全文获取类型
收费全文 | 131篇 |
免费 | 3篇 |
专业分类
134篇 |
出版年
2023年 | 1篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 8篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 34篇 |
2012年 | 6篇 |
2011年 | 1篇 |
2008年 | 3篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 3篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1966年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有134条查询结果,搜索用时 15 毫秒
81.
Sara Hughes 《政策研究杂志》2012,40(4):650-673
Solving conflictual environmental policy problems is increasingly falling under the purview of local governments and public agencies. Nonregulatory approaches, such as the development of voluntary environmental programs (VEPs), could offer a useful policy alternative as they often have greater political traction and flexibility. However, there has been little work examining the use of VEPs in the public sector. This article uses a new dataset from California to examine how political institutions affect decisions by local governments and public agencies to participate in a voluntary urban water conservation program and whether this program has improved the water conservation performance of its members. The results show that special district governments, private utilities, and water suppliers dependent on purchased water are more likely to participate in the program and to join early. However, urban water agencies that have joined the program have not reduced their per capita water use more than those that have not. These results underscore the influence of political institutions in public‐sector decision making and demonstrate that, as in the private sector, commitment to a VEP by local government and public agencies does not guarantee implementation or environmental improvements. While voluntary programs offer political and administrative advantages, in order for VEPs in the public sector to be effective they must be accompanied and supported by credible enforcement mechanisms, performance standards, and rigorous monitoring programs. 相似文献
82.
Sarah U. Wisseman Randall E. Hughes Thomas E. Emerson Kenneth B. Farnsworth 《Journal of archaeological science》2012
Midcontinental pipestone quarries in Missouri, Minnesota, Wisconsin, Illinois, Ohio, and Kansas were utilized by a number of native cultures from 5000 YRBP through historic times. Except for Gunderson’s pioneering work on catlinite, the mineralogy of these sources was poorly understood until recently. For fifteen years, a University of Illinois team of archaeologists and geologists has used well-established mineralogical methods (X-ray diffraction [XRD] and reflectance near-infrared spectroscopy [NIS]) to identify and characterize nine pipestone quarries and match sources with archaeological artifacts from major Hopewell and Mississippian culture sites. NIS analyses of raw materials from nine major pipestone quarries show distinct mineralogical differences between sources but relatively uniform composition within each source. The major distinguishing minerals estimated from NIS spectra match very well with earlier results from XRD and inductively-coupled plasma (ICP) analyses. Results demonstrate that NIS is a reliable non-destructive technique for discriminating between midcontinental pipestones and for sourcing pipestone artifacts. 相似文献
83.
84.
85.
86.
87.
88.
89.
Marjorie Sullivan Philip Hughes Amy Mosig Way Nigel Spooner 《Archaeology in Oceania》2014,49(1):43-55
A site in the Olympic Dam area, recorded during archaeological surveying as a silcrete quarry, was investigated. Hand‐excavated squares and subsequent machine‐excavated trenches revealed an ancient “mine” rather than a simple surface quarry. Blocks of high‐quality silcrete were levered from below the ground surface and many were knapped in the immediate area. Rubble in the pit backfills included large numbers of flakes. Single‐grain optical dates from sediments in the backfilled pits demonstrate that the silcrete “mining” occurred during a short period in the late Holocene. 相似文献
90.