• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.1
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• pp.76-84
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• 2007

The goal of this paper is to improve the watermarking performance using the following two methods; watermark estimation and low density parity check (LDPC) codes. For a blind watermark decoding, the power of a host image, which is hundreds times greater than the watermark power, is the main noise source. Therefore, a technique that can reduce the effect of the power of the host image to the detector is required. To this end, we need to estimate watermark from the watermarked image. In this paper, the watermark estimation is done by an adaptive estimation method with the generalized Gaussian distribution modeling of sub-band coefficients in the wavelet domain. Since the watermark capacity as well as the error rate can be improved by adopting optimum decoding principles and error correcting codes (ECC), we employ the LDPC codes for the decoding of the estimated watermark. Also, in LDPC codes, the knowledge about the noise power can improve the error correction capability. Simulation results demonstrate the superior performance of the proposed algorithm comparing to LDPC decoding with other estimation-based watermarking algorithms.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4811-4814
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• 2013

Background: To assess the significance of social factors as risk factors for carcinoma cervix and to determine the significance of blood group to prevalence of carcinoma cervix in a semi-urban population of Kolar, Karnataka, India. Materials and Methods: One hundred cases of carcinoma cervix were included in the study, along with 200 females of the same ages considered as controls. Case details were collected from the hospital record section regarding social factors and blood groups and the data were analyzed by descriptive statistical methods. Results: Blood group B showed the highest number of cases (55 cases) followed by blood group O (29 cases) in carcinoma cervix which was statistically significant (p<0.001). Age of marriage between 11 to 20 years showed highest number of carcinoma cervix cases (77 cases) and this also was statistically significant (p<0.001). Patients with rural background were 75 (p=0.112, odds ratio: 1.54), parity of more than or equal to two constituted 96 cases (p=0.006, odds ratio: 4.07) and Hindu patients were 95 in number (p=0.220, odds ratio: 1.89). Conclusions: Blood group B and age of marriage between 11 and 20 years were significantly associated with carcinoma cervix in our population. Region of residence, parity and religion presented with a altered risk for carcinoma cervix.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2367-2372
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• 2015

One of various low-density parity-check(LDPC) codes that has been adopted in many communication standards due to its error correction ability is a quasi-cyclic LDPC(QC-LDPC) code, which leads to comparable decoder complexity. One of the main blocks in the QC-LCDC code decoder is a multi-size circular shifter(MSCS) that can perform various size rotation. The MSCS can be implemented with many structures, one of which is based on Banes network. The Benes network structure can perform the normal MSCS operation efficiently, but it cannot use the properties coming from specifications like rotation sizes. This paper proposesd a scheme where the Benes network structure can use the rotation size property with the modification of the control signal generation. The proposed scheme is applied to the MSCS of IEEE 802.16e WiMAX QC-LDPC decoder to reduce the number of MUXes and the critical path delay.

• The KIPS Transactions:PartC
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• v.9C no.4
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• pp.589-596
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• 2002

Tn the data transmission service of the mobile host, it is needed to reduce the bandwidth and to make a reliable error recovery. there are two appropriate methods in that. One is FEC which retransmits the parity of error recovery, in case of happening of the loss after forming the parity of error recovery by grouping original data. The other is local recovery based on server which can block the implosion of transmission. The use of FEC and local recovery based on server at the same time enables the reliable multicast. This paper suggests algorithm that recovers the loss by FEC and local recovery based on server through the solution of the problems about triangle routing, tunnel convergence by dividing mobile host into two parts-the sender and the receiver. This model about the loss of algorithm tested the efficiency of performance by the homogeneous independent loss, the heterogeneous independent loss, the shared source link loss model. The suggested algorithm confirms effectiveness in the environment where there are much data and many receivers in mobile host.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2C
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• pp.172-181
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• 2010

In this paper, we propose an adaptive block quantization method. The propose method perfrect reconstructs side information without high complexity in the encoder side, as transmitting motion vectors from a decoder to an encoder side. Also, at the encoder side, residual signals between reconstructed side information and original frame are adaptively quantized to minimize parity bits to be transmitted to the decoder. The proposed method can effectively allocate bits based on bit error rate of side information. Also, we can achieved bit-saving by transmission of parity bits based on the error correction ability of the LDPC channel decoder, because we can know bit error rate and positions of error bit in encoder side. Experimental results show that the proposed algorithm achieves bit-saving by around 66% and delay of feedback channel, compared with the convntional algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2C
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• pp.219-228
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• 2010

In this paper, performance of RS (Reed-Solomon), turbo and LDPC (low density parity check) code in the binary symmetric erasure channel is investigated. When the average erasure length is reduced, the frequency of short erasures is increased. The RS code shows serious performance degradation in such an environment since decoding is carried out symbol-by-symbol. As the erasure length is increased, however, the RS code shows much improved en-or performance. On the other hand, the message and corresponding parity symbols of the turbo code can be erased at the same time for the long erasures. Accordingly, iterative decoding of the turbo code can not improve error performance any more for such a long erasure. The LDPC code shows little difference in error performance with respect to the variation of the average erasure length due to the virtual interleaving effect. As a result, the LDPC code has much better erasure decoding performance than the RS and turbo code.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.8
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• pp.662-668
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• 2013

Mobile communication systems have been adopting link adaptive transmission schemes such as adaptive modulation and coding (AMC) and hybrid-ARQ (HARQ). Incremental redundancy (IR) HARQ scheme is known to be highly efficient in terms of throughput and power consumption and can be a good solution for mobile communication systems. In this paper, we propose an IR-HARQ scheme based on dual-diagonal parity-type block LDPC codes in which we define a transmission priority of coded bits and propose the sub-packet construction rule. We present the throughput performance of IR-HARQ with various modulation and coding and multi-antenna modes. Consequently, the proposed scheme provides the improvement of system throughput by elaborate link adaptation with CQI information.

• Journal of Preventive Medicine and Public Health
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• v.53 no.2
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• pp.117-125
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• 2020

Objectives: This study investigated the role of information and communication technology and women's empowerment in contraceptive discontinuation in Indonesia. Methods: The study used data from the 2017 Indonesia Demographic and Health Survey and monthly contraceptive calendar data. A Gompertz proportional hazards model was used for analysis. Results: The 12-month contraceptive discontinuation rate was higher among women who had used the Internet in the past year, women who were mobile phone owners, and women who reported having fully participated in household decision-making than among their counterparts. These factors significantly impacted the risk of contraceptive discontinuation in Indonesia, even after controlling for contraceptive method, age, parity, contraceptive intent, education, work status, place of residence, and wealth status. Conclusions: After adjustment for the control variables, a higher risk of contraceptive discontinuation was associated with having used the Internet in the past year, owning a mobile phone, and not participating in household decision-making. Higher contraceptive discontinuation risk was also associated with using contraceptive pills, older age, lower parity, intent of spacing births, more education, current unemployment, and rural residence, and the risk was also significantly higher for those in the lowest household wealth quintile than for those in the fourth household wealth quintile. The association of contraceptive discontinuation with the use of modern information and communication technology and relatively disempowerment in household decision-making may imply that information regarding family planning and contraception should be conveyed via social media as part of setting up an eHealth system. This must include a strong communication strategy to empower and educate women in contraceptive decision-making.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7C
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• pp.611-617
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• 2010

In this paper, we investigate the performances of the serial concatenated convolutional codes (SCCC) and low-density parity-check (LDPC) codes on perpendicular magnetic recording (PMR) channels. We discuss the performance of two systems when user bit-densities are 1.7, 2.0, 2.4 and 2.8, respectively. The SCCC system is less complex than LDPC system. The SCCC system consists of recursive systematic convolutional (RSC) codes encoder/decoder, precoder and random interleaver. The decoding algorithm of the SCCC system is the soft message-passing algorithm and the decoding algorithm of the LDPC system is the log domain sum-product algorithm (SPA). When we apply the iterative decoding between channel detector and the error control codes (ECC) decoder, the SCCC system is compatible with the LDPC system even at the high user bit density.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.1
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• pp.188-201
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• 2006

Purpose : This study was conducted to investigate the effect of pregnancy and parity on bone marrow density using Dual Energy X-ray Absorptiometry (DXA) after parturition Methods : The observation cases who was over 20 and under 35 years old just after childbirth were admitted twice to woosuk university hospital from Aug 2000 to July 2005. During the first admission period, we measured the bone marrow density(BMD) using DXA in 13th day, and when the patient came to the hospital just after childbirth again, we followed up the BMD in 13th day. The evaluation index of this report was comparison of the T-score which was about the lumbar spine(L1-L4) BMD and femur neck BMD. Results : The continuous parturition was increased the lumbar spine BMD(P<<0.05), and decreased the femur neck BMD but it had no meaning. In the cases of the parturition interval under 24 months regarded as siblings born within a year of each other, the analysis results of BMD showed increase in lumbar spine BMD. In the cases of the parturition interval over 24 months, there was increased in lumbar BMD, and decreased in femur neck BMD. To the analysis of the weight variation, the increased BMI group has a significant increase in lumbar spine BMD, and the decreased BMI group also increase in lumbar spine BMD but there was no meaning about that. Conclusion : The continuous parturition was increased the lumbar spine BMD.