• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.1-14
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• 2023

The overuse of pesticides in agricultural sectors exposes people to food contamination. Pesticides are toxic to humans and can have both acute and chronic health effects. To protect food consumers from the adverse effects of pesticides, a rapid monitoring system of the residues is in dire need. Molecularly imprinted polymer (MIP) on a screen-printed electrode (SPE) is a leading and promising electrochemical sensing approach for the detection of several residues including pesticides. Despite the huge development in analytical instrumentation developed for contaminant detection in recent years such as HPLC and GC/MS, these conventional techniques are time-consuming and labor-intensive. Additionally, the imprinted SPE detection system offers a simple portable setup where all electrodes are integrated into a single strip, and a more affordable approach compared to MIP attached to traditional rod electrodes. Recently, numerous reviews have been published on the production and sensing applications of MIPs however, the research field lacks reviews on the use of MIPs on electrochemical sensors utilizing the SPE technology. This paper presents a distinguished overview of the MIP technique used on bare and modified SPEs for the detection of pesticides from four recent publications which are malathion, chlorpyrifos, paraoxon and cyhexatin. Different molecular imprint routes were used to prepare these biomimetic sensors including solution polymerization, thermal polymerization, and electropolymerization. The unique characteristics of each MIP-modified SPE are discussed and the comparison among the findings of the papers is critically reviewed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.2
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• pp.348-369
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• 2024

With the advancement of Industry 4.0 and Industrial Internet of Things (IIoT), manufacturing increasingly seeks automation and intelligence. Temperature and vibration monitoring are essential for machinery health. Traditional abnormal state detection methodologies often overlook the intricate frequency characteristics inherent in vibration time series and are susceptible to erroneously reconstructing temperature abnormalities due to the highly similar waveforms. To address these limitations, we introduce synergistic, end-to-end, unsupervised Frequency-Time Domain Memory-Enhanced Autoencoders (FTD-MAE) capable of identifying abnormalities in both temperature and vibration datasets. This model is adept at accommodating time series with variable frequency complexities and mitigates the risk of overgeneralization. Initially, the frequency domain encoder processes the spectrogram generated through Short-Time Fourier Transform (STFT), while the time domain encoder interprets the raw time series. This results in two disparate sets of latent representations. Subsequently, these are subjected to a memory mechanism and a limiting function, which numerically constrain each memory term. These processed terms are then amalgamated to create two unified, novel representations that the decoder leverages to produce reconstructed samples. Furthermore, the model employs Spectral Entropy to dynamically assess the frequency complexity of the time series, which, in turn, calibrates the weightage attributed to the loss functions of the individual branches, thereby generating definitive abnormal scores. Through extensive experiments, FTD-MAE achieved an average ACC and F1 of 0.9826 and 0.9808 on the CMHS and CWRU datasets, respectively. Compared to the best representative model, the ACC increased by 0.2114 and the F1 by 0.1876.

• Korean Journal of Clinical Laboratory Science
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• v.41 no.1
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• pp.11-23
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• 2009

Chromosomal rearrangements are major pathology in hematological malignancies. The detection of minimal residual disease (MRD) for these gene rearrangements helps in monitoring treatment outcomes and predicting prognosis of patients. Recently, quantification of these gene transcripts based on real-time quantitative polymerase chain reaction (RQ-PCR) has been used as MRD detection. The purpose of this study is to ensure the usefulness of the RQ-PCR technique for detecting MRD in hamatological malignancy patients. The patients had been diagnosed to AML1-ETO positive AML, PML-RARa positive AML and BCR-ABL positive MPN at Chonnam National University Hwasun Hospital from Jan. 2006 to Aug. 2008. The fusion transcript was quntified by RQ-PCR and analyzed in comparison to conventional cytogenetics, FISH and RT-PCR. The fusion gene transcript was quantified by RQ-PCR in 57 samples from 14 patients with AML1-ETO positive AML, 79 samples from 27 patients with PML-RARa positive AML and 108 samples from 36 patients with CML. At diagnosis, the quantitative fusion transcripts for AM1-ETO, PML-RARa and BCR-ABL showed the range of 0.485552651~10.82233683 (mean 3.782217131, SD 2.998052348), 0.005300395~0.29267494 (mean 0.056901315, SD 0.080131381) and 0.1293929~12.94826849 (mean 1.701935665, SD 2.200913158). The increase of AML1-ETO fusion gene transcripts preceded morphologic relapse in two patients. Quantification of fusion gene transcripts by RQ-PCR could detected MRD in samples which were negative by in cytogenetic analysis or FISH. Our findings indicated that quantitative analysis of AML1-ETO, PML-RARa and BCR-ABL transcripts by RQ-PCR might be a useful tool for the monitoring of minimal residual disease in hematological malignancies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1A
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• pp.1-10
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• 2012

Along with the development of coasts, islands and mountains, the demand of long-span bridges increases which, in turn, brings forth the construction of cable-supported bridges like suspension and cable-stayed bridges. There are various types of statically indeterminate structures widely applied that supported the main girder with stay cables, main cables, hanger cables with aesthetic structural appearance. As to the cable-supported bridges, the health monitoring of a bridge can be identified by measuring tension force on cable repeatedly. The tension force on cable is measured either by direct measurement of stress of cable using load cell or hydraulic jack, or by vibration method estimating tension force using cable shape and measured dynamic characteristics. In this study, a method to estimate dynamic characteristics of hanger cables by using a digital image processing is suggested. Digital images are acquired by a portable digital camcorder, which is the sensor to remotely measure dynamic responses considering convenient and economical aspects for use. A digital image correlation(DIC) technique is applied for digital image processing, and an image transform function(ITF) to correct the geometric distortion induced from the deformed images is used to estimate subpixel. And, the correction of motion of vision-based measurement system using a fixed object in an image without installing additional sensor can be enhanced the resolution of dynamic responses and modal frequencies of hanger cables.

• Smart Structures and Systems
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• v.10 no.2
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• pp.131-154
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• 2012

In this paper, it is aimed to determine the seismic behaviour of highway bridges by nondestructive testing using ambient vibration measurements. Eynel Highway Bridge which has arch type structural system with a total length of 216 m and located in the Ayvaclk county of Samsun, Turkey is selected as an application. The bridge connects the villages which are separated with Suat U$\breve{g}$urlu Dam Lake. A three dimensional finite element model is first established for a highway bridge using project drawings and an analytical modal analysis is then performed to generate natural frequencies and mode shapes in the three orthogonal directions. The ambient vibration measurements are carried out on the bridge deck under natural excitation such as traffic, human walking and wind loads using Operational Modal Analysis. Sensitive seismic accelerometers are used to collect signals obtained from the experimental tests. To obtain experimental dynamic characteristics, two output-only system identification techniques are employed namely, Enhanced Frequency Domain Decomposition technique in the frequency domain and Stochastic Subspace Identification technique in time domain. Analytical and experimental dynamic characteristic are compared with each other and finite element model of the bridge is updated by changing of boundary conditions to reduce the differences between the results. It is demonstrated that the ambient vibration measurements are enough to identify the most significant modes of highway bridges. After finite element model updating, maximum differences between the natural frequencies are reduced averagely from 23% to 3%. The updated finite element model reflects the dynamic characteristics of the bridge better, and it can be used to predict the dynamic response under complex external forces. It is also helpful for further damage identification and health condition monitoring. Analytical model of the bridge before and after model updating is analyzed using 1992 Erzincan earthquake record to determine the seismic behaviour. It can be seen from the analysis results that displacements increase by the height of bridge columns and along to middle point of the deck and main arches. Bending moments have an increasing trend along to first and last 50 m and have a decreasing trend long to the middle of the main arches.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.170-189
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• 2021

Environmental DNA (eDNA) is a genetic material derived from organisms in various environments (water, soil, and air). eDNA has many advantages, such as high sensitivity, short investigation time, investigation safety, and accurate species identification. For this reason, it is used in various fields, such as biological monitoring and searching for harmful and endangered organisms. To collect eDNA from a freshwater ecosystem, it is necessary to consider the target organism and gene and a wide variety of items, such as on-site filtration and eDNA preservation methods. In particular, the method of collecting eDNA from the environment is directly related to the eDNA concentration, and when collecting eDNA using an appropriate collection method, accurate (good quality) analysis results can be obtained. In addition, in preserving and extracting eDNA collected from the freshwater ecosystem, when an accurate method is used, the concentration of eDNA distributed in the field can be accurately analyzed. Therefore, for researchers at the initial stage of eDNA research, the eDNA technology poses a difficult barrier to overcome. Thus, basic knowledge of eDNA surveys is necessary. In this study, we introduced sampling of eDNA and transport of sampled eDNA in aquatic ecosystems and extraction methods for eDNA in the laboratory. In addition, we introduced simpler and more efficient eDNA collection tools. On this basis, we hope that the eDNA technique could be more widely used to study aquatic ecosystems and help researchers who are starting to use the eDNA technique.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.20-32
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• 2008

Runoff characteristics of the Oedocheon in Jeju island were investigated using the long-term stream stage monitoring data. At the Cheonah valley in the upstream area and Oedocheon downstream, annual runoff occurred 21 and 12 times, respectively, and their average runoff periods were 21 days and 12 days, respectively. Stream stage response time to rainfall was 4 hours, and storm-water transfer from the upstream, Cheonah valley, to the Oedocheon downstream took about 2 hours. The stream discharge measurements had been carried out from Feb. 2004 to Jul. 2005, and showed that normal discharge of the Oedocheon was 0.39 $m^3$/sec in average. Stage-discharge curves were developed to estimate base flow (normal discharge) and (direct) surface runoff. The base flow separations by a numerical filtering technique illustrated that annual surface runoff and base flow accounted respectively for 31.8${\sim}$36.5%, 63.5${\sim}$68.2% of the total stream discharge.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.335-340
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• 2010

In accordance with the increasing possibility that the new and reoccurring epidemics continuously appearing abroad flow into Korea, it is very important to evaluate the efficiency of quarantine management projects of National Quarantine Station. This study adopted the pairwise comparison approach using the analytical hierarchy process(AHP) that has been recognized with its scientific adequacy for allocating the weight, the relative importance of evaluation components. AHP technique is evaluated to be distinguished in measuring the impact by making hierarchy of, simplifying and systemizing the complicated multi-criteria decision making problems. The weights by evaluation indexes were 0.2 in the organization evaluation field and 0.8 in the service and program field. The quarantine business showed the highest value, 0.45, in the service and program field. The indexes were classified into the upper category (organization evaluation field, service and program evaluation field) and lower category (input/process/result/quarantine field, inspection field, hygiene management field, pathogenic organ investigation and monitoring field, epidemics prevention promotion/education field). The evaluation indexes that were finally selected were applied to the actual businesses in National Quarantine Station. Next, the minimum evaluation indexes were selected and so the evaluation system on the businesses in National Quarantine Station was more systemized.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.454-459
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• 2008

하천의 건강성을 유지하고 수환경의 정상적인 기능을 회복하기 위해서는 수서생물들에게 알맞은 서식환경 조성, 점오염원 및 비점오염원 차단, 적절한 유량과 같은 다양한 조건이 요구된다(Gore 1895; Gore et al. 1989). 이 중 유량은 수생태계를 이루는 물리적, 화학적, 생물학적 요소들 가운데 기본이 된다고 할 수 있다(Bunn and Arthington 2002; Nilsson and Svedmark 2002; Arthington et al. 2006). 국내 하천관리를 위한 하천유지유량의 산정에서 고려하고 있는 갈수량, 하천생태계, 하천수질 등 8가지 항목 가운데 최근 생태계와 환경에 대한 사회적 국민적 관심이 증가하면서 하천생태계를 고려한 환경유량의 중요성이 부각되었으나, 현실적으로 생태계를 고려한 정량적 조사자료 구축 및 환경유량산정 등의 객관적 자료는 미흡한 실정이다. 특히, 과거 해당수계 및 하천의 어류분포 현황 파악을 중심으로 이루어진 어류조사는 환경유량 산정 시 기초자료로 활용하거나 직 간접적으로 어류상이 변화하는 원인을 분석하는 자료로 활용하기에는 객관성이 결여되어 있다고 할 수 있다. 어류모니터링 기법 확립은 환경유량산정에 있어 요구되는 정량화와 자료의 객관성을 높이기 위한 작업으로 문헌조사와 청문조사를 포함한 사전조사, 현장조사, 조사결과 정리, 고찰 등의 총 4가지 과정을 기본으로 실시하는 것으로 정하였다(그림. 1), 청문조사와 문헌조사 등의 사전조사를 통해 기존자료를 확보하고 현장의 답사, 조사구간, 방법, 시기 등의 선정을 통해 두 번째 단계인 현장조사의 효율성을 높였다. 현장조사에서는 어류분포 현황 외에도 해당지점의 하상재료, 식생, 유속, 수심, 수질 등 조사지점의 수 환경요소 전반을 기록하여 어류의 서식과 물리 화학적 수환경과의 상호관계를 파악하고자 하였다. 마지막으로 고찰단계에서는 조사 대상 지역 전반적인 어류상 특징과 함께 보호종, 한국고유종, 외래도입종 출현유무 및 빈도, 물리적, 화학적 수환경의 특징, 수환경에 따른 어류상 특징 등의 분석과 함께 조사하천의 건강성을 평가하고자 하였다. 본 연구는 어류모니터링 기법 확립을 통해 환경유량산정 시 요구되는 객관적 기초자료를 구축하고 나아가 오염물질 유입, 하천정비사업 등의 각종 교란요인에 의해 발생할 수 있는 문제점들에 능등적으로 대처하고 교란에 의해 악화된 수환경의 복원을 위해 요구되는 객관적 기초자료 생산에 목적이 있다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.4
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• pp.61-68
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• 2011

Event-based service technology integrate service to detect events that occur in real time by analyzing the response. Is the core technology for real-time business and ubiquitous service environment construction. Is required event-based service technology on business processes in real-time business environment that providing rapid response to changing and custom service using a variety of information real-time monitoring and analysis in ubiquitous service environment. Last event-driven business processes can be used as a CEP(Complex Event Processing). The core of CEP technology, the event from multiple event sources analysis of events affecting and the way to handle action, is detect complex event to user. In previous studies, an event occurs that continue to perform without the need for partial operations. so many operations and spend a lot of memory is a problem. To solve these problems, event detection technique is proposed that large streams of data without processing any events, registered to configure a complex event occurs when all events in the application layer, complex event processing. The proposed method, first using a bitmap index to manage the event occurs. The complex events of the last event in response to define a trigger event. The occurrence of an event to display a bitmap index, a composite event occurrence of all event to configure the test through the point at which a trigger event occurs. Is proposed, If any event occurs to perform the operation. The proposed scheme perform operations when all event occurs without events having to perform each of the tests. As a result, avoid unnecessary operations and reducing the number of events to handle the increased efficiency of operations.