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East Linn Christian Academy

East Linn Christian Academy is a private PK through 12th Grade Christian school in Lebanon, United States, serving the families in Lebanon, Sweet Home, Corvallis, Linn County and the Willamette Valley. East Linn Christian Academy was founded by Harold and Dorothy Grove in 1982. "Value People", "Steward with Integrity" and "Transformational Education" is the schools core values used to shape the schools program and teaching styles. The school was at two different locations in Lebanon and Sweet Home. In 2011, the school combined all the grades to one campus in Lebanon Oregon. Since the school has increased the number of classes and buildings as needed for the growth of the school. In 2017, the school started fundraising for additional classrooms, they hope to begin construction by 2019. East Linn Christian Academy has been accredited by the Association of Christian Schools International since 1982, by the AdvancEd since 1996; the school meets the requirements for graduation of the Oregon State Department of Education.

The Academic program schedule follows five day a week, 8 period schedule. Consisting of four days of traditional class periods and one day with shorter periods to accommodate for a chapel service. College credit opportunities exist for high school students to earn college credit at institutions of higher education, including Oregon Institute of Technology. ELC has a growing number of concurrent enrollment courses taught on site, including writing, anatomy and business courses. A strong academic support program aids over 25% of our students, STEM and other advanced courses are offered to challenge the top tier students; the international student program is open to 6th through 12th grade. ELC has the privilege of serving students from the Philippines, Korea, Hong Kong and Japan, their vision is to embrace Acts 1:8, Matthew 28:19 and Mark 16:15 by welcoming students from around the world, helping them to grow in English, becoming more familiar with American tradition and culture. International Students participate in school academic and extra-curricular programs, this provides authentic diversity and global awareness development for the student body which enhances a core value at East Linn Christian Academy.

International students are placed with a qualified host family who can provide additional support to them during their intercultural journey. The school provides both short and long stay opportunities, with many students continuing on to graduate from ELC. East Linn Christian Academy competes in the Oregon School Activities Association as part of the 2A-3 Central Valley Conference. Middle and high school sports offered are baseball, cross country, boys soccer, track & field, volleyball. Elementary students can participate in field; the school hosts a number of community sport camps for all grades from Kinder to 12th grade, which can be found on their online sports page under the sports camp link at. ELC offers a Tuition Assistance Fund to ensure affordable Christian education for our financially diverse community. ELC encourages diversity by designating a portion of the operating budget to be used for financial assistance; the school has a number of fundraisers throughout the year to raise money to help off-set operating cost short-falls, tuition assistance and building development

Pseudospark switch

The pseudospark switch known as a cold-cathode thyratron due to the similarities with regular thyratrons, is a gas-filled tube capable of high speed switching. Advantages of pseudospark switches include the ability to carry reverse currents, low pulse, high lifetime, a high current rise of about 1012 A/sec. In addition, since the cathode is not heated prior to switching, the standby power is one order of magnitude lower than in thyratrons. However, pseudospark switches have undesired plasma phenomena at low peak currents. Issues such as current quenching and impedance fluctuations occur at currents less than 2-3 kA while at high peak currents a transition to a metal vapor arc occurs which leads to erosion of the electrodes. Pseudospark switches are functionally similar to triggered spark gaps. A pseudospark switch's electrodes have central holes 3 to 5 mm in diameter. Behind the cathode and anode lie a hollow cathode and hollow anode, respectively; the electrodes are separated by an insulator.

A low pressure "working gas" is contained between the electrodes. While a pseudospark switch is fairly simple in construction, engineering a switch for higher lifetimes is more difficult. One method of extending the lifetime is to create a multichannel pseudospark switch to distribute the current and as a result, decrease the erosion. Another method is to use cathode materials more resistant to erosion. Typical electrode materials include copper, tungsten/rhenium, molybdenum and ceramic materials. Tantalum, cannot be used with hydrogen due to chemical erosion affecting the lifetime adversely. Of the metals and molybdenum are used, though molybdenum electrodes show issues with reignition behavior. Several papers which compare electrode materials claim tungsten is the most suitable of the metal electrodes tested; some ceramic materials such as silicon carbide and boron carbide have proven to be excellent electrode materials as well, with lower erosion rates than tungsten in certain cases. In a pseudospark discharge a breakdown is first triggered between the electrodes by applying a voltage.

The gas breaks down as a function of the pressure and voltage. An "ionization avalanche" occurs producing a homogeneous discharge plasma confined to the central regions of the electrodes. In the figure above, the various stages of the pseudospark discharge can be seen. Stage is the low current phase; the discharges in both stage, the hollow cathode phase, stage, the borehole phase, are capable of carrying currents of several hundred amps. The transition from the borehole phase to the high current phase is fast, characterized by a sudden jump in switch impedance; the last phase only occurs for currents of several 10 kA and is unwelcome as it results in high erosion rates. Ignitron Krytron IGBT Thyratron Christiansen, J.. "Production of high current particle beams by low pressure spark discharges". Zeitschrift für Physik A. 290: 35–41. Bibcode:1979ZPhyA.290...35C. doi:10.1007/bf01408477. Bochkov V.. "SN-Series Pseudospark Switches Operating Completely Without Permanent Heating. New Prospects of Application".

Acta Physica Polonica A. 115: 980–982. Doi:10.12693/APhysPolA.115.980. Bochkov V.. "Prospective Pulsed Power Applications Of Pseudospark Switches". Proc. 17th IEEE International Pulsed Power Conference. 1: 255–259. Theory and Use of Pseudospark Switches