• 제목/요약/키워드: purge system

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Removal of residual VOCs in a collection chamber using decompression for analysis of large volatile sample

  • Lee, In-Ho;Byun, Chang Kyu;Eum, Chul Hun;Kim, Taewook;Lee, Sam-Keun
    • Analytical Science and Technology
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    • v.34 no.1
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    • pp.23-35
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    • 2021
  • In order to measure the volatile organic compounds (VOCs) of a sample which is too large to use commercially available chamber, a stainless steel vacuum chamber (VC) (with an internal diameter of 205 mm and a height of 50 mm) was manufactured and the temperature of the chamber was controlled using an oven. After concentrating the volatiles of the sample in the chamber by helium gas, it was made possible to remove residual volatile substances present in the chamber under reduced pressure ((2 ± 1) × 10-2 mmHg). The chamber was connected to a purge & trap (P&T) using a 6 port valve to concentrate the VOCs, which were analyzed by gas chromatography-mass spectrometry (GC-MS) after thermal desorption (VC-P&T-GC-MS). Using toluene, the toluene recovery rate of this device was 85 ± 2 %, reproducibility was 5 ± 2 %, and the detection limit was 0.01 ng L-1. The method of removing VOCs remaining in the chamber with helium and the method of removing those with reduced pressure was compared using Korean drinking water regulation (KDWR) VOC Mix A (5 μL of 100 ㎍ mL-1) and butylated hydroxytoluene (BHT, 2 μL of 500 ㎍ mL-1). In case of using helium, which requires a large amount of gas and time, reduced pressure ((2 ± 1) × 10-2 mmHg) only during the GC-MS running time, could remove VOCs and BHT to less than 0.1 % of the original injection concentration. As a result of analyzing volatile substances using VC-P&T-GC-MS of six types of cell phone case, BHT was detected in four types and quantitatively analyzed. Maintaining the chamber at reduced pressure during the GC-MS analysis time eliminated memory effect and did not affect the next sample analysis. The volatile substances in a cell phone case were also analyzed by dynamic headspace (HT3) and GC-MS, and the results of the analysis were compared with those of VC-P&T-GC-MS. Considering the chamber volume and sample weight, the VC-P&T configuration was able to collect volatile substances more efficiently than the HT3. The VC-P&T-GC-MS system is believed to be useful for VOCs measurement of inhomogeneous large sample or devices used inside clean rooms.

The Soviet Archival System from the Russian Revolution to the 1930's (러시아혁명 이후부터 1930년대까지의 소련의 기록관리제도)

  • Cho, Ho-Youn
    • Journal of Korean Society of Archives and Records Management
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    • v.4 no.2
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    • pp.23-39
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    • 2004
  • The Bolshevik Revolution of 1917 resulted not only in the establishment of the Socialist regime, but also in the critical changes in the Russian archival system. The Soviet government issued "Decree On the Reorganization and Centralization of Archival Affairs in the Russian Socialist Federated Soviet Republic", which prepared the ground for the archival administration in USSR. After having been revised and supplemented in the 1920's, the decree, signed by V. I. Lenin, was changed into "The Decree on the Archival Administration of Russian Soviet Federated Socialist Republic", by which the Bolshevik government was able not only to develop the conception of the State Archival Fond with the Single Archival Fond, but also to enlarge the archival collection. Besides, it was remarkable that the archival decree of 1929 provided the justification for actual developments of the archival institution. And from the practical point of view, the decree improved the archival affairs by means of the defining of the conservation period. It was at the beginning of the Stalin's period that the decree of 1929 was issued. Therefore, it may be said that the decree was one of the proofs as well as the agricultural collectivization and the industrialization that Stalin gained the overall control of the Soviet government. It was confirmed when the Second Conference of Soviet Archivists was held from 25 May to 1 June in 1929. After this meeting, M. N. Pokrovskii, who was the director of the Archival Administration in the course of the 1920's, lost the influence over the Soviet archival organizations, which meant that the autonomy of the Soviet archivists was reduced in a great degree. The Central Archival Administration of the Bolshevik regime experienced the analogous changes. It was changed into the Central Archival Agent in 1929 when the Stalinist system became strengthened. At the same time, it was significant that the Central Archival Administration of USSR was established. However, the Soviet archival affairs became under the direct control of the N. K. V. D. in the period of the Great Purge.

The Changing Aspects of North Korea's Terror Crimes and Countermeasures : Focused on Power Conflict of High Ranking Officials after Kim Jong-IL Era (북한 테러범죄의 변화양상에 따른 대응방안 -김정일 정권 이후 고위층 권력 갈등을 중심으로)

  • Byoun, Chan-Ho;Kim, Eun-Jung
    • Korean Security Journal
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    • no.39
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    • pp.185-215
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    • 2014
  • Since North Korea has used terror crime as a means of unification under communism against South Korea, South Korea has been much damaged until now. And the occurrence possibility of terror crime by North Korean authority is now higher than any other time. The North Korean terror crimes of Kim Il Sung era had been committed by the dictator's instruction with the object of securing governing fund. However, looking at the terror crimes committed for decades during Kim Jung Il authority, it is revealed that these terror crimes are expressed as a criminal behavior because of the conflict to accomplish the power and economic advantage non powerful groups target. This study focused on the power conflict in various causes of terror crimes by applying George B. Vold(1958)'s theory which explained power conflict between groups became a factor of crime, and found the aspect by ages of terror crime behavior by North Korean authority and responding plan to future North Korean terror crime. North Korean authority high-ranking officials were the Labor Party focusing on Juche Idea for decades in Kim Il Sung time. Afterwards, high-ranking officials were formed focusing on military authorities following Military First Policy at the beginning of Kim Jung Il authority, rapid power change has been done for recent 10 years. To arrange the aspect by times of terror crime following this power change, alienated party executives following the support of positive military first authority by Kim Jung Il after 1995 could not object to forcible terror crime behavior of military authority, and 1st, 2nd Yeongpyeong maritime war which happened this time was propelled by military first authority to show the power of military authority. After 2006, conservative party union enforced censorship and inspection on the trade business and foreign currency-earning of military authority while executing drastic purge. The shooting on Keumkangsan tourists that happened this time was a forcible terror crime by military authority following the pressure of conservative party. After October, 2008, first military reign union executed the launch of Gwanmyungsung No.2 long-range missile, second nuclear test, Daechung marine war, and Cheonanham attacking terror in order to highlight the importance and role of military authority. After September 2010, new reign union went through severe competition between new military authority and new mainstream and new military authority at this time executed highly professionalized terror crime such as cyber/electronic terror unlike past military authority. After July 2012, ICBM test launch, third nuclear test, cyber terror on Cheongwadae homepage of new mainstream association was the intention of Km Jung Eun to display his ability and check and adjust the power of party/military/cabinet/ public security organ, and he can attempt the unexpected terror crime in the future. North Korean terror crime has continued since 1980s when Kim Jung Il's power succession was carried out, and the power aspect by times has rapidly changed since 1994 when Kim Il Sung died and the terror crime became intense following the power combat between high-ranking officials and power conflict for right robbery. Now South Korea should install the specialized department which synthesizes and analyzes the information on North Korean high-ranking officials and reinforce the comprehensive information-collecting system through the protection and management of North Korean defectors and secret agents in order to determine the cause of North Korean terror crime and respond to it. And South Korea should participate positively in the international collaboration related to North Korean terror and make direct efforts to attract the international agreement to build the international cooperation for the response to North Korean terror crime. Also, we should try more to arrange the realistic countermeasure against North Korean cyber/electronic terror which was more diversified with the expertise terror escaping from existing forcible terror through enactment/revision of law related to cyber terror crime, organizing relevant institute and budget, training professional manpower, and technical development.

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