화이트 오크 심재의 온도단계 열판건조에 관한 연구

정희석,찰리코즈리크 한국목재공학회 1983 목재공학 Vol.11 No.5

Press-drying was used an 0.25 inch-and 0.50 inch-thick flatsawn board of Oregon white oak heartwood at platen temperature of constant boiling point (212 F), constant lower plateau temperature (244 F) and combination of boiling point for 40 minutes and lower plateau temperature later by using platen pressure of 35 pounds per square inch to explore the effect of temperature step-press drying on drying rate and honeycombing. The results of study were same as follows. 1. Press-drying of constant boiling point increased drying times and decreased honeycombing considerably for boards of bath thicknesses. 2. Press-drying of constant plateau temperature reduced drying times but showed severe honeycombing for boards of both thicknesses. 3. Press-drying of temperature step-press drying decreased drying times and honeycombing far 0.25 inch thick boards the same as press-drying of constant lower plateau temperature, but not decreased drying times and honey-combing for 0.50 inch-thick boards.

참오동나무재의 음향성, 목재의 계절별 천연건조 속도, 열기건조, 고온건조, 진공건조 특성 및 목재와 목질

정희석 서울대학교 농업생명과학대학 농업개발연구소 1997 농업생명과학연구 Vol.1 No.-

板材와 單板의 熱板乾燥에 關한 硏究

鄭希錫 서울大學校 農科大學 1979 서울대농학연구지 Vol.4 No.1

Current rapid increase in the wood demand promotes utilization of fast-growing species and small diameter log as timber resources. These woods have a greater proportion of juvenile wood in their volume, and are unstable in dimension due to anisotropy in shrinkage than mature wood. It is understood that severe drying defects could occur with conventional drying. The present studies aimed to elucidate characteristics on drying such as the core temperature, current moisture content, moisture gradient, drying rate, drying time, dimensional change and drying defect of board, and drying rate of veneer for an efficient utilization of timber resources. Species selected for the study were poplar(P. euramericana G.) as a fast-growing species and oak(Q. acutissima C.) as refractory wood. The condition of press-drying adopted was that of platen temperature of 175℃ and pressure of 2.46 kilogram per square centimeter with board thickness of 7, 15 and 24 milimeters. For veneer experiment, the conditions adopted were of temperature of 110℃, 120℃ and 130℃ and pressure of 2.46 kilogram per square centimeter, and veneer thickness of 0.6, 1.2 and 1.8 milimeters. The results of the study are summarized as follows. 1. The core temperature of board thicker than 15 milimeters was divided into three stages of drying : the period of initial heating, the period of the stable core temperature and the period of the slowly rising core temperature. On the other hand, the board with 7 milimeters thick did not show the period of the stable core temperature. 2. The plateau temperature of thicker board was lower and kept longer than that of thinner board. For the board with same thickness, the plateau temperature for end-grained board was lower and kept longer than the temperature for flat-grained board. 3. The average moisture content of thicker board was lower than that of thinner board when the core temperature was reached at 150℃. For the board with same thickness and the same core temperature of 130℃, the average moisture content of end-grained board was lower than that of flat-grained board. 4. The variation of the moisture content in relation to the drying time showed a curvilinear, and that of thinner board changed much faster than that of thicker board. For the board with same thickness the drying rate of end-grained board was greater than that of flat-grained board. 5. The moisture gradient in board was great at the beginning stage of drying, but decreased as the drying was progressed. 6. The drying rate of flat-grained boards showed a positive correlation with the initial moisture content, platen temperature and the pressure applied, but a negative correlation with the board thickness and drying time. 7. The drying time of flat-grained boards showed a positive correlation with the board thickness and initial moisture content, but a negative correlation with platen temperature, pressure and final moisture content. 8. The drying rates of poplar flat-grained boards treating with cold water, hot water and steam were greater than that of controlled(untreated) specimen. 9. The thickness shrinkage of boards for press-drying increased as the drying was progressed. The thickness shrinkage of edge-grained boards was greater than that of flat-grain, and its shrinkage of end-grain was the least. The width of edge-and flat-grained boards expanded as the drying was progressed, but in contrast the end-grained board shrank. 10. The thickness shrinkage of edge-and flat-grained boards increased with pressure applied. The thickness recovery of edge-grained board in relation to pressure variation showed significant difference, but that of flat-grain showed no significant difference. 11. Except for board with high moisture content and drying condition of higher platen temperature and higher pressure, poplar flat-grained boards dried without a serious drying defect such as surface check, honeycomb and collapse. The end-grained board was also showed no significant drying defects. 12. Drying defects of sapwood board was milder than that of heartwood. Drying defects of oak heartwood with steaming treatment reduced the amount of drying defects as compared to those with cold water and hot water treatments. 13. The drying rate of veneer was decreased as drying was progressed. The tinner veneer thickness and higher platen temperature, the greater the drying rate was.

동북아 다자안보협력과 러시아

정희석 경북대학교 평화문제연구소 2005 평화연구 Vol.30 No.-

소나무와 리기다소나무 평소각재(平小角材)의 고온건조

정희석,박문재 한국목재공학회 1987 목재공학 Vol.15 No.2

Korean red pine (Pinus densiflora S. et Z.) and pitch pine (Pinus rigida Mill) 5×10㎝ dimension lumber were dried in a kiln providing a cross-circulation velocity of 5 m/sec at dry-and wet-bulb temperatures of 116 and 71℃, followed by 3 hours at 91 and 85℃. Compared to dimension lumber dried at temperatures not in excess of 80℃, drying times and drying defects of the high-temperature dried lumber were as follows. 1. To dry to 10 percent moisture content, the high-temperature schedule of Korean red pine and pitch pine lumber took less than one seventh the time required by the conventional kiln drying schedule. 2. High-temperature drying rate and conventional drying rate to 10 percent moisture content of Korea red pine lumber were 2.75 and 0.35%/hr, and those of pitch pine lumber were 3.38 and 0.46%/hr, respectively. 3. Compared to lumber of both species on conventional schedule, moisture gradient of high-temperature lumber was greater. 4. Compared to lumb on conventional schedule, maximum surface checking of high-temperature lumber of both species was severer, and maximum end cheking of high-temperature lumber of both species was similar to that of lumber on conventional schedule. 5. Compared to lumber on conventional schedule, Korean red pine lumber dried at high-temperature showed more hoeycombing, but pitch pine lumber dried at high-temperature showed significantly sligher honeycombing. 6. Compared to lumber on conventinal schedule, the high-temperature lumber showd less warping in lumber of both species. 7. Collapse and casehardening of Korean red pine and pitch pine lumber on both scheules were slight.

韓國産 伊太利포푸라材의 木纖維의 變異

鄭希錫 서울대학교 1975 서울대학교 論文集 Vol.25 No.-

This study was carried out to investigate on the variation of the fiber dimension of Italian poplar hybrid (P. euramericana I-476). Three nine­years old Italian poplar hybrid was sampled from a plantation at Ansug Kun, Kyunggido and fell in May. Every annual ring was prepared for specimens from pith to bark by the heights from the bases. Fiber length and width measured are given in table 1 and 2. From the result of these investigation, several conclusion can be drawn. 1. Fiber length increase from the pith to outer wood. This is valid for all heights. Fiber length is seen to increase rapidly with increasing height from the base. 2. Variation in fiber length at the height position in the stem position increase slightly from the base to 3.2 meter position, and then decrease toward the top of stem. 3. In general, there is a small increase in fiber width from pith to outer wood of the stem, but no pattern with height is evident. 4. Fiber lengths by the height positions range 0.658 to 1.207 millimeter and average fiber length is 0.953 millimeter. Fiber width by the height positions range 19.7 to 28.3 micron and average fiber width is 24.4 micron.

탈냉전 시대 유엔의 강제적 인권레짐의 형성배경과 실태

정희석,김도균 慶北大學敎 社會科學大學 2005 社會科學 Vol.17 No.-

본 논문에서는 잭 도넬리의 인권레짐 분석을 기초로 탈냉전 시대 유엔의 강제적 인권레짐의 형성배경과 실태에 대해 연구하였다. 잭 도넬리는 『국제인권 : 레짐분석』이라는 논문에서 국제인권레짐을 선언적 레짐, 장려적 레짐, 실행적 레짐, 그리고 강제적 레짐으로 분류하여 서술하고 있다. 그러나 그는 유엔에 의한 강제적인 인권레짐의 형성은 불가능한 것으로 보고 있으며 강제적 인권레짐이 형성되기 위해 「국제적인 의사결정」과 「국제적인 감시체제」가 형성되어야함을 설명하고 있다. 이러한 분석의 기준에 덧붙여 본 논문에서는 「국가주권에 대한 제한」 및 「국제법의 주체로 인식된 개인」을 강제적 인권레짐이 형성될 수 있는 기준으로 설정하고 그 시대적인 요인을 네 가지로 분석했다. 첫째, 구 소련과 구 동구권 공산국가들, 그리고 제 3세계 국가들의 민주화의 실패로 야기된 대규모 인권침해사태, 둘째, 세계화의 확대에 따른 정치적, 경제적, 사회적 측면에서의 인권침해 현상, 셋째, 저강도 분쟁으로 불리는 새로운 국제분쟁의 유형과 국내분쟁의 급증으로 인한 집단학살이나 대규모 살육과 같은 인권침해사태의 증가, 마지막으로, 인간안보를 중심으로 새롭게 대두된 신안보개념의 등장 등이 유엔에 의한 강제적 인권레짐의 가능성을 담보해낼 시대적인 요인이라고 보았다. 이러한 현실적인 유엔의 강제적 인권레짐 실태로는 심각한 인권침해를 저지르는 국가에 대한 유엔안보리의 인도주의적인 군사적 · 경제적 제재조치, 인도주의적인 관점에서 탈냉전 시대 변화해 가는 유엔의 평화유지활동, 전 세계적인 감시체제를 가동하면서 유엔의 인권정책을 통합한 유엔 인권고등판문관 활동, 그리고 심각한 인권침해를 저지른 각 국의 개인범죄자들을 처벌할 수 있는 국제형사재판소 활동 등을 들 수 있다. The purpose of this study is to analyze on the background and the realities of the United Nations' enforcement regime for human rights in post-cold war era. In 1986, Jack Donnelly presented the most prominent paper in the international human rights field called "International Human Right : A Regime Analysis." In the paper, he regarded international human rights activities as human rights regime and arranged the international human rights regime into four categories, declaratory regime, promotional regime, implementation regime, and enforcement regime. There are two major problems in his international human rights regime analysis. First of all, he insists that enforcement regime would be hard to be realized in the international society because of nation states sovereignty. Secondly. he ignores the important role of human rights Non-Government Organizations at the level of international politics. Because of the date of his thesis, he couldn't focus on human rights regime in the post-cold war era. This thesis gives the major reasons for the United Nations' enforcement regime for human rights. Why is United Nations' enforcement regime for human rights necessary in the world? First, the side-effect of democratization is more serious human rights violations in former Soviet Union and the Third World. Second, globalization has had a negative effect on human rights on the political, economic, and social level. Third, low-intensity conflict throughout the world has caused more death and injury than it did during the cold war and civil was has also broken out more frequently than interstate conflict since cold war. This means the United Nations peace-keeping operations have suddenly had to increase due to the increase of low-intensity conflict or civil war. Finally, a new security concept has replaced the traditional security concept. It mainly focuses on human security including social, economic, environmental security. This thesis mainly presents four major categories of the United Nations' human rights enforcement regime. These are the United Nations Security Council, the United Nations Peace-keeping Operations, the United Nations High Commissioner for Human Rights, and the United Nations International Criminal Courts.

소나무ㆍ잣나무 구조용 제재의 가열판 압체식 진공건조 기술개발

정희석 서울대학교 농업생명과학대학 농업개발연구소 1998 농업생명과학연구 Vol.2 No.-

In this investigation for the drying characteristics of red pine and white pine, drying rate was very fast. Internal temperature was reached at set point in three hours, and whole wood temperature were nearly same in the last stage of drying. It presents low drying defects and low electrical energy consumption. It showed much potentials for thick lumber over 10cm to dry.

동해 표층 해류와 해표면 수온의 연간 변동성과 계절 변동성

정희석,최병주,이상호,변도성 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5

가열판 압체식 진공건조의 침엽수 제재두께와 건조시간계수의 관계

정희석 서울대학교 농업개발연구소 2000 농업생명과학연구 Vol.4 No.-

Red pine, white pine, larch and western hemlock lumber were vacuum-press dried under three drying schedules to investigate current moisture contents(MC), drying rates and drying time factors related to five lumber thicknesses. Current MC could be estimated by drying factors such as lumber thickness, initial MC and drying time. Average drying rate from 30% to 15% MC was the highest for western hemlock below fiber saturation point, red pine, white pine and larch in the order of their magnitude. Drying rate curvilinearly decreased as lumber thickness increased. Drying time factor curvilinearly increased as lumber thickness increased.