• Journal of the Ergonomics Society of Korea
• /
• v.33 no.2
• /
• pp.143-153
• /
• 2014

Objective: The aim of this study is to investigate the effects of trunk-forearm supported sitting on trunk flexion angle, trunk extensor fatigue and seat contact pressure. Background: The relationship between sitting posture and musculoskeletal disorders of the trunk extensor fatigue and seat contact pressure has been documented. The trunk-forearm support type ergonomic chair was devised from the fact that trunk-forearm support has been reported to reduce trunk extensor activity and discomfort. Method: Using three different sitting postures, upright ($P_1$), trunk-forearm supported ($P_2$) and normal sitting ($P_3$), six healthy subjects participated in the study. Motion capture system was used to collect head and trunk flexion angle, and surface electromyography (sEMG) was used to collect myoelectric signal of upper trapezius, lower trapezius, erector spinae, multifidus, and pressure mat system was used to measure seat contact pressure. Results: When trunk and forearm were supported by the ergonomic chair, higher head flexion angle showed upright > trunk-forearm supported > normal in order, and muscle fatigue showed less than upright and normal sitting. Mean seat contact pressure decreased 19% than upright sitting. But muscle fatigue was not affected by each condition. Conclusion: Trunk-forearm supported sitting of the ergonomic chair showed positive effect in respect of trunk and head flexion angle, trunk extensor fatigue, seat contact pressure. To acquire comprehensive understanding of the effectiveness of the ergonomic chair, further studies such as anatomical effects from measurement of external applied loading effect to the body from interface pressure analysis are required. Application: The results of the publishing trend analysis might help physiological effects of trunk-forearm support type chair.

• Journal of Life Science
• /
• v.14 no.5
• /
• pp.840-846
• /
• 2004

A study for expression of Korean Mistletoe (KM) lectin gene (A,B) in Saccharomyces cerevisiae was done using transforming system of yeast. In order to overexpress the genes efficiently in yeast, two lectin genes (A,B) were re-cloned and modified including Kozak translation initiation sequence using PCR amplification. The constructed plasmids containing modified lectin A and B genes were transformed to S. cerevisea INVSc (MAT G, his3 $\Delta$1, leu2, trpl-289, ura3-52). The transformed cells were identified by DNA sequencing with ABI3700 system and induced with 2% of galactose for recombinant KM lectin (rKM lectin) protein. The rKM lectin A and B proteins were determinated about 29kDa size of protein by SOS-P AGE and western blotting analysis. The expressed recombinant lectin was determinated 1.24∼1.75 $\mu\textrm{g}$ per 1 mg of cytosolic soluble protein by sandwich ELISA method. Moreover the lectin genes were expressed as maximum level at 36 h after galactose induction and lectin A gene was were repressed after 48 h.

• Current Optics and Photonics
• /
• v.3 no.6
• /
• pp.555-565
• /
• 2019

Development of a biomarker for predicting tumor-treatment efficacy is a matter of great concern, to reduce time, medical expense, and effort in oncology therapy. In a preclinical study, we hypothesized that the blood-flow parameter based on laser speckle flowmetry (LSF) could be a potential indicator to estimate the efficacy of breast-cancer treatment. To verify this hypothesis, a 13762-MAT-B-III rat breast tumor was grown in a dorsal skinfold window chamber applied to a nude mouse, and the change in blood flow rate (BFR) - or the speckle flow index (SFI) is used together as the same meaning in this manuscript - was longitudinally monitored during tumor growth and metronomic cyclophosphamide treatment. Based on the daily LSF angiogram, several BFR parameters (baseline SFI, normalized SFI, and △rBFR) were compared to tumor size in the normal, treated, and untreated tumor groups. Despite the incomplete tumor treatment, we found that the daily changes in all BFR parameters tended to have partially positive correlation with tumor size. Moreover, we observed that the changes in baseline SFI and normalized SFI responded one day earlier than the tumor shrinkage during chemotherapy. However, daily variations in the hypercapnia-induced △rBFR lagged tumor shrinkage by one day. This study would contribute not only to evaluating tumor vascular response to treatment, but also to monitoring blood-flow-mediated diseases (in brain, skin, and retina) by using LSF in preclinical settings.

• Journal of Korea Foundry Society
• /
• v.29 no.5
• /
• pp.225-232
• /
• 2009

For comprehensive understanding of the formation behavior of $\beta-Al_5FeSi$ phase in Al-Si-Cu alloys with the existence of Fe element, microstructure characterizations were performed using combined analysis of OM, SEM-EDS, XRD. Especially, experimental and predictive works on solidification events of $\beta-Al_5FeSi$ phase as well as other phases formed together with $\beta-Al_5FeSi$ have been carried out by using DSC analysis and Java-based Materials Properties software (J. Mat. Pro.). Primary and eutectic $\beta-Al_5FeSi$ phases were able to distinguish from each other on microstructures by their morphological features. Primary $\beta-Al_5FeSi$ phase was seen to have rough surface perpendicular to growth direction, indicating free attachment of solute atoms in liquid state. On the other hand, the eutectic $\beta-Al_5FeSi$ phase was formed with plain and straight surface during eutectic reaction together with $\alpha$-Al phase. The eutectic reaction of $\beta-Al_5FeSi$ and $\alpha$-Al phases was seen to be able to separate into each formation depending on cooling rate.

• Journal of Korean Society of Disaster and Security
• /
• v.11 no.2
• /
• pp.61-67
• /
• 2018

Scour protection methods can be categorized as two types: The first is to reduce the horseshoe and wake vortices which are the main reasons for local scour. Either small cylindrical structures or separated vertical deflectors can be placed in front of the pier or the horizontal deflector (or collar) can be attached to the pier like the spoiler to reduce the dynamics of vortical structures. The second is to employ the protection layer to keep the bed material in place, which is a common method with a merit of immediate effect by using block mat or tetrapod. This study examined the effect of scour reduction using the former method. The relationship between the reflector interval and reduction of scour was not clear. It is assumed that the width of the reflector is somewhat correlated with the reduction of the scour. As the KC numbers increases, the Effect of Scour reduction rate is shown to decrease. Also, Scour reduction rate showed a rapid change at $U_R=25$ or KC = 8.

• Research in Plant Disease
• /
• v.27 no.2
• /
• pp.66-69
• /
• 2021

In 2020, a brown felt was observed on persimmon (Diospyros kaki) in persimmon orchards, Sangju, Korea. The symptom on persimmon was white to grey mycelial mats on some areas of the branches. Each mat progressively expanded until the mats coalesced to occupy larger areas and finally girdled the branches. The disease branches were covered with brown-colored mold, consisting of hyphal mats of the pathogen. Optimum temperature for mycelial growth was 30℃. On the basis of mycological characteristics, pathogenicity test, and molecular analysis with complete internal transcribed spacer rDNA region, the causal fungus was identified as Septobasidium sp. This is the first report of brown felt caused by Septobasidium sp. on persimmon in Korea.

• Geomechanics and Engineering
• /
• v.28 no.4
• /
• pp.385-396
• /
• 2022

The accurate determination of the subgrade reaction modulus (K_s) of soil is an important factor for geotechnical engineers. This study estimated the K_s of soft soil improved with floating deep cement mixing (DCM) columns. A novel prediction model was developed that emphasizes the accuracy of identifying the most significant parameters of K_s. Several multi-layer perceptron (MLP) models that were trained using the Levenberg Marquardt (LM) backpropagation method were developed to estimate K_s. The models were trained using a reliable database containing the results of 36 physical modelling tests. The input parameters were the undrained shear strength of the DCM columns, undrained shear strength of soft soil, area improvement ratio and length-to-diameter ratio of the DCM columns. Grey wolf optimization (GWO) was coupled with the MLPs to improve the performance indices of the MLPs. Sensitivity tests were carried out to determine the importance of the input parameters for prediction of K_s. The results showed that both the MLP-LM and MLP-GWO methods showed high ability to predict K_s. However, it was shown that MLP-GWO (R = 0.9917, MSE = 0.28 (MN/m²/m)) performed better than MLP-LM (R =0.9126, MSE =6.1916 (MN/m²/m)). This proves the greater reliability of the proposed hybrid model of MLP-GWO in approximating the subgrade reaction modulus of soft soil improved with floating DCM columns. The results revealed that the undrained shear strength of the soil was the most effective factor for estimation of K_s.

• Journal of Korean Theatre Studies Association
• /
• no.53
• /
• pp.203-233
• /
• 2014

Depuis les $ann{\acute{e}}es$ 1990, sous l'influence de la $pens{\acute{e}}e$ postmoderne, des ${\oe}uvres$ $d{\acute{e}}constructivistes$ ont fait leur apparition dans le $th{\acute{e}}{\hat{a}}tre$ $cor{\acute{e}}en$. Cependant, cette approche est plus remarquable dans le domaine du $th{\acute{e}}{\hat{a}}tre$ pratique que dans celui de $l^{\prime}{\acute{e}}criture$ dramatique. Par exemple, ce mouvement a $commenc{\acute{e}}$ avec les metteurs en $sc{\grave{e}}ne$ OH Tae-suk et GUI Gook-seo au $d{\acute{e}}but$ des $ann{\acute{e}}es$ 1990. Leur ont $succ{\acute{e}}d{\acute{e}}$ ensuite les metteurs en $sc{\grave{e}}ne$ CHOI Yong-hoon, de la troupe de $th{\acute{e}}{\hat{a}}tre$ Chak Eun Shin Hwa, et PARK Kun-hyung. De plus, actuellement, de jeunes metteurs en $sc{\grave{e}}ne$ travaillent avec $perspicacit{\acute{e}}$, tels que KO Sung-woong, KANG Lyang-won et YOUN Han-sol. A $l^{\prime}oppos{\acute{e}}$ de ce $th{\acute{e}}{\hat{a}}tre$ pratique, $l^{\prime}{\acute{e}}criture$ dramatique des $pi{\grave{e}}ces$ de $th{\acute{e}}{\hat{a}}tre$ demeure au niveau de $l^{\prime}{\acute{e}}criture$ $repr{\acute{e}}sentative$ et est encore sans grande valeur. Pour $r{\acute{e}}fl{\acute{e}}chir$ ${\grave{a}}$ ce $probl{\grave{e}}me$, nous $consid{\acute{e}}rerons$ les $pi{\grave{e}}ces$ de Michel Vinaver dont la dramaturgie oppose $l^{\prime}{\acute{e}}criture$ $d{\acute{e}}constructiviste$ au principe $repr{\acute{e}}sentatif$ et ${\grave{a}}$ $l^{\prime}{\acute{e}}criture$ traditionnelle en ${\acute{e}}chappant$ au principe de $causalit{\acute{e}}$. Avec sa $strat{\acute{e}}gie$ de montage $sp{\acute{e}}cifique$, il $proc{\grave{e}}de$ avec une ${\acute{e}}criture$ $fragment{\acute{e}}e$ tout en $ins{\acute{e}}rant$ des dialogues $h{\acute{e}}t{\acute{e}}rog{\grave{e}}nes$. Il trouve ainsi le silence des mots, un $pr{\acute{e}}sent$ sensible, la $mat{\acute{e}}rialit{\acute{e}}$ des mots et des images ostensives ${\grave{a}}$ travers des dialogues $juxtapos{\acute{e}}s$, une $simultan{\acute{e}}it{\acute{e}}$ et une $discontinuit{\acute{e}}$ du dialogue. En examinant ses $pi{\grave{e}}ces$ de $th{\acute{e}}{\hat{a}}tre$, nous explorons cette nouvelle ${\acute{e}}criture$ qui $r{\acute{e}}siste$ au $r{\acute{e}}gime$ dramatique de la $repr{\acute{e}}sentation$. Toutefois, nous n'encenserons pas seulement cette ${\acute{e}}criture$ postmoderne. Plus $pr{\acute{e}}cis{\acute{e}}ment$, nous $rel{\grave{e}}verons$ ses limites, dans les circonstances $pr{\acute{e}}sentes$, en $r{\acute{e}}fl{\acute{e}}chissant$ aux limites du $th{\acute{e}}{\hat{a}}tre$ postmoderne depuis le $d{\acute{e}}but$ des $ann{\acute{e}}es$ 2000. Ce faisant, nous souhaitons $d{\acute{e}}finir$ de nouvelles $possibilit{\acute{e}}s$ $esth{\acute{e}}tiques$.

• Korean journal of applied entomology
• /
• v.4
• /
• pp.19-24
• /
• 1965

In an attempt to find a satisfactory environmental factors which facilitate abundant conidial production of Piriculariaoryzae Cav. on tomato juice media, various environmental factors were studied for their effect on sporulation and mycelial growth of the fungus. Those factors were conditions of irradiation, color of light, age of culture and pH of the media. l) Continuous exposure to fluorescent light (Mitsubish FL-20-35 W) produced more conidia and much mycelial growth than did intermittent photoperiods and darkness. 2) Of 3 cellophane filters and direct exposure to fluorescent light used, conidia were produced best under the direct exposure to the light. Conidial production in color filter conditions sequently decreased with red, yellow and blue. Growth of mycelium was not significantly different within colors. 3) Periodic irradiation of 12-hour unit brought about zones on mycelial growth no matter what the color filter was used. 4) Older cultures responding to the light were more stimulated by light than were the younger one in the conidia production, but maximum production of conidia was 48 hours of age in this case. 5) Color of the mycelial mat and the aerial mycelium seemed to have a close relation to the production of conidia. The more darkness of the mycelial mat was produced the more conidia and the much aerial mycelium was produced the least conidia. The color of mycelium was more dark under the continuous irradiation than continuous darkness, while the periodic irradiation showed intermediate effect. 6) The concentration of hydrogen ion for growth and sporulation of the fungus was investigated the ranges between 5 and 9. The best pH for the fungus was also noted at 7. whereas the below of pH 4 was not occurred any mycelial growth and sporulation.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.65 no.1
• /
• pp.63-71
• /
• 2020

The purpose of this study was to analyze the growth characteristics of perilla according to the materials of the seedbed for the development of seedling plug technology suitable for the mechanical transplantation of perilla. Perilla (Perilla frutescens var. japonica Hara) cultivars Deulsaem and Sodam were used in this experiment. The composition ratios of 170 products from 16 companies published in the 'Korean Association of Seedbed Media' homepage were compared according to usage and type, and 11 products that corresponded to the average were selected. The seedbed was classified according to the seedbed for paddy rice as light-weight, semi-weight, and weight, and based on the seedbed for horticulture, as light-weight and ultra-light. The seedlings were placed in 72-cell (semi-automatic), 128-cell (automatic) and 220-cell (automatic) plug trays. We selected 2 light-weight seedbeds of paddy rice and 2 light-weight seedbeds of horticultural products with the highest plant growth. We analyzed plant height and mat formation of the perilla roots. Results showed that the perilla height and mat formation were the best in light-weight seedbeds of paddy rice (product R1). Therefore, light-weight seedbeds of rice (product R1) were suitable for perilla plant transplantation. The estimated major components were vermiculite 41.0%, cocopeat 31.0%, peat moss 5.7%, and red-yellow soil 20.0%. The mechanical transplantation of perilla significantly boosts plant growth and reduces sowing and thinning efforts. However, continuous evaluation of newly introduced, commercial seedbeds is needed.