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Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of anti-cancer drugs. The main symptoms often include sensory disturbances and neuropathic pain, and currently there is no effective treatment for this condition. This study aimed to investigate the suppressive effects of magnolin, an extracellular signal-regulated kinase (ERK) inhibitor substance derived from a 95% EtOH extract of the seeds of Magnolia denudata, on the symptoms of CIPN. A taxol-based anti-cancer drug paclitaxel (PTX) was repeatedly injected (2 mg/kg/day, total 8 mg/kg) into mice to induce CIPN. A neuropathic pain symptom was assessed using a cold allodynia test that scores behaviors of licking and shaking paw after plantar administration of acetone drop. Magnolin was administered intraperitoneally (0.1, 1, or 10 mg/kg) and behavioral changes to acetone drop were measured. The effect of magnolin administration on ERK expression in the dorsal root ganglion (DRG) was investigated using western blot analysis. The results showed that the repeated injections of PTX induced cold allodynia in mice. Magnolin administration exerted an analgesic effect on the PTX-induced cold allodynia and inhibited the ERK phosphorylation in the DRG. These results suggest that magnolin could be developed as an alternative treatment to suppress paclitaxel-induced neuropathic pain symptoms.

This article argues that a stage in history has come where advanced technology, especially that of genetically engineered foods and animals, is quickening the humankind’s downfall. Bacigalupi represents this well in The Windup Girl, a futuristic novel that looks with great focus at the transformation of food and animals in the twenty-third century. In our own world, climate change is creating urgent food issues. Genetically Modified Organism (GMO) technologies, having been initially introduced to overcome dire food shortages, have turned out to have many negative side effects, both in our own world and in the fictional world of The Windup Girl. More problematic are the unknown dangers of food transformation technologies. These technologies are driven by multinational corporations both in the real and fictional worlds, and Bacigalupi suggests that the current trajectories of our food transformation industries and their technologies could lead to the demise of human civilization.

Although the red pepper and its seeds have been studied for metabolic diseases, the effects and potential mechanisms of red pepper seed extract (RPS) on hepatic lipid accumulation are not yet completely understood. This study aimed to evaluate the inhibitory effect of RPS on hepatic lipid accumulation via autophagy. C57BL/6 mice were fed a high-fat diet (HFD) or a HFD supplemented with RPS. RPS treatment inhibited hepatic lipid accumulation by suppressing lipogenesis, inducing hepatic autophagic flux, and activating AMPK in HFD-fed mice. To investigate the effect of RPS on an oleic acid (OA)-induced hepatic steatosis cell model, HepG2 cells were incubated in a high-glucose medium and OA, followed by RPS treatment. RPS treatment decreased OA-induced lipid accumulation and reduced the expression of lipogenesis-associated proteins. Autophagic flux dramatically increased in the RPS-treated group. RPS phosphorylated AMPK in a dose-dependent manner, thereby dephosphorylated mTOR. Autophagy inhibition with 3-methyladenine (3-MA) antagonized RPS-induced suppression of lipogenesis-related protein expressions. Moreover, the knockdown of endogenous AMPK also antagonized the RPS-induced regulation of lipid accumulation and autophagy. Our findings provide new insights into the beneficial effects of RPS on hepatic lipid accumulation through the AMPK-dependent autophagy-mediated downregulation of lipogenesis.

Background Multiple sclerosis (MS) and its animal model, the experimental autoimmune encephalomyelitis (EAE), are primarily characterized as dysfunction of the blood-brain barrier (BBB). Ginsenoside-Rg3-enriched Korean red ginseng extract (Rg3-KRGE) is known to exert neuroprotective, anti-inflammatory, and anti-oxidative effects on neurological disorders. However, effects of Rg3-KRGE in EAE remain unclear. Methods Here, we investigated whether Rg3-KRGE may improve the symptoms and pathological features of myelin oligodendroglial glycoprotein (MOG)35-55 peptide – induced chronic EAE mice through improving the integrity of the BBB. Results Rg3-KRGE decreased EAE score and spinal demyelination. Rg3-KRGE inhibited Evan's blue dye leakage in spinal cord, suppressed increases of adhesion molecule platelet endothelial cell adhesion molecule-1, extracellular matrix proteins fibronection, and matrix metallopeptidase-9, and prevented decreases of tight junction proteins zonula occludens-1, claudin-3, and claudin-5 in spinal cord following EAE induction. Rg3-KRGE repressed increases of proinflammatory transcripts cyclooxygenase-2, inducible nitric oxide synthase, interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha, but enhanced expression levels of anti-inflammatory transcripts arginase-1 and IL-10 in the spinal cord following EAE induction. Rg3-KRGE inhibited the expression of oxidative stress markers (MitoSOX and 4-hydroxynonenal), the enhancement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and NOX4, and NADPH activity in the spinal cord of chronic EAE mice. Furthermore, apocynin, a NOX inhibitor, mimicked beneficial effects of Rg3-KRGE in chronic EAE mice. Conclusion Our findings suggest that Rg3-KRGE might alleviate behavioral symptoms and pathological features of MS by improving BBB integrity through modulation of NOX2/4 expression.

The polymer electrolyte membrane fuel cell has been widely studied in many fields and is being commercialized through various applications such as automobiles or distributed power generation. However, there are some fuel-cell operation stability and durability issues yet to be solved. One such problem is how to monitor the hydration condition within a fuel cell quickly and precisely for fault detection during operation. This study presents a method for monitoring the water management status in the fuel cell on-line. The relationship between equivalent circuit elements, voltage and current is described mathematically, and based on this equation, the equivalent circuit elements are estimated on-line through the voltage and current values measured in the experiment. The experiment is performed in three pre-defined states: normal, dry-out, and flooding. The parameter values of the equivalent circuit estimated by the least square method show different behaviors for each state, and it is confirmed that it is possible to implement fault isolation related to water management of a polymer electrolyte membrane fuel cell through parameter estimation, showing different behaviors in each state.

Coronavirus disease 2019 (COVID-19) is currently a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 are directly associated with hyper-activation of innate immune response that excessively produce pro-inflammatory cytokines and induce cytokine storm, leading to multi-organ-failure and significant morbidity/mortality. Currently, several antiviral drugs such as Paxlovid (nirmatrelvir and ritonavir) and molnupiravir are authorized to treat mild to moderate COVID-19, however, there are still no drugs that can specifically fight against challenges of SARS-CoV-2 variants.

The recoil force that causes the rearward movement of the gun is generated during firing a railgun as a conventional gun. According to Newton’s third law, it should be equal to the electromagnetic force that accelerates an armature. It continues to act as long as current flows in the rails even when the muzzle arc occurs immediately after the armature exits. The recoil force in a railgun increases being proportional to the square of current as current increases. A recoil system should be installed to absorb the recoil force when it is so large that a carriage cannot withstand the load transmitted directly to it. Design and experiment of the recoil system using friction springs for a railgun are described in this paper. The space and volume to place a spring type of recoil system into the carriage are required relatively small to a hydraulic type and it has a simple structure. The recoil velocity of the railgun can be rapidly down due to the excellent damping characteristics of friction springs during two or three cyclic motions after firing. The load imposed to the carriage can be reduced to over one-tenth of the recoil force with 15 mm of recoil length when about 1560 N · s of firing impulse is applied.

A resistive overlay rail for an electromagnetic launcher was tested and its inductance gradients were analyzed using 2-D and 3-D finite-element methods (FEMs). The overlay rail was consisted with outside copper rail for good conduction of current and inside steel one for the prevention of rail wear. When the armature slides along the steel rail, electrical current flows mainly through the copper rail before it reaches the armature tail and it penetrates the steel rail at the armature tail due to the velocity skin effect. The rail inductance gradient $L^{\prime }_{R}$ is obtained with 2-D FEM in both frequency and time domains without an armature and the propulsive inductance gradient $L^{\prime }_{P}$ are obtained with 3-D transient FEM with a moving armature. A C-shaped aluminum armature was launched with the velocity over 2 km/s on the resistive overlay rail and gouging was not induced, while it appeared in the experiment with a copper rail. Using the two obtained inductance gradients, the circuit simulation was conducted and it explains the experiment result with a good agreement.

This paper proposes a real time monitoring method of the status of flooding and drying out of a proton exchange membrane in a Polymer Electrolyte Membrane Fuel Cell (PEMFC). The PEMFC stack is modeled using the simplified Randle’s equivalent electrical circuit. The measured stack voltages after a step current consumption provides the criterion for the water balance condition in the PEMFC. The voltage response has different characteristics in drying out and flooding conditions and it is possible to find membrane resistance and activation resistance corresponding to the equivalent circuit model. Since these resistance elements show a different behavior in each of the water balance states, it is possible to judge the water balance condition in the PEMFC. Furthermore, this method requires no additional costly equipment and needs only simple signal processing. The proposed method is applied to a PEMFC stack operating in normal, drying, and flooding conditions, with the results verifying that the new method can monitor the water contents of the stack.

The rational regulation of programmed cell death by means of autophagy and apoptosis has been considered a potential treatment strategy for cancer. We demonstrated the inhibitory effect of St. John&rsquo, s Wort (SJW) on growth in the triple-negative breast cancer (TNBC) cell line and xenografted mice and its target mechanism concerning autophagic and apoptotic cell death. SJW ethanol extract (SJWE) inhibited proliferation in a dose-dependent manner. SJWE treatment dramatically increased autophagy flux and apoptosis compared with the control. The autophagy inhibitor, 3-methyladenine (3-MA), reversed the SJWE-induced inhibition of cell proliferation and regulation of autophagy and apoptosis, indicating that SJWE induced apoptosis through prodeath autophagy. Furthermore, SJWE inhibited tumor growth and induced autophagy and apoptosis in the tumor of MDA-MB-231 xenografted athymic nude mice. Our results indicate that SJWE might have great potential as a new anticancer therapy for triple-negative breast cancer by inducing prodeath autophagy and apoptosis.

Poorly regulated inflammation is believed to be the most predominant factor that can result in a wide scope of diseases including atopic dermatitis (AD). Despite many studies on the effect of pear pomace in obesity-related disorders including dysregulated gut microbiota, the protective effect of pear pomace in AD is still unknown. This study aimed to evaluate the effect of pear pomace ethanol extract (PPE) on AD by inhibiting inflammation.In theCompared to the AD control (AD-C) group, IgE levels were dramatically decreased via PPE treatment. PPE significantly reduced scratching behavior, improved skin symptoms, and decreased ear thickness compared to the AD-C group. In addition, PPE inhibited the DNCB-induced expression of inducible nitrite oxide synthase (iNOS), the receptor for advanced glycation end products, extracellular signal-regulated kinase (ERK) 1/2, and NF-κB. PPE inhibited the LPS-induced overproduction of NO and the enhanced expression of iNOS and cyclooxygenase-2. Moreover, the phosphorylation of ERK1/2 and NF-κB in RAW 264.7 cells was suppressed by PPE.These results suggest that PPE could be explored as a therapeutic agent to prevent AD.

A test circuit of a repetitive critical rate of rise of ON-state current ( di / dt ) for a high-power thyristor is designed and implemented. The operating principle of the test circuit specified in the standard IEC-60747-6 is explained in detail. The design example for the circuit to test repetitive di / dt of 300 A/ $\mu \text{s}$ for a thyristor having a mean ON-state current of 2200 A is presented. The value of the charging resistor is chosen by simulations considering the maximum charging current, power consumption of the charging resistor, maximum charging voltage of the capacitor, and the peak pulsed current of the thyristor. The best firing angles of the thyristor are decided based on the simulations focused on the pulsed current of the thyristor, charging diode current, apparent power of the step-up transformer, and reverse voltage of the charging diode. The repetitive di / dt test prototype of 300 A/ $\mu \text{s}$ , 60 Hz, and 60 shots is assembled with the Infineon light-triggered thyristor (T1503N). The design results are verified by an experiment.

We present analyses of the transient inductance gradient of an electromagnetic launcher with the sliding contact between rails and armature. When the armature moves along the rails, electrical current concentrates on the contact trailing edge of the armature due to the velocity skin effect, affecting input current spreading into the rail. This effect also induces the temporal variation of inductance gradient. Using the 2-D finite-element method (FEM), the rail inductance gradient without an armature is calculated and compared with the propulsive inductance gradient with a moving armature calculated by 3-D FEM. Using the 3-D simulation, the influence of the step on the height difference between the rail and the transient moving armature is investigated. The result shows that the average of transient inductance gradients during acceleration is 10% larger than Kerrisk’s inductance gradient. Also, we found that the axial force on the armature is not significantly affected by the velocity of the armature, while the lateral force on it whose direction is outside the rail increases with the velocity. The circuit simulation using both inductance gradients shows good agreement with the measured current and velocity.

A C-shaped armature in an electromagnetic launcher creates the magnetic pressure on the rear surface of the armature. The transverse component of the magnetic pressure plays a main role to maintain the moving contact between the rails and the armature. It is larger than the repulsive pressure acting against the rails far away from the armature. It might cause the dynamic deflection to be amplified along the entire length of the rails, resulting in the magnification of the contact pressure when the elastic waves of the rails pass through the contact surface. In this paper the dynamic system is modeled as a Timoshenko beam on an elastic foundation subjected to an accelerating pressure combined with the repulsive pressure and the transverse component of the magnetic pressure. The spatial and time history of the accelerating pressure as an applied force of the governing equation is calculated using the experimental current and armature position in the launcher. The influence of the magnetic pressure on the rail deflection is described in point of propagation of the elastic waves. The dynamic deflections at different positions on the rail are compared to show that the dynamic behavior of the rail is strongly affected by the moving velocity of the armature.

Finasteride is commonly used for treatment of alopecia. Because finasteride is a cause of gynecomastia, there is concern regarding the continuation of finasteride therapy after mastectomy. No studies have been performed to determine whether finasteride should be continued after mastectomy when gynecomastia occurs in patients taking finasteride for the treatment of alopecia. The researchers studied the effects of finasteride on gynecomastia recurrence after mastectomy in men with gynecomastia taking finasteride for alopecia. The researchers retrospectively evaluated 1,673 patients with gynecomastia who underwent subcutaneous mastectomy with liposuction at Damsoyu Hospital from January 2014 to December 2016. In total, 52 of the patients were taking finasteride for alopecia before surgery and continued to use it in the same manner after mastectomy. Ultrasonography was performed 1 year after mastectomy. The patients’ median age was 26.5 (24.75–30) years. All 52 patients had bilateral gynecomastia. The median duration of finasteride therapy before and after surgery was 12 (5–25.75) and 33 (27.5–40.5) months, respectively. There were no statistically significant differences between the groups with and without the use of finasteride in relation to postoperative complications and recurrence rates. Taking finasteride seems to have little effect on recurrence in patients with alopecia who have undergone surgical treatment of gynecomastia. Surgeons may recommend continuous finasteride therapy in patients with alopecia who wish to take finasteride after mastectomy.

The critical cell voltage drop in a stack can be followed by stack defect. A method of detecting defective cell is the cell voltage monitoring. The other methods are based on the nonlinear frequency response. In this paper, the superposition principle for the diagnosis of PEMFC stack is introduced. If critical cell voltage drops exist, the stack behaves as a nonlinear system. This nonlinearity can explicitly appear in the ohmic overpotential region of a voltage-current curve. To detect the critical cell voltage drop, a stack is excited by two input direct test-currents which have smaller amplitude than an operating stack current and have an equal distance value from the operating current. If the difference between one voltage excited by a test current and the voltage excited by a load current is not equal to the difference between the other voltage response and the voltage excited by the load current, the stack system acts as a nonlinear system. This means that there is a critical cell voltage drop. The deviation from the value zero of the difference reflects the grade of the system nonlinearity. A simulation model for the stack diagnosis is developed based on the SPP, and experimentally validated.

This study evaluates the flexural behavior of reinforced high-strength concrete beams with electric arc furnace (EAF) oxidizing slag aggregates. The main test parameters include the type of aggregates, compressive strength of concrete, and tension reinforcement ratio. A total of eight simply supported beam specimens subjected to four point loads are cast and tested in flexure. Two types of aggregates, natural and EAF oxidizing slag aggregates, are used in this study. The compressive strength of the concrete is designed to have normal- and high-strengths of 24 MPa and 100 MPa, respectively. The tension reinforcement ratios of beam specimens are 0.3 and 0.5 times the balanced reinforcement ratio for flexure. The experimental results indicated that the flexural strength of specimens was not affected by the type of aggregate, whereas the flexural ductility of specimens with EAF oxidizing slag aggregates was superior to that of specimens with natural aggregates, regardless of the compressive strength of concre...

Electromagnetic Induction Launchers (EIL) have been receiving great attention due to their advantages of noncontact between the coils and a projectile. This paper describes the modeling and design of 3-stage EIL to accelerate a copper projectile of 50 kg with 290 mm diameter. Our EIL consists of three independent driving coils and pulsed power modules to generate separate driving currents. To find efficient acceleration conditions, the appropriate shape of the driving coils and the position of the projectile have been calculated by using a finite element analysis (FEA) method. The results showed that the projectile can be accelerated more effectively as the gap between the coils is smaller; a final velocity of 45 m/s was obtained. The acceleration efficiency was estimated to be 23.4% when a total electrical energy of 216 kJ was discharged.

A 4.8-MJ capacitive pulsed-power system (PPS) was designed and fabricated for electromagnetic launcher (EML) experiment. The PPS consists of eight 600-kJ segments, which can be operated independently. In each segment, six 100-kJ capacitor bank modules, a charging power supply, a dump and charge panel, and control circuit were integrated. The capacitor bank modules in the segment are charged at the same voltage up to 10 kV, but the trigger time of each module can be set up differently. The overall PPS system is controlled by a control program, which sets charging voltage and trigger time of each module and monitors the states of system component. All the control signals are transmitted through fiber optic communication. The 48 unit modules are connected in parallel to EML with high-voltage coaxial cables. A current amplitude of more than 1 MA and a pulsewidth of several milliseconds were achieved by the PPS. The PPS has been applied to several tens of firing experiments of EML successfully. The design, fabrication, and the test results of the 4.8-MJ PPS were described in this paper.

Objectives: This study was conducted to better understand the relationship between health effects and exposure to dusts from a briquette fuel complex in Ansim, Daegu, Korea. Methods: The subjects of this study consisted of 2,980 persons over 40 years old who had lived 20 years or more around a briquette fuel complex in Daegu. We conducted a questionnaire survey, and chest radiography was performed. In addition, chest computed tomography(CT) (335 cases) and pulmonary function test(PFT) (658 cases) were done. Pneumoconiosis was diagnosed if one of three radiologists determined(or suspected) pneumoconiosis. We also conducted in-depth interviews for pneumoconiosis cases. We defined the exposed group as subjects residing within a 500 meter radius from the walls of the briquette fuel complex, and the others were defined as the control group. Results: Subjects in the exposed and control groups are respectively 715(24%) and 2,265 cases(76%). Major respiratory symptoms in the exposed group such as sputum, dyspnea, chest tightness and wheezing were significantly higher than in the control group. By chest radiography, 173 cases of pneumoconiosis or suspicious pneumoconiosis were detected. By PFT, 62 cases(29.5%) of chronic obstructive pulmonary disease(COPD) among 210 asymptomatic subjects were detected. Finally, by chest CT we concluded 28 cases to be pneumoconiosis, and eight cases among them proved to be pneumoconiosis by environmental exposure. Conclusions: Through this study, we concluded that health outcomes such as respiratory symptoms, pneumoconiosis, and COPD were caused by continuous exposure to dusts from the briquette fuel complex. Policies to reduce environmental exposure are needed, and cases of environmental disease should be intensively followed up by the government.

An electromagnetic launcher with a 4.8-MJ pulsed power supply has been fabricated, and experimental tests were started. Through the experiments and calculations, the factors influencing the electrical properties and the performance of the launcher have been investigated. The pulse-forming inductors of the power supply and the rails of the launcher are made of massive conductors showing a prominent skin effect for a transient current. The circuit analysis using constant impedance values has a difficulty in the calculation of the correct voltages between the terminals of the conductors. In addition, the frictional force between the rails and the armature should be considered for a better estimation of the armature motion. To obtain the calculated solutions close to the measured ones, the diffusion of the magnetic flux or current was considered, and the history of the armature motion was reflected in the electrical modeling of the rails. These effects were implemented as voltage correction terms in the circuit equations with the help of the electromagnetic responses to a step-function current. In the equation of the armature motion, a reasonable form of the frictional force was modeled considering the velocity skin effect and the structural analysis. In this paper, the application of the voltage correction method into the rails of an electromagnetic launcher was introduced in detail, and the comparison of the results between the experiments and modified calculations for the constructed launcher system was described.

After preliminary tests using a small 25 mm-caliber electromagnetic launcher, a larger mid-caliber launcher has been designed and fabricated. The launcher has a rectangular bore of 40 mm × 50 mm, where the rails are separated by 50 mm from each other and are 5.6 m long. To deliver an electrical current to the launcher, a new 4.8-MJ pulsed power supply (PPS) consisting of eight 600-kJ segments has been constructed. The 600-kJ segment is a basic building block of PPS operated independently. It contains a controller, a charger, a safety circuit, and six 100-kJ unit modules. Each unit module in the segment is composed of a 100 kJ capacitor bank, a thyristor switch, a crowbar diode, and a pulse-forming inductor. The modules in a segment are charged to the same voltage, but they are designed to have different triggering times to make a flexible shape of current waveform. The electrical parameters of the PPS were determined through the discharges of the unit modules and those of the rails were measured by launch experiments or short circuit tests at the ends of the rails. Launch experiments have been done using several current waveforms. The current of 1 MA in a few milliseconds accelerated the armatures of several hundred grams in mass to velocities near 2 km/s. In this paper, the design and basic performance of the constructed PPS and the electromagnetic launcher are presented.

This study investigated the effect of design parameters of a 2.5 inch HDD on the operational shock (op-shock) performance, including the base, cover, ramp stiffness, and the e-block, disk thickness. First, transient shock simulation model was constructed with a nonlinear contact model. From this shock model, the relative displacement between slider and disk is extracted and the vertical force and moment between the slider and disk are calculated. Then, the slider dynamics were analyzed to investigate the characteristics of the head disk interface (HDI) in response to input shock. The input shock is the pulse that is extracted from the transient shock simulation. Finally, the effects of the design parameters on operational shock performance were investigated.

During PEMFC(Proton Exchange Membrane Fuel Cell) operation monitoring and diagnosis are important issues for reliability and durability. Stack defect can be followed by a critical cell voltage drop in the stack. One method for monitoring the cell voltage is CVM(Cell Voltage Monitoring), where all cells in the stack are electrically connected to a voltage measuring system and monitored these voltages. The other methods are based on the EIS(Electrochemical Impedance Spectroscopy) and on nonlinear frequency response. In this paper, intermodulation(IM) method for diagnosis PEMFC stack is introduced. To detect one or more critical PEMFC cell voltage PEMFC stack is excited by two or more test sinusoid current, and the frequency response of the stack voltage is analyzed. If one or more critical cell voltage exists, higher harmonics on the voltage frequency spectrum will appear. For the proposed IM method, stack simulation and experiments are conducted. Key words : PEMFC stack(양성자교환막 스택), Stack diagnosis(스택 진단), Critical fuel cell voltage(임계 연료전지 전압), Intermodulation(인터모듈레이션)

A combined analytical and numerical method is presented to get a response for an elastically supported Timoshenko beam to a moving load. The analytical steady-state solution as a particular solution is established and summed with the numerically calculated homogeneous solution. A steady-state solution is sought analytically through the direct application of the Fourier transform to the moving step load. It is shown to be a compact formula composed of exponential and sinusoidal functions depending on the load velocity. The homogeneous solution is established numerically to cancel out the discontinuities and the inconsistent boundary and initial conditions of the steady-state solution. The discontinuities produced by the steady-state solution are removed using the physical characteristics related to the bar wave. Some response curves are shown to compare the beam motions at different load velocities.

Since distribution and preservation of cultural artifacts in the submarine sediments are directly affected by not only ocean currents and tides, but also their composition, it is very important to investigate geological characteristics of sediments and ocean-sediment interactions for maritime archaeological survey. Physical properties of submarine sediments, which are collected by grab sampler and vibro-corer, are analyzed in order to investigate effects of submarine environment on development of maritime archaeological survey techniques. Result of physical property analysis showed that bulk density, shear strength, and magnetic susceptibility increase with depth, while water contents and porosity decrease with depth. Since the magnetic susceptibility of bedrock is about 40 times that of submarine sediments, it might impact greatly on the response of magnetic survey. Physical properties of sediments with depth and sediment classification by Folk’s ternary diagram indicate that submarine sediment mainly consists of silt, and cultural artifacts can not penetrate no deeper than 1.5 m in sediments.

Inductive electrical components made of massive conductors are usually adopted in the high-power circuit. Since they are not the types of filaments, the diffusion of the electromagnetic fields inside the conductors plays an important role in the transient discharge. Though the behavior of the circuit can be described reasonably using constant electrical parameters, the voltage drop in the massive conductor is not expressed accurately when constant resistance and inductance are used in the analysis of the transient discharge. To obtain a more accurate waveform of the pulsed current, we have used a comprehensive method calculating the correction voltage in the voltage drop. Once the resistive voltage drop and the magnetic flux for a step-function current are obtained either analytically or numerically, the voltage drop in the massive component for any current waveform can be calculated using the Duhamel's integration. The equations of the circuit containing massive conductors can be solved through a few iterations using the method estimating the voltage drop. As an example, the method was applied to an analysis of an RLC circuit containing a massive pulse-forming inductor. Electromagnetic responses of the inductor for a step-function current were calculated numerically with the help of a finite element method. The current waveform calculated using the method of correction voltage showed a good agreement with the measured waveforms.