• Journal of Wetlands Research
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• v.17 no.2
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• pp.113-117
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• 2015

Even though many researches are conducted for the conservation and restoration of endangered species Menyanthes trifoliata, recently, there is no study on the threatening factors to this plant. This is the first time in Korea to study growth and feeding characteristics of Deilephila elpenor as a threatening factor to Menyanthes trifoliata through an experiment. Experiment was done with 6 Eephant hawk-moth larvae and change of body weight, food preference, and ingestion amount of Bog-bean were investigated. It took 27 days from larva to pupa and maximum body weight of lavae was in the range of 4-7.5g. The food preference sequence of the lavae was Menyanthes trifoliata, Impatiens balsamina, Ampelopsis brevipedunculata var. heterophylla, Parthenocissus tricuspidata. Ingestion model shows the total amount of ingestion by a larva is 11-30g and this amount can be acquired at $0.03-0.08m^2$ of Menyanthes trifoliata pure stand. This study showed Deilephila elpenor as a potential threatening factor and suggests that the conservation and restoration plan of endangered species Menyanthes trifoliata include the control plan of Deilephila elpenor, also.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.312-315
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• 2002

Diagnostic tests often require the determination of cut-off values that discriminate uninfected from infected individuals. The receiver operating characteristic (ROC) curve has been frequently used to attain this purpose and gives a representation of diagnostic accuracy (sensitivity and specificity) of a prediction model when varying the cut-point of a decision rule on a whole spectrum. We have written and tested a visual basic application program in EXCEL for maximum likelihood estimation of a binormal ROC curve, which also computes univariate statistics of a diagnostic test employed. Examples applying for computed tomographic images in radiology and methicillin-resistant Staphylococcus aureus research are given to illustrate this approach. This stand-alone module is available from the first author on request.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.181-186
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• 2004

The current situation of heating and cooling system of the classrooms of our country is rather poor compared not only to those of the developed nation's classrooms but also in case of other buildings such as financial institutions, office compounds. In winter, especially students have been in hatred state with respect to their health due to the fact that the heater is operated by petroleum. Korea has been heavily dependent on foreign nations for the very fact of importing energy in the form of oil or natural gas. So it is important to conserve energy and the picture with respect to energy remains similar till today as it was in long past periods. The purpose of this study is to contribute actively in energy economy and facilitate towards a healthy school life of students and other institutions proving a system of extracting energy from river water and then converting it into heat which can stand as an effective alternate of expensive oil or gas. Installing oil-stove based heating system at classrooms of school could get considerable attentation in several respects. The proposed heat energy could be collected unlimitedly both in time and in amount. The stable and uninterrupted heat energy from river water, optimally utilizing the typical-regional and geographical characteristics has the potential to be long-lasting in duration, cheap in energy economy and beneficial to health as well.

• Journal of Advanced Navigation Technology
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• v.25 no.1
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• pp.40-51
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• 2021

In this paper, the design requirements was produced by analyzing domestic and foreign regulations of the vertical takeoff and landing site required to operate the urban air mobility (UAM) system in Korea and the size of the take-off and landing pads were defined, and the configuration of vertiport was proposed. First, for the metropolitan area with high population density, pilot locations of the vertical take-off and landing site were selected based on the demonstration routes suggested by the Ministry of Land, Infrastructure and Transport and analyzed the characteristics of each location and determined the number of possible installations of vertiport by measuring each site. After that, variables necessary for the operation of the vertical takeoff and landing area were set, and the hourly, daily, monthly aircraft operating cycle, the number of acceptable people, and efficiency were calculated according to the number of simultaneous operation and the number of stand. Finally, using CATIA, the configurations of the virtual vertiport was created by applying the design requirements.

• Journal of Korean Society of Forest Science
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• v.111 no.2
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• pp.224-233
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• 2022

We carried out this study to identify the vegetation structure of Abies nephrolepis Maxim. in the southern region of Gangwon-do. We conducted field investigations in 192 stands (400 m²). We analyzed the importance, value, and species diversity of the stands after classifying community type using the methods of the Z-M School of Phytosociology and two-way indicator species analysis (TWINSPAN). We classified the stand structure of A. nephrolepis into th e A. nephrolepis-Acer pseudosieboldianum community, We classified the A. nephrolepis-Dryopteris crassirhizoma community, as an A. nephrolepis typical community. We identified A. nephrolepis, Quercus mongolica, Betula ermanii, Sorbus commixta, Tilia amurensis, and Acer pseudosieboldianum as having high importance value.

• Korean Journal of Applied Biomechanics
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• v.32 no.4
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• pp.111-120
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• 2022

Objective: This study investigated the effect of pelvic tiltng according to the paralytic side on gait in stroke patients during a 10 m functional movement timed up and go (TUG) test. Method: In this study, gait parameters were measured using a gait analyzer for 20 stroke patients and their gait was analyzed during a 10 m TUG test. For statistical analysis, an independent sample t-test were performed for age, height, and weight among general characteristics of subjects and homogeneity was tested by performing a chi-square test for gender, paralysis side, period of onset, and K-MMSE score. In order to understand the relationship between each variable, Pearson correlation analysis was performed on the variables. Results: First, the right-hand paralyzed group showed correlations in cadence and gait velocity in the up and down tilt of the pelvis, and the left-hand paralyzed group showed correlations in cadence and step length in the anterior and posterior tilt of the pelvis. Second, the tilt of the pelvis was correlated with the Sit to stand, walk forward, walk backwards, turn around at the end point, sit on a chair and the total TUG time in the right hemiplegic group compared to the left hemiplegic group. Conclusion: In this study, a significant correlation was confirmed as a result of gait analysis of right-handed stroke patients divided into a right paraplegic group and a left paraplegic group. In the future, it is suggested that treatment for improving gait of stroke patients should be treated differently for the right and left paralyzed side.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.219-223
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• 2010

It has long been recognized that wild vegetation are sort of improving fitness. Many peoples are now ingesting them instead of the vegetables that are grown in green house. In this regard, Parasenecio firmus, which is considered to be one of the rare species in Korea, has been given a lot of attentions as edible green plants recently. Hence it may be necessary to provide the information people who want to commercially cultivate the plants. Regarding appropriate forest stands that are fit for the cultivation. Firstly, we collected the seeds from 4 natural habitats to find out how many seeds are fully matured in the natural conditions. The quality of the seeds collected were found to be very low. However, it appeared as clear differences when screened seeds were grown in covered seed beds over winter. In this case the germination rate of the seeds was 95%, indicating that there may be no difficulty for mass production of plantlets. Secondly, in the field of planting test in an appropriate cultivating site among 6 of forest stands, those in Pinus koraiensis stand were the highest in survival rate, but somewhat low with those in Quercus mongolica and broad-leaved stands. Thus, it was demonstrated that forest stands dominated with conifer like P. koraiensis are more appropriate for the cultivation of P. firums.

• Journal of Korean Society of Forest Science
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• v.40 no.1
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• pp.1-18
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• 1978

Three Pinus densiflora populations as shown in location map (Fig. 1) were studied in 1977. These succeed the population numbers 10, 11 and 12 after the preceeding populations. Following the previous study methods, 20 trees were chosen from each population and the morphological characteristics such as tree forms, branching habit, needle and wood properties were investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 40 to 45. The growth performances of trees of population 10 and 11 was similar, but 12 seemed to be inferior more or less. 2. The ratios of clear bole length was 0.53 in population 12 as the highest but 0.43 for population 10 as the lowest. 3. The population 12 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown length) 1.65 though the mean branching angle indicates almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between populations as shown in Fig. 3 and 4. 5. No inter-population differences in serration density of needle was shown but significant inter and intra-population and individual differences (within population) in number of stomata rows and resin duct. 6. Population 12 shown 0.119 of resin duct index as the maximum. 7. The pattern of diameter growth, analyses based on the width of 10-year-ring segment unit (for example, the 1st segment denotes the width between pith center and 10th year ring and the 2nd one is from 11th to 20th year ring and so on.), was alike among populations as shown in Fig. 9. 8. No significant differences between population in mean summer wood percentages as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 10 and 11 however vice versa in population 12. 9. The fiber length was increased with the increase of age but no differences between populations as shown in Fig. 12.

• Journal of Korean Society of Forest Science
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• v.44 no.1
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• pp.1-25
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• 1979

Six natural populations of Pinus densiflora S. et Z. as shown in the location map (Flg 1) were studied during 1978. The numerial pouplation codes, 13 to 18. The results of populations 1 to 12 were reported in previous papers. Following the study methods described before, 20 trees were sampled from each population and morpological characteristics such as stem forms, branching habit needle and wood properties investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 36 to 97 of years. The growth performances of trees of population 14. 15 and 18 was similar, but 13, 16, and 17 seemed to be inferior more or less. 2. The ratios of clear bole length were 0.70 in population 18 as the highest but 0.28 for population 16 as the lowest. 3. The population 17 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown height) 158 though the branching angles were almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between population as shown In Fig. 3 and 4. 5. As to the serration density, number of stomata row and resin duct; the significant differences exist between individual trees within population and also between populations. 6. Population 18 shown resin duct index 0.119 as the maximum. 7. The patterns of diameter growth, based on the width of 10-year-ring segment unit(for example, the 1st segment denotes the with between pith center and 10th year ring and the 2nd one is from 11th to 20th ring and so on.), were alike among populations as shown in Fig 9. 8. Significant differences between population in mean summer wood percentage as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 14, 18 however vice versa in population 13, 15, and 17. 9. The fiber length was mereased with the increased of age but no differences between populations as shown in Fig. 12.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.323-330
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• 2010

This study was undertaken to compare early growth characteristics, such as height, diameter at root collar (DRC), and the dry weights of stem, branches, needles and roots between naturally regenerated and planted stands of Pinus densiflora for. erecta in Dae-gi and Bo-gwang site, Gangwon province, Republic of Korea. Average DRC growth was similar between the naturally regenerated and the planted stands in Dae-gi area, however, difference was statistically significant (P<0.01) between the naturally regenerated and the planted stands in Bo-gwang area, 4.66 cm and 2.61 cm, respectively. Average height of the naturally regenerated stands was significantly greater (P<0.01) than that of planted stands in both Dae-gi and Bo-gwang areas. The composition ratio of the dry weights for each part of measured trees was the highest in the stem in the naturally regenerated stands, but in the planted stands, the needle was the highest in both sites. The root/shoot ratio in the Dae-gi and Bo-gwang areas in the planted stands were much greater than those in the naturally regenerated stands, 0.25-0.30 and 0.17-0.18, respectively. The ratio of needle to stem biomass (N/S), branch to stem biomass (B/S), and needle to branch biomass (N/B) was significantly greater in the planted stands than those in the naturally regenerated stands in both sites. The results of this study represent that the regeneration methods, natural and artificial regenerations, can have an influence on the early growth of P densiflora for. erecta. This results not only provide the need for a correct planting method, but also will be useful in studies on the environmental adaptability of trees.