• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.79-84
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• 2015

A BC-B type bulk carrier is rarely built, so the structural characteristics is not reported and familiar so far. The biggest difference between BC-B and BC-A type vessel is applying alternate cargo loading, which density is over $1.0ton/m^3$. In this paper, 150K DWT class BC-B type bulk carrier is calculated and compared with BC-A type vessel, which has same condition such as main dimension and deadweight, about prescriptive rule and FEA based on CSR. And aspect ratio of target vessel is smaller than typical capsize bulk carrier, so 150K and 180K bulk carrier, which applied BC-A type, are also compared to find feature of wide beam vessel.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.1-10
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• 2003

A computer simulation was carried out to determinate the optimum capacity of bulk type trailer which is used as a tractor attachment. Soil physical properties. such as soil moisture content. bulk density, soil hardness and soil texture were measured in the 10 major rice production area for computer simulation. Mathematical model which include soil physical properties and vehicle factor was used for computer simulation. Most of the soil texture of the investigated area was silty loam. Soil moisture content ranged between 30 and 40% mostly. Soil bulk density was in the range of 1.500 to 1.700 kg/㎥. Soil hardness ranged between 1 to 18 kg/$\textrm{cm}^2$. Soil hardness incorporate the effects of many soil physical properties such as moisture content texture and bulk density, and so the range of soil hardness was greater than any other physical properties. The capacity of bulk type trailer was above 3000 kg$_{f}$ fer the most of the investigated area. and mostly in the range of 4000 to 6000 kg$_{f}$ depending upon the slip. But for the soft soil area such as Andong and Namyang. tractor itself had mobility problem and showed minus trailer capacity for some places. For this area. the capacity of bulk type trailer ranged between 1000 and 2000 kg$_{f}$ mostly so bulk type trailer should be designed as a small capacity compared to the other area.ared to the other area. area.

• Journal of Biosystems Engineering
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• v.28 no.4
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• pp.315-324
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• 2003

If an optimum design technique is applied in the design of packaging container for bulk-type products, merits on the side of not only economic and compression performance but distribution efficiency are expected. Accordingly, minimum board area (mRBA), compression strength (CS) and compression strength per unit area (mCSPA) are important design parameters in optimum design of packaging container for bulk-type products. In this study, mathematical models for mRBA, CS and mCSPA of container as algorithm for optimum design program were developed. In order to develop these models, compression test by various dimensions of container and response surface analysis for mRBA, CS, and mCSPA of container were carried out. In the developed models, volume, W/L ratio and depth of container were principal independent variables. On the found of these models, optimum design program having faculties of outward and inward optimum design and information design was developed. Though the packaging specifications are same, required board area, board combination and cost of the corrugated board required container manufacture were greatly different by boundary conditions in outward design. Moreover, about 6.3∼10.1% in weight of container was lighter, and about 13.2∼25.6% in cost of container was reduced when the program was applied for 2 kinds of bulk-type products.

• Tribology and Lubricants
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• v.23 no.2
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• pp.43-48
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• 2007

Leakage reduction through annular type labyrinth seals of steam turbine is necessary for enhancing their efficiency. In this study, modified geometry of the original combination-type-staggered-labyrinth seal has been suggested and numerical analysis for leakage prediction has been carried out for the modified-combination-type-staggered-labyrinth seal both based on bulk-flow model and using the CFD code FLUENT. The theoretical analysis based on bulk-flow model yields leakage reduction of the modified combination type staggered labyrinth seal by about 11%. Comparing with the result of Bulk-flow model analysis, the leakage result of CFD analysis shows reasonable agreement within 9.8% error.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.1
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• pp.73-80
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• 1988

This study was performed to obtain the basic data which can be applied to use of foaming mortars. The results obtained were Summarized as follows; 1.At the mixing ratio of 1:1, the highest bulk densities were showed by foaming mortars, respectively. But, it gradually was decreased in poorer mixing ratio and more addition of foaming agent. The decreasing rates of bulk densities were increased in richer mixing ratio and more addition of foaming agent. 2.The bulk densities were decreased up to 38.8-55.9% by mix-foaming type and 9.7-23.6% by pre-foamed type than cement mortar. 3.At the mixing ratio of 1:1, the lowest absorption rates were showed by foaming mortars, respectively. But, it gradually was increased in poorer mixing ratio and more addition of foaming agent. The increasing rates of absorption rates were increased in richer mixing ratio and more addition of foaming agent. 4.Absorption rates when immersed in 72hours were showed up tp 3.41-5.85 times by mix-foaming type and 1.05- 1.S5times by pre -foamed type than cement mortar, it was significantly higher at the early stage of immersed time than cement mortar. 5.The correlations between bulk density and absorption rate were highly singnificant, respectively. The multiple regression equations of bulk density and absorption rate were computed depending on a fuction of mixing ratio and addition of foaming agent. it was highly significant respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.170-173
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• 2003

In this paper, we proposed a new bulk LDMOS structure which can be used for RF application, and its fabrication steps were introduced. The simulated devices consist of three types: Bulk device, SLB(SOI Like Bulk), and SOI device. As a result of process and device simulation, we showed electrical characteristics, such as threshold voltage, subthreshold slope, DIBL(Drain Induced Barrier Lowering), off-state current, and breakdown voltage. In this simulation study, the lattice temperature model was adopted to see the device characteristics with lattice temperature during the operation. SLB device structure showed the best breakdown characteristics among the other structures. The breakdown voltage of SLB structure is about 9V, that of bulk is 7V, and that of SOI is 8V.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.2
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• pp.107-115
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• 2009

Lately, the length of tunnel, the number of large-long tunnel over three lanes are steeply increased because of the request for high speed and straight road. Therefore, the maximization of excavation efficiency is needed in tunnel construction. Bulk Emulsion explosives charging system is the spearhead equipment using the radio remote control $&$ mechanization system compare with a traditional method Cartridge type. This study introduced the bulk emulsion explosives which is new method in tunnel blasting and verified the efficiency of bulk emulsion explosives for long-large tunnel. And we tried to compare Cartridge type efficiency with bulk emulsion explosives efficiency by the field test.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.12
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• pp.17-23
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• 2010

In this paper, a new analytical model for deriving the threshold voltage of a short-channel bulk-type MOSFET is suggested. Using the Fourier coefficient method, the Laplace equation in the oxide region and the Poisson equation in the depleted silicon region have been solved two-dimensionally. Making use of them, the minimum surface potential is derived to describe the threshold voltage. Simulation results show good agreement with the dependencies of the threshold voltage on the various device parameters and applied bias voltages.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.138-143
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• 2008

Recently, a new periodic cellular metal(PCM) named as Wire wove Bulk Kagome(WBK) was introduced. Based on the shape of tetrahedra composing a WBK, WBKs are classified into two types, namely, concave and convex type. They are easily differentiated by changing the assembling sequence. The effect of geometrical parameters such as the wire diameter, strut length and number of layers on the compressive behavior of concave type WBK has already been investigated. In this work, the similar works were performed with the convex type WBKs. It was shown that the compressive strength of the convex type WBK was quite similar to that of the concave type. The compressive strengths of convex type specimens also depend on the slenderness ratio, but a little different from those of concave type specimens in the detailed behavior. And densification occurs earlier than the concave type WBK.

• Journal of Biosystems Engineering
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• v.13 no.2
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• pp.51-62
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• 1988

Bulk-type dryers which are widely used for drying special agricultural products such as tobaco leaf, red pepper, mushroom, ginseng, medicinal herb, etc, began to be distributed on a full scale since 1980 and the total number of dryers introduced to farms reached to about 36,600 units as of the end of 1986. In this study a survery was carried on the farmers cultivating special crops, dryer manufacturers and related administrative institutes and associations by means of on-the-spot investigation, mail or interview to collect data on scales and patterns of farming, utilization of bulk-type dryers, production and price streams of the special crops etc. Based on the analysis of the data surveyed predictions were made for the total demand on the bulk-type dryers and for annual demand over five-year span.