Latest news with #DonggukUniversity
Yahoo
13-04-2025
- Science
- Yahoo
Lithium-ion batteries offer longer lifespan, fast charging with nanoscale engineering
South Korean researchers from Dongguk University, in collaboration with Kyungpook National University in Daegu, have dramatically improved lithium-ion battery technology using nanoscale engineering. According to reports, their innovations have successfully enhanced the technology's energy storage and cycling stability, addressing the growing demand for efficient energy solutions. A collaborative research effort led by Professor Jae-Min Oh of Dongguk University and Professor Seung-Min Paek of Kyungpook National University has resulted in a novel battery anode material that promises significant performance gains. Their findings, published in the Chemical Engineering Journal, focus on a new hybrid composite material engineered at the nanoscale to optimize conductivity and stability. The innovation's heart is a hierarchical heterostructure composed of reduced graphene oxide (rGO) and nickel-iron layered double hydroxides (NiFe-LDH). Each component brings distinct advantages. Reduced graphene oxide is a high-speed highway for electrons, while the nickel-iron elements store charge through a fast pseudocapacitive mechanism. Lithium-ion batteries have become the workhorses of modern energy storage, powering everything from smartphones and laptops to electric vehicles and renewable energy grids. However, the push for better performance, higher energy density, faster charging, and longer lifespan continues to drive global research and innovation. What sets this new material apart is its unique structure, which is rich in grain boundaries that enhance charge storage and transport. The researchers employed a meticulous layer-by-layer self-assembly process using polystyrene (PS) beads as templates. These beads were first coated with graphene oxide and NiFe-LDH precursors. Once the templates were removed, a thermal treatment transformed the nickel-iron layers into nanocrystalline nickel-iron oxide (NiFe₂O₄) and amorphous nickel oxide (a-NiO) while also reducing the GO into conductive rGO. The result is a hollow, sphere-like structure where the active materials are well-integrated and protected, offering high conductivity and degradation resistance. According to the research team, advanced imaging and analytical techniques, including X-ray diffraction and transmission electron microscopy, confirmed the structure and composition of the material. Moreover, electrochemical testing revealed impressive results: the new anode delivered a high specific capacity of 1687.6 mA h g⁻¹ at 100 mA g⁻¹, even after 580 charge/discharge cycles. The scientists claim this outperforms many existing materials and suggests excellent longevity and real-world performance. The design's hollow structure improves stability by preventing direct contact between active nanoparticles and the battery's electrolyte, which is often a cause of capacity fade over time. 'This breakthrough was made possible through close cooperation between experts in diverse materials,' said Professor Paek. 'By combining our strengths, we could design and optimize this hybrid system more effectively." 'We believe the future of energy storage lies not just in improving single materials but in developing systems of interacting materials that produce synergistic effects. This research shows a clear path toward smaller, lighter, and more efficient batteries," he added. The team's work could lead to commercial battery technologies that deliver longer life, faster charging, and improved performance in everything from electric vehicles to grid-scale storage, potentially within the next five to ten years. As the global demand for cleaner, more efficient energy grows, innovations like this offer a promising glimpse into what's possible. You can view the study in Chemical Engineering Journal.
Korea Herald
06-04-2025
- Politics
- Korea Herald
Ruling week ends with chaos-free protests
In contrast to the violent unrest that followed the Constitutional Court's 2017 dismissal of President Park Geun-hye — which left four people dead — the public response to President Yoon Suk Yeol's ouster on Friday has been largely calm, with protests remaining peaceful and orderly. Aside from two isolated incidents — a man in his 20s attempting to break a police bus window with a baton, and a reported self-immolation attempt near the presidential residence in Hannam-dong — the overall atmosphere at major rally sites in Seoul, including Anguk Station, Gwanghwamun, and Hannam-dong, remained calm. No illegal protests or serious challenges to public order were reported. Yoon's supporters and detractors expressed their emotions, but there was no form of violence involved. Professor Lim Joon-tae from the Department of Police Administration at Dongguk University was quoted by News1 as saying that the police authorities' concrete measures, including sealing off the Constitutional Court and invoking the highest alert level in the police emergency response system, effectively prevented physical confrontations among demonstrators amid the intense standoff between political extremes. Lim explained that the shocking attack on the Seoul Western District Court in January served as a lesson, allowing the police to allocate more personnel and security equipment to ensure public safety and maintain order. Mobile police squads and investigators were tasked with arresting protestors who broke into the court building and protecting the court justices. Some 14,000 officers in mobile police squads -- the units used for crowd control -- were deployed. Allocating a total of 513 Seoul firefighter paramedics and 84 ambulances was another of many measures to prepare for emergencies. Acting Chief Justice of the Constitutional Court Moon Hyung-bae also expressed gratitude to the police for ensuring the court's safety during Yoon's impeachment trial. While acknowledging the authorities' efforts to ensure public safety, Lee Joo-hee, a professor in the Sociology Department at Ewha Womans University, believes that the mostly subdued rallies on Friday highlighted the country's mature democracy. 'People say that South Korea today is divided in almost every area, ranging from politics to age and gender issues. But we were able to see that many social groups, including minorities like young women and farmers, successfully made their voices heard without violence,' Lee told The Korea Herald. 'People from all walks of life joined in solidarity and sacrificed themselves to protect the democratic system that was fought for and won against authoritarian leaders in the past. Though the political divide was considered more intense than that of Park Geun-hye's case, both pro- and anti-Yoon protestors seemed to accept the court's decision without threatening public authority. This can certainly be seen as the country's mature democracy,' the professor added. But Lee believes danger still lurks. 'We have seen some ruling People Power Party lawmakers join hands with far-right figures like Jun Kwang-hoon – a controversial church leader -- and stoke mistrust, confusion and enmity among each other. Such actions need to be stopped to prevent incidents like what happened at the Seoul Western District Court,' she said.
Korea Herald
19-03-2025
- Politics
- Korea Herald
False rumors about police spread ahead of ruling
False rumors about police deployed to protest sites is spreading among right-wing social media users, fueling conspiracy theories ahead of South Korean President Yoon Suk Yeol's impeachment ruling. On social media platforms such as X, photos of mobile police squad officers with long or bleached hair have spread, with claims alleging that such police are not Korean, but Chinese nationals. Referring to a screenshot of what appears to be the AI-generated response of an unknown large language model tool about police grooming regulations, one post on X claimed that a police officer must have 'neatly groomed hair,' with male police officers having hair that is no longer than 7 centimeters at the front and does not touch the ears or the collar. The screenshot says police are also not allowed to dye their hair any color except black. There was no source given for the screenshot. However, Article 5 of the Police Officials Service Regulations only states that 'officers must maintain a neat appearance and dress appropriately to uphold their dignity,' without specifying any detailed rules about hairstyles. A police official also confirmed to The Korea Herald that there are no internal rules that prohibit officers from having long or dyed hair. Despite the actual rules differing substantially from those in the screenshot, posts claiming police officers with long or bleached hair are 'not real police officers' are still circulating on social media. 'A Korean police officer with long hair? As a South Korean national with common sense, this man is 100 percent not a Korean police officer, but is Chinese,' wrote one user on X. Recently, conspiracy theories have emerged on social media platforms in Korea, such as far-right YouTube channels and online forums, claiming that the police are 'infiltrated by leftists' or 'fake Chinese agents.' Anti-China sentiment is common among right-wing circles, along with claims that China is "interfering" in Korean politics, economics and media narratives. Supporters of the suspended president have clashed with law enforcement during their protests, accusing police of unjustly suppressing their demonstrations while being lenient toward groups they perceive as "pro-China" or "commies." Experts warn that fake news, especially those that target law enforcement, should be regulated, as it can lead to the 'weakening of public trust in law enforcement and the police force.' 'Fake news ridiculing or undermining law enforcement can diminish police authority and public trust in law enforcement,' Kwak Dae-kyung, a professor in Dongguk University's Department of Police Administration, told The Korea Herald. 'The spread of such misinformation targeting law enforcement must be countered, as it could create social disorder and hinder effective law enforcement efforts. The repeated spread of distorted information about minor issues surrounding the police shouldn't be left ignored, as it could ultimately extend to a general distrust of the entire police force, which could significantly weaken the ability of law enforcement to uphold social order," he said.
Korea Herald
19-03-2025
- Politics
- Korea Herald
Fake news about police spreads ahead of impeachment ruling
Fake news about police officers stationed at protest sites is spreading among the far right on social media, fueling conspiracy theories as pro- and anti-impeachment protests have continued ahead of suspended South Korean President Yoon Suk Yeol's impeachment ruling. On social media platforms such as X, photos of mobile police squad officers with long or bleached hair have spread, with claims alleging that such police are not Korean, but Chinese nationals. Referring to a screenshot of what appears to be the AI-generated response of an unknown large language model tool about police grooming regulations, one post on X claimed that a police officer must have 'neatly groomed hair,' with male police officers having 'bangs that are no longer than 7 centimeters' as well as side hair and back hair not touching the ears or the collar. Police dyeing their hair, according to the screenshot, is also not allowed except for black. There was no source given for the screenshot. However, Article 5 of the Police Officials Service Regulations only states that 'officers must maintain a neat appearance and dress appropriately to uphold their dignity,' without specifying any detailed rules about hairstyles. A police official also confirmed to The Korea Herald that there are no internal rules that prohibit officers from having long or dyed hair. Despite the actual rules differing substantially from those in the screenshot, posts nonetheless claiming police officers with long or bleached hair are 'not real police officers' are still circulating on social media. 'A Korean police officer with long hair? As a South Korean national with common sense, this man is 100 percent not a Korean police officer, but is Chinese,' wrote one user on X. Recently, conspiracy theories have emerged on social media platforms in Korea, such as far-right YouTube channels and online forums, claiming that the police are 'infiltrated by leftists' or 'fake Chinese agents.' The conspiracy theories are seen to come from anti-China sentiment among far-right Koreans based on fears that allege China is "interfering" in Korean politics, economy and media narratives. Based on such misinformation, supporters of the suspended president have clashed with law enforcement during their protests, who believe the police are 'unjustly' suppressing their demonstrations while being 'lenient' toward groups they perceive as "pro-China" or "commies." Experts warn that fake news, especially those that target law enforcement, should be regulated, as it can lead to the 'weakening of public trust in law enforcement and the police force.' 'Fake news ridiculing or undermining law enforcement can diminish police authority and public trust in law enforcement,' Kwak Dae-kyung, a professor in Dongguk University's Department of Police Administration, told The Korea Herald. 'The spread of such misinformation targeting law enforcement must be countered, as it could create social disorder and hinder effective law enforcement efforts. The repeated spread of distorted information about minor issues surrounding the police shouldn't be left ignored, as it could ultimately extend to a general distrust of the entire police force, which could significantly weaken the ability of law enforcement to uphold social order," he said.
