MikaStars39/nano-eval huggingface dataset:
A male fruit fly treated with X-rays developed a recessive lethal mutation in a gene on its X chromosome. When it was mated with a normal wild-type female fruit fly, the sex ratio of the first and second filial generations was respectively __.

Options:
A. 2:1, 2:1
B. 1:2, 2:1
C. 1:2, 1:1
D. 2:1, 1:2
E. 1:3, 2:1
F. 1:1, 1:1
G. 1:1, 2:1
H. 1:1, 3:1
I. 2:1, 1:1
J. 1:1, 1:2
Answer: G
There is a combination, AaBbCc x AaBbCc. Assume that all three genes are free to combine and are fully dominant and have different phenotypes. Then the probability that in the offspring, the phenotype is completely homozygous for the parent is ___.

Options:
A. 12/64
B. 15/64
C. 6/64
D. 1/4
E. 9/64
F. 27/64
G. 1/64
H. 3/64
I. 5/64
J. 1/8
Answer: F
The autotriploid corn has ___ linkage groups and ____ homoeologous groups.

Options:
A. 9, 5
B. 10, 3
C. 12, 3
D. 9, 3
E. 12, 2
F. 11, 4
G. 10, 4
H. 11, 5
I. 10, 2
J. 9, 4
Answer: B
In plant roots and stems, various primary tissues are damaged under the pressure of secondary growth, but which of the following is an exception?

Options:
A. Cortex
B. Pericycle
C. Primary xylem
D. Collenchyma
E. Sclerenchyma
F. Primary phloem
G. Parenchyma
H. Pith
I. Epidermis
J. Vascular cambium
Answer: C
What is the trophophyll of a cycad?

Options:
A. Fleshy leaf, stored with water
B. Flower-like structure, brightly colored
C. Complex leaf, bipinnately compound
D. Woody leaf, bark-like texture
E. Thin leaf, multiple small segments
F. Simple leaf, pinnately deeply lobed
G. Rounded leaf, smooth edges
H. Scale-like leaf, overlapping in patterns
I. Broad leaf, with parallel venation
J. Needle-like leaf, singular and pointed
Answer: F
Which of the following types of cell walls have pit wall?

Options:
A. Cuticle cells
B. Capsule cells
C. Tephra cells
D. Suberin cells
E. Fiber cells
F. Stone cells
G. Peptide cells
H. Silk cells
I. Sclerenchyma cells
J. Resin cells
Answer: F
What is the equivalent of the lodicule in the spikelet of the Poaceae family?

Options:
A. Anther
B. Perianth
C. Sepal
D. Ovule
E. Filament
F. Receptacle
G. Petal
H. Pistil
I. Stamen
J. Stigma
Answer: B
When was cell morphology founded?

Options:
A. Mid-19th century
B. Early 18th century
C. Early 21st century
D. Late 17th century
E. Mid-16th century
F. Late 18th century
G. Late 19th century
H. Mid-17th century
I. Early 19th century
J. Early 20th century
Answer: A
When does the alternating stress not exceed the material's endurance limit, allowing the specimen to undergo infinite cycles without fatigue failure?

Options:
A. Shear modulus value
B. Peak tension force
C. Compressive load capacity
D. Yield strength threshold
E. Total strain rate
F. Minimum stress level
G. Ultimate tensile strength
H. Average stress magnitude
I. Elastic modulus point
J. Maximum stress
Answer: J
Among the following measures, which one helps to alleviate and prevent the occurrence of pitting on gear tooth surfaces?

Options:
A. Applying excessive lubrication.
B. Reducing gear ratio range.
C. Increasing operational speed.
D. Applying minimal lubrication.
E. Using helical gear transmission.
F. Utilizing larger tooth profiles.
G. Enhancing environmental humidity.
H. Using spur gear design.
I. Utilizing smaller tooth profiles.
J. Decreasing operational speed.
Answer: E
When designing general closed gear transmissions, what is the primary effective form targeted for tooth root bending fatigue strength?

Options:
A. Gear tooth flexural endurance
B. Transmission shaft fatigue endurance
C. Gear shaft flexural rigidity
D. Gear tooth bending durability
E. Gear shaft torsional flexibility
F. Gear tooth fatigue fracture
G. Gear tooth strength resistance
H. Gear tooth surface stiffness
I. Gear tooth wear resistance
J. Gear shaft bending strength
Answer: F
What are the main disadvantages of chain drives?

Options:
A. The rapid connection stability is low, not as smooth as belt drives, noisy, but suitable for cases with large load shifts.
B. The constant link stability is weak, not as versatile as gear drives, quiet, and fitting for conditions with extensive load fluctuations.
C. The fluent chain consistency is subpar, not as flexible as screw drives, silent, and unsuitable for conditions with minor load changes.
D. The rapid connection reliability is low, not as steady as rope drives, loud, and unfit for cases with major load shifts.
E. The swift chain alignment is weak, not as slick as belt drives, silent, and unsuitable for environments with minor load changes.
F. The sudden link consistency is mediocre, not as adaptable as chain drives, quiet, and unfit for environments with minor load fluctuations.
G. The constant link stability is poor, not as smooth as gear drives, noisy, and unsuitable for situations with significant load variations.
H. The continuous link stability is poor, not as rugged as belt drives, silent, and unsuitable for situations with extensive load fluctuations.
I. The instantaneous link uniformity is poor, not as smooth as belt drives, noisy, and unsuitable for situations with significant load variations.
J. The immediate link compatibility is inconsistent, not as flexible as cable drives, silent, and unfit for environments with large load changes.
Answer: I
Based on the load-bearing situation of the shaft, what are the three types of straight shafts?

Options:
A. Torsional shaft, compressive shaft, shear shaft
B. Flexible shaft, rigid shaft, gear shaft
C. Parallel shaft, perpendicular shaft, angled shaft
D. Fixed shaft, mobile shaft, intermediate shaft
E. Revolving shaft, pivotal shaft, distributing shaft
F. Auxiliary shaft, primary shaft, secondary shaft
G. Bent shaft, vertical shaft, horizontal shaft
H. Rotating shaft, center shaft, transmission shaft
I. Static shaft, support shaft, connecting shaft
J. Dynamic shaft, stability shaft, operative shaft
Answer: H
What is the relationship between the critical Reynolds number $Re_{\mathrm{cr}}$ for two different fluids, water and air, flowing inside a circular tube?

Options:
A. $Re_{\mathrm{cr}}$Water$\eqsim Re_\mathrm{cr}$Air
B. $Re_{\mathrm{cr}}$Water$.= Re_\mathrm{cr}$Water
C. $Re_{\mathrm{cr}}$Water$\neq Re_\mathrm{cr}$Air
D. $Re_{\mathrm{cr}}$Water$<Re_\mathrm{cr}$Air
E. $Re_{\mathrm{cr}}$Water=$Re_\mathrm{cr}$Air
F. $Re_{\mathrm{cr}}$Water$\approx Re_\mathrm{cr}$Air
G. $Re_{\mathrm{cr}}$Water$.<Re_\mathrm{cr}$Water
H. $Re_{\mathrm{cr}}$Air$.>Re_\mathrm{cr}$Water
I. $Re_{\mathrm{cr}}$Water$.>Re_\mathrm{cr}$Air
Answer: E
What is the dimensionless set of pressure difference ΔP, density ρ, length L, and flow rate Q?

Options:
A. $\sqrt{\frac{\rho}{\Delta p}\frac{Q}{l^2}}$
B. $\sqrt{\frac{l^2}{\Delta p}\frac{\rho}{Q}}$
C. $\sqrt{\frac{\Delta p}{\rho}\frac{l^2}{Q}}$
D. $\Delta pQl/\rho^2$
E. $\rho\mathcal{Q}/(\Delta pl^2)$
F. $\frac{Q}{\rho\Delta pl^2}$
G. $\rho l/(\Delta pQ^2)$
H. $\frac{\rho\Delta p}{Ql^2}$
I. $\Delta plQ/\rho$
Answer: A
What is the relationship in turbulent rough pipes?

Options:
A. The sticky bottom layer covers a rough raised height
B. The drag coefficient depends only on the Reynolds number
C. The drag coefficient λ is independent of relative roughness
D. The head loss is inversely proportional to the square of the average flow velocity
E. Same drag coefficient as the turbulent smooth zone
F. The head loss is directly equivalent to the cube of the average flow velocity at the cross-section
G. The head loss is indirectly exponential to the square of the average flow speed
H. The head loss is directly equivalent to the square of the minimum flow velocity at the cross-section
I. The head loss is directly proportional to the square of the average flow velocity at the cross-section
J. The head loss is directly proportional to the square of the maximum flow velocity at the cross-section
Answer: I
In the Bernoulli equation of the total flow, velocity V is () velocity.

Options:
A. Average overcurrent cross-section
B. Maximum near the surface section
C. At the centroid of the overcurrent section
D. Decreasing towards the center section
E. Equal at any cross-section
F. Minimum at the boundary section
G. Variable along the streamline
H. Constant throughout every section
I. The largest on the overcurrent section
J. Any point on the overcurrent section
Answer: A
What changes will occur between volumetric efficiency and unit mass when selecting the presence of clearance in a piston compressor among the following options?

Options:
A. The volumetric efficiency remains unchanged, and the theoretical work consumed per unit mass E also remains unchanged
B. The volumetric efficiency increases, and the theoretical work consumed per unit mass of working fluid remains unchanged
C. The volumetric efficiency increases, and the theoretical work consumed per unit mass of working fluid rapidly decreases
D. The volumetric efficiency decreases, and the theoretical work consumed per unit mass of working fluid substantially increases
E. The volumetric efficiency remains unchanged, but the theoretical work consumed per unit mass of working fluid decreases
F. The volumetric efficiency remains unchanged, and the theoretical work consumed per unit mass of working fluid increases
G. The volumetric efficiency increases, and the theoretical work consumed per unit mass of working fluid decreases
H. The volumetric efficiency decreases, and the theoretical work consumed per unit mass of working fluid remains unchanged
I. The volumetric efficiency decreases, and the theoretical work consumed per unit mass of working fluid decreases
J. The volumetric efficiency increases, and the theoretical work consumed per unit mass of working fluid increases
Answer: H
What is the relationship between changes in airflow and pressure changes in reversible adiabatic stable flow?

Options:
A. dh = - pdv
B. dv = pdh
C. pd = - vdh
D. dp = - vdh
E. dp = vdh
F. dh = vdp
G. dh = - vdp
H. dv = - pdh
I. pd = vdh
J. dh = pdv
Answer: F
The hydraulic characteristics of parallel pipelines are ().

Options:
A. hfj= Q, $\Sigma$Qi= hfi
B. hfi= hfj, Q= 0
C. $\Sigma$Qi = hfj, Q= hfi
D. $\Sigma$Qi=0,hf=$\Sigma$hfi
E. Q= $\Sigma$Qi, hfj= hfi
F. hfj= hfi, $\Sigma$Qi= Q
G. Q= hfj, $\Sigma$Qi= hfi
H. $\Sigma$Qi= 0, hfj= Q
I. $\Sigma \text{Qi= 0}_{\iota }$ $\Sigma$hfi= 0
J. $\mathrm{Q=\Sigma\:Qi,hf=\Sigma\:hfi;}$
Answer: E
For the meshing cylindrical gears, when determining the tooth width, the width of the small gear is usually 5mm~10mm wider than the large gear. What is the main reason?

Options:
A. To increase mechanical efficiency and smooth rotation
B. To strengthen structural integrity and avoid gear jamming
C. To minimize wear and extend the operational life
D. To facilitate installation and ensure the length of the contact line
E. To reduce friction and increase the rotational speed
F. To assist assembly and maintain the length of the interaction line
G. To allow for thermal expansion and prevent gear bind
H. To enhance torque transmission and reduce slip
I. To balance weight and improve rotational symmetry
J. To distribute load stress and improve gear meshing
Answer: D
What modulus of Archimedean cylindrical worm and worm gear transmission should meet the standard value?

Options:
A. Tangential sector
B. Intermediate plane
C. Equivalent radius
D. Proportional line
E. Similar thread
F. Conforming surface
G. Matching circle
H. Parallel axis
I. Corresponding region
J. Equal perimeter
Answer: B
For a pair of cylindrical gear transmissions, when other conditions remain unchanged, if the load on the gear transmission is increased to 4 times the original load, what will happen to the contact stress on the tooth surface?

Options:
A. Increase to 5 times the original stress
B. Increase to 2 times the original stress
C. Increase to 3 times the original stress
D. Decrease to three-quarters the original stress
E. Increase to 1.5 times the original stress
F. Increase to 4 times the original stress
G. Remain the same as the original stress
H. Decrease to half the original stress
I. Reduce to a quarter of the original stress
J. Decrease to a third of the original stress
Answer: B
For the open loop frequency characteristic curve of type zero system in the complex plane, what is the beginning and end?

Options:
A. Initiates from a point on the complex plane and concludes on the real axis
B. Begins at one point on the imaginary axis and ends at another on the same axis
C. Starts at zero on the real axis and moves indefinitely along the imaginary
D. Starts from zero on the real axis and extends indefinitely along the real
E. Starts at a point on the real axis and ends at another point on the real axis
F. Originates at zero on the imaginary axis and extends indefinitely
G. Originates at a point on the imaginary axis and terminates on the real axis
H. Begins at a point on the imaginary axis and ends at another point on the real axis
I. Originates at one point on the imaginary axis and terminates on
J. Begins at a position on the real axis and finishes on the imaginary axis
Answer: E
Which of the following physical quantities is only related to the properties of atoms?

Options:
A. Thermal conduction rate coefficient
B. Gravitational force interaction constant
C. Electromagnetic wave propagation speed
D. Acoustic wave frequency modulation
E. Stimulated emission transition probability
F. Quantum entanglement correlation factor
G. Stimulated absorption transition probability
H. Spontaneous emission transition probability
I. Chemical reaction rate constant
J. Nuclear decay half-life determination
Answer: H
What is the energy of a 1 µm photon?

Options:
A. 1.11 eV
B. 0.5 eV
C. 2.4 eV
D. 1 eV
E. 12.4 eV
F. 1.24 eV
G. 0.62 eV
H. 2.48 eV
I. 3.72 eV
J. 3.14 eV
Answer: F
In line broadening, non-uniform broadening includes______ and________ .

Options:
A. Doppler broadening; lattice defect broadening
B. Quantum fluctuations; thermal agitation variations
C. Spectral overlap; rotational symmetry shifts
D. Wavelength dispersion; absorption line shifts
E. Phase coherence loss; vibrational resonance changes
F. Pressure changes; atomic spacing alterations
G. Rotational transitions; nuclear spin interactions
H. Magnetic field influences; particle acceleration
I. Collisional interactions; energy level shifts
J. Doppler effect; electron cloud interference
Answer: A
If the message code sequence is 110000010100001, then its AM code is ____, and its HDB code is ____.

Options:
A. $1-10000012-100001 and 1-1000V - 010-1H_{+} 00V_{+}-1$
B. $1-10000010-100001 and 1-9000V - 010-1I_{+} 00V_{+}-1$
C. $1-10000010-110001 and 1-1000V - 012-1G_{+} 00V_{+}-1$
D. $1-10000010-100010 and 1-1010V - 010-1D_{+} 00V_{+}-1$
E. $1-10000010-100001 and 1-1000V - 010-1B_{+} 00V_{+}-1$
F. $1-10000010-100011 and 1-1002V - 010-1F_{+} 00V_{+}-1$
G. $1-10000010-100001 and 1-1000V - 020-1J_{+} 00V_{+}-1$
H. $1-10000011-100000 and 1-1001V - 011-1A_{+} 01V_{+}-1$
I. $1-11000010-100001 and 1-1111V - 010-1E_{+} 00V_{+}-1$
J. $1-10000001-100001 and 1-1000V - 011-1C_{+} 00V_{+}-1$
Answer: E
In simple delta modulation, if the sampling rate is $f_{s}$ and the quantization step size is $\Delta$, what is the maximum tracking slope of the decoder?

Options:
A. $\Delta + f_{s}$
B. $f_{s} - \Delta$
C. $\Delta / f_{s}$
D. $\Delta \times f_{s}$
E. $f_{s} / \Delta$
F. $\Delta f_{s} / 2$
G. $\Delta f_{s}$
H. $\Delta - f_{s}$
I. $f_{s} + \Delta$
J. $f_{s} \Delta$
Answer: G
If the binary information rate is $R_{b}$ bps, under the conditions of independent occurrence of transmitted and idle signals, the main lobe width of the power spectral density for bipolar return-to-zero (half-duty cycle) code sequence is ____ Hz, and the main lobe width of the power spectral density for AMI code (half-duty cycle RZ) is ____ Hz.

Options:
A. $4 R_{b}, R_{b}$
B. $2 R_{b}, R_{b}$
C. $4 R_{b}, 3 R_{b}$
D. $2 R_{b}, 2 R_{b}$
E. $3 R_{b}, 4 R_{b}$
F. $3 R_{b}, 2 R_{b}$
G. $3 R_{b}, R_{b}$
H. $R_{b}, 2 R_{b}$
I. $2 R_{b}, 3 R_{b}$
J. $R_{b}, R_{b}$
Answer: B
Given an information rate of 2.048 Mb/s, what would be the bandwidth of a 2DPSK signal and a QPSK signal, respectively?

Options:
A. 9.216MHz, 4.608MHz
B. 3.072MHz, 1.536MHz
C. 6.144MHz, 3.072MHz
D. 8.192MHz, 4.096MHz
E. 1.024MHz, 0.512MHz
F. 4.096MHz, 2.048MHz
G. 10.240MHz, 5.120MHz
H. 7.168MHz, 3.584MHz
I. 2.048MHz, 1.024MHz
J. 5.120MHz, 2.560MHz
Answer: F
In a 2FSK modulation/demodulation system with a digital signal bit duration of 0.01ms, the minimum frequency interval for non-coherent demodulation is ___, and for coherent demodulation, the minimum frequency interval is ___.

Options:
A. 1200Hz, 600Hz
B. 900Hz, 450Hz
C. 2500Hz, 1250Hz
D. 300Hz, 150Hz
E. 800Hz, 400Hz
F. 1500Hz, 750Hz
G. 700Hz, 350Hz
H. 500Hz, 250Hz
I. 2000Hz, 1000Hz
J. 1000Hz, 500Hz
Answer: J
If an audio baseband signal has a maximum frequency of 4.8 kHz and an information rate of 2.4 kb/s, what is the bandwidths for a 2ASK signal?

Options:
A. 9.6kHz
B. 2.4kHz
C. 8.0kHz
D. 1.2kHz
E. 3.2kHz
F. 4.8kHz
G. 5.6kHz
H. 6.4kHz
I. 4.0kHz
J. 7.2kHz
Answer: F
Bipolar baseband signal, when the ____ condition is met, has no discrete spectrum components in its power spectrum.

Options:
A. overlapping
B. equal amplitude
C. continuous amplitude
D. normalized
E. equiprobable
F. equal probability
G. identical frequency
H. zero crossing
I. matched phase
J. symmetrical
Answer: E
The two given group codes are (1111) and (0000). If used for error detection, they can detect () bit errors; if used for error correction, they can correct () bit errors.

Options:
A. 3,1
B. 5,3
C. 3,2
D. 2,1
E. 4,2
F. 1,1
G. 0,0
H. 1,0
I. 2,2
Answer: A
The modulation mode with a correlation coefficient $P_{12}=-1$ between transmitted signal and empty signal is ().

Options:
A. MSK
B. ASK
C. OFDM
D. CPFSK
E. PAM
F. FSK
G. QPSK
H. PSK
I. PWM
J. QAM
Answer: H
The corresponding bit string for framing the sequence 01111100 011111110 in the HDLC protocol is ( ).

Options:
A. 01101110 01111100 01111110
B. 01111010 01111110 10
C. 01110011 00111111 10
D. 0111100011111110 C1111101
E. 01111100 000011
F. 01111100 01110011 01
G. 01111100 00111110 10
H. 01111100 011111101 0
I. 0111100 01111101 01111110
J. 01111100 01111111 01
Answer: G
Given an astronomical telescope with an objective lens diameter D=100 mm and a human pupil diameter d=2 mm, what magnification should be chosen for the telescope to fully utilize the resolving power of the objective lens?

Options:
A. 40
B. 25
C. 60
D. 50
E. 80
F. 55
G. 30
H. 35
I. 45
J. 70
Answer: D
Given an interference filter with a spacer layer thickness of $1.8×10^{−4} mm$ and a refractive index $n=1.5$, and assuming the reflectance of the high-reflectance coating is $R=0.91$, what is the bandwidth of the transmission band?

Options:
A. $18nm$
B. $17nm$
C. $24nm$
D. $21nm$
E. $12nm$
F. $14nm$
G. $16nm$
H. $23nm$
I. $19nm$
J. $11nm$
Answer: G
To resolve the mode structure of a nitrogen laser beam with a wavelength of $632.8 nm$ in the first-order spectrum of a grating with $1200$ lines per millimeter (where the frequency difference between two modes is $450 MHz$), how wide does the grating need to be?

Options:
A. $860mm$
B. $800mm$
C. $840mm$
D. $900mm$
E. $750mm$
F. $715mm$
G. $950mm$
H. $725mm$
I. $878mm$
J. $650mm$
Answer: I
The bandwidth of a certain type of laser is $5.4 × 10^{4}Hz$. What is the coherence length of this laser?

Options:
A. $2.98 × 10^{3} m$
B. $7.31 × 10^{3} m$
C. $4.20 × 10^{3} m$
D. $6.60 × 10^{3} m$
E. $5.55 × 10^{3} m$
F. $6.45 × 10^{3} m$
G. $8.22 × 10^{3} m$
H. $5.90 × 10^{3} m$
I. $3.40 × 10^{3} m$
J. $4.78 × 10^{3} m$
Answer: E
The projection lens of a slide projector has a focal length of $f'=-f=75mm$. When the screen is moved from $8m$ to $10m$, how much does the lens need to be moved?

Options:
A. The lens should be moved $0.16mm$ to the right.
B. The lens needs to be moved $0.14mm$ to the left.
C. The lens requires a $0.20mm$ movement downwards.
D. The lens needs to be shifted $0.11mm$ to the left.
E. The lens needs to be moved $0.20mm$ to the left.
F. The lens needs to be adjusted $0.14mm$ upwards.
G. The lens needs to be moved $0.14mm$ to the right.
H. The lens needs to be moved $0.20mm$ to the right.
Answer: B
A blazed grating is 260 mm wide, with 300 grooves per millimeter, and a blaze angle of $77°122'$. What is the free spectral range of the grating?

Options:
A. 40.8nm
B. 45.3nm
C. 43.6nm
D. 34.2nm
E. 41.2nm
F. 38.5nm
G. 29.1nm
H. 35.5nm
I. 27.8nm
J. 32.7nm
Answer: F
To enable the photographic film in a camera to resolve a line spacing of 2 micrometers, what is the minimum resolving power of the film in lines per millimeter?

Options:
A. 400 lines per millimeter
B. 1000 lines per millimeter
C. 700 lines per millimeter
D. 1100 lines per millimeter
E. 900 lines per millimeter
F. 800 lines per millimeter
G. 300 lines per millimeter
H. 600 lines per millimeter
I. 200 lines per millimeter
J. 500 lines per millimeter
Answer: J
Due to the limitations of diffraction effects, what is the maximum distance at which a person can distinguish the two front headlights of a car? (Assume the distance between the two headlights is 1.22 meters.)

Options:
A. 3.954 km
B. 6.782 km
C. 3.636 km
D. 5.303 km
E. 3.289 km
F. 3.419 km
G. 2.945 km
H. 4.121 km
I. 1.888 km
J. 4.899 km
Answer: C
Given a uniform medium with an absorption coefficient of $0.32 cm^{−1}$, what is the thickness of the medium when the transmitted light intensity is 0.1, 0.2, and 0.5 times the incident light intensity, respectively?

Options:
A. 6.50cm, 4.83cm and 3.77cm
B. 7.40cm, 5.43cm and 2.97cm
C. 7.20cm, 5.03cm and 2.17cm
D. 8.30cm, 5.43cm and 2.67cm
E. 7.60cm, 5.23cm and 3.07cm
F. 7.10cm, 4.93cm and 2.37cm
G. 5.80cm, 4.23cm and 3.97cm
H. 6.90cm, 5.13cm and 3.27cm
I. 7.50cm, 5.33cm and 3.27cm
J. 6.20cm, 5.03cm and 3.57cm
Answer: C
The angular distance that separates two spectral lines with a wavelength difference of ____ is known as angular dispersion.

Options:
A. 0.2nm
B. 1.5nm
C. 0.3nm
D. 1.0nm
E. 0.9nm
F. 2.0nm
G. 1.8nm
H. 0.5nm
I. 0.1nm
J. 0.6nm
Answer: I
Which of the following conclusions is correct for a beam under different loading and constraint conditions?

Options:
A. If the bending moment diagram of the beam is the same, but the constraint conditions are different, then its deformation energy will also be different.
B. If the loading conditions are varied, the deflection pattern remains unchanged regardless of constraints.
C. If the constraint conditions are identical, the shear force diagram will also be the same.
D. If the bending moment diagram changes, the constraint conditions will not affect the deflection.
E. If the beam length is changed, the constraint conditions are irrelevant to deformation energy.
F. If the beam's cross-section is modified, the bending moment diagram will not be affected.
G. If the beam material is altered, the bending moment diagram will remain constant.
H. If the constraint conditions are altered, the loading conditions will determine the bending moment.
I. If the loading conditions are identical, the deformation energy will remain constant regardless of constraints.
J. If the shear force diagram of the beam is identical, then the stress distribution will be the same.
Answer: A
Which of the following descriptions of forced hyperelastic deformation or ordinary hyperelastic deformation is correct?

Options:
A. The mechanical properties result from ionic interactions primarily.
B. The thermal adaptation is influenced by dipole moments extensively.
C. The physical response is governed by Van der Waals forces mostly.
D. The atomic arrangement is stabilized by covalent bonding solely.
E. The molecular structure of both is due to hydrogen bonding patterns.
F. The dual-phase behavior is characterized by metallic bonding elements.
G. The elasticity is driven by enthalpy variations within macromolecular chains.
H. The resilient behavior is determined by entropy changes in polymeric structures.
I. Which of the following descriptions of forced hyperelastic deformation or ordinary hyperelastic deformation is correct?
The molecular mechanism of both deformations is the movement of polymer segments
J. The stress-strain relationship is dictated by crystalline lattice shifts.
Answer: I
When an ideal elastic body deforms, which parameter remains constant?

Options:
A. Magnetic induction
B. Tensile strength
C. Angular velocity
D. Gravitational force
E. Structural volume
F. Sound intensity
G. Thermal conductivity
H. Chemical potential
I. Electrical resistance
J. Internal energy
Answer: J
What are the three types of gas flotation separation methods?

Options:
A. Chemical absorption, mist separation, and emulsion resolving.
B. Molecular diffusion, coagulation flotation, and solvation dynamics.
C. Ion flotation, precipitate flotation, and solvent sublation.
D. Gas absorption, bubble separation, and solution skimming.
E. Elemental filtration, dust flotation, and osmotic sifting.
F. Atomic sorting, foam fractionation, and solvent diffusion.
G. Ion exchange, particle flotation, and solvent extraction.
H. Vapour condensation, froth flotation, and liquid partitioning.
I. Ionic bonding, sediment flotation, and solute sublimation.
J. Compound dissolution, floc flotation, and phase isolation.
Answer: C
What is the core of materials science?

Options:
A. Heat treatment techniques
B. Surface coating processes
C. Magnetic domain behaviors
D. Mechanical durability tests
E. Basic principles of alloying
F. Crystal lattice arrangements
G. Polymer molecular structures
H. Elastic tensile properties
I. Semiconductors fabrication
J. Optical fiber communications
Answer: E
Which of the following dispersed systems exhibits the strongest Tyndall effect?

Options:
A. Iron sol
B. Mercury sol
C. Copper sol
D. Platinum sol
E. Nickel sol
F. Silver sol
G. Tin sol
H. Gold sol
I. Zinc sol
J. Lead sol
Answer: H
When a binary alloy is at a low eutectic temperature, what is the degree of freedom of the system?

Options:
A. 0
B. 8
C. 5
D. 7
E. 1
F. 4
G. 2
H. 3
I. 6
J. 9
Answer: A
Among the following oxides, which one is the easiest to reduce under blast furnace smelting conditions?

Options:
A. MgO
B. ZnO
C. CoO
D. Na2O
E. AlO
F. Li2O
G. NiO
H. K2O
I. FeO
J. CaO
Answer: I
Indicators of pre-furnace operation are: iron output positive rate; iron pass rate; iron quantity difference; ____.

Options:
A. slag fluidity ratio
B. molten metal overflow
C. carbon monoxide emission rate
D. oxygen leakage frequency
E. furnace temperature consistency
F. gas coolant temperature
G. air filtration system effectiveness
H. ventilation system efficiency
I. full-air plugging rate
J. steam pressure oscillation
Answer: I
The effect of 1g/m3 humidity on wind temperature is equivalent to about ___.

Options:
A. 12°C
B. 18°C
C. 30°C
D. 20°C
E. 6°C
F. 25°C
G. 0°C
H. 10°C
I. 15°C
J. 8°C
Answer: E
In order to cause some of the components to form an insoluble compound precipitation,for the wet chemical method or high temperature method to obtain powder materials, according to the different users, the product is required to have a certain ( ), ( ), and ( ), and sometimes even required to be ( ).

Options:
A. elemental purity, geometric symmetry, compositional uniformity, polyphase structure
B. chemical hardness, density levels, binding capacity, amorphous matrix
C. molecular weight, thermal stability, polymer blend, single phase
D. color density, shape regularity, particle consistency, polycrystalline
E. chemical reactivity, surface smoothness, blend uniformity, multi-phase
F. particle size, crystal orientation, particle distribution, amorphous structure
G. elasticity level, brightness scale, filament spacing, crystal lattice
H. particle size, particle shape, particle size composition, single crystal
I. molecular weight, particulate form, aggregation rate, crystalline shape
J. molecular formula, cellular density, composite structure, nonlinear texture
Answer: H
The main factors affecting the purification effect in the process of melting are ( ) and ( ).

Options:
A. temperature, alloy additives
B. heat, atmospheric conditions
C. temperature, crude metal composition
D. pressure, crude metal composition
E. heat, crude metal composition
F. pressure, alloy additives
G. pressure, atmospheric conditions
H. temperature, atmospheric conditions
I. pressure, furnace design
J. heat, alloy additives
Answer: C
Elements such as (), (), () are surface active substances of liquid iron.

Options:
A. N, O, Cl
B. H, O, S
C. C, N, O
D. C, H, O
E. P, S, O
F. C, H, S
G. H, O, N
H. Fe, O, S
I. N, O, S
J. N, O, P
Answer: I
To obtain the oxides of iron, it is necessary to roast under ( ).

Options:
A. freezing temperature (<0°C)
B. room temperature (20-25°C)
C. mild temperature (100-200°C)
D. higher temperature (>800°C)
E. slight temperature (300-400°C)
F. lower temperature (<800°C)
G. warm temperature (250-300°C)
H. cool temperature (10-15°C)
I. elevated temperature (700-800°C)
J. moderate temperature (500-600°C)
Answer: D
The main oxides of most non-ferrous metallurgical slag and steel slag are ( ), ( ), ( ).

Options:
A. H2O, CO2, SO2
B. SiO2, MgO, Al2O3
C. SiO2, Al2O3, Fe
D. MgO, CaO, Fe2O3
E. MgO, Al2O3, K2O
F. CuO, Al2O3, SiO2
G. Fe, CaO, MgO
H. FeO, CaO, SiO2
I. CuO, ZnO, MgO
J. CuO, FeO, Al2O3
Answer: H
The process of ionizing a metal and stabilizing it in solution by adding an appropriate solvent to dissolve the mineral is ( ).

Options:
A. solution stabilization
B. solvent ionization
C. solvent mixing
D. solvent treatment
E. chemical bonding
F. mineral dissolution
G. metal ionization
H. leaching process
I. dissolution method
J. solvent infusion
Answer: H
When the furnace temperature is normal and the molten iron is flowing well, can the iron tap hole be ()?

Options:
A. Constricted
B. No requirements
C. Smaller
D. Elevated
E. Unchanged
F. Increased
G. Larger
H. Lowered
I. Expansive
J. Lessened
Answer: C
Generally, how much should the oxygen content in blast air be increased, so that the tuyere area should be reduced by 1.0%~1.4%?

Options:
A. 1.5%
B. 3.0%
C. 1.0%
D. 1.2%
E. 3.5%
F. 2.0%
G. 1.9%
H. 1.8%
I. 0.5%
J. 2.5%
Answer: C
Kirchhoff's law states that an object that is good at radiation is also good at () the absorption rate of the actual object is always (), and at the same temperature, the blackbody has the radiation force of ().

Options:
A. Absorption, minimum, maximum
B. Absorption, minimum, minimum
C. Reflection, minimum, minimum
D. Emission, minimum, minimum
E. Emission, maximum, maximum
F. Transmission, maximum, minimum
G. Reflection, maximum, maximum
H. Absorption, maximum, maximum
Answer: H
Natural convection of water, forced convection of air and boiling of oil, which of these three cases has the lowest value of convective heat transfer coefficient?

Options:
A. Natural convection of oil
B. Forced convection of helium
C. Boiling of water
D. Natural radiation of
E. Boiling of oil
F. Forced radiation of air
G. Forced convection of air
H. Natural convection of water
I. Forced convection of water
J. Natural convection of helium
Answer: G
Is the directional radiation intensity of the blackbody related to the direction?

Options:
A. Is proportional to area
B. Adapts by environment
C. Changes with wavelength
D. Modifies by shape
E. Varies with distance
F. Depends on temperature
G. Relies on material type
H. Have no relation
I. Alters with time
J. Influenced by its mass
Answer: H
The "2" in Type 1-2 shell and tube heat exchanger type means ().

Options:
A. Number of inspection steps
B. Number of control panels
C. Number of service modes
D. Number of cooling stages
E. Number of heat sources
F. Number of bypass valves
G. Number of pipe runs
H. Number of insulation layers
I. Number of design variations
J. Number of exit tubes
Answer: G
Fouling thermal resistance refers to the difference between the heat transfer resistance of () and the heat transfer resistance of ()

Options:
A. Organic heat conductive layer, inorganic heat conductive layer
B. Dirt heat exchange surface, clean heat exchange surface
C. Unprocessed heat reduction layer, processed heat reduction layer
D. Initial heat dispersion surface, altered heat dispersion surface
E. Basic thermal interface material, enhanced thermal interface material
F. Smooth heat absorption panel, rough heat absorption panel
G. Open heat transfer mechanism, closed heat transfer mechanism
H. Clean heat exchange surface, dirt heat exchange surface
I. Solid heat resistance barrier, liquid heat resistance barrier
J. Arid heat absorption interface, humid heat absorption interface
Answer: B
If the heat flux y=1.8kW/m2 during the heat transfer process and the temperature difference between the cold and hot fluids is 30°C, the heat transfer coefficient is (), and the total heat transfer resistance per unit area is ().

Options:
A. 50W/(m2·K), 0.018(m2·K)/W
B. 50W/(m2·K), 0.020(m2·K)/W
C. 60W/(m2·K), 0.015(m2·K)/W
D. 45W/(m2·K), 0.022(m2·K)/W
E. 55W/(m2·K), 0.016(m2·K)/W
F. 60W/(m2·K), 0.017(m2·K)/W
G. 60W/(m2·K), 0.020(m2·K)/W
H. 50W/(m2·K), 0.017(m2·K)/W
I. 60W/(m2·K), 0.019(m2·K)/W
J. 50W/(m2·K), 0.019(m2·K)/W
Answer: F
A wire with a diameter of 3mm has a resistance of 2.22x10~30 per meter long. The conductor is wrapped with an insulation layer with a thickness of 1mm and a thermal conductivity of 0.15W/(m·K). The maximum temperature resistance of the insulation layer is 85°C, the ambient temperature is 20°C, and the surface heat transfer coefficient between the air and the outer surface of the insulation layer is 20W/(m2·K). What is the maximum current allowed to pass through the wire at this time?

Options:
A. 84.1A
B. 76.3A
C. 72.9A
D. 92.4A
E. 95.3A
F. 94.5A
G. 67.4A
H. 88.7A
I. 101.2A
J. 83.0A
Answer: H
In a given heat transfer process, if the heat transfer coefficient is doubled, what is the original temperature difference between hot and cold fluids?

Options:
A. Tripled by half
B. Constant
C. Unchanged
D. Decreases quadrupled
E. Doubles
F. Quadrupled
G. Increased by half
H. Half
I. Triples
J. Constantly doubled
Answer: H
If the heat flux measured through a 50mm thick large board is 40W/m2, and the surface temperatures on both sides of the board are 40°C and 20°C, the thermal conductivity of the board is (); If the heating heat flux is increased to 80W/m2 and the surface temperature of one side of the board is 25°C, the surface temperature of the other side should be ().

Options:
A. 0.1W/(m.K), 60°C
B. 0.2W/(m.K), 45°C
C. 0.15W/(m.K), 50°C
D. 0.05W/(m.K), 75°C
E. 0.2W/(m.K), 70°C
F. 0.1W/(m.K), 65°C
G. 0.1W/(m.K), 50°C
H. 0.1W/(m.K), 55°C
I. 0.15W/(m.K), 55°C
J. 0.1W/(m.K), 70°C
Answer: F
For a pipe with varying diameter, where the small pipe has a diameter d1, and the large pipe has a diameter d2-2d1,the relationship between the Reynolds numbers at the two sections is?

Options:
A. Re1 = 4 Re2
B. Re1 = 1/2Re2
C. Re1 = 0.5 Re2
D. Re1 = Re2/2
E. Re1 = 2 Re2
F. Re1 = 1.5 Re2
G. Re1 = 2.5 Re2
H. Re1 = 3 Re2
I. Re1 = Re2
J. Re1 = Re2/3
Answer: E
When an ideal fluid flows through a pipe and the cross-section suddenly enlarges, the piezometric head in the pressure measurement tube will______.

Options:
A. Remain unchanged
B. Only remain level
C. Sharply drop
D. Temporarily fluctuate
E. Only rise
F. Instantly stabilize
G. Slowly diminish
H. Gradually decrease
I. Slightly increase
J. Only fall
Answer: E
What are the conditions for determining whether a thermodynamic process is reversible?

Options:
A. Rapid equilibrium process with minimal friction effects
B. Dynamic equilibrium process with negligible entropy changes
C. Fast-moving process with no entropy production
D. Dynamic equilibrium process with no energy dissipation
E. Continuous equilibrium condition with no entropy changes
F. Constant equilibrium process with no external energy
G. Fast equilibrium process with negligible friction effects
H. Quasi-equilibrium process with no dissipative effect
I. Static equilibrium with minimal energy losses
J. Static equilibrium setup with significant energy dissipation
Answer: H
How does the existence of clearance of piston compressor change the theoretical work of volume and working fluid consumption?

Options:
A. The volumetric efficiency is reduced, and the theoretical work consumed by the unit mass working medium is reduced
B. The volumetric efficiency is unchanged, and the theoretical work consumed per unit mass of working medium is increased
C. The volumetric efficiency is increased, and the theoretical work consumed by the unit mass working medium is reduced
D. The volumetric efficiency is increased, and the theoretical work consumed per unit mass of working medium is unchanged
E. The volumetric efficiency is increased, and the theoretical work consumed by the unit mass working medium is increased
F. The volumetric efficiency is decreased, and the theoretical work consumed by the unit mass working medium is reduced
G. The volumetric efficiency is reduced, and the theoretical work consumed by the unit mass working medium is unchanged
H. The volumetric efficiency is unchanged, and the theoretical work consumed by the unit mass working medium is decreased
I. The volumetric efficiency is unchanged, and the theoretical work consumed per unit mass of working medium is reduced
J. The volumetric efficiency is unchanged, and the theoretical work consumed per unit mass E mass is also unchanged
Answer: G
The main reason to improve the cycle thermal efficiency of constant volume heating internal combustion engine is () limited.

Options:
A. Reduce the intake valve size
B. Decrease the engine displacement size
C. Increase the fuel injection pressure
D. Reduce the fuel consumption rate
E. Reduce the engine output torque
F. Increase the ignition timing delay
G. Decrease the compression ratio
H. Decrease the ignition timing advance
I. Increase the exhaust valve size
J. Increase the compression ratio
Answer: J
How many stages are generally involved in the combustion process of a diesel engine?

Options:
A. 9
B. 10
C. 3
D. 8
E. 5
F. 6
G. 2
H. 7
I. 11
J. 4
Answer: J
What are the main engine exhaust pollutants?

Options:
A. Carbon dioxide, methane emissions
B. Hydrocarbons, nitrogen oxides
C. Carbon monoxide, helium
D. Sulfur dioxide, ozone particles
E. Ozone particles, helium emissions
F. Methane, argon emissions
G. Carbon monoxide, methane
H. Carbon dioxide, sulfur dioxide
I. Sulfur dioxide, argon emissions
J. Methane particles, nitrogen oxides
Answer: B
Flywheel edge of the side of the mark indicating that the cylinder piston is located in the upper stop, used as a basis for adjusting and checking ().

Options:
A. Tyre alignment, wheel balancing
B. Exhaust manifold, radiator
C. Brake pads, fluid levels
D. Headlights alignment, wipers
E. Air filter, spark plug
F. Cabin air filter, odometer
G. Oil pressure, battery charge
H. Fuel injector, timing belt
I. Suspension system, driveshaft
J. Gas distribution, ignition
Answer: J
The working substance goes through a cycle and returns to its initial state. What remains unchanged?

Options:
A. Temperature
B. Work
C. Heat
D. A+B+C
E. Volume
F. Mass
G. Enthalpy
H. Pressure
I. Entropy
J. Density
Answer: G
The medium to achieve thermal work conversion is called ()

Options:
A. Heat transfer
B. Gas
C. Energy source
D. Heat engine
E. Steam
F. Working medium
G. System
H. Thermal fluid
I. Mechanical process
J. Power cycle
Answer: F
In any irreversible process, the entropy of the system ()

Options:
A. Not necessarily
B. Initially decreases
C. Spontaneously oscillates
D. No change
E. Reduction
F. Rapidly escalates
G. Always decreases
H. Temporarily stabilizes
I. Eventually vanishes
J. Increase
Answer: A
For the reverse Carnot refrigeration cycle, the greater the temperature difference between the cold and heat sources, the refrigeration coefficient (). Under the same conditions of the highest operating temperature and the lowest temperature system, the refrigeration coefficient of the steam compression refrigeration cycle is higher than that of the reverse Carnot cycle (), and the refrigeration coefficient of the cycle is higher than that of the air compression refrigeration ().

Options:
A. The smaller, the greater, the smaller
B. The same, the greater, the greater
C. The bigger, the smaller, the greater
D. The same, the same, the same
E. The greater, the smaller, the smaller
F. The greater, the greater, the greater
G. The same, the greater, the bigger
H. The smaller, the greater, the bigger
I. The smaller, the smaller, the bigger
J. The greater, the greater, the smaller
Answer: I
Condensation must occur at the saturation temperature of () or () vapor state material.

Options:
A. A value greater than or equivalent to
B. A temperature above or equal to
C. Equal to or significantly
D. Just above or near
E. Substantially higher than
F. Both hotter and colder than
G. Equal to or less than
H. Higher than or close to
I. Lower than or exactly equal to
J. Close to or surpassing
Answer: G
1kg nitrogen from the initial state
$p_{1}=0. 4 5 \mathrm{M P a}$ ,$t_{1}=3 7^{\circ} \mathrm{C}$
By adiabatic throttle pressure change to $p_{2}=0. 1 1 \mathrm{M P a}$ .
environment temperature ambient temperature
$t_{0}=1 7^{\circ} \mathrm{C}$
Find: Hatake loss in throttling process

Options:
A. 121.22KJ
B. 132.75KJ
C. 123.45KJ
D. 134.58KJ
E. 142.00KJ
F. 127.18KJ
G. 115.90KJ
H. 150.00KJ
I. 118.21KJ
J. 124.36KJ
Answer: A
The working medium should have good () and ()

Options:
A. Density/flexibility
B. Conductivity/lightness
C. High temperature resistance/thermal conductivity
D. Fluidity/expansibility
E. Durability/renewability
F. High pressure resistance/purity
G. Malleability/safety
H. Stability/reusability
I. Corrosion resistance/not easy to deform
J. Viscosity/elasticity
Answer: D
Three-phase bridge inverter circuit, thyristor phase shifting occurs between the upper and lower switches on the same bridge arm, what is this called?

Options:
A. 360-degree conduction type.
B. 270-degree conduction type.
C. 210-degree conduction type.
D. 300-degree conduction type.
E. 150-degree conduction type.
F. 330-degree conduction type.
G. 120-degree conduction type.
H. 180-degree conduction type.
I. 90-degree conduction type.
J. 240-degree conduction type.
Answer: H
In a complex circuit, when using Thevenin's theorem to simplify the circuit, if the Thevenin resistance is zero, what does this mean?

Options:
A. There is an ideal voltage source in the circuit
B. There is a total voltage breakdown in the circuit
C. The circuit behaves like an infinite resistor
D. There is an ideal current source in the circuit
E. The power supply is short-circuited
F. The circuit contains only resistive elements
G. There is a disconnected component within the circuit
H. There is a perfect conductive wire in the circuit
I. The circuit operates as an ideal capacitor
J. The power supply is open-circuited
Answer: D
In a linear circuit, when the voltage source is not working, () can be used instead of the voltage source.

Options:
A. Manual switch component
B. Ideal current source
C. Parallel resistance network
D. Ideal voltage source line
E. Constant power supplier
F. Regular voltage inverter
G. Variable resistor element
H. Open circuit
I. Series capacitor lineup
J. Short circuit
Answer: J
For a three-phase transformer in star-delta (Y-Δ) connection, assuming the primary side star connection phase voltage is 230 V, the turns ratio is 2:1, and the secondary side line voltage is__.

Options:
A. 360 V
B. 420 V
C. 290 V
D. 550 V
E. 400 V
F. 600 V
G. 460 V
H. 500 V
I. 230 V
J. 660 V
Answer: G
In the symmetrical component analysis of a multiphase power system, if the zero-sequence impedance of the system is larger than the positive-sequence impedance, what does this usually indicate in the system?

Options:
A. There is an open circuit in one phase
B. The inductive loads are dominant in the system
C. There is a ground fault
D. The three-phase load is unbalanced
E. The power factor of the load is leading
F. The neutral connection is strong and stable
G. Capacitive reactance exceeds inductive reactance
H. The three-phase short-circuit current is small
I. The negative-sequence voltage of the power supply is too high
J. Harmonic distortion is present in the system
Answer: C
The transmission rate of hexadecimal digital signal is 1200B, then the transmission rate is (); If the rate is constant, the octal rate is ().

Options:
A. 3200b/s;3200B
B. 1600b/s;1200B
C. 4800b/s;3200B
D. 1600b/s;2400B
E. 4800b/s;2400B
F. 3200b/s;2400B
G. 1600b/s;3200B
H. 3200b/s;1600B
I. 4800b/s;1600B
Answer: I
AMI codes in line coding solve the () problem, but not the () problem.

Options:
A. Coding Redundancy; Bandwidth
B. Channel Capacity; Signal Decay
C. Intercoder Interference; Noise
D. Signal Strength; Signal Clarity
E. Long Link; Bit Error Rate
F. Longlink 1; Longlink 0
G. Data Loss; Frequency Variation
H. Error Detection; Power Efficiency
I. Bit Error Rate; Error Propagation
J. Transmission Rate; Line Quality
Answer: F
The synchronization that both digital and analog systems may have is ( ) synchronization.

Options:
A. Carrier Wave
B. Frame
C. Transmission Line
D. Signal Path
E. Data Protocol
F. Internet
G. Code Element
H. Frequency Band
I. Control Segment
J. Network Infrastructure
Answer: A
In uniform quantization, the quantization interval (), the quantization signal-to-noise ratio () and the transmission rate ().

Options:
A. Small; big; big
B. Big; Big; Small
C. Big; small; big
D. Small; big; small
E. Big; big; big
F. Big; small; small
G. Small; small; big
H. Small; Small; Small
I. Small; Small; Big
Answer: A
Using multi-base signal to transmit binary sequences can save (), at the cost of ().

Options:
A. Time; Signal-to-Noise Ratio
B. Energy; Bandwidth
C. Bandwidth; Processing Power
D. Bandwidth: Signal-to-Noise Ratio
E. Signal-to-Noise Ratio; Time
F. Time: Complexity
G. Power; Bandwidth
H. Complexity; Energy Efficiency
I. Latency; Bandwidth
J. Power; Complexity
Answer: D
The source code, complement and inverse code of the signed binary number (-1110) are?

Options:
A. 11110,10001,10010
B. 10110,00101,11011
C. 11100,10010,00101
D. 11011,10100,10001
E. 11110,10001,100101
F. 10010,10001,11100
G. 11110,10001,1001011
H. 111101,10001,10010
I. 11110,01101,10100
J. 11101,10011,10100
Answer: A
Extended Synchronization Bus ().

Options:
A. The length of all clock cycles
B. The bus cycle length cannot be changed.
C. All bus cycle lengths
D. No clock cycle division
E. The bus cycle length is always fixed.
F. No Bus Cycle Division
G. The length of the clock cycle cannot be changed.
H. Allow variable clock cycle lengths
I. Allow variable bus cycle length
J. Only fixed-size bus cycles are allowed.
Answer: I
The electric field of an electromagnetic wave propagating in free space has two components $$E_{y}=E_{\mathrm{m}} \operatorname{c o s} \left( \omega t-\beta x \right)$$
and $$E_{z}=E_{\mathrm{m}} \operatorname{s i n} \left( \omega\, t-\beta x \right)$$,and the electromagnetic wave is ().

Options:
A. Linearly polarized wave
B. Radially outward wave
C. Right-handed wave
D. Counter-propagating wave
E. Anti-parallel wave
F. Circularly refracted wave
G. Elliptically Polarized Wave
H. Left-rotating wave
I. Diagonally angled wave
J. Counterclockwise Wave
Answer: C
In resistance-capacitance coupled amplifier circuit at all levels of static operating point (). And can block the zero drift, but not easy to integrate; in the transformer-coupled amplifier circuit, the static operating point of the front stage, the rear stage (), can also block (). Can also be carried out through the transformer turns ratio of the original and secondary sides (), so that the maximum output power on the load.

Options:
A. Independence, non-independence, zero drift, impedance transformation
B. Independence, non-independence, zero drift, current amplification.
C. Not independent, independent, zero drift, voltage amplification
D. Not independent, not independent, zero point drift, impedance transformation.
E. Independence, dependence, zero drift, voltage amplification.
F. Dependency, not independent, zero drift, current amplification
G. Dependence, independence, zero drift, current amplification.
H. Independence, independence, zero drift, voltage amplification.
I. Dependence, Independence, Zero Drift, Voltage Amplification
J. Independence, independence, zero drift, impedance transformation.
Answer: J
When inputs
$$
\overline{{{{I_{0}}}}} \sim\overline{{{{I_{7}}}}}
$$
of the 74LS148 are entered in sequence 11011101, output
$$
\overline{{{Y_{2}}}} \sim\overline{{{Y_{0}}}}
$$
is ( ).

Options:
A. 010
B. 110
C. 111
D. 101
E. 000
F. 100
G. 001
H. 011
Answer: G
A hash table containing 200 table entries is provided, and conflicts are resolved using linear probing, where the average number of control searches to find a table entry when queried by keycode is no more than 1.5, how many table entries should the hash storage space hold? (Let the average search length for a successful search be sm=(1+1/(1-a))/2, where a is the loading factor)

Options:
A. 700
B. 500
C. 676
D. 526
E. 550
F. 450
G. 400
H. 624
I. 350
J. 600
Answer: G