Showing papers by "Republic of Korea Army published in 2021"

Dominant design and evolution of technological trajectories: The case of tank technology, 1915–1998

Abstract: This study examines the evolution of product-based technological trajectories by linking technology and socioeconomic factors. Products evolve to adapt to market conditions in a manner similar to biological evolution, and form a constant trajectory under the influence of the current technological paradigm. This study analyzes the changes in technological trajectories after the emergence of a dominant design in the core weapon of the army—armored tanks. Based on a case study of the evolution of tanks between 1915 and 1998 and the application of principal component analysis (PCA, to transform technological characteristics of tanks into product performance) and K-means clustering (to classify the types of tanks based on the PCA), we find that tanks have evolved into a common pattern of product evolution and the main battle tank concept plays a role as the dominant design. In addition, military tactical doctrines and capability requirements are used to explain the socioeconomic factors at the core of the technological paradigm behind tank development. We argue that the interaction between science, technology, and the social element is responsible for product evolution. In the case of tanks, moreover, we show that the product evolution process follows continuous changes in the technological trajectory resulting from technological advances. This study also derives policy implications for weapons system acquisition.

CGE analysis of R&D investment policy considering trade-offs between economic growth and stability

Abstract: This study analysed economic growth and industrial structure under different conditions on research and development (R&D) investment. To simulate counterfactual scenarios, we built a recursive dynamic computable general equilibrium model named as Technology and Economy Modelling for Innovation Policy assessment (TEMIP) that focuses on private and public R&D investments and their net effects from a macroeconomic perspective. The simulation shows gross domestic product increases rapidly in South Korea when a given amount of expenditure is spent on public R&D activities rather than private R&D. Moreover, our simulation results imply that resource allocation for R&D investments should be elaborated through considering whether the ultimate policy goal is oriented towards economic growth or stability.

Mitigating Ischemia-Reperfusion Injury Using a Bilobed Partial REBOA Catheter: Controlled Lower-Body Hypotension.

Abstract: BACKGROUND Non-compressible torso hemorrhage (NCTH) is the leading cause of potentially preventable death on the battlefield. Resuscitative endovascular balloon occlusion of the aorta (REBOA) aims to restore central blood pressure and control NCTH below the balloon, but risks ischemia-reperfusion injury to distal organs when prolonged. We tested a bilobed partial REBOA catheter (pREBOA), which permits some of the blood to flow past the balloon. METHODS Female swine (n = 37, 6 groups, n = 5-8/group), anesthetized and instrumented, were exponentially hemorrhaged 50% of estimated blood volume (all except time controls [TC]). Negative controls (NC) did not receive REBOA or resuscitation. Positive controls (PC) received retransfusion after 120 min. REBOA groups received REBOA for 120 min, then retransfusion. Balloon was fully inflated in the full REBOA group (FR), and was partially inflated in partial REBOA groups (P45 and P60) to achieve a distal systolic blood pressure of 45 mm Hg or 60 mm Hg. RESULTS Aortic occlusion restored baseline values of proximal mean arterial pressure, cardiac output, and carotid flow in pREBOA groups. Lactate reached high values during occlusion in all REBOA groups (9.9 ± 4.2, 8.0 ± 4.1, and 10.7 ± 2.9 for P45, P60, and FR), but normalized by 6 to 12 h post-deflation in the partial groups. All TC and P60 animals survived 24 h. The NC, PC, and P45 groups survived 18.2 ± 9.5, 19.3 ± 10.6, and 21.0 ± 8.4 h. For FR animals mean survival was 6.2 ± 5.8 h, significantly worse than all other animals (P < 0.01, logrank test). CONCLUSIONS In this porcine model of hemorrhagic shock, animals undergoing partial REBOA for 120 min survived longer than those undergoing full occlusion.

Ultralow-Power Receivers: Overcoming Battery Limitations to Facilitate Self-Powered Operation

Abstract: Fast forward to a world with 1 trillion wirelessly connected devices in which pervasive computing impacts every aspect of our lives. Now imagine that each of those devices operates on a battery that lasts an average of three years, which is very generous considering that most of today's Internet of Things (IoT) devices have batteries with much shorter lives. In that world, we would be changing 1 billion batteries per day just to maintain the network of devices. Setting aside for the moment the environmental impact of battery disposal at that scale, nobody wants to take on the battery maintenance problem. Today, this is what limits the mass adoption of IoT solutions. It is why factories have not installed monitors on their 10,000 assets and why shipping companies do not embed real-time tracking in every package label. When you examine the power consumption of IoT devices over their lifetime, most of the energy is used for wireless communication; of that electricity, a large amount is spent on network synchronization rather than transmitting data. This calls for better networking solutions to enable massive scales of devices and ultralow-power (ULP) radios to enable self-powered operation, eliminating the battery and, therefore, the maintenance problem.

Association between insulin resistance and lung function trajectory over 4 years in South Korea: community-based prospective cohort

Abstract: Hyperglycemic conditions are associated with respiratory dysfunction Although several studies have reported that insulin resistance (IR) is related to decreased lung function, the association between IR and change in lung function has been rarely studied This study aimed to investigate the potential association of IR on annual change in lung function using a community-based prospective cohort in Korea We selected 4827 Korean participants whose serial lung functions were assessed over 4 years using 1:3 propensity score matching Exposure was baseline IR estimated with homeostatic model assessment (HOMA-IR), and outcomes were annual changes in lung function determined by calculating the regression coefficient using least-square linear regression analysis In the multivariate linear regression, per one unit increased log transformed HOMA-IR was associated with decline in FEV1%-predicted (β: − 023, 95% CI: − 036 to − 011) and FVC %-predicted (β: − 020, 95% CI: − 033 to − 008), respectively In the generalized additive model plot, HOMA-IR showed a negative linear association with annual changes in FEV1%-predicted and FVC %-predicted The suggested threshold of HOMA-IR for decline in lung function was 10 unit for annual change in FEV1%-predicted and 22 unit for annual change in FVC %-predicted Age showed statistically significant effect modification on the relationship between HOMA-IR and annual change in FEV1%-predicted Increased HOMA-IR was associated with the decreased annual change in FEV1%-predicted, particularly in older people In South Korea, increased HOMA-IR was associated with decline in lung function Since IR was related to decline in FEV1%-predicted, particularly in older people, tailored approaches are needed in these populations The potential pulmonary hazard of IR needs to be confirmed in future studies

An Optimization Approach to Minimize the Expected Loss of Demand Considering Drone Failures in Drone Delivery Scheduling

Abstract: This study proposes a drone-based delivery schedul- ing method considering drone failures to minimize the expected loss of demand (ELOD). An optimization model (DDS-F) is developed to determine the assignment of each drone to a subset of customers and the corresponding delivery sequence. Because solving the optimization model is computationally challenging, a Simulated Annealing (SA) heuristic algorithm is developed to reduce the computational time. The proposed SA features a fast initial solution generation based on the Petal algorithm, a binary integer programming model for path selection, and a local neigh- borhood search algorithm to find better solutions. Numerical results showed that the proposed approach outperformed the well-known Makespan problem in reducing the ELOD by 23.6% on a test case. Several case studies are conducted to illustrate the impact of the failure distribution function on the optimal flight schedules. Furthermore, the proposed approach was able to obtain the exact solutions for the test cases studied in this paper. Numerical results also showed the efficiency of the proposed algorithm in reducing the computational time by 44.35%, on average, compared with the exact algorithm.

Support from superiors reduces depression in Republic of Korea military officers.

Abstract: Background The prevalence of depression is relatively high in the Korean military. Social support is a protective factor against depression and is classified into four categories: emotional support—having the sense of feeling loved; instrumental support—receiving material assistance; informational support—receiving advice; appraisal support—feeling valued and respected for one9s abilities. Objective To investigate the effect of support from one’s superior on depression among Republic of Korea (ROK) military officers. Methods 2047 participants from the 2015 Military Health Survey were included in the study. The Korean version of the Beck Depression Inventory was used to measure depression, and a self-reported questionnaire was used to assess support from one’s superior. A chi-squared test and multiple logistic regression were used to analyse the data. Results Of the 2047 participants, 177 (8.6%) had depression. Military officers who did not receive support from their superior were more likely to have depression than than those who did receive support (OR=2.09, 95% CI 1.30 to 3.36). Additionally, military personnel who did not receive emotional or appraisal support were more likely to have depression (emotional support: OR=2.37, 95% CI 1.31 to 4.29; appraisal support: OR=1.56, 95% CI 1.48 to 2.75). Conclusions Our study found that depression in military officers was associated with lack of support from superiors. In particular, emotional support and appraisal support had a statistically significant effect. Therefore, we suggest that the ROK armed forces consider early intervention and management for high-risk groups. A social support programme and organisational atmosphere are also needed to improve supportive ability and skills of superiors.

Wnt signalling inhibits adipogenesis in orbital fibroblasts from patients with Graves' orbitopathy

Abstract: Background/Aims To investigate the role of Wnt signalling in adipogenesis using an in vitro model of Graves’ orbitopathy (GO). Methods Orbital fat was obtained from patients with GO and non-GO participants for primary orbital fibroblast (OF) culture. Expression levels of Wnt5a, Wnt10b, β-catenin, phospho-β-catenin and cyclin D1 were compared between GO and non-GO OFs. These expression levels were also determined during adipogenesis of GO and non-GO OFs. The effects of a stimulator and inhibitor of Wnt signalling on adipogenesis of GO and non-GO OFs were investigated. Results Western blotting analysis showed significant reductions in β-catenin and cyclin D1 and significant enhancement of phospho-β-catenin in OFs from patients with GO, compared with OFs from non-GO participants (p Conclusion These results indicate that Wnt signalling inhibits adipogenesis in OFs from patients with GO and non-GO participants. Further studies are required to examine the potential of Wnt signalling as a target for therapeutic strategies.

An Integrated Model including the ROX Index to Predict the Success of High-Flow Nasal Cannula Use after Planned Extubation: A Retrospective Observational Cohort Study.

Abstract: High-flow nasal cannula (HFNC) therapy is commonly used to prevent reintubation after planned extubation. In clinical practice, there are no appropriate tools to evaluate whether HFNC therapy was successful or failed after planned extubation. In this retrospective observational study, we investigated whether the use of the ROX index was appropriate to differentiate between HFNC success and failure within 72 h after extubation and to develop an integrated model including the ROX index to improve the prediction of HFNC success in patients receiving HFNC therapy after planned extubation. Of 276 patients, 50 patients (18.1%) were reintubated within 72 h of extubation. ROX index values of >8.7 at 2 h, >8.7 at 6 h, and >10.4 at 12 h after HFNC therapy were all meaningful predictors of HFNC success in extubated patients. In addition, the integrated model including the ROX index had a better predictive capability for HFNC success than the ROX index alone. In conclusion, the ROX index at 2, 6, and 12 h could be applied to extubated patients to predict HFNC success after planned extubation. To improve its predictive power, we should also consider an integrated model consisting of the ROX index, sex, body mass index, and the total duration of ventilator care.

Effects of Anger and Moral Identity on the Relationship between Supervisors' Incivility and Deviant Behavior: A Study of Public Service Officers in Republic of Korea.

Abstract: This study investigated the effects of supervisors’ incivility regarding employees’ deviant behavior, the mediating effect of anger, and the moderating role of moral identity in the relationship between incivility and deviant behavior. To test our hypotheses, we collected data from supervisor–employee dyads in South Korean military units, applying a time-lagged design, hierarchical regression, and SPSS macro. The results elicited three relevant findings. First, supervisors’ incivility was found to positively influence employees’ deviant behavior. Second, employees’ anger was confirmed to have a mediating effect between supervisors’ incivility and employees’ deviant behavior. Third, the analysis demonstrated that moral identity moderates the relationship between anger and deviant behavior, and incivility through anger has an indirect effect on deviant behavior. These findings imply that supervisors’ incivility, which is readily observed within the organization, is a harmful behavior that increases anger and deviant behavior. These findings suggest that negative leadership should be minimized and employees with high moral identity should be selected to reduce deviant behavior that harms the organization.

How Suppressed Anger Can Become an Illness: A Qualitative Systematic Review of the Experiences and Perspectives of Hwabyung Patients in Korea

Abstract: Background: In the clinical field, anger has generally been studied in terms of aggressive behavior. However, in Asians, anger suppression is more common than anger expression. Hwabyung is a culture-related anger syndrome in Korea and is known to occur due to the continued repression of anger. Investigating Hwabyung should lead to a better understanding of the multiple dimensions of anger. To explore Hwabyung patients' experiences and perspectives, a meta-aggregation approach was used to conduct a systematic review and a qualitative synthesis. Methods: A systematic search was conducted in MEDLINE/PubMed, EMBASE, Allied and Complementary Medicine Database (AMED), Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycARTICLES, and four Korean databases [Korean Medical Database (KMbase), Korean Studies Information Service System (KISS), National Digital Science Library (NDSL), and Oriental Medicine Advanced Searching Integrated System (OASIS)] in September 2020. Studies were included if they collected and analyzed qualitative data from Hwabyung patients. Qualitative research findings on the experiences and perspectives of Hwabyung patients in Korea were critically appraised and synthesized using the Joanna Briggs Institute methodology. Results: Seven eligible studies were included. The findings from those studies (i.e., theme or subtheme of qualitative research) were aggregated into categories (a group of similar findings) and synthesized findings (a group of categorized findings). Ultimately, 116 findings were aggregated into 15 categories. Finally, four synthesized findings were derived from the 15 categories: (i) anger arousal, (ii) blame, (iii) uncontrollable physical and emotional symptoms, and (iv) compromise and temporary coping. Conclusions: Patients with Hwabyung experience chronic anger through the complex cognitive processes involved in blame. Hwabyung negatively affects patients' physical, psychological, and social functions. Because Hwabyung patients feel as if they are losing control, due to emotional dysregulation and physical symptoms, professional support should be provided to facilitate their coping strategies. Further studies on Hwabyung can serve as a new model of pathological anger.

Physiological and psychological effects of forest healing focused on plant fragrance therapy for maladjusted soldiers

Abstract: Background and objective This study verified the physiological and psychological effects of plant fragrance therapy to analyze whether the therapy has a forest healing effect on maladjusted soldiers. Methods This study was conducted from March 14 to May 31, 2020 according to the Green Camp curriculum for 2 weeks per recruit class. Thus, plant fragrance therapy was implemented twice each for three recruit classes. Each session of the program was carried out for 4 hours from 1 p.m. to 5 p.m. The venue was the garden within the camp and the forest nearby. Forest healing activities using plant fragrances were led by 1 forest education specialist and 1 assistant. The effects of plant fragrance therapy for maladjusted soldiers were analzed analyzed by quantifying physiological and psychological changes through measuring brain waves and stress levels before and after the therapy. Results As a result of analyzing BRQ and SQ to determine the physiological and psychological healing effect of plant fragrance therapy, both the left and right brain showed higher BRQ and SQ after the therapy with statistical significance. This indicates that plant fragrance therapy on maladjusted soldiers helped positively stabilize their negative psychological and behavioral dispositions, and stabilization of brain waves lowered physical and mental stress and improved self-regulation and immunity. On the other hand, there was no significant difference in ATO. This is the result of analyzing the stress-coping mechanism. Troubleshooting (t = −2.702, df = 61, p = .009), emotional remission (t = −2.173, df = 61, p = .034), pursuit of help (t = −3.286), df = 61, p = .002), and wishful thinking (t = −3.714, df = 61, p < .001) showed statistically significant results. Conclusion Applying plant fragrance therapy to maladjusted soldiers positively stabilized their negative psychological and behavioral dispositions and helped their self-regulation. Thus, plant fragrance therapy has psychological and physical forest healing effect on maladjusted soldiers.

Obstructive spirometry pattern and the risk of chronic kidney disease: analysis from the community-based prospective Ansan-Ansung cohort in Korea.

Abstract: Objective There have been limited studies on the relationship between obstructive spirometry pattern and the development of chronic kidney disease (CKD). We investigated the association between obstructive spirometry pattern and incident CKD development in a large-scale prospective cohort study. Methods We reviewed the data of 7960 non-CKD adults aged 40-69 years who participated in the Ansung-Ansan cohort, a prospective community-based cohort study. Prebronchodilation results for the ratio of forced expiratory volume per 1 s (FEV1) to forced vital capacity (FVC) were used as the primary exposure. The primary outcome was incident CKD, defined as the first event of an estimated glomerular filtration rate Results Over a mean follow-up period of 11.7 years, incident CKD developed in 511 subjects (6.4%). An increase of 0.1 in FEV1/FVC was associated with a decreased risk of incident CKD (HR 0.76, 95% CI 0.68 to 0.84, p Conclusion Decreased FEV1/FVC ratio was independently associated with an increased risk of incident CKD development, particularly in people without metabolic syndrome. Future studies need to be conducted to confirm these results.

Semi-Circumferential Decompression: Total En-Bloc Ligamentum Flavectomy to Treat Lumbar Spinal Stenosis with Two-Level Degenerative Spondylolisthesis.

Abstract: Introduction Despite technical developments in decompression without fusion, many studies still assert that instability could be increased in patients with spinal stenosis and lumbar degenerative spondylolisthesis after spinal decompression surgery without fusion. Thus, this study aimed to describe and assess the clinical outcomes of the semi-circumferential decompression (SCD) technique used for microsurgical en-bloc total ligamentum flavectomy with preservation of the facet joint in treating patients who have lumbar spinal stenosis with two-level degenerative spondylolisthesis. Methods We retrospectively analyzed the clinical and radiologic outcomes of 14 patients who had spinal stenosis with two-level Meyerding grade I degenerative spondylolisthesis. We evaluated improvements in back pain and radiating pain using a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). We have also examined the occurrence of spinal instability on a radiological exam using slip percentage and slip angle. Results The mean VAS score of back pain and radiating pain has been determined to decrease significantly from 6.7 to 3.3 and from 8.6 to 2.7, respectively. Meanwhile, the ODI score significantly improved from 27.3 preoperatively to 9.8 postoperatively. Statistically significant change was not observed in the slip percentage in both upper and lower levels. Dynamic slip percentage, which is defined as the difference in the slip percentage between flexion and extension, also did not significantly change. No statistically significant change was found in the slip angle and dynamic slip angle. Conclusions SCD is a recommendable procedure that can improve clinical results. This procedure does not cause spinal instability when treating patients who have spinal stenosis with two-level degenerative spondylolisthesis.

A Study of Analysis for Noise Environment and Hearing Loss of Army Aviation Pilots

Abstract: Kyucheol Ko, Oyonghyeok Lee, Jinsook Kim, Taewon Lee, Yerim Shin, Hyesook Lee Republic of Korea Army Aviation School Combat Development Department, Nonsan, Korea Department of Speech Pathology and Audiology, Graduate School, Hallym University, Chuncheon, Korea Division of Speech Pathology and Audiology, College of Natural Sciences, Hallym University, Chuncheon, Korea Division of Mathematical Sciences, Sejong Campus, Korea University, Sejong, Korea Republic of Korea Force Aerospace Medical Center, Cheongju, Korea

Opportunities for Gravity and GNSS Surveying to Monitor Changes in the Terrestrial Water Storage in the Congo River Basin

Abstract: Monitoring terrestrial water storage (TWS) is critical for global hydrological cycles and important to sustain diverse sectors, such as agriculture, manufacturing, and other industries in many countries. Yet, we have very little knowledge of the spatiotemporal dynamics of TWS changes in the Congo River, which is the world’s second largest river in size (~3.7 million km2), and its discharge is second only to that of the Amazon River (~40,600 m3s−1). Temporal variations in the Earth’s gravitational field likely could be attributed mainly to changes in the TWS in tropical basins. Therefore, the changes in TWS can be monitored based on the Earth’s gravitational field. Although using the Global Navigational Satellite System (GNSS) to measure the gravitational field is prevalent in many regions, this approach has not been considered in the Congo Basin, which is a void. In this paper, we have outlined why it has been suggested to initiate GNSS surveying for monitoring the changes in the TWS in the Congo Basin.

System Design and Implementation of Multi-legged Spider Robots for Landmine Detection in the Demilitarized Zone

Abstract: As the Korean demilitarized zone(DMZ) has unique geological features and terrains, conventional wheel-based unmanned ground vehicles(UGVs) are hard to perform the landmine removal tasks. Compared to other types of robot platforms, multi-legged robots, which climb the inclined way and overcome the complex obstacles with lower contact area on the ground, have several advantages to perform landmine detection tasks in DMZ effectively. Thus, to exploit such benefits, in this paper, we propose the design schemes and gait methods of multi-legged spider robots. Especially, this paper presents the design and motion control of multi-legged spider robots with four and six legs. In detail, we implemented the design and motion control of multi-legged spider robots suitable for landmine detection in the DMZ by applying the gait algorithms on Arduino and Dynamixel servomotors. Our proposed algorithm and system design demonstrate that the proposed system design architecture enables operational flexibilities while walking in harsh conditions.

Dermatofibrosarcoma Protuberans in Active Duty Military Personnel: A Case Report.

Abstract: Dermatofibrosarcoma protuberans (DFSP) is an uncommon, soft tissue sarcoma with a high rate of local recurrence, low rate of distant metastasis, and infiltrative growth. We report two cases of DFSP in young active duty military personnel. Both cases underwent primary excision at the Armed Forces Capital Hospital with positive surgical margins and underwent re-excision at Samsung Medical Center. Dermatofibrosarcoma protuberans is a rare finding, and wide local excision with or without skin flap remains the procedure of choice. Awareness of DFSP in young patients is important for proper diagnosis and treatment and to achieve local control. Complete excision of the tumor with a clear surgical margin and thorough surveillance after surgery are recommended for service members to maintain their active duty status and to prevent ineffective combat conditions.