• Title/Summary/Keyword: small arms

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Fabrication and Performance Analysis of Environment Friendly Double Core Bullets for Small Arms (2중 코어 구조의 소화기용 친환경 탄자 제조 및 특성 분석)

  • Hong, Jun-Hee;Jang, Tak-Soon;Song, Chang-Bin;Kang, Dae-Wha
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.345-352
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    • 2011
  • This paper focuses on the properties analysis of 9mm bullet dual structure core to substitute current lead core by environment-friendly combination of W-Cu-Ni system high density composite materials. So the four combination samples were made of dual core with the different center of gravity location backward or forward compare to that of lead type bullet, and we experimented about the performance of 9mm bullet dual structure core. In the experimental results, the outer shape of core of four environment friendly samples on the target maintain marginally, while the current lead core bullets are completely crushed after hitting the target. The penetration depth of environment friendly samples excel seven times to lead type bullet and the three out of four samples with forward adjusted center of gravity penetrate deep as twice as ones backward. The impact tolerance of all four samples satisfies military specification, however, more firing tests are required to improve reliability of scattering distribution.

The survey study on working conditions and industrial safety & health of foreign workers (외국인근로자의 근로환경 및 안전보건실태 조사 연구)

  • Yi, Kwan-Hyung;Cho, Hm-Hak
    • Journal of the Korea Safety Management & Science
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    • v.14 no.1
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    • pp.53-63
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    • 2012
  • The purpose of this study is to grasp foreign worker's industrial safety and health state, which find out the improvement to secure the basic safety net for foreign workers. We have investigated 2,050 workers through direct interviews during the period from April 12, 2010 to May 31, 2010. And the result of analysis, foreign worker's daily average working time is 10.6 hours(40.8% workers in total work 10~12 hours), the extent of exposure to harmful and dangerous working environment is 'the position which cause pain in neck, waist, hands, shoulders, legs'(69.3%), 'repetitive hands and arms movement'(66.1%). It showed 'experience of accident damage or disease related work'(27.3%), 'never apply for industrial accident compensation' is revealed high at 73%. As a result of completing a safety health education for a year, it showed 'never educated'(40.2%), 'the institute that foreign workers have used for help and advice is the foreign worker's support center'(61.9%) Thus, hiring foreign workers in the company are small in site, the environment is too harmful and dangerous. In addition, no safety and health managers, legally blind spot located in the health and safety, because it is an urgent meet for these measures to improve.

A Study on Improvement of the Abnormal Operation of a One-shot Rifle with Bolt-action Operating System (볼트액션 작동방식 단발형 소총의 비정상 작동에 관한 개선 연구)

  • Shin, Jae Won;Jung, Chan Man;Choi, Si Young;Lee, Ho Jun;Shin, Tae Sung;Seo, Hyun Su
    • Journal of Korean Society for Quality Management
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    • v.47 no.3
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    • pp.417-424
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    • 2019
  • Purpose: In this study, the goal is to analyze this case to prevent the same accidents when using one-shot rifle. Methods: Detailed analysis of damaged parts must first be made in order to determine the cause of the abnormal explosion. The cause of abnormal operation can be determined by analyzing the information of damaged components and the firing mechanism of the weapon step by step. Also we can refer to a statement of shooter, witness and accident scene situation. Based on this theory, cause of abnormal firing can be narrow down. Results: Fracture of pin for fixing firing and latch is cause of abnormal operation of firing. Conclusion: It is deemed that periodic inspection and fundamental improvement of the structure are required to prevent the same accident as this.

Comparative Analysis of the Complete Genomes of Three Ficus L. (Moraceae) Species and Its Implication

  • Kim, Tae-Hee;Jung, Joonhyung;Kim, Joo-Hwan
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.41-41
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    • 2019
  • The genus Ficus L., containing approximately 850 species, is by far the largest genus in the Moraceae. They are mainly distributed worldwide, mainly in tropical countries. In South Korea, there are three native Ficus (including F. erecta Thunb, F. sarmentosa var. nipponica (Franch. & Sav.) Corner, and F. thunbergii Maxim.). Among them, F. erecta is effectively natural resources for the improvement of senile cognitive impairment. However, the chloroplast (cp) genome sequences and information of F. erecta have not been addressed. Therefore, in this study, we provide the complete cp genome of F. erecta and its allied species using next-generation sequencing technology. The chloroplast of Ficus species has typical structure which includes large and small single copy regions and a pair of inverted repeats (IRs). The sizes of cp genomes range from 160,276 bp to 160,603 bp. To determine the phylogenetic positions of these species, we conducted a maximum likelihood analysis using common protein-coding genes in chloroplast sequences. Also, we describe a newly developed single nucleotide polymorphism (SNP) markers using multiplex PCR to identify F. erecta based on amplification-refractory mutation system (ARMS) technique. We analyzed matK, atpB of the chloroplast genes and ITS from F. erecta and three related taxa, F. carica, F. sarmentosa var. nipponica and F. thunbergii. It provides useful information for molecular identification between F. erecta and related Korean native species.

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Simplified Formula for Predicting the Ballistic Limit Velocity of High Strength Shipbuilding Steel Plates Based on Experimental Data (함정용 고장력 판재의 방호한계속도 추정을 위한 간이 실험식)

  • Moon, Seok-Jun;Kim, Won;Song, Jinseop;Choi, Jong-Min
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.5
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    • pp.322-329
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    • 2021
  • Naval ships are designed to have a variety of active and passive systems to defend against enemy threats. One of the passive defense systems is to protect crew members and core equipment against the threat by using the outer plate of the equipment. This study was intended to deal with design methods against small arms ammunition and fragments. The Korea Institute of Machinery and Materials has measured the ballistic limit velocity of two types of high-tensile plate materials (AH36 and EH36) widely used in ships and offshore structures through tests in cooperation with various related organizations, and the result data is continuously accumulated. Based on the accumulated test results and data, such as mil test certificates of plate materials, it is intended to estimate the protection limit speed of high-tensile plates and to develop a simple calculating formula that can be used in the early design stage.

One new species and one new record of lymantriine moths (Lepidoptera: Erebidae: Lymantriinae) in Korea

  • Kim, Nang-Hee;Choi, Sei-Woong;Kim, Sung-Soo
    • Journal of Species Research
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    • v.8 no.3
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    • pp.288-293
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    • 2019
  • Herein, we report a new record of Arna bipunctapex (Hampson) and a new species, Euproctis fulvatus sp. nov. in Korea; both are Lymantriine moths. Arna bipunctapex is distinguished by a relatively large wingspan with two black dots and a small dot between these black dots in the apical region of a yellowish forewing. The male genitalia of A. bipunctapex can be distinguished by the lack of a process on the sacculus of valva while the female genitalia can be distinguished by an antrum that is basally flat with two lateral digitate arms. Euproctis fulvatus is distinguished by yellowish wings with a medially curved central fascia of the forewing. The male genitalia can be distinguished by the bifid, digitate uncus and the simple, square-shaped valva with a distal strong invaginated margin. The female genitalia can be distinguished by the long, medially twisted, ductus dursae with simple antrum posteriorly strongly sclerotized and ovate corpus bursae without signum. Larvae of E. fulvatus are distinguished by a black head with a pair of long, black, lateral tufts, dorsum with 10-11 white intersegmental dots and bright red setal warts on T2-A8, and bright red glands on A6 and A7.

Exploring the Effects of the Virtual Human with Physicality on Co-presence and Emotional Response

  • Shin, Kwang-Seong;Jo, Dongsik
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.1
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    • pp.67-71
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    • 2019
  • With continued technology innovation in the fields of computer graphics (CG) and virtual reality (VR), digital animated avatars (or virtual humans) are evolving into ones that are more interactive at a suitable location such as museum, airport, and shopping mall. Specially, the form of the avatar (or the virtual human) realistically need to be expressed in a way that matches the users' physical space. In recent many researches, the form of virtual human has been expressed as mixed-reality human (MRH)-the virtual human combines with the physicality as the real part. In this paper, we propose to carry out a study comparing various MRH on co-presence and emotional response in two-typed virtual humans depending on how many actual parts are included: (1) (Level 1) small parts in the virtual human combined virtual components (e.g., the head only) and (2) (Level 2) large parts in the virtual human with the physicality as the real part such as head, arms, and upper body). We report on the implemented results of our virtual humans and experimental results on co-presence and emotional response.

Repair of tendon injury in Taekwondo by nanobiotics

  • Dilong An;Shun Jiang;Tongtong Cai;Wei Tian
    • Advances in nano research
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    • v.14 no.6
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    • pp.591-602
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    • 2023
  • In the present study, capability of nanobiotics in repairing tendon injuries commonly occur in Taekwondo sport is investigated and some approaches are proposed. In this regard, a brief review on the types and application of nanobiotics is presented. Their capabilities and limitation are discussed. Next, different type of tendon injuries in Taekwondo athletes are discussed along with their treatment approaches. Based on the presented data, a nano-scale feasible robot model carrying nanobiotics is proposed for repairing tendons. Finite element simulations is also conducted to show the effectiveness of the repairing process using nanorobots equipped with nanobiotics. This repairing procedure is a combination of mechanical and chemical treatments. The results indicated that using nanobiotics on nanorobots arms in the repair of tendon injuries has many benefits. First, drug delivery is directly injected to the target section. Second, Due to the nanorobots small sizes more acute treatment is possible. Finally, since the control of the nanorobots are assisted with computers, the possibility of human error reduces significantly. The proposed method of the present study could be utilized by other scientists and technological industry in developing final nanorobots with nanobiotics carrying capacity.

Reconstruction of the Soft Tissue Defect on Anteromedial Surface of the Leg Using Medial Hemisoleus Flap

  • Park, Il-Jung;Sur, Yoo-Joon;You, Sung-Lim
    • Archives of Reconstructive Microsurgery
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    • v.23 no.2
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    • pp.76-81
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    • 2014
  • Purpose: Anteromedial surface of the leg is susceptible to trauma, which frequently induces soft tissue defect. When the size of a soft tissue defect is small to moderate, a local muscle flap is an easy and reliable alternative to a free flap. The authors performed medial hemisoleus flaps for reconstruction of soft tissue defects on the anteromedial surface of legs. The aim of this study was to evaluate clinical outcomes and effectiveness of the medial hemisoleus flap. Materials and Methods: Twelve patients underwent the medial hemisoleus flap for reconstruction of a soft tissue defect on the anteromedial surface of the leg from February 2009 to December 2013. There were eight males and four females with a mean age of 47.8 years (15 to 69 years). The mean size of defects was $4.7{\times}4.2cm$ ($2{\times}2$ to $9{\times}6cm$). Flap survival and postoperative complications were evaluated. Results: Mean follow-up period was 39.6 months (7 to 64 months) and all flaps survived. There were two cases of negligible necrosis of distal margin of the flap, which were healed after debridement. All patients were capable of full weight bearing ambulation at the last follow-up. Conclusion: The medial hemisoleus flap is a simple, reliable procedure for treatment of a small to moderate sized soft tissue defect on the anteromedial surface of the leg.

Cisplatin-Based Therapy for the Treatment of Elderly Patients with Non-Small-Cell Lung Cancer: a Retrospective Analysis of a Single Institution

  • Inal, Ali;Kaplan, M. Ali;Kucukoner, Mehmet;Urakcl, Zuhat;Karakus, Abdullah;Islkdogan, Abdurrahman
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.1837-1840
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    • 2012
  • Background: In spite of the fact that platinum-based doublets are considered the standard therapy for patients with advanced non-small-cell lung cancer (NSCLC), no elderly-specific platinum based prospective phase III regimen has been explored. The aim of this retrospective singlecenter study was to evaluate the efficacy and side effects of cisplatin-based therapy specifically for the elderly. Methods: Patients receiving platinum-based treatment were divided into three groups. In the first group (GC), Gemcitabine was administrated at 1000 $mg/m^2$ on days 1, 8 and cisplatin was added at 75 $mg/m^2$ on day 1. In the second group (DC), 75 $mg/m^2$ docetaxel and cisplatin were administered on day 1. The third group (PC) received 175 mg of paclitaxel and 75 mg of cisplatin on day 1. These treatments were repeated every three weeks. Result: GC arm had 36, the DC arm 42 and the PC arm 29 patients. Grade III-IV thrombocytopenia was higher in the GC arm (21.2% received GC, 2.8% received DC, and 3.8% received PC), while sensory neuropathy was lower in patients with GC arm (3.0%, 22.2%, and 23.1% received GC, DC and PC, respectively). There were no statistically significant difference in the response rates among the three groups (p>0.05). The median Progression-free survival (PFS) was 5.0 months and the median Overall survival (OS) in each group was 7.1, 7.4 and 7.1 months, respectively (p>0.05). Conclusion: The response rate, median PFS and OS were similar among the three treatment arms. Grade III-IV thrombocytopenia was higher in the GC arm, while the GC regimen was more favorable than the other cisplatin-based treatmetns with regard to sensory neuropathy.