... vậy hãy cho tôi một ví dụ về những điều tôi
làm khiến anh tin như vậy”
Cho vànhậnthôngtinphảnhồi
Cho vànhậnthôngtinphảnhồi là một phần quan trọng trong công tác huấn luyện
và giám ... soát.
Vì phảnhồi có tính chất hai chiều, nên bạn phải cởi mở đón nhận ý kiến phảnhồi
cũng như sẵn sàng đưa ra phản hồi. Không có phảnhồi từ người khác sẽ không thể
có giao tiếp. Và không có ... chung. Việc chovànhậnphảnhồi nên diễn ra suốt giai đoạn huấn
luyện chủ động khi người huấn luyện vànhân viên cùng xác định các vấn đề cần
thực hiện, cùng triển khai kế hoạch hành động và đánh...
... động, qua đó cung cấp cho họ các thông tin
ời lao động, qua đó cung cấp cho họ các thông tin
về tình hình THCV đà qua và các tiềm năng trong t
về tình hình THCV đà qua và các tiềm năng trong ... giá tuỳ thuộc vào bản chất của từng công việc.
phòng sản xuất đà không làm công việc này vì vậy phòng đà không đạt đợc
hiệu quả ĐGTHCV.
3. Thôngtinphảnhồi đối với ngời lao động và bộ phận quản ... tiêu thức trong tiêu chuẩn:
4
4
3. Thôngtinphảnhồi đối với ngời lao động và bộ phận quản lý nguồn
nhân lực:
4
4
II. Yêu cầu đối với hệ thống ĐGTHCV và các lỗi cần tránh trong đánh
giá:
...
... alleviated by adopting
dispersion-shifted or dispersion-flattened fibre [15,16]. Alternatively, semiconductor lasers
oscillating in single longitudinal modes were developed [17,18]. By limiting the spread ... possible FP mode in these grating structures, it is
quite usual to have anti-reflective coatings on the laser facets of DFB and DBR lasers.
The working principle of a uniform-grating DFB laser with perfectly ... K) under continuous wave (CW) operation
was built. Details of coupled wave theory will be covered in the next chapter. Normally in
DFB lasers, the grating period L must be carefully chosen to satisfy...
... second-order corrugation is used.
However, the design of the second-order grating requires a precise control of the grating
parameters. It is shown in the contour map that certain corrugation shapes ... The range of accuracy is extended by
adopting a parabolic model [9] such that
g
peak
¼ aN
2
þ bN þ c ð2:52Þ
where a, b and c are constants determined by fitting the available exact solutions using ... DIODES
where
uðÞ¼
1;>0
0;<0
&
ð2:131Þ
is the unit step function in . By equating eqn (2.120) with (2.130) and setting p ¼ 0, one can
express the harmonic Fourier coefficient as
A
q¼0
¼ A
0
¼...
... equation
within a reasonable range of error. Starting with different initial guesses of ð; Þ
ini
, other
oscillating modes can be determined in a similar way. By collecting all ð
0
;
0
Þ pairs that
satisfy ... particular section. Since the discontinuity caused by
the phase slip is assumed to be very small, the waves in the two sections can be considered to
be continuous at z ¼ 0. In other words,
R
ð1Þ
ðz ... condition on complex analytical functions is satisfied.
Before starting the Newton–Raphson iteration, an initial value of ð; Þ
ini
is chosen from a
selected range of ð; Þ values. Usually, the first...
... the
–continuous change in laser cavity
corrugation period
Tapered corrugation large number – varies along the
–continuous change in laser cavity
corrugation depth g
N-layer surface emitting N ... matching approach, the TMM is more robust and flexible. By converting
the coupled wave equations into a matrix equation, the wave propagating characteristics of
the corrugated DFB section can be represented ... transfer matrices. The differences between them are
also listed.
When the grating height g reduces to zero and the grating period approaches infinity, the
feedback caused by the presence of corrugations...
... the PSP shifts, there is a continuous change in the resonant cavity
formed by the DFB laser such that the actual lasing mode may alter. At ¼ 0:77, it is
interesting to see how all L values converge ... can be seen that a trade-off exists
in selecting the appropriate phase shift value for the optimum values of ÁL and F. On one
hand, phases should be chosen such that the gain margin is large enough ... DCC becomes less efficient. As far as
single-mode stability is concerned, trade-offs exist in selecting the optimum position of
corrugation change and the coupling ratio.
5.4.3 Optimisation of the...
... coefficient ¼ 4 Â 10
3
m
À1
Cavity length L ¼ 500 mm
Optical confinement factor À ¼ 0:35
Grating period à ¼ 227:039 nm
Grating phase at the left facet in rad
Bragg wavelength !
B
¼ 2Ã=n
0
¼ 1:55 mm
Threshold ... refractive
index at threshold can be found to be
n
th
¼ n
ini
þ À
@n
@N
N
th
ð6:18Þ
By substituting ¼
th
in eqn (6.5) at the threshold condition, the threshold wavelength !
th
can be obtained
!
th
¼
2p!
B
n
th
þ ... the 3PS laser structure, a longitudinal variation of
the coupling coefficient is introduced. Discontinuities associated with both the phase shift
and the corrugation change enhance the spontaneous...
... parameters used are listed in the inset. As with the QWS laser structure, distinct
peaks which correspond to different oscillating modes are observed along the spectrum.
When the biasing current increases, ... Á
NN
becomes
influential.
By adopting a longitudinally dependent coupling coefficient , the gain margin and the
field uniformity of the DCC þ QWS DFB LD are improved. Continuous tuning as far as
0.16 ... is assumed for a 500 mm length cavity.
For each oscillating mode shown in Fig. 7.2, the cross and the black circle correspond to the
oscillating mode at threshold and at 5I
th
, respectively. When...
... element in the connecting matrix is unity only if a connection allows a
pulse to travel from port i of node m to port j of node n. In the example given in Fig. 8.3, the
connecting matrix C may be ... case,
Kirchoff’s law can be applied, which is nothing more than a special case of Maxwell’s
equations [7–8]. Strictly speaking, laser devices have dimensions in the order of the
operating wavelength, ... and
terminal loads. The voltage pulses then enter the phase stubs to be delayed before they
continue propagating along the main transmission line. The three-port circulator at the left
facet (section...
... grating modulation. This can be decomposed into a number of
sinusoidal gratings at harmonics of the grating period by Fourier techniques. One of these
harmonics models the real device’s grating ... period of the DFB grating on the
real device, the number of sections and hence the computational task would be excessive.
However, it is possible to represent an odd number of grating periods with ... example, the coupling of each period of the square grating has to be
increased by a factor of five over the coupling of the real laser’s grating to compensate. A
simpler and much neater rule is...
... P
Á
E
R
z
À
ÀÁ
E
S
z
À
ÀÁ
"#
ð10:42Þ
where P
is the phase discontinuity matrix, which causes the complex electric field delay
of at z ¼ z
. By applying the phase discontinuity to eqn (10.26) and following the steps
below ... equations are also discussed in detail. By converting the
coupled wave equations into a matrix equation, these transfer matrices can represent the
wave propagating characteristics of DFB structures. Therefore, ... replacing one or both of the
discrete laser mirrors with a passive grating reflector as shown in Fig. 10.21. By definition,
the grating reflectors are formed along a passive waveguide section, so one...