Implementation and Evaluation of a Tdma Based Protocol for Wireless Sensor Networks

When evaluating MAC layer network protocols for wireless sensor networks performing simulations of a protocol\u27s operation can provide great insight into the performance of the protocol. In order to prove that a protocol will work in a real setting and not just at the theoretical level, however, there is no substitute for evaluation with a physical implementation. This thesis discusses a physical implementation and evaluation of the Many-to-One-Sensor-to-Sink (MOSS) MAC layer protocol for sink based wireless sensor networks using the MAC Layer Architecture for TinyOS. MOSS is a Time Division Multiple Access (TDMA) based protocol first proposed in an earlier work. MOSS aims to utilize the strengths and alleviate the weaknesses of TDMA. In addition to discussing and evaluating the physical MOSS implementation, the process of developing MAC layer protocol implementations with MLA is also discusse

Implementation and Evaluation of a Tdma Based Protocol for Wireless Sensor Networks

When evaluating MAC layer network protocols for wireless sensor networks performing simulations of a protocol\u27s operation can provide great insight into the performance of the protocol. In order to prove that a protocol will work in a real setting and not just at the theoretical level, however, there is no substitute for evaluation with a physical implementation. This thesis discusses a physical implementation and evaluation of the Many-to-One-Sensor-to-Sink (MOSS) MAC layer protocol for sink based wireless sensor networks using the MAC Layer Architecture for TinyOS. MOSS is a Time Division Multiple Access (TDMA) based protocol first proposed in an earlier work. MOSS aims to utilize the strengths and alleviate the weaknesses of TDMA. In addition to discussing and evaluating the physical MOSS implementation, the process of developing MAC layer protocol implementations with MLA is also discusse

Tribute to Judge Duffy | Recollections of Judge Kevin T. Duffy

I first met Judge Kevin Duffy in 1957 when we were both sworn in as Assistant United States Attorneys in the Southern District of New York. Both of us were protégés of Judge J. Edward Lumbard—I had worked in his office during the summer of 1954 when he was U.S. Attorney, and Kevin had just finished clerking for him. He had strongly urged both of us to join the U.S. Attorney’s Office (the “Office”). We both looked up to him enormously. (Later, when Kevin became a district judge, and Judge Lumbard was on the Second Circuit, they had an arrangement where for one month during the year they would exchange law clerks; Judge Lumbard’s would get the experience of being district court clerks, and Kevin’s would get the experience of being circuit court clerks.

Corporations - Preference Rights on Dissolution

The capital structure of the defendant corporation consisted of class A, class B, and preferred stock. According to the articles of association, the class A stock was entitled to a ten percent dividend before any dividend was paid on the class B. After the class B stock had also received a ten percent dividend, the two classes were to share equally in any further dividends. The charter further provided that on dissolution the holders of the class A stock were entitled to cash to the amount of the par value of their stock before any payment in liquidation was made to the holders of the class B stock. Upon dissolution of the defendant, the class A stockholders claimed the right to share equally with the class B stockholders in surplus assets remaining after both had received the par value of their stock. Held, all assets remaining after the holders of class A stock have received par value are to be distributed to the class B shareholders. The preference given class A stockholders on dissolution is clearly exhaustive. Mohawk Carpet Mills, Inc. v. Delaware Rayon Company, (Del. Ch. 1954) 110 A. (2d) 305

Real Property - The Effect of Zoning Ordinances on the Law of Nuisance

One of the most interesting and least explored questions in the law of property is the effect of zoning ordinances on the law of nuisance. Particularly interesting is the extent to which statutory authorization by zoning can legalize a use of land which, in the absence of a zoning ordinance, would constitute a nuisance. In order to understand this problem fully it is necessary to begin with a general analysis of the law of nuisance and the various classifications into which it has been divided by the courts

Insurance - Recovery - Rights of Mortgagee Under Mortgagor\u27s Insurance

Defendant issued a policy of fire insurance on an automobile plaintiff had purchased with money borrowed from one Hansen, to whom a note and a chattel mortgage were given as security for the debt. A week after the policy was issued naming plaintiff as the insured, defendant executed an amendment to the policy in the form of an endorsement reading, Less if any ... shall be paid to the insured and Charles H. Hansen as their interests may appear. The policy provided that it should not apply while the car was subject to any mortgage or other encumbrance not specifically declared and described in the policy. The premium was paid by Hansen. After the automobile was destroyed by fire, plaintiff sued on the policy and the defendant demurred, alleging failure to state a cause of action. The demurrer was overruled and judgment entered for plaintiff and Hansen. Defendant then amended its petition to allege that plaintiff had executed three additional chattel mortgages on the car that violated the provision against encumbrances. Held, admitting the policy might be void as to plaintiff, this does not affect defendant\u27s liability to Hansen. Koenke v. Iowa Mut. Cas. Co., 175 Kan. 473, 264 P. (2d) 472 (1953)

Evidence - Attorney-Client Privilege - Communications Relating to Future Criminal Transactions

Defendant was subpoenaed in connection with a grand jury investigation of gambling and corruption of public officials. He had been retained by one \u27Willie Moretti as attorney for five of his associates in October, 1950 after a complaint charging a gambling conspiracy had been filed against them. During some two hundred conferences with Moretti in the following year, defendant learned that protection money was being paid to certain high ranking state officials, Moretti at one point complaining of the frequent demands of these officials for more· money. Moretti also discussed with defendant a visit he had paid to the home of one Dickerson, a prominent political figure, twelve days after the aforementioned complaint had been filed. With respect to this visit, Dickerson testified that Moretti had complained that people who had paid protection money were being pushed around, and that he (Moretti) had paid protection money. Dickerson interpreted these remarks as an attempt to pressure him into interceding with the grand jury on Moretti\u27s behalf. Moretti himself was a witness before the Kefauver Committee in 1951, and was indicted after his death in 1951 for conspiracy to obstruct justice. Upon being asked to disclose the names of the people, who, according to Moretti, had received protection money, and to state whether Moretti had told him that he had been to Dickerson\u27s home and had a conversation, defendant claimed the attorney-client privilege and refused to answer. Upon an order to show cause why defendant should not answer the above questions, the trial court sustained the claim of privilege and the appellate division affirmed. On appeal, held, reversed, three judges dissenting. The two hundred unexplained conferences within a year, the visit to Dickerson, and Moretti\u27s complaint about the greed of public officials constitute prima facie evidence that Moretti consulted defendant with regard to future criminal transactions, to which the privilege does not attach. In re Selser, (N.J. 1954) 105 A. (2d) 395

Admiralty- Conflict of Laws - Application of the Jones Act

Admiralty traditionally did not give a seaman a right of action for negligence unless it could be attributed to the unseaworthiness of the vessel. An injured seaman was limited to two remedies: an action for maintenance and cure, or an action based on -unseaworthiness. To remedy this situation, Congress in 1920 passed the Jones Act. This act was framed in terms of any seaman who shall suffer personal injury in the course of his employment, and gave to such seamen all the rights granted by statutes modifying or extending the common law right or remedy in cases of personal injury to railway employees. Although this act accomplished its purpose of giving injured seamen an action for negligence, it did not specify who was included within the term any seaman, but left this to judicial interpretation. Through the years, there has been a gradual movement away from the pre-Jones Act conception that maritime torts should be governed by the law of the Hag, and an extension of the statute on the basis of other factors. A recent decision by the United States Supreme Court has given some indication as to which of these factors should bear the most weight in the choice of law applicable to a maritime I tort and has indicated a retreat from the more recent extensions

Numerical studies of constraints and gravitational wave extraction in general relativity

Within classical physics, general relativity is the theory of gravity. Its equations are non-linear partial differential equations for which relatively few closed form solutions are known. Because of the growing observational need for solutions representing gravitational waves from astrophysically plausible sources, a subfield of general relativity, numerical relativity, has a emerged with the goal of generating numerical solutions to the Einstein equations. This dissertation focuses on two fundamental problems in modern numerical relativity: (1) Creating a theoretical treatment of the constraints in the presence of constraint-violating numerical errors, and (2) Designing and implementing an algorithm to compute the spherical harmonic decomposition of radiation quantities for comparison with observation. On the issue of the constraints, I present a novel and generic procedure for incorporating the constraints into the equations of motion of the theory in a way designed to make the constraint hypersurface an attractor of the evolution. In principle, the prescription generates non-linear corrections for the Einstein equations. The dissertation presents numerical evidence that the correction terms do work in the case of two formulations of the Maxwell equations and two formulations of the linearized Einstein equations. On the issue of radiation extraction, I provide the first in-depth analysis of a novel algorithm, due originally to Misner, for computing spherical harmonic components on a cubic grid. I compute explicitly how the truncation error in the algorithm depends on its various parameters, and I also provide a detailed analysis showing how to implement the method on grids in which explicit symmetries are enforced via boundary conditions. Finally, I verify these error estimates and symmetry arguments with a numerical study using a solution of the linearized Einstein equations known as a Teukolsky wave. The algorithm performs well and the estimates prove true both in simulations run on a uniform grid and in simulations that make use of fixed mesh refinement techniques