• Title/Summary/Keyword: Nature frequency

Search Result 572, Processing Time 0.027 seconds

Population Characteristics of Echinosophora koreensis (Nakai) Nakai, a Endemic Plants in Korea (한반도 특산식물 개느삼의 개체군 특성)

  • Kim, Sodam;Moon, Ae-Ra;An, Jong-Bin;Jung, Ji-Young;Park, Wan-Geun;Son, Sungwon
    • Korean Journal of Environment and Ecology
    • /
    • v.34 no.1
    • /
    • pp.18-26
    • /
    • 2020
  • Echinosophora koreensis (Nakai) Nakai an endemic plant with limited distribution in some parts of the Korean Peninsula, is designated as "Endangered" species on the IUCN Red List. The species is under the threat of deterioration in nature due to various environmental changes causing loss of natural habitats. We investigated the distribution pattern and population structure of E. koreensis to serve as a basic reference for identifying the dynamics and persistence of natural populations of this species in the future. To determine the characteristics of the E. koreensis population, we laid two to three large plots sized 20m×30m on the ridgeline as the reference in Yanggu, Chuncheon, and Hongcheon and laid four to seven small quadrats sized 1m×1m on the transect. A total of 530 plots were laid, 10 each at 2m interval, to measure the number of the stems, the number of fruiting, height, and other factors. The collected distribution information was compared with the existing IUCN assessed categories by applying IUCN Red List ver 3.1 Criteria B. The average population density of the three surveyed areas was 3.47 stem/㎡; the density of each area was 3.95 stems/㎡ in Yanggu, 3.37 stems/㎡ in Chuncheon, and 2.87 stems/㎡ in Hongcheon. The number of fruiting per stem was 0.0038, indicating only 7 fruits out of 1,837 stems and that vegetative reproduction is likely to be more dominant than sexual reproduction. The distribution tendency of population density in the small plots in three surveyed areas showed that the density of E. koreensis tended to decrease toward the center of the forest with low crown openness and around the mountain ridge with high crown openness. It indicated that the quantity of light could be a very important factor for the growth of individuals of this species. The analysis of the heights of individuals present in the surveyed plots showed a range of 2.3 ~ 68.5cm and an average of 20.1cm. An analysis on the stage-structure of the E. koreensis population based on the sieve height found that the appearance frequency decreased with increasing height above 15 ~ 20cm and that the percentage of individuals lower than 10cm, which were presumed to be seedlings, was severely low, indicating a necessity of study on the population sustainability based on the monitored data. The occupied area calculated with the collected species distribution information was 200㎢, indicating the EN category according to the IUCN Red List Reference B.

Epidemiologic Investigation for the Etiology of an Epidemic Ocurred among Animals and Humans in an Isolated Island, Korea(I) (신안군(新安郡) 낙도(落島)에서 발생(發生)한 괴질(怪疾)의 원인(原因)에 관한 역학적(疫學的) 조사(調査)(I))

  • Kim, J.S.;Heo, Y.;Yoon, H.Y.;Lee, W.Y.
    • Journal of Preventive Medicine and Public Health
    • /
    • v.22 no.2 s.26
    • /
    • pp.290-301
    • /
    • 1989
  • This is preliminary report on anthrax epidemic occurred in an island with about 100 residents. Since 1982 there had been sudden deaths among all kinds of domestic animals including cattle, dogs, ducks, chicken and goat but only a few among cats in an isolated island about three hours distance away by ferry boat from Mokpo city. From 1986 through 1988 nine human deaths and four patients occurred, which made the government intervene for investigation on June 25 1988. The epidemiological investigation consisted of interview survey and medical examination, medical record analysis, laboratory work to isolate the pathogens under the direction of hypothesis derived from the study and further confirmation of the pathogens by international institute. The summarized results are as followings: 1. According to the interview survey there were many deaths among domestic animals usually in cold and dry season such as January through March and September through November; 36 heads of cattle leaving one head, more than 40 hogs(all), hundreds of chicken leaving few alive, goats that had taken home from mountain and two or three cats out of around 40 had sudden deaths from 1982 till 1985, when the residents stopped to purchase and take them into the island anymore. Also there were eleven persons who had experienced the similar syndrome complex to those of admitted and expired patients and four of them revealed typical chest X-ray findings; from one of these four patients(Rho) B. anthracis is isolated. 2. Medical record on patients who had been admitted, showed common characteristics of the disease course. On admission they had either gastrointestinal or upper respiratory infection symptoms which invariably progressed to septicemic nature with pulmonary interstitial infiltration and mediastinal widening/bulging, and then to deadly acute respiratory distress syndrome. At the end stage chest X-ray revealed multiple bullous emphysema. One of another characteristics was oral ulceration with bleeding occurred in about 50% of the patients. Laboratory test results in common were leukocytosis with left shift and abnormal liver and kidney functions, particularly at the later stage of the illness. 3. Epidemiological characteristics was striking in that both mortality and incidence rates were high: the mortality rate was 8.7% average, male being three times higher than females but there was no distictive clustering by age group. The incidence rate for both sexes was 28.2% and there was no sex difference although a tendency of higher incidence among older ages was noticed. The highest mortality and incidence were observed in Won village where the first death of animal occurred and with the highest frequency among three villages of the island. 4. Among twelve bacilli species isolated from various specimens, two strains, one from patient and the other from soil where the recently died cow is hurried, were confirmed as B. anthracis by Pasteur Institute and CDC of USA(strain from soil). CDC reported that the strain did not produce capsule in bicarbonate media but reacted with the bacteriophage and one of five sera taken from the patients. Mode of transmission as well as incubation period of the agent has not been established yet, which needs further investigation in relation to the antigenic structure of the variant when it is confirmed.

  • PDF

Factors Influencing on the Cognitive Function in Type 2 Diabetics (2형 당뇨병 환자의 인지 기능에 영향 미치는 인자)

  • Goh, Dong Hwan;Cheon, Jin Sook;Choi, Young Sik;Kim, Ho Chan;Oh, Byoung Hoon
    • Korean Journal of Psychosomatic Medicine
    • /
    • v.26 no.1
    • /
    • pp.59-67
    • /
    • 2018
  • Objectives : The aims of this study were to know the frequency and the nature of cognitive dysfunction in type 2 diabetics, and to reveal influencing variables on it. Methods : From eighty type 2 diabetics (42 males and 38 females), demographic and clinical data were obtained by structured interviews. Cognitive functions were measured using the MMSE-K (Korean Version of the Mini-Mental State Examination) and the Korean Version of the Montreal Cognitive Assessment (MoCA-K) tests. Severity of depression was evaluated by the Korean Version of the Hamilton Depression Rating Scale (K-HDRS). Results : 1) Among eighty type 2 diabetics, 13.75% were below 24 on the MMSE-K, while 38.8% were below 22 on the MoCA-K. 2) The total scores and subtest scores of the MoCA-K including visuospatial/ executive, attention, language, delayed recall and orientation were significantly lower in type 2 diabetics with cognitive dysfunction (N=31) than those without cognitive dysfunction (N=49) (p<0.001, respectively). 3) There were significant difference between type 2 diabetics with and those without cognitive dysfunction in age, education, economic status, body mass index, duration of diabetes, total scores of the K-HDRS, the MMSE-K and the MoCA-K (p<0.05, respectively). 4) The total scores of the MoCA-K had significant correlation with age, education, body mass index, family history of diabetes, duration of diabetes, total scores of the K-HDRS (p<0.05, respectively). 5) The risks of cognitive dysfunction in type 2 diabetics were significantly influenced by sex, education, fasting plasma glucose and depression. Conclusions : The cognitive dysfunction in type 2 diabetics seemed to be related to multiple factors. Therefore, more comprehensive biopsychosocial approaches needed for diagnosis and management of type 2 diabetes.

Development of Agent-based Platform for Coordinated Scheduling in Global Supply Chain (글로벌 공급사슬에서 경쟁협력 스케줄링을 위한 에이전트 기반 플랫폼 구축)

  • Lee, Jung-Seung;Choi, Seong-Woo
    • Journal of Intelligence and Information Systems
    • /
    • v.17 no.4
    • /
    • pp.213-226
    • /
    • 2011
  • In global supply chain, the scheduling problems of large products such as ships, airplanes, space shuttles, assembled constructions, and/or automobiles are complicated by nature. New scheduling systems are often developed in order to reduce inherent computational complexity. As a result, a problem can be decomposed into small sub-problems, problems that contain independently small scheduling systems integrating into the initial problem. As one of the authors experienced, DAS (Daewoo Shipbuilding Scheduling System) has adopted a two-layered hierarchical architecture. In the hierarchical architecture, individual scheduling systems composed of a high-level dock scheduler, DAS-ERECT and low-level assembly plant schedulers, DAS-PBS, DAS-3DS, DAS-NPS, and DAS-A7 try to search the best schedules under their own constraints. Moreover, the steep growth of communication technology and logistics enables it to introduce distributed multi-nation production plants by which different parts are produced by designated plants. Therefore vertical and lateral coordination among decomposed scheduling systems is necessary. No standard coordination mechanism of multiple scheduling systems exists, even though there are various scheduling systems existing in the area of scheduling research. Previous research regarding the coordination mechanism has mainly focused on external conversation without capacity model. Prior research has heavily focuses on agent-based coordination in the area of agent research. Yet, no scheduling domain has been developed. Previous research regarding the agent-based scheduling has paid its ample attention to internal coordination of scheduling process, a process that has not been efficient. In this study, we suggest a general framework for agent-based coordination of multiple scheduling systems in global supply chain. The purpose of this study was to design a standard coordination mechanism. To do so, we first define an individual scheduling agent responsible for their own plants and a meta-level coordination agent involved with each individual scheduling agent. We then suggest variables and values describing the individual scheduling agent and meta-level coordination agent. These variables and values are represented by Backus-Naur Form. Second, we suggest scheduling agent communication protocols for each scheduling agent topology classified into the system architectures, existence or nonexistence of coordinator, and directions of coordination. If there was a coordinating agent, an individual scheduling agent could communicate with another individual agent indirectly through the coordinator. On the other hand, if there was not any coordinating agent existing, an individual scheduling agent should communicate with another individual agent directly. To apply agent communication language specifically to the scheduling coordination domain, we had to additionally define an inner language, a language that suitably expresses scheduling coordination. A scheduling agent communication language is devised for the communication among agents independent of domain. We adopt three message layers which are ACL layer, scheduling coordination layer, and industry-specific layer. The ACL layer is a domain independent outer language layer. The scheduling coordination layer has terms necessary for scheduling coordination. The industry-specific layer expresses the industry specification. Third, in order to improve the efficiency of communication among scheduling agents and avoid possible infinite loops, we suggest a look-ahead load balancing model which supports to monitor participating agents and to analyze the status of the agents. To build the look-ahead load balancing model, the status of participating agents should be monitored. Most of all, the amount of sharing information should be considered. If complete information is collected, updating and maintenance cost of sharing information will be increasing although the frequency of communication will be decreasing. Therefore the level of detail and updating period of sharing information should be decided contingently. By means of this standard coordination mechanism, we can easily model coordination processes of multiple scheduling systems into supply chain. Finally, we apply this mechanism to shipbuilding domain and develop a prototype system which consists of a dock-scheduling agent, four assembly- plant-scheduling agents, and a meta-level coordination agent. A series of experiments using the real world data are used to empirically examine this mechanism. The results of this study show that the effect of agent-based platform on coordinated scheduling is evident in terms of the number of tardy jobs, tardiness, and makespan.

Management of the Development of Insecticide Resistance by Sensible Use of Insecticide, Operational Methods (실행방식 측면에서 살충제의 신중한 사용에 의한 저항성 발달의 관리)

  • Chung, Bu-Keun;Park, Chung-Gyoo
    • Korean journal of applied entomology
    • /
    • v.48 no.2
    • /
    • pp.123-158
    • /
    • 2009
  • An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

INVESTIGATION OF THE EFFECT OF AN ANTIBIOTIC "P" ON POTATOES ("감자에 대한 항생제(抗生劑) 피마리신의 통계적(統計的) 효과(效果) 분석(分析)")

  • Kim, Jong-Hoon
    • Journal of Korean Society for Quality Management
    • /
    • v.5 no.2
    • /
    • pp.59-120
    • /
    • 1977
  • An antibiotic 'P', which is one of the products of the Gist Brocades N. V. is being tested by its research department as fungicide on seed-potatoes. For this testing they designed experiments, with two control groups, one competitor's product, eight formulations of the antibiotic to be tested in different concentrations and one mercury treatment which can not be used in practice. The treated potatoes were planted in three different regions, where bifferent conditions prevail. After several months the harvested potatoes are divided in groups according to their diameter, potato illness is analysed and counted. These data were summarised in percentage and given to us for Analysis. We approached and analysed the data by following methods: a. Computation of the mean and standard deviation of the percenage of good results in each size group and treatment. b. Computation of the experimental errors by substraction of each treatment mean from observed data. c. Description of the frequency table, plotting of a histogram and a normal curve on same graph to check normality. d. Test of normality paper and chi-sqeare test to check the goodness of fit to a normal curve. e. Test for homogeneity of variance in each treatment with the Cochran's test and Hartley's test. f. Analysis of Variance for testing the means by one way classifications. g. Drawing of graphs with upper and lower confidence limits to show the effect of different treatments. h. T-test and F-test to two Control mean and variance for making one control of Dunnett's test. i. Dunnett's Test and calculations for numerical comarision of different treatments wth one control. In region R, where the potatoes were planted, it was this year very dry and rather bad conditions to grow potatoes prevailed during the experimental period. The results of this investigation show us that treatment No.2, 3 and 4 are significantly different from other treatments and control groups (none treated, just like natural state). Treatment no.2 is the useless mercury formulation. So only No. 3 and 4, which have high concentrations of antibiotic 'P', gave a good effect to the potatoes. As well as the competitors product, middle and low concentrated formulations are not significantly different from control gro-ups of every size. In region w, where the potatoes got the same treatments as in region R, prevailed better weather conditions and was enough water obtainable from the lake. The results in this region showed that treatment No. 2, 3, 4, and 5 are Significantly different from other treatments and the control groups. Again No.2 is the mercury treatmentin this investigation. Not only high concentrated formulation of antibiotic 'P', but also the competitor's poroduct gave good results. But, the effect of 'P', was better than the competitors porduct. In region G, where the potatoes got the same treatments as in the regions R and w. and the climate conditions were equal to region R, the results showed that most of the treatments are not significantly different from the control groups. Only treatment no. 3 was a little bit different from the others. but not Significantly different. It seems to us that the difference between the results in the three regions was caused by certain conditions like, the nature of the soil the degres of moisture and hours of sunshine, but we are not sure of that. As a conclusion, we can say that antibiotic 'P' has a good effect on potatoes, but in most investigations a rather high concentration of 'P' was required in formulations.

  • PDF

A Study on the Characteristics of Each Section Based on Visitor's Satisfactions of the Dulegil in Bukhansan National Park (북한산국립공원 둘레길 탐방객 만족도에 따른 구간별 특성화 연구)

  • Han, Bong-Ho;Choi, Jin-Woo;Hur, Ji-Yeon;Kim, Sun-Hee;An, Kyung-Jin
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.41 no.2
    • /
    • pp.69-82
    • /
    • 2013
  • The purpose of this study is to evaluate the effect of Dulegil in Bukhansan National Park in dispersing peak climbing hikers, characterize each section of Dulegil and suggest ideas of improvement. This study was conducted based on the survey completed by visitors in all 21 sections of Dulegil. After the construction of Dulegil, the number of visit to Dulegil grew and it was analyzed that Dulegil attracted new visitors given that the rate of young people(aged 19~30) who visited for the first time was quite high. Regarding the frequency of peak climbing, 7.6% of the respondents said "decreased" and 46.2% said "increased", showing that Dulegil's effect to disperse peak climbing hikers is nominal. Seven qualities were evaluated regarding Dulegil's level of satisfaction. Out of those seven, the quality of recreational place and taking a walk achieved high scores of 3.74 and 3.61 respectively. The quality of culture and history scored the lowest with 3.09. The analysis on the characteristic of each section of Dulegil, reason of visit, and the visitors' level of satisfaction showed that Dulegil is now regarded as a place where they can improve their health through light exercise and walking. In addition, a positive effect can be expected for a long time since there are different ways of utilizing the resources of the National Park, such as getting in touch with nature, preserving ecology, learning history and enjoying beautiful landscapes. If infrastructure and programs specific to each section of Dulegil were improved in a long-term perspective, it would be effective to encourage peak climbers and enjoy the lower parts of the mountain.

Physical knowledge in children: Children's developing understanding of object motion (아동의 물리지식: 물체의 운동에 대한 아동의 이해와 발달)

  • Park Sunmi
    • Korean Journal of Cognitive Science
    • /
    • v.15 no.4
    • /
    • pp.31-47
    • /
    • 2004
  • This study was carried out to examine the development of physical knowledge in children. Eighty children aged 3- to 11-year-old and 16 adults were participated in this study. Participants' knowledge about failing, sliding and sinking/floating objects was investigated to understand what kind of knowledge they had, whether their knowledge was organized as theory and what was the nature of the developmental change in physical knowledge. Results showed that, for falling object task children of all age had correct knowledge about object's falling phenomena. However, there were age differences in children's understanding of the cause of object's falling. As the children's age decreased, the frequency of explanation referring to the absence of supper rather than the gravity as the cause of falling phenomena increased. For the sliding object task, children of all age could predict the motion of sliding object correctly. But only a few 9- and 11-year-old children could understand the effect of object weight and relations between gravity, frictional force and their interactions. Children under age 7 showed no evidence of possessing these knowledge. For sinking or floating object task, children of all age and even adults showed difficulties in understanding the sinking or float phenomena per se. For the cause of these phenomena although a few 9- and 11-year-old children referred to buoyancy as the cause, they had no correct knowledge about the buoyancy. This was also true for the adults. As a conclusion, the results of this study suggested that, not 3, but as young as 5-year-old children's physical knowledge exited as a form of naive theory in terms of their use as a causal devise in explaining the cause of object motion. However, even the theory of 9- and 11-year-old children was lack of the abstractness and coherence, which were also important characteristics of a theory. Finally, developmental change in physical knowledge proceeded toward more frequent and consistent use of physical knowledge as causal device and more abstract and coherently organized theory.

  • PDF

Epidemiologic Investigation of an Outbreak of Shigellosis in Kyongju, Korea (1998년 경주시 한 초등학교 학생과 인근 주민에서 발생한 세균성이질)

  • Jung, Cheol;Bae, Geun-Ryang;Hur, Yeong-Joo;Lee, Sang-Won;Jeong, Eun-Kyeong;Lim, Hyun-Sul
    • Journal of Preventive Medicine and Public Health
    • /
    • v.33 no.1
    • /
    • pp.1-9
    • /
    • 2000
  • Objectives : This study was carried out to investigate the sources of infection and modes of transmission of an outbreak of shigellosis that occurred among pupils of 'M' primary school and residents near the school in Kyongju from Sept. 24 to Oct. 24, 1998. Methods : The subjects who completed a questionnaire and a rectal swab for microbiologic examinations were 1,534 persons (781 males, 753 females), including 469 pupils of 'M' primary school (268 males, 201 females). Bacteriological examinations of underground water and simple piped water were done. Results : The attack rate of diarrhea was 28.7% in the subjects from Sept.24 to Oct. 24, 1958. There was no difference in attack rate of diarrhea by gender, but it was significantly higher in the pupils of 'M' primary school than others (p<0.01). The attack rate of diarrhea by resident areas was no different to the pupils of 'M' primary school, but was significantly higher in the residents of Mohwa 2 Ri except pupils that 'M' primary school is located in (p<0.01). The distribution of date of onset revealed the exposure date to be Sept, 22 and 23 in consideration of incubation periods and common source outbreak followed propagative spread in the epidemic curve. The major characteristics of diarrhea were watery (89.1%) in nature, $1\sim3$ days (72.5%) in duration, $2\sim3$ times (63.9%) in frequency. The clinical symptoms among the diarrheal cases included abdominal pain (74.1%), fever (56.4%), headache (55.9%), chill (40.4%) and tenesmus (31.4%). Conclusions : The source of infection was estimated to be contaminated underground water and simple piped water caused by leakage from the cess pool. It is highly necessary that the management of drinking water and cess fools should be done thoroughly.

  • PDF

A Characteristics of Visual Narrative Expression in Garden Design - Focused on the Taehwagang Garden Show 2018 - (정원디자인에 나타난 시각적 서술의 표현특성 - 2018 태화강 정원박람회 작품을 대상으로 -)

  • Kwon, Jin-Wook
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.37 no.3
    • /
    • pp.108-118
    • /
    • 2019
  • Appreciating gardens in garden show has its meaning in appreciating concepts and ideas of artists, hidden inside of garden, as formative arts, as well as the beauty of the nature. This study is aimed to understand the intension of artists in visual expression through formative media in the gardens by assessing structure of visual narrative in the space with 20 artworks among the ones presented in 2018 Taehwagang Garden Show. The formative structure is delivered as contents and forms through formative media and formative language. Thus, for analysis on the artworks, the researcher assessed expressive characteristics of the media, through visual and space language, that forms the formative structure in the contest of narrative structure expressed in the gardens and findings of the analysis are as follows. First, for intertextuality obtained through media image, most of the artworks delivered message through 'figure image.' This means, the concept is delivered as 'affinity of actual objects' through the media and associated 'meaning and meaning action' are expected. Second, the characteristics of signs to show symbolism in the gardens were categorized into 'icon'. 'index' and 'symbol'. The results showed that most of the artworks expressed common characteristics between image and meaning, using 'icon' and 'symbol'. Third, as space formation components, based on formative principles, the components of 'dominant' and 'subordinate' roles were defined as the key components for meaning delivery. Also, it was understood that 'space configuration with overlapped image' and 'space configuration with transparency' were adopted to strengthen conceptional layers. Forth, for space occupation types, there were mostly central hall type, corridor type and passage space type and for open space type, the entire space area was conceptualized, instead of certain object. The circulation line was defined in the frequency order of circular type, pass type and return type. The study on the expressive characteristics of visual narrative in garden design is meaningful as it could build base data for the method of spatial design for visual development of concepts in the future.