• 한국축산시설환경학회지
• /
• 제20권3호
• /
• pp.117-124
• /
• 2014

The objectives were to assess the use of near-infrared reflectance spectroscopy (NIRS) as a tool for estimating nutrient compositions of corn kernel, and to apply an NIRS-based indium gallium arsenide array detector to the system for collecting spectra and analyzing calibration equations using equipments designed for field application. Partial Least Squares Regression (PLSR) was employed to develop calibration equations based on representative data sets. The kennard-stone algorithm was applied to induce a calibration set and a validation set. As a result, the method for structuring a calibration set significantly affected prediction accuracy. The prediction of chemical composition of corn kernel resulted in the following (kennard-stone algorithm: relative) moisture ($R^2=0.82$, RMSEP=0.183), crude protein ($R^2=0.80$, RMSEP=0.142), crude fat ($R^2=0.84$, RMSEP=0.098), crude fiber ($R^2=0.74$, RMSEP=0.098), and crude ash ($R^2=0.81$, RMSEP=0.048). Result of this experiment showed the potential of NIRS to predict the chemical composition of corn kernel.

• Journal of the Korean Wood Science and Technology
• /
• 제47권5호
• /
• pp.655-662
• /
• 2019

This study evaluated the multi-bonding performances of timbers as well as those of reinforcement and timber to obtain data for preparing guidelines regarding the use of timbers as large structural members. For the multi-bonding performances of timbers, four types of bonding surfaces were prepared according to the pith position. For the bonding performances of FRP (fiber-reinforced plastic)/steel plate and timber, a total of 11 types of specimens were produced for the selection of the appropriate adhesive. The bonding performances of the produced specimens were evaluated through a water soaking delamination test, a water boiling delamination test, and a block shear strength test. The test results showed that the bonding strength of the bonding surface according to the pith position was highest in the specimen for which the two sections with the pith at the center of the cross-section on timber and between the bonding surfaces (the tangential and radial sections were mixed) were bonded. Furthermore, the specimens for which the section (radial section) with the pith on the bonding surface of the timber was bonded showed a high delamination percentage. The results of the block shear strength test showed that the bonding section did not have a significant effect on the shear strength, and that the measured wood failure percentage was higher than the KS standard value. The PVAc adhesive showed the highest bonding strength between larix timber and GFRP (glass FRP). Furthermore, the epoxy and polyurethane adhesives showed good bonding strength for CFRP (carbon FRP) and structure steel, respectively.

• Smart Structures and Systems
• /
• 제26권6호
• /
• pp.681-692
• /
• 2020

Conventional Piezoelectric Energy Harvesters (CPEH) have been extensively studied for maximizing their electrical output through material selection, geometric and structural optimization, and adoption of efficient interface circuits. In this paper, the performance of Stepped Piezoelectric Energy Harvester (SPEH) under harmonic base excitation is studied analytically, numerically and experimentally. The motivation is to compare the energy harvesting performance of CPEH and SPEHs with the same characteristics (resonant frequency). The results of this study challenge the notion of achieving higher voltage and power output through incorporation of geometric discontinuities such as step sections in the harvester beams. A CPEH consists of substrate material with a patch of piezoelectric material bonded over it and a tip mass at the free end to tune the resonant frequency. A SPEH is designed by introducing a step section near the root of substrate beam to induce higher dynamic strain for maximizing the electrical output. The incorporation of step section reduces the stiffness and consequently, a lower tip mass is used with SPEH to match the resonant frequency to that of CPEH. Moreover, the electromechanical coupling coefficient, forcing function and damping are significantly influenced because of the inclusion of step section, which consequently affects harvester's output. Three different configurations of SPEHs characterized by the same resonant frequency as that of CPEH are designed and analyzed using linear electromechanical model and their performances are compared. The variation of strain on the harvester beams is obtained using finite element analysis. The prototypes of CPEH and SPEHs are fabricated and experimentally tested. It is shown that the power output from SPEHs is lower than the CPEH. When the prototypes with resonant frequencies in the range of 56-56.5 Hz are tested at 1 m/s2, three SPEHs generate power output of 482 μW, 424 μW and 228 μW when compared with 674 μW from CPEH. It is concluded that the advantage of increasing dynamic strain using step section is negated by increase in damping and decrease in forcing function. However, SPEHs show slightly better performance in terms of specific power and thus making them suitable for practical scenarios where the ratio of power to system mass is critical.

• Steel and Composite Structures
• /
• 제43권4호
• /
• pp.447-456
• /
• 2022

Recent experimental studies showed that deep steel I-shaped profiles classified as high ductility class sections in seismic design international codes exhibit low deformation capacity when subjected to cyclic loading. This paper presents an innovative retrofit solution to increase the rotation capacity of beams using bonded carbon fiber reinforced polymers (CFRP) patches validated with advanced finite element analysis. This investigation focuses on the flexural cyclic behaviour of I-shaped hot rolled steel deep section used as beams in moment-resisting frames (MRF) retrofitted with CFRP patches on the web. The main goal of this CFRP reinforcement is to increase the rotation capacity of the member without increasing the overstrength in order to avoid compromising the strong column-weak beam condition in MRF. A finite element model that simulates the cyclic plasticity behavior of the steel and the damage in the adhesive layer is developed. The damage is modelled using the cohesive zone modelling (CZM) technique that is able to capture the crack initiation and propagation. Details on the modelling techniques including the mesh sensitivity near the fracture zone are presented. The effectiveness of the retrofit solution depends strongly on the selection of the appropriate adhesive. Different adhesive types are investigated where the CZM parameters are calibrated from high fidelity fracture mechanics tests that are thoroughly validated in the literature. This includes a rigid adhesive commonly found in the construction industry and two tough adhesives used in the automotive industry. The results revealed that the CFRP patch can increase the rotation capacity of a steel member considerably when using tough adhesives.

• 한국의류산업학회지
• /
• 제24권6호
• /
• pp.801-811
• /
• 2022

In this study, we constructed a database of dyeing concentrations of all reactive dyes used for dyeing linen according to the thickness of the linen fabric and attempted to improve the reproducibility of the dyeing process for the commercialization of linen fabric materials. Linen fabric is a natural cellulose material that is comfortable and suitable for eco-friendly trends. It is a typical summer material with excellent breathability and thermal conductivity, quick moisture absorption and dissipation, and a cool touch. Dyeability and fastness were evaluated depending on the thickness of the linen fabric using a monochlorotriazine (MCT) reactive dye and bifunctional yellow, red, and blue dyes. All three colors of the MCT reactive dye and bifunctional dyes exhibited a darker shade as the fiber thickness of the marker increased. Fastness to washing was excellent at grades 4-5 or higher, regardless of the color of the dye and the number of linen fabrics. Although some color-fastness differences were noted, with the color change occurring most frequently with blue color, the fastness variations with dye type were mostly similar. The results of this study are expected to facilitate the selection of reactive dyes according to the thickness of the linen fabric based on the basic data from the laboratory, which will aid in the mass production of linen fabric and benefit the fashion industry.

• 한국식생활문화학회지
• /
• 제22권3호
• /
• pp.323-329
• /
• 2007

The objective of this study was to compare the healthy dining out attitude of restaurant diners by self-rated health status. Using healthy dining attitude and behavior questionnaire and a single question describing self-rated health status, the needs and importance of healthy dining out was detected. Mean age of the 182 respondents was 38.9${\pm}$11.37 years old and 37.4% of the respondents answered their mean monthly income was over 6,000,000won showing the subjects belonged in high income diners. The needs of healthy dining measured by five scales and offering healthy menus(3.80), labeling foods about original country(3.79), using environmentally friendly foodstuffs(3.71) and labeling nutrients on menu board(3.62) show higher score than others. A total of 76.4% of the respondents assessed their health status as 'good-rated Health' and 23.6% was 'poor-rated health'. There was no difference in frequency of eating out by self-perception of health status but, the 'poor-rated health' group need more nutrition information in restaurant specially for calorie(p<0.05), cholesterol(p<0.05), fiber(p<0.05), functional nutrients(p<0.001) showing significant differences comparing to 'good-rated health' group. In good-rated health group, selection of Korean cuisine for eating out was more frequent than the poor. The results shows the needs of healthy dining can be varied by diner's health status and therefore restaurateur should focus on understanding of the needs of diners with various health status.

• 한국작물학회지
• /
• 제68권3호
• /
• pp.175-187
• /
• 2023

Peanuts, also known as groundnuts (Arachis hypogaea L.), are globally recognized as a vital oilseed crop. Peanuts are rich in proteins (e.g., arginine), oils (e.g., oleic acid and linoleic acid), fiber, vitamins (e.g., niacin and tocopherol), and carbohydrates and are consumed worldwide. However, the presence of aflatoxin (AF) has garnered substantial attention since its initial discovery as the causative agent of Tukey's X disease in the United Kingdom in 1960. Among the 18 aflatoxins identified, aflatoxin B₁ (AFB₁) has the highest toxic activity and causes hepatocellular carcinoma. It is classified as Group I by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO). The present study was conducted to evaluate aflatoxin B₁ resistance of 102 peanut accessions and select putative aflatoxin B₁-resistant peanut accessions to aflatoxin B₁. One hundred and one Korean germplasms harvested in 2020 were inoculated with A. flavus to identify aflatoxin-resistant cultivars, and the aflatoxin B₁ concentration was measured using an ultra-performance liquid chromatography-photodiode array detector. Twenty-six accessions with aflatoxin B₁ concentrations lower than those of the check plant 55-437 were chosen for the development of aflatoxin-resistant varieties in Korea. As Korean aflatoxin-resistant varieties have not yet been developed, the findings of the present study are expected to provide useful information for the development of aflatoxin-resistant cultivars.

• 한국초지조사료학회지
• /
• 제42권1호
• /
• pp.26-31
• /
• 2022

본 연구는 여름 사료작물 재배기간에 빈번하게 발생하는 가뭄, 폭우 등 이상 기후에 대응한 여름철 응급 조사료 자원을 선발하고 잠재적 생산성을 평가하기 위해 2020년 5월부터 2021년 10월까지 충청남도 천안시 소재 국립축산과학원 축산자원개발부 초지 조사료 시험포장에서 재배시험을 수행하였다. 시험 초종은 여름철 응급조사료 자원으로 유망한 사료용 피(Echinochloa species cv. Shirohie and Jeju native), 재래기장(Panicum miliaceum cv. Native), 진주조(Pennisetum glaucum cv. Feed milk 2), 클라인그라스(Panicum coloratum cv. Selection 75), 테프그라스(Eragrostis tef cv. Tiffany)를 수집하여 파종은 2020년에 5월 21일과 6월 23일에 각 각 파종하였으며 2021년에는 5월 21일과 6월 21일에 2회 파종하였다. 사료용 피와 클라인그라스의 출현소요일은 6~10일 정도로 파종 후 가장 늦게 출현되었고 재래기장과 진주조는 5~6일 소요되었으며 테프그라스는 3일로 가장 빨리 출현되었다. 파종부터 수확까지 재배기간은 사료용 피 만생종(84일 이내)을 제외하고 모든 초종이 60일 이내에 출수기에 도달하였다. 파종시기별 건물수량은 5월 파종에서 사료용 피 만생종의 건물수량이 23,872 kg/ha로 가장 높게 나타났으며 클라인그라스가 3,888 kg/ha로 가장 낮게 나타났다. 6월 파종은 사료용 피 만생종의 건물 수량이 17,032 kg/ha로 가장 높게 나타났으며 재래기장, 테프그라스와 클라인그라스가 각각 5,468, 5,442 및 5,197 kg/ha로 가장 낮게 나타났다. 조단백질 함량은 초종별로 다양하게 나타났는데 사료용 피 조생종, 테프그라스, 클라인그라스가 높은 경향을 보였으며 사료용 피 만생종이 5.7~5.9%로 가장 낮게 나타났다. 중성세제불용성섬유소(NDF)와 산성세제불용성섬유소(ADF) 함량은 5월 파종은 초종 간에 큰 차이를 보이지 않았으나 6월 파종은 클라인그라스가 나머지 초종에 비해 낮게 나타났다.

• 한국식품과학회지
• /
• 제48권3호
• /
• pp.256-261
• /
• 2016

보릿가루의 활용도를 높이기 위하여 5가지 품종의 보리에 대한 도정도별 기능성분 변화를 분석하였다. 도정도별 총 폴리페놀 함량은 도정도가 27, 23, 19, 15%와 원곡으로 감소함에 따라 각각 0.97-1.40, 1.19-1.66, 1.22-1.77, 1.30-1.93과 1.46-2.12 mg/g 범위에서 증가하였으며, 총 플라보노이드 함량 또한 도정도가 감소함에 따라 증가하였으며, 유색보리인 흑누리와 보석찰이 높았다. 식품섬유 함량은 도정도가 감소함에 따라 각각 10.79-13.36, 10.78-14.34, 10.34-14.71과 10.47-14.87 g/100 g (원곡 18.21-21.22 g/100 g) 범위에서 증가하였으며, 베타글루칸 함량은 감소하였다. 찰성보리인 흰찰쌀과 보석찰이 식품섬유와 베타글루칸 함량이 높았다. 총 아라비노자일란 함량은 도정도가 감소함에 따라 증가하였다. GABA 함량은 도정도에 따라 각각 0.33-1.79, 0.33-1.84, 0.48-2.02와 0.55-2.26 mg/100 g (원곡 1.61-4.46 mg/100 g) 범위에서 증가하였으며, 품종에 따라 큰 차이를 나타내었다. 이상의 결과로 부터 보리를 이용한 가공제품을 개발하기 위해서는 가공적성을 파악하여 적합한 품종과 도정도를 결정하기 위한 연구가 진행되어야 할 것으로 판단된다.

• 농업과학연구
• /
• 제43권5호
• /
• pp.802-809
• /
• 2016

The objective of this study was to evaluate the nutritional value of commercial compound feeds for late finishing Hanwoo steers using detailed chemical analysis and an in vitro rumen fermentation trial. A total of 4 different feeds were selected and used to conduct a chemical analysis for their nutrient contents. The largest variation in nutrients contents among experimental feeds was found in ether extract and the smallest one was found in total digestible nutrients. Commercial feeds C and D had a higher energy value than the others. Even if C and D had a similar feed energy value, the components used to increase energy differed between them (non-fiber carbohydrate [NFC] for C; ether extract for D). In the in vitro trial, no significant difference was observed in dry matter in vitro digestibility and gas production between treatments. However, the highest ammonia concentration (p < 0.05) was observed in C and D feeds. The low acetate to propionate ratio observed in C feeds (p < 0.01) suggested that this feed had high starch based carbohydrates that NFC degrading bacteria used to produce more propionate. It is important to provide nutritional information to farmers so that they can select the appropriate commercial feeds to suit their own feeding strategies. This study might give supporting information to farmers for a more educated, and better, selection of feeds. Further in vivo studies should be conducted to evaluate the effects of different commercial feeds on growth performances in late finishing Hanwoo steers.