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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1982. / Supervised by Sean C. Solomon. Vita. Includes bibliographical references (leaves 312-321).

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982. / Includes bibliographical references.

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982. / Includes bibliographical references (p. 312-321).

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1983. / Includes bibliographical references.

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1984. / Vita. Bibliography: p. 200-206.

Uppsatsen bygger på en undersökning om hur tre företag arbetar med CSR. Syftet med undersökningen har varit att granska hur de utvalda företagen väljer att kommunicera dess CSR-arbete till externa intressenter.De frågeställningar studien bygger på är: Hur väljer företag att kommunicera CSR? Kommunicerar företag inom olika branscher CSR på samma sätt? Ser företag inom olika branscher samhällsansvaret på likvärdigt sätt? Finns det någon koppling mellan företags externa kommunikation av CSR och företags medierelation? Under arbetets gång har en respondent från respektive företag intervjuats. En innehållsanalys har även genomförts av företagens hemsidor. Undersökningen har gett författaren kunskap om att de undersökta företagen anser att CSR-arbetet bör finnas utspritt inom hela verksamheten och inte enbart skötas av en person. För att lyckas nå ut till sina externa intressenter på ett effektivt och trovärdigt sätt måste det sociala ansvaret vara en självklarhet för alla inom organisationen och vara en del av företagets vision. Synen på samhällsansvaret skiljde sig mellan företagen vilket kan bero på att det är en tolkningsfråga vad företagen anser är ett socialt samhällsansvar. Dock satte samtliga företag som deltagit i undersökningen in miljöfrågor och sociala frågor i begreppet. De olika företagen som befinner sig i olika branscher arbetar med liknande frågor fast deras tillvägagångssätt och huvudfråga kan skilja sig något mellan branscherna. Hur företagen än väljer att definiera begreppet och hur de än väljer att arbeta med dessa frågor är det en stor fördel att även kommunicera vad de gör till media. Media kan nämligen vara en effektiv kanal för företaget att nå ut till sina intressenter samt att skapa trovärdighet

The fishing method of trawling, or dragging, has long been shown to be harmful to a plethora of sea life inhabiting the world?s oceans and inland waterways. Fishing nets scour the seabed, disturbing everything in their path, while usually in search of only one type of bottom-dwelling species. Impacts to the seafloor include a removal of topographic features, disturbance of the upper sediment layers, including deep furrows, as well as physical and chemical changes to sediment morphology. While biological organisms and communities can potentially recover from this destruction, archaeological data cannot. Fishermen have been raising important artifacts in their nets for over a century. These finds have helped archaeologists locate significant sites, but they also have the adverse effect of irreparably damaging these sites. This thesis explores the impacts of bottom trawling on underwater cultural heritage. The methods and gear used by trawlers and their documented effects upon the sea floor are identified. Examples of the types of damage shipwreck sites receive after being impacted by trawling are presented. Instances where fishermen have raised prehistoric artifacts from inundated land sites are also introduced. The fishing and archaeological communities must cooperate to limit further damage to underwater cultural heritage around the globe.

This study discusses the three-dimensional refraction of progressive wave trains propagating over a bottom of circular concentric contours and the results are expressed in a polar coordinate. First, a general differential formulation of refraction is derived via three different methods: by transferring from its original Cartesian form to the polar coordinate, by applying the Fermat¡¦s principle in polar coordinate, and by applying the conservation of waves in polar coordinate. All three approaches give the same governing equation; hence, its correctness is verified. Based on this governing equation, the wave ray, the phase function, the constant phase line, and the refraction coefficient are all determined. In the present refraction problem for an originally uniform wave train propagating over a bottom of circular concentric contours, a few special features, including the cusps of constant phase lines due to the effect of bottom, and the envelope composed of these cusps, are present. All these refraction properties can be expressed in terms of both a snapshot and a time evolution of constant phase lines. In the lee side of the shoal, there exists a sheltered zone that is enclosed by the envelope of the cusps. In this zone, wave rays intersect and the corresponding caustic problem arises, and all possible combinations of intersecting rays are also specifically described in this study. The difficulty of classical ray theory for the caustic problem is overcome and the caustic phenomenon and its refraction coefficients are determined explicitly in this study.

Recovery of unattached offshore facilities or missing equipments is a challenging activity. Generally speaking, this activity involves a comprehensive procedure which includes: target characterization, searching, detection, verification, locating, reacquisition and salvage. Among them, target searching and detection are the most critical components of the whole procedure. The purpose of this investigation was dedicated in discussing the efficiency by the application of side-scan sonar, magnetometer and sub-bottom profiler simultaneously in searching, detecting, identifying and locating underwater stationary targets. Procedures of this research include: 1. Discussing the capabilities of instruments and verification cruises on target. 2. Discussing the salvage activity we conducted off Kaohsiung harbor on a depleted anchor. 3. Estimating the practicability of the methodology. According to the characteristics of these apparatus, the water depth, collected by echo sounder, is capable of expressing the relief of the seabed. Seabed sonographs, recorded by side-scan sonar, show that it is feasible to detect, verify and locate targets on the seabed. Sub-bottom profiler provides the sub-surface sedimentary information which can be used to detect buried targets. Magnetometer can detect environmental magnetic intensities, which can locate and determine the size of ferrous targets. Two depleted anchors were recorded off Kaohsiung harbor on the navigation chart. A recovery plan was then arranged which included 4 phases: collection of anchor characteristics, initial field survey and target detection, target verification and locating, target recovery. The underwater searching equipment employed in this activity include: side-scan sonar, sub-bottom profiler, magnetometer, echo sounder, underwater positioning system (include GPS), remotely operated vehicle (ROV) and professional divers. The offshore working platform used in this activity was R/V Ocean Research#3. Results of the initial search phase by side-scan sonar indicated there was only one potential target in the searching area. Follow up verification cruises confirmed acoustically that the target was an anchor with a piece of chain clogged on a block. The results of this investigation included the information such as the dimensions and the location of the anchor. Furthermore, the reason which caused the anchor being abandoned on the seafloor was derived. For underwater ferrous targets, such as anchor and chain cable, all of the aforementioned apparatus, have good potential for their detection and verification. It can be concluded that, applying these apparatus simultaneously can more effectively conduct searching, detecting, identifying and locating underwater stationary targets than by the application of a single instrument such as side-scan sonar system. Optical verifications of this target by ROV were attempted, nevertheless, were not success due to the difficulties in maneuvering OR#3 into proper position. An attempt to recovery this target by divers was arranged. But due to bad weather and rough sea state, the divers were not even allowed to dive. However, according to the experiences collected, a target reacquisition and recovery facility was built to fulfill the necessity of guiding divers to the target and lift it.