• Title/Summary/Keyword: Detection sensitivity

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Tool Fracture Detection in Milling Process (II) -Part 2: Tool Fracture Detection in Rough Milling Using Spindle Motor Current- (밀링 공정시 공구 파손 검출 (II) -제 2 편: 주축모터 전류를 이용한 밀링의 황삭 가공 중 공구파손 검출-)

  • 김기대;이강희;주종남
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.5
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    • pp.110-119
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    • 1998
  • Dynamic cutting force variations in milling process were measured indirectly using spindle motor current. Magnitude of the spindle motor current is independent of cutting direction. Quasi-static sensitivity of the spindle motor current is higher than that of the feed motor current. Dynamic sensitivity of the spindle motor current is lower but cutting force was correctly represented by spindle RMS current in rough milling. In rough milling, chipping and tool fracture were well detected by the proposed tool fracture index using spindle motor current.

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Development of a multiplex PCR to identify Salmonella, Leptospira and Brucella species in tissue samples

  • Truong, Quang Lam;Yoon, Byung-Il;Hahn, Tae-Wook
    • Korean Journal of Veterinary Research
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    • v.52 no.2
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    • pp.75-82
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    • 2012
  • We have developed and optimized a multiplex polymerase chain reaction (mPCR) for simultaneous detection of Brucella, Salmonella and Leptospira with high sensitivity and specificity. Three pairs of oligonucleotide primers were designed to specifically amplify the targeted genes of Salmonella, Leptospira and Brucella species with sizes of 521, 408 and 223 bp, respectively. The mPCR did not produce any nonspecific amplification products when tested against 15 related species of bacteria. The sensitivity of the mPCR was 100 fg for Brucella and 1 pg for both Salmonella and Leptospira species. In the field application, kidney, liver and spleen were collected from wild rats and stray cats and examined by mPCR. The high specificity and sensitivity of this mPCR assay provide a valuable tool for diagnosis and for the simultaneous and rapid detection of three zoonotic bacteria that cause disease in both humans and animals. Therefore, this assay could be a useful alternative to the conventional method of culture and single PCR for the detection of each pathogen.

Efficient Fault Detection Method for a Degaussing Coil System Based on an Analytical Sensitivity Formula

  • Choi, Nak-Sun;Kim, Dong-Wook;Yang, Chang-Seob;Chung, Hyun-Ju;Kim, Heung-Geun;Kim, Dong-Hun
    • Journal of Magnetics
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    • v.18 no.2
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    • pp.135-141
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    • 2013
  • This paper proposes an efficient fault detection method for onboard degaussing coils which are installed to minimize underwater magnetic fields due to the ferromagnetic hull. To achieve this, the method basically uses field signals measured at specific magnetic treatment facilities instead of time-consuming numerical field solutions in a three-dimensional analysis space. In addition, an analytical design sensitivity formula and the linear property of degaussing coil fields is being exploited for detecting fault coil positions and assessing individual degaussing coil currents. Such peculiar features make it possible to yield fast and accurate results on the fault detection of degaussing coils. For foreseeable fault conditions, the proposed method is tested with a model ship equipped with 20 degaussing coils.

Imaging of Gastric Cancer Metabolism Using 18 F-FDG PET/CT

  • Yun, Mijin
    • Journal of Gastric Cancer
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    • v.14 no.1
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    • pp.1-6
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    • 2014
  • Aerobic glycolysis has been the most important hypothesis in cancer metabolism. It seems to be related to increased bioenergetic and biosynthetic needs in rapidly proliferating cancer cells. To this end, F-18 fluorodeoxyglucose (FDG), a glucose analog, became widely popular for the detection of malignancies combined with positron emission tomography/computed tomography (PET/CT). Although the potential roles of FDG PET/CT in primary tumor detection are not fully established, it seems to have a limited sensitivity in detecting early gastric cancer and mainly signet ring or non-solid types of advanced gastric cancer. In evaluating lymph node metastases, the location of lymph nodes and the degree of FDG uptake in primary tumors appear to be important factors affecting the diagnostic accuracy of PET/CT. In spite of the limited sensitivity, the high specificity of PET/CT for lymph node metastases may play an important role in changing the extent of lymphadenectomy or reducing futile laparotomies. For peritoneal metastases, PET/CT seems to have a poorer sensitivity but a better specificity than CT. The roles of PET/CT in the evaluation of other distant metastases are yet to be known. Studies including primary tumors with low FDG uptake or peritoneal recurrence seem suffer from poorer diagnostic performance for the detection of recurrent gastric cancer. There are only a few reports using FDG PET/CT to predict response to neoadjuvant or adjuvant chemotherapy. A complete metabolic response seems to be predictive of more favorable prognosis.

Damage Detection Using Finite Element Model Updating (유한요소 모델 개선기법을 이용한 손상추정)

  • Min, Cheon-Hong;Choi, Jong-Su;Hong, Sup;Kim, Hyung-Woo;Yeu, Tae-Kyeong
    • Journal of Ocean Engineering and Technology
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    • v.26 no.5
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    • pp.11-17
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    • 2012
  • In this study, a damage detection method that uses sensitivity-based finite (FE) element model updating with the natural frequency and zero frequency was proposed. The stiffness matrix for a structure was modified using the sensitivity-based FE model updating method. A sensitivity analysis was used to update the FE model, and the natural frequencies and zero frequencies were considered as target parameters to supplement the information on the vibration characteristics. The locations and values of the damages were estimated from the modified stiffness matrix. Several numerical examples were considered to verify the performance of the proposed method.

Value of Combined Detection of Serum CEA, CA72-4, CA19-9 and TSGF in the Diagnosis of Gastric Cancer

  • Yin, Li-Kui;Sun, Xue-Qing;Mou, Dong-Zhen
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3867-3870
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    • 2015
  • Background: To explore whether combined detection of serum tumor markers (CEA, CA72-4, CA19-9 and TSGF) improve the sensitivity and accuracy in the diagnosis of gastric cancer (GC). Materials and Methods: An automatic chemiluminescence immune analyzer with matched kits were used to determine the levels of serum CEA, CA72-4, CA19-9 and TSGF in 45 patients with gastric cancer (GC group), 40 patients with gastric benign diseases (GBD group) hospitalized in the same period and 30 healthy people undergoing a physical examination. The values of those 4 tumor markers in the diagnosis of gastric cancer was analyzed. Results: The levels of serum CEA, CA72-4, CA19-9 and TSGF of the GC group were higher than those of the GBD group and healthy examined people and the differences were significant (P<0.001). The area under receiver operating characteristic (ROC) curves for single detection of CEA, CA72-4, CA19-9 and TSGF in the diagnosis of GC was 0.833, 0.805, 0.810 and 0.839, respectively. The optimal cutoff values for these 4 indices were 2.36 ng/mL, 3.06 U/mL, 5.72 U/mL and 60.7 U/mL, respectively. With combined detection of tumor markers, the diagnostic power of those 4 indices was best, with an area under the ROC curve of 0.913 (95%CI 0.866~0.985), a sensitivity of 88.9% and a diagnostic accuracy of 90.4%. Conclusions: Combined detection of serum CEA, CA72-4, CA19-9 and TSGF increases the sensitivity and accuracy in diagnosis of GC, so it can be regarded as the important means for early diagnosis.

Simultaneous Detection of Listeria monocytogenes, Escherichia coli O157:H7, Bacillus cereus, Salmonella spp., and Staphylococcus aureus in Low-fatted Milk by Multiplex PCR

  • Kim, Ji-Hyun;Rhim, Seong-Ryul;Kim, Kee-Tae;Paik, Hyun-Dong;Lee, Joo-Yeon
    • Food Science of Animal Resources
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    • v.34 no.5
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    • pp.717-723
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    • 2014
  • A rapid and specific PCR assay for the simultaneous detection of Listeria monocytogenes, Escherichia coli O157:H7, Bacillus cereus, Salmonella spp., and Staphylococcus aureus in foods was developed to reduce the detection time and to increase sensitivity. Multiplex PCR developed in this study produced only actA, fliC, hbl, invA, ileS amplicons, but did not produce any non-specific amplicon. The primer sets successfully amplified the target genes in the multiplex PCR without any non-specific or additional bands on the other strains. The multiplex PCR assays also amplified some target genes from five pathogens, and multiplex amplification was obtained from as little as 1 pg of DNA. According to the results from the sensitivity evaluation, the multiplex PCR developed in this study detected 10 cells/mL of the pathogens inoculated in milk samples, respectively. The results suggested that multiplex PCR was an effective assay demonstrating high specificity for the simultaneous detection of five target pathogens in food system.

Measurement of Detection Efficiency of Plastic Track Detector to ${\alpha}-particle$ (고체비적검출기의 알파선 검출효율 측정에 관한 연구)

  • Park, Young-Woong;Yang, Hyun-Soo
    • Journal of Radiation Protection and Research
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    • v.21 no.3
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    • pp.167-173
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    • 1996
  • The calibration method for the detection efficiency of solid state track detector to alpha is presented, and the detection efficiency of CN-85 and LEXAN to alpha is measured by this method. The results are 97% and 57% in CN-85 and LEXAN, respectively. The reason for a better result in CN-85 in not only the high sensitivity but also the low energy dependency with comparing for LEXAN. The peak detection efficiency is 3MeV and 1.8MeV in CN-85 and LEXAN, respectively.

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Direct Triazine Herbicide Detection Using a Self-Assembled Photosynthetic Reaction Center from Purple Bacterium

  • Nakamura, Chikashi;Hasegawa, Miki;Shimada, Kazumi;Shirai, Makoto;Miyake, Jun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.6
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    • pp.413-417
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    • 2000
  • In this study, a direct detection system for triazine derivative herbicides was developed using the photosynthetic reaction center (RC) from the purple bacterium, Rhodobacter sphaeroides, and surface plasmon resonance (SPR) apparatus. The histidine-tagged RCs were immobilized on an SPR gold chip using nickel-nitrilotriacetic acid groups as a binder for one of the triazine herbicide, atrazine. The SPR responses were proportional to the sample concentrations of atrazine in the range 0.1-1 $\mu\textrm{g}$/mL. The sensitivity of the direct detection of atrazine using the RC-assembled sensor chip was higher than that using the antibody-immobilized chip. The other types of herbicides, DCMU or MCPP, were not detected with such high sensitivity. The results indicated the high binding selectivity of the RC complex.

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High sensitivity biosensor for mycotoxin detection based on conducting polymer supported electrochemically polymerized biopolymers

  • Dhayal, Marshal;Park, Gye-Choon;Park, Kyung-Hee;Gu, Hal-Bon
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.243.1-243.1
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    • 2010
  • Devices based on nanomaterials platforms are emerging as a powerful tool for ultrasensitive sensors for the direct detection of biological and chemical species. In this talk, we will report the preparation and the full characterization of electrochemical polymerization of biopolymers platforms and nano-structure formation for electrochemical detection of enzymatic activity and toxic compound in electrolyte for biosensor applications. Formation of an electroactive polymer film of two different compounds has been quantified by observing new redox peak at higher potentials in cyclic voltammogram measurements. RCT value of at various biopolymer concentration based hybrid films has been obtained from electrochemical impedance spectroscopy analysis and possible mechanism for formation of complexes during electrochemical polymerization on conducting substrates has been investigated. Biosensors developed based on these hybrid biopolymers have very high sensitivity.

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