Curriculum vitae

Name:Dr. Vyas Darshan G.

Designation:I/C Head(Coordinator) & Lecturer,

Physics Department,

Hem. N. G. University, Patan.

D.O.B.:17-04-1977

Nationality:INDIAN

Sex:Male

Father’s Name:Prof. Ghanshyambhai P. Vyas

(Retired professor, L.D.Engg.College,A’bad)

Category:OPEN

Languages Known:English, Hindi, Gujarati

Hobbies:Classical Music, Cricket, Chess

Address for Correspondence:

5,Hina park society, Part-1,

Umiyavijay, Satellite Road,

Ahmedabad-380015.

E-mail:

Phone no.:(079)26608719

Mobile no.:9426374957

Educational Qualification:

Degree / Institution & University / Subject Studied / Year of Passing / Total marks with Percentage
N.E.T. / University Grant Commission
New Delhi / Electronics / December-1999
Ph.D. / Physics/Electronics Department
Saurashtra University,Rajkot / Microprocessor
& Peripherals / March-2006
M.Sc.
SEM-4 / Physics Department
School of science,
Gujarat University,A’bad / Electronics / 1999 / 527 / 650
82%
M.Sc.
SEM-3 / Physics Department
School of science,
Gujarat University,A’bad / Electronics / 1998 / 533 / 650
82%
M.Sc.
SEM-2 / Physics Department
School of science,
Gujarat University,A’bad / Electronics / 1998 / 521 / 650
81%
M.Sc.
SEM-1 / Physics Department
School of science,
Gujarat University,A’bad / Electronics / 1997 / 529 / 650
82%
T.Y.B.Sc. / Gujarat Arts & Science college,
Gujarat University,A’bad / Electronics / 1997 / 625 / 850
74%
S.Y.B.Sc. / Gujarat Arts & Science college,
Gujarat University,A’bad / Electronics
Physics / 1996 / 719 / 1000
72%
F.Y.B.Sc. / Gujarat Arts & Science college,
Gujarat University,A’bad / Physics
Chemistry
Maths / 1997 / 615 / 1000
62%
H.S.C. / Gujarat Higher Secondary Education Board, Gandhinagar / Science / 1993 / 380 / 800
48%
S.S.C. / Gujarat Secondary Education Board,Gandhinagar / Science / 1991 / 456 / 800
57%

Title of Ph.D. :

DESIGN AND FABRICATION OF GENERAL PURPOSE 8085 CARD AND DEVELOP VARIOUS INTERFACING CARDS USEFUL IN EDUCATION OF ELECTRONICS.

Design of the new curricula and courses

Year 2009-10

  1. New M.Sc. (Electronics) curriculum (Four semester Pattern) is design and started in department which is effective from June-2009.

Year 2010-11

  1. M.Sc. (Electronics) Syllabus is revised as per CBCS semester pattern which is effective from June-2010.

Professional Qualifications:

 Passed U.G.C.-N.E.T. examination in December-1999.

 Computer language certificate course in ACT.

Projects done:

 Designed and constructed Microcontroller based “Temperature Indicator and Controller” using I.C. 89C52.

 Designed and constructed “Running Character Display” using 8085 based microprocessor kit.

 Designed and constructed P.C.B. hardware and software to understand mode-2 of PPI 8255.

 Constructed DPM using I.C. 7107

 Constructed two bands Radio Receiver.

 Designed and constructed fixed 10KHz Sinusoidal wave generator using Wein bridge.

 Designed and constructed Regulated D.C. Power Supply using I.C. LM 317.

 Designed and constructed Astable Multivibrator.

Computer Skills:

 Serial communication using RS-232, Parallel and USB.

 Programming in C, C++, Java, Embedded-C.

 MS-Office, MS-DOS, Windows etc.

 Schematic design and P.C.B. layout preparation using computer.

Information about Prizes & Scholarships

 Gujarat University first with 82% in M.Sc.(Electronics) in 1999.

 Gujarat Arts & Science college (Gujarat University) first in T.Y.B.Sc and won Dr.Y.J.Nayak award of Rs.151/- cash in 1997.

 Gujarat University was awarded me a merit scholarship in M.Sc for two years.

 Merit scholarship from “Avdichya Kharedi Samvay Mandal”.

 IETE journal of education Paid Rs.1000/- for paper publication it their journal.

 EFY paid Rs.5500/- for article publication in their magazine.

Teaching Experience at P.G. level:

 Department of Physics,

Hemchandracharya North Gujarat University, Patan.

Lectures, Laboratory and design and development of new experiments.

M.Sc.(Physics & Electronics) Practicals

Lectures: Microprocessor, Programming in C, Basic Electronics, Digital Electronics.

New laboratory developed for M.Sc.(Physics)-Part I and II and M.Sc.(Electronics) SEM.-1

 Department of Physics,

School of science, Gujarat University, Ahmedabad.

Lectures, Laboratory and design and development of new experiments.

M.Sc.(Physics & Electronics) Practicals

Lectures:Microprocessor and Microcontroller

New Experiments developed:

  1. Traffic light control
  2. Interfacing of 8085 kit with I.C. 8155
  3. Interfacing of 8085 kit with I.C. 8255
  4. Interfacing of 8085 kit with I.C. 8253
  5. Programming of microcontroller 8051 on P.C. software
  6. Programming of 8085 to interface stepper motor

 Department of Electronics,

Saurashtra University,Rajkot.

Lectures, Laboratory and design and development of new experiments.

Microprocessor and Communication

New Experiments developed:

  1. P.C.B. Schematic and layout (Auto Route) Preparation
  2. P.C.B. Schematic and layout (manual) Preparation
  3. P.C.B. Development by using Negative of circuit layout
  4. Study of 8255 using microprocessor kit
  5. Study of 24-channel logic analyzer
  6. Amplitude Modulation and demodulation using mixer and detector circuit.

Teaching Experience at Undergraduate level:

 Physics Department,

Bhavan’s R.A. College of Science, Ahmedabad.

Lectures and Laboratory

S.Y.B.Sc.

Laplace Transformation, Low frequency and high frequency amplifier circuits, Network analysis, Electrical Active and Passive components etc.

T.Y.B.Sc.

Transducers, OP-AMP, Power Supply, Microprocessor, etc.

F.Y.B.Sc.(Physics) Practicals

S.Y.B.Sc.(Physics & Electronics) Practicals

T.Y.B.Sc.(Electronics) Practicals

 Physics Department,

Gujarat Arts & Science College, Ahmedabad.

Lectures and Laboratory

F.Y.B.Sc.Radioactivity, Quantum mechanics etc.

T.Y.B.Sc.Fiber Optics, Radio wave Propagation, Antenna etc.

F.Y.B.Sc.(Physics) Practicals

S.Y.B.Sc.(Physics & Electronics) Practicals

T.Y.B.Sc.(Electronics) Practicals

Teaching Experience in Private classes:

 Dhumraketu Infotech

Faculty of Microprocessor, Microcontroller, C, C++ and JAVA

Special Achievements

 UGC-NET qualified from Gujarat University.

 University first rank in M.Sc.

 College first rank in T.Y.B.Sc.

 Demonstrated new experiments in refresher courses at Physics Department, Gujarat University, Ahmedabad.

 P.G. teaching experience of three universities, Gujarat University, Saurashtra University and Hem. N. G. University.

 Worked as an expert in M.Sc.(Physics and Electronics) at Gujarat University and Saurashtra University.

 Worked as an Examiner in B.Sc.(Physics) and B.Sc.(Electronics) College examinations.

 Worked as a Paper setter, Examiner, Laboratory Supervisor and Expert in M.Sc. (Physics) University Examination at Hem. North Gujarat University, Patan.

 Co-opt as a Science faculty member from Physics in Hem. North Gujarat University, Patan.

 Invited as a resourced person to deliver the lecture on Physics at Science college, Pilvai.

 Committee member of Hem. North Gujarat University Physics Teachers’ Association.

 Worked as Physics expert in the interview committee of the Adhyapak Sahayak in sir P.T. Science collage, Modasa by Hem. N.G.University latter no. AK/559/C-607/2006 dated 27/11/2006.

 Worked as Physics expert in the interview committee of the Adhyapak Sahayak in The HNSB Ltd. Science College, Himannagar by Hem. N.G.University latter no. AK/559-1/C-615/2007 dated 03/01/2007.

 Appointed as a member in the Local Inquiry Committee at Hemchandracharya North Gujarat University, Patan No./PG/Kendra/494/2007 dated 16/01/2007.

 Worked as Physics expert in the interview committee of Adhyapak Sahayak in the Science college, Palanpur dated 27/11/2007

 Worked as Physics expert in the interview of Lecturer at L.C.Institute of Technology, Bhandu, Mehesana on 21/08/2008.

 Worked as an expert in committee for SRF (Under Rajiv Gandhi National Fellowship) at Department of Electronics, Saurashtra University, Rajkot dated 26th December, 2008.

 Member of the centralized P.G.admission committee of the science faculty of Hemchandracharya North Gujarat University, Patan in the year 2009-10

 Worked as external Physics expert in the interview committee of the Physics teacher for higher secondary school run by Sarvoday Kelavni Mandal, At. & Po. Kanodar, Ta. Palanpur Dist. Banaskantha dated 9th August, 2009

 Worked as a judge in “District Science Seminar-2009” at Punabha CSC, recognized and funded by GUJCOST dated 18th August, 2009.

 Worked as a judge in science/maths exhibition at Nirman High school,C.G.Road, Ahmedabad organized by Department of District Education and Training, Ahmedabad dated 30th September, 2009

 Member of the centralized P.G.admission committee of the science faculty of Hemchandracharya North Gujarat University, Patan in the year 2010-11 Ref No. PG/Admission/3036/2010 dated 31/05/2010.

 Appointed As chairman for M.Sc.(Electronics) in H.N.G.University, Patan for year 2009-10(Semester-1).

 Appointed as convener in Adhoc Board of Study (M.Sc. Electronics) Ref.No. Ace./AS/3903/2010 dated 21/06/2010.

 Appointed As chairman for M.Sc.(Electronics) in H.N.G.University, Patan for year 2010(Semester-I and II).

 Appointed as paper setter/examiner for Ph.D. entrance examination for year-2010.

 Appointed as M.Phil(Physics) Coordinator dated 11th August, 2011 University office order no. 26/2011 Ref No. PG/M.Phil/5233/2011.

Educational Tour with students:

  1. One day seminar on Physics Education and Research organized by Pramukh swami science & H.D. Patel arts college, Kadi and sponsored by UGC dated 9th October,2010
  2. One day Science stage show by Prof.M.G.Tarneket organized by IAPT and GUJCOST at Science College, Palanpur dated 27th July, 2006.
  3. One day competition and district level seminar on international year of physics-2005 at P.S.Science college, Kadi jointly organized by IAPT and GUJCOST dated 3rd January, 2006.

Publications in reputed journals/Magazines/Conferences

Year 2011-12

  1. (Sole Author) Microcontroller based Electronic Calculator, Electronics For You, Vol.-43, No.-6, August 2011 Page No. 115 to 118.(ISSN 0013-516X)

Year 2010-11

  1. (Sole author) Design and construction of simple ADC experiment using PIC 16F72, Journal of Laboratory Experiments, Vol.-11, No.-4, March-2011 Page No. 15 to 20. (ISSN 0972-6055)
  2. (Sole author) Developing experiments for deeper understanding of PIC 16F72 in timing insensitive mode, Journal of SCI-TECH Research,Vol.-2, Issue-1(Paper accepted ISSN 0974 – 9780)

Year 2009-10

  1. (Sole author) Development of software to change the radix of a real number, LE , Journal of Laboratory Experiments, Vol.-9, No.-4, Dec.-2009 Page No. 280 to 284.(ISSN 0972-6055)
  2. The experiment to find the CBW for IR light communication, Bulletin of the Indian Association of Physics Teachers (IAPT), Volume-1, No.-09, September-2009 Page No. 234 to 238.[Authors: D.G.VYAS & K.R.PATEL]

Year 2008-09

  1. (Sole Author) An Unconventional queer multiplexing technique for SSDs, Jouranl of Education, IETE, Vol.- 49, No.-3, sept.-Dec-2008, Page No. 115 to 120.(ISSN 0970-1664)
  2. (Sole Author) Experimental Understanding about I/O, Counters/Timers and Interrupts of AT89C52, Electronics Maker, Issue-145, No.-13, June-2008, Page No. 41 to 45.

Year 2007-08

  1. Study of Intensity Modulation in IR communication, LE, Lab Experiments, Volume-8, No.-1, March-2008 (ISSN 0972-6055), Page No. 25 to 35.[Authors: D.G.VYAS & K.R.PATEL]
  2. (Sole Author) Stop Clock using Microcontroller AT89C52, LE , Lab Experiments, Volume- 7, No.-3, September-2007 (ISSN 0972-6055), Page No. 211 to 219

Year 2006-07

  1. (Sole Author) Computer Keyboard function study using 89C52 Microcontroller and Logic State Analyzer, LE, Lab Experiments, Volume-7, No-1, March-2007 (ISSN 0972-6055), Page No. 39 to 57
  2. (Sole Author) The Clock with Alarm using AT89C52 PART-2, Electronics Maker, Issue-130, No.-12, March-2007, Page No. 37 to 41.
  3. A New Experiment to Establish An Optical Communication Using infrared Light, Bulletin of the Indian Association of Physics Teachers (IAPT), Volume-24, Number-3, March-2007, Page No. 78 to 81.[Authors: D.G.VYAS & K.R.PATEL]
  4. (Sole Author) The Clock with Alarm using AT89C52 PART-I, Electronics Maker, Issue-129, No.-12, February-2007, Page No. 40 to 43.
  5. (Sole Author) Build Yourself Educational software for the KBC-2 PART-II, Electronics Maker, Issue 127, No.-11, December-2006, Page No. 42 to 45.
  6. (Sole Author) Build Yourself Educational software for the KBC-2 PART-I, Electronics Maker, Issue 126, No.-11, November-2006, Page No. 48 to 51.
  7. (Sole Author) Low cost Electrical Power Alarm for the Farmers, Bulletin of the Indian Association of Physics Teachers (IAPT), Volume-23, Number-8, August-2006, Page No. 272 to 273 and contd. On page No.278.
  8. (Sole Author) Software for objective test using C. LE, Lab Experiments, Volume-6, No-2, June-2006. (ISSN 0972-6055), Page No. 131 to 139.

Year 2005-06

  1. Interfacing module for 8085 based systems for solving Boolean equations. Electronics Maker, Vol.-02, No.11, February 2006, Page No. 41 to 45.[Authors: H.N.PANDYA & D.G.VYAS]
  2. Priority Interrupt Controller 8259. LE, Lab Experiments, Vol.-5, No.-4, Dec.-2005. (ISSN 0972-6055), Page No. 328 to 333. [Authors: H.N.PANDYA & D.G.VYAS]

Year 2004-05

  1. Study of interfacing module to establish communications between a PC and a 8085 based microprocessor kit. LE, Lab Experiments, Volume-4,No-3,September-2004. (ISSN 0972-6055), Page No. 219 to 226[Authors: D.G.VYAS, B.H.VYAS & H.N.PANDYA]
  2. Study of 8255 through experiments using microprocessor kit, LE, Lab Experiments, Volume-4,No-2,June-2004(ISSN 0972-6055), Page No. 89 to 100. [Authors: H.N.PANDYA, M.C.NANAVATI & D.G.VYAS]
  3. 8085 based novel software technique for V to F type analog to digital conversion. Electronic Maker, June-2004, Page No. 57 to 62. [Authors: H.N.PANDYA & D.G.VYAS]

Electronics Project Kits designed:

  1. The Clock with date, time and alarm using microcontroller AT89C52.(2008-09)
  2. The low cost electrical power alarm for the farmers.(2006-07)
  3. The stop clock to store five events using microcontroller AT89C52.(2007-08)
  4. The embedded Calculator using microcontroller AT89C52.(2009-10)
  5. The +5 Volt Regulated Power Supply using 7805.(2005-06)
  6. The + 15 volt Regulated power supply for OP-AMP using 7815 and 7915(2005-06)
  7. The Regulated Variable power supply using LM317.(2005-06)

Software designed:

  1. The game show KBC-2 using C-language(2006-07)
  2. The objective test using C-language(2006-07)
  3. Admission and reshuffling software for M.Sc.(Chemistry) of H.N.G.University using V.B.(2009-10)
  4. Software to calculate basic and arrear of 6th UGC pay commission using V.B. (2009-10)

Orientation Course:

  1. Orientation program completed with Grade A at Academic staff College, Saurashtra University, Rajkot from 07/03/2011 to 03/04/2011.

List of Seminars/Workshops attended:

Year 2011-12

  1. Two day international cross disciplinary seminar on ”Creating Excellence for sustainable society” at Hemchandracharya North Gujarat University, Patan dated 15th and 16th May, 2011.

Year 2010-11

  1. Two day workshop on Disater Risk Reduction in Higher Education at Academic Staff College, Saurashtra University, Rajkot dated 9th and 10th March, 2011.
  2. Two day International conference on themes of Higher Education : Prospects of Gujarat organized by Knowledge consortium of Gujarat (KCG) and Department of Education at Pandit Deendayal Petroleum University, Gandhinagar dated 25th and 26th November, 2010.
  3. One day workshop on CBCS and Internal evaluation organized by H.N.G.University dated 20th November, 2010.
  4. One day workshop on research initiatives organized by H.N.G.University and H.N.G.U. Teachers Association (HeNGUTA) dated 21st, October, 2010.
  5. One day user awareness programme under N-list programme organized by H.N.G.University dated 19th October,2010.
  6. One day capacity building workshop organized by H.N.G.University and Knowledge Consortium of Gujarat (KCG) on 15th October, 2010.
  7. One day seminar on Physics Education and Research organized by Pramukh swami science & H.D. Patel arts college, Kadi and sponsored by UGC dated 9th October,2010.

Year 2009-2010

  1. One day xxiv-GSC-2010at Gujarat University organized by Gujarat University and Gujarat Science Academy on 21st March,2010.
  2. One day seminar on Current Trends in Physics at Physics Department, Gujarat University, Ahmedabad organized by Gujarat University, Indian national Science Academy and PRL on 14th March, 2010.

Year 2008-09

  1. Two days national workshop on Light Scattering: Its Applications in Astrophysics and Other Fields organized by Gujarat Arts and Science College at Ahmedabad on 7th and 8th November, 2008.

Year 2007-08

  1. One day workshop on Intellectual Property Rights organized by Government Engineering College, Patan at T.K.Rangbhavan, Hem. North Gujarat University, Patan on 21st February, 2008.

Year 2006-07

  1. One day IAPT regional seminar on Physics Education and Research at Physics Department, Sardar Patel University, Vallabh Vidhyanagar on 8th April,2007.
  2. One day seminar on Science and the knowledge society organized by Gujarat Science Congress and Hemchandracharya North Gujarat University at Patan on 11th March,2007.
  3. One day seminar on Microwave and its applications organized by Department of Physics, Gujarat University, Ahmedabad at Ahmedabad Management Association (AMA) Hall, ATIRA Campus, Ahmedabad on 21st January,2007.
  4. One day seminar on Upgrading Physics Education & Research organized by IAPT and GUJCOST at Physics Department, Science College, Palanpur on 19th, November, 2006.

Year 2005-06

  1. One day seminar of Gujarat Science Congress organized by Gujarat University at Ahmedabad on 26th March, 2006.
  2. One day competition and district level seminar on international year of physics-2005 at P.S.Science college, Kadi jointly organized by IAPT and GUJCOST dated 3rd January, 2006.

Year 2004-05

  1. One day seminar of Gujarat Science Congress at Physics Department, Hem.N.G.University, Patan.
  2. One day Seminar on “SUPERCOMPUTING” and CSI-students branch opening at Computer Department, Hem. N.G.University, Patan dated 8th January, 2005.

Year 2003-04

  1. One day seminar on Emerging trends in advanced communication technology at A.V.Parekh Technical Institute,Rajkot dated 17th May,2004.
  2. One day Participation in 18th Gujarat Science Congress at Physics Department, Saurashtra University, Rajkot dated 13th March,2004.
  3. Two days National Seminar ETA-2004 at Computer Department, Saurashtra University, Rajkot dated 25th ,26th Feb.-2004.
  4. Three days National Seminar ETA-2003 at Computer Department, Saurashtra University, Rajkot dated 11th ,12th and 13th July,2003.

Training Programmes

Year 2009-10

  1. One week Short Term Training Programme on Computational and Simulation aspects of Nano Science and Enginnering at Government Engineering College, Patan Sponcered by GUJCOST, DST and Government of Gujarat dated 18th to 22nd January, 2010(One Week).

Year 2003-04

  1. One day participation in free training program for CADENCE P.C.B. Designing software at Surya Hotel, New Delhi. (Department Of Electronics, Saurashtra University, Rajkot purchased this software)

List of Paper Presented in semenars

Year 2011-12

1.Study of fiberless simplex visual light communication, Two days national symposium on advances in materials science and technology organized by Gujarat University and sponcered by DST,UGC etc. on 3rd & 4th February, 2012.

Year 2010-11

  1. Developing experiments for deeper understanding of PIC 16F72 in Timing insensitive mode, One day seminar on Physics Education and Research organized by P.S.Science and H.D.Arts College, Kadi and sponsored by UGC on 9th October, 2010.

Year 2006-07

  1. A new Experiment to establish an optical communication using infrared light, One day seminar on Upgrading Physics Education & Research organized by IAPT, GUJCOST(CSC, Palanpur) and Physics Department, Science College, Palanpur on 19th, November, 2006

Year 2003-04

  1. Understanding interrupts of 8085 using Logic Analyzer.ETA-2004,25th & 26th FEB.-2004, Computer Department, Saurashtra University, Rajkot, Abstract on Page No. 73. [Authors: H.N.PANDYA & D.G.VYAS]
  2. Design and construction of analog to digital conversion interfacing module for 8085 microprocessor kit. 18th Gujarat Science congress, Physics Department, Saurashtra University, Rajkot dated 13th March,2004. [Authors: D.G.VYAS, M.C.NANAVATI, B.H.VYAS & H.N.PANDYA]
  3. An intelligent control panel : A novel microprocessor based system. ETA-2003, 11th , 12th ,13th July,2003, Computer Department, Saurashtra University, Rajkot, Abstract on Page No. 73. [Authors: H.N.PANDYA & D.G.VYAS]

ORGANISED SEMINAR/POPULAR LECTURE/EXHEBITION

Year 2010-11

  1. Arranged the Regional seminar (District Science Seminar-2010) and Chair the session as a judge at Punabha Community Science Center, Patan Funded by GUJCOST dated 13th August, 2010.

Year 2009-10

  1. Arranged the Regional Seminar and Chair the session as a judge for oral presentations, poster presentation and popular lecture at Physics department, HNGU, Patan based on “Awareness & information on ozone and prevention of ozone layer” dated 16th Sept.,2009 funded by Punabha CSC(GUJCOST), and HNGU, Patan

Year 2008-09

  1. Arranged the popular lectures and demonstration of experiments based on “Expanding Horizons of Science” at Punabha CSC(GUJCOST), Aadarsh school, Patan dated 28th Feb.,2009

Year 2006-07

  1. Working as local committee member in XXI-GSC , jointly organized by Gujarat Science Academy & HNGU dated 11th March,2007.
  2. Arranged the Regional Seminar and chair the session as a judge for oral presentations, poster presentation and popular lecture at physics department, HNGU,Patan based on “OZONE DAY” dated 16th Sept.,2006 funded by Punabha CSC (GUJCOST) and HNGU, Patan
  3. Arranged local semenar on Teacher’s day at Physics Department, Hem.North Gujarat University, Patan dated 5th September, 2006.
  4. The Physics Experiment exhibition arranged at “ Punabha community science center(GUJCOST), Aadarsh school, Patan ( N.G.)”, funded by GUJCOST, G’nagar on 04/08/2006.

Year 2005-06

  1. Arranged the popular lectures of Dr.J.N.Desai (LASER and some of their unusual applications) and Dr.R.M.Pandya (Remote sensing and its applications) at Physics Department, HNGU, Patan dated 4th Feb.,2006

Chair the session in Seminar

  1. Arranged the Regional seminar (District Science Seminar-2010) and Chair the session as a judge at Punabha Community Science Center, Patan Funded by GUJCOST dated 13th August, 2010.
  2. Arranged the Regional Seminar and Chair the session as a judge for oral presentations, poster presentation and popular lecture at Physics department, HNGU, Patan based on “Awareness & information on ozone and prevention of ozone layer” dated 16th Sept.,2009 funded by Punabha CSC(GUJCOST), and HNGU, Patan
  3. Arranged the Regional Seminar and chair the session as a judge for oral presentations, poster presentation and popular lecture at physics department, HNGU,Patan based on “OZONE DAY” dated 16th Sept.,2006 funded by Punabha CSC (GUJCOST) and HNGU, Patan

1