• Journal of Communications and Networks
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• 제17권6호
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• pp.609-621
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• 2015

Recently, a variety of reduced complexity soft-in soft-output detection algorithms have been introduced for iterative detection and decoding (IDD) systems. However, it is still challenging to implement soft-in soft-output detectors for MIMO systems due to heavy burden in computational complexity. In this paper, we propose a soft detection algorithm for MIMO systems which performs close to the full dimensional joint detection, yet offers significant complexity reduction over the existing detectors. The proposed algorithm, referred to as soft-input soft-output successive group (SSG) detector, detects a subset of symbols (called a symbol group) successively using a deliberately designed preprocessing to suppress the inter-group interference. In fact, the proposed preprocessor mitigates the effect of the interfering symbol groups successively using a priori information of the undetected groups and a posteriori information of the detected groups. Simulation results on realistic MIMO systems demonstrate that the proposed SSG detector achieves considerable complexity reduction over the conventional approaches with negligible performance loss.

• The Korean Journal of Pain
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• 제28권2호
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• pp.105-108
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• 2015

Background: The most definitive diagnosis of neck pain caused by facet joints can be obtained through cervical medial branch blocks (CMBBs). However, intravascular injections need to be carefully monitored, as they can increase the risk of false-negative blocks when diagnosing cervical facet joint syndrome. In addition, intravascular injections can cause neurologic deficits such as spinal infarction or cerebral infarction. Digital subtraction angiography (DSA) is a radiological technique that can be used to clearly visualize the blood vessels from surrounding bones or dense soft tissues. The purpose of this study was to compare the rate of detection of intravascular injections during CMBBs using DSA and static images obtained through conventional fluoroscopy. Methods: Seventy-two patients were included, and a total of 178 CMBBs were performed. The respective incidences of intravascular injections during CMBBs using DSA and static images from conventional fluoroscopy were measured. Results: A total of 178 CMBBs were performed on 72 patients. All cases of intravascular injections evidenced by the static images were detected by the DSAs. The detection rate of intravascular injections was higher from DSA images than from static images (10.7% vs. 1.7%, P < 0.001). Conclusions: According to these findings, the use of DSA can improve the detection rate of intravascular injections during CMBBs. The use of DSA may therefore lead to an increase in the diagnostic and therapeutic value of CMBBs. In addition, it can decrease the incidence of potential side effects during CMBBs.

• 재활복지공학회논문지
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• 제9권1호
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• pp.67-72
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• 2015

팔의 사용이 자유롭지 못한 장애인들을 위하여 발의 움직임 검출을 통하여 로봇 팔을 제어할 수 있는 시스템을 구현하였다. 발의 움직임에 대한 영상을 얻기 위하여 양쪽 발 앞에 두 대의 카메라를 설치하였으며, 획득된 영상에 대해 LabView 기반 Vision Assistant를 이용하여 다중 관심영역을 설정한 후, 좌/우영역내에서 검출된 좌/우, 상/하 엣지를 기반으로 발의 움직임을 검출하였다. 좌/우 두발의 영상으로부터 좌/우 엣지와 상/하 엣지 검출 수에 따라 6관절 로봇 팔을 제어할 수 있는 제어용 데이터를 시리얼 통신을 통해 전송한 후 로봇 팔을 발로 상/하, 좌/우 제어할 수 있는 시스템을 구현하였다. 실험 결과 0.5초 이내의 반응속도와 88% 이상의 동작 인식률을 얻을 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4891-4894
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• 2015

Background: To evaluate the value of combined detection of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1), and carbohydrateantigen 125 (CA125) for the clinical diagnosis of nonsmall cell lung cancer (NSCLC). Materials and Methods: Serum CEA, CYFRA21-1 and CA125 were assessed in 140 patients with NSCLC, 90 patients with benign lung disease and 90 normal control subjects, and differences of expression were compared in each group, and joint effects of these tumor markers in the diagnosis of NSCLC were analyzed. Results: Serum CEA, CYFRA21-1 and CA125 in patients with NSCLC were significantly higher than those with benign lung disease and normal controls (P<0.05). The sensitivity of CEA, CYFRA21-1 and CA125 were 49.45%, 59.67%, and 44.87% respectively. As expected, combinations of these tumor markers improved their sensitivity for NSCLC. The combined detection of CEA + CYFRA21-1 was the most cost-effective combination which had higher sensitivity and specificity in NSCLC. Elevation of serum CEA and CYFRA21-1 was significantly associated with pathological types (P<0.05) and elevation of serum CEA, CYFRA21-1 and CA125 was significantly associated with TNM staging (P<0.05). Conclusions: Single measurement of CEA, CYFRA21-1 and CA125 is of diagnostic value in the diagnosis of lung cancer, and a joint detection of these three tumor markers, could greatly improve the sensitivity of diagnosis on NSCLC. Combined detection of CEA + CYFRA21-1 proved to be the most economic and practical strategy in diagnosis of NSCLC, which can be used to screen the high-risk group.

• Smart Structures and Systems
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• 제29권1호
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• pp.167-179
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• 2022

This article develops a long-term condition assessment method for stay cables in cable stayed bridges using the monitored cable tension forces under operational condition. Based on the concept of influence surface, the matched cable tension ratio of two cables located at the same side (either in the upstream side or downstream side) is theoretically proven to be related to the condition of stay cables and independent of the positions of vehicles on the bridge. A sensor grouping scheme is designed to ensure that reliable damage detection result can be obtained even when sensor fault occurs in the neighbor of the damaged cable. Cable forces measured from an in-service cable-stayed bridge in China are used to demonstrate the accuracy and effectiveness of the proposed method. Damage detection results show that the proposed approach is sensitive to the rupture of wire damage in a specific cable and is robust to environmental effects, measurement noise, sensor fault and different traffic patterns. Using the damage sensitive feature in the proposed approach, the metrics such as accuracy, precision, recall and F1 score, which are used to evaluate the performance of damage detection, are 97.97%, 95.08%, 100% and 97.48%, respectively. These results indicate that the proposed approach can reliably detect the damage in stay cables. In addition, the proposed approach is efficient and promising with applications to the field monitoring of cables in cable-stayed bridges.

• Smart Structures and Systems
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• 제32권1호
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• pp.23-35
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• 2023

Steel bolted joint is an important part of steel structure, and its damage directly affects the bearing capacity and durability of steel structure. Currently, the existing research mainly focuses on the identification of corroded bolts and corroded bolts respectively, and there are few studies on multiple states. A detection framework of corroded and loosened bolts is proposed in this study, and the innovations can be summarized as follows: (i) Vision Transformer (ViT) is introduced to replace the third and fourth C3 module of you-only-look-once version 5s (YOLOv5s) algorithm, which increases the attention weights of feature channels and the feature extraction capability. (ii) Three states of the steel bolts are considered, including corroded bolt, bolt missing and clean bolt. (iii) Line segment detector (LSD) is introduced for bolt rotation angle calculation, which realizes bolt looseness detection. The improved YOLOv5s model was validated on the dataset, and the mean average precision (mAP) was increased from 0.902 to 0.952. In terms of a lab-scale joint, the performance of the LSD algorithm and the Hough transform was compared from different perspective angles. The error value of bolt loosening angle of the LSD algorithm is controlled within 1.09%, less than 8.91% of the Hough transform. Furthermore, the proposed framework was applied to fullscale joints of a steel bridge in China. Synthetic images of loosened bolts were successfully identified and the multiple states were well detected. Therefore, the proposed framework can be alternative of monitoring steel bolted joints for management department.

• 한국전문물리치료학회지
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• 제3권2호
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• pp.95-105
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• 1996

지금까지의 내용을 요약하면 먼저, 인체의 각 관절 주위에는 관절의 움직임과 위치를 파악하는 감지기 역할을 하는 기계적 감수기가 있다. 이러한 감수기는 크게 네가지로 구분되어지는데 대개 I형 감수기, II형 감수기 등의 용어를 사용한다. 각각의 감수기의 특성(표 2.)을 알아보면, 루피니(Ruffini)감각기와 유사한 모양을 하고 있는 I형 관절감수기는 주로 운동의 속도(speed)와 방향(direction)을 감지(detection) 하며, 파시니안(Pacinian)감각기와 유사한 형태를 하고 있는 II형 관절감수기는 매우 작은 움직임에 대한 감지를 하는데, 예를 들어 속도가 가속(acceleration)되는 것과 같은 움직임 등을 알아낸다. 이외에 골지건과 비슷한 모습을 하고 있는 III형 관절감수기는 운동의 자세(position)와 방향에 대한 정보를 전달하게 된다 (Carpanter, 1990). 관절의 자세 유지 혹은 안정성 즉, 정적(static) 운동에 주로 관여하는 I형 관절감수기와, 역동적(dynamic)인 운동에 감지를 주로 하는 II형 관절감수기는 진동(oscillation)자극에 잘 촉진된다. 이러한 자극은 동통이 심하게 발생된 관절에 나타나는 근육의 과긴장(hypertonicity)과 동통을 경감시킬 수 있다. III형 관절감수기는 억제 (inhibitory)감수기라 할 수 있는데, 골지건(golgi tendon organ)의 기능과 매우 관련이 깊다. 이 감수기는 관절의 가동범위를 기계적인 자극으로 증가시키기 위해 관절의 가동 끝범위에서 강한 신장(strong strectch)이나 thrust 기술로 감수기를 촉진할 수 있다. 이러한 자극은 결국 근육에 이완을 얻게 할 수 있다. 위에서 언급한 관절 주위의 조직에 분포한 특별한 기계적 감지를 환자들의 임상 증상에 따라 선택적으로 자극하는 치료를 적용할 수 있다면, 현재 물리치료사들이 적용하고 있는 관절 가동운동을 좀더 전문적인 수준으로 수행할 수 있을 것이다.

• 대한미생물학회지
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• 제35권2호
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• pp.191-201
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• 2000

The viruses of Herpes Simplex Virus 1 (HSV-1), Herpes Simplex Virus 2 (HSV-2) and Varicella-Zoster virus (VZV) which belong to the alpha herpes subfamily are important human pathogens. When eruptions were not fully developed from these viral infections, clinical diagnosis was not always easy and required virological confirmation test. The above viruses were reactivated in individuals who were compromised in immune competence for one reason or another. Polymerase chain reaction (PCR) enables rapid and sensitive detection of HSV and VZV DNAs. Its sensitivity was largely influenced by choice of primers. Authors conducted a study to detect of those three viruses in human specimens including vesicle fluid and joint fluid and serum using PCR methods. Primers used for this study were the general primer pair GPHV-RU which was known to amplify within the genes enjoying the highest degree of homology between UL15 of HSV and UL42 of VZV. PCR with primers hybridized pair GPHV-RU amplifies a 396 bp with THP-1 and HSV-2 standard strain DNA and 405 bp with VZV standard strain DNA. Restriction enzyme cleavage with HpaII and DdeI were used to detect and distinguish DNAs of THP-1 and HSV-2 and VZV. The purpose of this study was a rapid and easy detection of VZV and THP-1 or HSV-2 from various clinical specimens (vesicle fluid, serum and joint fluid) by PCR method. Used methods were: HSV PCR with primer 1, 2 and HpaII RE digestion; VZV nested PCR; HSV PCR with primer A, Band BssHII RE digestion. 1) In 33 cases (33/42, 78.6%) VZV was detected single or mixed infection from 42 clinical specimens which included vesicle fluid (5), serum form respiratory infected children (10), serum from immune suppressed adult cancer patients (7) and joint fluid from arthritis patients (20). 2) In 20 cases (20/42, 47.6%) HSV was detected singly or mixed infection and 19 of those cases were HSV-2 and 1 case was THP-1. 3) In 19 cases (19/42, 45.2%) VZV was singly detected which included serum from respiratory infected children (6 cases), joint fluid from arthritis patients (9 cases), vesicle fluid (2 cases) and serum form immunosuppressed cancer patients (2 cases). 4) HSV was singly detected in 6 cases (6/42, 14.3%) which included joint fluid from arthritis patients (5 cases) and serum form respiratory infected children (1 cases). 5) 14 cases of VZV and HSV mixed infection (14/42, 33.3%) were detected. They included vesicle fluid (3 cases), serum form immunosuppressed cancer patients (4 cases), serum from respiratory infected children (2 cases) and joint fluid from arthritis patients (5 cases). 6) HSV-1 and HSV-2 detection and typing by HSV PCR with primer A, Band BssHII RE digestion method was more sensitive and the results were easier to detect than on other method.

• 한국통신학회논문지
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• 제30권6C호
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• pp.541-550
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• 2005

이 논문에서는 모수와 비모수 신호 검파에서 널리 쓰이는 네 통계량 사이의 결합 분포와 상관계수를 얻는다. 아울러, 상관계수들의 상한과 하한을 얻고, 상관계수들 사이의 눈여겨볼 만한 관계를 살펴본다. 또한, 몇 가지 분포에서 얻은 상관계수 값을 표와 그림으로 정리하여 쉽게 참고할 수 있도록 하였다. 이 논문에서 얻은 결과는 여러 검정 통계량을 서로 견주어 볼 때 쓸모 있을 것이다.

• Smart Structures and Systems
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• 제16권2호
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• pp.281-294
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• 2015

Bolted joint connection is the most commonly used connection element in structures and devices. The loosening due to external dynamic loads cannot be observed and measured easily and may cause catastrophic loss especially in an extreme requirement and/or environment. In this paper, an innovative Real-time Cross-Correlation Method (RCCM) for monitoring of the bolted joint loosening was proposed. We apply time reversal process on stress wave propagation to obtain correlation signal. The correlation signal's peak amplitude represents the cross-correlation between the loosening state and the baseline working state; therefore, it can detect the state of loosening. Since the bolt states are uncorrelated with noise, the peak amplitude will not be affected by noise and disturbance while it increases SNR level and increases the measured signals' reliability. The correlation process is carried out online through physical wave propagation without any other post offline complicated analyses and calculations. We implemented the proposed RCCM on a single bolt/nut joint experimental device to quantitatively detect the loosening states successfully. After that we implemented the proposed method on a real large structure (reaction wall) with multiple bolted joint connections. Loosening indexes were built for both experiments to indicate the loosening states. Finally, we demonstrated the proposed method's great anti-noise and/or disturbance ability. In the instrumentation, we simply mounted Lead Zirconium Titanate (PZT) patches on the device/structure surface without any modifications of the bolted connection. The low-cost PZTs used as actuators and sensors for active sensing are easily extended to a sensing network for large scale bolted joint network monitoring.