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A set of vertices in a graph dominates if every vertex in is either in or adjacent to a vertex in . The size of any smallest dominating set is called domination number of . The concept of Medium Domination Number was introduced by Vargor and Dunder which finds the total number of vertices that dominate all pairs of vertices and evaluate the average of this value. The Medium domination Number is a notation which uses neighbourhood of each pair of vertices. For G = (V, E) and ∀u,v∈ V if u, v are adjacent they dominate each other, then atleast dom (u, v) = 1. The total number of vertices that dominate every pair of vertices is defined as TDV(G)=∑dom(u,v), for every u,v∈V(G). For any connected, undirected, loopless graph G of order p, the Medium Domination Number MD(G) = . In this paper we have introduced the new concept Medium Domination Decomposition. A decomposition of a graphG is said to be Medium Domination Decomposition (MDD) if

Typhoons, fueled by warm sea surface waters, heighten concern as they increasingly interact with frequent Marine Heatwaves (MHWs) in a changing climate. Typhoon Hinnamnor (2022) weakened and re‐intensified as it approached the Korean Strait, interacting with an underlying MHW in the northern East China Sea (nECS). In‐situ observations and reanalysis products revealed a significant increase in latent heat loss from the nECS during the MHW period, contributing to the typhoon re‐intensification. Strong sea surface wind forcing with the typhoon enhanced vertical mixing and upwelling, resulting in a pronounced (0.90°C) sea surface cooling after the typhoon passage, facilitating MHW disappearance with reduced thermal stratification. During MHWs, increased background stratification increases temperature oscillations associated with semidiurnal internal tides. Furthermore, post‐typhoon changes in stratification weakened semidiurnal internal tides due to unfavorable conditions for generation from a nearby source. These findings highlight the importance of continuous time‐series observations to monitor interactions among climatic extremes. Plain Language Summary: Typhoons, powered by warm ocean waters, are causing more concern as they increasingly interact with frequent episodes of extremely warm sea conditions known as Marine Heatwaves (MHWs) in a changing climate. This study focuses on Typhoon Hinnamnor in 2022, which went through a weakening and then strengthened as it moved to the Korean Strait and encountered an MHW in the northern East China Sea (nECS). By using in‐situ data collected in the nECS and additional data analysis, we discovered a significant increase in heat loss from the nECS during the MHW, contributing to the intensification of typhoon. The powerful winds from the typhoon caused enhanced mixing and cooling of the sea surface after it passed, helping to cause the disappearance of the MHW and reduce the layering of temperatures in the ocean. During MHW, strong layering strengthens the temperature oscillation linked with the semidiurnal internal tides in the ocean. After typhoon passage there is a decrease in the layering in the ocean, thus weakening the internal tide. The study emphasizes the importance of continuous observations to understand and monitor these interactions in our changing climate. Key Points: Typhoon Hinnamnor (2022) re‐intensified after interacting with the underlying Marine Heatwave (MHW) in the East China SeaTyphoon wind‐driven mixing caused the disappearance of the underlying MHWStratification change accompanied by MHW, and typhoon reduced the local activities of semidiurnal internal tides [ABSTRACT FROM AUTHOR]

During the summer of 2016, the northern East China Sea and the southern Yellow Sea (NECS‐SYS) experienced one of the most severe and devastating marine heatwaves (MHWs) on record, with a temperature anomaly exceeding 4°C. This shallow semi‐enclosed continental shelf region is widely recognized as a significant hotspot for MHWs with associated incidences of harmful algae blooms. Previous studies have highlighted the importance of mixed layer shoaling as a crucial factor in the genesis of MHWs in the global ocean. The current study employed the Hybrid Coordinate Ocean Model reanalysis data set during 1994–2015 to delve into the mechanisms driving mixed layer shoaling during NECS‐SYS MHW genesis. Our findings reveal the significant role of the northward propagating boreal summer intraseasonal oscillation in promoting MHW genesis and intensification. Specifically, boreal summer intraseasonal oscillation phases 5, 6, and 7 contribute to the favorable conditions that facilitate MHW formation by inducing mixed layer shoaling and increasing solar influx, with mixed layer shoaling playing a more dominant role. The current study provides insights into the relative influences of wind, salinity, and temperature on mixed layer shoaling. We observe that wind plays the most significant role in mixed layer shoaling, followed by temperature and salinity. The boreal summer intraseasonal oscillation induced wind relaxation, increased shortwave radiation, and freshwater influx lead sea surface temperature by 7, 5, and 4 days, respectively. Importantly, mixed layer shoaling leads SST anomalies by 1–2 days. Therefore, the current study also suggests an intraseasonal predictability source for NECS‐SYS MHWs. Plain Language Summary: The northern East China Sea and southern Yellow Sea (NECS‐SYS) experienced one of the most severe and devastating marine heatwaves (MHWs) during the summer of 2016. The region, situated in the northwest Pacific, is characterized by a shallow semi‐enclosed marginal sea, and receives a significant amount of freshwater influx from the Yangtze River. Previous studies have demonstrated that shoaling of surface mixed layer is a primary factor contributing to the genesis of MHWs in the global ocean. The present study emphasizes the role of the boreal summer intraseasonal oscillation in creating favorable conditions for MHWs genesis in these regions. Our research demonstrates that boreal summer intraseasonal oscillation phases 5, 6, and 7 contribute to the amplification of solar flux and the shoaling of mixed layer by reducing wind speed and introducing freshwater in this region. We provide a comprehensive understanding of the individual influences of wind, salinity, and temperature on mixed layer shoaling, highlighting the significance of mixed layer shoaling as a fundamental driver of MHWs. Moreover, our research also directs to an intraseasonal predictability source of the NECS‐SYS MHWs. Key Points: Boreal Summer Intraseasonal Oscillation phases 5, 6, and 7 facilitate marine heatwaves (MHWs) in the northern East China Sea and southern Yellow SeaMixed layer shoaling is a more critical factor than the enhanced shortwave for MHW genesis and intensification in this regionOccurrences of MHWs in phase with boreal summer intraseasonal oscillation offer subseasonal predictability of MHWs [ABSTRACT FROM AUTHOR]

AISI 304 stainless steel categorized under austenitic, has good resistance to corrosion and applicable for high resistance to pitting and stresses. But it has poor hardness, sterngth and resistance to wear. In order to overcome the above problem, various hardening techniques like nitriding, carburizing, carbonitriding, Cyaniding etc are preferred. In this work, aqueous soluted nitriding process is carried out to improve the surface hardness and wear resistance on AISI 304 specimens. Three specimens in cylindrical shape with a diameter of 10mm and length 35mm are treated with salt bath nitriding process for a time period of 45 minutes, 90 minutes, 120 minutes and named as SBN 1, SBN 2, SBN 3 respectively. One specimen is kept untreated to compare the results with treated specimens. After the heat treatment procedure is completed, pin on disc wear testing instrument was used to conduct a wear test at a constant speed and load. All the specimens were subjected to Scanning Electron Microscope test and the results were compared.

Stainless steel is well known for its good corrosion resistance. It is easily available in the market at low cost. Martensitic stainless steels are hard and brittle in nature, it lacks ductility. Therefore hardness, brittleness, ductility has to be balanced in martensitic stainless steel. Annealing is chosen for this research work to maintain balance between ductility and brittleness. Martensitic stainless steel samples were cut into five small pieces of length 40 mm and diameter 12 mm each by using a lathe machine. Annealing process were carried out for three specimens to the temperature 7200C, 8200C, 9200C and were named as AN1, AN2, AN3 respectively. One sample is kept aside as untreated for comparison purpose. A wear test was performed on all specimens using a pin-on-disc wear tester to evaluate the material’s wear resistance. The results of all samples were compared using a scanning electron microscope and the best material is chosen for the required application.