• Journal of Biosystems Engineering
• /
• v.20 no.1
• /
• pp.58-65
• /
• 1995

A numerical study for a two dimensional multi-jet with crossflow of the spent fluid has been carried out. Three different distributions of mass-flow rate at 5 jet exits were assumed to see their effects upon the flow characteristics, especially in the jet-flow region. For each distribution, various Reynolds numbers ranging from laminar to turbulent flows were considered. Calculations drew the following items as conclusion. 1) The development of the free jets issued from downstream jets was hindered by the crossflow formed due to jets. Consequently, the free jet was developed into the channel flow without any evident symptom of impingement jet flow characteristics 2) The crossflow induced the pressure gradient along the cross section of jet exits and the value of the pressure gradient increased as going downstream. The crossflow generated also the turbulent kinetic energy as it collied with the downstream jets. 3) The skin friction coefficient along the impingement plate was affected more by the distribution of mass flow rate at jet exits rather than by the Reynolds number. The skin friction coefficient was inversely proportional to the square root of the Reynolds number, regardless of flow regime when a fully developed flow was formed in the jet flow region. 4) The distribution of the skin friction coefficient along the impingement plate was found to be controlled by adjusting the distribution of mass flow rate at jet exits.

• Journal of Distribution Research
• /
• v.1 no.2
• /
• pp.141-172
• /
• 1996

This study is to investigate global logistics strategies of Korean electronics companies. in terms of service parts. According to the survey, Korean electronics companies were pursuing multi-level global logistics network such as global, continental, national, regional and service center echelon for improving the efficiency of service parts global logistics. Especially there was a tendency of developing new continental distribution centers. And the companies were exploiting efficiency through inventory control by multi-level echelon, demand forecasting by the product life cycle and supply and service lead time management. But there were some insufficient factors for the efficiency of global logistics operation at the construction of worldwide real time logistics information system and pursuit of the efficiency on the whole network including subcontractors. For the future competitive advantage of the Korean electronics companies, the following are suggested: 1) the establishment of arranged logistics channel adjusting each company's global strategy, 2) the construction of worldwide real time logistics information system, 3) the reengineering of all logistics procedures such as order processing, shipping, inventory control, etc., 4) the enhancement of the ratio of the supply from the external companies and the internal manufacturing subsidiaries at each continent, 5) and the pursuit of operational internalization of external subcontractors.

• Proceedings of the KIEE Conference
• /
• 1992.07a
• /
• pp.437-440
• /
• 1992

We design a multi-element photo-detector to measure the size of particles using the diffracted light energy distribution. The light energy that is scattered by particles in the collimated laser beam is collected by the Fourier transform lens and directed to the multi-semicircular concentric annular detecters. The scattered profile measured by the photodetector is sampled by a 32 channel analog-to-digital converter. A nonnegative least squares analysis translates the light energy distribution into the corresponding unique particle size distribution.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.21 no.9
• /
• pp.1198-1206
• /
• 1997

The flow characteristics of an intermittent fuel injection into a stationary ambient air were investigated using gasoline. The measurements were made by two-channel, air cooling type Phase Doppler Anemometer(PDA) system (DANTEC, 750 MW). And a pintle type injector of MPI (Multi-point Port Injection) system was utilized as a fuel injector. The PDA receiver optic was set up in a 60.deg. C forward scatter arrangement to obtain the optimum scattering signal of fuel droplets. The data were obtained by synchronizing PDA system with the fuel injection period, and the axial and radial velocity and turbulent components of fuel droplets were mainly measured for the analysis of temporal and spatial distribution depending upon the fuel injection pressures.

• Korean Management Science Review
• /
• v.11 no.1
• /
• pp.73-90
• /
• 1994

Recently the recongnition of Logistics becomes important to enterpries as a means for improving their competition, but the Korea enterpries falls for far behind in management techniques for analyzing realities and problems in the Logistics compare to the advanced countries. Especially the function of inventory control which is most undeveloped in them should be improved in Korea. Inventory is very important in Logistics, but there exists trade-off between inventory level and customer in the service level. It is difficult to coordinate both the reduction in the inventory level and the enhancement in the service level. Its effective technique is a DRP system. In general, it deals with arborescent distribution network in which a given channel member has a single source of supply. This article aims to present a DRP system, and more a DRP system which is flexible and responsive in the multisourcing, multi-echelon distribution network. Related research issues are discussed. Finally, using a DRP system on logistics and the management performance. So we can help the physical distribution improvement of the Korean enterprises.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.54 no.5
• /
• pp.338-347
• /
• 2005

A computer-based low back muscle evaluation system was designed to simultaneously acquire, process, display, quantify, and correlate electromyographic(EMG) activity with muscle force, and range of motion(ROM) in the lumbar muscle of human. This integrated multi-channel system was designed around notebook PC. Each channel consisted of a time and frequency domain block, and T-F(time-frequency) domain block. The captured data in each channel was used to display and Quantify : raw EMG, histogram, zero crossing, turn, RMS(root mean square), variance, mean, power spectrum, median frequency, mean frequency, wavelet transform, Wigner-Ville distribution, Choi-Williams distribution, and Cohen-Posch distribution. To evaluate the performance of the designed system, the static and dynamic contraction experiments from lumbar(waist) level of human were done. The experiment performed in five subjects, and various parameters were tested and compared. This system could equally well be modified to allow acquisition, processing, and analysis of EMG signals in other studies and applications.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.1258-1260
• /
• 2003

Cloud's properties can be showed on different spectral channel. The 0.65${\mu}$m reflectance is mainly function of cloud optical thickness and reflectance of 1.6${\mu}$m is sensitive to cloud phase and particle size distribution. So we can use multi-spectral information to analysis cloud's microphysical properties.

• Asia Marketing Journal
• /
• v.16 no.2
• /
• pp.15-38
• /
• 2014

This paper explores the influence of pursuing goals on customer channel preference in Chinese rural market. With the rapid change in distribution channels and increase in multi-channels, it is necessary to understand the preference for channel choice as well as product choice. This study empirically validated the conceptual framework of the relationship between the pursuing goals and customer channel choice proposed by Balasubramanian, Raghunathan, and Mahajan (2005). Based on the survey data of 232 fertilizer customers in Chinese rural market, this study explores how economic, social, and psychological pursuing goals can impact customer channel preference by mediating variables of product utility and process utility. The results indicate that pursuing goals positively related with product utility and process utility, and product / process utility can mediate the relationship between pursuing goals and customer channel preference positively. Consequently, we can conclude that customers' economic-social-psychological pursuing goals can directly influence customer channel preference via their purchase process utility and product utility. This result also implies that product utility is effective on process utility during consumer's buying decision making, and process utility and product utility are not mutually independent. Therefore, purchase process utility is a "latent driving force" on customer's channel choice decision.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.161-162
• /
• 2008

In this paper we design an irregular low-density parity-check (LDPC) code for a multi-input multi-output (MIMO) system. The considered MIMO system is minimum mean square error soft-interference cancellation (MMSE-SIC) detector. The MMSE-SIC detector and the LDPC decoder exchange soft information and consist a turbo iterative detection and decoding receiver. Extrinsic information transfer (EXIT) charts are used to obtain the edge degree distribution of the irregular LDPC code which is optimized for the input-output transfer chart of the MMSE-SIC detector. It is shown that the performance of the designed LDPC code is much better than that of conventional LDPC code optimized for the AWGN channel.

• Progress in Medical Physics
• /
• v.3 no.1
• /
• pp.19-24
• /
• 1992

We have desingned multi channel dosimetry system with Intel single-chip microprocessor. We considered that this system is very useful for patient dose measurement, measurement of sealed source dose distribution and calibration of small field for stereotatic radiosurgery system We have designed that this system use commercially available semicondutor detector and personal computer can control this system and process data through RS-232C serial port.