Axial flow fan under certain condition may stall. The rise in pressure across the impeller blade of an axial flow fan depends on the angle of attack. At a low back pressure, the air volume will be large and the angle of attack is small. In this study, the time dependent Navier-Stokes equations are numerically solved in large size axial-flow fan with groove

The purpose of this study is to predict the economic size of foods-for-elderly market, which will be valuable information for establishing related policy and backup system. After setting the scope of related industry, detailed information for current market situation was investigated and a systematic forecast for market changes in the future was performed. Economic growth, changes in consumer expenditure and economic status of the elderly, current subscription of medical insurance and saving for pension were reflected. In addition, a survey toward related firms was completed and changes in aged population and incidence of chronic disease in the elderly were taken into account. Results show that the annual growth rate of the market was predicted to be the minimum 4.54% through the maximum 8.32% from 2010 to 2025 and its market size was forecasted to be the minimum 7,073 ten million won through the maximum 10,976 ten million won. It is expected that the market of foods-for-elderly will grow rapidly with development of foods technology and fast increase of aged population. Especially, growth of health functional foods and foods for special dietary uses for elderly will be distinguished. However, it seems that related firms are on the hedge, watching current trend of the related industry. This may results in insufficient supply against the demand. Therefore, policy for foods-for-elderly should be introduced and systematically administered, including R&D support, standardization and authentication for foods-for-elderly, construction of related database system.

A net-assembling company for gill net fishing gears makes a design based on the size of nets provided and determines floats, types of weights, and numbers. In addition, through the accurate examination of net weights in the process of fishing gear designing, it can prevent an excessive use of designing costs. The weight of twine can be easily calculated by its thickness differences, but the weight of netting has errors to be calibrated since the weight of netting is not changing exponentially with the changes of number and size of meshes. This study aims to suggest and empirically analyze the methods for estimating the weights of netting in accordance with the changes of number, size and thickness of meshes for a sound management of netting and net-assembling companies. Results indicated that the method using the knots and legs of netting was not practically usable because the errors were increased as the number of mesh increased. However, the method using netting area shown its usage potentiality with the calibration of the increasing ratio of mesh numbers.

Most useful statistical techniques in six sigma DMAIC are hypothesis testing and interval estimation. So this paper reviews and derives sample size formula by considering significance level, power of detectability and effect difference. The quality practioners can effectively interpret the practical and statistical significance with the rational sample sizing.

본 연구는 한국에 서식하는 장지뱀과 3종인 표범장지뱀(Eremias argus), 아무르장지뱀(T. amurensis), 줄장지뱀(T. wolteri)의 외부 형질에 대한 성적 크기 차이(SSD)를 알아보기 위하여 수행되었다. 외부 형질 중 주둥이-항문 길이, 꼬리 길이, 머리 길이, 머리 폭, 앞다리 길이, 뒷다리 길이와 같은 6개 부위를 중심으로 수컷과 암컷을 비교하였다. 머리-항문 길이는 student's t 검정을, 나머지 부위는 머리-항문 길이를 공변량으로 이용하여 공분산 검정을 수행하였다. 머리 길이와 꼬리길이는 일반적인 장지뱀과의 특성과 마찬가지로 한국산 장지뱀과 3종 모두 수컷이 암컷보다 긴 것으로 나타났다. 추가적으로 표범장지뱀은 머리 넓이, 앞다리 길이, 뒷다리 길이, 줄장지뱀은 머리 넓이에서 수컷이 암컷보다 길었다. 머리-항문 길이는 한국산 장지뱀과 3종 모두 암 수 사이에서 유의한 차이가 없었다. 머리-항문 길이의 SSD의 원인을 파악하기 위해서는 수컷간의 싸움과 암컷 머리-항문 길이와 한 배 산란수의 관계와 같은 생태학적 정보가 필요하다. 한국산 장지뱀과 3종에 대한 생태학적 연구가 계속 진행된다면 SVL에서 SSD가 일어나지 않은 이유를 설명할 수 있을 것이다.

This paper reports the microstructures and thermal conductivities of -SiC composite ceramics with size and amount of SiC. We fabricated sintered bodies of -x vol.% SiC (x=10, 20, 30) with submicron and nanosized SiC densified by spark plasma sintering. Microstructure retained the initial powder size of especially SiC, except the agglomeration of nanosized SiC. For sintered bodies, thermal conductivities were examined. The observed thermal conductivity values are 40~60 W/mK, which is slightly lower than the reported values. The relation between microstructural parameter and thermal conductivity was also discussed.

Actias artemis is a members of the family Saturniidae, also known as wild silkmoths, have impressive color and size. In 2012, estimation of Actias artemis (Lepidoptera: Saturniidae) abundance in HECRI was conducted using the mark-release-recapture (MRR) method (Jolly, 1965) from mid to late May. Seven sampling events were accomplished from 19 May, 21 May, 22 May, 24 May, 26 May, 28 May and on 30 May, during the main flight of the species. Marking was made by writing numbers in the hind wing of each individual moths. Most collections were undertaken by a team of experienced four or six researches of HECRI using light trap (mercury lamp: 250W). Seven female and 58 male moths were captured in study site. The effective population size of Actias artemis was 24.9 and heterozygosity was more than 97%. Seven marked moths were recaptured, resulting in 9.7% of recapture rate. The estimated population size of A. artemis showed a peak by 133 individuals on 22 May and then declined. The estimated adult numbers of A. artemis using MRR method from minimum 168 to maximum 5,332 (p<0.05).

금강수계 백곡천 상류에 서식하는 미호종개(국가 천연 기념물)를 대상으로 형광물질 주입에 의한 다중표지-재포 획법(졸리-시바모델적용)으로 개체군 크기를 추정하였다. 총 어류조사지점은 335개였고, 그 중 미호종개가 출현 지 점은 217개 였다. 본 연구에서 추정한 미호종개 평균 개 체군 크기는 6,143개체였다. 이는 2009년 환경부에서 수행한 미호종개 개체군 규모와 비교 했을때보다 41% 감 소된 것이다. 백곡천에서 본 종의 감소는 미소서식지 훼 손, 퇴적물, 서식환경의 악화 등의 영향으로 판단된다. 따 라서 백곡천 본 종의 개체군 회복 미소서식지 보호를 위 해 서식지복원 프로그램이 요구된다.

Male factor infertility or sub-fertility contributed half of all cases of infertility while the semen abnormality is the current topic of argument. Conventional analysis of semen showed poor correlation with fertility. Therefore, evaluation of current semen analysis method is necessary to improve standards of semen assessment. The goal of this study was to investigate that correlation between motion kinematic before and after capacitation and litter size in porcine. Sperm motility and kinematics were measure by computer-assisted sperm analysis (CASA). The motility of spermatozoa was positively correlated with curvilinear velocity (VCL), average path velocity (VAP), and mean amplitude of head lateral displacement (ALH) (p<0.05). Where as VCL positively correlated with VSL, VAP and ALH (p<0.01). Straight-line velocity (VSL) was positively correlated with VAP and ALH (p<0.01). VAP was significantly positively correlated with ALH (p<0.01). Also, we found significant positive correlation among variation of VSL, VAP and ALH (p<0.05). No motility and kinematic parameter are correlated with litter size. However, litter size was significantly correlated with breed (p<0.05). Our results suggested that analysis of sperm motility and kinematics using CASA is questionable for prediction of litter size. However, it has some practical importance to evaluate semen commercially.

오리엔탈나리 ‘Siberia’ 품종 조직배양구를 이용하여 생산된 소구 및 중구를 강원지역 고랭지(인제)와 평난 지(강릉)의 무가온하우스에 정식하였을 때 정식한 구근 크기와 재배지역에 따라 구근비대 정도를 조사 분석하 여 향후 나리 종구 생산의 예측가능한 구근생산모델을 제시하고자 본 시험을 실시하였다. 인제지역(해발 500 m)에서 재배된 것이 평난지 보다 종구 생존율, 구 주가 크고, 구중이 무겁고, 자구수가 많아 효과적이었 다. 인제지역에서 구근 크기별로 정식한 후 180일간 재배하여 수확한 구근의 비대 결과, 구주(구근둘레) 4.0-5.9 cm 크기의 구근을 정식하였을 때 수확한 구근 크기는 10.8-11.3cm, 구중은 19.5-23.4 g, 구주 6.0- 8.9 cm 크기의 구근 정식 시 수확 한 것은 12.5- 13.9 cm, 구중은 29.2-43.5 g, 9.0-10.9 cm 크기의 구 근 정식 시 수확한 것은 16.0-17.9 cm, 구중 58.9- 85.5 g의 구근을 생산하였다.

This study was operated to establish induction using ultrasonography by estimating the relation of follicle size and estrus manifestation. Clinical estrus symptoms were observed 97.4% in cows and 87.5% in heifers when overall 55 cows were induced to estrus in a single dose of after verifying CL through ultrasonography, which means estrus hours among those 52 cows showing the clinical estrus symptoms were estimated 2.39 days on cows and for 2.37 days on heifers which showed no differences (p>0.05). The estrus manifestation hours according to the follicle size in cows didn't have any significance each other (p>0.05), though estrus hours was 54 hours (the shortest) with follicle size bigger than 10 mm and were made up within 69 hours. The estrus manifestation hours according to the follicle size in heifers didn't have any significance each other (p>0.05) and took around 42 hours (the shortest) with follicle size of 5mm (the smallest) and were made up within 66 hours. Follicles after injection were ovulated and assigned to many phases as follows; Group 1 (growing phase) - continuously growing into ovulation, Group 2 (growing and static phase) - delaying in growth after the growth of follicles, Group 3 (static and growing phase) - growing after growth delay, Group 4 (regressing and new growing phase) - the follicle is closed and a new follicle grows. In addition, the process of follicle development and estrus hours had no significance each other (p>0.05), though estrus manifestation hours in Group 1 and 2 was relatively short, and in Group 3 and 4 for a relatively long time. In the result of all above, the estrus manifestation hours after injection has no differences accoring to the follicle size in cows and heifers. Therefore, High pregnancy rate is obtained when practicing artificial insemination within 3 days in estrus or TAI in 72 to 80 hours after adminitrating .

30종의 초 중 고 및 대학교 교과서에 나타난 퇴적물의 입도에 대한 한국어 용어를 비교 검토하고 문제점과 대안을 제시하였다. 교과서에 나타난 퇴적물의 입도에 대한 한국어 용어는 거의 모두 Udden-Wentworth의 분류를 번역한 것으로, 교과서마다 다른 용어를 사용하고 있다. 자갈은 여러 교재에서 왕모래, 잔자갈, 왕자갈, 및 표력 또는 거력으로 나타내고 있으나, 이들은 각각 잔자갈(granule), 중자갈(pebble), 큰자갈(cobble), 및 왕자갈(boulder)로 나타내는 것이 적절한 것으로 생각한다. 자갈보다 작은 퇴적물은 '매우 고운', '고운', '중간', '굵은', 및 '매우 굵은'이라는 형용사를 각 퇴적물 이름 앞에 붙여서 표현하는 것이 적합한 것으로 생각된다. silt는 여러 교재에서 미사로 나타내고 있으나 실트로 표현하는 것이 적당하다고 판단된다. 실트와 점토의 혼합물인 mud는 대부분의 초등학교와 중학교, 그리고 일부 고등학교와 대학교 교과서에서 진흙으로 표현하고 있으나 한국지구과학 사전 등을 포함한 여러 교과서에서 쓰고 있는 바와 같이 이토(泥土)로 나타내는 것이 적당하다고 생각한다.

ZrN nanoparticles were prepared by an exothermic reduction of ZrCl4 with NaN3 in the presence of NaCl flux in a nitrogen atmosphere. Using a solid-state combustion approach, we have demonstrated that the zirconium nitride nanoparticles synthesis process can be completed in only several minutes compared with a few hours for previous synthesis approaches. The chemistry of the combustion process is not complex and is based on a metathesis reaction between ZrCl4 and NaN3. Because of the low melting and boiling points of the raw materials it was possible to synthesize the ZrN phase at low combustion temperatures. It was shown that the combustion temperature and the size of the particles can be readily controlled by tuning the concentration of the NaCl flux. The results show that an increase in the NaCl concentration (from 2 to 13 M) results in a temperature decrease from 1280 to 750˚C. ZrN nanoparticles have a high surface area (50-70 m2/g), narrow pore size distribution, and nano-particle size between 10 and 30 nm. The activation energy, which can be extracted from the experimental combustion temperature data, is: E = 20 kcal/mol. The method reported here is self-sustaining, rapid, and can be scaled up for a large scale production of a transition metal nitride nanoparticle system (TiN, TaN, HfN, etc.) with suitable halide salts and alkali metal azide.

붉은배새매(Accipiter soloensis)는 국내에서 가장 흔히 번식하는 맹금류에 해당함에도 불구하고, 이 종의 번식기 공간이용에 대한 정보는 부족한 실정이다. 붉은배새매의 번식기 세력권과 행동권을 파악하기 위하여 국내에서 번식하는 6쌍(2005년 4쌍, 2006년 2쌍)의 수컷을 6월부터 7월까지 관찰하였다. 이를 통해 수컷이 3회 이상 반복적으로 이용하는 주요 지점과 명확한 세력권 방어 행동을 보이는 지점을 확인하고, 이를 GIS 프로그램으로 분석하였다. 확인된 25.2±5.3개 지점을 중심으로 100% 최소다각형법(minimum convex polygon)을 이용하여 분석한 결과, 붉은배새매의 번식기 세력권은 4.62±0.90 ha, 행동권은 22.57±5.12 ha에 해당하는 것으로 나타났다. 본 연구에서 확인된 붉은배새매의 세력권과 행동권은 비록 기존에 보고된 값보다 넓었으나, 전체 번식기에 걸쳐 이용하는 절대적인 공간 규모가 여전히 작다는 점을 보여준다. 이는 붉은배새매가 먹이를 제공할 수 있는 좁은 서식지, 특히 0.6-2.0 ha에 불과한 논에서 발생할 수 있는 환경 변화나 자원 고갈에도 상당히 취약할 수 있다는 것을 의미한다. 본 연구는 관찰을 통한 세력권 추정에 해당하지만, 붉은배새매의 보전과 관리, 향후 연구를 위한 기초연구로서의 중요성이 있다고 판단된다.