• Computers and Concrete
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• v.11 no.4
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• pp.271-289
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• 2013

In this research, a developed microstructural model of cement particles was presented to describe the cement hydration procedure. To simplify the hydration process, the whole hydration was analyzed in a series of sub-steps. In each step, the hydration degree, as well as the microstructural size of the hydration cell, was calculated as a function of the radius of the unreacted cement particles. With the consideration of the water consumption and the reduction of the interfacial area between water and hydration products, the micro-level expressions of the cement hydration kinetics were established. Then the heat released and temperature history of the concrete was carried out with the hydration degree obtained from each sub-steps. The equivalent age method based on the Arrhenius law was introduced in this research. Based on the equivalent age method, a maturity model was applied to describe the evolution of the mechanical properties of the material during the hydration process. The finite element program ANSYS was used to analyze the temperature field in concrete structures. Then thermal stress field was calculated using the elasticity modulus obtained from code formulate. And the risk of thermal cracking was estimated by the comparison of thermal stress and concrete tensile strength.

• The Journal of Korean Physical Therapy
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• v.16 no.1
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• pp.60-69
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• 2004

Many methods have been described for the early intervention of adolescent idiopathic scoliosis. Adolescent idiopathic scoliosis is lateral and rotational spinal curvature in absence of associated congenital or neurologic abnormalities, the most common type of scoliosis observed in child and young adults, and refers to curves that develop after the age of $10{\sim}18$. The curves of adolescent idiopathic scoliosis have the potential to progress rapidly during growth. Curves are currently universally measured by the Cobb's method and Ferguson method. Some curves do not remain small, these may be mildly or severely progressive and the ribs on the convex side of the curve separate, and those on the concave side ribs approximate so rib undergoes deformation with rib humping. The latter may make angles that can affect vestibular system, balance, sensory, especially cardipulmonary function. Intervention for adolescent idiopathic scoliosis is based on the patient's age, the angular value of the curve, the maturity of their skeleton, and the topography. The purpose of intervention for adolescent idiopathic scoliosis consists of knowing how to go to the best approach the correction of the lateral curve and rotational deformity holding the achieved for the remainder of spinal growth, preventing significant cosmetic abnormality, pain and cardiopulmonary complication, control the muscle imbalance and proprioceptive postural disturbances, be less need for radical surgery to avoid early surgery.

• KIEAE Journal
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• v.12 no.4
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• pp.59-69
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• 2012

In order to create humanitarian living environment with sustainable ecological environment, urban regeneration project has been implemented recently seeking diverse methods for residents'participation stressing the process of communication with the residents changing from the existing one way planning by limited number of experts. Particularly, it is essential to develop systematic tools to promote the voluntary and positive participation of the residents because residents have to perform as the master of urban streetscape design project that requires sophisticated knowledge and experience and also because the residents have to function as sustainable maintainers and managers of their streetscape. This study intends to identify the organizational structure and major contents of design guideline as a tool to support the voluntary and positive participation of the residents in streetscape maintenance. For this purpose based on the structural system and characteristics of Chicago streetscape design guideline that was developed as tool for residents' participation, efforts were made to set up framework of design guideline for sustainable streetscape project with the users' participation with their overall understanding and trust. In detail, the author studied the resident participatory process for sustainable maintenance and management in a long term landscape project and the principle and theories of design planning for streetscape that supports the utilizing behaviors of the users, and how this information should be linked and organized to form the structure and contents of design guideline. As a tool supporting residents' participation and helping the residents perform the responsible function as sustainable maintainers and managers of their streetscape through social maturity with ontological sense of masters of their local community as they experience the gradual processes of their streetscape maintenance project, streetscape design guideline has its meaning in the efforts that tried to achieve deep participation of the residents through researches converging the two academic sectors of urban architecture and social psychology.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.4
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• pp.251-258
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• 2021

Dental trauma is very common in children and relatively young people, with the line of treatment depending on the time elapsed, age of the child, and tooth maturity. If the fractured segment is available and there is close approximation of the segment to the remaining tooth, reattachment of the fractured segment is a feasible option. This treatment offers several advantages, including the reestablishment of function, aesthetics, shape, shine and surface texture, in addition to the original contour and alignment of the teeth. The following cases present two different complex crown fracture cases that were treated using tooth fragment reattachment with fiber-reinforced composite post.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.2
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• pp.91-100
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• 2002

The field experiments were carried out to examine for the mesh selectivity in trammel net and optimum mesh size, during Aug. 10~13, Non 9~13 2000 in Jumunjin, Kangwon-Do and during Jun. 1~27 2001 in Suyong-Bay, Busan. The experiments in Jumunjin area were conducted by using trammel nets with seven different mesh sizes (60, 75, 90, 105, 135, 150, 180mm) and those in Suyong-Bay were done by using trammel nets and gill nets with three different mesh sizes (60, 75, 90mm) in order to compare two types of nets of same structure. The mesh selectivity analysis was done mainly with flat fish(Eopsetta grigorjewi) that was occupied 60% out of total catches. And the mesh selectivity was written by extension of Kitahara's method included master curve with function type. The results obtained are summarized as follows 1. Total number of catch by, trammel net was 2,331 and that of gill net was 1,433, and flat fishes occupied 59.8 ~60% in total catches. 2. The value of optimum l/m by, trammel net was higher about 0.1 than that of gill net according as trammel net was 2.56, and gill net was 2.47. 3. The 50% selection range by, trammel net was wider about 1.5 time than that of gill net according as trammel net was 1.88~3.36(1.48) and gill net was 2.00~3.02(1.02). 4. The optimum mesh size(OMS) was estimated that trammel net was about 141mm and gill net was about 132mm on first maturity length(FML) 265mm of flat fish. 5. On the optimum mesh size based on the first maturity length of flat fish, The 50% range by, trammel net was wider about 76mm than that of gill net according as trammel net was 265 mm~474mm and gill net was 265mm~398mm.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.298-306
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• 2016

Planting date shift is one of the means of adapting to climate change in Kimchi Cabbage growers in major production areas in Korea. This study suggests a method to estimate the potential yield of Kimchi Cabbage based on daily temperature accumulation during the growth period from planting to maturity which is determined by a plant phenology model tuned to Kimchi Cabbage. The phenology model converts any changes in the thermal condition caused by the planting date shift into the heat unit accumulation during the growth period, which can be calculated from daily temperatures. The physiological maturity is estimated by applying this model to a variable development rate function depending either on growth or heading stage. The cabbage yield prediction model (Ahn et al., 2014) calculates the potential yield of summer cabbage by accumulating daily heat units for the growth period. We combined these two models and applied to the 1km resolution climate scenario (2000-2100) based on RCP8.5 for South Korea. Potential yields in the current normal year (2001-2010) and the future normal year (2011-2040, 2041-2070, and 2071-2100) were estimated for each grid cell with the planting dates of July 1, August 1, September 1, and October 1. Based on the results, we divided the whole South Korea into 810 watersheds, and devised a three - dimensional evaluation chart of the time - space - yield that enables the user to easily find the optimal planting date for a given watershed. This method is expected to be useful not only for exploring future new cultivation sites but also for developing cropping systems capable of adaptation to climate change without changing varieties in existing production areas.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.979-986
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• 2005

Lead (Pb) exposure during development can produce neurological deficits. In this study, the effect of Pb exposure during neonatal development via lactation on anxiety of brain function was investigated. Long-Evans strain rats were raised through two generations. At the birth of the second generation, the dams were subdivided into two groups and supplied drinking water containing either $0.2\%$ Pb (Pb-treated group) or sodium (Na, Control group) acetate until weaning. Rats were sacrificed at 3 (weaning) and 11 weeks (maturity) for brain Pb and fatty acid analysis. Motor activity and elevated plus maze tests were initiated at 9 weeks. The brains in the Pb-treated group at weaning and maturity contained 1486$\pm$98 and $270{\pm}46$ ng Pb/g, respectively The control group showed the background level of Pb ($3.7{\pm}1.0_{ng}$ Pb/g) in both ages. The alterations in brain fatty acid composition induced by Pb exposure were more evident in 3 wks old than 11 wks old. For example, in 3 wks old, the percentages of $18:2_{n-6}$, $20:2_{n-6}$ and $18:2_{n-6}$ were decreased in the Pb-treated group with an increase in $20:4_{n-6}$ In motor activity test, there was a tendency of hyperactivity in the Pb-treated group compared with the control group but the difference was not significant. In elevated plus maze test, the Pb-treated group showed fewer numbers of visits to the open arms (P < 0.05), indicating that Pb exposure may lead to anxiogenic effect.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.419-425
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• 2011

Changes in the flavor of muskmelons stored at different temperatures were examined to judge aroma patterns during storage. A mass-spectrometry based electric nose was used to distinguish the subtle differences in the muskmelon's volatile compounds. The data were used for a discriminant function analysis (DFA), and then the partial least square algorithm was used for a quantitative analysis. Volatile components in the muskmelons increased with storage, and the first discriminant function score (DF1: $r^2$=99.88%, F=3072.5) moved from a positive position to a negative position as the storage period increased. The proper point of maturity was anticipated as the $28^{th}$ day at 0$^{\circ}C$, $21^{st}C$ day at 4 and 7$^{\circ}C$, and $14^{th}$ day at 10$^{\circ}C$. Also, using the DF1 score we could predict the general tendency (vitamin C, stem moisture, acidity) of the muskmelons. The electronic nose revealed that the major volatile compounds that changed during storage of the melons were ethyl ethyl acetate, butyl acetate, nonanol, dodecanoic acid, hexadecanoic acid and tricosane. The amount of volatile compounds detected increased during storage.

• Applied Microscopy
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• v.35 no.2
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• pp.97-104
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• 2005

Plant epidermis consists of relatively unspecialized cells and more specialized cells of various structure and function. Trichomes are specialized cells originated from the epidermis and much attention has been paid to the plants developing trichomes with peculiar structure and function. The present study has been undertaken to examine the trichome type noticed in the leaf epidermis of Althaea rosea using scanning electron microscopy. Four types, namely simple, short-and long-tufted, and glandular hairs, were detected in their epidermis. Their Distribution, frequency and structure varied by the development and epidermal surface. The most frequently distinguished type was the tufted ones growing in young leaves of the abaxial epidermis, while the simple hairs were rare throught the examination. The short-tufted hairs branched up to seven times having each branchlet about $160{\sim}210{\mu}m$ in length at maturity. The long-tufted hairs exhibited up to ten branchlets, where branchlets could reach up to $900{\sim}1,000{\mu}m$ long when fully expanded. Glandular trichome was the peltate type comprising $1{\sim}2$ secretory head cells, 2 stalk cells and a basal cell. The short peltate glandular hairs, usually not exceeding $40{\mu}m$, differentiated more along the areoles in the adaxial epidermis. The function of these trichomes in A. rosea has been still obscure, but it has been speculated that they probably play a role in protection; non-glandular ones possibly providing a defense against insects and secretory glandular type participating in chemical defense. Structural features of these trichomes at cellular level will be discussed in the following study of transmission electron microscopy.

• Korean Journal of Poultry Science
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• v.49 no.4
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• pp.229-237
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• 2022

This study investigated the growth characteristics of four strains of newly developed synthetic Korean native commercial chickens (KNCs). We investigated a suitable growth curve model in KNCs and estimated the number of days to reach a 2 kg market weight. Body weight was measured at 2-week intervals from birth to 12 weeks of age. The growth curves were estimated using von Berteralanffy, Gompertz, and logistic functions. The results showed that males were significantly heavier than females at all ages, but there were no significant differences in body weight between strains, except at birth and 2 and 6 weeks of age. The coefficients of determination and adjusted determination of growth function had high goodness-of-fit (97.4~99.7). Of the growth curve parameters, the mature weight and growth ratio were higher in males than in females, but the maturity rate was similar in males and females. The inflection point occurred at approximately 7 weeks of age for females and 8 to 9 weeks of age for males. The weights estimated from the growth curve functions almost agreed with the actual weights, except for male weights estimated using the von Bertalanffy function. The coefficients of determination of the regression equations for weight to age were 0.9583 to 0.9746. The 8- and 10-week-old body weights estimated using the regression equation, and the 12-week-old weight estimated using the logistic function were most similar to the actual weight. Using these models, the estimated age of KNCs to reach 2 kg was 62.0~64.6 days for males and 74.9~78.6 days for females.