Exeley Inc.

TÓTH, Mária Erdélyiné

PLUZSIK, Anikó

PLUZSIK, Tamás

MORLIN, Bálint

EXPERIMENTAL INVESTIGATIONS OF PULL-OUT BEHAVIOUR OF SYNTHETIC FIBRES

SANNI-ANIBIRE, Muizz O.

MAHMOUD, Abubakar S.

HASSANAIN, Mohammad A.

ALMUTAIRI, Faleh

HEALTH AND SAFETY PERCEPTION OF CONSTRUCTION WORKERS IN SAUDI ARABIA

Bura, Maciej

Łagiedo-Żelazowska, Małgorzata

Michalak, Michał

Sikora, Jan

Mozer-Lisewska, Iwona

Polish Journal of Microbiology
2018,  Vol. 67,  No 1,  113–115
SHORT COMMUNICATION
* Corresponding author: M. Bura, Department of Infectious Diseases, Hepatology and Acquired Immunodeficiencies, Poznan Uni-
versity of Medical Sciences, Poland, e-mail: mbura@umed.poznan.pl
The prevalence of hepatitis E virus (HEV) infec-
tions in Central Europe has been described only par-
tially and few studies report such data for this part of 
the European continent (Lapa et al., 2015). The knowl-
edge of this subject in Poland is limited to two reports 
discussing the seroprevalence of IgG antibodies in 
182 patients from Poznan center (anti-HEV-positivity in 
15.9% patients, EIA-gen HEV IgG kits; Adaltis, Milano, 
Italy) (Bura et al., 2015) and in 1016 hunters from all 
16 Polish provinces (anti-HEV detected in 20.3% par-
ticipants with ELISA recomWell HEV IgG kits; Micro-
gen, Neuried, Germany) (Sadkowska-Todys et al., 2015).
For another primary hepatotropic virus transmit-
ted by the fecal-oral route, that is, hepatitis A virus 
(HAV), in the 21st century, Poland has experienced 
a  shift toward very low endemicity (Magdzik and 
Czarkowski, 2004) and is currently one of the coun-
tries with the lowest hepatitis A incidence among the 
European Union member states (European Centre for 
Disease Prevention and Control, 2014).
A comparative study of HAV and HEV exposure 
markers (the presence of IgG antibodies against respec-
tive viruses) in 110 randomly selected healthy (HBV, 
HCV, HIV and syphilis-negative; no jaundice in the 
past) unpaid voluntary blood donors (BDs; 75 men 
and 35 women) living in Wielkopolska Region (Greater 
Poland; one of the largest regions in Poland, located in 
the west-central part of our country) was performed. 
The BDs were 19–58 years of age (38.4 ± 9.6; median 
age – 40 years).
Anti-HAV IgG (anti-HAV) seroprevalence was deter- 
 mined by a chemiluminescent microparticle immuno-
assay (CMIA; ARCHITECT HAV Ab-IgG kits; Abbott 
Laboratories, Wiesbaden, Germany) whereas for 
anti-HEV IgG (anti-HEV) WANTAI HEV-IgG ELISA 
kits (Wantai Biological Pharmacy Enterprise, Beijing, 
China) were used, both according to the manufac-
turers’ instructions. These tests are accepted diagnos-
tic tools for the assessment of exposure to HAV and 
HEV, respectively.
The serum samples were collected at the Regional 
Blood Center in Poznan, Poland, during the first 
6 months of 2015 and were stored at –20°C prior to 
testing.
All the BDs gave their written informed consent. 
The study was approved by the local Bioethics Com-
mittee (reference number: 263/15) and was funded 
by Poznan University of Medical Sciences (number of 
funds: 502-01-02205314-04519).
Numerical data were presented as mean and stand-
ard deviation. The comparison of age was performed 
by t-Student test. The assumption if data follow normal 
Comparative Seroprevalence of Hepatitis A And E Viruses in Blood Donors
from Wielkopolska Region, West-Central Poland
MACIEJ BURA1*, MAŁGORZATA ŁAGIEDO-ŻELAZOWSKA2, MICHAŁ MICHALAK3,
JAN SIKORA2 and IWONA MOZER-LISEWSKA1
1 Department of Infectious Diseases, Hepatology and Acquired Immunodeficiencies,
Poznan University of Medical Sciences, Poland 
2 Department of Immunology, Chair of Clinical Immunology, Poznan University of Medical Sciences, Poland
3 Department of Computer Science and Statistics, Poznan University of Medical Sciences, Poland
Submitted 22 January 2017, revised and accepted 28 November 2017
A b s t r a c t
The objective of the present study was to investigate the seroprevalence of HAV and HEV in Polish blood donors (BDs). One hundred and 
ten randomly selected healthy BDs, living in Wielkopolska Region were tested for anti-HAV IgG and anti-HEV IgG with commercial assays. 
The seroprevalence of anti-HAV was 11.8%; anti-HEV were detected in 60.9% of BDs (p < 0.0001). Consumption of risky food was more 
common in anti-HEV-positive BDs (59.1% vs. 33.3%; p = 0.01). Twelve out of 20 BDs (60%) with no history of travel abroad were exposed 
to HEV. Wielkopolska Region, Poland should be regarded as a new HEV infection-hyperendemic area in Europe.
K e y  w o r d s: blood donors, HAV, HEV, Poland, seroprevalence
Bura M. et al. 1114
distribution was checked by Shapiro-Wilk’s test. The 
homogeneity of variances was checked by Levene’s test. 
Nominal data were compared by Chi-square test of inde-
pendence. For the factors that might influence the HEV 
seroprevalence odds ratios (OR) and 95% confidence 
intervals (CI) were calculated. Statistical analysis was 
performed with Statistica 12 (Statsoft, Inc.) software.
All tests were considered significant at p < 0.05.
The seroprevalence of anti-HAV was 11.8% (13/110), 
whereas anti-HEV were detected in 60.9% of BDs 
(67/110) (p < 0.0001); in 2 cases a borderline HEV anti-
bodies testing result was found and included as negative 
in further analysis.
The distribution of combined HAV and HEV IgG 
assessment results was as follows: double (anti-HAV/
anti-HEV) positive – 5 persons (4.5%), only anti-HAV-
positive – 8 BDs (7.3%), double negatives – 35 partici-
pants (31.8%) and only anti-HEV-positive – 62 persons 
(56.4%).
Anti-HAV-positive BDs were older (46.7 ± 6.8 years, 
range 38–58) than seronegatives (37.2 ± 9.4 years, range 
19–58) (p = 0.0006). 
For anti-HAV positive samples the mean ±SD rela-
tive light units (RLU) signal/cut off (s/co) ratio value was 
11.03 ± 3.16 (range 4.12–14.47; the positive result was 
defined as RLU s/co > 1.00) and for anti-HEV positive 
samples the mean optical density/cut off (OD/co) ratio 
value was 5.932 ± 3.454 (range 1.221–14.458; the positive 
result was defined as OD/co > 1.100; values between 0.9 
and 1.100 were considered borderline); it is worth to 
know that in only 9 HEV seropositive persons (13.4% 
out of all HEV-positive BDs) the OD/co ratio was lower 
than 2.000. The prevalence of some variables in relation 
to anti-HEV IgG status is shown in the Table I.
The main conclusion from the above analysis is that 
the culinary habits indicating the consumption of some 
risky food (raw / undercooked meat or seafood) were 
more common in the BDs exposed to HEV. This factor 
has been recognized as the source of infections with the 
zoonotic genotypes of the virus (Said et al., 2009; Man-
suy et al., 2011; Guillois et al., 2013; Meng, 2013). In 
addition, a trend toward a more frequent prevalence of 
anti-HAV in HEV-seronegative (vs HEV-seropositive) 
BDs in conjunction with a significantly less common 
presence of HAV exposure marker among the study 
participants suggest that the main modes of transmis-
sion for these viruses in our region are different.
Although there was no mean age difference between 
the study participants exposed to HEV and anti-HEV-
negatives (in our opinion, it was only because the group 
of BDs was small), the number of HEV-seropositive 
BDs aged > 30 tended to be higher than the prevalence 
of these antibodies in younger persons (see Table I). 
An evident relationship between the seroprevalence 
of HEV and age is reported in most available studies 
among BDs (Dreier and Juhl, 2014).
It should be stressed that in case of 20 persons 
with no history of travel abroad anti-HEV positivity 
was found in 60% of them (n = 12). It supports some 
previous suggestions (Bura et al., 2015) that autochtho-
nous (locally acquired) HEV infections do occur also 
in Poland.
Despite an obvious limitation of this study, that is, 
a small number of participants, its results are surpris-
ing because they indicate that Wielkopolska Region is 
a hyperendemic area for HEV infections. In Europe, 
similar seroprevalence of anti-HEV (52.5%) was found 
only in the Toulouse region, southwestern France 
(Mansuy et al., 2011). Such a high frequency of HEV-
seropositivity, significantly more important than found 
in previous surveys from our country in specific pop-
ulations (patients of Infectious Diseases Department 
Mean age ± SD [years] 39.5 ± 8.9 36.6 ± 10.3 NAb 0.1198Median age (IQRa) 41 (34 – 46) 37 (27 – 45)
BDs aged > 30 56 (83.6%) 29 (67.4%) 2.46 [0.99–6.09] 0.0523
Men 45 (67.2%) 30 (69.8%) 0.89 [0.39–2.02] 0.7749
Current place of residence – city 55 (82.1%) 35 (81.4%) 1.05 [0.35–3.29] 0.9233
Childhood place of residence – city  46 (69.7%) 29 (67.4%) 0.90 [0.37–2.25] 0.8038
Travel abroad during lifetime 55 (82.1%) 35 (81.4%) 1.05 [0.39–2.82] 0.9266
Contact with swine 12 (17.9%)  8 (19.1%) 0.93 [0.34–2.50] 0.8814
Anti-HAV positivity  5 (7.5%)  8 (18.6%) 2.83 [0.86–9.33] 0.0866
Consumption of raw / 39 (59.1%) 14 (33.3%) 2.89 [1.29–6.48] 0.0100undercooked meat or seafood
Table I
Status of anti-HEV and selected variables in 110 BDs from western Poland.
aIQR – interquartile range; bNA – not assessed.
Variable Anti-HEV+(n = 67)
Anti-HEV –
(n = 43) OR [95% CI] p
Short communication1 115
and hunters) (Bura et al., 2015; Sadkowska-Todys et al., 
2015), can be explained by a very good sensitivity of the 
Wantai assay. Some seroprevalence assessments across 
Europe have shown that the use of these tests can result 
in several times higher ratios of anti-HEV in compari-
son to other manufacturers’ assays (Bendall et al., 2010; 
Mansuy et al., 2011; Wenzel et al., 2013).
Faced with such unexpected data, at least one ques-
tion of fundamental importance must be asked: what is 
the practical significance of such a common occurrence 
of HEV infections in Wielkopolska Region?
The answer is difficult because to the best of our 
knowledge none of the Polish hepatology centers has 
been performing tests for hepatitis E to date and there 
are no data on the prevalence of acute hepatitis of 
unknown etiology neither in our region nor Poland-
wide. Due to a very common subclinical exposure to 
HEV revealed by this study, a potential danger of HEV-
infected blood transfusions, particularly to immuno-
compromised recipients, should also be taken into 
account (Matsubayashi et al., 2004; Hewitt et al., 2014; 
Huzly et al., 2014). This issue should be rapidly clarified. 
In conclusion, the results of the current report sug-
gest that Wielkopolska Region, west-central Poland, 
should be regarded as a new HEV infection-hyperen-
demic area in Europe.
Acknowledgments
We would like to thank Aleksandra Bura for her important tech-
nical support, Dr Michał Chojnicki for valuable rapid transportation 
of BDs’ samples, Alicja Bukowska and Dr Hanna Skalisz from the 
Regional Blood Center in Poznań for their support in the organiza-
tion of the study and collection of blood samples.
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497–500.



Comparative Seroprevalence of Hepatitis A And E Viruses in Blood Donors from Wielkopolska Region, West-Central Poland

Shuping, Xu

Pei, Xu

Qiyu, Dong

Xiaohui, Su

The Portable Gas Analyzer Based on the Spectrum

Shaochang, Wang

Fei, Xu

Weixia, Yang

Zhe, Ma

Application of Greedy Random Adaptive Search Algorithm (GRASP) in Flight Recovery Problem

Wen, Dang

Xinliang, Liu

2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
69 
 
The Comparison on the Side Feed Mode of Micro-strip Patch 
Wen Dang 
Department of Communication and Information 
Xi'an Technology University 
Lane 78, Yanta Road,  
Beilin District, Xian, China 
e-mail: 13637863650@163.com 
 
Xinliang Liu 
Department of Communication and Information 
Xi'an Technology University 
Lane 78, Yanta Road,  
Beilin District, Xian, China 
e-mail: 84829562@qq.com 
 
Abstract—The feeding of the micro-strip patch is flexible and 
complex, especially side feeding. In this paper, a single micro-
strip patch antenna with a center frequency of 2.45GHZ is 
taken as an example to explore the performance of the slotted 
feed and non-slotted feed and verified in HFSS15.0. Combined 
with HFSS15.0 software simulation and theoretical calculation, 
the corresponding conclusions can be obtained. The theoretical 
value and simulation results will be shown that: the required 
1/4 converter sizes of the non-slotted side feed and slotted side 
feed are different. By contrasting with sizes of two feeding 
modes, electrical size of the slotted feed is smaller. It can be 
known that all performances of the slotted feed are more 
superior. 
Keywords-HFSS Simulation; Micro-strip Patch; Side-feed; 
Slot; Matching 
I. INTRODUCTION  
Antenna is a necessary component for radiating and 
receiving radio waves in engineering systems such as 
wireless communications, radio and television, navigation, 
satellite, radar and other engineering systems. The micro-
strip patch is simple and easy to plastic, its feeding modes 
are flexible and changeable. The stability of the antenna can 
be also affected by micro-strip patch feeding mode. The 
different feeding mode has different properties. The design 
of the feeding system determines the current distribution of 
the radiation patch. The more consistent the current direction 
is, the higher the gain is, the greater the energy is, and the 
better the directivity is [3]. Therefore, in an antenna system, 
it is especially important that how the feeding system should 
design, which determines the stability of the system and the 
quality of microwave devices. 
In this paper, two different side feed modes of the 
radiation patch are analyzed and compared. By simulating 
the cell structure of the micro-strip patch antenna with the 
center frequency f at 2.45GHZ in HFSS15.0, the 
corresponding sizes of the 1/4 impedance converter and 
intrinsic impedance are different, when the feeding position 
is not the same place, which has been validated in HFSS15.0. 
The mode following the theoretical sizes calculated by given 
equations is simulated in HFSS15.0. The simulation results 
have been drawn the followings. For the non-slotted side 
feed, the radiation impedance is caused by the edge 
impedance of the patch. The theoretical calculated 1/4 
converter has a large error between the length and width 
values. To achieve the minimum S11 at the center frequency, 
it is necessary to optimize the micro-strip line parameters for 
several times. For the slotted side feed, the radiation 
impedance is produced by the edge impedance of the patch 
and the edge impedance of the groove. The theoretical value 
of the 1/4 converter has a higher accuracy. The best 
performance of the center frequency can be achieved by 
adjusting the width and depth of the slotted feeding. Based 
on the above conditions, the minimum value of the antenna 
S11 can be obtained, the smaller the reflection energy is, the 
greater the transmission efficiency is. 
II. DESIGN AND ANALYSIS OF RADIATION PATCH UNIT 
In this paper, the radiation patch of the center frequency f 
= 2.45GHZ would be used as an example, the thickness h of 
the substrate with Rogers5880 is 1.5mm, its dielectric 
constant is 2.2. According to the formula (1) – (5) [8] - [9] , 
it can  be obtained  that the width w, length L were 40mm 
and 48.4mm  respectively, as well as  the input impedance. 
The width w of radiation patch  is the following: 
2
1
2
1
2






 
 r
f
c
w


Where c is the speed of free space wave. 
Taking into account the edge shortening effect, the actual 
length L of  the radiation patch should be expressed as: 
L
f
c
L
e
 2
2 

Where 
e
 is the effective permittivity, L  is the length 
of the equivalent radiation gap, they can be calculated by 
using the following formulas  respectively.   
2
1
e 121
2
1
2
1












w
hrr 

 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
70 
 
  
  8.0258.0
264.03.0
412.0 e



hw
hw
hL
e


The input impedance can be obtained as following: 

 
)(cos
2
2 z
G
zYin



Where G is the radiation conductance, β is the phase 
constant in the medium, and z is the distance from the feed 
point to the radiation patch edge. It can be concluded that the 
different input impedance can be obtained by selecting 
different feeding point positions. 
A. Radiation Patch Unit  
The length and width of the radiation patch can be 
calculated by formulas (1)-(4). The edge impedance of the 
radiation patch can be obtained by formula (5). The length 
and width of the 1/4 impendence converter can be known by 
the edge impedance. The width and length of the 50Ω 
intrinsic impedance can be also counted. According to the 
optimum sizes, the model can be built in hfss15.0 shown in 
Fig.1. 
 
The size of the slotted micro-strip patch can be also 
calculated by the same method. The optimum sizes can be 
obtained after many optimizations, it can be built in hfss15.0 
shown in Fig.2. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 1. Slotted patch antenna 
After hfss15.0 simulation, the results are obtained in 
TableⅠ. The simulation results obtained by the two feeding 
methods are basically the same. The theoretical sizes of the 
slotted feed is closer to the simulated ones, even almost 
identical, and its electrical size is smaller. When optimizing 
in the way of the slotted feed, the workloads can be greatly 
reduced and the efficiency can be improved. 
B. Verification 
In order to verify the rationality of the above conclusions, 
the  input port can be excited by the wave port with a 50 Ω 
load. when the width of the micro-strip line is w0 and the 
medium thickness is h, the height of the wave port is 
generally set to 6 ~ 10h. When there is w0>h, the width of 
the wave port is set to 10w0. When there is w0 <h, the width 
of the wave port is generally set to 5w0 or 3 ~ 4h [8]. 
According to the rules, it can be built and verified in 
HFSS15.0. The size and impedance of each port are shown 
in TableⅠ. 
From TableⅠ, it can be seen that the impedance value 
can be directly gotten by adding wave-port excitation for the 
converter as the input impedance, after running in hfss15.0. 
The slotted feed mode is closer to the theoretical value than 
the non-slotted feed mode. Thus, the slotted feed mode can 
improve the efficiency of the operation and reduce the 
workload. 
C. Comparison and New Discoveries of Two Feed Modes  
In the micro-strip feed, the return loss can be affected by 
the size of the 1/4 converter. The reflected voltage wave in 
the circuit can be reduced by proper using the 1/4 converter, 
the loss can be also reduced. The different performances of 
slotted and non-slotted feed are shown in TableⅠ. 
 
48.4mm 
40mm 
6mm 
14mm 
10mm 
1mm 
Figure 1.  No slotted patch antenna 
4.62mm 
48.4mm 
40mm 
 
6mm 
4mm 
22.76m 
1
0
m
m
 
Figure 2.  Slotted patch antenna 
 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
71 
 
 
TABLE I.  COMPARISON BETWEEN THE SLOTTED AND NON-SLOTTED FEEDING ( UNIT: MM ) 
 The Slotted  The Non-slotted   
 Optimization Optimization Calculation 
The length of patch 48.4 48.4 48.40 
The wide of patch 40 40 39.70 
 
The port of 1/4 converter 
length 22.76 14 22.76 
wide 2.1 1 2.14 
impedance 82.3Ω 116.2Ω 79.37Ω 
 
The port of 50Ω 
length 4.62 6 4.62Ω 
wide 6 10  
impedance 50.7Ω 42.2Ω 50Ω 
Substrate thickness H 1.5 1.5 1.5 
The wide of the slotted 4   
The length of the slotted 10   
S11 -45.3db -37.9db  
gain 7.89db 7.82db  
Size 2010mm2 1971.516mm2  
bandwidth 1.2% 1.2%  
reduction 2% 
 
From TableⅠ, it can be concluded that the electrical size 
of the slotted feed is slightly smaller than the electrical size 
of the non-slotted feed, in that case where the return loss, the 
gain and bandwidth of the same patch are substantially 
consistent. The theoretical value of the slotted feed size is 
closer to the optimum value. Therefore, when the micro-strip 
arrays are formed, the advantages of the slotted feed are 
more obvious. 
III.  CONCLUSION 
According to comparison and analysis of the simulation 
results of the two feeding methods, the following 
conclusions can be drawn: 
The value of the S11 is closely related with the size of the 
micro-strip line, especially the width of the micro-strip line. 
The impact of the width play important role, the center 
frequency and the ideal value can be coincident by adjusting 
the width. The value of S11 can be made better by adjusting 
the length, So that the feed network can achieve full match. 
The 1/4 converter（ Z1） of the non-slotted feed is 
determined by the micro-strip characteristic impedance (ZL) 
and the edge impedance (ZL) of the patch. Similarly, the 
edge impedance of the slotted feed patch is mainly caused by 
the edge of the slot and the radiation patch. 
The edge impedance and micro-strip line impedance can 
be calculated in HFSS15.0 by directly adding wave port 
excitation. After calculation, the impedance Z0  values can 
be gotten as shown in TableⅠ. 
In short, all performances of the slotted feed are better 
than ones of the non-slotted feed. In the feed mode selection, 
the slotted feed is a relatively stable feeding method. 
IV. THE DEVELOPMENT PROSPECT AND SIGNIFICANCE 
In the paper, by comparing the performances of two 
different feeding methods[11], it could been seen that 
performances of all aspects of slotted feed are even better. 
When the slotted feed is matched, the theoretical value is 
more accurate without too much optimization, saving a lot of 
time and improving the simulation efficiency, which 
provides a good foundation for the micros-trip antenna array. 
The slotted radiation patch reduces the electrical size of the 
patch greatly, so that the antenna structure is more compact 
and miniaturization. This will be the future development 
tendency of micro-strip antennas. 
Today, micro-strip theory is mature and widely used. 
With the wide application and great development of micro-
strip antenna in the fields of satellite communication [5], 
millimeter-wave [4] and mobile communication, the research 
of micro-strip planar antenna technology [10] will become 
one of the hotspots in future antenna research. At present, the 
compact profile of the antenna is a welcomed developed 
tendency [6] - [7]. The sizes of the radiation patch, whether it 
is as a unit patch micro-strip antenna, or as the array antenna 
unit array, affect the antenna resonance point and other 
performances. Stable basic unit structure will be provided 
broadband for the micro-strip patch as  good foundation. 
ACKNOWLEDGEMENT 
I would like to thank all my teachers who have helped me 
to develop the fundamental and essential academic 
competence. My sincere appreciation also goes to all the 
teachers  and students who helped me. 
 
REFERENCES 
[1] S. L. S. Yang, K. F. Lee, and A. A. Kishk, “ Design and study of 
wideband signal feed circularity polarized microstrip antenna, ”  
Progress In Electromagnetics Research, PIER 80, 45–61, 2008 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
72 
 
[2] Huynh, T. and K. F. Lee, “Single-layer single-patch wideband 
microstrip antenna,” Electron. Lett., Vol. 31, No. 16, 1310–1312, Aug. 
1995. 
[3] Bhalla, R. and L. Shafai, “Resonance behavior of single U-slot 
microstrip patch Antenna,” Microwave and Optical Technology 
Letters, Vol. 32, No. 5, 333–335, March 2002. 
[4] Z. Pi and F. Khan, “An introduction to millimeter-wave mobile 
broadband systems,” IEEE Commun. Mag., vol. 49, no. 6, pp. 101–
107, Jun. 2011. 
[5] E. Arnieri, L. Boccia, G. Amendola, and G. Di Massa, “A compact 
high gain antenna for small satellite applications,” IEEE Trans. 
Antennas Propag., vol. 55, no. 2, pp. 277–282, Feb. 2007. 
[6] K. L. Wong, Compact and Broadband Microstrip Antennas. Hoboken, 
NJ: Wiley, 2002. 
[7] S. K. Podilchak, M. Caillet, D. Lee, Y. M. M. Antar, L. Chu, M. 
Hammar, D. Caldwell, and E. Barron, “A compact circularly 
polarized antenna using anarray of folded-shorted patches,” IEEE 
Trans. Antennas Propagation, vol. 61, no. 9, pp. 4861–4867, Sept. 
2013. 
[8] Li Mingyang. Liu Yang.Design of HFSS Antenna [M]. Beijing: 
Electronic Industry Press, 2014. 
[9] John Klaus• Antenna (Third Edition, Volume 1) [M]. Beijing: 
Electronic Industry Press, 2004. 
[10] Deng Weibo. Analysis of characteristics of high frequency monopole 
antenna on dielectric plane [J]. Journal of Electronics & Information 
Technology, 2001,23 (12). 
[11] Li Xiangqiang. Liu Qingxiang. Zhao Liu.et. 3-ring 48-element high 
power radial line helical array antenna. High Power Laser and Partiacl 
Beams. 2006.18(5):843-846. 
 
 
 


The Comparison on the Side Feed Mode of Micro-strip Patch

Chen, Guoshao

Lian, Zhichao

2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
73 
 
The Design and Implementation of Displacement  
Monitoring System for Tailings Dam 
Guoshao Chen 
School of Computer Science and Engineering 
Xi’an Technological University 
Xi’an, 710021, China 
e-mail: 1825247141@qq.com 
Zhichao Lian 
School of Computer Science and Engineering, 
Xi’an Technological University, 
Xi’an, 710021, China 
e-mail: 965941167@qq.com 
 
Abstract—Non-coal mining generally produces a large amount 
of tailings, and tailings usually accumulate in the canyon 
between two mountains, and the downstream of the tailings is 
intercepted by the dam. The dam is called a tailings dam. The 
development of safety monitoring technology for tailings dam 
is accompanied by the history of dam construction. The safety 
of tailings dam is not only related to the normal operation of 
mining industry, but also to the life safety of downstream 
residents. Once the tailings dam break, the loss caused by the 
dam is inestimable. In this paper, the laser collimation system 
is used to monitor the displacement of the dam, and the center 
of light is measured by the center of gravity, and the laser 
beam is reconstructed by a lens. The method has the 
advantages of high accuracy and simultaneous detection of 
horizontal displacement and vertical displacement of tailings 
dam. It is a new monitoring technology for dam displacement 
and has good application prospects. 
Keywords-Dam Displacement; Center of Gravity Method; 
Laser Spot 
I. SUMMARY 
Human beings have begun to develop and use mineral 
resources a long time ago. China has a rich variety of mining 
industries, and the mining industry is the basis of various 
industries. Minerals can't be 100% purity. During the 
smelting process, the impurities in ores are separated. 
Because the value of impurities can be very small, they 
accumulate in tailings. With the improvement of smelting 
technology, the utilization ratio of minerals is becoming 
higher and higher, but there are still some tailings. A tailings 
dam has been formed and the tailings dam is used to prevent 
the dams from tailings. In our country, thousands of such 
tailing dams are standing large and small. The collapse of the 
tailings dam occurred, which caused great loss to the life and 
property of the country and the people, and caused serious 
pollution to the natural environment. In September 8, 1998, a 
special dam break occurred in Linfen, Shanxi, which killed 
254 people and had a very bad impact on the society. In 
September 21, 2010, tin tailing dam of Guangdong Xinyi 
Qian Pai Village in Zijin Mining Co. the dam failure 
occurred, the accident caused 6 people missing, 5 people 
were killed and 7 injured. 
Because of various reasons, many countries have 
occurred dam break in history. In December 2, 1959, the 
French Marce broke down. Because the management failed 
to analyze the dam monitoring data in time, it resulted in a 
disaster that could be avoided. Although the history of 
damming is accompanied by the history of human 
civilization, it has a history of thousands of years. However, 
due to various uncertain factors of the dam body, it is 
difficult to detect the safety of the dam. Early monitoring is 
simply a simple appearance check, and no scientific 
monitoring means. By the middle of twentieth Century, the 
dam safety monitoring theory system was basically formed. 
With the appearance of some monitoring instruments and 
monitoring methods, vertical line method, triangulation 
method and precise leveling method were used to measure 
horizontal displacement and vertical displacement. 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
74 
 
According to the technical code for safety monitoring of 
dam (SL 60-94) promulgated in 1994 and the technical code 
for safety monitoring of concrete dams issued in 2003 
(DL/T5178-2003), dam safety monitoring projects generally 
include the following 5 aspects. 
1) Monitoring of working conditions: also called 
environmental monitoring, mainly including water level, 
water temperature and freezing and so on. 
2) Deformation monitoring: mainly including the 
horizontal displacement of the dam and the vertical 
displacement of the dam. 
3) Water leakage monitoring: mainly including the 
infiltration line of the dam. 
4) Pressure monitoring: mainly including the temperature 
of the dam, the earth pressure and so on. 
5) Other monitoring: mainly including earthquake 
monitoring. 
II. SYSTEM OVERALL DESIGN 
In this paper, the image processing method is used to 
measure the displacement of the dam, and its structure is 
shown in Figure 1
.  
Figure 1. System structure 
The laser and laser receiver are fixed on both sides of the 
mountain. The lens is mounted on the dam body. The laser 
uses a helium neon laser, and the laser emitted from the light 
source is projected to the laser receiver through the lens. The 
laser will form a spot on the receiver. The laser, lens, and 
laser receiver are in the same line in the ideal condition. 
When the dam displacement occurs, it will drive the lens to 
move. The corresponding image is also moving on the laser 
receiver. By measuring the displacement of the spot on the 
detector, we can get the displacement of lens system further. 
 
Figure 2. Monitoring schematic 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
75 
 
Figure 2 is a monitoring schematic. L is a laser, a lens is 
M, and the center of M is O and O ', y and y' as a laser spot 
on the laser receiver. When the lens is at O, the L passes 
through the M imaging at the Y point; when the lens is 
moved to O ', the spot moves to y'. The displacement 
distance of the lens can be calculated by the CCD system, 
which is behind the laser receiver, to collect the 
displacement of the spot. According to the trigonometric 
relationship 
2
1
21
1
)( l
l
xx
x



Assuming that the location of the lens is only moving up 
and down, the length of x1 and x2 is known. As long as we 
can detect the displacement of Y accurately, we can further 
calculate the displacement of the dam. The deformation of 
the dam body can be obtained by measuring the 
displacement of each measuring point installed on the dam 
body. 
The images captured by the CCD camera should be a 
perfect dot in the ideal situation. But in practice, there are 
inevitably some diffraction phenomena, and all kinds of 
other disturbances will be the deformation of the spot, so that 
the ideal center position of the spot will be deviate from the 
actual position. So we must first filter the image collected by 
CCD to carry out the next process. 
III. GRAVITY METHOD 
In this paper, the center of laser spot is extracted by the 
method of center of gravity extraction. When using the 
center of gravity method to deal with the spot, the image is 
first two valued, and then the spot area is identified. The 
accuracy of this method is relatively high and the speed is 
faster. The center of gravity method is only applicable to the 
symmetry pattern. If the image is asymmetrical, there will be 
a lot of deviation. 
The basic principle of the gravity method is to replace the 
geometric center of the image with the energy center of the 
image. The gray value of the pixel of the image is P. The 
center of gravity coordinates are (x, y)  

 

i
ii
p
px
x


 

i
ii
p
py
y

ni ....3,2,1  
In order to improve the reliability of the system, every 
measuring point must be measured several times, and the 
position of the spot can be calculated according to the 
measured data. CCD is repeatedly sampled to get the average 
value, so as to improve the accuracy. 
IV. HARDWARE INTRODUCTION 
The system consists of six parts is shown in figure 3: 
 
 
Figure 3. System hardware 
A. Laser 
The laser has high luminance, very small divergence 
angle and good monochromatic property; because of these 
unique properties, it is used as a quasi straight line in this 
system. 
B. Lens system 
In this system, the beam of laser is reshaped, the quality 
of beam is improved, and the accuracy of measurement is 
improved. Optical lens is used to realize it. In practical 
application, Fresnel Lens is used. 
C. Laser receiver 
The translucent scattering glass similar to the wool glass 
is convenient for the camera to collect the spot of the light 
spot. 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
76 
 
D. Camera 
The receiver module uses the camera, and the application 
of the camera is very common. In this system, it is mainly 
used to accept the laser spot image. 
E. Processor 
An intelligent chip is used to analyze the image, and the 
amount of displacement is calculated. It mainly includes 
hardware design and software design. And the data will be 
sent to the wireless module. 
F. Zigbee wireless module 
The system uses the wireless module to transmit the 
deformable data to the base station, and overcomes the 
difficulty of long distance wiring, and uses the popular 
Zigbee to implement it. Zigbee is a wireless network 
transmission technology which has been developed in recent 
years, which is adaptable to short distance, low rate and low 
power consumption. 
V. CONCLUSION 
In this paper, the dam displacement monitoring system is 
designed in detail, including hardware structure design and 
image processing algorithm. The system is tested in the 
tailings dam, the data is accurate. Due to the transmission of 
laser in the air, the visibility of the air is reduced, the 
brightness of the laser spot is insufficient, so the data cannot 
be collected sometimes. 
ACKNOWLEDGMENT 
Fund support: Shaanxi Education Department Special 
Fund Project number: Shaanxi Education Finance[2013] 23 
 
VI. REFERENCE 
[1] Tailings beach length monitoring system research based on digital 
image processing  Zhang Yulei 
[2] Tailings dam displacement monitoring system based on laser 
collimation method design Ru Naiyu 
[3] Tailings safety monitoring system based on Silverlight Zhang 
Cheng 
[4] High precision positioning algorithm for laser spot center research 
Chen he; Yang Zhihao; Guo pan; Zhang Yinchao; Chen Siying 
Beijing Institute of Technology Journal. 
[5] Astronomical instruments in image tracking algorithm of the 
comparative study of Wang Lili; Hu Chinese; season Hangxin 
astronomy.  
 
 


The Design and Implementation of Displacement Monitoring System for Tailings Dam

Yuanyuan, Wang

2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
104 
 
The Establishment and Implementation of Information Network Security Plan 
Wang Yuanyuan 
Ideological and Political Department 
Xi’an Peihua University 
Xi’an, 710125, China 
e-mail: 64789178@qq.com 
 
Abstract—This paper explains the idea of information security 
and discusses the establishment of the security system of 
information network. By using the information system security 
engineering method, we will establish and improve the network 
security plan and disaster recovery plan through strict 
organization and management, adequate financial support, 
strong talent support and deep technical guarantee. This paper 
puts forward the overall strategic goal of the "people-oriented, 
to prevent the main" network security and the overall plan to 
solve the network security problems. 
Keywords-Information Security; Network Security; Network 
Security Plan 
Information is the main trend of development in 
contemporary society. The rapid development of information 
has a great impact on all aspects of the state and society. The 
information network is the nervous system of the 
information society. As the main infrastructure of 
information communication, the security problem has 
become a new security research hotspot. At present, the 
threat control of network security has been extended from 
the technical level to the management level to a great extent. 
I. AN OVERVIEW OF INFORMATION NETWORK 
SECURITY 
A. The Concept of Information Network Security and The 
Idea of Information Security 
Information network security is a security protection to 
prevent accidents and malicious attacks from the 
confidentiality, integrity, availability, controllability and 
non-repudiation of information itself and information system 
(network structure, application services, etc.). Information 
network security is based on the physical layer and operation 
level of information network system, as well as the 
protection of information itself (data layer) and the level of 
attack (content level). 
The definition of the definition of network security at the 
technical level has been relatively complete. But the security 
of information network is a multi-dimensional, multi factor 
and multi-objective system. The establishment of a security 
system cannot rely solely on a single security mechanism 
and a variety of security services. Access to the security of 
the entire information network system depends on the 
combination of multiple security mechanisms and a variety 
of security services. The concept of information security, 
which was produced in 1990s, is the result of this idea. 
The security system of information security is to ensure 
the security of information system through the combination 
of level and depth protection, active and passive defense. 
The basic components are shown in Figure 1. 
 
Figure 1. Information security system components 
In the system of "human centered", the information 
security system not only attaches importance to the adoption 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
105 
 
of safety protection technology to protect information, but 
also emphasizes "preventive measures". Active defense 
strategy is adopted to improve the ability of intrusion 
detection, vulnerability scanning, virus prevention, 
evaluation and audit, and the ability of rapid response and 
recovery after attack. 
B. The Necessity of the Research on the Security of 
Information Network and the Establishment of the 
Security System 
The development of information network technology has 
accelerated the process of social information. The 
development of information has opened up a broad space for 
the application of the information network system. However, 
because of the irrational decision making for the 
development of technology for many years, the dependence 
of the state and the society and the public on the information 
network has gradually increased. Information network is 
realizing information exchange and sharing. While greatly 
facilitating and enriching social life, network security has 
become an important factor affecting national security and 
social stability due to the vulnerability of network itself and 
human attacks and destruction. 
Therefore, the current government of the world has taken 
information security as the focus of government work. Many 
laws and regulations related to information security have 
been issued. The international organization for 
standardization has also developed a large number of safety 
standards. The information security system in China is also 
under construction. 
According to the goal of information security system in 
China, the design and implementation of information 
network security is comprehensively considered from the 
perspective of personnel, technology, management, 
legislation and operation. We have put forward the 
international safety standards and national security law as a 
guide, the use of information system security engineering 
method, through rigorous management, adequate funding, 
strong talent support, strong technical guarantee, establish 
and improve the network security plan and disaster recovery 
plan. Based on the principle of "people first", we should 
achieve the goal of achieving all levels of safety assurance 
from border security to host safety, and strive to reduce the 
security threat to an acceptable level and effectively control 
risks. In the event of an invasion and other disasters, a full 
range of security strategic objectives with powerful recovery 
and counterattack capabilities are achieved. 
II. NETWORK SECURITY PLAN 
A. Objectives of the Security Plan 
According to the relevant national laws and regulations, 
as well as the strategic objectives of the information network 
security system, the network security plan is formulated. The 
aim is to strengthen the security of network security and 
establish a relatively safe information network environment. 
Through the effective implementation of the plan, the 
following four major goals are achieved: 
1) Establish a solid technical basis. We should educate 
and train technical groups with strong network security 
capabilities, establish relevant organizations, identify and 
improve the responsibilities of security personnel, and 
defend, detect, respond and recover against possible 
infringed networks. 
2) Detection and response. Detection and monitoring of 
network status should be timely. When an attack is found, it 
can react quickly and control the attack, and quickly restore 
or rebuild the normal running state of the network. 
3) Defense and recovery. Establish an efficient network 
defense system. The protection of key infrastructure is free 
from network invasion and virus invasion. Reduce network 
vulnerability. It has strong defense and recovery capabilities 
for network attacks that have occurred and may occur. 
4) The necessary ability to counterattack. The existing 
security defense capability may not be enough to achieve the 
desired security target for the aggressive attack. It is 
necessary to have the ability to fight back, to prevent or even 
destroy the invaders' attempt. 
B. The Main Contents of the Network Security Plan 
The security of information network issystem 
engineering. It not only needs solid technical support, but 
also is restricted by many factors, such as staffing, 
organization construction, management level, national 
legislation and so on. Therefore, it is necessary to formulate 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
106 
 
a feasible and efficient network security plan according to 
the objective of the all-round network security strategy. We 
should reasonably allocate all kinds of resources and 
coordinate the relations in all aspects. 
The plan mainly includes eight points: 
1) To establish an active defense system. Identify key 
infrastructure and interdependence. The software and 
hardware of the network system, which is the carrier of 
information dissemination, storage and processing in the 
vulnerability information network system, is an important 
infrastructure in the whole system. The interdependence 
between these facilities, especially the key infrastructure, is 
given full attention. It also conducts continuous vulnerability 
assessment and audit of the software and hardware systems 
used in the network. The ability of the invaders to destroy 
the critical infrastructure is estimated. Develop a practical 
scheme to repair the vulnerability of the system and 
constantly modify and update the scheme. 
The evaluation and audit work will effectively destroy 
the invaders' attempt, which is bound to be the target of the 
invaders to carry out the attack. Therefore, enough attention 
should be given to the safety of the assessment and audit 
work itself. 
2) Detection of attacks and illegal intrusion, and pay 
attention to the collection of network security information. 
Acknowledgement and correction of vulnerability can 
delay but not completely prevent malicious intrusion to the 
information network system. Therefore, we need to carry out 
active defense at all levels of information network system, 
install and configure intrusion detection system, vulnerability 
scanning system, emergency response system and so on. The 
network management department should always pay 
attention to the collection of network security information, 
help the end users to resist attacks and prevent virus invasion. 
Establish security management organization according to the 
network operation situation. 
a) Safety management group. The Group monitors and 
manages the entire network system and coordinates the work 
of the group and other groups.  When attacked, the system 
is resumed with the other groups. 
b) Emergency response team. Responsible for security 
technology research and development, providing expert help 
to other groups to help them isolate, control, and resolve 
intrusion and attacks. In the case of attack, it is able to 
respond quickly and provide solutions. 
c) Intrusion detection team. It is responsible for 
uninterrupted network security detection, and to collect 
security information legally, and provide security 
information for other groups at any time. The system backup 
work is done in collaboration with the operation Department 
to support the recovery work after the attack. 
3) Improve fast response and resilience 
Response and recovery plans are formulated in each key 
infrastructure and key information of each category in the 
system. In the case of attack, it can be controlled in time, at 
least to ensure the minimum operation of the network, so that 
the work of other departments is less affected. 
When an attack occurs, the response is as follows: 
a) The rapid control of the intruders and blocking the 
access to the system. 
b) Other more stringent defense measures are quickly 
launched. 
c) Close the non-critical operating system. 
d) To enable the redundant takeover system in an 
emergency, and so on. 
After blocking the invasion, it is necessary to quickly 
restore or rebuild the system that is attacked or infected, and 
should have the corresponding recovery capability for 
different attacks. 
a) Physical recovery, set up spare equipment, and 
dredge the network as soon as possible. 
b) The soft and hardware loopholes in the repair 
system. 
c) Repair or replace damaged soft and hardware 
resources. 
d) Recover the damaged data from the backup database 
as soon as possible. 
e) When the time and technical conditions are allowed, 
the intrusion information is analyzed and the source of 
invasion is traced. If necessary, information is provided to 
the public security organs. 
2018 International Conference on Sensor Network and Computer Engineering (ICSNCE 2018) 
107 
 
4) Prioritization of key facilities and information, and 
level management. 
Prioritize key facilities and information. The more 
sensitive information and the facilities that have a great 
impact on the operation, the more valuable it is. At the same 
time, they are more likely to encounter risks. Therefore, we 
need to take more secure measures for facilities and 
information with high priority, so that intruders can't 
encroach on critical facilities and obtain confidential 
information in a general way. Even if you get it, you can't 
parse the actual meaning of the information. 
5) Pay attention to the collection and exchange of 
information, consistent with national law 
In order to ensure the security of the network, it is 
necessary to establish a reliable, unimpeded and special 
communication channel. Establish a unified safety standard. 
The network management department should work closely 
with other departments to share security information and 
strengthen the research and development of security related 
technologies.  
6) Pay attention to the training and employment of talents 
and strengthen the construction of institutions 
Invite some information security experts to carry out 
continuous safety training for the existing network managers, 
actively hire and educate other personnel to make up for the 
lack of safety talents. 
In addition, we have to establish a team of part-time 
security administrators. 
7) Strengthen the construction of the system and improve 
the management level 
Under the guidance of national law, the current 
regulations and regulations are constantly revised and 
perfected. It provides a legal framework for the security of 
information network, and constantly improves the 
management level. 
8) Strengthen the safety education for all kinds of 
personnel so as to make the public understand the necessity 
of improving the network security. 
Improve the public awareness of network security, 
enhance the threat to the information system and their 
understanding and understanding of their characteristics. 
Improve the ability of our defended invaders to attack before 
the disastrous events come 
III. CONCLUSION 
At present, the problem of network security has become a 
serious form that affects the national security and social 
stability. The implementation of network security plan has 
shown profound practical significance. In the long process of 
security assurance, the network security plan is just the first 
step, but we can be sure that the problem of network security 
will also receive more and more attention. 
 
REFERENCE 
[1] Gu Huaxiang. The legal measures and Enlightenment for the security 
of information security abroad [J]. Reform of administrative 
managemen.2010(12):70-74. 
[2] Ma Minhu. Internet security law[M]. Xi'an Jiao Tong University 
press.2003. 
[3] Zhang Lei. Development of computer information network 
technology [J]. computer knowledge and technology. 2014 
(03):482-484. 
[4] Wei Suming. Discussion on the computer information network 
security technology and security measures [J]. Electronics World. 
2017 (03):20-21.
 
 


The Establishment and Implementation of Information Network Security Plan

Todorov, Plamen

Nestorova, Rodina

Batalov, Anastas

The sonoanatomy of lumbar erector spinae and its iliac attachment – the potential substrate of the iliac crest pain syndrome, an ultrasound study in healthy subjects

Martin, John Levi

The Structure of Node and Edge Generation in a Delusional Social Network*

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