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Delayless individual-weighting-factors sign subband adaptive filter (IWF-SSAF) algorithms with a band-dependent variable step-size (BDVSS) were recently introduced to achieve a robust convergence performance against the impulsive interference and to avoid an undesirable signal path delay in subband systems. In this paper, we develop a block implementation of the delayless IWF-SSAF algorithm designed for an active impulsive noise control (AINC) system. With the block-processing approach, the proposed delayless block IWF-SSAF algorithm can be implemented more efficiently than the original delayless algorithm regardless of number of subbands, which is verified through the computational analysis. Furthermore, an improved BDVSS version (I-BDVSS) is also proposed by using the multiple auxiliary past gradients, which are given for each band by the block-processing. Finally, the simulation results illustrate that the proposed delayless block IWF-SSAF algorithm with the I-BDVSS, even requiring less computational burden, can achieve a better convergence performance than the original delayless algorithm with the BDVSS under severe impulsive noise control environment.

An X-ray diffraction (XRD) analysis was conducted after separating clay particles from three shards, to analyze the production technique of black pottery excavated from a historical site of ancient Baekje in Seoul, South Korea. Through the analysis, clay minerals and iron oxides that were not recognized in the XRD patterns of the bulk powder samples were identified. A pottery type with a blackened portion from the surface to the margin and the core was estimated to have been produced in a reduction firing environment of less than 900 °C, by detecting illite and magnetite. As for the other blackened pottery, a brown soil color remained in the core, and the presence of illite and kaolin was confirmed. In addition, while magnetite was detected on the black surface and margin, hematite was detected in the core. These results confirm that this type of blackened pottery was produced through reduction firing at a temperature below 550 °C. In particular, the results indicate that there is a new category of pottery, produced by firing at lower temperatures in a reduction atmosphere, previously not reported by research on ancient Baekje black pottery, which could be discovered due to its specific clay particles.

Sang Won Nam,1 Jinwoo Choi,1 Hyun Jeong Jeon,2 Tae Keun Oh,2 Dong-Hwa Lee1 1Department of Internal Medicine, Chungbuk National University Hospital, Cheongju, South Korea; 2Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, South KoreaCorrespondence: Dong-Hwa LeeDepartment of Internal Medicine, Chungbuk National University Hospital, 776, 1sunhwan-Ro, Seowon-Gu, Cheongju-si, Chungcheongbuk-do, 28644, South KoreaTel +82-43-269-7504Fax +82-43-273-3252Email roroko@hanmail.netBackground: Vitamin D receptor (VDR) polymorphisms are associated with osteoporosis, diabetes, immunological diseases, and cancers. However, the association of obesity with VDR polymorphisms has shown inconsistent results, and perhaps it depends upon the characteristics of a population. Therefore, we evaluated the association between BsmI (rs1544410) and ApaI (rs7975232) polymorphisms of VDR and obesity in Korean patients with type 2 diabetes mellitus (T2DM).Methods: A total of 506 patients with T2DM participated in the study. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze BsmI and ApaI polymorphisms; the genotypes were presented as BB, Bb, or bb for BsmI and AA, Aa, or aa for ApaI. Obesity was defined using the body mass index (BMI) with a cutoff level of 25 kg/m2.Results: The prevalence of obesity was higher in patients with the bb genotype than in those with BB or Bb genotypes (48.4% vs 33.9%, P = 0.031). The mean BMI was 25.2 ± 3.5 kg/m2 in patients with bb genotype and 24.1 ± 3.1 kg/m2 in patients with BB or Bb genotypes. Patients with Aa or aa genotypes showed a higher prevalence of obesity than patients with AA genotype (47.6% vs 26.1%, P = 0.043). Glycemic control parameters and lipid profiles did not show significant differences with either polymorphism.Conclusion: To our knowledge, this is the first study to assess the association between VDR polymorphisms and obesity in Korean patients with T2DM. Further studies in larger populations and multiethnic cohorts are needed to validate our findings.Keywords: type 2 diabetes mellitus, obesity, vitamin D, vitamin D receptor gene, polymorphism

End-stage renal disease (ESRD) patients on hemodialysis have poor nutritional status and associated problems such as inflammation and sarcopenia. Blood urea nitrogen (BUN) is an important measure of uremic toxins, and urea reduction is a marker of hemodialysis efficacy. However, a low protein diet for lower BUN could aggravate malnutrition in patients, and optimal pre-dialysis BUN is not defined. We investigated the association of pre-dialysis BUN with patients' comorbidities and the relationship between pre-dialysis BUN and serum albumin as a nutrient marker. Among the 67 patients, the average pre- and post-dialysis BUN were 59.2 and 15.0 mg/dL, respectively, serum creatinine was 10.1 mg/dL, and the average serum albumin was 4.0 g/dL. Patients' age was negatively correlated with serum creatinine (r=-0.277, p0.05) and albumin (r=-0.453, p0.001). Predialysis BUN showed a significant positive correlation with serum albumin (r=0.287, p0.05) and creatinine (r=0.454, p0.001). However, the predialysis BUN was not significantly related to diabetes, coronary artery disease, congestive heart failure, or cerebrovascular disease. Hemodialysis patients with high pre-dialysis BUN and high serum creatinine could be regarded as having good nutritional status. The significance of this study lies in the potential utility of pre-dialysis blood urea nitrogen as an indicator of the nutritional status of patients. Liberal protein intake might be recommended to adequately dialyzed patients.

Background and Aims Elderly population is increasing and the age starting dialysis treatment is also increasing. It could be an ethical issue that we should do or not do start dialysis treatment in the oldest old people such as 10th decade. We investigated duration of dialysis therapy via patients age using National Health Insurance calim data to know dialysis survival of patients via their age. Method Korean National Health Insurance Database was used and excerpted data from the insurance claim of ICD code of dialysis. We included all new patients starting dialysis more than 3 months between 2004 and 2013 and compared dialysis duration among the age group. Patients on dialysis before 2003 were excluded, and patients on kidney transplantation were also excluded. Results Total 208,202 dialysis patients were included via dialysis insurance calim code from about 50,000,000 South Korean population during the year 2003 to 2015. 126,448 patients were excluded due to dialysis before 2003, < 3 months of dialysis duration, kidney transplatation, and to have missing data. Among the final 81,754 patients, 73,969 were hemodialysis and 7,785 were peritoneal dialysis. 47,798 were men and 33,956 were wemen. Observed median dialysis duration of each aged group of 20-40, 41-50, 51-60, 61-70, 71-80, 81-90, and >90 were 5.4 (2.2 - 18.3), 5.0 (1.8 - 17.7), 4.2 (1.5 - 15.1), 3.5 (1.2 - 12.6), 2.7 (0.9 - 10.1), 1.8 (0.5 - 7.1), 1.3 (0.3 - 4.9) years, respectively (p < 0.0001). Comparing with age under 40, dialysis survival hazard ratio of > 40, > 50, > 60, > 70, > 80, and > 90 were 1.493, 2.452, 3.762, 6.113, 9.787, and 15.326, respectively (p < 0.0001). Survival probability of the patients by the age was demonstrated in the figure 1. Lowest socio-econonic status and highest Charson-Comorbidity group showed highest hazard ratio of dialysis mortality, and peritoneal dialysis showed longer dialysis duration (HR 0.704, 95% CI of 0.69 - 0.74, p < 0.0001). Conclusion We concluded that dialysis durability by the age was rapidly decreased after 70 years old. As the longest patients survival of > 90 years were less than 5 years, we should consider patients’ general performance when starting dialysis of oldest old patients.

일반적인 자동제어 기계 장치 등에 사용되고 있는 적외선 인체 감지 센서 모듈은 초전형 적외선 (pyroelectric infrared) 센서, 증폭기, 그리고 비교기로 구성되어 있으며 인체와 물체의 구분 용도로 사용되고 있다. 특히, 초전형 적외선 센서는 정지된 인체로부터 적외선 감지를 못하고, 가시광선의 흔들림과 굴절된 빛에 오동작 감지 신호가 발생하는 문제가 있다. 최근의 열전대열 적외선 (thermopile infrared) 센서는 실리콘 필터를 통해 6um∼13um 적외선 파장 대역 신호를 감지할 수 있어서 가시광선 영향이 최소화되고, 정지된 인체로부터도 적외선을 감지할 수 있다. 그러나, 열전대열 적외선 센서에서는 초전형 적외선 센서와 비교하여 인체 감지 거리가 상대적으로 짧고, 주변 온도 감지 출력이 적외선 감지 신호에 가중되어 출력되는 문제가 있다. 본 논문은 인체 감지 거리가 확장된 열전대열 적외선 센서 모듈 회로를 제안한다. 제안된 감지 거리 확장 모듈은 고 이득 증폭기와 온도 보상 회로의 2단으로 구성되어 있다. 제안 모듈은 시제품 보드로 제작 및 실험되었고, 최근의 상업용 열전대열 적외선 센서 모듈과 비교해도 감지 거리가 약 3 배 확장되어 3.0m 거리에서도 안정적인 인체 감지 성능을 보였다

Sign subband adaptive filter algorithms with individual weighting factors (IWF-SSAF) were recently proposed to achieve improved convergence performance in impulsive noise environments by fully utilizing the decorrelating property of subband adaptive filters. However, such sign subband adaptive filter (SSAF) algorithms may have an inherent signal path delay problem for real-time applications, and thus, can be restrictively applied. In this paper, a delayless IWF-SSAF with band-dependent variable step-sizes (BD-VSS), robust in impulsive noise environments, is proposed for real-time applications, whereby two delayless filter structures developed for the $\ell _2$ -norm-based SAF are employed along with the IWF-SSAF. In particular, a BD-VSS algorithm is also introduced for better convergence by applying the recent $\ell _1$ -norm minimization technique to respective subband. Finally, the performance of the proposed delayless IWF-SSAF with BD-VSS is verified in various impulsive interference environments such as system identification with impulsive noise, acoustic echo cancellation in a double-talk scenario, and active impulsive noise control.

In this paper, a variable-parameter arctangent-cost-function based NLMS (VP-Arc-NLMS) robust against impulsive interferences is proposed to solve the trade-off between tracking capability and low misadjustment. In particular, the energy of the filter update is controlled to be constrained by the maximum of the variable-parameter cost function. Finally, improved convergence and MSD performances of the proposed VP-Arc-NLMS are verified by considering system identification in an impulsive interference environment.

In wireless communications, knowledge of the signal-to-noise ratio is required in diverse communication applications. In this paper, we derive the variance of the maximum likelihood estimator in the data-aided and non-data-aided schemes for determining the optimal shrinkage factor. The shrinkage factor is usually the constant that is multiplied by the unbiased estimate and it increases the bias slightly while considerably decreasing the variance so that the overall mean squared error decreases. The closed-form biased estimators for binary-phase-shift-keying and quadrature-phase-shift-keying systems are then obtained. Simulation results show that the mean squared error of the proposed method is lower than that of the maximum likelihood method for low and moderate signal-to-noise ratio conditions.

In this paper, a new affine projection sign algorithm with a variable step-size, robust in impulsive noise environments, is proposed. For that purpose, l1-norm of the a posteriori error vector is minimized under a box constraint on the step-size. Since the proposed l1-norm minimization problem is non-differentiable convex one, an efficient numerical procedure is developed for the affine projection structure algorithm. Finally, it is demonstrated that the proposed algorithm, not requiring any a priori knowledge, yields more robust convergence in various impulsive noise environments than conventional algorithms with robustness to outliers and recent variable step-size algorithms with a priori information.

In this study the nanofiltration (NF) membrane treatment of a sulfuric acid waste solutions containing copper ion () discharging from the etching processes of the printed circuit board (PCB) manufacturing industry has been studied for the recycling of acid etching solution. SelRO MPS-34 4040 NF membrane from Koch company was tested to obtain the basic NF data for recycling of etching solution and separation efficiency (total rejection) of copper ion. NF experiments were carried out with a cross-flow membrane filtration laboratory system. The permeate flux was decreased with the increasing copper ion concentration in sulfuric acid solution and lowering pH of acid solution, and its value was the range of . Total rejection of copper ion was decreased with the increasing copper ion concentration, lowering pH of acid solution and decreasing cross-flow rate. The total rejection of copper ion was more than 70% at the experimental condition. The SelRO MPS-34 4040 NF membrane was represented the stable flux and rejection for 1 year operation.

A closed-form design of a two-dimensional (2D) finite impulse response (FIR) filter with circular, rectangular, fan or quadrant-fan shapes in the passband region is presented. The computationally efficient 2D FIR filter can be implemented using frequency transformation and sampling-kernel-based interpolation instead of an optimisation algorithm. When compared with the existing method, the proposed method reduces 90% of multiplications for filtering. Several design examples are demonstrated to verify the performance of the proposed design.

Television audience measurement is intended to collect information on the audiences watching a specific television program at a particular time. This information is crucial for television broadcasters and advertisers because they need to provide right television programs and commercials to right audiences to maximize their investments in broadcasting. For accurate measurements, a panel of representative audiences must be selected judiciously so that it accurately represents the entire target audience group. However, it is hard to secure a proper number of target audiences due to the expensive and cumbersome installations of measurement equipments. To resolve this issue in panel selection, we propose a novel television audience measurement framework using pervasive smart devices such as a smartphone. In the proposed framework, a short audio signal from a television set is recorded by a personal smart device and is sent to an audio matching server for the identification of the television program shown by the television set. For effective identification, we propose an accurate audio matching algorithm based on spectral coherence and efficient implementation techniques that exploit the inherent parallelism in the algorithm. To verify the plausibility of the framework and the effectiveness of the audio matching algorithm, we conduct experiments with diverse genres of television programs under various recording conditions.

Based on the conventional 2-6GHz digital frequency discriminator (DFD) using the phase unwrapping and least-squares techniques, we propose a new 2-18GHz DFD. To compensate for lowered-precision frequency estimation due to the expanded bandwidth, the proposed DFD design employs more delay lines, accordingly accompanying high complexity. Thus, a new computationally efficient frequency estimation algorithm is also presented to overcome such high computational burden. More specifically, the proposed frequency estimation algorithm is basically based on the conventional phase unwrapping technique, along with a new candidates selection for the unwrapped phases under the condition that the phase margin is known. As a result, the computational burden required for the least-squares technique can be reduced. Finally, simulation results are provided to demonstrate the effectiveness of the proposed approach, compared with those of the conventional DFD`s.

This paper introduces a novel approach to estimate the systolic and diastolic blood pressure ratios (SBPR and DBPR) based on the maximum amplitude algorithm (MAA) using a Gaussian mixture regression (GMR). The relevant features, which clearly discriminate the SBPR and DBPR according to the targeted groups, are selected in a feature vector. The selected feature vector is then represented by the Gaussian mixture model. The SBPR and DBPR are subsequently obtained with the help of the GMR and then mapped back to SBP and DBP values that are more accurate than those obtained with the conventional MAA method.

In this paper, an improved FastICA algorithm is proposed for blind source separation by using a sixth-order Newton's method for finding the solutions of the nonlinear equations much faster than other Newton-type iterative methods. In particular, the proposed method has comparable separation performance, fewer iterations, and faster convergence speed.