• 지질공학
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• 제19권3호
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• pp.345-350
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• 2009

경주-감포간 국도건설공사 중 양북터널의 종점부측은 산악지형으로 도로가 산지의 사면으로 통과하기 때문에 대절토 구간으로 이루어져 있다. 이 구간에 사면안정공법으로 PAP옹벽을 설치하였다. 옹벽을 설치한 후 6개월 정도가 지나면서부터 PAP옹벽의 앵커체 일부가 파단되었다. 즉시 계측기를 추가 배치하고 응급조치를 한 다음 지금까지의 계측기록으로 역해석을 실시하였다. 동시에 앵커체의 정착부를 확인하기 위한 지층조사와 앵커체의 이상여부를 확인하는 인장시험을 실시하였다. 역해석 결과 당초 설계에 적용한 토질정수의 90%를 적용함이 타당한 것으로 나타났다. 이를 근거로 재설계를 시행하였으며, 재설계의 결과는 당초 허용응력 306 kN이던 앵커체를 591 kN 및 784 kN의 앵커체로 교체하고, 정착부의 위치를 당초 11.0 m에서 23.0 m를 증가시켰다. 앵커체를 교체한 후 약 5개월 정도가 지난 지금까지의 계측 결과는 안정된 상태를 보여주고 있다. 이 사례는 대형사고로 이어질 수 있었던 사례를 신속하고 정확한 조치로 사면을 안정화시킨 사례이다.

• 한국정밀공학회지
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• 제21권1호
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• pp.149-158
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• 2004

In most RP processes, the inherent stair-stepped surfaces and shrinkage-induced warping of the parts require post processing such as surface finishing. To minimize such defects, VLH-ST, a newly developed RP process, employs a 3.9-mm thick expandable polystyrene (EPS) foam sheet and a hot wire to contour it to have slant linear-interpolated sides. The use of relatively thick sheets for layers, however, limits the process capability of constructing fine details, especially smaller than the layer thickness. This study is focused on the development of a post processing method fo fine details of VLM-ST parts. The post-processing tool was designed to meet all the requirements for the desirable post processing. It adopted a hot wire as a means of melting the EPS foam sheet. Various basic experiments on the post processing were carried out to obtain the optimal process conditions. The dominant process parameters such as the radiated heat input, the tool speed, and the gap between the tool tip and the foam sheet (tool height) were considered in the experiments. The effectiveness of the developed post-processing method fo forming or engraving fine details on the VLM-ST parts has been thus demonstrated. The experiments on engraving several sets of letters, such as CANESM, 인간, and 한국과학기술원, on the EPS foam sheet were carried out. In addition, a flowery shape was engraved on a three-dimensionally curved surface of a pottery-shape VLM-ST part.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1507-1510
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• 2005

This study was carried out as a part of the research on the development of a maskless and electroless process for fabricating metal micro/nanostructures by using a nanoindenter and an electroless deposition technique. $2-\mu{m}-deep$ indentation tests on Ni and Cu samples were performed. The elastic recovery of the Ni and Cu was 9.30% and 9.53% of the maximum penetration depth, respectively. The hardness and the elastic modulus were 1.56 GPa and 120 GPa for Ni and 1.49 GPa and 100 GPa for Cu. The effect of single-point diamond machining conditions such as the Berkovich tip orientation (0, 45, and $90^{\circ}$) and the normal load (0.1, 0.3, 0.5, 1, 3, and 5 mN), on both the deformation behavior and the morphology of cutting traces (such as width and depth) was investigated by constant-load scratch tests. The tip orientation had a significant influence on the coefficient of friction, which varied from 0.52-0.66 for Ni and from 0.46-0.61 for Cu. The crisscross-pattern sample showed that the tip orientation strongly affects the surface quality of the machined area during scratching. A selective deposition of Cu at the pit-like defect on a p-type Si(111) surface was also investigated. Preferential deposition of the Cu occurred at the surface defect sites of silicon wafers, indicating that those defect sites act as active sites for the deposition reaction. The shape of the Cu-deposited area was almost the same as that of the residual stress field.

• 대한기계학회논문집
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• 제17권8호
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• pp.2001-2011
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• 1993

This study deals with the machining of sculptured surfaces on 5-axis CNC milling machine with end mill cutter. The study (I) has the following contents. In 5-axis CNC milling, CL-data consist of CC-data and cutter axis direction vector at the CC-point. Thus, in machining of the sculptured surface on 5-axis CNC milling machine, determination of the direction vector of the milling cutter is very important. The direction vector is obtained by the fact that bottom plane of the milling cutter must not interfere with the free-form surface being machined. The interference is checked by the z-map method which can be applied in all geometric types of the sculptured surfaces. After generating NC part programs from 5-axis post-processing algorithms, sculptured surfaces were machined with 5-axis CNC milling machine (CINCINNATI MILACRON, 20V-80). From these machining tests, it was shown that the machining of the free-form surfaces on 5-axis CNC milling machine with the end mill has smaller cusp heights and shorter cutting time than on 3-axis CNC milling machine with the ball-end mill. Thus, 5-axis CNC end milling was effective machining method for sculptured surfaces. The study (II) deals with the prediction of cusp height and the determination of tool path interval for the 5-axis machining of sculptured surfaces on the basis of study(I).

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.1101-1107
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• 2005

Mold industry has the difficulty to employ young people as the successors of the skilled workers, because it has been regarded as a 3D-jobs(dirty, difficult, and dangerous). To overcome this situation, thus, manufacturing technologies maintained in the factory should be systemized, and engineering systems should support unskilled workers to do their jobs without any difficulty. As a research of developing the supporting system, this study proposes a decision support system that facilitates unskilled workers to easily select high quality NC-data, as well as to increase productivity. The proposed system is assumed to follow a CAM operation scenario that consists of next three steps: 1) identifying several process plans and enumerating feasible unit machining operations (UMOs) from material and part surface information, 2) creating all feasible NC-data based on UMOs using a commercial CAM system, 3) selecting the best NC data among the feasible NC data using four screening criteria, such as machining accuracy, machining allowance, cutting load, and processing time. A case study on the machining of a camera core mold is provided to demonstrate the proposed system.

• 한국농공학회지
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• 제8권2호
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• pp.1124-1140
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• 1966

'This hydraulic experiment have been practised Juk an Reservoir spillway and discharge 'channel which the province Kyong Buk was constructed and designed U. hook, for seizing all state of hydraulic. As result of the experimellt planning and making the model test, it has gained the necessary data at the amendment, projection of the most rational and economical result. 1. Project (1) Experiment project....1/30 of the discharge (2) project flood....0.01945 $m^3$/sec (rapidly) 2. Design Experiment It were sighted the water level for the nine point (L. & R. sides of No. O, L. & R. of No.1, L. side of NO.2, NO.3, No. 4 and NO.5), but it appeared each other that the lowest water level was 0.63 m at spillway (No.5) and the highest water level 0.735m less than planning water level O.75 m at No. 0. It was regarded as the phenomena appearing the difference from the calculation of the rational formular and coefficient of discharge. 3. Experiment examine E. ${\circled1}$ As a table (2) it had not a difference in comparision with design and was some lower value than design experiment's. E ..${\circled2}$) !twas same table (3) in a consequence of Experiment contracted Rocky cutting. E.${\circled3}$. ${\circled4}$ It was done amend.ment Experiment by elevating G.H. in only control point, but was not sure result as a table (2)(3)(4), and so it was changed largely in ${\circled5}$ Experiment. E. ${\circled5}$ Increasing water level was understanded to be proportion to $V^2$ in consideration of centrifugal force in the curve part and showed velocity contracting in curve the effect order's being regular in consequence of 1/6 sloped extending G.H. attached from 5 No. 0 to 1. 50 m, to S No. 0+5m. (S; discharge channel number).

• 한국실내디자인학회논문집
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• 제19권6호
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• pp.91-99
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• 2010

There is a commonality between Frank Lloyd Wright and Charles Rennie Mackintosh in that they created the new patterns of geometric Art Nouveau from the late 19th and early 20th centuries. This study compares the furniture of Wright and Mackintosh who had significant impacts on the development of modern design for each of the periods divided by their design feature to find the individualities and similarities of their design. It is an analytical approach with an accurate understanding of the design trends of the Art Nouveau era. The results of the furniture comparison are as follows: The finding is that Wright and Mackintosh designed creative furniture in harmony with a specific indoor space, Organic design was well expressed through the selection and use of wooden materials, Based on the understanding of tree characteristics, they did not use detailed decorations, but designed the simple and rigorous forms of furniture with highlighted interest in geometry. As for shape, Wright's furniture in his early days tend to be look largely formal and heavy. Since his debut in Japan in 1905, the furniture design became very sophisticated. On the other hand, Mackintosh's chairs are characterized by plenty of geometric patterns and long back. In many cases, his chairs were designed as part of formative elements in space, not for the purpose of furniture itself. As for materials and colors, Wright used mainly cherry wood. And he also utilized metals colored in olive green, red-brown and others for office furniture. The frames, fabrics and leather used for most of the furniture have natural colors, which are harmonious with spaces. Meantime, Mackintosh used primarily oak and ash trees. He used seat cushions and various colors to make the design of furniture have a sophisticated and simple image. The materials used for seat panel are horsehair, rush, silk and leather. He applied these materials to the furniture by weaving or cutting them.

• 한국의류산업학회지
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• 제15권6호
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• pp.874-885
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• 2013

This study analyzes the visage in fashion illustration based on the deconstructed visage of Francis Bacon's paintings as well as analyzes fashion illustration works since 2000. The deconstructed visages in Francis Bacon's paintings are classified as blurring, elimination, distortion and division. The expressive methods and meanings in fashion illustration (according to categorization) are as follow. Blurring shows an ambiguous visage organ by the sweeping of the brush, removal of a boundary among the visage, body and clothes, gradation of organic line like visage shapes, stretching of the a plat combined to visage and fragmentation of visage. It represents an uncertainty of the fashion theme and image interpretation, impossibility of figure by ambiguity, fantastic effect and the induction of the uncanny. Elimination shows the background color's painting of a photo-montage, overlap of a cutting of visage's part and background of a plat, elimination of the visage and the elimination of eyes, nose or lips. It represents a weakened identity, the reinforcement of anonymity, creation of a violent image, and uncanny unfamiliarity. Distortion shows a distorted visage by free drawing, and unconscious drawing line, fluid digital body, combination of an unconscious curve, and an eccentric combination of the accidental. It represents the relief of specialty about realistic existence, hypothetical immateriality and fantasy. Division shows overlapped visages with different angles, the weird combination of a plural visage and different species and a plural breakaway of direction, and the position of several organs. It represents motion by power's trace, non-territory of species, ambiguity and uncertainty and the uncanny.

• 자원환경지질
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• 제17권4호
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• pp.273-282
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• 1984

분천 광산의 망간 광상은 선캠브리아기 율리통의 변성암류의 엽상 구조를 횡단하는 $N20^{\circ}E$ 방향의 단층면을 따라 열수 용액이 충진하여 형성된 열수 기원의 규산 망간 광석과 이의 표성 산화작용에 의하여 생성된 산화 망간 광석으로 구성되어 있다. 규산 망간 광석은 주로 파이록스만자이트로 구성되어 있으며 소량의 능망간석, 석영, 녹니석 및 황화황물(황철석, 황동석, 섬아연석, 방연석, 알라반다이트, 자류철석)등이 포함되어 있다. 산화 망간 광석은 엔소타이트, 버네사이트, 토도로카이트, 망가나이트 등으로 구성되어 있다. 파이록스만자이트와 능망간석의 산화과정 및 광물생성 순서는 다음과 같다. 능망간석$_{\rightarrow}^o$토도로카이트$_{\searro}^o$파이록스만자이트$_{\line(10){90}}^o{\nearro}$버네사이트$_{\rightarrow}^o$엔소타이트$_{\rightarrow}^s$ 망간나이트 (o : 산화, s : 단순한 순서) 광석을 구성하고 있는 광물들은 광학적, X선적, 적외선 흡수분광학적, 열분석에 의하여 감정 연구되었다.

• 지질공학
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• 제27권3호
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• pp.345-351
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• 2017

Acid drainage in civil engineering structures such as tunnels may lead to the deposition of precipitates that clog drainage channels and pipework. In evaluating acid drainage, the Fe content of water and precipitates, indicated by reddish brown coloration of rock surfaces, rivers, and soils, may be an important factor. In this study, acid drainage was evaluated by analyzing the Fe content of reddish brown seepage water that occurred in part of a tunnel. Geological investigations around the tunnel revealed a hydrothermal alteration zone cutting the bedrock, and cropping out in the upper parts of the tunnel. Analysis of drillcore revealed many fracture zones and veins. Inductively coupled plasma spectrophotometric analyses of water, precipitates, and soil samples, collected in the seepage water zone and around the tunnel, were conducted to evaluate acid drainage. The Fe content of seepage water in the tunnel was 0.030-0.333 mg/kg, which is 2-22 times higher than in local groundwater. The Fe content of precipitates in the tunnel was 165,403-301,051 mg/kg, similar to the 206,167-422,964 mg/kg content of drillcore from the hydrothermal alteration zone located above the tunnel. It is concluded that the seepage water is derived from Fe-containing acid drainage flowing in perforated tunnel drainpipes along the fracture zones and veins around the hydrothermal alteration zone.