• 한국재료학회지
• /
• 제19권9호
• /
• pp.473-480
• /
• 2009

In order to provide the mechanism of nozzle clogging, recovered nozzles for high strength steel grade were examined carefully after continuous casting. The thickness of clogged material in SEN is increased in the following order: from the bottom to the top of the nozzle, upper part of slag line, and the pouring hole. Nozzle clogging material begins to form due the adhesion of metal to nozzle wall, the decarburization, and reduction of oxide in the refractory by Al and Ti in the melt. The reduction of oxide in the refractory by Al and Ti improves the wettability of the melt on the refractory and forms a thin Al-Ti-O layer. Metal containing micro alumina inclusions is solidified on the Al-Ti-O layer, and the solid layer grows due to the heat evolution through the nozzle wall. Thermodynamic calculation has been made for the related reactions. The effect of superheat to the nozzle clogging is discussed on ultra low carbon steel and low carbon steel.

• 한국주조공학회지
• /
• 제30권4호
• /
• pp.130-136
• /
• 2010

Sulfide segregation behavior, characteristics of solidification microstructure and compositional distribution in the riser/castings junction of heavy-section main bearing support (MBS) steel castings were investigated; Sulfide streaks of A segregation were formed in the transitional region from columnar grain to coarse equiaxed grain and floated with aggregation of the dendritic free crystal. Solute segregation behaviors of elements Si, P and S were V shape negative segregation from the bottom of the castings to upper part of the riser with the reference of vertical center-line of the specimen block. Those of elements C and Mn were V shape negative segregation in the main body and A shape positive segregation in the riser of the casting. Just beneath the pipe shrinkage in the riser segregation ratio of each element was the highest, and that of S was 3.6 times higher, C 3.3 times, P 2.1 times, Si 1.6 times and Mn 1.0 times respectively. [Mn/S] ratio of the specimen block was distributed in the wide range of 20~275.

• 한국의류학회지
• /
• 제26권6호
• /
• pp.821-832
• /
• 2002

The purpose of this study was to develop grading method of the basic brassiere patterns therewith, provide for 12 size's brassiere patterns and prove fitness of their's and shape. The collected data were statistically processed using the SAS 6.12 for Means, Standard Deviation, etc. The results of this study can be summarized as follows; 1. The basic sizes adopted at the first design stage (see fig.1-2) were 75AA, 75A and 75B each of which was designed as upper foundation basic pattern in reference to the cup size. At the second stage, each of the upper body foundation basic pattern was used to design lower cup, upper up, front panel and wing in their order(see fig.3-6). At the third stage, the other sizes were graded in reference to the three brassiere patterns (75AA, 75A and 75B) to produce 12 brassiere sizes(see Tab. 7-8). In order to develop the basic patterns of adult women's brassieres, 33 women were selected per 11 size combination(3 women per size combination), and then, their brassiere fitting was teated. As a result, the fronts of the basic patterns were found to have such problems as undone front center, poor levelling of upper cup's bottom line or lower cup's top line, poor shape of upper cup's outside top line and shoulder strip position. On the other hand, on the rear side of the basic patterns, the central part of the wing was slightly lifted, while the wing width and straps'interval did not befit the ful1-cup brassiere. The result of this first brassiere fitting test showed that the functionality and aesthetics of the basic pattern brassieres were more or less satisfactory, and thus, the problems were addressed for the second teat. In the second test, the aesthetics, breast-shaping effect and functionality of the basic pattern brassieres were much improved. 2. We were to present the final brassiere sizing system to extend the interior length of breast and the exterior length of breast on the basis of fitting test. Thereby, 75B$.$80A$.$80B$.$85A$.$85B's the interior lengths of breast were enlarged to 0.7cm, the rest size was enlarged to 0.5cm and the exterior length of breast was enlarged to 0.5cm regardless of sizes. 3. The upper foundation basic patterns of 75AA and 75B were presented and and the basic brassiere pattern and grading pattern were presented through to.

• 복식
• /
• 제25권
• /
• pp.5-20
• /
• 1995

The fashion of late Yi dynasty had explored a possibility of new fashional beauty from its own experiences throughout the history of Korean fashion excluding any interference of foreign fashions, and brought out some characteristics ; first, the aesthetical value focused on the more human fashion resulted in the exposure of waist. This aesthetical change in the fashion of late Yi dynasty produced out results as follows ; the length and width of jacket became short and narrow maintaining the basic form, while the width of skirt became increased to be contrasted exceptionally with the upper coat. This mode of fashion reveals the transitional movement from the emphasis on balance to that on unbalance in the late period of Yi dynasty. But regarding the fact that the proportional change by the ways of putting on skirt became to be similar to the golden ratio, we can see many examples throughout the folk paintings by Shin Yun bok, we find that the fashional beauty of that age pursued ideal harmony and unity all the time being in spite of its tendency toward non-refinement. Second, we see another peculiarity in the mode of woman's fashion from the paintings by Shin Yun-bok who always depicted the hu-man nature frankly. For example, the jacket became shorter to emphasize lady's slim waist, and underwears began to be exposed after the upper part of skirt had been to expose lady's waist while the bottom line pulled up highter than before. Thus, as the function of robe had changed from a mere means of covering into an expression of beauty, the fashion of late Yi dynasty began to express a perfectly new beauty possessing an erotic mood and sensu-ality of a woman, which was its inner aesthetic need. Third, this emergence of new fashional beauty made the mental value of man and the aesthetic views of that time quite different from the previous ones, and finally there came various expressions of a new beauty. There-fore, the woman's fashion of late Yi dynasty is noted for the exposure and emphasis on the body line of a woman after the aesthetic view-point had changed of time toward pragmatism and humanism, while upholding the traditions of Korean clothes and pride for the nation. And our ancestors realized very Korean fashional beauty by pursuing the expressional ways of gentle, indirect emphasis upon the feminine and natural beauty to exclude and ar-tificial, direct and straightforward exposures and images.

• 한국생활과학회지
• /
• 제9권4호
• /
• pp.471-482
• /
• 2000

The purpose of this study is to produce slacks pattern for pregnant women in the mid or second half period of their pregnancy according to the development figure of the body shell from a follow-up measurement. We here would like to produce slacks pattern for pregnant women constructed to fit better with their individual property in their figure and to help maintain the shape and beauty of the lower half of body and would compare it with two manufactured slacks pattern. The results of the study were as follows; 1. As the pregnancy proceeds, the height of natural-waist line went up spontaneously due to the projection of abdominal region, therefore, it was given darts at the front zipper part so that they could maintain a nice figure and to avoid possibility of feeling oppressed. To acquire a slimmer outfit, we made of the slacks-bottom narrower than the width at the knee line, and it worked out. 2. Sensory evaluation for appearance: According to the statistical of the result of 19items on the questionaire, all items showed significant difference(a$\leq$0.01) between the new and A(bunka) B(Kim's pattern) method slacks pattern, with the new pattern having higher scores. The new drafting method proved to be better fitted, to fit the shape of bodies properly and to get a visual effect to look slim.

• 한국구조물진단유지관리공학회 논문집
• /
• 제21권5호
• /
• pp.101-107
• /
• 2017

터널공사의 발파공법의 특성상 여굴 발생은 필연적이라고 할 수 있다. 국내 터널 여굴 관련 설계기준에 의하면 공동구 바닥부의 여굴처리는 채움 10 cm로 되어 있으나 설계 여굴량 이상의 깊이를 모두 콘크리트로 채우게 되면 공사비가 크게 증가한다. 철도터널은 항구적인 콘크리트 궤도를 적용 중에 있다. 그러나 철도터널에서 바닥 여굴이 발생할 경우 압축강도 18 MPa의 콘크리트 채움 시공(T=100 mm)을 하고 있고, 상부에 150 mm ~ 237 mm의 보조도상 콘크리트층, 240 mm 콘크리트 궤도(TCL층)를 시공하는 등의 레일 하부와 터널 암반 사이에 약 600 mm 두께의 콘크리트로 시공하고 있어 경제성이 매우 떨어지는 실정이다. 이 연구에서는 기존터널단면과 변경터널단면에 대해 각각 여굴 깊이에 따라 콘크리트 균열 수치해석 및 콘크리트 균열 위험도 분석, 콘크리트 균열 안정성 확보를 위한 터널 바닥콘크리트 소요 두께에 대한 적정성을 평가하였다.

• 한국수산과학회지
• /
• 제27권1호
• /
• pp.47-58
• /
• 1994

Field observation and numerical experiments with a two-dimensional depth-integrated model were undertaken in order to investigate some of the effects on the flow structure resulting from the construction of a bridge connecting Kohung Peninsula and the Narodo Islands on the southern coast of Korea. Tidal currents passing through the straits between the Narodo Islands showed that, although the phase lagged one hour behind that passing through the strait between Kohung Peninsula and Naenarodo Island, it still kept strong flows of more than 80cm/sec near the bottom. The seawater temperature and salinity within the study area seemed to be higher southward but uniform vertically. The results of the drogue experiments in the straits between the Narodo Islands showed that the drogues moved northward of Sayangdo in the early part of the flood tide, but southward in the late part of the flood tide and finally stopped a mile from the east coast of Surakdo. On the other hand, the numerical computation showed that the flow structures after construction of the bridge piers were basically in line with those before construction of the bridge piers, except for the slight variations of velocities in the vicinity of the bridge piers. A large scale clockwise circulation has been confirmed in the south area of Namsungri of Kohung Peninsula from the computational results of tide-induced residual currents. Referring to these computational results, the impact category on the flow structures due to the bridge piers construction has been estimated to be within around 2km. The results were in good agreement with the field observations.

• 한국수소및신에너지학회논문집
• /
• 제34권4호
• /
• pp.350-357
• /
• 2023

In this study, the experimental investigation and theoretical analysis were conducted to verify the cooling capacity of the cryocooler used for pre-cooling of hydrogen gas. The effect of the flow rate on a copper pipe attached to the bottom of the cryocooler, which has a coil shape in a hydrogen line, was investigated. Temperature sensors were strategically placed at various positions on the cryocooler to analyze the temperature variations with respect to the flow rate. In this study, the thermal properties of hydrogen for the pressure and temperature were utilized using REFPROP to analyze the cooling capacity of the cryocooler. Based on the experimental results derived from this study, the cooling capacity of the cryocooler for pre-cooling hydrogen gas was considered by calculating the cooling temperature according to the flow rate through theoretical analysis.

• 한국해양학회지
• /
• 제23권1호
• /
• pp.24-40
• /
• 1988

해양연구소는 1983년에 한국 망간 노듈개발지역으로 선정된 태평양 북동 척도대의 크라리온-크리퍼톤 균열대사이에서 망간 노듈시료, 코아퇴적물시료를 비롯하여 3.5kHz음파탐사, 에어-건 음파탐사 그리고 지자기탐사등을 설시하였다. 에어-건 음파탐사기록에 의하면, 이 지역에서의 퇴적층은 이 지역내의 DSDP 163 지역 시추결과와 대비될 수 있는 2 내지 3의 층단위로 나뉠수 있다. 최상부 층단위 (Unit I)는 음파특성상 투명하며 후 올리고세에서 중기 에오세까지의 지올라이트 크레이와 방산충 연니로 이루어져 있다. 층단위 IIA는 음파총리가 확연하지만 하부로 갈수록 투명해지고 퇴적물은 팔레오세부터 초기 에오세까지의 방산충 연니로 이루어져 있으며 처어트층과 지올라이트 크레이가 협재되어 있다. 층단위 IIB는 음파 기저면 (해양 현무암) 위에서 음파총리가 뚜렷하고 고화된 백악기의 프린트-처어트질 Nannofossil백악으로 이루어 져있다. 층 단위 I과 IIB는 Line Islands 층군을 이루고 층군 IIB는 명명되어 있지 않다. 전체의 퇴적층과 층단위 I은 Line Islands Ridge 근처를 제외하고는 북쪽으로 갈수록 점차 얇아지는데, 이는 신생대 동안 척도대 CCD의 변화와 태평양판이 북쪽으로 이동하였기 때문이다. 판이 퇴적율이 높은 적도대를 가로질러 이동하는 동안 판이 침강함에 따른 CCD의 변화는 DSDP 시추공 163 퇴적물의 성분이 퇴적시대에 따라 변하도록 하는 요인이 되었다. 후백 악기의 퇴적층(층단위 IIB)는 적도 남쪽 CCD상부 깊이에서 형성 되었고, 층단위 IIA는 팔레오신동안 태평양 판이 CCD 깊이보다 더 깊은 심도로 급격히 침강한 결과이며 단지 서경 149도 서쪽에서만 나타난다. 층단위 IIA와 I은 판이 에오신초기부터 각각 척도지역을 통과하는 동안 또는 통과후에 형성되었다. 한국 망간노듈 개발지의 남쪽에서는 층단위 I이 크리퍼톤 균열대에 의해 동쪽으로 흐르도록 조절되는 남극 저층수의 한 지류에 의해 재분포되어 있는데 이 저총수의 활동은 지질시대의 상당 기간(최소한 에오세중기부터) 동안 작용하였다. 또한 Hawaiian Ridge에서 크라리온 균열대에 이르는 약 350Km에 달하는 거리에 터어바다이트층이 나타나는데, 이 층은 Hawaiian Ridge에서 직접 발생한 저탁류에 의한 것이다.

• 인지과학
• /
• 제13권2호
• /
• pp.1-13
• /
• 2002

본 논문에서는 표층 언어 표현의 응집성 (coherence)이 과학 텍스트의 이해에 어떤 효과를 주는지에 대해 검토하였다 이 연구는 응집성의 강도가 과학 텍스트 이해의 정도와 관계가 있는 지 검토하고. 텍스트의 이해가 지엽적 응집성과 총체적 응집성의 관점으로 어떻게 설명될 수 있는지, 또는 다른 요인과 어떠한 관계가 있는지 조사하였다. 이해에 대한 응집성 강도의 효과를 알아보기 위하여 원인, 반복, 직시사 (deixis). 정박 (anchoring)등의 응집장치 (cohesive devices)를 이용하여 텍스트의 응집성 강도를 조작하였으며. 이에 대한 오프라인 처리 과제를 실시하였다 실험 결과, 응집성이 강한 텍스트가 보다 용이하게 이해된 것으로 나타났다 단락별로 분석된 회상 및 재인 검사의 결과에서는 응집장치의 종류에 따른 응집성 효과가 선택적으로 나타났다 이는 응집장치의 지엽적 효과가 일관적이지 않다는 것을 의미하는 것으로 보인다. 한편 텍스트의 주제가 얼마나 긴밀하게 연결되었는지 분석한 결과. 주제 연결 (topic continuity)의 긴밀성 정도가 텍스트 이해와 관련되어 있음을 발견하게 되었다 이러한 결과는 텍스트 이해가 지엽적 응집성의 선택적 효과에 의해 구축되는 상향적 (bottom-up) 과정뿐만 아니라. 텍스트 전체를 지배하는 하향적 (top-down) 과정에 의해 촉진됨을 암시한다