Productivity and Cost of Tree-length Harvesting Using Cable Yarding System in a Larch (Larix leptolepis) Clear-cutting Stand

정응진,조구현,조민재,최병구,차두송 강원대학교 산림과학연구소 2017 Journal of Forest Science Vol.33 No.2

The purpose of this study was to examine productivity and cost of tree-length harvesting using cable yarding system in a larch (Larix leptolepis) clear-cutting stand located in Pyeongchang-gun, Gangwon-do. We used tree-length harvesting method using cable yarding system with a tower yarder HAM300. The productivity was 17.6 m3/hr for felling, 12.4 m3/hr for delimbing, 4.2 m3/hr for yarding, and 8.1 m3/hr for processing. The total cost of the harvesting system was 48,381 won/m3, which was majorly composed of yarding operation cost, at 40,169 won/m3 (79.3%), while felling had the lowest cost at 1,154 won/m3 (4.1%). Major factors affecting felling and processing productivity was tree volume and the number and thickness of branches for delimbing productivity. In addition, we suggest that training and education for machine operators were critical to improve yarding productivity.

군무원 선발제도 개선 방안 연구

정응진 미래군사학회 2022 한국군사학논총 Vol.11 No.2

This study aims to derive the current status and improvement plan of the selection system for military personnel according to the defense reform 2.0, which increases the role of military personnel and expands the quota. The selection of human resources with the importance, expertise, and continuity of the role of military personnel in the defense organization is a decision-making process to select appropriate human resources as a serious task directly related to military combat power. Therefore, it sought to develop a selection system for NCS-based competency-based recruitment, such as job-based competency evaluation and interview evaluation, which are the core of NCS(National Competency Standards)-based competency-based recruitment, and proposed an efficient use of the organization and system. First, it is necessary to improve the selection system centered on job competency required for the position after hiring by switching to the NCS recruitment process rather than the existing career and theoretical evaluation. Second, it is necessary to review as a way to expand professional interviewers and use them professionally in the interview stage. Third, the Ministry of National Defense and the Army, Navy, and Air Force's military personnel selection organizations are integrated under the Ministry of National Defense to be in charge of selection, thereby establishing a professional and efficient work support system. The significance of this study can be used as a document based on legal and institutional improvement in relation to the military personnel selection system, and can be provided as basic data related to the military personnel acquisition policy. 본 연구는 국방개혁 2.0에 따라 군무원의 역할 증대와 정원 확대에 따른 군무원의 선발제도의 현주소와 개선방안을 도출하는 데 있다. 국방조직에서 군무원 역할의 중요성과 전문성 및 연속성을 갖춘 인재 선발은 군 전투력과 직결되는 중대한 과제로서 적합한 인재를 선택하는 의사결정과정이다. 따라서 최근 모든 공공기관에서 시행되고 있는 NCS(국가직무능력표준) 기반 능력 중심 채용의 핵심인 직업기초능력 및 직무수행능력 평가, 면접 평가 등 NCS 기반 능력 중심 채용을 위한 선발제도로 발전시키는 방안을 모색하였고, 또한 조직과 제도를 통합하여 효율적으로 활용하는 방안도 제시하였으며, 연구 결과는 다음과 같다. 첫째, 기존의 경력 및 이론평가 위주의 선발보다는 NCS 채용 절차로 전환하여 채용 후 해당 직위에서 요구되는 직무능력 위주의 선발제도 개선이 필요하다. 둘째 전문면접관을 확대하여 전문적으로 면접단계에서 활용하는 방안으로 검토가 필요하다. 셋째 국방부와 육·해·공군의 군무원 선발조직을 국방부 산하로 통합하여 선발업무를 전담함으로써 전문적이고, 효율적인 업무지원 시스템을 갖추는 것이다. 본 연구는 의의는 군무원 선발제도와 관련하여 법적, 제도적 정비에 근거 문서로 활용이 가능할 것이며, 군무원 획득정책 관련 기초자료로 제공될 수 있을 것이다.

Characteristics of forest road cut slopes affecting the movement of mammals in South Korea

정응진,조민재,조현민,조범준,한상균 한국산림과학회 2021 Forest Science And Technology Vol.17 No.3

Existing forest roads that are the base infrastructure foundation for forest management have been built with a focus on structural stability rather than ecological impact. In recent, however, the concerns on the ecological and environmental impacts on the forest road construction has been increased with the emphasis of sustainable forest management and the improvement of public awareness. Especially, the cut slopes that occurred on the forest road construction are known to affect the movement and habitat of wild animals living in the forest. This study aims to establish environmental and structural standards for the cut slopes by identifying the effect of forest road cut slopes on the movement of wild animals based on a survey of national forest roads in South Korea (30km in total). Seven factors associated with forest road cut slopes, including cut slope length, cut slope gradient, soil type, longitudinal position, crossing position, aspect, and vegetation coverage, as well as wildlife tracks were investigated. As a result of statistical analysis using cross tabulation to determine the correlation of wildlife tracks with each cut slope factor, five factors (soil type, cut slope gradient, cut slope length, vegetation coverage, and crossing position) were significantly identified. Using these five factors, a prediction model to predict whether wildlife move or not on the cut slope was developed, and the discriminant hit ratio was 76.0%. Thus, using such models, there is a need to develop the guidelines of forest road installation considering the wildlife movement and of ecological corridor installation for more eco-friendly forest road construction and design in the future.

반복세탁이 산림작업복 하의의 수축률에 미치는 영향

정응진,박수규,한상균,차두송 한국산림과학회 2019 한국산림과학회지 Vol.108 No.3

본 연구는 체인톱에 의한 산림작업 안전사고 저감을 위하여 산림작업복 하의 4개 품목을 대상으로 작업복 17개부위의 수축률을 측정하였다. 추가적으로 품목 및 반복세탁횟수에 따른 산림작업복의 하의의 적합성을 검토하고 반복세탁을 통한 산림작업복의 사용권장 기간을 제시하였다. 산림작업복 하의 4개 품목의 반복세탁에 따른 수축률 결과, 대부분의품목이 세탁 20회에서 수축률 기준인 6%가 초과되는 부위가 1개소씩 발생하였으며, 가로방향 측정부위가 세로방향 측정부위보다 더 크게 수축되었다. 또한 산림작업복 하의 수축률의 영향을 미치는 인자로는 반복세탁횟수(p<0.05)와 측정부위(p<0.05)로 나타났으며, 측정부위별 수축율에 있어서 총 5개 부위(a, b, g, j, n)가 반복세탁횟수와 유의성이 있는 것으로(p<0.05) 나타났다. 따라서, 산림작업복 하의의 사용 권장기간은 10개월 정도로 판단되며, 추후 반복세탁횟수와 측정부위와의 관계를 상세 분석하여 산림작업복 하의의 내구성에 대해 검토할 예정이다. In order to reduce the safety risk of forestry operations, this research was conducted to examine the suitability of chainsaw protective pants after repeated laundering, testing four different products that are currently used in hand-held chainsaw operations. Laundering was repeated 10, 20, 30, 40, and 50 times. After washing, we measured the shrinkage ratio of 17 measurement positions mostly affecting the safety of forest operations and suggested the expected safety life cycle of chainsaw protective clothes. The results showed that most of the products have only one measurement position where the standard shrinkage ratio (<6%) was exceeded after 20 washings, and that the lateral direction of measurement positions shrank more than the vertical one. The numbers of repeated launderings and measurement positions were found to be significant factors influencing the shrinkage ratio (p<0.05). In the shrinkage rates for 17 measurement positions, there were significant correlations between five of the measurement positions (a, b, g, j, and n) and the number of repeated launderings (p<0.05). Therefore, the results suggest that about 10 months would be suitable for an adequate safety lifetime for chainsaw protective pants. The relationship between the number of repeated launderings and the measurement positions will be further analyzed in detail to examine the durability of chainsaw protective pants.

소나무 임분에서의 트랙터윈치를 이용한 집재작업 생산성 및 비용분석

정응진,조민재,박정묵,조구현,유영민,차두송 한국산림과학회 2019 한국산림과학회지 Vol.108 No.4

The present study analyzed the productivity and cost of winching operations for evaluating the efficiency of a tractor-attached winch in a Pinus densiflora thinning site located in the Yangyang County of Gangwon-do. The mean yarding distance and mean timber volume were 29 m and 0.15 ㎥, respectively. In the 95 cycles of yarding operations, the uphill and downhill yarding operations constituted 51% and 49%, respectively, of the total yarding operations. The productivity of the uphill yarding operation was 2.28 ㎥/h, and the productivity of the downhill yarding operation was 1.89 ㎥/h. The findings of this study revealedthat productivity would increase by 0.5 ㎥/h when the rate of utilization of the machine is increased to 80% by reducing the operational delay time. The cost of the downhill yarding operation was 44,116 KRW/㎥, whereas that of the uphill yarding operation was 53,369 KRW/㎥. The difference in cost resulted from the difference in the number of yarding stems (stems/cycle). Furthermore, the results of the multiple linear regression equation developed for predicting the yarding operation times showed that productivity was significantly affected by working conditions such as yarding distance (m), the number of stems per cycle (stems/cycle), and the terrain slope (%) in the uphill and downhill yarding operations. Further research is required for developing an accurate prediction model equation according to a yarding direction. 본 연구는 임목수확작업에 사용되는 트랙터윈치의 작업효율성을 검토하기 위하여 강원도 양양군지역의 소나무 간벌지를 대상으로 트랙터윈치를 이용한 전목 집재작업에서의 작업생산성 및 작업비용을 분석하였다. 평균집재거리는 29m, 평균 임목재적은 0.15㎥으로 총 95회 집재작업 중 상향집재가 51%, 하향집재가 49%로 작업이 실행되었다. 집재작업 생산성은 하향집재 2.28㎥/hr, 상향집재 1.89㎥/hr으로 운용적 작업지연시간을 최소화하여 기계이용률을 80%로 높일 경우, 약0.5㎥/hr 생산성이 향상될 것으로 판단된다. 집재작업비용은 하향집재 작업비용(44,116원/㎥)이 집재본수(본/cycle)의 차이로 인하여 상향집재작업비용(53,369원/㎥) 보다 낮게 산출되었다. 또한 상·하향 집재작업시간 예측모델식을 개발하여, 민감도 분석을 실시한 결과, 집재거리(m), 집재본수(본/cycle), 집재경사(%) 순으로 집재작업시간에 영향을 미치는 것으로 분석되었다. 향후 집재방향에 따른 정확한 예측모델식을 개발하기 위하여 추가적인 조사가 필요할 것으로 사료된다.

기초자치단체 비상대비조직 개선방안 연구

정응진 (사)위기관리이론과실천 2023 Crisisonomy Vol.19 No.4

In the event of a crisis, an emergency preparedness organization that oversees and coordinates emergency preparedness tasks from basic local governments to the central government plays a very important role. However, related laws and regulations are mainly composed of exhibitions, and emergency preparedness personnel often serve as disaster, safety management, and civil defense, and lack of expertise due to the perception that they are non-preferred positions and frequent job transfers. By expanding the scope of emergency preparedness work in peacetime in preparation for diversifying North Korean threats and national crises and emergencies, the effective operation of emergency preparedness organizations should be guaranteed. The person in charge of emergency preparedness of basic local governments should be reorganized, and professionalism should be improved through regular job training. In addition, it is necessary to ensure conditions for integrated crisis management during wartime and peacetime by revising laws and regulations such as the Emergency Preparedness Resource Management Act and the Integrated Defense Act. 위기상황 시 기초자치단체에서부터 중앙정부까지 비상대비업무를 총괄·조정하는 비상대비조직은 매우중요한 역할을 한다. 하지만 관계 법령은 전시 위주로 구성되어 있고, 재난·안전관리에 무게중심을 두다보니 비상대비인력은 재난·안전관리 및 민방위업무와 겸직을 하는 경우가 많았으며, 비선호 보직이라는 인식과 잦은 보직이동 등으로 전문성이 결여된 부분도 노정되었다. 다양화되는 북한 위협과 국가의위기·비상상황에 대비하여 평시 비상대비업무의 영역을 확장함으로서, 비상대비조직의 효과적인 운영을 보장해야 한다. 기초자치단체의 비상대비업무 담당자를 신편하고, 주기적인 직무교육을 통해 전문성도 제고해야 한다. 또한 비상대비자원관리법과 통합방위법 등 법령을 개정하여 전·평시 통합된 위기관리를 할 수 있는 여건 보장이 필요하다.

병역자원 감소에 따른 육군 초급간부 획득 홍보방안 연구

정응진 ( Jeong¸ Eung Jin ) 미래군사학회 2021 한국군사학논총 Vol.10 No.1

This study is a study on the promotion plan for obtaining beginner officers according to the reduction of military service resources. With two variables, the reduction of military resources and the change in the environment for acquiring defense manpower, analysis of environmental changes for securing excellent manpower for the specialization of beginner officers, which is a key factor, as the key to promoting military structural reform is fostering a technology- intensive elite military. And, accordingly, the promotion plan for customized acquisition of Generation Z was studied. First, from the viewpoint of the environment for acquiring defense personnel, the shortage of military service resources will intensify, and accordingly, the environment for acquiring the army's beginner officers will be worse. Second, from the perspective of changes in new media trends, the justification is raised that public relations by public institutions should also maximize public relations effects by introducing advertising and marketing techniques. Third, from the point of view of the media usage of 'Generation Z', it will be necessary to make full use of promotional strategies such as Audience Targeting, Native Advertising, and Micro-Moments. Fourth, from the perspective of the army manpower acquisition promotion organization and budget, the need to reinforce and integrate the recruitment promotion organization and budget is raised. We believe the PR budget, which is focused on, should be significantly increased.

Harvesting Cost and Productive of Tree-Length Thinning in a Pinus densiflora Stand Using the Tower Yarder (HAM300)

조민재,조구현,정응진,이준,최병구,한상균,차두송 강원대학교 산림과학연구소 2016 Journal of Forest Science Vol.32 No.2

Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was 8.6 m³/hr, followed by delimbing (5.1 m³/hr), yarding (3.5 m³/hr), and processing (8.1 m³/hr). The total cost for the tree-length logging system was 58,446 won/m³, of which the majority was incurred by the yarding cost at 46,217 won/m³ (79.3%), whereas the lowest cost was for felling at 2,359 won/m³ (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

벌도 및 가지제거작업에서 세 가지 인간공학적 위험 평가기법의 비교분석

조민재 ( Min-jae Cho ),정응진 ( Eung-jin Jeong ),오재헌 ( Jae-heun Oh ),한상균 ( Sang-kyun Han ) 한국산림과학회(구 한국임학회) 2021 한국산림과학회지 Vol.110 No.2

우리나라 모든 산업에서 근골격계질환은 작업자들의 안전에 큰 영향을 미치고 있으며, 산림작업은 산업안전보건법에 따라 근골격계 부담작업으로 분류된다. 특히 벌도 및 가지제거작업은 주로 인력작업으로 실시되고 있으며, 작업원의 안정성 확보를 위해 작업자세에 대한 평가가 필요하다. 따라서 본 연구는 체인톱을 이용한 벌도 및 가지제거작업의 작업자를 대상으로 세가지 인간공학적 분석 도구(OWAS, RULA, REBA)를 이용하여 위험도를 평가하고, 평가기법별 작업자세에 대한 영향인자를 분석하였다. 벌도와 가지제거작업자세의 위험도는 RULA, OWAS, REBA 순으로 높게 평가되었으며, 대부분 2∼3단계로 작업자세의 즉각 변경조치는 요구되지 않았다. 하지만 벌도작업에서 허리와 다리를 굽힌자세와 가지제거작업에서 벌도목 위에서 작업하는 자세는 위험도가 매우 높게 분석되었다. 또한 벌도작업의 경우 산지경사, 가지제거작업의 경우는 지상에서부터 벌도목 높이가 작업위험도 평가에 영향이 높은 것으로 분석되었다. 따라서 산림작업에 있어서 작업자의 안전성을 확보하기 위해 작업부하가 낮은 자세(벌도작업: 쪼그리는 자세, 가지제거작업: 허리와 다리가 곧은 자세)로 작업하는 것이 바람직한 것으로 사료된다. Musculoskeletal disorders affect workers' safety in most industries, and forest operations are classified as a musculoskeletal burden according to the Occupational Safety and Health Act in South Korea. In particular, felling and delimbing operations are mainly conducted by manpower, and then, it is necessary to evaluate ergonomic risk assessment for safety of felling and delimbing workers. Three ergonomic risk assessment methods, such as Ovako Working posture Analysis System (OWAS), Rapid Upper Limb Assessment (RULA), and Rapid Entire Body Assessment (REBA), are available for assessing exposure to risk factors associated with timber harvesting operations. Here, three ergonomic risk assessment methods were applied to examine ergonomic risk assessments in chainsaw felling and delimbing operations. Additionally, exposure to risk factors in each method was analyzed to propose an optimal working posture in felling and delimbing operations. The risk levels of these operations were evaluated to be highest in the RULA method, followed by the OWAS and REBA methods, and most of the exposed working postures were examined with a low-risk level of two and three without requiring any immediate working posture changes. However, two significant working postures, including the bending posture of the waist and leg in felling operation and standing posture on the fallen trees in delimbing operation, were assessed as the high-risk level and needed immediate working posture changes. Low-risk work levels were examined in the squatting posture for felling operation and the straightened posture of the waist and leg for delimbing operation. Moreover, the slope in felling operation and the tree height in delimbing operation significantly affected risk level assessment of working posture. Therefore, our study supports that felling and delimbing workers must operate with low-risk working postures for safety.

임목수확방법별 벌도작업 생산성 및 비용 분석

조민재 ( Min-jae Cho ),최윤성 ( Yun-sung Choi ),문호성 ( Ho-seoung Mun ),이충건 ( Chung-geon Lee ),이은재 ( Eun-jai Lee ),정응진 ( Eung-jin Jung ),오재헌 ( Jae-heun Oh ),한상균 ( Sang-kyun Han ),김대현 ( Dae-hyun Kim ),차두송 ( Du 한국임학회 2016 한국산림과학회지 Vol.105 No.4

본 연구는 동일한 임분조건에서 작업자 2명(A: 작업경력 5년 이하, B: 작업경력 15년 이상)을 대상으로 임목수확방법별(전목수확·전간수확·단목수확)에 따른 벌도작업의 작업생산성과 비용을 분석하였다. 전목작업에서 작업자A의 생산성은 10.3 m³/SMH, 작업비용은 2,066원/m³이며, 작업자 B는 생산성 12.7 m³/SMH, 작업비용 2,201원/m3으로 산출되었으며, 시간당 생산성은 작업자 B가 다소 높았지만, 작업비용은 작업자 B의 높은 임금으로 작업자 A가 약간 낮게 나타났다(p>0.05). 전간작업의 경우 작업자 A와 B의 생산성은 각각 2.2 m³/SMH과 3.3 m3/SMH이며, 작업비용은 각각 9,890원/m³과 8,459원/m³으로, 작업자 B가 A보다 생산성은 높게, 작업비용은 낮게 산출되어 작업의 숙련도에 따라 큰 차이를 보이고 있었다(p< 0.05). 단목작업에서 작업자 A와 B의 생산성은 2.3 m³/SMH과 3.0 m³/SMH, 작업비용은 9,584원/m3, 9,395원/m³으로, 작업자 B의 생산성이 높고, 작업비용은 낮게 산출되었다(p >0.05). 이와 같이 벌도작업 중에서도 임목의 절단작업과 같이 높은 숙련도를 요구하지 않는 단순작업에서는 오히려 작업자의 임금이 생산비용에 크게 영향을 미치는 것으로 나타났다. 또한 가지정리와 같이 임지 내 벌도목 사이를 이동하며, 작업하는 것은 작업자의 높은 숙련도가 작업경비의 저감에 영향을 미치는 것으로 판단된다. The purpose of this study was to broaden our knowledge on the productivity and costs of felling operation in three different harvesting methods(whole tree, tree-length and cut-to-length). Felling was conducted in three different harvesting methods with two workers who have different work experiences. Worker A and B have had felling experiences for about 5 years and 15 years, respectively. Felling productivity in whole tree method was 10.3 m³/SMH for worker A and 12.7 m³/SMH for worker B. Felling costs for worker A and B were 2,066 won/m3 and 2,201won/m³, respectively. Although felling productivity of worker B in whole tree method was higher than worker A, felling costs of worker A were similar to worker B because the wage of worker B was more expensive than the wage of worker A (p>0.05). In tree-length method, felling cost of worker B were cheaper than that of worker A. Felling productivity and cost in tree-length method were 2.2 m³/SMH and 9,890 won/m3 for worker A and 3.3 m³/SMH and 8,459 won/m³ for worker B, respectively (p< 0.05). In cut-to-length method, felling productivity and cost were 2.3 m³/SMH and 9,584 won/m³ for worker A and 3.0 m³/SMH and 9,395 won/m³ for worker B, respectively. Felling productivity of worker B was higher than that of worker A (p >0.05). Our preliminary results found that harvesting methods and worker`s experiences highly affect on the productivity and costs of felling operations. These results should be useful for forest managers when planning cost-effective harvesting operations.