;Ha, Woon-Goo;Park, Sung-Tae;Kim, Soon-Chul
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.2
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    • pp.124-127
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    • 1998
  • Since weedy rice problems have emerged with the recent advent of direct seeding cultivation in Korea, the establishment of effective control strategies for weedy rice is considered to be one of the urgent issues to be solved for widely practiced direct seeding rice cultivation. A three year experiment was conducted to investigate the occurrence pattern of weedy rice in four different rice cultivation practices: high ridged dry seeding, wet drill seeding, water seeding, and machine transplanting. The highest weedy rice occurrence of 11.0% was observed in high ridged dry seeding practice followed by 9.6% in wet drill seeding, 6.4% in water seeding practice, and 0.2% in machine transplanting practice, respectively. The same trend was observed when we examine the occurrence of contamination of panicle and rice grain by weedy rice. More contamination was observed in high ridged dry seeding than any other practices. It was also found that the possible emergence depths from the soil surface was deeper in both in ridged dry seeding and wet drill seeding practice (0-5 cm from the soil surface) than those in water seeding (0-4 cm), and machine transplanting practice (0-3 cm). The highest yield reduction of 19.5% was observed in high ridged dry seeding practice followed by 13.0% in wet drill seeding, 6.3% in water seeding practice. The reduction may have occurred to the competition between weedy rice and cultivated rice, These findings suggest that among the four cultural practices examined, the machine transplanting practice is the most effective method to control and reduce the weedy rice occurrence and weedy rice seed in soil.

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Characteristics and Co-Occurrence Patterns of Fragrance Allergens in Consumer Chemical Products (생활화학제품의 알레르기반응가능 향료성분 함유 현황 및 동시 출현 패턴 조사)

  • Kim, Soomin;Lee, Kiyoung;Lim, Miyoung
    • Journal of Environmental Health Sciences
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    • v.48 no.4
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    • pp.206-215
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    • 2022
  • Background: Fragrance substances in consumer products can cause adverse health effects such as contact allergy. In South Korea, consumer chemical products must list 26 known fragrance allergens on product labels when they contain more than 0.01%. Fragrance substances are mostly used in combination, so co-exposure can occur via use of a consumer chemical product. Co-exposure to fragrance allergens may show a synergistic effect on the human body. Objectives: The aims of the study were to analyze the characteristics of fragrance allergens in consumer chemical products available on public websites and to identify the co-occurrence patterns of fragrance allergens. Methods: The chemicals in 1,443 ingredient disclosures for consumer chemical products were collected through the Ecolife database. The 26 labelled fragrance allergens were identified by category of consumer chemical product. The co-occurrence patterns of the 26 labelled fragrance allergens were analyzed by frequent pattern mining. The unlabelled fragrance allergens presented by European Union Scientific Committee on Consumer Safety were also identified. Results: Consumer chemical products contained an average of 5.3±4.2 substances among the 26 labelled fragrance allergens. More than 85% of air fresheners, deodorizing agents, and fabric softeners contained at least one of the 26 labelled fragrance allergens. The most frequently contained fragrance allergens were limonene (50.5%), linalool (49.9%), hexyl cinnamal (34.0%), and citronellol (28.3%). 16.7% of consumer chemical products showed a co-occurrence of limonene, linalool, hexyl cinnamal, and citronellol. Thirty-eight unlabelled fragrance allergens were found in the consumer chemical products, with hexamethylindanopyran (25.2%) being the most frequently contained substance. Conclusions: The characteristics and co-occurrence patterns of 26 labelled fragrance allergens would be useful information for the management of co-exposure to fragrance allergens in consumer chemical products. It is necessary for attention to be paid to unlabelled fragrance allergens.

Variation in the Pattern of Isoperoxidase Bands in the Four Parts of Lespedeza cyrtobotrya Miq. (참싸리 부위별(部位別) 과산화(過酸化) 동위효소형(同位酵素型)의 변이(變異))

  • Han, Young Chang
    • Journal of Korean Society of Forest Science
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    • v.30 no.1
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    • pp.42-49
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    • 1976
  • In order to study the variations of isoperoxidases of four parts of L. cyrtobotrya, leaves, secondary phloem, fibrous root, ovary were collected on september 29, 1975, respectively from 12 individuals which were planted in the compound of Institute of Forest Genetics, suwon, Korea. No variation of isoperoxidases appeared among the same parts which were collected from the same individual. There was a great variation in the pattern of isoperoxidase band among the 12 individuals in leaves, secondary phloem, fibrous root, and ovary. Regarding to the common occurrence band, the number was 7 in the leaves, secondary phloem, and fibrous root, while 35 bands were appeared in the ovary part. These was a great variation of occurrence band in four parts of Lespedeza. But the number of band in the parts of the Lespedeza was 4.50-5.16 on average, on the other hand there was no significant difference. No variation was observed in the activity of isoperoxidase in leaves. On the other hand, there was small varation in the secondary phloem, fibrous root and ovary.

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A Study on Technology Forecasting based on Co-occurrence Network of Keyword in Multidisciplinary Journals (다학제 분야 학술지의 주제어 동시발생 네트워크를 활용한 기술예측 연구)

  • Kim, Hyunuk;Ahn, Sang-Jin;Jung, Woo-Sung
    • Journal of the Korean Operations Research and Management Science Society
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    • v.40 no.4
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    • pp.49-63
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    • 2015
  • Keyword indexed in multidisciplinary journals show trends about science and technology innovation. Nature and Science were selected as multidisciplinary journals for our analysis. In order to reduce the effect of plurality of keyword, stemming algorithm were implemented. After this process, we fitted growth curve of keyword (stem) following bass model, which is a well-known model in diffusion process. Bass model is useful for expressing growth pattern by assuming innovative and imitative activities in innovation spreading. In addition, we construct keyword co-occurrence network and calculate network measures such as centrality indices and local clustering coefficient. Based on network metrics and yearly frequency of keyword, time series analysis was conducted for obtaining statistical causality between these measures. For some cases, local clustering coefficient seems to Granger-cause yearly frequency of keyword. We expect that local clustering coefficient could be a supportive indicator of emerging science and technology.

Heterogeneous Face Recognition Using Texture feature descriptors (텍스처 기술자들을 이용한 이질적 얼굴 인식 시스템)

  • Bae, Han Byeol;Lee, Sangyoun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.14 no.3
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    • pp.208-214
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    • 2021
  • Recently, much of the intelligent security scenario and criminal investigation demands for matching photo and non-photo. Existing face recognition system can not sufficiently guarantee these needs. In this paper, we propose an algorithm to improve the performance of heterogeneous face recognition systems by reducing the different modality between sketches and photos of the same person. The proposed algorithm extracts each image's texture features through texture descriptors (gray level co-occurrence matrix, multiscale local binary pattern), and based on this, generates a transformation matrix through eigenfeature regularization and extraction techniques. The score value calculated between the vectors generated in this way finally recognizes the identity of the sketch image through the score normalization methods.

Comparison on the Time of Occurrence of Major Rice Insect Pests Based on Growing Degree Day in Northern Part of Korean Peninsula (북방농업지대에서 유효적산온도를 이용한 벼 해충의 발생시기 비교)

  • Kim, Soon-Il;Uhm, Ki Baik;Jin, Da-Yong;Park, Hyung Man
    • Korean journal of applied entomology
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    • v.58 no.3
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    • pp.239-249
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    • 2019
  • This study was carried out to compare on the time of occurrence of 6 major rice insect pests [Lissorhoptrus oryzophilus Kusche, Oulema oryzae Kuwayama, Sogatella furcifera (Horvath), Nilaparvata lugens Stal., Cnaphalocrocis medinalis (Guenee), Mythimna separata Walker] in northern part of the Korean peninsula. Using growing degree days of the insects, we evaluated the number of occurrence generations and the time of occurrence. Over-wintering insects such as L. oryzophilus and O. oryzae showed different occurrence periods in northern regions. The occurrence period of the first generation adults was later in northeast regions than in Korean middle regions and more later both in northern alpines and in northern parts of east sea. In addition, the first adults of S. furcifera, N. lugens, C. medinalis, and M. separata occurred between June and early August. However, from late August to September, these insects showed the different occurrence periods in northern regions. Especially, the second adults of N. lugens were not occurred and the second to third generation adults of S. furcifera, C. medinalis, and M. separata showed similar occurrence properties. Based on these properties, the occurrence of major rice insect pests will be less in northeast regions, northern regions of east sea, northern inlands, and northern alpines of the Korean peninsula. However, comparing with their occurrences in northern regions of Gyenonggi and Gangwon provinces, the rice insect pests may show similar occurrence pattern in mid-korean mountains except for pyunggang and yangduk regions as well as in the southern and northern regions of Suyang-san.

Development of Insect Population Dynamics and Forecast Models: A Case of Chilo suppressalis(Walker) Occurrence in Suwan (해충발생동태 및 예찰모델 개발: 수원에서의 이화명나방 발생 사례)

  • 이준호
    • Korean journal of applied entomology
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    • v.38 no.3
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    • pp.231-240
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    • 1999
  • The long-term tend an pattern changes of Chilo suppressalis(Walker) occurrence in Suwon were analyzed and the forecasting models for spring emergence of C. suppressalis in Suwon were developed. From 1965 to 196, the population dynamics of C. suppressalis in Suwon shows a cyclic fluctuation with one large peak an one small peak, and its periodicity was ca. 36 generations(18 years). C. suppressalis population dynamics in Suwon was characterized as controlled by the endogenous dynamics dictated by the 1st order negative feedback mechanism (fast density dependence). The dynaics mechanism of C. suppressalis populations was not changed although its population density decreased drastically over the years. Using th dta of C. suppressalis spring occurrence in Suwon, forecasting models for spring emergence of C.supressalis were developed based on temperature-dependent development model or degree days. In general, these models well described the C. suppressalis spring emergence pattern in Suwon. Also, forecasting problems in spring moth emergence related with C. suppressalis population dynamics were discussed.

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Characterization and evaluation of response to heat and chilling stress in exotic weeds using chlorophyll a fluorescence OJIP transient

  • Sohn, Soo In;Lee, Yong Ho;Hong, Sun Hee;Kim, Chang Seok;Kim, Myung Hyun;Na, Chae Sun;Oh, Young Ju
    • Korean Journal of Environmental Biology
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    • v.38 no.3
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    • pp.450-460
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    • 2020
  • The occurrence of exotic weeds and their influx into farmlands due to climate change poses many problems. Therefore, it is necessary to generate a prediction model for the occurrence pattern of these exotic weeds based on scientific evidence and devise prevention measures. The photosynthetic apparatus is known as the most temperature-sensitive component of a plant cell and its initial response to temperature stress is to inhibit the activation of photosystem II. This study investigated the potential of OJIP transients in assessing temperature stress in exotic weeds. The four exotic weeds currently flowing into Korean farmlands include Amaranthus spinosus, Conyza bonariensis, Crassocephalum crepidioides, and Amaranthus viridis. These weeds were treated at 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 35℃, and 40℃ and the OJIP curves and JIP parameters were measured and analyzed. The results showed that heat and chilling stress affected the photosystem II(PSII) electron transport of A. spinosus, whereas C. crepidioides and A. viridis were more affected by high-temperature stress than by low-temperature stress. Lastly, C. bonariensis showed resistance to both high and low-temperature stress. The results of this study suggest that OJIP transients and JIP parameters can be used to analyze damage to the photosynthetic apparatus by temperature stress and that they can serve as sensitive indicators for the occurrence pattern of exotic weeds.