• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
• /
• pp.418-422
• /
• 2017

공개된 자료들을 바탕으로 NASA의 표준 착화기 NSI-1,2,3의 간략한 성능규격 비교와 함께 NSI에 연결되는 전기 커넥터의 규격을 비교하였다. NSI-1,2에 연결되는 커넥터의 규격은 MSFC-40M38298과 MIL-DTL-26482, series1이며, NSI-3에 연결되는 커넥터의 규격은 MIL-DTL-38999, series3이다. 전체적인 내환경 성능은 낮음에서 높음 순서로 MIL-DTL-26482, series1/MSFC-40M38298/MIL-DTL-38999, series3 이다. 특히, 고충격, 고진동 환경에서 착화기를 사용하여야 한다면 NSI-3의 커넥터 규격인 MIL-DTL-38999, series3의 커넥터를 사용하는 것이 적절할 것이다.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제15권1호
• /
• pp.19-26
• /
• 2015

The amended law of railway safety in Korea has recently come into effect in order to strengthen the railway safety management system. The new law, which took effect March 1, 2014, will implement stricter oversight of railway companies. As a result, a company that manufactures railroad system or components for domestic use must obtain an approval in accordance with the technical specifications of manufacturer approval. Although Korea had established the legal system in enforcing railway safety, the government wants the companies continue to develop the more improved safety systems until they gain competitive edge on the world class railway manufacturers. This paper presents an in-depth analysis of the technical specifications for manufacturer approval in International Railway Industry Standard (IRIS), which is the global standard. This paper also proposes measures and guidelines that would help Korean manufacturers those who want further develop their safety management systems, as a prerequisite for them to obtain the manufacturer approval.

• 한국컴퓨터정보학회논문지
• /
• 제27권9호
• /
• pp.113-120
• /
• 2022

본 논문에서는 5G 네트워크에서 Null 보안 알고리즘 (Null Security Algorithm)을 악용한 IP 스푸핑 공격 (IP Spoofing Attack)의 실현 가능성을 3GPP 표준 규격에 근거하여 분석한다. 3GPP 표준 규격에 따르면, 초기 Registration Request 메시지는 암호화 및 무결성 보호를 받지 못한다. IP 스푸핑 공격은 피해자 UE (User Equipment)의 초기 Registration Request 메시지의 내용을 악의적인 gNB (next generation Node B)가 수정한 뒤 AMF (Access and Mobility Management Function)에게 전송할 수 있다는 취약점을 활용하는 공격이다. 공격이 성공하면, 피해자 UE는 5G 네트워크에서 연결이 끊어지고 악의적인 UE가 인터넷 서비스를 사용하지만 5G 사업자는 피해자 UE에게 요금을 청구한다. 본 논문에서는 IP 스푸핑 공격을 구성하는 각각의 시그널링 메시지가 3GPP Rel-17 표준 규격에서 허용되는 것인지 여부를 분석함으로써 IP 스푸핑 공격의 실현 가능성을 분석한다. 분석 결과, 3GPP Rel-17 표준 규격에 따라 구현된 5G 시스템에서 IP 스푸핑 공격은 실현 불가능한 공격으로 판단된다.

• 대한인간공학회지
• /
• 제13권2호
• /
• pp.13-24
• /
• 1994

The objectives of this study are twofold : (1) to investigate musculoskeletal discomfort for sedentary workers in offices ane (2) to revise the Korean Standard for the design of office chairs in order to reduce or eliminate the physical discomfort or the office workers. Two hundred seventy-one office workers from nineteen different companies companies were selected to evaluate the musculoskeletal discomfort and indibidual features of chair design. A statistical analysis of the survey rebealed that the office currently being used had two major deficiencies such as insufficient adjustability and inappropriate design specifications in ergonomic sense. A stepwise regression analysis showed that the deficiencies on the musculoskeletal discomfort of the workers. Based on the ergonomic design pronciples, was debeloped to revise the Korean Standard for the design specifications of office chairs. An application of the methodology was made amend the design specifications of the four factors such as seat pan height, seat pan width, and seat pan inclunation. Their effects were evident in the musculoskeletal discomfort of the workers.

• 한국구조물진단유지관리공학회 논문집
• /
• 제13권1호통권53호
• /
• pp.145-151
• /
• 2009

교량 계측시스템의 계측항목 중 거더 중앙부 처짐은 교량 상부구조의 대표적인 거동 특성이며, 중요한 상태평가 항목이다. 교량 계측시스템에서 교량 경간 중앙부 처짐에 대한 관리기준치를 설정하는 여러 가지 방법 중 도로교 설계기준의 처짐 제한치를 적용하는 경우도 있다. 그러나 도로교설계기준의 처짐 제한규정은 안전성 측면보다는 사용성 측면에서 검토되어 실제 교량에서 발생할 수 있는 위험상황에 대하여 어느 정도 안전을 보장하는지 판단하기 어렵다. 본 연구는 현재 교량 설계시 경간 중앙부 처짐의 사용성 검토 기준이고, 일부 교량 상시계측시스템의 경간 중앙부 관리기준치로 적용되고 있는 도로교설계기준의 처짐 제한치가 포함하고 있는 파괴(항복)에 대한 실질적인 안전율을 추정해 보고자 실내구조실험을 통하여 일반 철근콘크리트 거더의 안전율을 추정하였다.

• 한국산학기술학회논문지
• /
• 제12권4호
• /
• pp.1597-1602
• /
• 2011

150개 군수업체를 대상으로 실시한 설문조사를 통해, 국방규격 및 민간표준 규격에 대한 활용 실태와 국방규격의 KS 부합화에 따른 경제적 효과 분석을 수행하였다. 대부분의 업체에서는 기업에서 활용하는 국방규격이나 인용 규격의 최신 변경사항에 대한 충분한 정보를 얻지 못하는 것으로 나타났다. 특히, 국방규격은 정보에 대한 접근 제한성으로 인해 최신 동향을 파악하기가 어렵다는 응답이 많았는데, 이는 국방규격이나 도면 검색 프로그램에 대한 활용을 통해 다소나마 해결될 것으로 판단된다. 국방규격의 KS 부합화 사업에 대해서는 많은 업체에서 품질향상, 연구 개발기간 단축, 생산성 증대, 표준 구매 및 교육 비용 절감 등과 관련하여 군수품 원가 절감에 다각적으로 기여할 것으로 예상하는 것으로 나타났다.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2021년도 가을 학술논문 발표대회
• /
• pp.200-201
• /
• 2021

According to the dispute cases filed for claiming the collective defect repair fees, inter-layer concrete joints turned out to be the most frequently disputed item. For this reason, this study selects the inter-layer concrete joints to further analyze the primary causes and details of each dispute case. From the results of this study, three primary causes of the disputes are found, which are 1) the absence of standard specifications for construction quality control and management after construction; 2) the absence of established standards for repair when construction defects are found. In order to prevent construction defects in inter-layer concrete joints, this study provides three suggestions including 1) the current standard specifications for inter-layer concrete joints should be further specified by the Ministry of Land, Infrastructure and Transport; 2) a construction defect should be judged according to the compliance to the standard specifications; and 3) a clear and institutional protocol needs to be established for defect repair in cases that new public apartment houses have been judged to have defects.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권8호
• /
• pp.1158-1164
• /
• 2003

In two feeding experiments male and mixed-sex broiler chicks were offered diets based on sorghum and a wheatsorghum blend with two tiers of nutrient specifications, without and with microbial phytase (600 and 800 FTU/kg), from 7-25 and 1-42 days post-hatch, respectively. The nutrient specifications for protein, amino acids, energy density and phosphorus (P) of standard diets were reduced to formulate the modified diets on a least-cost basis. Calculated differences in nutrient specifications between standard and modified diets ranged from 14.3 to 17.1 g/kg crude protein, 0.24 to 0.40 MJ/kg apparent metabolisable energy (AME) and 1.06 to 1.20 g/kg available P. In both experiments, reduced nutrient specifications had a negative impact on growth rates and feed efficiency and phytase supplementation had a positive influence on growth performance and protein efficiency ratios (PER). Phytase addition to the less expensive, modified diets either partially or entirely compensated for reduced growth performance and, consequently, feed costs per kg of live weight gain were reduced. In Experiment 1, phytase increased (p<0.001) nitrogen-corrected AME (AMEn) from 15.39 to 15.89 MJ/kg dry matter. For nitrogen (N) retention there was an interaction (p<0.05) between diet type and phytase as the effects of phytase on N retention were more pronounced in the modified diets, with an increase from 0.512 to 0.561. These results demonstrate the positive effects of phytase on protein and energy utilisation, in addition to its established liberation of phytate-bound P and illustrate the feasibility of assigning nutrient replacement values to the feed enzyme for consideration in least-cost ration formulations. Further work is, however, required to define the most appropriate reductions in nutrient specifications in association with phytase supplementation.

• 품질경영학회지
• /
• 제46권3호
• /
• pp.497-508
• /
• 2018

Purpose: The purpose of this study is to research the revision efficiency of the referenced specifications/standards for raw and subsidiary materials in the field of national defense. Methods: Firstly, it was carried out to investigate the all of the Korean military drawings and establish the database for specifications/standards referenced in the field of national defense. Secondly, it was reviewed the validity of referenced specifications/standards of raw and subsidiary materials. Finally, proposal documents were made for invalid referenced specifications/standards of raw and subsidiary materials in order to suggest alternative specifications/standards. Results: All of the specifications/standards referenced in the Korean military drawings were 11,924 kinds and raw and subsidiary specifications/standards were 2,711 kinds. The proposal documents for revision of invalid referenced specifications/standards were suggested and approved by the military procurement standardization committee of DAPA (Defense Acquisition Program Administration). Therefore, the revision process of 472 kinds of referenced specifications/standards and 160,177 papers of the Korean military drawings were finished. Conclusion: Based on the results of this investigation, it could be significantly reduce to administrative costs and efforts through revision of referenced specifications/standards instead of conventional engineering change.

• 한국CDE학회논문집
• /
• 제17권2호
• /
• pp.140-148
• /
• 2012

This study aims to provide power monitoring system for super tall buildings with 3D BIM (Building Information Modeling) technology. In order to realize this subject, standard specifications for BIM objects and attributes were studied through analyzing processes and elements of electrical utilities for power management systems applied for super tall buildings. These standard BIM specifications could be used by designers, contractors and facility operators, and thus could be helpful to realize BIM information sharing between multiple disciplines and construction phases. And further study has been suggested to develop standard specification and applications from this study.