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31.
Chaos theory, informational needs, and natural disasters 总被引:2,自引:0,他引:2
Timothy L. Sellnow Matthew W. Seeger Robert R. Ulmer 《Journal of Applied Communication Research》2002,30(4):269-292
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning. 相似文献
32.
Richard A. Epstein 《Journal of Cultural Economics》2003,27(3-4):259-274
Ordinary markets allow parties, not the state, to value property and projects. But they do not account for subjective value in such traditional contexts as condemnation. An awareness of these nonmarket values helps overcome any categorical opposition to the use of the contingent valuation method (CVM) to value cultural and environmental resources. But accurate CVM should measure all values, positive or negative, tononowners; it should apply generally to any substitute projects; and it should seek to account for diminishing marginal value of additional resource units. CVM should be used only to aggregate nonmarket preferences, not to skew the political debate to cultural or environmental objectives. 相似文献
33.
The purpose of this study was to determine test-retest reliability for the 1-mile, 3/4-mile, and 1/2-mile distance run/alk tests for children in Grades K-4. Fifty-one intact physical education classes were randomly assigned to one of the three distance run conditions. A total of 1,229 (621 boys, 608 girls) completed the test-retests in the fall (October), with 1,050 of these students (543 boys, 507 girls) repeating the tests in the spring (May). Results indicated that the 1-mile run/walk distance, as recommended for young children in most national test batteries, has acceptable intraclass reliability (.83 less than R less than .90) for both boys and girls in Grades 3 and 4, has minimal (fall) to acceptable (spring) reliability for Grade 2 students (.70 less than R less than .83), but is not reliable for children in Grades K and 1 (.34 less than R less than .56). The 1/2 mile was the only distance meeting minimal reliability standards for boys and girls in Grades K and 1 (.73 less than R less than .82). Results also indicated that reliability estimates remained fairly stable across gender and age groups from the fall to spring testing periods, with the exception of the noticeably improved values for Grade 2 students on the 1-mile run/walk test. Criterion-referenced reliability (P, percent agreement) was also estimated relative to Physical Best and Fitnessgram run/walk standards. Reliability coefficients for all age group standards were acceptable to high (.70 less than P less than .95), except for Fitnessgram standards for 5-year-old girls on the 1-mile test for both fall and spring and for 6-year-old boys and girls on the 1-mile test administered in the spring. 相似文献
34.
35.
D A Sedlock 《Research quarterly for exercise and sport》1991,62(2):213-216
This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p greater than .05). Mean (+/- SD) values were 9.2 +/- 3.3 and 10.4 +/- 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p greater than .05) between the upper body (22.9 +/- 13.7 min) and lower body (24.2 +/- 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise. 相似文献
36.
Audrey L. Qualls 《Educational Measurement》2001,20(1):9-16
What is the typical amount of student answer‐changing that takes place in a low‐stakes test environment? Can we use this information to look for evidence of improper answer‐changing (cheating) on high‐stakes test? 相似文献
37.
The many challenges faced by health sciences libraries of all types and sizes often require innovative solutions. When an innovative solution involves calculated risk taking, the approach is called intrapreneurial. At the University of Miami School of Medicine, an intrapreneurial approach solved the fiscal problems of the biomedical communications unit. The Louis Calder Memorial Library inherited these problems when the Department of the Library and Biomedical Communications was created in the early 1980s. In this paper, two intrapreneurial programs are described, and the benefit and suitability of this management style to information services are demonstrated. 相似文献
38.
L. DiANNE BORDERS 《Counselor Education & Supervision》1991,31(1):32-47
A multiple case study of four supervisors indicated that numerous factors shape supervisors' in-session performance and revealed a complex interplay between thoughts and behaviors. 相似文献
39.
Thomas L. Bonn 《Publishing Research Quarterly》1993,9(1):3-19
New World Writing, a magazine founded by New American Library in 1952, quickly became an important vehicle for liberal intellectual
and literary thought. In addition to providing an outlet for new writing, the magazine became an important acquisitions tool
for NAL. Throughout its lifetime, New World Writing remained a showcase for many of the finest writers of the 1950s, including
Christopher Isherwood, Louis Auchincloss, Tennessee Williams, Flannery O’Connor, Jack Kerouac, and Gore Vidal.
He is the author of Under Cover: An Illustrated History of American Mass Market Paperbacksand Heavy Traffic and High Culture: The New American Library as Literary Gatekeeper. He is working on a study of American literary
agents 相似文献
40.
Renáta Tichá Christine A. Espin Miya Miura Wayman 《Learning disabilities research & practice》2009,24(3):132-142
The validity and reliability of curriculum‐based measures in reading as indicators of performance and progress for secondary‐school students were examined. Thirty‐five grade 8 students completed reading aloud and maze‐selection measures weekly for 10 weeks. Criterion measures were the state standards test in reading and the Woodcock–Johnson III Test of Achievement. Different time frames for each measure were compared. Most alternate‐form reliability coefficients were above .80. Criterion‐related validity coefficients ranged from .77 to .89. No differences related to time were found. Only maze selection reflected significant growth, with an average increase of 1.29 correct choices per week. Maze growth was related to the reading performance level and to change on the Woodcock–Johnson III from pre‐ to posttest. 相似文献