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91.
沥青作为一种路用结合料,成为公路建设长久使用不衰的一种材料,但由于沥青材质本身的差异,常会使公路出现一些病害。  相似文献   
92.
彭蕙蕙 《价值工程》2010,29(2):219-220
黔桂铁路怀远龙江特大桥(8#~15#)主桥墩基础承台为深水高桩大体积混凝土承台施工,此项施工技术已在深水桥承台施工中多次使用。结合黔桂线的现场施工特点及工期紧迫的要求,固采用钢吊箱围堰进行设计施工,速度快,质量优,效益好。  相似文献   
93.
The paper looks at the impact of migration and workers’ remittances on the competitiveness of the home economy. It extends existing research that concentrated on the exchange rate effects of remittances, the so-called Dutch disease effect, by adding labor market effects. The results show that the labor market effects of emigration and remittances have a significant impact on competitiveness that goes beyond the traditional exchange rate effect.  相似文献   
94.
城市的发展有其特定的内在规律性,其产生、发展、消亡的各个过程都是作为一个有机体变化更新的特定阶段。集聚效应和扩散效应是经济中心城市的两个主要功能。两者不同的机理分别产生"城市病"问题和内城问题。在城市化发展的过程中,集聚效应要先于扩散效应发生,因此内城问题往往产生于城市化后期。在城市的发展进程中,内城问题在表现特征上有着一些与"城市病"问题截然不同的方面,有其特殊的解决对策。  相似文献   
95.
李学峰 《价值工程》2011,30(25):82-82
文章以单跨70m钢筋混凝土系杆拱桥为例,在运用Midas Civil空间有限元分析软件进行建立模型后对结构数据分析控制修正,取数据分析,使其符合结构设计规范,以求为实践提供借鉴。  相似文献   
96.
王前法  张耀永 《价值工程》2009,28(10):88-90
土工格栅的应用很广泛,在水利工程、工民建工程和公路工程均有着大量应用。在路网改建项目,利用土工格栅进行路面病害处理,有效地减少反射裂缝、提高抗车辙能力和增加抗疲劳性能,防止基层产生过大的永久变形和疲劳破坏有着重要的作用。通过在世行贷款恢复类工程项目施工监理实践,对路面病害处理土工格栅施工进行总结。  相似文献   
97.
Abstract

Objective: To describe the incidence of diagnosis of gastroesophageal reflux disease and acid-related conditions (GERD/ARC) throughout childhood and characterize patterns of diagnosis and treatment with proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs).

Methods: Cohorts of GERD/ARC children (age 0–18 years) were identified from a large US administrative claims database covering 1999–2005 using ICD-9 codes. Incidence, healthcare utilization (HCU), costs, therapy discontinuation and switching rates were compared between various age and patient groups.

Results: Between 2000 and 2005 annual incidence of GERD/ARC diagnosis among infants (age ≤1 year) more than tripled (from 3.4 to 12.3%) and increased by 30% to 50% in other age groups. Patients diagnosed by GI specialists (9.2%) were more likely to be treated with PPIs compared to patients diagnosed by primary care physician (PCP). PPI-initiated patients doubled (from 31.5% in 1999 to 62.6% in 2005) and, when compared with H2RA-initiated patients, were associated with 30% less discontinuation and 90% less therapy switching in the first month, and with higher comorbidity burden and pre-treatment total HCU and costs when diagnosed by GI specialists.

Limitations: The use of an exploratory definition for GERD/ARC, administrative claims data and potential coding errors in diagnosis codes used in selection process may limit the generalizability of the results.

Conclusions: GERD/ARC incidence increased for children of all ages between 2000 and 2005. PCPs made the majority of diagnoses. PPI initiations have now surpassed H2RA initiations.  相似文献   
98.
Abstract

Objective:

To compare the healthcare costs of pre-dialysis chronic kidney disease (CKD) patients cared for in a nephrology clinic setting versus other care settings.

Methods:

An analysis of health claims between 01/2002 and 09/2007 from the Ingenix Impact Database was conducted. Inclusion criteria were ≥18 years of age, ≥1 ICD-9 claim for CKD, and ≥1 estimated glomerular filtration rate (eGFR) value of <60?mL/min/1.73?m2. Patients were classified in the nephrology care cohort if they were treated in a nephrology clinic setting at least once during the study period. Univariate and multivariate analyses were conducted to compare average annualized healthcare costs of patients in nephrology care versus other care settings.

Results:

Among the 20,135 patients identified for analysis, 1,547 patients were cared for in a nephrology clinic setting. Nephrology care was associated with lower healthcare costs with an unadjusted cost savings of $3,049 ($11,303 vs. $14,352, p?=?0.0014) and a cost ratio of 0.8:1 relative to other care settings. After adjusting for covariates, nephrology care remained associated with lower costs (adjusted cost savings: $2,742, p?=?0.006).

Limitations:

Key limitations included potential inaccuracies of claims data, the lack of control for patients’ ethnicity in the calculation of eGFR values, and the presence of potential biases due to the observational design of the study.

Conclusions:

The current study demonstrated that pre-dialysis CKD patients treated in nephrology clinics were associated with significantly lower healthcare costs compared with patients treated in other healthcare settings.  相似文献   
99.
杨发青 《价值工程》2011,30(9):136-136
高性能混凝土是近期混凝土技术发展的主要方向,这种采用优质材料配制,便于浇筑、振捣、不离析、力学性能稳定、早期强度高、具有韧性和体积稳定性等性能的耐久的混凝土,特别适用于高层建筑、桥梁以及暴露在严酷环境中的建筑结构。  相似文献   
100.
岳耀辉 《价值工程》2011,30(19):89-89
路基是公路的重要组成部分,是按照路线位置和一定技术要求修筑的带状构造物,承受由路面传来的荷载,应有足够的强度、稳定性和耐久性。本文根据已有的经验,对当前如何保证以最佳的效果解决好公路路基施工技术问题加以研究,使我国的公路建设再上一个新台阶。  相似文献   
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