• 오토저널
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• 제14권6호
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• pp.60-66
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• 1992

This study describes a theoretical analysis for the wall temperature of ceramic filter trap and pressures of inlet and outlet channel in the filter trap. In this study, the maximum wall temperature through filter trap length with time during the regeneration period showed a tendency moving from forward to backward. The pressure change of filter trap increased at the initial combustion but decreased with the combustion to be activated. So the pressure difference between initial and end regeneration at the inlet channel showed about 2kPa. The thermal regeneration period of this filter trap in the theoretical analysis showed about 200seconds in which the wall temperature was similar to the case of initial condition and the pressure showed about 1 kPa.

• International Journal of Internet, Broadcasting and Communication
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• 제16권2호
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• pp.193-202
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• 2024

As companies specialize, they use more modern applications, but they still rely on legacy systems and data access is limited by data silos. In this paper, we propose the Fabricator system, a design system for metadata based on Data Fabric that plays a key role in the data orchestration layer consisting of three layers: Sources Engine, Workload Builder, and Data Fabric Ingestion, thereby achieving meaningful integration of data and information. Provides useful insights to users through conversion. This allows businesses to efficiently access and utilize data, overcoming the limitations of legacy systems.

• Safety and Health at Work
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• 제11권2호
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• pp.136-142
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• 2020

Background: Rheumatoid arthritis (RA) is an autoimmune disease with systemic inflammatory arthritis. This meta-analysis was conducted to examine the association between occupational exposure to silica and the risk of developing RA among different workers. Methods: In this meta-analysis, we searched relevant published studies using major electronic databases including Scopus, PubMed, ISI Web of Science, and Google Scholar search engine up to October 2019, and the references of retrieved articles were also checked for further possible sources. A random-effects model was used to account for heterogeneity among the results of the studies using the pooled odds ratios (ORs) and their 95% confidence intervals (CIs). The Q-statistic and I² tests were calculated to assess heterogeneity between the studies. Results: The pooled calculation of OR indicated a significant association between occupational exposure to silica and risk of developing RA among different workers (OR = 2.59, 95% CI = 1.73 to 3.45). In addition, the pooled estimates of OR in smokers were statistically significant (OR = 2.49, 95% CI = 1.13 to 3.86). Conclusions: The findings of the present study reveal that occupational exposure to silica may be associated with increased risk of developing RA.

• 대한한방내과학회지
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• 제42권3호
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• pp.385-402
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• 2021

Objective: This study confirms the safety and efficacy of Banhasasim-tang (BST) against cough through systematic review and meta-analysis. Methods: PubMed, Cochrane, ScienceDirect, Wiley online library, OASIS, KISS, NDSL, RISS, Science and Technology Society Village, DBpia, CNKI, J-STAGE, and CiNii were used as search engines. The search period was from the start of search engine support to June 30. 2020. And search language was not limited. Cochrane's risk of bias (RoB) tool was used to evaluate the quality of the studies. A meta-analysis of the total effective rate (TER), cough symptom score, and spirometry results was performed using the Review Manager program. Results: 6 studies were finally selected. The group using BST showed significant symptom relief, as the odds ratio (OR) value of TER was 5.56 times higher (95% CI: 3.50, 8.82, P<0.0001) compared to the control groups. The reported adverse effects did not occur in the intervention group. In addition, the cough symptom score and spirometry results showed that BST was more effective than Western medicine alone. Conclusion: BST can be expected to relieve cough, and it can be applied to chronic cough that is not treated with existing treatments. However, due to the low quality of the selected articles, additional high-quality RCTs will be required in the future.

• 드라이브 ㆍ 컨트롤
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• 제17권2호
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• pp.9-18
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• 2020

The purpose of this study was to analyze the effect of the soil cone index (CI) on the tractor work load. A load measurement system was constructed for measuring the field data. The field sites were divided into grids (3×3 m), and the cone index was measured at the center of each grid. The work load measured through the plow tillage was matched with the soil cone index. The matched data were grouped at 600 kPa intervals based on the cone index. The work load according to the cone index was analyzed for engine, axle, and traction load, respectively. The results showed that when the cone index increased, engine torque decreased by up to 9%, and the engine rotational speed and brake-specific fuel consumption increased by up to 5% and 3%, respectively. As the cone index increased, the traction and tillage depth were inversely proportional to the cone index, decreasing 7% and 18%, respectively and the traction and tillage depth were directly proportional to the cone index, increasing 13% and 12%, respectively. Thus, it was found that the cone index had a major influence on the engine, axle, and traction loads of the tractor.

• 대한기계학회논문집B
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• 제35권1호
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• pp.67-73
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• 2011

본 연구는 DME-바이오디젤 혼합연료의 분무 및 연소, 배기 특성을 바이오디젤과 비교한 실험적 연구이며 실험연료는 바이오디젤 (BD100)과 중량 기준으로 DME를 20% 혼합한 DME-바이오디젤 혼합연료 (B-DME20)이다. 거시적 분무 특성을 연구하기 위하여 분무 이미지로부터 분무도달거리, 분무각을 측정하였으며, 연소 및 배기 특성은 단기통 직접 분사식 압축착화 기관을 이용하여 분석하였다. 실험결과 바이오디젤과 DME-바이오디젤 혼합연료는 분사율에서는 큰 차이가 없었지만 혼합연료의 경우에 착화지연기간이 짧고 연소압력이 높았으며soot 배출물이 현저하게 줄어들었다.

• 한국자동차공학회논문집
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• 제21권3호
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• pp.82-87
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• 2013

In this work, the 1L grade integrated metal DOC/DPF filter that can install in engine manifold position was developed to investigate the effect of platinum-coating amount of filter on the improvement of filter activation temperature and reduction of particulate matter (PM). This filter was installed in 2.9L CI engine which meets the EURO-4 emission regulation. Tests for PM reduction efficiency of filter were conducted under ND-13 mode with full-load test condition. It was revealed that the time to reach the activation temperature of metal filter ($280^{\circ}C$) was shorter as the amount of platinum-coating increased. This short activation time can be helpful for the reduction of CO and HC emissions during cold start condition. At the same time, PM reduced as the coating amount increased. The reduction percentage of $DOC_{40}$, $DOC_{20}$, and $DOC_0$ were 96.7% (2.34 mg/kW'h), 95.1% (3.47 mg/kW'h), and 94.5% (3.69 mg/kW'h) compared to previous result (71.4 mg/kW'h), respectively.

• 전자공학회논문지CI
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• 제49권2호
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• pp.44-52
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• 2012

본 논문은 검색 질의어 단어 입력 시에 드러나지 않은 쿼리 단어들을 가시화함으로써, 검색 주체의 의도 구조를 선택할 수있게 하며, 탐색 효율을 제고하도록 제안한다. 검색 질의어를 입력할 때 검색 의도를 파악한다면 효과적인 검색 서비스가 가능할 것이다. 이렇게 하기 위하여, 의도 구조와 요소를 설정함과 아울러 쿼리 단어의 생략된 관계에 해당하는 단어를 복원하여 가시화하는 과정이 필요하다. 관련된 연구들을 검토하며, 검색 의도 구조를 정의하고, 쿼리 단어의 가시화를 위한 방법과 의도 구조에 적합한 쿼리 단어를 확장 생성하는 과정을 보인다. 이 과정에서 의도 구조의 여러 계층 중 하나를 쿼리 단어 범위로 할당하는 예제와 실험을 수행하였다. 탐색 효율 상승의 검색결과와 탐색효율 하락의 검색결과를 분석하였다. 향후 연구로는 의도 결절을 확장하여 구성 요소를 학습할 수 있도록 자동화하는 연구가 필요하다.

• 전자공학회논문지CI
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• 제40권1호
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• pp.74-81
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• 2003

본 연구에서는 음성인식 엔진과 데이터베이스에 필요한 메모리 규모를 최소화시킨 실시간 임베디드 음성인식 시스템을 구현하였다. 실험을 위해 PCS 전화기에서 사용하는 40가지의 명령어와 10개의 숫자음으로 구성된 단어 목록을 만들고, 이들 단어들을 남,여 화자가 발성하여 음성 시료를 구했다. 채록된 음성을 대상으로 창크기 256표본외 단기 분석을 통해 선형 예측 계수를 구한다. 이때 고역강조를 통해 직류 성분을 제거하고 성문 등의 저역 필터효과를 제거하였다. 선형 예측 계수는 Levinson-Durbin 알고리즘을 사용해 구했고 이를 다시 켑스트럼 계수로 변환하여 인식을 위한 특징 벡터열로 구축하였다. 각 단어의 특징 벡터 열에 대해 Baum-Welch 추정법을 이용하여 HMM을 훈련시킨 다음, 기능성 계산을 통해 각 단어에 대한 인식을 수행하도록 하였다. 단어 인식을 위해 ARM CPU코어가 장착된 보드에 음성인식 엔진과 데이터 베이스를 포팅하여 실험용 임베디드 시스템을 구축하였다 5가지 인식 계수집단에 대한 인식 실험을 실시하여 인식률이 좋은 계수 집단을 선정하였다. 전체적인 음성인식 엔진의 인식률은 95%이었고 명령어에 대한 인식률은 96%, 숫자음에 대한 인식률은 94%로 나타났다.

• 동의생리병리학회지
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• 제31권2호
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• pp.118-125
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• 2017

The purpose of this study is to investigate the blood pressure reducing effect of Qi-Ju-Di-Huang-Wan (QJDHW) in adults with essential hypertension by using methods of systemic review and meta-analysis. Major search engines, such as PubMed, EMBASE, Cochrane library, Web of Science, CNKI, CiNii, J-STAGE, KISS, NDSL, RISS, OASIS, DBpia and so on, were used. The search period we used is from the start date of the search engine to October 30, 2016 and no language limits were placed. Randomized controlled trials using QJDHW in adults with essential hypertension were searched and extracted by two independent researchers. Meta-analysis was performed on outcome variables of the total effective rate (TER), systolic blood pressure (SBP) and diastolic blood pressure (DBP). Risk of bias (RoB) of Cochrane was used to assess methodological quality. Thirteen studies were finally selected. We observed that the combined treatment of QJDHW and antihypertensive drug had 3.6 times the odds ratio of TER for blood pressure lowering than a single use of an antihypertensive drug. Additionally, mean differences of SBP and DBP were -8.88 mmHg (95% Confidential Interval (CI) -12.77 mmHg, -5.00 mmHg, P<0.00001), -7.09 mmHg (95% CI -9.93, -4.25, P <0.00001), respectively. Single use of QJDHW did not reduce blood pressure more than an antihypertensive drug. All items of RoB were unclear and the methodological quality was low. Our analysis suggests that the combination of QJDHW and antihypertensive drugs may be more effective in reducing blood pressure than a single antihypertensive drug. But due to low methodological quality, careful interpretation will be needed and systematic long-term clinical trials will be required.