• Journal of Sport and Applied Science
• /
• 제6권4호
• /
• pp.11-23
• /
• 2022

New insights into the aetiology of anaemia in athletes have been discovered in recent years. From hemodilution and redistribution, which are thought to commit to so-called "sports anaemia," to iron deficiency triggered by higher requirements, dietary requirements, decreased uptake, enhanced losses, hemolysis, and sequester, to genetic factors of different types of anaemia (some related to sport), anaemia in athletes necessitates a careful and multisystem methodology. Dietary factors that hinder iron absorption and enhance iron bioavailability (e.g., phytate, polyphenols) should be considered. Celiac disease, which is more common in female athletes, may be the consequence of an iron deficiency anaemia that is unidentified. Sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis are all ways iron is lost during strength training. In training, evaluating the iron status, particularly in athletes at risk of iron deficiency, may work on improving iron balance and possibly effectiveness. Iron status is influenced by a healthy gut microbiome. To eliminate hemolysis, athletes at risk of iron deficiency should engage in non-weight-bearing, low-intensity sporting activities.

• Journal of Electrical Engineering and Technology
• /
• 제1권2호
• /
• pp.216-225
• /
• 2006

This paper presents a new circuit topology of DC busline switch and snubbing capacitor-assisted full-bridge soft-switching PWM inverter type DC-DC power converter with a high frequency link for low voltage large current applications as DC feeding systems, telecommunication power plants, automotive DC bus converters, plasma generator, electro plating plants, fuel cell interfaced power conditioner and arc welding power supplies. The proposed power converter circuit is based upon a voltage source-fed H type full-bridge high frequency PWM inverter with a high frequency transformer link. The conventional type high frequency inverter circuit is modified by adding a single power semiconductor switching device in series with DC rail and snubbing lossless capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge inverter arms and DC busline can achieve ZVS/ZVT turn-off and ZCS turn-on commutation operation. Therefore, the total switching losses at turn-off and turn-on switching transitions of these power semiconductor devices can be reduced even in the high switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules is selected to be 60 kHz. It is proved experimentally by the power loss analysis that the more the switching frequency increases, the more the proposed DC-DC converter can achieve high performance, lighter in weight, lower power losses and miniaturization in size as compared to the conventional hard switching one. The principle of operation, operation modes, practical and inherent effectiveness of this novel DC-DC power converter topology is proved for a low voltage and large current DC-DC power supplies of arc welder applications in industry.

• Journal of Animal Science and Technology
• /
• 제47권3호
• /
• pp.371-378
• /
• 2005

This study was conducted to evaluate effects of dietary herbal extracts mixturetMiracle" included Angelicae Gigantis Radix, Rehmanniae Radix, Cnidii Rhizoma, Glycyrrhizae Radix, Schizandrae Fructus, Plantago asiatica and Dioscoreae Radix) on the productivities of lactating sowsand growth performance and hematological characteristics of piglets. Twenty seven sows (Yorkshire ${\times}$ Landrace ${\times}$ Duroc, 1 to 3 parities) were used in a 21 day old trial. Dietary treatments included 1) CON (control; basal diet), 2) HPMO.l (basal diet + herbal plant mixture 0.1 %) and 3) HPMO.2 (basal diet + herbal plant mixture 0.2 %). Backfat thickness losses from farrowing to weaning was decreased in HPM treatmentscompared with control(linear effect, P $\leq$ 0.003). ADFI was decreased in sows fed herbal plant mixture(linear effect, P < 0.05). Also, treatments of dietary herbal plant mixture reduced day of return to estrus compared with control(linear effect, P < 0.05). Energy digestibility in HPM treatments were higher than control(linear effect, P $\leq$ 0.05). In piglets, weight gain(P > 0.05) and survivability(P> 0.05) after weaning werenot affected by treatments. No statistical differences were found(P> 0.05) forhematological characteristics in piglets. In conclusion, dietary herbal plant mixture reduces backfat thickness losses and day of return to estrus and improves energy digestibility in lactating sows.

• Journal of Biosystems Engineering
• /
• 제23권3호
• /
• pp.229-244
• /
• 1998

This study was performed to determine proper fan and heater management schemes for natural air drying of rough rice in round steel bin with stirring device under Korean weather conditions. A computer simulation model was developed to predict moisture content changes, energy requirements, and drymatter losses during drying of rough rice by natural air. Drying test was conducted to validate the simulation model using round steel bin of holding capacity of 300ton at Rice Processing Complex in Jincheon. The bin was filled with rough rice every day and mixing by stirring device. Moisture contents, ambient air temperatures, relative humidities, static pressures in plenum chamber in the bin, airflow rates, and electrical and fuel energy were measured. Relative errors of moisture content changes predicted by the simulation model were below 5ft, and relative errors of final moisture content, final grain weight, required energy ranged from 0.9% to 6%. These not levels indicated that the simulation model can satisfactorily predict the performance factors of natural air drying system such as drying rates and energr consumptions comparing error level of 10% to 15% in other drying simulation models generally used in dryer desists. Twelve different fan and heater management schemes were evaluated using the computer simulation model based on three hourly weather data from Suweon for the period of 1952-1994. The best management schemes were selected comparing the drymatter losses, required drying times, required energy consumptions. Operating fan without heating only when ambient relative humidity was below 85% or 90% appeared to be the most effective method of In operation in favorable drying weather. Under adverse drying climates or to reduce required drying time, operating fan continuously, and heating air with $1.5^{\circ}C$ temperature rise only when ambient relative humidity was over 85% appeared to be the most suitable method.

• 한국수소및신에너지학회논문집
• /
• 제27권6호
• /
• pp.642-650
• /
• 2016

One of the most feasible solution for reducing the excessive energy consumption and carbon dioxide emission is usage of more efficient fuel such as hydrogen. As is well known, there are three viable technologies for storing hydrogen fuel: compressed gas, metal hydride absorption, and cryogenic liquid. In these technologies, the storage for liquid hydrogen has better energy density by weight than other storage methods. However, the cryogenic liquid storage has a significant disadvantage of boiling losses. That is, high performance of thermal insulation systems must be studied for reducing the boiling losses. This paper presents an experimental study on the effective thermal conductivities of the composite layered insulation with aerogel blankets($Cryogel^{(R)}$ Z and $Pyrogel^{(R)}$ XT-E) and Multi-layer insulation(MLI). The aerogel blankets are known as high porous materials and the good insulators within a soft vacuum range($10^{-3}{\sim}1$ Torr). Also, MLI is known as the best insulator within a high vacuum range(<$10^{-6}{\sim}10^{-3}$ Torr). A vertical axial cryogenic experimental apparatus was designed to investigate the thermal performance of the composite layered insulators under cryogenic conditions as well as consist of a cold mass tank, a heat absorber, annular vacuum space, and an insulators space. The composite insulators were laminated in the insulator space that height was 50 mm. In this study, the effective thermal conductivities of the materials were evaluated by measuring boil-off rate of liquid nitrogen and liquid argon in the cold mass tank.

• Animal Bioscience
• /
• 제35권7호
• /
• pp.1100-1108
• /
• 2022

Objective: The objective of this study was to evaluate the effect of waste cooking oil (WCO) addition on ammonia (NH₃) emissions during the composting of dairy cattle manure under two aeration conditions. Methods: The composting tests were conducted using the laboratory-scale composting apparatuses (14 L of inner volume). Three composting treatments (Control, WCO1.5, and WCO3, with WCO added at 0 wt%, 1.5 wt%, and 3 wt% of manure, respectively) were performed in two composting tests: aeration rate during composting was changed from 0.55 to 0.45 L/min in Test 1, and fixed at 0.3 L/min in Test 2, respectively. The NH₃ emitted and nitrogen losses during the composting were analyzed, and the effect of the addition of WCO on NH₃ emissions were evaluated. Results: Both tests indicated that the composting mixture temperature increased while the weight and water content decreased with increasing WCO content of the composting mixtures. On the other hand, the NH₃ emissions and nitrogen loss trends observed during composting in Tests 1 and 2 were different from each other. In Test 1, NH₃ emissions and nitrogen losses during composting increased with increasing WCO contents of the composting samples. Conversely, in Test 2, they decreased as the WCO contents of the samples increased. Conclusion: The WCO addition showed different effect on NH₃ emissions during composting under two aeration conditions: the increase in WCO addition ratio increased the emissions under the higher aeration rate in Test 1, and it decreased the emissions under the lower aeration rate in Test 2. To obtain reduction of NH₃ emissions by adding WCO with the addition ratio ≤3 wt% of the manure, aeration should be considered.

• 한국동물생명공학회지
• /
• 제38권3호
• /
• pp.158-166
• /
• 2023

Background: Copy number variation (CNV) can be identified using next-generation sequencing and microarray technologies, the research on the analysis of its association with meat traits in livestock breeding has significantly increased in recent years. Hanwoo is an inherent species raised in the Republic of Korea. It is now considered one of the most economically important species and a major food source mainly used for meat (Hanwoo beef). Methods: In this study, CNVs and the relationship between the obtained CNV regions (CNVRs) can be identified in the Hanwoo steer samples (n = 473) using Illumina Hanwoo SNP 50K bead chip and bioinformatic tools, which were used to locate the required data and meat traits were investigated. The PennCNV software was used for the identification of CNVs, followed by the use of the CNV Ruler software for locating the different CNVRs. Furthermore, bioinformatics analysis was performed. Results: We found a total of 2,575 autosomal CNVs (933 losses, 1,642 gains) and 416 CNVRs (289 gains, 111 losses, and 16 mixed), which were established with ranged in size from 2,183 bp to 983,333 bp and 10,004 bp to 381,836 bp, respectively. Upon analyzing the restriction of minor alleles frequency > 0.05 for meat traits association, 6 CNVRs in the carcass weight, 2 CNVRs in the marbling score, 3 CNVRs in the backfat thickness, and 2 CNVRs in the longissimus muscle area were related to the meat traits. In addition, we identified an overlap of 347 CNVRs. Moreover, 3 CNVRs were determined to have a gene that affects meat quality. Conclusions: Our results confirmed the relationship between Hanwoo CNVR and meat traits, and the possibility of overlapping candidate genes, annotations, and quantitative trait loci that results depended on to contribute to the greater understanding of CNVs in Hanwoo and its role in genetic variation among cattle livestock.

• 유기물자원화
• /
• 제2권2호
• /
• pp.39-51
• /
• 1994

육계분을 pile의 내부온도 peak를 조절하여(조절 무, $70^{\circ}C$이하, $60^{\circ}C$ 이하 composting 처리시 공정기간에 걸친 물리.화학적인 성상 변화를 고찰하였다. Composting 에 이용된 구조물의 크기는 $1.0{\times}1.0{\times}1.2m$였다. 육계분은 공정 개시후 5~6주 경과시 암모니아취가 없고, 왕겨 크기의 입자로 분해된, 연한 갈색의 최종 생산물로 전환되었다. Compost 의 내부온도는 공정 개시후 3~4일경에 peak에 도달하였고, 이 후 서서히 감소하였다. 8주 경과시의 Compost 의 최종 함수율은 26.5% 였으며, pH는 9.0~9.1, C/N ratio는 14.0~14.3의 범위를 보였다. C/N ratio 의 증가는 N의 손실이 주 요인이었다. 최초 중량과 비교할 때, 공정 후 8주 경과시의 총 중량은 평균 38.8%, 건물 중량은 평균 64.1%, 유기물 중량은 평균 34.8% 정도였다. 계분 compost 의 함수율, pH, C/N ratio, 총 중량, 건물 중량, 유기물 중량은 내부온도 조절에 의하여 영향을 받지 않았다. 육계분 compost 는 공정 개시 후 5~6주 경과시에 물리.화학적 변화가 매우 적은 물질로 전환되었으며, 공정상의 N 손실을 사전 방지하여 composting 효율을 향상시키는 방안이 고려되어져야 할 것으로 사료되었다.

• 융합신호처리학회논문지
• /
• 제4권2호
• /
• pp.46-52
• /
• 2003

본 논문에서는, 디지털컨텐트(Digital Content)의 저작권 보호를 위한 워터마크(Watermark) 삽입방법으로 적응적 가중치를 가지는 Mask처리를 기반으로 하는 웨이브릿(Wavelet) 워터마킹(Watermarking)을 제안하였다. 워터마크가 원 영상에 첨가되는 잡음으로 볼 때, 영상의 질을 저하시키지 않고 삽입 가능한 워터마크의 크기는 한정적이다. 즉, 워터마크 삽입 과정에서 고려 할 용량성, 강인성 및 화질 특성 중 어느 한 가지라도 지나치게 크게 되면 다른 특성을 저하시키는 원인이 된다. 이런 문제를 해결하기 위해 적응 가중치 마스크 기반 워터마크 삽입 알고리즘을 적용하여 효율을 최적화하였다. 그 결과 워터마킹된 영상이 외부공격에 대하여 강인성 및 화질 특성으로 47dB 이상을 유지하였다. 또한 명도대비의 변형과 압축에 대한 외부공격에 대해 추출된 워터마크의 상관계수가 각각 0.8이상과 0.65이상을 유지함을 확인할 수 있었다.

• 대한수의학회지
• /
• 제36권2호
• /
• pp.313-325
• /
• 1996

Experiments were undertaken to examine the ability of selenium to protect against alcohol and/or paraquat-induced hepatotoxicity and to examine the additive effect between alcohol and paraquat. Protective effect against hepatotoxic functions was measured in serum from alcohol(15% v/v), paraquat(200ppm), alcohol and paraquat, and combination of sodium selenite(4ppm) in drinking water-fed guinea pigs ad libitum for 4 weeks. A total of 68 healthy 7-weeks-old male animals were assigned at random to 8 treatment groups(9~13 animals/group). Body and liver weight losses, and high serum concentrations in aspartate aminotransferase(AST), alanine aminotransferase(ALT, in only paraquat group), $\gamma$-glutamyltranspeptidase($\gamma$-GTP), cholesterol(Cho), creatinine, blood urea nitrogen(BUN), total bilirubin(TB), direct bilirubin(DB), total protein(TP), albumin and globulin as well as low values in alkaline phosphatase(ALP) and glucose were produced in a groups of alcohol or paraquat-fed. These values were not potentiated in a group given the combination of alcohol plus paraquat. Morphological changes in the liver were also observed in the alcohol or paraquat-fed group. Lipid droplet and cell swelling in the hepatocytes were observed in alcohol-fed guinea pig, especially Mallory's hyaline arounded hepatic vein. In the paraquat-fed guinea pig, lipid droplet, pyknosis and karyolysis were observed. When alcohol or paraquat was combined with selenium-fed, hyperplasia of Kupffer cell in liver were observed. However, the mean ALT, $\gamma$-GTP, Cho, BUN, TB, TP, albumin and globulin values were lower in groups given the combination of alcohol and/or paraquat plus selenium, compared with groups given alcohol and/or paraquat. Also, the ratio of liver weight to body weight and ALP values(exception of paraquat plus selenium group) were increased by selenium. These results suggest that an adequate selenium confers marked protection against alcohol and paraquat-induced hepatotoxicity.