University of Thi-Qar Journal for Engineering Sciences

Dual linear polarized cross-slot patch antenna is a good candidate for modern base station antennas in sub-6
GHz fifth-generation (5G) cellular communications due to its low profile, low cost and moderate bandwidth. The
best-obtained results of the single antenna design demonstrate a wide impedance bandwidth of 19.72% (3.2
3.9 GHz) for VSWR < 1.4, isolation of less than 50 dB between both ports, and a high gain of 10.5 dBi. The
designed dual-polarized antenna was placed in a two-element array that is formed once with and once without
via pins in two cases: 1- vertical/horizontal polarization. 2- ±45° slant polarization. The radiation pattern in both
incidents has been studied and reported. In case one, the results show that the mutual coupling deteriorates
the radiation pattern with the side lobe of around -12.6 dB at 3.4 GHz. However, the sidelobe level is better at
the level of -19 dB, although not acceptable in the case of square vias. The S11 is good from 3.25 GHz to 3.7 GHz
(450 MHz). Similarly, the gain is 13.5 dBi without a via and with a via. A great result: an increase from 10.5 dBi
for a single element to 13.5 dBi for a two-antenna array. In case two, the best result obtained in this scenario is
that the S11 is below –10 dB from 3.2 to 3.9 (700 MHz) without the use of vias. The 45-degree slant radiation
patterns of the antenna, which are plotted in both perpendicular radiations. Both co-polar and cross-polar
patterns are shown and are overlaid. The VSWR is less than 1.5 in all cases. The results obtained and the
compatibility achieved in this direction allow for the possibility of using this antenna in many applications in
modern communications systems, such as advanced antenna systems (AAS) and radars.

This paper is a theory-driven quantitative method in cultural contexts, to produce a novel method for evaluating
the impact of Visual Permeability (VP) and Opacity (VO) with a focus on social norms of privacy on privacy in the
urban neighborhood fabric. A mathematical model based on the Sigmoid function is developed to quantify
privacy (P) by integrating key variables: VP /VO, Shared Visual Area (????????), and a privacy coefficient (k). The
proposed mathematical model based on the Sigmoid function. Across seven neighborhood plans, a non-linear
model based on the Sigmoid function was employed across seven neighborhood plans to evaluate the privacy
levels by analyzing the surface area of the VP, VO areas, and ???????? network influencing the residential blocks within
each neighborhood fabrics. To achieve this, the length and width of each block in the studied neighborhoods
were calculated to determine the shaded areas of VP, VO, and ???????? . However, the height as a third dimension was
disregarded, since it lies beyond the scope of this study. The obtained results indicated statistically significant
privacy outcomes (p<0.01), revealing that privacy levels increase asymptotically with the expansion of VP and
VO gaps, since this threshold effects in shared space interactions across the model coefficient sensitivity around
k ≈ 2.99. This work advances a quantifiable framework for privacy levels in the urban fabrics, though future
studies should integrate dynamic factors, and perceptual validation for optimizing privacy-connectivity balances
in neighborhood design.

The current study aims to address the environmental challenge of nutrient enrichment in freshwater ecosystems,
particularly in the Tigris River, by providing a comprehensive assessment of nutrient concentrations, including
sulfates (SO₄²⁻), nitrites (NO₂⁻), nitrates (NO₃⁻), ammonium (NH₄⁺), and phosphates (PO₄³⁻), evaluating the
temporal and spatial distribution, and identifying the most important human -based activities contributing to
the load of nutrient. Samples were collected from six sites distributed along the river within Baghdad city, over
three years (2020–2022). The results showed a clear spatial variation, with concentrations of most nutrients
gradually rising towards southern sites, indicating the impact of accumulated human activities such as sewage,
industrial discharges, and agricultural runoff. Nitrates and phosphates were highest at sites near dense urban
and industrial areas, while nitrite concentrations were generally low but appeared to be an indicator of
incomplete biological activity. Sulfate concentrations (211–233 mg/L) exceed the environmental limits allowed
under the 1967 Iraqi River Maintenance Regulation, and show a need for better water management and regular
monitoring. In terms of time, the data showed significant annual changes in nutrient concentrations, with an
increase in sulfate and phosphate concentrations recorded in 2022 and 2021, respectively, compared to
previous years, which may reflect an increase in untreated discharges or the effects of drought and reduced
river flow. In contrast, nitrate concentrations declined sharply in 2021 and rose again in 2022. Nitrite and
ammonia concentrations remained relatively stable over the three years. The research recommends the need
to strengthen continuous environmental monitoring systems, update national laws to include nutrient
pollutants such as nitrite, and enhance the efficiency of water treatment plants, with the aim of reducing
eutrophication and protecting the river ecosystem.