• Journal of Forest and Environmental Science
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• 제24권1호
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• pp.1-14
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• 2008

Clearcutting has been the dominant harvesting method in British Columbia (representing 95% of the total area harvested annually). However forest managers are increasingly recommending the use of alternative silvicultural systems and harvest methods, including various types of partial cutting, to meet ecological and social objectives. In this study we compared harvesting productivity and harvesting costs between treatments through detailed and shift level time studies in 300-350 year-old Interior Cedar-Hemlock stands in British Columbia, Canada. Recommendations for improving operational planning/layout and the implementation of clearcut and partial cutting silvicultural systems were made. Harvesting costs varied in the ground-based clearcut treatments from $10.95/$m^3$ - $15.96/$m^3$ and $16.09/$m^3$ - $16.93/$m^3$ in the group selection treatments. The ground-based group retention treatment had a cost of $13.39/$m^3$, while the cable clearcut had a cost of $15.70/$m^3$. An understanding of the traditional and alternative wood products that could be derived from the harvested timber was imperative to increasing the amount of merchantable volume and reducing the corresponding harvesting costs. Stand damage was greatest in the group selection treatments; however, mechanized felling showed an increase in stand damage over manual felling while grapple skidding showed a decrease in skidding damage compared to line skidding.

• 복식
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• 제56권7호
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• pp.152-166
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• 2006

The purpose of this study was to make patterns for lingerie look after examining expressive characteristics and constructive elements of lingerie look. As underwear became outerwear, position of wearing, materials, and details had changed, and the phenomenon to expose one's body has increased. The constructive elements found in the lingerie look were classified into silhouette, fastening, dart, and cutting line. Many of corset looks revealed cutting lines such as diagonal, perpendicular, and horizon. Brassiere look used perpendicular rutting lines or horizontal cutting lines passing through the bust point in order to highlight the volume by adding darts. There were styles Of chemise looks that used princess lines or separately added a brassier on the breast. Based on the examination of the elements, a total of four apparel works were created, including one flat pattern and three draping patterns. With new infra-apparel designs and patterns, this study was able to artificially highlight the body and express the beauty of costume through revelation of body. In addition, it explored the possibility that the phenomenon that underwear becomes outerwear may be a new idea of dress designing.

• 한국분말재료학회지
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• 제2권2호
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• pp.135-141
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• 1995

As the first step of study on fabrication of ceramic powders from phytoliths in rice, especially in rice husks, pulverization method of rice husks and the properties of milled rice husks were investigated. Impact methods, such as ball milling, were not meaningful for pulverizing elastic and thin fabric structure of rice husks. The most effective one was cutting method. In the present work, a rotating knife cutting method was applied to pulverizing rice husks. A 40-mesh screen was inserted under the rotating knives. The most portion of the milled powder was found in -50/+100 mesh section. Morphology of the milled rice husks revealed that the husks larger than 70 mesh were flake-like shape, at -70/+100 mesh section relatively equi-axed shape, at -170/+325 mesh section rod-like shape, and below 325 mesh section dust-like shape. Tap density of raw rice husks was about 0.1 $g/cm^3$, while those of milled rice husks were over $0.4 g/cm^3$. This meant that, for a given volume of reactor, raw material charge can be increased more that 4 times when using milled rice husks than unmilled one. True densities of unmilled and milled rice husks were higher than $1.4 g/cm^3$, and increased with decreasing milled sizes.

• International Journal of Precision Engineering and Manufacturing
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• 제6권2호
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• pp.46-49
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• 2005

Recently, many research results have been reported about nano-tip using carbon nanotube because of its better sensing ability compared to a conventional silicon tip. However, it is very difficult to identify the carbon nanotube having proper length for nano-tip and to attach it on a conventional tip. In this paper, a new method is proposed to make a nano-tip and to control its length. The electrochemical etching method was used to control the length by cutting the carbon nanotube of arbitrary length and it was possible to monitor the process through current measurement. The etched volume of carbon nanotube was determined by the amount of applied charge. The carbon nanotube was successfully cut and could be used in the nanogripper.

• 조명전기설비학회논문지
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• 제27권1호
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• pp.17-23
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• 2013

The BESS(Battery Energy Storage System) is an useful device for load leveling, but the high cost, installation space and safety issues are the main barriers for supplying it widely. The important factor in supplying BESS to customers successfully is the payback period. As most of the H/W cost factors are uncontrollable, the optimization of storage volume can be useful factor in improving payback period. In order to obtain optimized BESS volume, the load factor, demand ratio, peak shaving ratio, electric rates and benefits from DR participation of customer should be analyzed. In this paper, we could verify the peak cutting capability and cost effectiveness under the some proposed conditions and changing value of PCS and battery based on the customers data after volume optimization process was applied, and we can identified the saturation point of load factor and shortening of customer's payback period.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1619-1625
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• 2016

Recently, as the public interests about the 3D printing technology are increased, various kinds of 3D printers are being released. But, they are limited to use because they cannot fabricate an object which is larger than the printer's printing volume. To relieve this problem, we propose an interactive 3D mesh editing system for 3D printing the object that is larger than the printing volume. The proposed 3D editing system divides the input 3D mesh using the user's line drawings defining cutting planes and it attaches various connectors. The output meshes are guaranteed to fabricate without post-processing. The printed parts can be assembled using the connectors. Our proposed system has an advantage that it can be used easily by non-professional 3D printer users.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1999년도 가을 학술발표논문집 Vol.26 No.2 (2)
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• pp.604-606
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• 1999

본 논문은 3차원 볼륨데이터의 실시간 절단에 관한 연구이다. 3차원 데이터를 가시화하는 방법에는 서피스 렌더링과 볼륨렌더링이 있는데, 서피스 렌더링은 처리시간이 적게 걸리는 장점이 있고, 볼륨 렌더링은 데이터의 내부를 가시화할 수 있는 장점이 있다. 본 논문에서는 위 두 가지 방법의 장점을 이용해서, 시점에 변화를 주면서 3차원 데이터를 절단하여 내부를 실시간으로 가시화 할 수 있는 방법에 관해서 기술한다. 또한 3차원 데이터의 저장 공간을 줄여서 효율적으로 메모리를 사용할 수 있게 하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.871-872
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• 2006

Nowadays the market for diamond tools grows rapidly. The present decline in the price of industrial diamond makes it a commoditised product capable of competing with conventional abrasives. In terms of production volume, the largest group of diamond tools comprises the metal-bonded diamond impregnated tools, such as sawblades, wire saws, and core drills for cutting stone and construction materials, and core bits for mining applications. This article provides a compendious coverage of the powder metallurgy (PM) diamond tool-making routes, and identifies the recent trends towards changing the tool design and composition to render it cheaper and more efficient.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1404-1406
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• 1995

In this paper, argon gas was used for numerical analysis of an arc in a cutting plasma torch driven by constant current. We established nozzle-constricting type torch domain and calculated steady state characteristics of argon arc plasma using the control volume method(CVM). For simplicity, we assumed that the flow field is laminar and the local thermodynamic equilibrium(LTE) prevails in all domain regions. We also neglected cathode-fall and anode-fall effects. Considering magnetic pinch effect and viscosity effect, we solved the momentum equation. Voltage drop in the arc column due to input current was calculated from the temperature field obtained by the energy balance equation.

• 오토저널
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• 제15권3호
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• pp.120-125
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• 1993

The surface roughness of workpiece is reduced during spark-out. The reduction of roughness is a benefit of spark-out, but spark-out lowers productivity. The characteristics of spark-out are different to those of plunge grinding to which feed is applied. This difference is due to overlapping cutting during spark-out. Effect of spark-out is in proportion to volume of grain wear. This phenomenon is due to different overlapping area. Dressing interval can be enlarged by spark-out, when volume of grain wear is large. In this study, the characteristic of spark-out was studied by spark-out obserbation in various grinding conditions. For this purpose thrust force, spark-out time and surface roughness of workpiece were experimentally investigated in various grinding conditions.