• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.11
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• pp.587-595
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• 2015

In this study, fault symptoms were simulated and analyzed for a single-effect absorption chiller. The fault patterns of fault detection parameters were tabulated using the fault symptom simulation results. Fault detection and diagnosis by a process history-based method were performed for the in-situ experiment of a single-effect absorption chiller. Simulated fault modes for the in-situ experimental study are the decreases in cooling water and chilled water mass flow rates. Five no-fault reference models for fault detection of a single-effect absorption chiller were developed using fault-free steady-state data. A sensitivity analysis of fault detection using the normalized distance method was carried out with respect to fault progress. When mass flow rates of the cooling and chilled water decrease by more than 19.3% and 17.8%, respectively, the fault can be detected using the normalized distance method, and COP reductions are 6.8% and 4.7%, respectively, compared with normal operation performance. The pattern recognition method for fault diagnosis of a single-effect absorption chiller was found to indicate each failure mode accurately.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2771-2776
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• 2014

Background: Breast cancer screening and higher quality mammography have resulted in an increase in the diagnosis of ductal carcinoma in situ worldwide. We compared the incidence and other factors in our cases of ductal carcinoma in situ between two recent decades. Materials and Methods: Medical records of cases of ductal carcinoma in situ who had been admitted to the surgery wards of the Cancer Institute of Tehran, Iran were evaluated from March 1993 to March 2003 as phase 1, and from April 2003 to April 2013 as phase 2. Results: Ratio of ductal carcinoma in situ to overall breast cancer was 1.27 and 3.93 in phases 1 and 2, respectively. Rates of excisional or incisional biopsies versus core needle biopsies and clinically versus mammographically detected cases as well as median size of tumors dropped between the 2 phases while a substantial rise in the number of patients attending for screening was seen in this time period. Surgical treatments followed a trend from modified radical mastectomy and axillary lymphatic dissection toward breast conserving surgery and sentinel node dissection or no axillary intervention. Conclusions: Our study shows a considerable trend toward earlier detection of breast cancer and evolution of treatment strategies toward standard less invasive surgery of DCIS in Iran.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.3
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• pp.221-230
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• 2002

In this study, in-situ performance test of an air source heat pump which has a arted capacity of 10 RT is carried out. Since test conditions, such as indoor and outdoor air conditions cannot be controlled to satisfy the standard test conditions, experiments are done with the inlet air conditions as they exist. To estimate the performance for other conditions, he heat pump is modeled with a small number of selected parameters. The values of the parameters are determined from the few measurements measured on-site during normal operation. A simulation program is developed to calculate cooling capacity and power consumption t any other operating conditions. The simulation results are in good agreement with the experiment. This study provides a method of an on-site performance diagnosis of an air source heat pump.

• Journal of the Korean Electrochemical Society
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• v.12 no.4
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• pp.329-334
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• 2009

This study is to develop a fuel cell system applicable to an in situ NMR (Nuclear magnetic resonance) diagnosis. The in situ NMR can be used in real time monitoring of various reactions occurring in the fuel cell, such as oxidation of fuel, reduction of oxygen, transport phenomena, and component degradation. The fuel cell for this purpose is, however, to be operated in a specifically designed tubular shape toroid cavity detector (TCD), which constrains the fuel cell to have a tubular shape. This may cause difficulties in effective mass transport of reactants/products and uniform distribution of assembly pressure. Therefore, a new flow field designed in a particular way is necessary to enhance the mass transport in the tubular fuel cell. In this study, a tubular-shaped close-type flow field made of non-magnetic material is developed. With this flow field, oxygen is effectively delivered to the cathode surface and the produced water is readily removed from the membrane-electrode assembly to prevent flooding. The resulting DMFC (direct methanol fuel cell) outperforms the open-type flow field and exhibits $36\;mW/cm^2$ even at room temperature.

• Journal of Aquaculture
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• v.18 no.3
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• pp.207-214
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• 2005

We report on the diagnosis, pathology, and taxonomy of Perkinsus sp. infection in Manila clams (Ruditapes philippinarum) from Korean waters. Amplimers were designed from internal portions of the non-transcribed spacer (NTS) of P. atlanticus for molecular diagnosis of Perkinsus infection. PCR-based identification methods and an in situ hybridization assay were developed for detection of Perkinsus sp. in live tissues as well as in histological preparations. Hybridization signals were observed around the nucleus of trophozoites. Positive results from PCR and in situ hybridization indicated that Korean Perkinsus sp. is genetically identical with P. atlanticus reported in Europe, which is currently synonymous with P. olseni reported from Australia. Microscopic morphological features of different lift stages of Perkinsus sp. appeared very similar to those of P. atlanticus. Severely infected clams often exhibited white nodules on their mantles and gills as a consequence of inflammation. In lightly to moderately infected clams, Perkinsus sp. was mainly found in gill tissues, whereas the protozoan parasites were found in digestive tracts, gonadal tissues, and foot tissues of heavily infected clams. It is likely that the gills are the portal of the infection and that P. olseni spreads to other tissues as the infection advances. In conclusion, by considering the taxonomic priority of P. olseni, Korean Perkinsus sp. is accepted as P. olseni. P. olseni appears to be common on tidal flats on the western and southern Korean coasts and is considered to be a pathogen capable of causing mass mortality of clams.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.29 no.2
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• pp.98-102
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• 2018

Background and Objectives : Detection of vascular abnormalities in vocal cord (VC) leukoplakia is important for the diagnosis of neoplastic change of the mucosa. The aim of this study was to investigate the value of i-scan in the differential diagnosis of VC leukoplakia based on visualization of abnormal vascular features. Material and Methods : Fifty-two patients with leukoplakia were enrolled in the study. Images of their larynx obtained using conventional white light endoscopy and an i-scan-enhanced endoscopy (Pentax DEFINA EPK-3000 Video Processors, with Pentax VNLJ10) were reviewed. The microvascular features of the lesions and vascular changes were analyzed and the results were compared with the histopathologic diagnosis. Results : Among the 52 leukoplakia patients, 7 (13.5%) patients had squamous hyperplasia, 10 (19.3%) mild dysplasia, 2 (3.8%) moderate dysplasia, 14 (26.9%) severe dysplasia, 4 (7.7%) carcinoma in situ, and 15 (28.8%) invasive squamous cell carcinoma on histopathologic examination. Using i-scan-enhanced endoscopy, abnormal vascular change with neoplastic neoangiogenesis was detected in most cases of malignant VC lesion [severe dysplasia : 9/14 (64.3%), carcinoma in situ: 2/4 (50.0%), and invasive squamous cell carcinoma : 11/15 (73.4%)]. Conclusion : i-scan-enhanced endoscopy is a useful optical technique for the diagnosis of VC leukoplakia. Our results suggest that i-scan may be a promising diagnostic tool in the early detection of laryngeal cancer.

• Pediatric Infection and Vaccine
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• v.3 no.2
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• pp.200-206
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• 1996

Virus associated hemophagocytic syndrome(VAHS), a class II histiocytosis syndrome, is characterized by high fever, liver dysfunction, coagulation abnormalities, and generalized histiocytic proliferation with marked hemophagocytosis in bone marrow and lymph nodes. VAHS is associated with several viral infections including Epstein Barr virus which has a relatively high mortality rate. We report a fatal case of Epstein Barr virus associated hemophagocytic syndrome and its diagnosis by mRNA in situ hybridization and polymerase chain reaction. A brief review of related literaure is also presented.

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.57-62
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• 2001

Recently various molecular diagnostic techniques have been used to identify rabbit hemorrhagic disease virus (RHDV), a causative agent responsible for acute hepatitis and disseminated intravascular coagulation in rabbit. But they were hard to perform and time consuming. To detect RHDV in a rapid and easy way, we developed biotinylated oligonucleotide probe within ORF 1 region encoding the polyprotein of RHDV in formalin-fixed and paraffin-embedded tissues from various tissues of 20 rabbits naturally infected with RHDV, Our in situ hybridization (ISH) was quickly carried out within two hours by MicroProbe capillary action system. The ISH produced a positive reaction in liver, kidney and lung. In conclusion, ISH with a biotintlated oligonucleotide probe provided a useful diagnostic method for detecting RHDV.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.327-333
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• 1994

The purpose of this study was to establish a rapid diagnostic method detecting Aujeszky's disease virus (ADV) DNA in the cultured cell monolayers (PK-15) and tissue sections of ADV(NYJ-1-87)-infected rats and pigs by in situ hybridization(ISH). Detection of specific ADV-DNA in infected cells was conducted by radiolabeled ISH method using $^{32}P-labeled $ DNA probe (BamH1 7 fragment) which contains a 6.3 Kb ADV-DNA insert. Where ADV-DNA was detected by radiolabeled ISH, the deposition of black photographic grains occurred in the nuclei and the cytoplasms of ADV-infected cells. Positive hybridization signal was often observed in the spinal trigerminal nucleus of the pons, the nucleus of the trigerminal ganglion neuron and the epithelial cells of tonsillar crypts. The results suggested that ISH is considered as a highly sensitive and reliable tool for confirmative diagnosis of this viral disease.

• Journal of Power Electronics
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• v.16 no.2
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• pp.695-703
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• 2016

A fuel cell power conditioning system for online diagnosis and load leveling under the condition of varying load is developed in this study. The proposed system comprises a unidirectional boost converter and a bidirectional buck-boost converter with a battery. The system operates in two different modes. In normal mode, the bidirectional converter is utilized for load leveling; in diagnostic mode, it is utilized to control load voltage while the boost converter generates perturbation current to implement the online diagnosis function through in-situ electrochemical impedance spectroscopy (EIS). The proposed method can perform EIS for a fuel cell under varying-load conditions with no influence on the load. The validity and feasibility of the proposed system are verified by experiments, and the design procedure of the proposed system is detailed.