IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-11 DOI: 10.1016/j.ijleo.2025.172639

Indira Sundaram , J. Sivapragasam , Sathishkumar Perumal

This study presents a numerical investigation of electromagnetic (EM) soliton propagation and collision phenomena in an anisotropic ferromagnetic medium characterized by higher-order nonlinearity and dispersion. The interaction between the magnetization of the medium and the magnetic field component of the EM wave is studied by solving Maxwell’s equations coupled with the Landau-Lifshitz (L-L) equation, which governs the magnetization dynamics. The resulting nonlinear magnetization behavior is described by a generalized derivative nonlinear Schrödinger (DNLS) equation, selected for its ability to capture complex spin interactions and electromagnetically induced nonlinear effects that are inadequately represented in conventional integrable models. To investigate the nonlinear spin excitations, we perform numerical simulations by solving the generalized DNLS equation using the Method of Lines, implemented in Mathematica software. This approach enables the identification of nonlinear spin excitations in the form of damped and amplitude-modulated one-soliton structures and phase-sensitive two-soliton collisions. Despite energy dissipation, the interactions retain spatial coherence, demonstrating the robustness of solitonic behavior under dispersive and nonlinear perturbations. Dispersion plays a critical role in modulating collision timing and shaping the post-interaction profiles. These findings advance the understanding of soliton robustness under perturbative conditions and provide valuable insights into nonlinear EM wave propagation with potential applications in magneto-optic switching and soliton-based waveguide technologies.

本文对具有高阶非线性和色散的各向异性铁磁介质中电磁孤子的传播和碰撞现象进行了数值研究。通过求解麦克斯韦方程组和控制磁化动力学的Landau-Lifshitz （L-L）方程，研究了介质磁化强度与电磁波磁场分量的相互作用。由此产生的非线性磁化行为由广义导数非线性Schrödinger （DNLS）方程描述，选择该方程是因为它能够捕获复杂的自旋相互作用和电磁感应非线性效应，这些效应在传统的可积模型中无法充分表示。为了研究非线性自旋激励，我们使用Mathematica软件实现的线法（Method of Lines）对广义DNLS方程进行了数值模拟。这种方法能够识别非线性自旋激励的阻尼和振幅调制的单孤子结构和相敏双孤子碰撞的形式。尽管能量耗散，相互作用仍然保持空间相干性，证明了在色散和非线性扰动下孤子行为的鲁棒性。色散在调制碰撞时间和形成相互作用后的轮廓中起着关键作用。这些发现促进了对微扰条件下孤子鲁棒性的理解，并为非线性电磁波传播提供了有价值的见解，具有在磁光开关和基于孤子的波导技术中的潜在应用。

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引用次数: 0

Propagation of vector solitons in waveguides with Helmholtz resonators: Transmission-line approach 亥姆霍兹谐振器波导中矢量孤子的传播：在线传输方法

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-09 DOI: 10.1016/j.ijleo.2025.172635

Souleymanou Abbagari , Alphonse Houwe , Lanre Akinyemi , Doka Yamigno Serge , Bouetou Thomas Bouetou

This paper investigates vector soliton interactions within an air-filled acoustic waveguide that is side-loaded with Helmholtz resonators and modeled as a transmission line incorporating nearest-neighbor coupling. Using a semi-discrete approximation, we derive coupled nonlinear Schrödinger equations that reveal how self-phase and cross-phase modulation depend on the normalized frequency. Analytical results indicate that only coupled bright-bright and dark-dark soliton interactions can propagate within the frequency bands supported by the resonator structure, while bright-dark and dark-bright soliton pairs are inhibited due to the influence of coupling strength. Modulation instability analysis highlights the role of nearest-neighbor coupling in altering the intensity and bandwidth of these solitons. Numerical simulations further demonstrate that the waveguide configuration supports the long-term evolution of wavenumbers, giving rise to rogue waves and periodic breathers under varying coupling conditions. Notably, the excitation of specific frequency bands allows for the emergence of Akhmediev breathers of types A and B during certain propagation intervals. In general, this study unveils novel wave dynamics introduced by incorporating nearest-neighbor coupling in acoustic waveguides with Helmholtz resonators.

本文研究了侧面加载亥姆霍兹谐振器的充气声波导中的矢量孤子相互作用，并将其建模为包含最近邻耦合的传输线。使用半离散近似，我们推导出耦合非线性Schrödinger方程，揭示了自相位和交叉相位调制如何依赖于归一化频率。分析结果表明，只有耦合的亮-亮和暗-暗孤子相互作用才能在谐振腔结构支持的频带内传播，而由于耦合强度的影响，亮-暗和暗-亮孤子对被抑制。调制不稳定性分析强调了最近邻耦合在改变这些孤子的强度和带宽中的作用。数值模拟进一步表明，波导结构支持波数的长期演变，在不同的耦合条件下产生异常波和周期性呼吸。值得注意的是，特定频段的激发允许在特定传播间隔内出现A型和B型艾哈迈耶夫呼吸器。总的来说，这项研究揭示了通过将声波波导中最近邻耦合与亥姆霍兹谐振器相结合而引入的新的波动动力学。

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引用次数: 0

Ultra-broadband three-octave supercontinuum generation in a dispersion-engineered chalcogenide inverse rib waveguide 色散工程硫族逆肋波导中超宽带三倍频超连续谱的产生

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-08 DOI: 10.1016/j.ijleo.2025.172638

Kamiul Islam , Joyonta Das Joy , Md.Shakibur Rahman , Md.Ismail Hossain , Nayem Al Kayed , Rakayet Rafi , M.R. Karim , Jobaida Akhtar , Mohammad Istiaque Reja

This paper presents a novel dispersion-engineered inverse rib waveguide design for ultra-broadband supercontinuum generation (SCG), utilizing an

{As}_{2} {Se}_{3}

chalcogenide glass core with

GeAsS / {MgF}_{2}

cladding layers. The proposed structure achieves dispersion flattening over a wide range, enhancing nonlinear interactions for efficient spectral broadening under a 3.6

μ

m pump laser. Optimized waveguide geometry and material composition yield an output spectrum spanning 1.99–16.58

μ

m (3.06 octaves) at 4 kW peak pump power. Even at a reduced pump power of 2 kW, the supercontinuum extends from 4

μ

m to 16

μ

m, covering nearly two octaves, showcasing superior spectral broadening at lower power compared to other designs. The design maintains power stability and near-zero dispersion, which are essential for coherent SCG. The broad spectral range and low-power efficiency make the waveguide suitable for environmental monitoring, gas sensing, chemical analysis, biomedical imaging, and thermal imaging. Integration of

{MgF}_{2}

cladding enhances mechanical durability and stability.

本文提出了一种新型的色散工程逆肋波导设计，用于超宽带超连续介质产生（SCG），利用As2Se3硫系玻璃芯和GeAsS/MgF2包层。该结构在宽范围内实现了色散平坦化，增强了非线性相互作用，在3.6 μm泵浦激光器下实现了有效的光谱展宽。优化的波导几何形状和材料组成在4 kW峰值泵浦功率下产生1.99-16.58 μm（3.06倍频）的输出频谱。即使在泵浦功率降低至2 kW时，超连续谱也可以从4 μm扩展到16 μm，覆盖近两个八度程，与其他设计相比，在较低功率下表现出优异的光谱展宽。该设计保持了功率稳定性和近零色散，这对于相干SCG至关重要。宽光谱范围和低功耗效率使波导适用于环境监测，气体传感，化学分析，生物医学成像和热成像。MgF2包层的集成提高了机械耐久性和稳定性。

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引用次数: 0

Electronic, transport and optical properties of a p-type transparent conductive oxides family A2B2O7 (A=Sn, Pb, B= Nb, Ta): A density functional theory study p型透明导电氧化物家族A2B2O7 （a =Sn, Pb， B= Nb, Ta）的电子、输运和光学性质：密度泛函理论研究

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-05 DOI: 10.1016/j.ijleo.2025.172634

Ting Yang , Wen-Guang Li , Zheng-Tang Liu , Qi-Jun Liu

Transparent conductive oxides (TCOs) are indispensable for next-generation optoelectronics, yet high-performance p-type TCOs remain scarce. In this theoretical study, we present a systematic density-functional-theory investigation of the cubic pyrochlore-structured oxides A₂B₂O₇ (A = Sn, Pb; B = Nb, Ta). All four compounds are predicted to be mechanically stable indirect-gap semiconductors. Using the ionization-energy-difference criterion combined with hybrid-HSE06 calculations, we identify Sn₂Nb₂O₇, Sn₂Ta₂O₇ and Pb₂Ta₂O₇ as promising intrinsic p-type conductors, with Sn₂Nb₂O₇ exhibiting the highest theoretical hole mobility (10.5 cm² V⁻¹ s⁻¹) and Sn₂Ta₂O₇ showing the lowest visible-light absorption. Our computational results provide quantitative design rules for pyrochlore-based p-type TCOs and point toward experimentally verifiable candidates for transparent electronics.

透明导电氧化物（tco）是下一代光电子技术不可或缺的材料，但高性能p型tco仍然稀缺。在这一理论研究中，我们提出了一个系统的密度泛函理论研究立方火石结构氧化物a₂B₂O₇（a = Sn, Pb; B = Nb, Ta）。预计这四种化合物都是机械稳定的间接间隙半导体。利用电离能差标准结合hybrid-HSE06计算，我们确定Sn₂Nb₂O₇、Sn₂Ta₂O₇和Pb₂Ta₂O₇是有潜力的本态p型导体，其中Sn₂Nb₂O₇的理论空穴迁移率最高（10.5 cm²V⁻¹s⁻¹），Sn₂Ta₂O₇的可见光吸收率最低。我们的计算结果为基于焦绿石的p型tco提供了定量设计规则，并指出了实验可验证的透明电子候选材料。

引用次数: 0

Advancements in terahertz metamaterial absorber sensor design: Dielectric-etched hexagonal architectures for enhanced biochemical sensing 太赫兹超材料吸收传感器设计的进展：用于增强生化传感的介电蚀刻六边形结构

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-05 DOI: 10.1016/j.ijleo.2025.172637

Patharakorn Rattanawan, Asmar Sathukarn, Nutthamon Limsuwan, Khwanchai Tantiwanichapan

This study presents a terahertz (THz) metal–insulator–metal (MIM) metamaterial absorber designed for high-sensitivity biochemical sensing through two sequential design mechanisms. The first mechanism establishes a periodic hexagonal resonant structure—consisting of a solid hexagon and a hexagonal shape formed by rectangular metal bars—that creates a hexagonal-edge unit cell capable of strong field confinement and enhanced sensitivity compared with conventional geometries. Building on this primary structure, the second mechanism introduces a targeted etching process applied to the dielectric layer. Straight and sloped etching profiles are used to progressively expose the resonant surfaces, thereby increasing the direct interaction between the electromagnetic fields and the surrounding analyte. With this combined structural and processing approach, the hexagonal bar pattern achieves ultra-high sensitivity, increasing from 72 to 378 GHz/RIU at a straight dielectric-layer etch depth of 2.0 µm, corresponding to a figure of merit (FOM) of 11.8 RIU⁻¹ and a quality factor (Q-factor) of 86. These results demonstrate that integrating a hexagonal-edge resonant structure with a controlled dielectric etching process offers an effective route to achieving ultra-high sensitivity in THz metamaterial absorbers for diverse sensing applications.

本研究提出一种太赫兹（THz）金属-绝缘体-金属（MIM）超材料吸收器，通过两种顺序设计机制设计用于高灵敏度生化传感。第一种机制建立了一个周期性六边形共振结构——由一个实心六边形和一个由矩形金属棒构成的六边形组成——这创造了一个六边形边缘单元，与传统几何结构相比，它具有强场约束和增强灵敏度的能力。在这个主要结构的基础上，第二种机制引入了一种应用于介电层的定向蚀刻工艺。直线和倾斜的蚀刻剖面用于逐渐暴露谐振表面，从而增加电磁场与周围分析物之间的直接相互作用。采用这种结构和加工相结合的方法，六边形棒形图案实现了超高的灵敏度，在直介电层蚀刻深度2.0 µm时，从72增加到378 GHz/RIU，相应的优点系数（FOM）为11.8 RIU⁻¹ ，质量因子（q因子）为86。这些结果表明，将六边形边缘谐振结构与受控介质蚀刻工艺相结合，为实现超高灵敏度的太赫兹超材料吸收器提供了有效途径，可用于各种传感应用。

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引用次数: 0

Refined thermal-induced grafting of acrylamide onto polypropylene fibers: Optimization, optical characterization, and antimicrobial enhancement 丙烯酰胺在聚丙烯纤维上的精细热诱导接枝：优化、光学表征和抗菌增强

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-04 DOI: 10.1016/j.ijleo.2025.172636

G.M. Abo-Lila , T.Z.N. Sokkar , E.A. Seisa , E.Z. Omar , M.M. Metwally

This study presents a promising approach to synthesizing antimicrobial polypropylene fibers (PP) through thermal-induced grafting of acrylamide (AM) using Fenton's reagent as an initiator. The research achieved a breakthrough grafting percentage of 32 % under relatively mild conditions (80°C), marking a significant improvement over previous methods which typically yielded 3–27 % grafting. Through systematic optimization of reaction parameters (0.85 mol/L AM, 0.03 mol/L Fe (II), 4.26 mol/L H₂O₂, and 1.5 g/L PP fiber), the study established optimal conditions for efficient grafting. Notably, the research introduced an advanced application of the Mach-Zehnder interferometer technique to characterize the optical and structural properties of modified fibers, providing unprecedented insights into the relationship between grafting concentration and molecular organization. The modified fibers demonstrated significant antimicrobial activity against both gram-positive and gram-negative bacteria, as well as fungi. Comprehensive characterization using FT-IR, SEM, and XRD revealed that PP-g-AM (0.85 mol/L) exhibited superior properties, including enhanced crystallinity (CI increase from 38.57 % to 41.27 %) and optimal molecular alignment. This study bridges a critical gap in PP fiber modification technology by combining high grafting efficiency with detailed optical characterization, offering new possibilities for developing advanced antimicrobial textiles with tailored properties.

提出了一种以Fenton试剂为引发剂，通过丙烯酰胺（AM）热诱导接枝合成抗菌聚丙烯纤维（PP）的新方法。该研究在相对温和的条件下（80°C）取得了32 %的突破性接枝率，这标志着比以前的方法有了显著的改进，通常接枝率为3-27 %。通过系统优化反应参数（0.85 mol/L AM、0.03 mol/L Fe （II）、4.26 mol/L H₂O₂、1.5 g/L PP纤维），确定了高效接枝的最佳条件。值得注意的是，该研究引入了Mach-Zehnder干涉仪技术的先进应用，以表征改性纤维的光学和结构特性，为接枝浓度与分子组织之间的关系提供了前所未有的见解。改性纤维对革兰氏阳性和革兰氏阴性细菌以及真菌均表现出显著的抗菌活性。FT-IR、SEM和XRD综合表征表明，PP-g-AM（0.85 mol/L）具有优异的性能，包括结晶度增强（CI从38.57 %增加到41.27 %）和最佳的分子取向。该研究通过将高接枝效率与详细的光学表征相结合，填补了PP纤维改性技术的关键空白，为开发具有定制性能的先进抗菌纺织品提供了新的可能性。

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引用次数: 0

Highly sensitive bullet-shaped fiber-optic Michelson temperature sensing probe based on Vernier effect 基于游标效应的高灵敏度子弹形光纤迈克尔逊温度传感探头

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-02 DOI: 10.1016/j.ijleo.2025.172633

Min Li, Ruixin Ren, Jie Yang, Lingyu Du, Rubing Bai, Aimin Cong, Xiaowei Li

A highly sensitive bullet-shaped fiber-optic Michelson temperature sensing probe with a wide measurement range is proposed in this paper, and it is fabricated using fiber fusion tapering technology and ultraviolet curing technology. First, a section of fiber taper is fused at the center of a multimode fiber (MMF) with a flat-cut end. The length and diameter of the fiber taper are 52 μm and 52 μm, respectively. Then, the fiber taper is completely encapsulated by SU-8 photoresist. The fiber taper and SU-8 photoresist form microcavity 1 and microcavity 2, respectively. The two microcavities are arranged in parallel at the end of the MMF, and a bullet-shaped fiber sensing probe is formed. The optical paths of two microcavities are close. According to the theory of the Vernier effect, a Vernier envelope appears in the interference spectrum of the proposed fiber-optic sensing probe. However, the Vernier envelope is not directly observed in the interference spectrum due to the presence of a microcavity 3. Microcavity 3 is formed by the superposition of microcavity 1 and microcavity 2. The distinct Vernier envelope can be observed by filtering out the interference spectrum of microcavity 3. The shifts of the Vernier envelope and the high-frequency peak with temperature are monitored. The sensitivity of this probe reaches 2.2627 nm/°C within the temperature range of −10 °C to 62 °C. The proposed sensing probe features a ultra-compact structure, a wide temperature measurement range and high sensitivity, making it a promising breakthrough in the field of temperature monitoring.

本文提出了一种高灵敏度、宽测量范围的子弹形光纤迈克尔逊温度传感探头，该探头采用光纤熔锥技术和紫外固化技术制备。首先，在多模光纤（MMF）的中心熔接一段光纤锥度，一端是平切的。光纤锥度长度为52 μm，直径为52 μm。然后，用SU-8光刻胶完全封装光纤锥度。光纤锥度和SU-8光刻胶分别形成微腔1和微腔2。在MMF末端平行布置两个微腔，形成子弹状光纤传感探头。两个微腔的光路很接近。根据游标效应理论，在光纤传感探头的干涉谱中出现游标包络。然而，由于微腔的存在，在干涉光谱中不能直接观察到游标包络。微腔3是由微腔1和微腔2叠加而成。通过滤除微腔3的干扰谱，可以观察到明显的游标包络。监测了游标包络线和高频峰值随温度的变化。在−10℃~ 62℃的温度范围内，探头的灵敏度达到2.2627 nm/°C。该传感探头具有结构超紧凑、测温范围宽、灵敏度高的特点，有望成为温度监测领域的突破口。

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引用次数: 0

Design of a flexible, highly isolated multiband f-meta MIMO antenna for 5G sub-6 GHz applications using the theory of characteristic modes 利用特征模式理论设计一种灵活、高度隔离的多频段f-meta MIMO天线，用于5G sub- 6ghz应用

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-12-01 DOI: 10.1016/j.ijleo.2025.172632

Geetanjali Singla , Rashbha Sharma , Rajesh Khanna , Ashish Kumar , A. J.A. Al-Gburi

This paper presents a wideband dual-element flexible metasurface MIMO antenna (f-meta MIMO antenna), using TCM (Theory of Characteristic Modes) optimized metasurface of double-negative (DNG) metamaterial unit cells placed within a slotted rectangular patch. It resonates over a wide bandwidth of 2700 MHz (3.3–6.0 GHz) covering multiple sub-6 GHz bands. It is an extended design of single element flexible metasurface antenna designed on a 0.4 mm flexible sheet of FR-4 substrate achieving a bandwidth of 1000 MHz (3.1–4.1 GHz) in the sub-6 GHz range. A key novelty of this work is that the f-meta MIMO antenna elements maintain a high isolation (S12 > 19 dB) at a very small inter-element gap of 0.003 λ (λ corresponding to 3.35 GHz), without employing any additional isolation enhancement techniques. Furthermore, the f-meta MIMO demonstrates excellent diversity performance, including a low envelope correlation coefficient (< 0.05), high diversity gain (≈ 10 dB), high efficiency (> 85 %), a mean effective gain < −3 dB, and a total active reflection coefficient < −10 dB across the operating bandwidth. In addition, under several bending scenarios, the antenna maintains its compact volume (700 mm³) and preserves multiband operation with high isolation (S12 > 15 dB). This makes the antenna suitable for various 5 GHz applications such as 5 G NR, Wi-Fi and conformal applications such as V2X/ UAV terminals, wearable/ IoT devices.

本文提出了一种宽带双元柔性超表面MIMO天线（f-meta MIMO天线），该天线采用TCM （Theory of Characteristic Modes）优化的双负（DNG）超材料单元格的超表面，放置在开槽矩形贴片内。它在2700 MHz（3.3-6.0 GHz）的宽带宽上谐振，覆盖多个低于6 GHz的频段。它是单元件柔性超表面天线的扩展设计，设计在0.4 mm的FR-4衬底柔性片上，在sub-6 GHz范围内实现了1000 MHz（3.1-4.1 GHz）的带宽。这项工作的一个关键新颖之处在于，f-meta MIMO天线元件在0.003 λ （λ对应3.35 GHz）的非常小的元件间间隙处保持高隔离（S12 > 19 dB），而无需采用任何额外的隔离增强技术。此外，f-meta MIMO具有优异的分集性能，包括低包络相关系数（< 0.05）、高分集增益（≈10 dB）、高效率（> 85 %）、平均有效增益<； −3 dB和总主动反射系数<； −10 dB。此外，在几种弯曲情况下，天线保持其紧凑的体积（700 mm³），并保持高隔离的多频段运行（S12 > 15 dB）。这使得该天线适用于5 G NR、Wi-Fi等各种5 GHz应用以及V2X/无人机终端、可穿戴/物联网设备等保形应用。

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引用次数: 0

Optical modeling and design of Fabry–Perot interferometer sensors for detection of human skin cancer cells 用于人体皮肤癌细胞检测的法布里-珀罗干涉仪传感器光学建模与设计

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-11-27 DOI: 10.1016/j.ijleo.2025.172622

Milan S. Kovačević , Vladimir Marković , Daniele Tosi , Wilfried Blanc , Ivona Kovačević , Ljubica Kuzmanović

This study presents a method for detecting cancer cells in human skin using a fiber-based sensor, referred to as a semi-distributed Fabry–Pérot interferometer (SDI FP sensor). The sensor employs a multimirror Fabry–Pérot structure formed between a single-mode cleaved fiber tip and a high-scattering fiber, whose core is doped with magnesium silicate nanoparticles, placed in contact with the three principal skin layers: epidermis, dermis, and hypodermis. For the first time, human skin is represented as a four-mirror Fabry–Pérot interferometer, with epidermal refractive index and thickness varying in the presence of cancer cells. First, the reflected spectrum of healthy skin tissue is modeled in the infrared wavelength range. Next, alterations in the reflected spectrum are analyzed in the presence of cancer cells, considering their distribution within each skin layer individually. The results reveal distinct shifts in spectral peaks and valleys between healthy and cancerous tissues, demonstrating the potential of the proposed approach for noninvasive detection of cancer cells across different skin layers. Additionally, a more sophisticated model was considered in which the epidermal refractive index varies randomly due to the presence of cancer cells, reflecting the realistic nonuniform distribution of cancer cells within the epidermal tissue. The proposed model provides a solid theoretical foundation for subsequent experimental validation

本研究提出了一种利用光纤传感器检测人体皮肤癌细胞的方法，该传感器被称为半分布式法布里-帕氏干涉仪（SDI FP传感器）。该传感器采用在单模切割纤维尖端和高散射纤维之间形成的多镜法布里-帕姆罗结构，其核心掺杂了硅酸镁纳米颗粒，与皮肤的三个主要层：表皮、真皮层和皮下皮层接触。第一次，人类皮肤被表示为一个四镜法布里-帕姆罗干涉仪，表皮折射率和厚度随着癌细胞的存在而变化。首先，在红外波长范围内对健康皮肤组织的反射光谱进行建模。接下来，在癌细胞存在的情况下分析反射光谱的变化，分别考虑它们在每层皮肤中的分布。结果揭示了健康组织和癌变组织之间光谱峰谷的明显变化，证明了所提出的方法在不同皮肤层中无创检测癌细胞的潜力。此外，我们还考虑了一个更复杂的模型，其中表皮折射率因癌细胞的存在而随机变化，反映了癌细胞在表皮组织内的真实不均匀分布。该模型为后续的实验验证提供了坚实的理论基础

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引用次数: 0

Heap Optimization Based Multi LSTM for enhancing maternal and fetal health monitoring through wearable devices 基于堆优化的多LSTM通过可穿戴设备增强母婴健康监测

IF 3.1 3区物理与天体物理 Q2 Engineering

Optik

Pub Date : 2025-11-26 DOI: 10.1016/j.ijleo.2025.172621

Rajkumar Ettiyan , V. Geetha

Monitoring maternal and fetal health is crucial due to risk such as gestational diabetes, hypertensive disorders, and fetal growth restrictions. Risk prediction with machine learning models and constant monitoring of vital signs using wearable devices is quite challenging. Because these model accuracy depends heavily on high quality unbiased data and lack of sufficient data can lead to unreliable results. To overcome these difficulties, Heap Optimization Based Multi LSTM was created to assess pregnancy risk and monitor fetal health. Initially, wearable sensors are implanted in the mother's body, transmitting necessary data to a mobile application. The Message Queuing Telemetry Transport protocol, is used for transmitting the data to cloud storage system for storing and predicting the health status of pregnant women and fetal. The collected data is pre-processed within cloud system using MIDA-based missing value imputation to ensure data integrity and slice adaptive normalization. The features are selected using Locally Linear Embedding to emphasize relevant aspects, followed by classification HO-MLSTM, which divides fetal health into three stages: normal, questionable, and pathological, and assigns pregnancy risk levels as low, medium, or high. The proposed method achieves 97.4 % fetal health and 94.5 % for maternal risk highlighting the effectiveness of the HO-MLSTM approach in minimizing maternal risk and enhancing fetal health. Consequently, these methods are highly suitable for wearable devices designed to accurately classify pregnancy risk levels and fetal health stages in pregnant women.

由于妊娠期糖尿病、高血压疾病和胎儿生长受限等风险，监测孕产妇和胎儿健康至关重要。使用机器学习模型进行风险预测和使用可穿戴设备持续监测生命体征是相当具有挑战性的。因为这些模型的准确性在很大程度上依赖于高质量的无偏数据，缺乏足够的数据会导致不可靠的结果。为了克服这些困难，建立了基于堆优化的多LSTM来评估妊娠风险和监测胎儿健康。最初，可穿戴传感器被植入母亲体内，将必要的数据传输到移动应用程序。消息队列遥测传输协议，用于将数据传输到云存储系统，用于存储和预测孕妇和胎儿的健康状况。采集到的数据在云系统内使用基于mida的缺失值插值进行预处理，保证数据的完整性和切片自适应归一化。使用局部线性嵌入来选择特征以强调相关方面，然后进行HO-MLSTM分类，将胎儿健康分为正常、可疑和病理三个阶段，并将妊娠风险等级划分为低、中、高。所提出的方法达到97.4% %的胎儿健康和94.5% %的孕产妇风险，突出了HO-MLSTM方法在最大限度地降低孕产妇风险和提高胎儿健康方面的有效性。因此，这些方法非常适用于设计用于准确分类孕妇妊娠风险水平和胎儿健康阶段的可穿戴设备。

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引用次数: 0

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