임의의 단면과 지점을 갖고 임의의 하중을 받는 보나 탑의 진동해석 방법이 발표된 바가 있다. 이러한 진동해석을 위하 여 처짐의 영향을 고려한 다양한 방법이 검토되었다. 본 연구에서 얻은 결과를 보 이론과 비교하였다. 이러한 목적으로 본 논문에서는 유한차분법을 사용하였다. 고유진동수에 대한 D 22 탄성계수의 영향을 철저히 검토하였다. 본 논문에서는 구조부재의 고유진동수와 적용 하중의 크기에 대한 관련성을 연구하였으며 그 결과를 제시하였다. 본 논문에서는 특별 직교이방성 판이론 이용하여 강교량과 철근콘크리트 슬래브 교량에 적용하여 을 해석하였으며 그 결과를 제시하였다.

Safety and health related information for the proper use and handling of pesticides is usually printed on the surface of the pesticide products (bottle type or bag type) in the form of texts. But, the guidelines or standards for the appropriate presentation of the texts for the pesticide products are most vague or not practical. Thus, this study aimed to provide the preliminary guidelines for the text sizes based on the legibility experiments. Total twenty subjects from two age groups (young: n=10, old: n=10, five males and five females in each group) participated in the experiment. First, subjects read the text cards presented in the distance of 50cm from the eyes of the subjects. Eight different text card sets were prepared for different font type(thick gothic-type and fine gothic-type), thickness of font(plain and bold), and number of syllables (2 and 3 syllables). When subjects read the cards, the correctness of reading (correct or wrong) was recorded and the degree of discomfort (from 1: no discomfort at all to 4: can't read at all) was also evaluated for all the text sizes. Results showed that the character size should be 4 pt or larger for the young subjects to read at least one word correctly in all the text conditions. For the old subjects to read at least one word correctly, the character size should be five pt or larder. The average of the minimum character sizes for 100% correct answer is 6.1 pt for young subjects and 10.5 pt for old subjects, respectively.

본 연구는 멸종위기식물인 단양쑥부쟁이(Aster altaicus var. uchiyamae)의 개체군을 대상으로 유전다양성을 유지하는데 필요한 최소개체수를 산정하기 위하여 수행되었다. 단양쑥부쟁이가 분포하고 있는 네 지역에서 각각 유전다양성 및 유전적 분화도를 분석하였다. AFLP(amplified fragment length polymorphism) 마커를 이용한 유전적 변이의 분석결과, 총 4개의 프라이머 조합에 대해서 936개의 밴드가 확인되었으며, 그 중 934개의 밴드(99.8%)가 다형성을 보여주었다. 단양쑥부쟁이 개체군 내에서 유전다양성(PPB = 45.3%, h = 0.104, I = 0.168, hs = 0.108)은 높은 수준으로 나타났으며, 개체군 간 유전적 분화도(GST = 0.075, θB = 0.079)는 낮은 수준이었다. AMOVA(Analysis of molecular variance)분석 결과에서도 전체 유전적 변이 중 91%가 개체군 내에서 보이는 반면, 9%는 개체군 간 변이에 기인한 것으로 나타났다. 단양쑥부쟁이 개체군에서 보이는 유전적 특성은 개체군 간의 빈번한 유전자 이동에 기인한 것으로 사료된다. 최대화 전략법에 의하여 경기도 여주일대의 3개 개체군을 대상으로(굴암, 도리섬, 삼합) 개체군 내 최소개체수를 산정한 결과 도리섬개체군에서는 17개체, 삼합개체군에서는 16개체, 굴암개체군에서는 11개체로 파악되었다. 단양쑥부쟁이 개체군의 최소개체수에 대한 정보는 효율적인 현지 외 보전을 위한 가이드라인을 제시해 줄 수 있다.

딸기 묘의 크라운 크기가 정식 후 식물체 생육 및 과실의 수량에 미치는 영향에 관하여 알아보고자 하였다. 묘 크기의 기준은 크라운 직경의 크기로 하여 3등급으로 구분하였으며, A등급 묘는 9.0 mm이상, B등급 묘 8.0∼8.9 mm, C등급 묘 8.0 mm이하로 하였다. 정식기 묘의 크라운 크기가 클수록 정식 후 뿌리 활착 및 식물체 생육이 좋았고, 개화기도 빨랐다. 정화방 첫 꽃 개화기는 A등급 묘가 B등급, C등급 묘에 비해 10일, 평균 개화기는 2∼3일 정도 빨랐다. A등급 묘의 1주당 4월까지 누적수량은 481 g, B등급 445 g, C등급 422 g 으로서, 크라운 직경이 가장 큰 A등급 묘는 B등급, C등급 묘에 비해 각각 8.1%, 13.9% 증수되었고, 2월까지의 초기수량은 A등급 묘가 B, C등급 묘에 비해 각각 23.3%, 39.1% 많았다.

유기용매와 초임계유체를 사용하여 대두분말에서 지방성분을 추출하는 공정에서 분말화공정(분쇄)의 시간의 변화에 따른 입자도와 초고압처리에 의한 추출속도를 측정하였다. 대두분말의 입자가 작을수록 추출속도가 향상되었으면 이는 입자의 크기가 작아짐에 따라 전체적인 표면적이 증가하여 고-액추출에서 중요한 반응기작인 물질전달속도를 증가시켰기 때문이라 판단된다. 초고압공정을 적용 시 동일한 입자크기에서 추출속도가 현저히 향상되었으며 이는 대두분말 내부에서 발생하는 확산현상에 대한 저항이 초고압상태에서의 변화로 감소되었기 때문이라 사료된다. 초임계유출에 의한 추출은 수율이 낮은 단점이 있으나 입자의 크기가 큰 상태에서는 초고압처리를 전처리로 사용할 경우 시간당 추출량을 상당부분 증가시킬 수 있음을 보여주었으나, 입자크기가 작을 경우 초고압처리가 영향을 미치지 못함을 보여주었다.

This study was performed to develop a video based system which can be used to measure the averaged fish size in a non-intrusive fashion. The design was based on principles of simple stereo geometry, incorporated fish dimensions weight relationships and took into consideration fish movement to lower system costs. As the fish size is an important factor that impacts the economy of an aquaculture enterprise. Size measurements, including fork length, width or height, girth, thickness and mass, can be used to determine fish condition in the fish farm, so the averaged fish size of fish cage needs to consistently monitor in open ocean aquaculture cage. A precision of ±3% for replicate length measurements of a 60cm bar is obtained at distances between 2.0 and 6.0m, and the mean fork length and mean swimming speed of bluefin tuna were estimated to 48.8cm and 0.78FL/s, respectively.

In the current study, the effects of particle size on compaction behavior of water-atomized pure iron powders are investigated. The iron powders are assorted into three groups depending on the particle size; 20-45 , 75-106 , and 150-180 for the compaction experiments. The powder compaction procedures are processed with pressure of 200, 400, 600, and 800 MPa in a cylindrical die. After the compaction stage, the group having 150-180 of particle size distribution shows the best densification behavior and reaches the highest green density. The reason for these results can be explained by the largest average grain size in the largest particle group, due to the low plastic deformation resistance in large grain sized materials.

Experimental fishing was carried out to compare the catches of main species and bycatch according to the codend mesh size (raschel, 15mm, 25mm, 35mm, 45mm) of stow net on anchor in the coastal waters of Seocheon after manufacturing five kinds of fishing gears and commercial fishing boat (7.93 tons) was used for it. Anchovy (Engraulis japonicus), southern rough shrimp (Trachysalambria curvirostris), beka squid (Loligo beka), cuttle fish (Sepia esculenta), swimming crab (Portunus trituberculatus) were dominant on the five kinds of experimental fishing gears. Southern rough shrimp was caught from all kinds of fishing gears and catches of anchovy was highest in the raschel codend, southern rough shrimp for 15mm, 25mm, 35mm codend and beka squid for 45mm codend. Bycatch proportion against total catches was 623,376g (28.7%) for 2,171,844g in raschel, 11,932g (1.7%) for 704,451g in 15mm, 3,616g (1.6%) for 221,432g in 25mm, 9,276g (4.9%) for 191,052g in 35mm and 2,724g (5.3%) for 51,431g in 45mm.

콜레마니진디벌(Aphidius colemani)은 진딧물과의 생물적 방제자로서 전세계적으로 널 리 이용되고 있으며, 경제적으로도 대단히 가치가 높은 분류군이다. 그러나 인위적으로 동일 한 숙주에서 수 세대에 걸쳐 누대사육 될 경우 이들의 형태적 유연성은 감소하고, 숙주의 생리 적 질에 따라 크기와 충질에서도 많은 차이를 나타내게 된다. 또한 숙주 선택 행동은 natal host로 부터 비롯된 표현형적 한계로 인해 제약을 받고, 공급되는 숙주의 령기 편차에 따라 기 생률은 현저한 차이를 보인다. 본 연구의 목적은 대량사육 되는 콜레마니진디벌의 도태를 방지하고 생물적 방제에 적합 한 품질을 지속적으로 유지시키기 위한 방법을 모색하는 것으로, natal host의 인위적 조절로 인해 발생하는 현상을 확인하는 것이다. 이에 본 연구에서는 서로 다른 두 natal host 종에서 발생한 콜레마니진디벌 개체군을 대상으로 이들의 크기 변화를 측정하고 복숭아혹진딧물 (Myzus persicae)에 대한 각각의 산란력, 성충 크기에 따른 숙주의 크기 선호성, 그리고 두 콜 레마니진디벌 개체군이 혼합되었을 때 생산량의 차이를 확인하였다. 온도 25℃, 상대습도 70%RH, 광조건 16L:8D에서 복숭아혹진딧물에 대한 콜레마니진 디벌의 일일산란력(eggs/1 female/1 day)을 조사한 결과, natal host가 복숭아혹진딧물인 콜 레마니진디벌은 66.4±33.9eggs, 아카시아진딧물(Aphis craccivora)인 콜레마니진디벌은 111.2±51.0eggs으로 전자보다 산란력이 높은 것으로 확인되었다. 기생자의 성충 크기에 따 른 숙주 크기 선호성에 대해 조사한 결과, 복숭아혹진딧물에서 발생한 콜레마니진디벌 개체 군의 평균 hind tibia 길이는 433.2±26.5㎛로 몸길이가 0.85±0.22㎜인 복숭아혹진딧물을 선호하였으며, 아카시아진딧물에서 발생한 콜레마니진디벌의 hind tibia 길이는 516.1±24.0 ㎛로 1.21±0.26㎜ 크기를 선호하는 것으로 나타났다. 따라서 natal host에 따라 콜레마니진 디벌의 성충 크기는 차이가 있으며, 이들의 크기와 비례하여 숙주 크기 선호성 또한 차이가 있음을 확인하였다. 이와 같은 특성을 이용하여 두 개체군이 혼합된 콜레마니진디벌을 복숭 아혹진딧물에 기생시킨 결과 0.13㎥ 크기의 사육 cage에서 55,000 마리의 콜레마니진디벌 이 생산되었으며, 이는 혼합하지 않은 두 대조군 보다 약 30% 많은 개체수로 확인되었다. 본 연구의 결과, 콜레마니진디벌의 대량 생산 체계에 있어 natal host의 인위적 변경은 콜레마 니진디벌의 생리적 특성 및 충질을 변화시켜 산란력과 생산력을 증진시킬 수 있는 중요한 요 소가 되는 것으로 판단된다.

Ni 8 wt.%-doped tin oxide (SnO2) thick films were fabricated into gas sensors by the method of screen printing onto alumina substrates. The particle size of SnO2 was controlled by changing the ball-mill time between 0~120 h. The structural and morphological properties of these thick films were investigated using X-ray diffraction and scanning electron microscopy. The structural properties of SnO2 powders showed a tetragonal phase with (110) dominant orientation. The particle size of the SnO2:Ni powders after ball-mill of 120 h was about 0.05 μm. The gas sensitivity (S = Rg/Ra) to 5 ppm CH4 gas and CH3CH2CH3 gas was measured at room temperature by comparing the resistance in air (Ra) with that of the target gases (Rg). The sensitivity of the SnO2 gas sensors was enhanced by increasing the ball-mill time. There was an association between the sensitivity of both the CH4 gas and the CH3CH2CH3 gas and the particle size of the SnO2. SnO2 gas sensors prepared by 72 h ball-mill showed a sensitivity of about 13 to 5 ppm CH4 gas and CH3CH2CH3 gas. The response time of the SnO2:Ni gas sensors to the CH4 gas was about 20 seconds.

In order to investigate the cause and magnitude of scale effect occurring in the model experiments of fishing nets, five pairs of Nylon pyramid nets and one pair of PE ones in which all the two nets paired were equal each other in the factors determining their flow resistance, i. e., the ratio d/l of diameter d to length l of bars, the angle f between two adjacent bars, the attack angle q of nettings to the water flow, and the wall area S of nets, and different in the values of d and l were prepared. Then, the nets were attached to the circular steel frame alternately and their flow resistances with shapes in water were measured on the sea ascribing no turbulent flows by using the tension meter made of a block bearing for the experiment. All the Nylon nets were spreads out easily in water to form a circular cone at relatively low velocity of water and showed the resistance smaller a little in the nets with larger d and l than them with smaller d and l, because the filtration of water through meshes become easier in nets especially with larger l. But PE nettings were not spread out sufficiently on account of their small flexibility and showed higher resistance especially in them with thicker twines. Therefore, the difference in bar length or mesh size and flexibility of nettings between prototype and model nets are regarded to become factors ascribing scale effect. Especially the influence of the difference in mesh size may become large significantly in actual model experiments because the mesh size of model nets is decided at much larger value than that given by scale ratio and so the difference of mesh size between the two nets become much larger than that between nets used in this experiment.

This work presents a fabrication procedure to make large-area, size-tunable, periodically different shape metal arrays using nanosphere lithography (NSL) combined with ashing and annealing. A polystyrene (PS, 580 μm) monolayer, which was used as a mask, was obtained with a mixed solution of PS in methanol by multi-step spin coating. The mask morphology was changed by oxygen RIE (Reactive Ion Etching) ashing and temperature processing by microwave heating. The Au or Pt deposition resulted in size tunable nano patterns with different morphologies such as hole and dots. These processes allow outstanding control of the size and morphology of the particles. Various sizes of hole patterns were obtained by reducing the size of the PS sphere through the ashing process, and by increasing the size of the PS sphere through annealing treatment, which resulted in tcontrolling the size of the metallic nanoparticles from 30 nm to 230 nm.

The purpose of this study was to compare torso pattern made by draping and flat pattern method in terms of the size of breast. The size of this study was classified as 75A and 75D according to the size of breast. Each torso pattern by the combination of the size and pattern method was compared and analyzed. In order to test the fit of the draping and flat pattern that was developed according to the size of breast, the outer appearance was evaluated. The results of the study were as follows: First, The most striking size difference was difference between the front and the back on bust line level, which decides on position of the side seam in comparison of size between draping and flat pattern of 75A and 75D. In the flat pattern, the difference between the front and the back in the size of breast was consistent regardless of a change in the size of breast. However, in the draping, the bigger breast led to the bigger difference between the front and the back on bustline level. Second, the flat pattern in 75D was evaluated to be the worst in 27 items among total 46 items for the evaluation of outer appearance in the draping and flat pattern of 75A and 75D. Third, regardless of size, the draping was evaluated to be more suitable in the areas related to neck, arm hole, and waist dart than the flat pattern. These results are suggesting that the draping is a method of reflecting characteristic of the body type more accurately than the flat pattern, and that the draping is a more suitable method than the flat pattern for the design of clothing pattern of the body type with big breast like 75D.

Recently, Fishermen have required to expand the circumference of trap entrance for conger eel because it was difficult to take the catch out as well as to put the baits into. A series of fishing experiments was carried out in coastal areas of Tongyoung, Korea in 2008 and 2009 using the traps to describe the effect of the entrance size on the catch. The experimental traps (five types) were used in filed experiments with four types circumference size traps (140, 180, 220 and 260mm) with mesh size 22mm and another type was used the same one usually using in filed with mesh size 35mm (750mm circumference). The experiment results were, the conger eels of total length 35mm more or so were caught 85, 93, 142 and 176 individual by the experiment traps with mesh size 22mm as increase circumference size from 140mm to 260mm, respectively. And the small conger eels of the total length below 35mm to be prohibited to catch by law were caught 145, 160, 288 and 304 individual according to increase the circumference size of trap, respectively. In addition, in case of the trap with mesh size 22mm, bycatches were 230 - 260 individuals and much more than bycatches of the trap with mesh size 35mm. In conclusion, when we expand the circumference size of trap according to fishermen's requirement, we should review not only economic of fishery but also increasement the bycatch of non-target fishes and small size fishes.

In this research, the optimal manufacturing conditions of fine Si powders from Si scrap were investigated as a function of different initial powder size using the high-energy ball milling equipment, which produces the fine powder by means of an ultra high-energy within a short duration. The morphological change of the powders according to the milling time was observed by Scanning electron microscopy (SEM). With the increasing milling time, the size of Si powder was decreased. In addition, more energy and stress for milling were required with the decreasing initial powder size. The refinement of Si scrap was rapidly carried out at 10min ball milling time. However, the refined powder started to agglomerate at 30 min milling time, while the powder size became uniform at 60 min milling time.