Thesis (D. Min.)--Trinity Evangelical Divinity School, 2002. / Abstract. Includes bibliographical references (leaves 168-173).

Thesis (D. Min.)--Ashland Theological Seminary, 2008. / Abstract . Description based on microfiche version record. Includes bibliographical references (leaves 132-143).

Precision orbit determination (POD) plays a vital role in the success of space-borne laser altimetry missions, such as ICESat (Ice, Cloud, and Land Elevation Satellite). Although current ICESat POD processing standards are achieving remarkable accuracy, new time-varying geopotential models derived from the GRACE (Gravity Recovery And Climate Experiment) mission were investigated as candidates to improve POD performance for the planned ICESat-2 mission. The objective of this research is to examine the effect of these time-varying geopotential models -- which include models of non-tidal atmospheric and ocean variability, seasonal variability caused by water mass motion, and secular variations caused by present-day ice-melt and glacial isostatic adjustment -- on ICESat POD. The quality of the POD solutions produced with the new geopotential models was quantified by examining the usual orbit quality tests -- DDHL (double-differenced high-low) and SLR (satellite laser ranging) observation residuals and orbit overlaps. Although the solutions produced in every test case indicated consistency and high accuracy of 1-2 cm, these metrics were rather insensitive to the small changes in the POD solutions induced by the new geopotential models, and were incapable of identifying any statistically significant improvements in the POD. However, examination of geographically correlated radial orbit perturbations showed that the radial orbit differences exhibited significant variability on the order of several millimeters, and were coherent with the temporal variability of the models implemented. Since radial orbit errors directly relate to the scientific quantities of interest in the ICESat mission -- the altimetry measurements and derived ice-sheet surface elevations -- this result is of obvious importance. The most notable effects included an annual radial orbit variation of up to 4 mm over the Amazon region induced by implementing the GRACE Annual model, and a secular variation of radial orbit differences over Greenland when the GRACE Trend model was applied. The effect of radial orbit error on ice-sheet altimetry was quantified by examining the mean geographically correlated radial orbit differences. Since the ice sheet elevation rates computed by ICESat scientists are on the order of tens of centimeters per year, it was concluded that, although the radial orbit perturbations are readily observable, with magnitudes on the order of a few millimeters they are too small to have a significant impact on the altimetry science. However, depending on the scientific objectives and radial orbit accuracy requirements set for ICESat-2, these effects may be important, and the use of time-varying geopotential models in ICESat-2 POD may be beneficial. / text

Not available / text

Understanding how global ice volume on the Earth has changed is of significant importance to improving our understanding of the climate system. Fortunately, the geographically unique perturbations in sea level that result from rapid changes in the mass of, otherwise difficult to measure, land-ice reservoirs can be used to infer the sources and magnitude of melt water. We explore the history of land-ice mass changes through the effect that these mass fluxes have had on both global and regional gravity and sea-level fields. / Earth and Planetary Sciences

In the generation of the standard GRACE gravity fields, the K-Band Ranging (KBR) system data is used in its range-rate mode. Because time derivatives attenuate the gravity signal relative to the data noise at the lower frequencies, it is thought that solutions using range data might have better low-degree (low-frequency) characteristics. The purpose of this work is to detail the methods required to generate range-based solutions, to determine some of the properties of these solutions and then to compare them to range-rate based solutions. It is demonstrated that the range-based solutions are feasible. Different subarc lengths and parameterizations were considered. Although, the most effective combination of subarc lengths and parameterizations are not picked, it is concluded that estimating the mixed periodic term along with bias, bias-rate, bias-acceleration and periodic terms degrades the quality of the range based solution and therefore should not be used. Further study is necessary to pick the optimal combination of subarc length and parameterization which would be used in the time-series analysis. / text

This dissertation is a statement concerning Calvin's view of God and Calvin's view of grace, as they appear in the sermons. Contrary to the opinion of Barth and others, to the effect that for Calvin Christ is the mere executor of the Father's inscrutable and symmetrical decrees, we assert that the requirements of the pastoral situation led Calvin to give much more place to election than to reprobation. Predestination for Calvin was essentially election, because the God we know in Jesus Christ is precisely the electing God through whose free grace undeserving sinners are granted faith and perseverance leading to salvation. The nature of God as sovereign mercy, known through Christ, is the focus of Calvin's doctrine of grace. For Calvin the preacher, reprobation's functional status is less one of a fixed decree than of a dark possibility for those who do not respond in faith to the preaching of the Gospel.

No description available.

Thesis (Th. M.)--Calvin Theological Seminary, 2005. / Abstract. Includes bibliographical references (leaves 158-162).

Thesis (M.Phil.)--Hong Kong Baptist University, 1997. / Thesis submitted to the Dept. of Religion and Philosophy. Includes bibliographical references (leaves 99-109).