• Journal of Drive and Control
• /
• v.18 no.2
• /
• pp.38-45
• /
• 2021

In recent years, the demand for an onboard scale system which can directly monitor load distribution and overload of vehicles has increased. Depending on the suspension type of the vehicle, the onboard scale system could use different types of sensors, such as, angle sensors, pressure sensors, load cells, etc. In the case of a vehicle equipped with leaf spring suspension system, the load of the vehicle is measured by using the deflection or displacement of the leaf spring. Leaf springs have hysteresis characteristics that vary in displacement depending on the load state. These characteristics cause load measurement errors when moving or removing cargoes. Therefore, this study aimed at developing an onboard scale device for cargo vehicles equipped with leaf springs. A sectional modeling method which can reduce measurement errors caused by hysteresis characteristics was also proposed.

• Journal of Life Science
• /
• v.19 no.10
• /
• pp.1382-1388
• /
• 2009

Rubus crataegifolius is a shrub species and is primarily distributed throughout Asia and Europe. We collected 550 representative samples of the eleven populations in Korea to estimate leaf variation within species. The 35 morphological characteristics allowed us to resolve well-supported fixed characteristics and variable characteristics. Sixteen of twenty-three quantitative characteristics and five of twelve qualitative characteristics showed significant differences among populations. We argued that the population differentiation can accounted for the variation in phenetic characteristics such as spine in this species, but were less successful in accounting for variation in other traits. Within a polystatistic leaf structure, their morphological differences could be modulated by ecological pressure such as temperature, altitude, duration of sunshine, and solar radiation. The phenogram showed two distinct clades. One was a group in central Korea and the other was a group in the southern regions of Korea. If morphological characteristics in R. crataegifolius populations reflect their ecological niche, morphology should be regarded with caution as the main criterion for population studies in R. crataegifolius.

• Journal of People, Plants, and Environment
• /
• v.22 no.6
• /
• pp.551-561
• /
• 2019

This study was conducted to find out differences in the removal efficiency of particulate matter (PM) depending on the type of plants and the morphological characteristics of leaves. A total of 12 plants were used, with three plants selected for each type of leaves (big leaf, small leaf, compound leaf, needle leaf). We measured the removed amount of PM10 and PM2.5, the structure of the abaxial leaf surface, and the weight of the wax layer of each plant. Plants with the high removal efficiency of PM included Pachira aquatica Aubl., Ardisia crenata, and Dieffenbachia 'Marianne', and plants with the low removal efficiency included Nandina domestica Thunb, Schefflera arboricola, and Quercus dentata. The abaxial leaf surface having a high removal efficiency of PM had many large wrinkles, and the abaxial leaf surface having a medium removal efficiency was flat and smooth. On the other hand, there were many fine hairs on the abaxial leaf surface with a low removal efficiency. According to the plant leaf type, the PM10 removal efficiency of plants with needle leaves was about three times higher than that of other plants. In particular, the wax layer of conifers weighed 6-24 times higher than those of other plants. The stomata of conifers were evenly distributed on the adaxial and abaxial leaf surfaces; however, the stomata of Sciadopitys verticillata appeared in the form of papillae unlike general stomata. Therefore, the removal efficiency of PM varied depending on the macro-, and micro-morphological characteristics of plant leaves such as the structure of the abaxial leaf surface, and the weight of the wax layer. Based on this research, selecting plants that are effective in reducing PM in consideration of the plant type and leaf characteristics will improve indoor air quality and decrease exposure of PM to human body.

• Journal of the Korean Dietetic Association
• /
• v.20 no.2
• /
• pp.77-86
• /
• 2014

This study was carried out to evaluate the effects of stevia (Stevia rebaudiana Bertoni) leaf powder on soybean milk quality. Soybean milk was prepared with the addition of 0.1 g (SP1), 0.2 g (SP2), 0.3 g (SP3), 0.4 g (SP4) of stevia leaf powder. The pH of soybean milk added with stevia leaf powders ranged from 7.90 to 7.98, whereas that of control was 7.88. The viscosity of soybean milk added with stevia leaf powder was 11.13~12.71 cp while that of control was 11.09 cp. Soymilk added with stevia leaf powder yielded values of Hunter L (59.40~64.94), a (-7.63~-6.45), and b (18.71~19.63), whereas that of control were 67.45, -4.74 and 20.13, respectively. There was decrease upon addition of stevia leaf powder. During storage, the pH, viscosity, L, and b values were decreased continuously. According to sensory evaluation, taste, and flavor of SP3 were better than the other groups. Quality characteristics between control and SP3 showed no significant differences. Therefore, this study showed the possibility of substituting 0.3 g of stevia leaf powder instead of sugar for creating a standard quality soybean milk with low calories. Upon the results of this study, it may be assumed that there are consequences positive responses to health-oriented consumers when using stevia leaf powder.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.3
• /
• pp.216-223
• /
• 2003

This study was conducted to investigate the varietal differences in leaf senescence and the relationship between leaf senescence and photosynthesis during ripening stage of rice. During grain filling period, leaf senescence was evaluated by SPAD readings (an indirect indicator of chlorophyll content) for 3 rice varieties (SNU-SG1, Hwaseongbyeo, Nampungbyeo). SPAD value of flag leaf and 2nd leaf of SNU-SG1 were much higher than the other varieties and the leaves of SNU-SG1 also showed a tendency of delayed senescence as compared to the other varieties. Photosynthesis at light saturation (Pmax) of flag, 2nd and 3rd leaf in SNU-SG1 during grain filling period were much higher than Hwaseongbyeo and Nampungbyeo. The Pmax of the flag leaf in SNU-SG1 was especially higher over 20% than the other varieties. It was due to its higher mesophyll conductance and stomatal conductance as compared to the other varieties. Pmax, stomatal conductance and mesophyll conductance had positive correlation with SPAD value and nitrogen concentration of leaves. In conclusion, the stay green characteristics of SNU-SG1 would contribute to increasing the grain yield through the improved photosynthesis during grain filling.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.10
• /
• pp.147-153
• /
• 2004

This paper presents an analytical modeling technique fer representing a hysteretic behavior of a multi-leaf spring used for a large truck. It divides a nonlinear hysteretic curve of the multi-leaf spring into four parts; loading part, unloading part and two transition parts. It provides conditions fur branching to a part of the curve corresponding to a current multi-leaf spring status. This paper also presents a computational modeling technique of the multi-leaf spring. It models the multi-leaf spring with three links and a shackle. It assumes those components as rigid bodies. The links are connected by rotational joints, and have rotational springs at the joints. The spring constants of the rotational springs are computed with a force from the analytical model of the hysteretic curve of the multi-leaf spring. Static and dynamic tests are performed to verify the reliability of the presented techniques. The tests are performed with various amplitudes and excitation frequencies. The hysteretic curves from the tests are compared with those from the simulations. Since th e presented techniques reproduce the hysteretic characteristic of the multi -leaf spring faithfully, they contribute on improving the reliability of the computational model of a large truck.

• Journal of the Korean Society of Food Culture
• /
• v.33 no.3
• /
• pp.283-290
• /
• 2018

This study examined the quality characteristics and anti-oral microbial activity of bamboo leaf jelly prepared with different 5 levels (0, 10, 20, 30, and 40%) of bamboo (Phyllostachys nigra var. henonis) leaf extract. The sugar contents of bamboo leaf jelly were increased significantly by increasing the level of bamboo leaf extract. The luminance and Hunter's a values of the jelly samples increased with increasing bamboo leaf extract, but the 40% bamboo leaf jelly had the lowest Hunter's b values. The hardness, adhesiveness, gumminess, and chewiness increased significantly with increasing bamboo leaf extract. Among the mechanical properties, only the flavor of the jelly with 30 and 40% bamboo leaf extract were increased significantly. The extract of bamboo leaves had strong antimicrobial activity against S. mutans, S. sobriuns, P. gingivalis, and P. intermedia at a concentration of 40%. These results suggest that bamboo leaf extract can be useful in the production of high quality jelly.

• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.6
• /
• pp.576-581
• /
• 2004

This study was carried out to evaluate the sensory evaluation of the muffins with mulberry leaf powder as well as their chemical characteristics. The muffins were prepared by adding 0%, 1 %, 2% and 3% mulberry leaf powder to the recipe. As a result of the sensory evaluations, the color, flavor and texture of the muffins of 2% mulberry leaf powder were found to be much better than those of the other groups. In the chemical composition analysis, increasing the mulberry leaf powder led to a significant increase in the content of crude protein, moisture and crude ash, while crude fat was significantly decreased. As the ratio of mulberry leaf powder increased, Ca, Mg, Fe and Zn in the muffins increased proportionally (p<0.05). The lightness value, the redness value and the yellowness value decreased with the increase of mulberry leaves powder content. In a texture analyser test, hardness and cohesiveness decreased as the ratio of mulberry leaf powder increased. The adhesiveness of the muffins with 2% mulberry leaf powder was the strongest of all.

• Journal of the Korean Society of Food Culture
• /
• v.27 no.5
• /
• pp.521-527
• /
• 2012

This study was conducted to examine the quality characteristics of tofu prepared with Loquat (Eriobotrya japonica Lindl.) leaf powder (LLP). Moisture, crude ash, carbohydrate, crude protein, and crude lipid contents of Loquat leaf powder were 10.25, 6.72, 69.54, 8.23, and 5.26%, respectively. The yield rates, turbidity, and total acidity of tofu increased according to the quantity of added LLP, whereas pH level decreased. The L- and a-values of samples decreased as the amount of LLP increased, whereas b-value increased. With regard to textural characteristics, LLP addition increased hardness, chewiness, and brittleness, as well as reduced springiness and cohesiveness. In terms of overall acceptability, the most preferred tofu samples were the control and 0.3% LLP addition groups.

• Journal of the Korean Society of Tobacco Science
• /
• v.23 no.2
• /
• pp.149-155
• /
• 2001

This study was carried out to evaluate the correlations among degree of carbonization, chemical components and chromatic characteristics, and to establish the criterion of carbonizaion in leaf tobacco during aging storage. The flue-cured (B2O) and burley (B2T) leaf tobaccos were redried with conventional practices for each other type, and moisture contents of leaf tobaccos were adjusted to 13, 15, 17 and 19% after redrying. The leaf tobaccos were packed in carton box and stored for 8 months in the controlled-environment rooms($35^{\circ}C$, 65% R.H. and $40^{\circ}C$, 80% R.H.). Degree of carbonization, chemical components, and chromatic characteristics(L ; black-white, a ; red to green, b ; yellow to blue) were invetigated every month. Carbonization Index (C.I.) was established as (equation omitted) in accordance with degree of carbonization in two types. The C.I. value of flue-cured leaf(56.5) for slight carbonization was higher than that of burley leaf(48.0). C.I. and rate of usable leaf, L and b were positively correlated in two types. C.I. was significantly shown positive correlation with pH in two types. The correlations between the predicted and the observed values of slight carbonizating times(month after storage) using C.I. and pH were positive significant in two types. The results suggest that cabonization index may be useful to forecast and prevent the carbonization, and pH may be useful to estimate cabonization indirectly for flue-cured and burley leaves during aging storage.