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Sacral Acupuncture for Lower Urinary Tract Symptoms: A Systematic Review of Randomized Controlled Trials

  • Park, Jiwon;Chun, Se-Eun;Park, Min-Cheol;Jo, Eun-Heui
    • Journal of Acupuncture Research
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    • v.39 no.1
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    • pp.1-9
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    • 2022
  • Lower urinary tract symptoms (LUTS) associated with storage, voiding, and post-micturition reduce quality of life and cause mental health problems. In traditional medicine, Baliao points have been empirically used to treat urinary system diseases. In this review, randomized controlled trials (RCTs) using sacral acupuncture on Baliao points with sham treatment, other remedies, or other acupoints were retrieved from 8 electronic databases up to June 2021. Sixteen RCTs met the inclusion criteria. The quality of the included studies was assessed using a risk-of-bias (ROB) tool. Most of the evaluation indicators used in the included RCTs showed that sacral acupuncture had a significant therapeutic effect compared with the sham control intervention groups, and other remedies. However, all studies using acupoints (other than the Baliao points) as a control intervention had a "high" ROB and only reported secondary processed information, making it difficult to evaluate the efficacy of sacral acupuncture treatment for LUTS. No serious adverse effects were reported for sacral acupuncture, and only a low number of minor side effects were observed. These results suggest that sacral acupuncture could be considered as an alternative to existing treatments, with the added benefit of low cost. Large-scale, long-term RCTs are required in the future.

A study on hyperparameters optimization of LSTM model for improving flood level prediction accuracy (하천 홍수위 예측 정확도 개선을 위한 LSTM 모형의 하이퍼파라미터 최적화 연구)

  • Jaewon Jung;Sooyoung Kim;Hyung-Jun Kim;Kwang Seok Yoon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.415-415
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    • 2023
  • 홍수는 일반적으로 많은 피해와 인명 손실을 초래하는 자연재해 중 하나로, 홍수위 예측은 이를 방지하고 대처하는 데 중요한 역할을 한다. 최근 기계학습 기술을 이용하여 홍수위 예측 모델을 개발하고자 하는 연구가 많이 진행되고 있다. 특히, LSTM(long short-term memory) 모형은 시계열 예측에 대해 검증된 모형으로 홍수위 예측 연구에도 활발하게 적용되고 있다. 하지만 기계학습 모델의 학습 성능은 하이퍼파라미터의 값에 영향을 크게 받을 수 있으며, 특히 집중호우로 인해 수위가 급변하는 경우에는 과거 시계열 자료에 영향을 받는 LSTM 모형의 예측 성능이 오히려 낮게 나타날 수 있다. 따라서 본 연구에서는 홍수위 예측시 LSTM 모형의 예측 성능을 향상시킬 수 있는 세부 하이퍼파라미터 값을 분석하여 최적의 하이퍼파라미터 조합을 제안하고자 한다. 이를 위해 하이퍼파라미터 조정을 위한 자동화 도구인 W&B(Weights&Bias)의 Sweep 기능을 적용하고자 한다. 본 연구를 통해 LSTM 모형을 적용한 홍수위 예측의 정확도를 향상시키는 데에 기여할 수 있을 것으로 기대된다.

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Prediction of sediment flow to Pleikrong reservoir due to the impact of climate change

  • Xuan Khanh Do;ThuNgaLe;ThuHienNguyen
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.38-38
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    • 2023
  • Pleikrong reservoir with a concrete gravity dam that impound more than 1 billion cubic meter storage volume is one of the largest reservoir in Central Highland of Vietnam. Sedimentation is a major problem in this area and it becomes more severe due to the effect of climate change. Over time, it gradually reduces the reservoir storage capacity affecting to the reliability of water and power supply. This study aims to integrate the soil and water assessment tool (SWAT) model with 14 bias-corrected GCM/RCM models under two emissions scenarios, representative concentration pathway (RCP) 4.5 and 8.5 to estimate sediment inflow to Pleikrong reservoir in the long term period. The result indicated that the simulated total amount of sediment deposited in the reservoir from 2010 to 2018 was approximately 39 mil m3 which is a 17% underestimate compared with the observed value of 47 mil m3. The results also show the reduction in reservoir storage capacity due to sedimentation ranges from 25% to 62% by 2050, depending on the different climate change models. The reservoir reduced storage volume's rate in considering the impact of climate change is much faster than in the case of no climate change. The outcomes of this study will be helpful for a sustainable and climate-resilient plan of sediment management for the Pleikrongreservoir.

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THE VALIDITY OF HEALTH ASSESSMENTS: RESOLVING SOME RECENT DIFFERENCES

  • Hyland Michael E.
    • 대한예방의학회:학술대회논문집
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    • 1994.02b
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    • pp.137-141
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    • 1994
  • The purpose of this paper is to examine what is meant by a ralid measure of health. Guyatt, Kirshner and Jaeschke propose that health tests should be designed so as to have one of several kinds of validity: 'longitudinal construct validity' for those which are used for longitudinal research designs, and 'cross-sectional construct validity' for those which are used for cross-sectional designs. Williams and Naylor argue that this approach to test classification and validation confuses what a test purports to measure with the purpose for which it is used, and that some tests have multiple uses. A review of the meanings of validity in the psychologica test literature shows that both sets of authors use the term validity in an idiosyncratic way. Although the use of a test (evaluated by content validity) should not be conflated with whether the test actually measures a specified construct (evaluated by construct validity);' if health is actually made up of several constructs (as suggested in Hyland's interactional model) then there may be an association between types of construct and types of purpose. Evidence is reviewed that people make several, independent judgements about their health: cognitive perceptions of health problems are likely to be more sensitive to change in a longitudinal research design. whereas emotional evaluations of health provide less bias in cross-sectional designs. Thus. a classification of health measures in terms of the purpose of the test may parallel a classification in terms of what tests purport to measure.

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Improvement in Regional-Scale Seasonal Prediction of Agro-Climatic Indices Based on Surface Air Temperature over the United States Using Empirical Quantile Mapping (경험적 분위사상법을 이용한 미국 지표 기온 기반 농업기후지수의 지역 규모 계절 예측성 개선)

  • Chan-Yeong, Song;Joong-Bae, Ahn;Kyung-Do, Lee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.201-217
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    • 2022
  • The United States is one of the largest producers of major crops such as wheat, maize, and soybeans, and is a major exporter of these crops. Therefore, it is important to estimate the crop production of the country in advance based on reliable long- term weather forecast information for stable crops supply and demand in Korea. The purpose of this study is to improve the seasonal predictability of the agro-climatic indices over the United States by using regional-scale daily temperature. For long-term numerical weather prediction, a dynamical downscaling is performed using Weather Research and Forecasting (WRF) model, a regional climate model. As the initial and lateral boundary conditions of WRF, the global hourly prediction data obtained from the Pusan National University Coupled General Circulation Model (PNU CGCM) are used. The integration of WRF is performed for 22 years (2000-2021) for period from June to December of each year. The empirical quantile mapping, one of the bias correction methods, is applied to the timeseries of downscaled daily mean, minimum, and maximum temperature to correct the model biases. The uncorrected and corrected datasets are referred WRF_UC and WRF_C, respectively in this study. The daily minimum (maximum) temperature obtained from WRF_UC presents warm (cold) biases over most of the United States, which can be attributed to the underestimated the low (high) temperature range. The results show that WRF_C simulates closer to the observed temperature than WRF_UC, which lead to improve the long- term predictability of the temperature- based agro-climatic indices.

A Study for establishment of soil moisture station in mountain terrain (1): the representative analysis of soil moisture for construction of Cosmic-ray verification system (산악 지형에서의 토양수분 관측소 구축을 위한 연구(1): Cosmic-ray 검증시스템 구축을 위한 토양수분량 대표성 분석 연구)

  • Kim, Kiyoung;Jung, Sungwon;Lee, Yeongil
    • Journal of Korea Water Resources Association
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    • v.52 no.1
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    • pp.51-60
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    • 2019
  • The major purpose of this study is to construct an in-situ soil moisture verification network employing Frequency Domain Reflectometry (FDR) sensors for Cosmic-ray soil moisture observation system operation as well as long-term field-scale soil moisture monitoring. The test bed of Cosmic-ray and FDR verification network system was established at the Sulma Catchment, in connection with the existing instrumentations for integrated data provision of various hydrologic variables. This test bed includes one Cosmic-ray Neutron Probe (CRNP) and ten FDR stations with four different measurement depths (10 cm, 20 cm, 30 cm, and 40 cm) at each station, and has been operating since July 2018. Furthermore, to assess the reliability of the in-situ verification network, the volumetric water content data measured by FDR sensors were compared to those calculated through the core sampling method. The evaluation results of FDR sensors- measured soil moisture against sampling method during the study period indicated a reasonable agreement, with average values of $bias=-0.03m^3/m^3$ and RMSE $0.03m^3/m^3$, revealing that this FDR network is adequate to provide long-term reliable field-scale soil moisture monitoring at Sulmacheon basin. In addition, soil moisture time series observed at all FDR stations during the study period generally respond well to the rainfall events; and at some locations, the characteristics of rainfall water intercepted by canopy were also identified. The Temporal Stability Analysis (TSA) was performed for all FDR stations located within the CRNP footprint at each measurement depth to determine the representative locations for field-average soil moisture at different soil profiles of the verification network. The TSA results showed that superior performances were obtained at FDR 5 for 10 cm depth, FDR 8 for 20 cm depth, FDR2 for 30 cm depth, and FDR1 for 40 cm depth, respectively; demonstrating that those aforementioned stations can be regarded as temporal stable locations to represent field mean soil moisture measurements at their corresponding measurement depths. Although the limit on study duration has been presented, the analysis results of this study can provide useful knowledge on soil moisture variability and stability at the test bed, as well as supporting the utilization of the Cosmic-ray observation system for long-term field-scale soil moisture monitoring.

An Adjustment of Cloud Factors for Continuity and Consistency of Insolation Estimations between GOES-9 and MTSAT-1R (GOES-9과 MTSAT-1R 위성 간의 일사량 산출의 연속성과 일관성 확보를 위한 구름 감쇠 계수의 조정)

  • Kim, In-Hwan;Han, Kyung-Soo;Yeom, Jong-Min
    • Korean Journal of Remote Sensing
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    • v.28 no.1
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    • pp.69-77
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    • 2012
  • Surface insolation is one of the major indicators for climate research over the Earth system. For the climate research, long-term data and wide range of spatial coverage from the data observed by two or more of satellites of the same orbit are needed. It is important to improve the continuity and consistency of the derived products, such as surface insolation, from different satellites. In this study, surface insolations based on Geostationary Operational Environmental Satellite (GOES-9) and Multi-functional Transport Satellites (MTSAT-1R) were compared during overlap period using physical model of insolation to find ways to improve the consistency and continuity between two satellites through comparison of each channel data and ground observation data. The thermal infrared brightness temperature of two satellites show a relatively good agreement between two satellites : rootmean square error (RMSE)=5.595 Kelvin; Bias=2.065 Kelvin. Whereas, visible channels shown a quite different values, but it distributed similar tendency. And the surface insolations from two satellites are different from the ground observation data. To improve the quality of retrieved insolations, we have reproduced surface insolation of each satellite through adjustment of the Cloud Factor, and the Cloud Factor for GOES-9 satellite is modified based on the analysis result of difference channel data. As a result, the insolations estimated from GOES-9 for cloudy conditions show good agreement with MTSAT-1R and ground observation : RMSE=$83.439W\;m^{-2}$ Bias=$27.296W\;m^{-2}$. The result improved accuracy confirms that the modification of Cloud Factor for GOES-9 can improve the continuity and consistency of the insolations derived from two or more satellites.

The GOCI-II Early Mission Ocean Color Products in Comparison with the GOCI Toward the Continuity of Chollian Multi-satellite Ocean Color Data (천리안해양위성 연속자료 구축을 위한 GOCI-II 임무 초기 주요 해색산출물의 GOCI 자료와 비교 분석)

  • Park, Myung-Sook;Jung, Hahn Chul;Lee, Seonju;Ahn, Jae-Hyun;Bae, Sujung;Choi, Jong-Kuk
    • Korean Journal of Remote Sensing
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    • v.37 no.5_2
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    • pp.1281-1293
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    • 2021
  • The recent launch of the GOCI-II enables South Korea to have the world's first capability in deriving the ocean color data at geostationary satellite orbit for about 20 years. It is necessary to develop a consistent long-term ocean color time-series spanning GOCI to GOCI-II mission and improve the accuracy through validation using in situ data. To assess the GOCI-II's early mission performance, the objective of this study is to compare the GOCI-II Chlorophyll-a concentration (Chl-a), Colored Dissolved Organic Matter (CDOM), and remote sensing reflectances (Rrs) through comparison with the GOCI data. Overall, the distribution of GOCI-II Chl-a corresponds with that of the GOCI over the Yellow Sea, Korea Strait, and the Ulleung Basin. In particular, a smaller RMSE value (0.07) between GOCI and GOCI-II over the summer Ulleung Basin confirms the GOCI-II data's reliability. However, despite the excellent correlation, the GOCI-II tends to overestimate Chl-a than the GOCI over the Yellow Sea and Korea Strait. The similar over-estimation bias of the GOCI-II is also notable in CDOM. Whereas no significant bias or error is found for Rrs at 490 nm and 550 nm (RMSE~0), the underestimation of Rrs at 443 nm contributes to the overestimation of GOCI-II Chl-a and CDOM over the Yellow Sea and the Korea Strait. Also, we show over-estimation of GOCI-II Rrs at 660 nm relative to GOCI to cause a possible bias in Total suspended sediment. In conclusion, this study confirms the initial reliability of the GOCI-II ocean color products, and upcoming update of GOCI-II radiometric calibration will lessen the inconsistency between GOCI and GOCI-II ocean color products.

A Study on the Loan Structure and Profitability of Banks (은행의 대출 구조와 수익성 변동에 관한 연구)

  • Kang, Myoung-seok;Sin, Jeong-hun
    • Journal of Venture Innovation
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    • v.2 no.2
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    • pp.117-126
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    • 2019
  • This study conducted correlation analysis and multiple regression analysis using financial statements, loan structure, ROA and ROA volatility of domestic commercial banks, regional banks and special banks for the past five years (2012 ~ 2016). The result is as follows. First, as a result of correlation analysis, bank's ROA is positively related to household loans and SME loans, but it is negatively correlated with the ratio of loans to large companies, sector bias, and loan loss provision ratio. Second, ROA volatility was negatively related to household loans and SME loans, but it was positively correlated with large corporate loans, sector bias ratio, and loan loss provision ratio. Third, as a result of the regression analysis, the variables that have a statistically significant effect on the ROA volatility of banks were household loans, SME loans, and large enterprise loans. From these empirical results, special banks with high volatility in profits need to diversify loan types and sectors in order to achieve business performance outside of policy finance. and Especially, Suhyup Bank and Nonghyup Bank, which have a large commercial role, have a large size per unit by focusing on short-term profit and Rather than focusing on large companies or large loans that are easy to obtain financial information, it is necessary to focus management capabilities on household loans and SME loans by developing capabilities such as screening techniques.

A Study of Global Ocean Data Assimilation using VAF (VAF 변분법을 이용한 전구 해양자료 동화 연구)

  • Ahn, Joong-Bae;Yoon, Yong-Hoon;Cho, Eek-Hyun;Oh, He-Ram
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.69-78
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    • 2005
  • ARCO and TAO data which supply three dimensional global ocean information are assimilated to the background field from a general circulation model, MOM3. Using a variational Analysis using Filter (VAF), which is a spatial variational filter designed to reduce computational time and space efficiently and economically, observed ARGO and TAO data are assimilated to the OGCM-generated background sea temperature for the generation of initial condition of the model. For the assessment of the assimilation impact, a comparative experiment has been done by integrating the model from different intial conditions: one from ARGO-, TAO-data assimilated initial condition and the other from background state without assimilation. The assimilated analysis field not only depicts major oceanic features more realistically but also reduces several systematic model bias that appear in every current OGCMs experiments. From the 10-month of model integrations with and without assimilated initial conditions, it is found that the major assimilated characteristics in sea temperature appeared in the initial field remain persistently throughout the integration. Such implies that the assimilated characteristics of the reduced sea temperature bias is to last in the integration without rapid restoration to the non-assimilated OGCM integration state by dispersing mass field in the form of internal gravity waves. From our analysis, it is concluded that the data assimilation method adapted in this study to MOM3 is reasonable and applicable with dynamical consistency. The success in generating initial condition with ARGO and TAO data assimilation has significant implication upon the prediction of the long-term climate and weather using ocean-atmosphere coupled model.