• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.3A
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• pp.180-187
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• 2002

The decoding method using covering polynomials is an extended form of error-trapping decoding, and is a simple and effective means to implement decoders for cyclic codes. Covering polynomials can be used for soft-decision decoding as well as for decoding beyond the bounded distance of the code. The implementation complexity is proportional to the number of covering polynomials employed. In this paper, the soft-decision decoding procedure using covering polynomials is described, and the procedure is applied to the [23,12] Golay code. A new set of covering polynomials is derived for the procedure, which is presented as a generalized closed-form solution. The set can be efficiently utilized for decoding a class of cyclic codes including the Golay code. Computer simulation of the described procedure is performed to show the trade-offs between the decoder performance and complexity. It is demonstrated that soft-decision decoding of the Golay code using the derived set of covering polynomials has less than 0.2dB deviation from the optimal performance of maximum-likelihood decoding, with a reduced complexity when compared to the Chase Algorithm 2 combined with hard-decision decoding that has nearly identical performance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.3
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• pp.784-793
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• 2012

This paper deals with subcarrier allocation strategies for soft hand-over in OFDMA-based cellular systems. Two possible subcarrier allocation methods are considered for soft hand-over. One method is to use an identical subcarrier set between the two cells participating in the hand-over. The other is to use different subcarrier sets between the two cells. As expected, the different subcarrier strategy is better in terms of diversity order and BER than the identical subcarrier strategy. It will be shown that the BER performance difference between the two strategies is more noticeable with contiguous subcarrier allocation. But the different subcarrier strategy consumes twice more frequency resources than the other, and there is a trade-off between the two strategies in terms of BER and frequency resources. By considering the trade-off, we also propose a subcarrier allocation strategy for soft hand-over.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.9
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• pp.1596-1612
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• 2011

Coordinated Multi-Point (CoMP) transmission / reception is being studied in Long Term Evolution-Advanced (LTE-A) for future evolution of the $3^{rd}$ Generation Partnership Project (3GPP) LTE. Support of soft handover is essential for improving the performance of cell edge users. CoMP provides a natural framework for enabling soft handover in the LTE system. This paper evaluates the soft handover gain in LTE-A downlink. Mathematical analysis of signal to interference plus noise ratio (SINR) gain and the handover margins for soft handover and hard handover are derived. CoMP system model is developed and an inter-cell and intra-cell interference model is derived, taking into account the pathloss, shadowing, cell loading, and traffic activity. Reference signal received power (RSRP) is used to define the triggers and the measurements for soft handover. Our results indicate that parameter choices such as handover margin and the CoMP set size impact CoMP performance gain.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.4106-4106
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• 2001

A method to discriminate human gallstones by nea. infrared(NIR) spectrometry using a soft independent modeling of class analogy (SIMCA) has been studied. The fifty NIR spectra of gallstones in the wavenumber range from 4500 to 10,000 cm$\^$-1/ were measured. The forty samples were classified to three classes, cholesterol stone, calcium bilirubinate stone and calcium carbonate stone according to the contents of major components in each gallstone. The training set which contained objects of the different known class was constructed using forty NIR spectra and the test set was made with ten different gallstone spectra. The number of important principal components(PCs) to describe the class was determined by cross validation in order to improve the decision criterion of the SIMCA for the training set. The score plots of the class training set whose objects belong to the other classes were inspected. The critical distance of each class was computed using both the Euclidean distance and the Mahalanobis distance at a proper level of significance(${\alpha}$). Two methods were compared with respect to classification and their robustness towards the number of PCs selected to describe different classes.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.10a
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• pp.103-109
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• 2001

Soft sensor is an effective method to deal with the estimation of variables, which are difficult to measure because of the reasons of economy or technology. Fuzzy logic system can be used to develop the soft sensor model by infinite rules, but the fuzzy dividing of variable sets is a key problem to achieve an accurate fuzzy logic model, In this paper, we proposed a new method to develop soft sensor model based on fuzzy neural network. First, using a novel method to divide the variable fuzzy sets by the process input and output data. Second, developing the fuzzy logic model based on that fuzzy set dividing. After that, expressing the fuzzy system with a fuzzy neural network and getting the initial soft sensor model based FNN. Last, adjusting the relative parameters of soft sensor model by the BP learning method. The effectiveness of the method proposed and the preferable generalization ability of soft sensor model built are demonstrated by the simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3768-3774
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• 2009

This paper explored how soft information and hard information were used when SBC(Small Business Corporation, Korea) reviewed government loan applications. The data set is made up of financial and non-financial data of small-business firms since 2004. A non-financial data set is considered as soft information. Relative importance of three kinds information such as credit information, soft information, financial information is compared with each other by using the logit model. As a result, credit information is most critical to the loan approval, and then soft information follows, lastly financial information has the smallest effect on the loan approval. This is because the credit information is made up of the non-linear combination of soft information and financial information. When the relative importance of soft information and financial information is considered, soft information is relatively more critical to the loan approval then financial information. This is because financial ratios provided by small-business firms are not reliable enough.

• Journal of the Korean Operations Research and Management Science Society
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• v.25 no.2
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• pp.77-86
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• 2000

Consumers facing a large number of brands to choose from are known to use simplified heuristic to screen a set of relevant brands called the consideration set from the whole alternatives, Purchase decisions are then made from the brands in the consideration set, Two approaches have been suggested to model the two-stage choice process., One is to treat the con-sideration set as a crisp set (e.g Roberts and Lattin 1991) The other is to treat the set as a fuzzy set (e.g. Fortheringham 1988) The paper empirically compares the two types of models using data for soft drinks sneakers and departments. The results show that a model employing the crisp set approach fits the data better than that with the fuzzy set approach and better than a single-stage choice logit model.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.6
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• pp.1154-1162
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• 2020

In this study, the soft textile actuator is produced for a smart wearable with the shape memory effects from linear shape memory alloys of Nickel and Titanium using the driving force through the fabrication process. The measurement model was designed to measure dynamic characteristics. The heating method, and memory shape of the linear shape memory alloy were set to measure the operating temperature. A shape memory alloy at 40.13℃, was used to heat the alloy with a power supply for the selective operation and rapid reaction speed. The required amount of current was obtained by calculating the amount of heat and (considering the prevention of overheating) set to 1.3 A. The fabrication process produced a soft textile actuator using a stitching technique for linear shape memory alloys at 0.5 mm intervals in the general fabric. The dynamic characteristics of linear shape memory alloys and actuators were measured and compared. For manufactured soft textile actuators, up to 0.8 N, twice the force of the single linear shape memory alloy, 0.38 N, and the response time was measured at 50 s.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.191-196
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• 2007

With the development of micro electronic circuits and optical equipment, the demand for developing smart munitions with the ability to autonomously search for and attack targets has increased. Since the electronic components within smart munitions are affected by high temperatures, pressure, and impulsive forces upon the combustion of gunpowder, stability and reliability need to be secured for them. Securing those stability and reliability requires soft recovery system which can decelerate smart munitions. A theoretical analysis of flow is performed for the secure recovery of bullets on the basis of Navier-Stokes equation for compressible fluids. The inner pressure on a pressure tube, the speeds of bullets, and the deceleration of munitions are calculated theoretically. Theoretical results are compared with the data from the experiment with soft recovery system set up at the laboratory.

• Journal of the Korea Society for Simulation
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• v.7 no.2
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• pp.153-165
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• 1998

In the Is-95 soft handoff scheme of CDMA, there occurs a tradeoff between improving quality due to the space diversity and additional resource management like updates of the active set during soft handoffs. In addition, if a mobile terminal is alternating two adjacent cells, a well-known phenomenon called ping-ping causes the resource management to be seriously degraded. By noting that in general the probability that a user initiates additional handoffs is exponentially decreased as the user has already handed over one or more times, we present a soft handoff algorithm making use of handoff profiles of mobile terminals to improve resource utilization. In the proposed algorithm the number of handoffs made so far during the call is recorded in the mobile profile and the profile data is used for adjusting handoff parameters such as the value of add or drop threshold (T_ADD or T_DROP). Through simulations, the result of the proposed algorithm is shown to improve the handoff performance by lowering the number of handoffs while simultaneously reducing resource waste.