Abstract:
Methods, systems, and apparatuses for measuring an electric potential in the earth, which includes a first sensor are disclosed. The first sensor includes a sensing plate for placement in an environment in close proximity to the earth. The sensing plate has an operative capacitive coupling with the earth and measures the earth's electric potential. The sensor also includes a barrier providing electrochemical segregation between the sensing plate and the earth and an amplifier having at least one stage for receiving and amplifying a first signal carrying the potential measured by the sensing plate. The sensor also includes a first connection carrying the first signal from the sensing plate to the amplifier; and a reference voltage for application to the first stage of the amplifier, the reference voltage providing a reference against which the potential measured by the sensing plate is compared. Other embodiments are described and claimed.
Abstract:
The sequencing of individual monomers (e.g., a single nucleotide) of a polymer (e.g., DNA, RNA) is improved by reducing the motion of the polymer due to thermally-driven diffusion to reduce the spatial error in the position of the polymer within a measurement device. A major system parameter, such as average translocation velocity or measurement time, is selected based on the characteristics of the sensing system utilized, and an algorithm jointly optimizes the sequencing order error rate and the monomer identification error rate of the system.
Abstract:
An integrated array of electronic sensing elements outputs a bio-fingerprint of an analyte. System is preferably constructed of as a series of three layers but need not be so arranged. An upper layer defines a fluid volume or analyte chamber; a middle layer contains the sensing elements; and a third layer contains electronic readout elements. The analyte chamber contains an electrolyte and the analyte to be detected. The sensing elements are optimized for maximum detection sensitivity in the minimum response time. The response of each sensing element is read out by a dedicated sensing electrode. Around each electrode is a control ring. The potential of the control ring is set to attract analytes of interest to the sensing elements.
Abstract:
An underwater EM measurement system, which is substantially smaller, much simpler to use, and more robust than prior systems, is formed as a sensor package integrated into a single pressure vessel includes two magnetic sensors including induction coils disposed substantially horizontally so as to measure fields in orthogonal directions. The package also includes two electric field sensors including electric potential antennas adapted to couple to a water potential via a capacitive electrode having a conducting material and an electrically insulative layer formed of an insulating material. The capacitive electrode has a capacitance to the medium of greater than 1 mF. Preferably, the insulating material is a metal oxide.
Abstract:
An underwater EM measurement system, which is substantially smaller, much simpler to use, and more robust than prior systems, is formed as a sensor package integrated into a single pressure vessel includes two magnetic sensors including induction coils disposed substantially horizontally so as to measure fields in orthogonal directions. The package also includes two electric field sensors including electric potential antennas adapted to couple to a water potential via a capacitive electrode having a conducting material and an electrically insulative layer formed of an insulating material. The capacitive electrode has a capacitance to the medium of greater than 1 mF. Preferably, the insulating material is a metal oxide.
Abstract:
Methods, systems, and apparatuses for measuring an electric potential in the earth, which includes a first sensor are disclosed. The first sensor includes a sensing plate for placement in an environment in close proximity to the earth. The sensing plate has an operative capacitive coupling with the earth and measures the earth's electric potential. The sensor also includes a barrier providing electrochemical segregation between the sensing plate and the earth and an amplifier having at least one stage for receiving and amplifying a first signal carrying the potential measured by the sensing plate. The sensor also includes a first connection carrying the first signal from the sensing plate to the amplifier; and a reference voltage for application to the first stage of the amplifier, the reference voltage providing a reference against which the potential measured by the sensing plate is compared. Other embodiments are described and claimed.
Abstract:
A self-locating mounting apparatus for holding objects such as sensors at specific positions on a subject's head includes a central mount constituted by a plurality of inextensible elements adapted to fit over the top of a subject's head. In addition, the mounting apparatus includes an adjustable circumferential band adapted to circle the subject's head and connect the central mount to inextensible side elements via sliding joints. A plurality of biasing elements provide a force for biasing sensor mounting units on the mounting apparatus against a subject's head, allowing for long-term sensing while minimizing interference forces on the mounting units. Advantageously, the mounting apparatus holds sensors within approximately 5 mm of their desired measurement positions over a range of subject head sizes.
Abstract:
A non-invasive measurement system (110) for measuring the electrical potential of a voltage source (20, 120) includes a sensing electrode (50, 151) spaced from the voltage source (20, 120). Preferably the voltage source (20, 120) is within a biological cell (115) located in a nutrient bath (119) including electrolytic medium (117) and an object (30, 190) is a portion of the electrolytic fluid (117) located between the cell (115) and the sensing electrode (50, 151). A feedback electrode (181) is formed in an annular shape and surrounds the sensing electrode (50, 151) thus creating an annular fluid region therebetween. The value of the voltage in the annular region (131) is set substantially equal to the value of the voltage in the object (190) and therefore the impedance between the object (190) and a stray voltage source (40) is maximized.
Abstract:
The sequencing of individual monomers (e.g., a single nucleotide) of a polymer (e.g., DNA, RNA) is improved by reducing the motion of the polymer due to thermally-driven diffusion to reduce the spatial error in the position of the polymer within a measurement device. A major system parameter, such as average translocation velocity or measurement time, is selected based on the characteristics of the sensing system utilized, and an algorithm jointly optimizes the sequencing order error rate and the monomer identification error rate of the system.
Abstract:
A self-locating mounting apparatus for holding objects such as sensors at specific positions on a subject's head includes a central mount constituted by a plurality of inextensible elements adapted to fit over the top of a subject's head. In addition, the mounting apparatus includes an adjustable circumferential band adapted to circle the subject's head and connect the central mount to inextensible side elements via sliding joints. A plurality of biasing elements provide a force for biasing sensor mounting units on the mounting apparatus against a subject's head, allowing for long-term sensing while minimizing interference forces on the mounting units. Advantageously, the mounting apparatus holds sensors within approximately 5 mm of their desired measurement positions over a range of subject head sizes.