• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.2
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• pp.87-93
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• 2022

The demand for metal-polymer joining technology have been increasing, especially in the industrial fields of automotive and aerospace, which require the manufacturing of various lightweight parts. Conventional joining processes have technical hurdles on aspects such as thermal degradation, need for chemical surface treatment, or complicated process settings. These issues can be alleviated by employing interlocking structures for the metal-polymer joined interface. In this study, we joined 3D-printed metal and polymer parts, which were featured with 3D-printed interlocking structures at their interface. By using high frequency induction heating, the joined region could be locally heated to reduce the thermal degradation and distortion of polymer parts. In addition, through the adjustment of interface morphologies and compression conditions, the polymer flow could be optimized to completely fill the interlocking grooves on metal parts, thereby achieving high joining strength. This suggests feasible guidelines for manufacturing metal-polymer joined structures involving 3D-printed architectures.

• Molecules and Cells
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• v.45 no.2
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• pp.84-92
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• 2022

To understand the microcircuitry of the brain, the anatomical and functional connectivity among neurons must be resolved. One of the technical hurdles to achieving this goal is that the anatomical connections, or synapses, are often smaller than the diffraction limit of light and thus are difficult to resolve by conventional microscopy, while the microcircuitry of the brain is on the scale of 1 mm or larger. To date, the gold standard method for microcircuit reconstruction has been electron microscopy (EM). However, despite its rapid development, EM has clear shortcomings as a method for microcircuit reconstruction. The greatest weakness of this method is arguably its incompatibility with functional and molecular analysis. Fluorescence microscopy, on the other hand, is readily compatible with numerous physiological and molecular analyses. We believe that recent advances in various fluorescence microscopy techniques offer a new possibility for reliable synapse detection in large volumes of neural circuits. In this minireview, we summarize recent advances in fluorescence-based microcircuit reconstruction. In the same vein as these studies, we introduce our recent efforts to analyze the long-range connectivity among brain areas and the subcellular distribution of synapses of interest in relatively large volumes of cortical tissue with array tomography and superresolution microscopy.

• Journal of Trauma and Injury
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• v.36 no.4
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• pp.322-328
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• 2023

Purpose: Patients with multiple trauma necessitate assistance from a wide range of departments and professions for their successful reintegration into society. Historically, the primary focus of trauma treatment in Korea has been on reducing mortality rates. This study was conducted with the objective of evaluating the current state of multidisciplinary treatment for patients with severe trauma in Korea. Based on the insights of trauma specialists (i.e., medical professionals), we aim to suggest potential improvements. Methods: An online questionnaire was conducted among 871 surgical specialists who were members of the Korean Society of Traumatology. The questionnaire covered participant demographics, current multidisciplinary practices, perceived challenges in collaboration with rehabilitation, psychiatry, and anesthesiology departments, and the perceived necessity for multidisciplinary treatment. Results: Out of the 41 hospitals with which participants were affiliated, only nine conducted multidisciplinary meetings or rounds with nonsurgical departments. The process of transferring patients to rehabilitation facilities was not widespread, and delays in these transfers were frequently observed. Financial constraints were identified by the respondents as a significant barrier to multidisciplinary collaboration. Despite these hurdles, the majority of respondents acknowledged the importance of multidisciplinary treatment, especially in relation to rehabilitation, psychiatry, and anesthesiology involvement. Conclusions: This survey showed that medical staff specializing in trauma care perceive several issues stemming from the absence of a multidisciplinary system for patient-centered care in Korea. There is a need to develop an effective multidisciplinary treatment system to facilitate the recovery of trauma patients.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.6
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• pp.1619-1637
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• 2024

In today's highly digitized landscape, securing digital communication is paramount due to threats like hacking, unauthorized data access, and network policy violations. The response to these challenges has been the development of cryptography applications, though many existing techniques face issues of complexity, efficiency, and limitations. Notably, sophisticated intruders can easily discern encrypted data during transmission, casting doubt on overall security. In contrast to encryption, steganography offers the unique advantage of concealing data without easy detection, although it, too, grapples with challenges. The primary hurdles in image steganography revolve around the quality and payload capacity of the cover image, which are persistently compromised. This article introduces a pioneering approach that integrates image steganography and encryption, presenting the BitPatternStego method. This novel technique addresses prevalent issues in image steganography, such as stego-image quality and payload, by concealing secret data within image pixels with identical bit patterns as their characters. Consequently, concerns regarding the quality and payload capacity of steganographic images become obsolete. Moreover, the BitPatternStego method boasts the capability to generate millions of keys for the same secret message, offering a robust and versatile solution to the evolving landscape of digital security challenges.

• New & Renewable Energy
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• v.20 no.1
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• pp.38-51
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• 2024

The rapid expansion of industrialization and population growth worldwide has led to a significant surge in energy demand, perpetuating heavy reliance on finite fossil fuel reserves. Although prevailing policies primarily target ground-mounted solar photovoltaics, there is a noticeable increase in the adoption of floating solar power generation systems on water surfaces. Nonetheless, adequate studies and legislative reviews on offshore solar photovoltaics in Korea are lacking. The absence of well-defined criteria for the economic analysis of floating solar photovoltaics presents hurdles to their economic feasibility. This study conducted a comprehensive cost-benefit analysis of offshore photovoltaics to evaluate their economic viability and compared four types of solar photovoltaics based on the operating area and technology: ground-mounted, floating on inland water, pontoon-based offshore, and flexible system offshore. Perspectives from both central and local government entities, emphasizing social aspects, as well as inputs from private companies with a financial focus were considered. The findings revealed variations in economic viability depending on the operating area and technology employed. This study aims to contribute to the advancement of market maturity and technology within the realm of offshore solar photovoltaics.

• Transactions of Materials Processing
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• v.33 no.3
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• pp.208-213
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• 2024

Ni-based superalloys have exceptional performance in high-temperature strength, corrosion resistance, etc, and it has been widely used in various applications that require corrosion resistance at high-temperature operations. However, the relatively expensive cost of the Ni-based superalloys is one of the major hurdles. The corrosion-resisted alloy(CRA) clad materials can be a cost-effective solution. In this study, finite element analysis of the hot rolling process for manufacturing of the Alloy 625/API X65 steel CRA clad plates is conducted. The stress-strain curves of the two materials are measured in compressive tests for various temperature and strain rate conditions, using the Gleeble tester. Then, strain hardening behavior is modeled following the modified Johnson-Cook model. Finite element analysis of the hot rolled cladding process is performed using this strain rate and temperature dependent hardening model. Finally, the thickness ratio of the CRA and base material is predicted and compared with experimental values.

• International Journal of Advanced Culture Technology
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• v.12 no.3
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• pp.140-147
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• 2024

Oil and gas industry is a unique sector with complex activities, long supply chains and strict rules for the business. It is important to use enterprise resource planning (ERP) systems to address these challenges as it helps in simplifying operations, improving efficiency and facilitating evidence-based decision making. Nonetheless, successful integration of ERP systems in this industry involves careful planning, customization and alignment with specific business processes including regulatory requirements. Several critical factors, such as strong change management, support of top managers and training that works have been identified in the study. Amongst the hurdles are employee resistance towards the changes, data migration complications and integration with existing systems. Nonetheless, NOCL's ERP implementation resulted in significant improvements in operating efficiency, better data visibility and compliance management. It also led to a decrease in financial reporting timeframes, more accurate inventory tracking and improved decision-making capabilities. The study provides useful insights on how to optimize oil and gas sector ERP implementations; key among them is practical advice including strengthening change management strategies, prioritizing data security and collaborating with ERP vendors. The research highlights the importance of tailoring ERP solutions to specific industry needs as well as emphasizes the strategic role of ongoing monitoring/feedback for future benefits sustainability.

• Journal of Digital Convergence
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• v.12 no.4
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• pp.103-113
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• 2014

Bargain position and trust are core issues in supply chain management, yet the effect of bargain position on trust remains to be undetermined. The purpose of this research is to present theoretical and methodological hurdles for the relationship among various bargain positions and trust, and develops a set of hypotheses about the asymmetric effect of bargain position on trust in supply chain network. An analytical tool to analyze nonlinear effects on a response surface is introduced. Based on the data collected through a survey of firms participating in Project Supply chain, a set of hypotheses is tested. The analysis results support the prediction that the bargain position perceived by the buyers have asymmetric effects on trust toward supplies, and provide more fine-grained accounts on the relationships among bargain power, bargain position and trust in a supply chain network.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.812-819
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• 2015

Gladiolus is one of the most popular cut flowers in the world floral market and is highly attractive to consumers. The production of poor-quality gladiolus spikes is one of the most important hurdles to obtaining high prices for this crop. The main objectives of this study were to improve the quantitative characteristics of gladiolus spikes, to increase propagule production and to enhance chemical constituent levels in leaves to help improve plant growth. We performed foliar application of bioregulators, including polyamines (putrescine and spermine) and vitamins (ascorbic acid and thiamine), at different concentrations (0, 0.1, 0.4, 0.7 and 1 mM) to gladiolus plants at the three leaf, five leaf and slipping stages. Application of 1 mM putrescine was the most effective treatment, with prominent effects on economically important spike traits including spike length (55.53 cm), spike diameter (7.53 mm), florets per spike (13.99), first floret diameter (9.66 cm) and first floret weight (4.90 g), followed by spermine treatment. The 1 mM putrescine treatment also had positive effects on corm-associated traits including corm diameter and corm weight, with values of 4.57 cm and 26.16 g compared to 3.47 cm and 17.16 g in control plants, respectively. The contents of chemical constituents in leaves, including total chlorophylls ($8.06mg{\cdot}g^{-1}$), total carotenoids ($1.66mg{\cdot}g^{-1}$), total soluble sugars ($4.75 mg{\cdot}g^{-1}$) and phenolics ($0.89mg{\cdot}g^{-1}$) increased in response to foliar application of 1 mM putrescine compared to the control. Ascorbic acid and thiamine also had positive effects on various plant morphological traits and chemical constituents in leaves compared to control plants, but the growth-promoting effects of polyamines were more pronounced. Hence, applying polyamines to gladiolus leaves will help improve spike production and increasing propagule (cormel) yields.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.2
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• pp.1-13
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• 2015

The Coupled Model Intercomparison Project Phase 5 (CMIP5), coordinated by the World Climate Research Programme in support of the Intergovernmental Panel on Climate Change (IPCC) AR5, is the most recent, provides projections of future climate change using various global climate models under four major greenhouse gas emission scenarios. There is a wide selection of climate models available to provide projections of future climate change. These provide for a wide range of possible outcomes when trying to inform managers about possible climate changes. Hence, future agrometeorological indicators estimation will be much impacted by which global climate model and climate change scenarios are used. Decision makers are increasingly expected to use climate information, but the uncertainties associated with global climate models pose substantial hurdles for agricultural resources planning. Although it is the most reasonable that quantifying of the future uncertainty using climate change scenarios, preliminary analysis using reasonable factors for selecting a subset for decision making are needed. In order to narrow the projections to a handful of models that could be used in a climate change impact study, we could provide effective information for selecting climate model and scenarios for climate change impact assessment using maximum/minimum temperature, precipitation, reference evapotranspiration, and moisture index of nine Representative Concentration Pathways (RCP) scenarios.