• Title/Summary/Keyword: Department of Military Studies

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Acoustic emission localization in concrete using a wireless air-coupled monitoring system

  • Yunshan Bai;Yuanxue Liu;Guangjian Gao;Shuang Su
    • Smart Structures and Systems
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    • v.32 no.4
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    • pp.195-205
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    • 2023
  • The contact acoustic emission (AE) monitoring system is time-consuming and costly for monitoring concrete structures in large scope, in addition, the great difference in acoustic impedance between air and concrete makes the detection process inconvenient. In this work, we broaden the conventional AE source localization method for concrete to the non-contact (air-coupled) micro-electromechanical system (MEMS) microphones array, which collects the energy-rich leaky Rayleigh waves, instead of the relatively weak P-wave. Finite element method was used for the numerical simulations, it is shown that the propagation velocity of leaky Rayleigh waves traveling along the air-concrete interface agrees with the corresponding theoretical properties of Lamb wave modes in an infinite concrete slab. This structures the basis for implementing a non-contact AE source location approach. Based on the experience gained from numerical studies, experimental studies on the proposed air-coupled AE source location in concrete slabs are carried out. Finally, it is shown that the locating map of AE source can be determined using the proposed system, and the accuracy is sufficient for most field monitoring applications on large plate-like concrete structures, such as tunnel lining and bridge deck.

A parasitological study on the possible toilet ruins of the Japanese colonial period in Korea

  • Jieun Kim;Min Seo;Hisashi Fujita;Jong Yil Chai;Jin Woo Park;Jun Won Jang;In Soo Jang;Dong Hoon Shin
    • Parasites, Hosts and Diseases
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    • v.61 no.2
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    • pp.198-201
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    • 2023
  • In the past decade, experts have conducted parasitological research on archaeological specimens in Korea to collect historical parasite infection data. In these studies, parasitologists successfully described the infection pattern of each parasite species in history. However, in the first half of the 20th century, archaeoparasitological reports have been scant. In 2021, we conducted a parasitological examination of a toilet-like structure that emerged in the early 20th century. This structure was built by stacking 2 wooden barrels; and in the study samples, we found ancient Trichuris trichiura, Ascaris lumbricoides (unfertilized), and Taenia spp. eggs and therefore proposed a higher possibility that the barrels could have been used as a toilet at the time. To understand how the antihelminthic campaign since the 1960s helped reduce parasite infection rates in Korea, more research should focus on early-20th-century toilet ruins.

Genetic Association between ERCC5 rs17655 Polymorphism and Colorectal Cancer Risk: Evidence Based on a Meta-analysis

  • Zeng, Yong;Wei, Li;Wang, Ya-Jie;Liu, Chuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.13
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    • pp.5565-5571
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    • 2015
  • Background: Previous studies evaluating the association between the excision repair cross complementing group 5 (ERCC5) gene rs17655 polymorphism and colorectal cancer susceptibility generated controversial results. To generate large-scale evidence on whether the ERCC5 rs17655 polymorphism might indeed be associated with colorectal cancer susceptibility, the present meta-analysis was performed. Materials and Methods: Data were collected from PubMed, Embase and Web of Science, with the last report up to Apr 03, 2015. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of any association. Results: A total of nine studies including 5,102 cases and 6,326 controls based on the search criteria were included and significant associations were found between ERCC5 rs17655 polymorphism CG vs GG overall (OR = 1.29, 95% CI =1.18~1.40) and in the dominant model (OR=1.23, 95% CI =1.13~1.33). On subgroup analysis by ethnicity and source of controls, the ERCC5 rs17655 polymorphism was found to correlate with the pathogenesis of colorectal cancer among Asians and Caucasians and with hospital-based populations. Conclusions: This meta-analysis suggests that the ERCC5 rs17655 polymorphism might contribute to genetic susceptibility to colorectal cancer.

Epidemiology and Incidence of Orthopedic Fractures in the Military of the Republic of Korea

  • An, Sung-Jin;Lee, Sang Hyun;Moon, Gi-Ho
    • Journal of Trauma and Injury
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    • v.34 no.1
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    • pp.50-56
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    • 2021
  • Purpose: Fractures are common in the military population, but limited studies have investigated the incidence of fractures among Korean military personnel. Hence, this study aimed to clarify this issue. Methods: Eligible subjects were patients who had sustained a fracture and were registered in the N-DEMIS (the medical records system of participating hospitals) from June 2017 to May 2019. Fractures were categorized according to the fracture site, patients' age, sex, and type of duty. Results: In total, 23,687 patients with 23,981 fractures were included. There were 216 patients with multiple fractures, of whom 156 had fractures at two sites, 42 had fractures at three sites, and 18 had fractures at four sites. Of the 23,687 patients, 23,340 were men and 347 were women. The incidence of fractures in men and women was 12.96 per 1,000 person-years and 0.19 per 1,000 person-years, respectively. In terms of the broad location of fractures, the percentage of fractures was the highest in the hand, followed by the foot and lower leg. When the location of fractures was analyzed more specifically, the percentage of fractures was the highest in the phalanx (thumb and fingers), followed by the ankle and metacarpal bones. Conclusions: Hand, foot, ankle, and wrist fractures were the most commonly encountered fractures in the Korean military population. To prevent the loss of combat power due to non-battle-related injuries, thorough preparation is necessary, including protective equipment and preliminary training for areas with a high frequency of fracture occurrence.

Epidural Lysis of Adhesions

  • Lee, Frank;Jamison, David E.;Hurley, Robert W.;Cohen, Steven P.
    • The Korean Journal of Pain
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    • v.27 no.1
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    • pp.3-15
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    • 2014
  • As our population ages and the rate of spine surgery continues to rise, the use epidural lysis of adhesions (LOA) has emerged as a popular treatment to treat spinal stenosis and failed back surgery syndrome. There is moderate evidence that percutaneous LOA is more effective than conventional ESI for both failed back surgery syndrome, spinal stenosis, and lumbar radiculopathy. For cervical HNP, cervical stenosis and mechanical pain not associated with nerve root involvement, the evidence is anecdotal. The benefits of LOA stem from a combination of factors to include the high volumes administered and the use of hypertonic saline. Hyaluronidase has been shown in most, but not all studies to improve treatment outcomes. Although infrequent, complications are more likely to occur after epidural LOA than after conventional epidural steroid injections.

The Psychopathological Influence of Adolescent Idiopathic Scoliosis in Korean Male : An Analysis of Multiphasic Personal Inventory Test Results

  • Oh, Chang Hyun;Shim, Yu Shik;Yoon, Seung Hwan;Park, Hyeong-Chun;Park, Chong Oon;Lee, Myoung Seok
    • Journal of Korean Neurosurgical Society
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    • v.53 no.1
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    • pp.13-18
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    • 2013
  • Objective : There are few published studies which have documented psychopathological abnormalities in patients with of adolescent idiopathic scoliosis (AIS) The aim of this study was to evaluate the psychopathological influence of AIS in Korean 19-year-old males. Methods : The authors compared the Korean military multiphasic personal inventory (KMPI) military profiles of 105 AIS cases (more than 10 degrees of Cobb's angle without surgical treatment) with the KMPI profiles of 108 normal controls. The AIS group was split depending on Cobb's angle to further evaluate this relation by the severity of AIS. Results : A significantly decreased result on the faking-good response scale and an significantly increased result on the faking-bad response were observed in the AIS group compared to the control (p<0.012). The neurosis scale results, including anxiety, depression and somatization symptoms, were significantly increased in the AIS group compared to the control (p<0.010). The severity level of personality disorder and schizophrenia were also significantly increased in the AIS group (p<0.010). Differences in KMPI scale scores were not related to the severity of AIS. Conclusion : Young males with AIS tend to have abnormal results on the multiphasic personal inventory test compared to normal volunteers, suggesting that AIS may be related to psychopathology in the young male group in Korea. Although these psychopathology in AIS were differently observed compared to normal controls, but not interfered with military life. Clinicians are recommended to pay attention the psychopathological traits of patients with AIS.

Study on Modeling and Simulation for Fire Localization Using Bayesian Estimation (화원 위치 추정을 위한 베이시안 추정 기반의 모델링 및 시뮬레이션 연구)

  • Kim, Taewan;Kim, Soo Chan;Kim, Jong-Hwan
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.6
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    • pp.424-430
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    • 2021
  • Fire localization is a key mission that must be preceded for an autonomous fire suppression system. Although studies using a variety of sensors for the localization are actively being conducted, the fire localization is still unfinished due to the high cost and low performance. This paper presents the modeling and simulation of the fire localization estimation using Bayesian estimation to determine the probabilistic location of the fire. To minimize the risk of fire accidents as well as the time and cost of preparing and executing live fire tests, a 40m × 40m-virtual space is created, where two ultraviolet sensors are simulated to rotate horizontally to collect ultraviolet signals. In addition, Bayesian estimation is executed to compute the probability of the fire location by considering both sensor errors and uncertainty under fire environments. For the validation of the proposed method, sixteen fires were simulated in different locations and evaluated by calculating the difference in distance between simulated and estimated fire locations. As a result, the proposed method demonstrates reliable outputs, showing that the error distribution tendency widens as the radial distance between the sensor and the fire increases.

The CHEK2 I157T Variant and Colorectal Cancer Susceptibility: A Systematic Review and Meta-analysis

  • Liu, Chuan;Wang, Qing-Shui;Wang, Ya-Jie
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.2051-2055
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    • 2012
  • Background: The cell cycle checkpoint kinase 2 (CHEK2) gene I157T variant may be associated with an increased risk of colorectal cancer, but it is unclear whether the evidence is sufficient to recommend testing for the mutation in clinical practice. Materials and Methods: We systematically searched PubMed, EMBASES, Elsevier and Springer for relevant articles before Apr 2012. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using a fixed-effects or random-effects models with Review Manager 5.0 software. Results: A total of seven studies including 4,029 cases and 13,844 controls based on the search criteria were included for analysis. A significant association of the CHEK2 I157T C variant with unselected CRC was found (OR = 1.61, 95% CI = 1.40-1.87, P < 0.001). We also found a significant association with sporadic CRC (OR = 1.48, 95% CI = 1.23-1.77, P < 0.001) and separately with familial CRC (OR = 1.97, 95% CI = 1.41-2.74, P < 0.001). Conclusion: This meta-analysis demonstrates that the CHEK2 I157T variant may be another important CRC-predisposing gene, which increases CRC risk, especially in familial CRC.

Study on Delivery of Military Drones and Transport UGVs with Time Constraints Using Hybrid Genetic Algorithms (하이브리드 유전 알고리즘을 이용한 시간제약이 있는 군수 드론 및 수송 UGV 혼합배송 문제 연구)

  • Lee, Jeonghun;Kim, Suhwan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.25 no.4
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    • pp.425-433
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    • 2022
  • This paper studies the method of delivering munitions using both drones and UGVs that are developing along with the 4th Industrial Revolution. While drones are more mobile than UGVs, their loading capacity is small, and UGVs have relatively less mobility than drones, but their loading capacity is better. Therefore, by simultaneously operating these two delivery means, each other's shortcomings may be compensated. In addition, on actual battlefields, time constraints are an important factor in delivering munitions. Therefore, assuming an actual battlefield environment with a time limit, we establish delivery routes that minimize delivery time by operating both drones and UGVs with different capacities and speeds. If the delivery is not completed within the time limit, penalties are imposed. We devised the hybrid genetic algorithm to find solutions to the proposed model, and as results of the experiment, we showed the algorithm we presented solved the actual size problems in a short time.

Use of Complementary and Alternative Medicine in Patients with Gynecologic Cancer: a Systematic Review

  • Akpunar, Dercan;Bebis, Hatice;Yavan, Tulay
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7847-7852
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    • 2015
  • Purpose: Research carried out with gynecologic cancer patients using CAM was reviewed to provide a source for discussing which CAM method is used for which purpose, patients' perceptions on the effects/side effects occurred during/after using CAM and their sources of information regarding CAM. Materials and Methods: This literature review was carried out for the period between January 2000 and March 2015 using Scopus, Dynamed, Med-Line, Science Dırect, Ulakbim, Research Starters, Ebscohost, Cinahl Complete, Academic Onefile, Directory of Open Access Journals, BMJ Online Journals (2007-2009), Ovid, Oxford Journal, Proquest Hospital Collection, Springer-Kluwer Link, Taylor & Francis, Up To Date, Web Of Science (Citation Index), Wiley Cochrane-Evidence Base, Wiley Online Library, and Pub-Med search databases with "complementary and alternative medicine, gynecologic cancer" as keywords. After searching through these results, a total of 12 full length papers in English were included. Results: CAM use in gynecologic cancer patients was discussed in 8 studies and CAM use in breast and gynecologic cancer patients in 4. It was determined that the frequency of CAM use varies between 40.3% and 94.7%. As the CAM method, herbal medicines, vitamins/minerals were used most frequently in 8 of the studies. When the reasons why gynecologic cancer patients use CAM are examined, it is determined that they generally use to strengthen the immune system, reduce the side effects of cancer treatment and for physical and psychological relaxation. In this review, most of the gynecologic cancer patients perceived use of CAM as beneficial. Conclusions: In order that the patients obtain adequate reliable information about CAM and avoid practices which may harm the efficiency of medical treatment, it is recommended that "Healthcare Professionals" develop a common language.