• Title/Summary/Keyword: Ancillary Statistics

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THE DEVELOPMENT OF IR-BASED VISIBLE CHANNEL CALIBRATION USING DEEP CONVECTIVE CLOUDS

  • Ham, Seung-Hee;Sohn, Byung-Ju
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.430-432
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    • 2008
  • Visible channel calibration method using deep convective clouds (DCCs) is developed. The method has advantages that visible radiance is not sensitive to cloud optical thickness (COT) for deep convective clouds because visible radiance no longer increases when COT exceeds 100. Therefore, once DCCs are chosen appropriately, and then cloud optical properties can be assumed without operational ancillary data for the specification of cloud conditions in radiative transfer model. In this study, it is investigated whether IR measurements can be used for the selection of DCC targets. To construct appropriate threshold value for the selection of DCCs, the statistics of cloud optical properties are collected with MODIS measurements. When MODIS brightness temperature (TB) at 11 ${\mu}$ m is restricted to be less than 190 K, it is shown that more than 85% of selected pixels show COT ${\geq}$ 100. Moreover, effective radius ($r_e$) distribution shows a sharp peak around 20 ${\mu}m$. Based on those MODIS observations, cloud optical properties are assumed as COT = 200 and $r_e$ = 20 ${\mu}m$ for the simulation of MODIS visible (0.646 ${\mu}m$) band radiances over DCC targets.

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An Assessment of the Multiple Challenges Associated with Student's Access to Electronic Resources at a Public University Library in Ghana

  • Armah, Nesba Yaa Anima Adzobu;Cobblah, Mac-Anthony
    • International Journal of Knowledge Content Development & Technology
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    • v.11 no.1
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    • pp.65-84
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    • 2021
  • Our understanding of how barriers to access systematically varies with the compositional and contextual characteristics of users is incomplete. Using a public university library in Ghana, this study assessed the heterogeneous barriers or constraints students encounter in accessing electronic resources based on their demographic and contextual attributes. A descriptive survey design was adopted and structured questionnaires were administered randomly to 558 students in the four constituent colleges of the University of Cape Coast, Ghana. Data were collected and analysed using SPSS and descriptive statistics were generated. The results revealed that students faced six key challenges in accessing electronic information resources in the library namely delays in download of information, poor internet connectivity, and limited accessibility of university portal, inadequate computers in the library, poor lighting and limited ancillary services (on the spot printing facilities), with differences based on gender, academic level, and college affiliation. Only 24% males and 26% females had no challenges or problems with delays in download of electronic information. About three-fourth of all users had poor internet connectivity and complained about inadequate computers associated with accessing electronic resources. 40% percent of undergraduate students in the Colleges of Education Studies, Agriculture and Natural Sciences, and Humanities and Legal Studies each encountered four to six simultaneous challenges. Irrespective of gender, first year undergraduate students in all the four colleges were the least likely to report multiple challenges. This suggests the need for targeted and context-specific interventions to address the identified challenges.

Sex-Related Differences of EEG Coherences between Patients with Schizophrenia and Healthy Controls (조현병 환자와 건강한 대조군에서 성별에 따른 뇌파 동시성의 차이)

  • Jung, Hye Min;Lee, Yu Sang;Kim, Seongsu;Kim, Seongkyun;Jeong, Jaeseung;Oh, Jin-Seok;Lee, Seungyeoun;Kim, Bum Joon;Chang, Jae Seung
    • Korean Journal of Biological Psychiatry
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    • v.20 no.4
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    • pp.166-178
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    • 2013
  • Objectives Alteration of epigenetic effects of testosterone during early development was suggested as an ancillary mechanism for the genesis of schizophrenia. EEG coherence was thought to be a marker for cerebral laterality of which important determinant was testosterone during early development. We studied sex-related differences of EEG coherences between patients with schizophrenia and controls to examine the sex effects in the genesis of schizophrenia. Methods EEG was recorded in 35 patients with schizophrenia and 46 healthy controls in the eyes closed resting state. Pair-wise EEG coherences were calculated over delta, theta, alpha, beta and gamma frequency bands. To examine the differences of EEG coherence according to sex in each group, ANCOVA was performed using Statistical Analysis system (SAS, Ver 9.3) and R (Ver 2.15.2). Results Healthy control males showed more increased right intrahemispheric coherences than healthy control females in delta, theta, alpha and beta frequency bands. In patients with schizophrenia, this male dominant pattern in right intrahemispheric coherences was attenuated especially in alpha and beta bands. Healthy control females showed more increased interhemispheric coherences than healthy control males in delta, theta, beta and gamma frequency bands. In patients with schizophrenia, these female dominant patterns in interhemispheric coherences were attenuated especially in delta, theta, and beta bands, which were commonly observed in frontal to central areas. Conclusion Sex differences in resting EEG coherences were attenuated in schizophrenia patients. These results imply that sex-related aberrant cerebral lateralization might exist in patients with schizophrenia, which are partly due to sex hormones via epigenetic mechanisms.

Manual Liquid Based Cytology in Primary Screening for Cervical Cancer - a Cost Effective Preposition for Scarce Resource Settings

  • Nandini, N.M.;Nandish, S.M.;Pallavi, P.;Akshatha, S.K.;Chandrashekhar, A.P.;Anjali, S.;Dhar, Murali
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.3645-3651
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    • 2012
  • Conventional pap smear (CPS) examination has been the mainstay for early detection of cervical cancer. However, its widespread use has not been possible due to the inherent limitations, like presence of obscuring blood and inflammation, reducing its sensitivity considerably. Automated methods in use in developed countries may not be affordable in the developing countries due to paucity of resources. On the other hand, manual liquid based cytology (MLBC) is a technique that is cost effective and improves detection of precursor lesions and specimen adequacy. Therefore the aim of the study was to compare the utility of MLBC with that of CPS in cervical cancer screening. A prospective study of 100 cases through MLBC and CPS was conducted from October 2009 to July 2010, in a Medical College in India, by two independent pathologists and correlated with histopathology (22 cases). Morphological features as seen through MLBC and CPS were compared. Subsequently, all the cases were grouped based on cytological diagnosis according to two methods into 10 groups and a subjective comparison was made. In order to compare the validity of MLBC with CPS in case of major diagnoses, sensitivity and specificity of the two methods were estimated considering histological examination as the gold standard. Increased detection rate with MLBC was 150%. The concordance rate by LBC/histopathology v/s CPS/histopathology was also improved (86% vs 77%) The percentage agreement by the two methods was 68%. MLBC was more sensitive in diagnosis of LSIL and more specific in the diagnosis of inflammation. Thus, MLBC was found to be better than CPS in diagnosis of precursor lesions. It provided better morphology with increased detection of abnormalities and preservation of specimen for cell block and ancillary studies like immunocytochemistry and HPV detection. Therefore, it can be used as alternative strategy for cervical cancer prevention in limited resource settings.

Extraction of Gravity-typed Accessibility Index using Remotely Sensed Imagery and Its Application (위성영상정보의 중력모델기반 접근성지수 추출연계 및 적용)

  • Lee, Kiwon;Oh, Se Gyong;Lee, Bong Gyu
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.3
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    • pp.61-72
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    • 2003
  • Recently, demands with practical applications using high resolution imagery are increasing, according to addressing new sensor data. Since late 1990s, attempts for application to transportation problems of satellite imagery data have been intensively carried out in US, and these kinds of studies are being categorized into the name of RS-T(remote sensing in transportation). Further, this study is also linked with GIS-T(GIS for transportation), being in the matured stage, and then it contributes to wide uses of remotely sensed imagery. In this study, RS-T is briefly summarized. Later, in order to apply urban transportation analysis with satellite imagery as ancillary data, implementation, as prototyped extension program, for extraction of gravity-typed accessibility indices of transportation geography is performed in the ArcView-GIS environment. It is thought that applied results by two models among implemented models in this study can be utilized to characterize transportation accessibility in a region and to apply as useful statistics related to urban transportation status for regional transportation planning, if time series data are used.

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